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Bulman A, D'Cunha NM, Marx W, Turner M, McKune A, Naumovski N. The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis. Sleep Med Rev 2025; 81:102076. [PMID: 40056718 DOI: 10.1016/j.smrv.2025.102076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 12/16/2024] [Accepted: 02/18/2025] [Indexed: 03/10/2025]
Abstract
This systematic review ansd meta-analysis aimed to evaluate the effects of L-theanine, a non-proteinogenic amino acid found in tea, on sleep outcomes. Literature searches were conducted in five electronic databases (APA PsycINFO, CINAHL, Medline, Scopus, Web of Science), and one register (Cochrane Central Register of Controlled Trials) from inception until September 2024. Randomised controlled trials investigating the effects of L-theanine supplementation on sleep quality in humans of all ages and health status were included. Nineteen articles (N = 897 participants) were selected and 18 included in the meta-analysis. L-theanine was shown to significantly improve subjective sleep onset latency (SMD = 0.15, 95 % CI [0.01, 0.29], p = 0.04; n = 10 studies), subjective daytime dysfunction (SMD = 0.33, 95 % CI [0.16, 0.49], p < 0.001; n = 9 studies), and overall subjective sleep quality score (SMD = 0.43, 95 % CI [0.04, 0.83], p = 0.03; n = 12 studies). The findings indicate the potential use of L-theanine in the management of sleep disturbances; however, the lack of studies on "pure" L-theanine warrants further investigation. Future studies are needed to determine the adequate dose and duration of L-theanine supplementation for improving and maintaining sleep quality in healthy and clinical populations.
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Affiliation(s)
- Amanda Bulman
- Faculty of Health, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; Functional Foods and Nutrition Research (FFNR) Laboratory, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; University of Canberra Research Institute of Sport and Exercise (UCRISE), University of Canberra, Canberra, ACT, 2617, Australia
| | - Nathan M D'Cunha
- Faculty of Health, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; Functional Foods and Nutrition Research (FFNR) Laboratory, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; Centre for Ageing Research and Translation, University of Canberra, Canberra, ACT, 2617, Australia
| | - Wolfgang Marx
- Food & Mood Centre, IMPACT-The Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Deakin University, Barwon Health, Geelong, VIC, 3220, Australia
| | - Murray Turner
- Faculty of Health, University of Canberra, Bruce, Canberra, ACT, 2617, Australia
| | - Andrew McKune
- Faculty of Health, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; Functional Foods and Nutrition Research (FFNR) Laboratory, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; University of Canberra Research Institute of Sport and Exercise (UCRISE), University of Canberra, Canberra, ACT, 2617, Australia; Discipline of Biokinetics, Exercise and Leisure Sciences, School of Health Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa
| | - Nenad Naumovski
- Faculty of Health, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; Functional Foods and Nutrition Research (FFNR) Laboratory, University of Canberra, Bruce, Canberra, ACT, 2617, Australia; University of Canberra Research Institute of Sport and Exercise (UCRISE), University of Canberra, Canberra, ACT, 2617, Australia; Discipline of Nutrition-Dietetics, Harokopio University, Athens, 17671, Greece.
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Kim D, Kim S, Choi G, Lee G, Song J, Oh YT, Youn JH, Cho S. The polyphenol/caffeine ratio determines the arousal-inducing properties of the green tea ethanol extract. Food Funct 2025; 16:3694-3706. [PMID: 40245063 DOI: 10.1039/d5fo00661a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2025]
Abstract
Green tea (Camellia sinensis L.), one of the most popular beverages worldwide, contains caffeine, a natural stimulant. However, some green tea extracts have been known to possess both hypnotic and arousal effects. This study aimed to identify the components influencing these dual effects using a green tea ethanol extract (GE). Response surface methodology revealed that only some extraction conditions significantly induced arousal effects in ICR mice during the pentobarbital-induced sleep test. Among these, extraction with 95% ethanol for 195 minutes achieved the maximum arousal effect, corresponding to a caffeine content of 58.9 mg g-1, comparable to the effects observed with the reference, 25 mg kg-1 of caffeine. In addition, administration of this GE sample significantly increased wakefulness for 3 hours following treatment in C57BL/6N mice, as confirmed through sleep architecture analysis. A correlation analysis of the total phenolic content (TPC) to caffeine ratio in GE found that the intensity of the arousal-inducing effects varied with TPC (R2 = 0.9428). It was also confirmed that the ratio of EGCG to caffeine, major components of GE, was more closely associated with sleep duration (R2 = 0.9034). L-Theanine, known for its sleep-promoting effects, did not independently affect the arousal effects of GE. However, when combined with EGCG, their total content showed a slightly stronger correlation with sleep duration in relation to the caffeine ratio, compared with that of EGCG/caffeine ratio (R2 = 0.9464). Therefore, the balance between TPC and caffeine appears to modulate the stimulant properties of GE, highlighting its potential as both a stimulant and a mild hypnotic agent. Collectively, these findings provide insights into optimizing GE for tailored functional foods based on its polyphenol/caffeine ratio.
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Affiliation(s)
- Duhyeon Kim
- Department of Food Science and Technology/Institute of Food Science, Pukyong National University, Busan 48513, Republic of Korea.
| | - Seonghui Kim
- Department of Food Science and Technology/Institute of Food Science, Pukyong National University, Busan 48513, Republic of Korea.
| | - Gibeom Choi
- Department of Food Science and Technology/Institute of Food Science, Pukyong National University, Busan 48513, Republic of Korea.
| | - Gahyeon Lee
- Department of Food Science and Technology/Institute of Food Science, Pukyong National University, Busan 48513, Republic of Korea.
| | - Junho Song
- Life Science Research Institute, NOVAREX Co., Ltd, 80, Osongsaengmyeong 14 ro, Heungdeok-gu, Cheongju-si 28220, Republic of Korea.
| | - Young Taek Oh
- Department of Physiology and Neuroscience, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA.
| | - Jang H Youn
- Department of Physiology and Neuroscience, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA.
| | - Suengmok Cho
- Department of Food Science and Technology/Institute of Food Science, Pukyong National University, Busan 48513, Republic of Korea.
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Payne ER, Aceves-Martins M, Dubost J, Greyling A, de Roos B. Effects of Tea (Camellia sinensis) or its Bioactive Compounds l-Theanine or l-Theanine plus Caffeine on Cognition, Sleep, and Mood in Healthy Participants: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutr Rev 2025:nuaf054. [PMID: 40314930 DOI: 10.1093/nutrit/nuaf054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2025] Open
Abstract
CONTEXT The bioactive compounds found in tea from Camellia sinensis, namely theanine, caffeine, and polyphenols, can potentially improve short-term and long-term health outcomes. OBJECTIVE The aim of this study was to assess the effects of tea, theanine alone, or theanine plus caffeine on cognition, mood, and sleep outcomes, using data from randomized controlled trials (RCTs) in healthy participants. DATA SOURCES The Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Embase, and Ovid Medline were searched up to and including August 2023. DATA EXTRACTION Data relevant to the participants, interventions, comparisons, outcomes (ie, cognition, mood, and sleep), and study design were extracted. DATA ANALYSIS Fifty RCTs were included in the review, of which 15 were eligible for at least 1 meta-analysis, most commonly performed by use of standardized mean differences (SMD), in random effects models. After intake of theanine plus caffeine, and of placebo, small-to-moderate differences were found between these interventions in the first hour (h1) and second hour (h2), that favoured theanine plus caffeine, with regard to cognition and mood outcomes such as choice reaction time (h1: SMD, -0.48; 95% CI, -1.01, 0.05), digit vigilance task accuracy (h2: SMD, 0.20; 95% CI, 0.02, 0.38), attention switching task accuracy (h2: SMD, 0.33; 95% CI, 0.13, 0.54), and overall mood (h2: SMD, 0.26; 95% CI,-0.10, 0.63). There was a small-to-moderate difference between the effects of theanine and placebo that favored theanine on choice reaction time (h1: SMD, -0.35; 95% CI,-0.61, -0.10). The CIs frequently highlighted the uncertainty surrounding the direction and magnitude of these differences. CONCLUSIONS This meta-analysis provides evidence that theanine plus caffeine, and theanine alone, could be beneficial for cognitive and mood outcomes. More research using tea beverages or tea-equivalent bioactive doses and research in free-living participants is needed. PROSPERO REGISTRATION NO CRD42022351601.
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Affiliation(s)
- Edward R Payne
- The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
| | | | - Joy Dubost
- Lipton Teas and Infusions Research and Innovation, Amsterdam Science Park, Amsterdam, The Netherlands
| | - Arno Greyling
- Unilever Foods Innovation Centre, Wageningen, The Netherlands
| | - Baukje de Roos
- The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
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Wu Q, Wan X, Wang D, Ma M, Hu X, Chen X, Ding X, Zhang C. L-Theanine attenuates oxidative damage induced by heat stress through the PI3K/AKT/Nrf2 signaling pathway in skeletal muscle cells. Poult Sci 2025; 104:105140. [PMID: 40203618 PMCID: PMC12005892 DOI: 10.1016/j.psj.2025.105140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2025] [Revised: 03/26/2025] [Accepted: 04/03/2025] [Indexed: 04/11/2025] Open
Abstract
The rising prevalence of heat stress (HS), because of global warming, presents a considerable challenge to both human and animal health and welfare. L-Theanine (LTA), a naturally occurring amino acid, may enhance poultry muscle yield and quality, suggesting its potential application in alleviating the negative impacts of HS. However, the molecular mechanisms through which LTA exerts its beneficial effects remain to be fully understood. This study explored the protective effects of LTA on cultured broiler skeletal muscle cells under oxidative stress induced by HS, focusing on the molecular mechanisms involved. Our findings indicate that treatment with LTA significantly improved cell survival, bolstered the activity of antioxidant enzymes, decreased reactive oxygen species (ROS) contents and diminished malondialdehyde (MDA) levels in HS-treated cultured cells. Furthermore, LTA enhanced the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways in HS-treated cultured cells, facilitating mitochondrial biogenesis and reducing cell apoptosis. The protective effects of LTA in HS-treated cultured cells were significantly reduced by the PI3K inhibitor LY294002 or the Nrf2 inhibitor ML385. In conclusion, our study showed that LTA protects cultured skeletal muscle cells from HS-induced oxidative damage by modulating the PI3K/AKT/Nrf2 signaling pathway, positioning LTA as a promising natural antioxidant for poultry feed additives aimed at improving muscle health.
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Affiliation(s)
- Qiong Wu
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Dongxu Wang
- School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China
| | - Mingqi Ma
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China
| | - Xinru Hu
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China
| | - Xingyong Chen
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China
| | - Xiaoling Ding
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China
| | - Cheng Zhang
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China.
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Abdul-Wahab HY, Salah R, Abdulbaqi HR. Salivary levels of catalase, total antioxidant capacity and interleukin-1β and oral health-related quality of life after matcha and green tea consumption for patients with gingivitis: A randomized clinical trial. Int J Dent Hyg 2025; 23:114-123. [PMID: 38764154 DOI: 10.1111/idh.12820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 04/16/2024] [Accepted: 05/04/2024] [Indexed: 05/21/2024]
Abstract
OBJECTIVES To evaluate the changes in salivary levels of catalase (CAT), total antioxidant capacity (TAC) and IL-1β (primary outcomes) as well as gingival health and oral health-related quality of life (OHRQOL) 1 month after the consumption of matcha and green tea in adult patients with gingivitis. METHODS This study was a parallel randomized clinical trial. Forty gingivitis adult patients were randomly assigned to drink either matcha or green tea cup twice daily for a duration of 1 month. They were asked to keep their habitual oral hygiene measures. Plaque index (PI) and bleeding on probing (BOP) were recorded. In addition, saliva was collected at baseline and 1 month after tea consumption. Salivary levels of CAT, TAC and IL-1β were determined by ELISA. Each participant was asked to fill OHIP-14 questionnaire before and after tea consumption. RESULTS Following tea intake, 40.6% of the study sample had healthy gingiva. Both groups similarly showed reductions in PI (0.32 ± 0.11-0.22 ± 0.08) and BOP (0.24 ± 0.08-0.13 ± 0.07) scores after tea consumption. There was a significant difference between mean TAC before and after matcha tea consumption only. Non-significant reductions in salivary levels of CAT and IL-1β were detected after tea consumption. OHRQOL of participants was improved after tea, both types, consumption. CONCLUSION Despite study limitations, daily consumption of matcha and green tea might be beneficial as they potentially enhance OHRQOL of individuals with gingivitis and reduce the extent of gingivitis despite non-significant changes in salivary antioxidants and IL-1β levels.
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Affiliation(s)
| | - Rasha Salah
- Department of Periodontics, College of Dentistry University of Baghdad, Baghdad, Iraq
| | - Hayder Raad Abdulbaqi
- Department of Periodontics, College of Dentistry University of Baghdad, Baghdad, Iraq
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Huang Z, Jing H, Pan Y, Cai H, Zhang W, Zhu J, Zhang N, Wu D, Xu W, Qiu H, Bao H, Li G, Ning J, Xian B, Gao S. L-Theanine Extends the Lifespan of Caenorhabditis elegans by Reducing the End Products of Advanced Glycosylation. Foods 2025; 14:221. [PMID: 39856887 PMCID: PMC11764849 DOI: 10.3390/foods14020221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2024] [Revised: 01/09/2025] [Accepted: 01/10/2025] [Indexed: 01/27/2025] Open
Abstract
L-theanine, a non-protein amino acid naturally occurring in tea leaves, is recognized for its antioxidant, anti-inflammatory, and neuroprotective properties. Despite its known benefits, the mechanisms by which L-theanine influences lifespan extension remain poorly understood. This study investigated the effects of L-theanine on the lifespan of Caenorhabditis elegans and explored the underlying mechanisms. Our findings indicate that L-theanine significantly diminishes the accumulation of advanced glycation end products (AGEs), which are biomarkers closely linked to aging and age-related diseases. Through an AGE-level analysis, we observed that L-theanine, when administered during early adulthood, notably extended the lifespan of Caenorhabditis elegans under both normal and high-glucose-induced stress conditions. L-theanine enhanced the lifespan under typical conditions and provided protective effects against high-glucose-induced stress. A further analysis demonstrated that L-theanine extends the lifespan of Caenorhabditis elegans by modulating the DAF-2/DAF-16 insulin-like signaling pathway and reducing the accumulation of advanced glycation end products (AGEs). In summary, this study identified L-theanine as a potential anti-aging intervention that extends the lifespan by reducing AGE accumulation and regulating insulin-like signaling pathways. These findings provide new insights for developing anti-aging strategies and lay the groundwork for further research on the potential benefits of L-theanine in mammals. Future studies could explore the molecular mechanisms, test L-theanine in mammalian models, and assess the long-term side effects.
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Affiliation(s)
- Zhihang Huang
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China; (Z.H.); (H.J.); (W.Z.); (N.Z.); (G.L.); (J.N.)
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Haiming Jing
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China; (Z.H.); (H.J.); (W.Z.); (N.Z.); (G.L.); (J.N.)
| | - Yan Pan
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Hongxia Cai
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Wenjing Zhang
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China; (Z.H.); (H.J.); (W.Z.); (N.Z.); (G.L.); (J.N.)
| | - Jingyuan Zhu
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Nan Zhang
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China; (Z.H.); (H.J.); (W.Z.); (N.Z.); (G.L.); (J.N.)
| | - Dan Wu
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Wentao Xu
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Hexiang Qiu
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Huihui Bao
- NHC Key Laboratory of Food Safety Risk Assessment, Chinese Academy of Medical Science Research Unit, China National Center for Food Safety Risk Assessment, Beijing 100022, China;
| | - Guojun Li
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China; (Z.H.); (H.J.); (W.Z.); (N.Z.); (G.L.); (J.N.)
- School of Public Health, Capital Medical University, Beijing 100069, China
| | - Junyu Ning
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China; (Z.H.); (H.J.); (W.Z.); (N.Z.); (G.L.); (J.N.)
| | - Bo Xian
- Laboratory of Aging Research, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610056, China; (Y.P.); (H.C.); (J.Z.); (D.W.); (W.X.); (H.Q.)
| | - Shan Gao
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China; (Z.H.); (H.J.); (W.Z.); (N.Z.); (G.L.); (J.N.)
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Deshpande SS, Kurdi M, Baiju A, Athira AS, Sarasamma AG, Gangadharan AK. Comparison of the effects of two amino acids, Gamma-aminobutyric acid (GABA) and L-theanine, on sedation, anxiety, and cognition in preoperative surgical patients - A randomized controlled study. J Anaesthesiol Clin Pharmacol 2025; 41:112-118. [PMID: 40026748 PMCID: PMC11867345 DOI: 10.4103/joacp.joacp_417_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 09/22/2023] [Accepted: 11/12/2023] [Indexed: 03/05/2025] Open
Abstract
Background and Aims Preoperational anxiety affects the outcome of anesthesia and surgery. Benzodiazepines impair psychomotor performance and cause excessive sedation. L-theanine is a unique amino acid found in green tea. It prevents stress, produces anxiolysis, modulates alpha activity, and provides beneficial effects on mental state, including sleep quality. Gamma-aminobutyric acid (GABA) is a non-proteinogenic amino acid and a phytochemical that is the main inhibitory neurotransmitter in the mammalian brain. It is beneficial in anxiety and stress regulation. Hence, alternative premedicants such as L-theanine and GABA will have a widespread appeal and are safer. The primary objective was to study and compare the effects of L-theanine and GABA on preoperative anxiety, sedation, and cognition in patients posted for major elective surgeries. The secondary objective was to study adverse reactions. Material and Methods A total of 168 patients aged between 18 and 55 years, belonging to the American Society of Anesthesiologists physical status class I and II, and satisfying all inclusion criteria were randomly divided into three groups that received either oral L-theanine, oral GABA, or oral alprazolam 0.25 mg. The anxiety score, sedation score, and psychomotor and cognitive performance scores were noted 60 minutes before and after the administration of the drugs. Results Alprazolam produced more sedation than GABA and L-theanine (P = 0.0001). Psychomotor and cognitive functions improved with L-theanine and GABA (P = 0.0001) and decreased with alprazolam (P = 0.0001). Conclusion GABA and L-theanine result in effective preoperative anxiolysis with minimal sedation and improvement of cognitive skills.
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Affiliation(s)
- Shrinidhi S. Deshpande
- Department of Anaesthesiology, Karnataka Institute of Medical Sciences (KIMS), Hubli, Karnataka, India
| | - Madhuri Kurdi
- Department of Anaesthesiology, Karnataka Institute of Medical Sciences (KIMS), Hubli, Karnataka, India
| | - Amrita Baiju
- Department of Anaesthesiology, Karnataka Institute of Medical Sciences (KIMS), Hubli, Karnataka, India
| | - A. S. Athira
- Department of Anaesthesiology, Karnataka Institute of Medical Sciences (KIMS), Hubli, Karnataka, India
| | - Athira G. Sarasamma
- Department of Anaesthesiology, Karnataka Institute of Medical Sciences (KIMS), Hubli, Karnataka, India
| | - Arunima K. Gangadharan
- Department of Anaesthesiology, Karnataka Institute of Medical Sciences (KIMS), Hubli, Karnataka, India
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Han Z, Wang L, Zhu H, Tu Y, He P, Li B. Uncovering the effects and mechanisms of tea and its components on depression, anxiety, and sleep disorders: A comprehensive review. Food Res Int 2024; 197:115191. [PMID: 39593401 DOI: 10.1016/j.foodres.2024.115191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2024] [Revised: 09/29/2024] [Accepted: 10/11/2024] [Indexed: 11/28/2024]
Abstract
Depression, anxiety and sleep disorders are prevalent psychiatric conditions worldwide, significantly impacting the physical and mental well-being of individuals. The treatment of these conditions poses various challenges, including limited efficacy and potential side effects. Tea, a globally recognized healthful beverage, contains a variety of active compounds. Studies have shown that consuming tea or ingesting its certain active ingredients have a beneficial impact on the mental health issues mentioned above. While the effects of tea on physical health are well-documented, there remains a gap in our systematic understanding of its impact on mental health. This article offers a thorough overview of animal, clinical, and epidemiological studies examining tea and its components in the treatment of depression, anxiety, and sleep disorders, and summarizes the associated molecular mechanisms. The active ingredients in tea, including L-theanine, γ-aminobutyric acid (GABA), arginine, catechins, theaflavins, caffeine, theacrine, and several volatile compounds, may help improve depression, anxiety, and sleep disorders. The underlying molecular mechanisms involve the regulation of neurotransmitters, including monoamines, GABA, and brain-derived neurotrophic factor (BDNF), as well as the suppression of oxidative stress and inflammation. Additionally, these ingredients may influence the microbiota-gut-brain (MGB) axis and the hypothalamic-pituitary-adrenal (HPA) axis. This review provides valuable insights into the effects and mechanisms by which tea and its components regulate depression, anxiety, and sleep disorders, laying the groundwork for further research into relevant mechanisms and the development of tea-based mental health products.
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Affiliation(s)
- Ziyi Han
- Department of Tea Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China
| | - Leyu Wang
- Department of Tea Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China
| | - Huanqing Zhu
- Department of Tea Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China
| | - Youying Tu
- Department of Tea Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China
| | - Puming He
- Department of Tea Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China
| | - Bo Li
- Department of Tea Science, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China.
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Lim IS. Effects of supplement L-theanine on cognitive anxiety, salivary alpha-amylase, and cortisol in archery competition. Phys Act Nutr 2024; 28:70-74. [PMID: 39934632 PMCID: PMC11811612 DOI: 10.20463/pan.2024.0034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2024] [Revised: 12/27/2024] [Accepted: 12/27/2024] [Indexed: 02/13/2025] Open
Abstract
PURPOSE Archery is a representative sport requiring high levels of concentration. Accordingly, assessing participants' physiological and psychological factors related to tension, anxiety, and stress represents a valuable resource for enhancing performance. This study examines the impact of L-theanine administration on archers' cognitive anxiety levels, salivary alpha-amylase (sAA), and salivary cortisol (sC) in archery competition. METHODS The study included 18 athletes from women's colleges who participated in the 50-meter individual competition at the 40th president's cup national archery competition in June 2023. Athletes' anxiety levels were assessed on a Likert scale, ranging from 1 "not at all" to 10 "extremely anxious." Saliva samples were collected 30, 20, and 10 minutes before and 20 minutes after the game. Repeated measures of the general linear model ANOVA were performed to compare the mean values of sAA and anxiety level. RESULTS Cognitive anxiety levels were significantly reduced in the treatment compared to the placebo group at 10 minutes before the game (p<.05); sAA levels were significantly reduced in the treatment group compared to the placebo group at 20 and 10 minutes before the game (pre-20 and pre-10, respectively); and sC levels were significantly reduced in the treatment compared to the placebo group at 10 minutes before the game (p<.05). CONCLUSION The findings demonstrate that L-theanine treatment is an efficacious intervention for reducing cognitive anxiety, sAA, and sC levels in sports. Therefore, it is recommended to alleviate competitive anxiety in sports requiring high concentration levels such as archery.
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Affiliation(s)
- In-Soo Lim
- Department of physical education, Changwon National University, Changwon, Republic of Korea
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10
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Unno K, Taguchi K, Matsuda T, Nakamura Y. Stress-Relieving Effects of Green Tea Depend on the Ratio of Its Special Ingredients and the Infusion Conditions. Molecules 2024; 29:4553. [PMID: 39407485 PMCID: PMC11477503 DOI: 10.3390/molecules29194553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2024] [Revised: 09/20/2024] [Accepted: 09/24/2024] [Indexed: 10/20/2024] Open
Abstract
Theanine, an amino acid unique to tea leaves, has been reported to exhibit stress-relieving effects. However, the stress-relieving effects of theanine (T) are greatly inhibited by caffeine (C) and epigallocatechin gallate (E), the main components of green tea, while being enhanced by arginine (A). Animal and clinical studies using matcha tea have shown that it can alleviate stress if the molar ratio of C and E against T and A (CE/TA) is less than 2. In general, the CE/TA ratio in tea leaves is reflected by the CE/TA ratio in the infused solution; however, it is not clear what infusion conditions would be expected to ensure a stress-relieving effect. In this study, to examine the stress-relieving effect of green-tea-infused solutions, the CE/TA ratio was measured under different infusion conditions. Furthermore, a study using a model solution consisting of C, E, T, and A revealed that a CE/TA ratio of at least less than 2 and a T content greater than 0.23 mM were required for stress reduction. Based on these results, we identified tea leaves and their infusion conditions that can be expected to reduce stress.
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Affiliation(s)
- Keiko Unno
- Tea Science Center, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan; (K.T.); (Y.N.)
| | - Kyoko Taguchi
- Tea Science Center, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan; (K.T.); (Y.N.)
| | - Tomoko Matsuda
- Mie Prefecture Agricultural Research Institute Green Tea Industry Flower and Planting Laboratory, 992-2 Tsubakise-cho, Kameyama City 519-0104, Japan;
| | - Yoriyuki Nakamura
- Tea Science Center, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan; (K.T.); (Y.N.)
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11
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Baba Y, Takihara T, Okamura N. Matcha Does Not Affect Electroencephalography during Sleep but May Enhance Mental Well-Being: A Randomized Placebo-Controlled Clinical Trial. Nutrients 2024; 16:2907. [PMID: 39275223 PMCID: PMC11397442 DOI: 10.3390/nu16172907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2024] [Revised: 08/23/2024] [Accepted: 08/28/2024] [Indexed: 09/16/2024] Open
Abstract
Although theanine in matcha improves sleep quality and cognitive function, the caffeine in green tea is thought to worsen sleep quality. Therefore, this study investigated the factors behind the observed improvements in subjective sleep quality in matcha. A placebo-controlled randomized double-blind parallel-group study was conducted on healthy Japanese men and women aged 27-64 years. After 4 weeks of consuming 2.7 g of matcha daily (containing 50.3 mg theanine, 301.4 mg catechins, and 71.5 mg caffeine), no significant differences were observed between the control and matcha groups on total sleep time, sleep latency, wake after sleep onset, or sleep efficiency measured by electroencephalography (EEG). However, the sleep questionnaire Oguri-Shirakawa-Azumi Sleep Inventory, the Middle-age and Aged version (OSA-MA), administered immediately after waking showed a trend toward increased satisfaction with sleep time (p < 0.1), and EEG measurements indicated significantly shortened wake-up times after waking with matcha intake (p < 0.05). The Beck Depression Inventory-II scores also tended to decrease (p < 0.1). The continuous intake of matcha may offer improved subjective sleep quality and emotional stability despite not offering significant changes in objective sleep parameters.
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Affiliation(s)
- Yoshitake Baba
- Central Research Institute, ITO EN, Ltd., 21 Mekami, Makinohara 421-0516, Shizuoka, Japan
| | - Takanobu Takihara
- Central Research Institute, ITO EN, Ltd., 21 Mekami, Makinohara 421-0516, Shizuoka, Japan
| | - Noritaka Okamura
- Department of Medical Technology, Faculty of Health Sciences, Ehime Prefectural University of Health Sciences, 543 Takoda, Tobe-cho 791-2101, Iyo-Gun, Japan
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12
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Moulin M, Crowley DC, Xiong L, Guthrie N, Lewis ED. Safety and Efficacy of AlphaWave ® L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Randomized, Double-Blind, Placebo-Controlled Trial. Neurol Ther 2024; 13:1135-1153. [PMID: 38758503 PMCID: PMC11263523 DOI: 10.1007/s40120-024-00624-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Accepted: 04/23/2024] [Indexed: 05/18/2024] Open
Abstract
BACKGROUND Prolonged periods of stress may lead to negative health consequences. AlphaWave® L-Theanine was safe and efficacious during an acute stress challenge. However, double-blind, placebo-controlled clinical trials investigating the longer term effects of L-theanine supplementation on stress are warranted. METHODS Thirty healthy adults (18-65 years) with moderate stress were randomized to AlphaWave® L-Theanine (400 mg L-theanine/day) or placebo (n = 15/group) for 28 days. Stress was assessed by salivary cortisol, Perceived Stress Scale (PSS) and Depression, Anxiety and Stress Scale-21; sleep was assessed by the Healthy People Sleep Quality Index and actigraphy device; cognition was assessed by Computerized Mental Performance Assessment System; mood was assessed by Profile of Mood States. All outcomes were measured at baseline, Days 14 and 28. Safety included vital signs, clinical chemistry, haematology and adverse events (AEs). RESULTS All AEs were resolved by the end of the study period or upon subsequent follow up, and out of range laboratory values and changes in vital signs were deemed not clinically relevant following AlphaWave® L-Theanine supplementation. Participants supplemented with AlphaWave® L-Theanine had decreases of 12.92% (p = 0.051) and 17.98% (p = 0.04) in PSS scores after 14 and 28 days, respectively, while those on placebo had respective decreases of 9.74% (p = 0.061) and 17.88% (p = 0.009). There were no significant differences between groups for change in salivary cortisol. The AlphaWave® L-Theanine group demonstrated decreased time asleep after 28 days and significantly reduced light sleep after 14 and 28 days compared to placebo (p ≤ 0.040). The AlphaWave® L-Theanine group significantly improved by 21.79% and 21.33% in Stroop test correct reaction time after 14 and 28 days, respectively, while those on placebo improved after 28 days only (p = 0.005). CONCLUSIONS AlphaWave® L-Theanine supplementation for 28 days was safe and significantly decreased perceived stress significantly decreased perceived stress and light sleep, improved sleep quality and enhanced cognitive attention in the studied population. Larger, randomized controlled trials with longer duration of AlphaWave® L-Theanine supplementation are warranted to reduce inter-individual variability and the potential placebo effect. TRIAL REGISTRATION ClinicalTrials.gov identifier, NCT05808595.
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Affiliation(s)
- Marc Moulin
- KGK Science Inc., 275 Dundas Street, Tower A, Suite A1605, London, ON, N6B 3L1, Canada
| | - David C Crowley
- KGK Science Inc., 275 Dundas Street, Tower A, Suite A1605, London, ON, N6B 3L1, Canada
| | - Lora Xiong
- Ethical Naturals, Inc., 2731 Fair Oaks Ave, Redwood City, CA, 94063, USA
| | - Najla Guthrie
- KGK Science Inc., 275 Dundas Street, Tower A, Suite A1605, London, ON, N6B 3L1, Canada
| | - Erin D Lewis
- KGK Science Inc., 275 Dundas Street, Tower A, Suite A1605, London, ON, N6B 3L1, Canada.
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13
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García-Niño WR, Correa F, Zúñiga-Muñoz AM, José-Rodríguez A, Castañeda-Gómez P, Mejía-Díaz E. L-theanine abates oxidative stress and mitochondrial dysfunction in myocardial ischemia-reperfusion injury by positively regulating the antioxidant response. Toxicol Appl Pharmacol 2024; 486:116940. [PMID: 38677602 DOI: 10.1016/j.taap.2024.116940] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/08/2024] [Accepted: 04/22/2024] [Indexed: 04/29/2024]
Abstract
L-theanine (L-THE), a non-protein amino acid isolated from Camelia sinensis, has antioxidant properties that could prevent oxidative damage and mitochondrial dysfunction generated by myocardial ischemia and reperfusion (I/R) injury. The present study aimed to identify the effects of pretreatment with L-THE in rat hearts undergoing I/R. Wistar rats received vehicle or 250 mg/Kg L-THE intragastrically for 10 days. On day 11, hearts were removed under anesthesia and exposed to I/R injury in the Langendorff system. Measurement of left ventricular developed pressure and heart rate ex vivo demonstrates that L-THE prevents I/R-induced loss of cardiac function. Consequently, the infarct size of hearts subjected to I/R was significantly decreased when L-THE was administered. L-THE also mitigated I/R-induced oxidative injury in cardiac tissue by decreasing reactive oxygen species and malondialdehyde levels, while increasing the activity of antioxidant enzymes, SOD and CAT. Additionally, L-THE prevents oxidative phosphorylation breakdown and loss of inner mitochondrial membrane potential caused by I/R, restoring oxygen consumption levels, increasing respiratory control and phosphorylation efficiency, as well as buffering calcium overload. Finally, L-THE modifies the expression of genes involved in the antioxidant response through the overexpression of SOD1, SOD2 and CAT; as well as the transcriptional factors PPARα and Nrf2 in hearts undergoing I/R. In conclusion, L-THE confers cardioprotection against I/R injury by preventing oxidative stress, protecting mitochondrial function, and promoting overexpression of antioxidant genes. More studies are needed to place L-THE at the forefront of cardiovascular research and recommend its therapeutic use.
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Affiliation(s)
- Wylly Ramsés García-Niño
- Department of Cardiovascular Biomedicine, National Institute of Cardiology Ignacio Chávez, Mexico City 14080, Mexico.
| | - Francisco Correa
- Department of Cardiovascular Biomedicine, National Institute of Cardiology Ignacio Chávez, Mexico City 14080, Mexico
| | - Alejandra María Zúñiga-Muñoz
- Department of Cardiovascular Biomedicine, National Institute of Cardiology Ignacio Chávez, Mexico City 14080, Mexico
| | - Aldo José-Rodríguez
- Department of Cardiovascular Biomedicine, National Institute of Cardiology Ignacio Chávez, Mexico City 14080, Mexico
| | - Patricio Castañeda-Gómez
- Department of Cardiovascular Biomedicine, National Institute of Cardiology Ignacio Chávez, Mexico City 14080, Mexico
| | - Edson Mejía-Díaz
- Department of Cardiovascular Biomedicine, National Institute of Cardiology Ignacio Chávez, Mexico City 14080, Mexico
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14
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Kurosaka C, Tagata C, Nakagawa S, Kobayashi M, Miyake S. Effects of green tea and roasted green tea on human responses. Sci Rep 2024; 14:8588. [PMID: 38615105 PMCID: PMC11016062 DOI: 10.1038/s41598-024-59383-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 04/10/2024] [Indexed: 04/15/2024] Open
Abstract
Our objective was to elucidate the effects of tea consumption on refreshment and stress reduction/recovery through examining the multiple associations among factors such as various physiological responses and task performance. Participants included 20 healthy young men who performed a mental arithmetic task while 11 physiological responses were measured. The experiments were conducted twice under different beverage consumption conditions on separate days. The mental arithmetic task was executed six times in 1 day; participants ingested hot water, green tea, or roasted green tea (hojicha) before each task. Several subjective assessments: subjective fatigue, stress, mental workload, and flow were evaluated after each task. The R-R intervals, heart rate variability spectral components, the Poincaré plot indices (SD1 and SD2) and plethysmogram amplitude tended to decrease during task periods compared to resting periods. Tissue blood volume/flow (TBV, TBF) and near-infrared spectroscopy responses (NIRS) were lower in the tea condition than in the hot water condition. By scrutinizing various indicators, we found that aromatic stimulation of Japanese tea beverages has the potential to induce positive effects, enhance mental task performance, promote refreshment, and alleviate feelings of fatigue. These positive effects were observed even in small quantities and within a short duration, mirroring responses observed in daily consumption.
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Affiliation(s)
- Chie Kurosaka
- Department of Human, Information and Life Sciences, School of Health Sciences, University of Occupational and Environmental Health, Japan, Kitakyushu, Fukuoka, Japan.
| | - Chika Tagata
- Central Research Institute, ITOEN, Ltd., Makinohara, Shizuoka, Japan
| | - Sae Nakagawa
- Central Research Institute, ITOEN, Ltd., Makinohara, Shizuoka, Japan
| | - Makoto Kobayashi
- Central Research Institute, ITOEN, Ltd., Makinohara, Shizuoka, Japan
| | - Shinji Miyake
- Graduate School of Science and Technology, Chitose Institute of Science and Technology, Chitose, Hokkaido, Japan
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15
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Jirakittayakorn N, Tamboon E, Mitrirattanakul S. Effect of 1% H 2O 2 on Three Salivary Stress Biomarkers, Cortisol, Alpha-Amylase, and sIgA. Int Dent J 2024; 74:343-351. [PMID: 37985342 PMCID: PMC10988260 DOI: 10.1016/j.identj.2023.10.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/17/2023] [Accepted: 10/19/2023] [Indexed: 11/22/2023] Open
Abstract
BACKGROUND Due to the COVID-19 pandemic, several associations worldwide have been recommending the use of 1% hydrogen peroxide solution as a preprocedural mouth rinse before dental treatments to reduce viral load in saliva. This protocol is also employed in stress studies, especially in the context of dental treatment that uses salivary biomarkers as an indicator. However, the effect of 1% hydrogen peroxide as mouth rinse on salivary biomarkers remains unclear. OBJECTIVE This study aims to investigate the effects of 1% hydrogen peroxide solution as a preprocedural mouth rinse on 3 salivary stress biomarkers-salivary cortisol, salivary secretory IgA, and salivary α-amylase-both on chemical influence and mechanical irrigation. MATERIALS AND METHODS Ninety healthy participants with confirmed negative Reverse Transcription Polymerase Chain Reaction results for COVID-19 at most 2 days prior to the experiment were included in this study. All participants were randomly allocated into 3 groups: experimental (1% hydrogen peroxide solution), positive control (distilled water), and negative control (no mouth rinse). Saliva samples were collected before and after mouth rinsing with the respective solutions. Salivary biomarkers were analysed using specific enzyme-linked immunosorbent assay kits. RESULTS Salivary cortisol and salivary α-amylase did not significantly differ before and after rinsing, whilst salivary sIgA levels decreased in all 3 groups. Nonetheless, there were no significant differences in the changes of these biomarkers across the 3 groups. CONCLUSIONS This study shows that using 1% hydrogen peroxide solution as a preprocedural mouth rinse for universal precaution does not alter the levels of these 3 salivary biomarkers.
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Affiliation(s)
- Nantawachara Jirakittayakorn
- Faculty of Dentistry, Mahidol University, Bangkok, Thailand; School of Dentistry, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand
| | - Eakapong Tamboon
- Department of Oral Biology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Somsak Mitrirattanakul
- Department of Masticatory Science, Faculty of Dentistry, Mahidol University, Bangkok Thailand.
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16
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Zhang W, Zhang D, Wang P, Li X, Wang Z, Chen Q, Huang J, Yu Z, Guo F, Liang P. Development of a SERS aptasensor for the determination of L-theanine using a noble metal nanoparticle-magnetic nanospheres composite. Mikrochim Acta 2024; 191:158. [PMID: 38409501 DOI: 10.1007/s00604-024-06245-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/01/2024] [Indexed: 02/28/2024]
Abstract
An ultrasensitive surface-enhanced Raman spectroscopy (SERS) aptamer sensor (aptasensor) using a noble metal nanoparticle-magnetic nanospheres composite was developed for L-theanine detection. It makes use of Fe3O4@Au MNPs and Au@Ag NPs embedded with the Raman reporter 4-mercaptobenzoic acid (4MBA). Au@4MBA@Ag NPs modified by aptamer and Fe3O4@Au MNPs modified by cDNA created the aptasensor with the strongest Raman signal of 4MBA through the specific binding of the aptamer. With the preferred binding of L-theanine aptamer to L-theanine, Au@4MBA@Ag NPs were released from Fe3O4@Au MNPs, causing a linear decrease in SERS intensity to achieve the SERS detection of the L-theanine. The SERS peak of 4MBA at 1078 cm-1 was used for quantitative determination. SERS intensity showed a good log-linear relationship within the range 10-10 to 10-6 M of L-theanine. The aptasensor has a high selectivity for L-theanine compared with other twelve tested analytes. Hence, this aptasensor is a promising analytical tool for L-theanine detection. The developed method was applied to the analysis of real samples, demonstrating excellent performance. The comparison with the standard liquid chromatography mass spectrometry method showed an error within 20%.
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Affiliation(s)
- Wei Zhang
- College of Optical and Electronic Technology, China Jiliang University, Hangzhou, 310018, China
| | - De Zhang
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Pu Wang
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xiaoming Li
- College of Optical and Electronic Technology, China Jiliang University, Hangzhou, 310018, China
| | - Zhetao Wang
- College of Optical and Electronic Technology, China Jiliang University, Hangzhou, 310018, China
| | - Qiang Chen
- College of Metrology and Measurement Engineering, China Jiliang University, Hangzhou, 310018, China
| | - Jie Huang
- State Key Laboratory of Rice Biology, Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou, 310029, China
| | - Zhi Yu
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Fei Guo
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Pei Liang
- College of Optical and Electronic Technology, China Jiliang University, Hangzhou, 310018, China.
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17
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Bolouri-Roudsari A, Baghani M, Askari K, Mazaheri S, Haghparast A. The integrative role of orexin-1 and orexin-2 receptors within the hippocampal dentate gyrus in the modulation of the stress-induced antinociception in the formalin pain test in the rat. Behav Pharmacol 2024; 35:14-25. [PMID: 37578388 DOI: 10.1097/fbp.0000000000000737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
The stressful experiences, by triggering a cascade of hormonal and neural changes, can produce antinociception commonly referred to as stress-induced antinociception (SIA). Orexin neuropeptides have an essential role in stress responses and pain modulation. The dentate gyrus receives orexinergic projections and has been shown to be involved in pain processing. The current study investigated the possible role of orexin-1 and orexin-2 receptors (OX1r and OX2r, respectively) within the dentate gyrus in SIA in a rat model of formalin-induced pain behavior in one hind paw. Male Wistar rats weighing 230-250 g underwent stereotaxic surgery and a cannula was implanted in their brains, above the dentate gyrus region. Either SB334867 or TCS OX2 29 (OX1r and OX2r antagonists, respectively) was microinjected into the dentate gyrus region at a range of doses at 1, 3, 10, and 30 nmol (control group received DMSO 12% as vehicle), 5 min before the forced swim stress (FSS) exposure. The formalin test was performed to assess pain-related behaviors. The results indicated that FSS exposure relieves pain-related behavior in the early and late phases of the formalin test. Blockade of intra-dentate gyrus OX1 or OX2 receptors reduced the antinociceptive responses induced by FSS in the formalin test, with more impact during the late phase. Our findings support the potential role of intra-dentate gyrus orexin receptors as target sites of orexin neurons in painful and stressful situations. Therefore, understanding the exact mechanisms of SIA and the role of the orexinergic system in this phenomenon can lead to identifying the strategies to guide future research and offer a new approach to discovering new pain therapeutic agents.
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Affiliation(s)
- Arad Bolouri-Roudsari
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University
| | - Matin Baghani
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University
| | | | - Sajad Mazaheri
- Neurophysiology Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences
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18
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Nieman KM, Zhu Y, Tucker M, Koecher K. The Role of Dietary Ingredients in Mental Energy - A Scoping Review of Randomized Controlled Trials. JOURNAL OF THE AMERICAN NUTRITION ASSOCIATION 2024; 43:167-182. [PMID: 37561965 DOI: 10.1080/27697061.2023.2244031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 06/09/2023] [Accepted: 07/30/2023] [Indexed: 08/12/2023]
Abstract
Low mental energy can contribute to decreased productivity, altered life balance, decreased physical performance, and ultimately affect quality of life. As such, there is a great demand for food and beverage products that positively impact mental energy. Numerous products claim to alter mental energy making continued review of the scientific evidence critical. The objective of this study was to conduct a scoping review of randomized controlled trials to evaluate the effect of 18 dietary ingredients on mental energy outcomes in adults without severe disease. Methods: A literature search, completed using PubMed, resulted in the identification of 2261 articles, 190 of which met eligibility from initial abstract review. Full-text review was completed on the 190 studies which resulted in 101 articles that fully met eligibility for inclusion in this study. The search strategy for two ingredients did not yield any eligible studies, leaving studies for 16 ingredients that were extracted and summarized by reported significantly improved outcomes for cognition, mood and perceived feelings, and sleep assessments. The preliminary results for several dietary ingredients directionally suggested a mental energy benefit (≥20% of outcomes), including ashwagandha, chamomile, dark chocolate, ginseng, green tea, lavender, lion's mane mushroom, maca, tart cherries, turmeric, and valerian root. The results of this scoping review suggest that of the 16 dietary ingredients reviewed, 11 may be promising for further exploration on their potential benefits in supporting mental energy. Given consumer demand and market growth for food and beverage products that positively impact mental energy; continued efforts in assessment method alignment and additional evaluation in well-designed trials is warranted.KEY TEACHING POINTSOf the 16 dietary ingredients reviewed, 11 (ashwagandha, chamomile, dark chocolate, ginseng, green tea, lavender, lion's mane mushroom, maca, melatonin foods, turmeric, and valerian root) may be promising for further exploration on their potential mental energy benefits.Dark chocolate, ginseng, ashwagandha, and lion's mane mushroom were the most promising ingredients for further evaluation in the cognition domain of the ingredients evaluated.Turmeric, maca, lavendar, and ashwagandha were the most promising ingredients for further evaluation in the mood and perceived feelings domain of the ingredients evaluated.Ashwagandha, chamomile, green tea, melatonin foods, valerian root were the most promising ingredients for further evaluation in the sleep domain of the ingredients evaluated.Additional, well-designed, consistent, clinical trials and systematic reviews are warranted as the challenge of heterogeneity in mental energy study design remains.
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Affiliation(s)
| | - Yong Zhu
- Bell Institute of Health and Nutrition, General Mills, Inc, Minneapolis, Minnesota, USA
| | - Michelle Tucker
- Bell Institute of Health and Nutrition, General Mills, Inc, Minneapolis, Minnesota, USA
| | - Katie Koecher
- Bell Institute of Health and Nutrition, General Mills, Inc, Minneapolis, Minnesota, USA
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19
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McAllister MJ, Martaindale MH, Dillard CC, McCullough R. Impact of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality based active shooter training drill. Stress 2024; 27:2375588. [PMID: 38975711 DOI: 10.1080/10253890.2024.2375588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Accepted: 06/25/2024] [Indexed: 07/09/2024] Open
Abstract
Ingestion of L-theanine and L-tyrosine has been shown to reduce salivary stress biomarkers and improve aspects of cognitive performance in response to stress. However, there have been no studies to concurrently examine the impact of both L-theanine and L-tyrosine ingestion during a mental stress challenge (MSC) involving a brief cognitive challenge and a virtual reality based active shooter training drill. Thus, the purpose of this study was to determine the impact of ingestion of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality active shooter drill and cognitive challenge. The cognitive challenge involved a Stroop challenge and mental arithmetic. Eighty subjects (age = 21 ± 2.6 yrs; male = 46; female = 34) were randomly assigned L-tyrosine (n = 28; 2000 mg), L-theanine (n = 25; 200 mg), or placebo (n = 27) prior to MSC exposure. Saliva samples, state-anxiety inventory (SAI) scales, and heart rate (HR) were collected before and after exposure to the MSC. Saliva was analyzed for stress markers α-amylase (sAA) and secretory immunoglobulin A (SIgA). The MSC resulted in significant increases in sAA, SIgA, HR, and SAI. Ingestion of L-theanine and L-tyrosine did not impact markers of stress. However, the L-tyrosine treatment demonstrated significantly lower missed responses compared to the placebo treatment group during the Stroop challenge. These data demonstrate that ingestion of L-theanine or L-tyrosine does not impact markers of stress in response to a MSC but may impact cognitive performance. This study was pre-registered as a clinical trial ("Impact of supplements on stress markers": NCT05592561).
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Affiliation(s)
- Matthew J McAllister
- Metabolic & Applied Physiology Laboratory, Department of Health & Human Performance, Texas State University, San Marcos, TX, USA
| | | | - Courtney C Dillard
- Metabolic & Applied Physiology Laboratory, Department of Health & Human Performance, Texas State University, San Marcos, TX, USA
| | - Rory McCullough
- Metabolic & Applied Physiology Laboratory, Department of Health & Human Performance, Texas State University, San Marcos, TX, USA
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20
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Yilmaz U, Buzdagli Y, Polat ML, Bakir Y, Ozhanci B, Alkazan S, Ucar H. Effect of single or combined caffeine and L-Theanine supplementation on shooting and cognitive performance in elite curling athletes: a double-blind, placebo-controlled study. J Int Soc Sports Nutr 2023; 20:2267536. [PMID: 37815006 PMCID: PMC10566444 DOI: 10.1080/15502783.2023.2267536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 10/03/2023] [Indexed: 10/11/2023] Open
Abstract
PURPOSE Previous studies have investigated the effect of single or combined caffeine (CAF) and L-theanine (THE) intake on attention performance. However, its effect on shooting performance and cognitive performance in a sport is unknown. The aim of this study was to investigate the hypothesis "Does single or combined CAF and THE supplementation have an effect on shooting and cognitive performance in elite curling athletes?." It is predicted that over the next decade, studies based on nutritional ergogenic supplements in the developing sport of curling will continue to increase, leading to a significant increase in studies examining the effects of CAF and THE supplementation, alone or in combination, on throwing and cognitive performance in elite curling athletes. METHODS In this double-blind, randomized controlled crossover study, twenty-two elite national curling athletes (age 20.20 ± 1.61 and sports age 6.20 ± 0.51 years, height 174.10 ± 7.21 cm, BMI 21.80 ± 3.47 kg/m2) were randomly assigned to CAF (6 mg/kg single dose CAF), THE (6 mg/kg single dose THE), CAF*THE (6 mg/kg CAF and 6 mg/kg THE combined) and PLA (400 mg maltodextrin) groups at each of four sessions. 60 minutes after taking the supplement, the athletes were first given the Stroop test and then asked to shoot. RESULTS Our main findings have shown that the performance of athletes in guard (F=3.452, P < .001, ηp2 = .842), draw (F=1.647, P < .001, ηp2 = .485), and take-out (F=3.121, P < .001, ηp2 = .743) shot styles significantly improved when comparing the combined intake of CAF and THE to the PLA. Regarding cognitive performance evaluation through the Stroop test, during the NR task (F=4.743, P = .001, ηp2 = .653), the combined intake of CAF and THE significantly improved reaction times compared to the intake of single CAF, THE, or PLA. The best reaction times during the CR and ICR (respectively; F=2.742, P = .004, ηp2 = .328; F = 1.632, P < .001, ηp2 = .625) tasks were achieved with the combined CAF and THE intake, showing a significant improvement compared to PLA. During the NER (F=2.961, P < .001, ηp2 = .741), task, the combined intake of CAF and THE significantly improved error rates compared to the intake of CAF, THE, or PLA single. The best accuracy rates during the CER and ICER (respectively; F=4.127, P < .001, ηp2 = .396; F=3.899, P < .001, ηp2 = .710) tasks were achieved with the combined CAF and THE intake, leading to a significant reduction in error rates compared to PLA. Based on these findings, it has been demonstrated in this study that the best shooting scores and cognitive performance were achieved, particularly with the combined intake of CAF and THE. CONCLUSIONS Based on these findings, it has been demonstrated in this study that the best shooting scores and cognitive performance were achieved, particularly with the combined intake of CAF and THE. The combined use of these supplements has been found to be more effective on shooting and cognitive performance than their single use.
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Affiliation(s)
- Umut Yilmaz
- Hakkâri University, Department of Physical Education and Sports, Faculty of Education, Hakkâri, Turkey
| | - Yusuf Buzdagli
- Erzurum Technical University, Department of Coaching Education, Faculty of Sport Sciences, Erzurum, Turkey
| | | | - Yusuf Bakir
- Erzurum Technical University, Institute of Health Sciences, Erzurum, Turkey
| | - Burak Ozhanci
- Erzurum Technical University, Institute of Health Sciences, Erzurum, Turkey
| | - Sena Alkazan
- Erzurum Technical University, Institute of Health Sciences, Erzurum, Turkey
| | - Halil Ucar
- Atatürk University, Institute of Winter Sports and Sport Sciences, Erzurum, Turkey
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21
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Minné D, Stromin J, Docrat T, Engel-Hills P, Marnewick JL. The effects of tea polyphenols on emotional homeostasis: Understanding dementia risk through stress, mood, attention & sleep. Clin Nutr ESPEN 2023; 57:77-88. [PMID: 37739736 DOI: 10.1016/j.clnesp.2023.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 04/18/2023] [Accepted: 06/11/2023] [Indexed: 09/24/2023]
Abstract
Decades of research provide evidence that certain phytochemicals in tea (Camellia sinensis) and other herbal beverages are protective against the development of sporadic types of dementia in later life. Since tea drinking is an economical and widely adopted social-cultural practice across all age groups, it is an ideal product to target in designing low-cost dietary interventions for Alzheimer's Disease (AD), the most prevalent form of dementia. In this review, we focus on the protective roles of tea-derived polyphenols and other phytochemicals on mood, the stress response, attention, and sleep, in keeping with the perspective that many early neuropathological events in AD may stem, in part, from allostatic overload. This approach aligns with the perspective that many forms of dementia, including AD, begin to take root in the brain decades prior to symptom onset, underscoring the need for early uptake of accessible and viable lifestyle interventions. The findings reviewed here suggest that consuming green and oolong tea can improve mood and reduce overall stress. However, given the caffeine content in tea and its association with stress reactivity, the effects of daily whole tea consumption on the emotional state are likely dose-dependent with an inverted-U relationship to wellbeing. Plant-based beverages that are to be consumed in high daily quantities for health purposes and which are naturally free of caffeine, such as Rooibos, may be more appropriate as a dietary supplement for managing emotional regulation over the lifetime.
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Affiliation(s)
- Donné Minné
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa; Health and Wellness Sciences Faculty, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Juliet Stromin
- Psychology Department, University of Cape Town, Lover's Walk, Rondebosch, Cape Town, 7700, South Africa.
| | - Taskeen Docrat
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Penelope Engel-Hills
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa; Health and Wellness Sciences Faculty, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Jeanine L Marnewick
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
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22
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Nematizadeh M, Ghorbanzadeh H, Moghaddam HS, Shalbafan M, Boroon M, Keshavarz-Akhlaghi AA, Akhondzadeh S. L-theanine combination therapy with fluvoxamine in moderate-to-severe obsessive-compulsive disorder: A placebo-controlled, double-blind, randomized trial. Psychiatry Clin Neurosci 2023; 77:478-485. [PMID: 37169515 DOI: 10.1111/pcn.13565] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 04/19/2023] [Accepted: 05/08/2023] [Indexed: 05/13/2023]
Abstract
AIM The main aim of this study was to investigate the additional effects of L-theanine, an amino acid in tea and an analog of glutamate with neuroprotective and anti-depressant properties, on obsessive-compulsive disorder (OCD) symptoms in combination with fluvoxamine. METHODS Patients from either sex aged between 18 and 60 years diagnosed with OCD, based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), who had a Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score of more than 21 were enrolled in a double-blinded, parallel-group, placebo-controlled, clinical trial of 10 weeks to receive either L-theanine (100 mg twice daily) and fluvoxamine (100 mg daily initially followed by 200 mg daily after week 5) or placebo and fluvoxamine. The primary outcome of interest in this study was the Y-BOCS total score decrease from baseline. RESULTS From a total of 95 evaluated patients, 50 completed our study; 30 were randomly assigned to each group. Multivariate analysis (ANOVA) showed a significant effect of time× $$ \times $$ treatment for L-theanine in obsession subscale (F = 5.51, P = 0.008) of the Y-BOCS score but not in the total and compulsion scores. Our results showed significantly more improvement in obsession subscale scores in L-theanine compared to placebo group (P = 0.007, Cohen's d = 0.82). Also, total Y-BOCS scores were lower in L-theanine compared to placebo group at week 5 (P = 0.039, Cohen's d = 0.60) and 10 (P = 0.008, Cohen's d = 0.80). However, there was no significant between-group differences in compulsion subscale scores. Complete response was also more frequent in the L-theanine group (P = 0.0001). CONCLUSION Findings in this study suggest L-theanine as a relatively safe and effective adjuvant therapy for moderate to severe OCD.
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Affiliation(s)
- Mehran Nematizadeh
- Psychiatric Research Center, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Ghorbanzadeh
- Psychiatric Research Center, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Sanjari Moghaddam
- Psychiatric Research Center, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammadreza Shalbafan
- Mental Health Research Center, Psychosocial Health Research Institute (PHRI), Department of Psychiatry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mahsa Boroon
- Mental Health Research Center, Psychosocial Health Research Institute (PHRI), Department of Psychiatry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Amir-Abbas Keshavarz-Akhlaghi
- Mental Health Research Center, Psychosocial Health Research Institute (PHRI), Department of Psychiatry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Shahin Akhondzadeh
- Psychiatric Research Center, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, Tehran, Iran
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23
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Zahar S, De Longis E, Hudry J. Revealing the Acute Effects of Dietary Components on Mood and Cognition: The Role of Autonomic Nervous System Responses. Brain Sci 2023; 13:1177. [PMID: 37626533 PMCID: PMC10452653 DOI: 10.3390/brainsci13081177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/01/2023] [Accepted: 08/01/2023] [Indexed: 08/27/2023] Open
Abstract
A growing body of literature suggests dietary components can support mood and cognitive function through the impact of their bioactive or sensorial properties on neural pathways. Of interest, objective measures of the autonomic nervous system-such as those regulating bodily functions related to heartbeat and sweating-can be used to assess the acute effects of dietary components on mood and cognitive function. Technological advancements in the development of portable and wearable devices have made it possible to collect autonomic responses in real-world settings, creating an opportunity to study how the intake of dietary components impacts mood and cognitive function at an individual level, day-to-day. In this paper, we aimed to review the use of autonomic nervous system responses such as heart rate or skin galvanic response to investigate the acute effects of dietary components on mood and cognitive performance in healthy adult populations. In addition to examining the existing methodologies, we also propose new state-of-the-art techniques that use autonomic nervous system responses to detect changes in proxy patterns for the automatic detection of stress, alertness, and cognitive performance. These methodologies have potential applications for home-based nutrition interventions and personalized nutrition, enabling individuals to recognize the specific dietary components that impact their mental and cognitive health and tailor their nutrition accordingly.
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Affiliation(s)
- Sélima Zahar
- Brain Health Department, Nestlé Institute of Health Sciences, Nestlé Research, Société des Produits Nestlé S.A., 1000 Lausanne, Switzerland; (E.D.L.); (J.H.)
- Center for Neuroprosthetics, Neuro-X Institute, École Polytechnique Fédérale De Lausanne (EPFL), 1202 Geneva, Switzerland
| | - Evelina De Longis
- Brain Health Department, Nestlé Institute of Health Sciences, Nestlé Research, Société des Produits Nestlé S.A., 1000 Lausanne, Switzerland; (E.D.L.); (J.H.)
| | - Julie Hudry
- Brain Health Department, Nestlé Institute of Health Sciences, Nestlé Research, Société des Produits Nestlé S.A., 1000 Lausanne, Switzerland; (E.D.L.); (J.H.)
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24
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Alkhlaif Y, El-Halawany M, Toma W, Park A, Hamouda AK, Damaj MI. L-theanine attenuates nicotine reward and withdrawal signs in mice. Neurosci Lett 2023; 807:137279. [PMID: 37105354 PMCID: PMC10204724 DOI: 10.1016/j.neulet.2023.137279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 04/29/2023]
Abstract
BACKGROUND L-theanine, 2-amino-4-(ethylcarbamoyl) butyric acid, an amino acid detected in green tea leaves, is used as a dietary supplement to attenuate stress and enhance mood and cognition. Furthermore, L-theanine induces anxiolytic effects in humans. Recently, L-theanine was reported to reduce morphine physical dependence in primates, suggesting the potential usefulness of L-theanine for drug dependence intervention. OBJECTIVE The aim of this study is to determine whether L-theanine attenuates nicotine-withdrawal (somatic and affective signs) and nicotine reward in mice. We also investigated the effects of L-theanine on nicotinic receptors binding and function. METHODS ICR male mice rendered dependent to nicotine through implanted subcutaneous osmotic minipumps for 14 days undertook precipitated nicotine withdrawal by mecamylamine on day 15. Anxiety-like behaviors using LDB, somatic signs observation and hot plate latency were assessed consecutively after treatment with L-theanine. Furthermore, we examined the effect of L-theanine on acute nicotine responses and nicotine conditioned reward in mice and on expressed nicotinic receptors in oocytes. KEY FINDINGS L-theanine reduced in a dose-dependent manner anxiety-like behavior, hyperalgesia and somatic signs during nicotine withdrawal. Also, L-theanine decreased the nicotine CPP, but it did not affect the acute responses of nicotine. Finally, L-theanine did not alter the binding or the function of expressed α4β2 and α7 nAChRs. CONCLUSION Our results support the potential of L-theanine as a promising candidate for treating nicotine dependence.
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Affiliation(s)
- Yasmin Alkhlaif
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, United States
| | - Medhat El-Halawany
- Department of Pharmaceutical Sciences and Health Outcomes, College of Pharmacy, The University of Texas at Tyler, Tyler, TX, United States
| | - Wisam Toma
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, United States
| | - Abigail Park
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, United States
| | - Ayman K Hamouda
- Department of Pharmaceutical Sciences and Health Outcomes, College of Pharmacy, The University of Texas at Tyler, Tyler, TX, United States
| | - M Imad Damaj
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, United States.
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25
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Zhou Y, He Y, Zhu Z. Understanding of formation and change of chiral aroma compounds from tea leaf to tea cup provides essential information for tea quality improvement. Food Res Int 2023; 167:112703. [PMID: 37087269 DOI: 10.1016/j.foodres.2023.112703] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 03/08/2023] [Accepted: 03/14/2023] [Indexed: 03/19/2023]
Abstract
Abundant secondary metabolites endow tea with unique quality characteristics, among which aroma is the core component of tea quality. The ratio of chiral isomers of aroma compounds greatly affects the flavor of tea leaves. In this paper, we review the progress of research on chiral aroma compounds in tea. With the well-established GC-MS methods, the formation of, and changes in, the chiral configuration of tea aroma compounds during the whole cycle of tea leaves from the plant to the tea cup has been studied in detail. The ratio of aroma chiral isomers varies among different tea varieties and finished teas. Enzymatic reactions involving tea aroma synthases and glycoside hydrolases participate the formation of aroma compound chiral isomers during tea tree growth and tea processing. Non-enzymatic reactions including environmental factors such as high temperature and microbial fermentation involve in the change of aroma compound chiral isomers during tea processing and storage. In the future, it will be interesting to determine how changes in the proportions of chiral isomers of aroma compounds affect the environmental adaptability of tea trees; and to determine how to improve tea flavor by modifying processing methods or targeting specific genes to alter the ratio of chiral isomers of aroma compounds.
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Affiliation(s)
- Ying Zhou
- Hainan Institute, Zhejiang University, Yazhou District, Sanya 572025, China.
| | - Yunchuan He
- Hainan Institute, Zhejiang University, Yazhou District, Sanya 572025, China; College of Agriculture and Biotechnology, Zhejiang University, Xihu District, Hangzhou 310030, China
| | - Zengrong Zhu
- Hainan Institute, Zhejiang University, Yazhou District, Sanya 572025, China; College of Agriculture and Biotechnology, Zhejiang University, Xihu District, Hangzhou 310030, China
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26
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Unno K, Taguchi K, Konishi T, Ozeki M, Nakamura Y. Theanine, a Tea-Leaf-Specific Amino Acid, Alleviates Stress through Modulation of Npas4 Expression in Group-Housed Older Mice. Int J Mol Sci 2023; 24:ijms24043983. [PMID: 36835393 PMCID: PMC9962395 DOI: 10.3390/ijms24043983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/03/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023] Open
Abstract
Group rearing is a common housing condition, but group-housed older mice show increased adrenal hypertrophy, a marker of stress. However, the ingestion of theanine, an amino acid unique to tea leaves, suppressed stress. We aimed to elucidate the mechanism of theanine's stress-reducing effects using group-reared older mice. The expression of repressor element 1 silencing transcription factor (REST), which represses excitability-related genes, was increased in the hippocampus of group-reared older mice, whereas the expression of neuronal PAS domain protein 4 (Npas4), which is involved in the regulation of excitation and inhibition in the brain, was lower in the hippocampus of older group-reared mice than in same-aged two-to-a-house mice. That is, the expression patterns of REST and Npas4 were found to be just inversely correlated. On the other hand, the expression levels of the glucocorticoid receptor and DNA methyltransferase, which suppress Npas4 transcription, were higher in the older group-housed mice. In mice fed theanine, the stress response was reduced and Npas4 expression tended to be increased. These results suggest that Npas4 expression was suppressed by the increased expression of REST and Npas4 downregulators in the group-fed older mice, but that theanine avoids the decrease in Npas4 expression by suppressing the expression of Npas4 transcriptional repressors.
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Affiliation(s)
- Keiko Unno
- Tea Science Center, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
- Correspondence:
| | - Kyoko Taguchi
- Tea Science Center, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Tomokazu Konishi
- Faculty of Bioresources Sciences, Akita Prefectural University, Shimoshinjo Nakano, Akita 010-0195, Japan
| | - Makoto Ozeki
- Taiyo Kagaku Co., Ltd., 1-3 Takaramachi, Yokkaichi 510-0844, Japan
| | - Yoriyuki Nakamura
- Tea Science Center, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
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27
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Torabynasab K, Shahinfar H, Payandeh N, Jazayeri S. Association between dietary caffeine, coffee, and tea consumption and depressive symptoms in adults: A systematic review and dose-response meta-analysis of observational studies. Front Nutr 2023; 10:1051444. [PMID: 36845051 PMCID: PMC9947483 DOI: 10.3389/fnut.2023.1051444] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 01/17/2023] [Indexed: 02/11/2023] Open
Abstract
Background Recent studies have reported an association between dietary caffeine intake (coffee and tea) and the presence of depressive symptoms. However, the findings are not conclusive. Purpose This study aimed to examine the correlation between the consumption of dietary caffeine (coffee and tea) and the presence of depressive symptoms in adults. Methods PubMed and Scopus databases were searched until December 2021. Two investigators analyzed data from identified studies and rated the quality of the evidence using the GRADE approach. Using the random-effects models, we estimated the relative risks (RRs) and 95% confidence intervals (CIs). We also modeled the dose-response associations through a one-stage, weighted mixed-effects meta-analysis. Results A total of 29 eligible studies included a total of 422,586 participants. On comparing the highest with the lowest category in cohort studies, we identified an inverse association between the intake of coffee and depressive symptoms (RR: 0.89, 95%CI: 0.82-0.95; I2 = 63.7%, GRADE = low). There was a 4% reduction in the risk of depression associated with an increase in coffee intake of 240 ml/day (RR: 0.96, 95%CI: 0.95, 0.98; I2 = 22.7%). By comparing the highest category with the lowest category in cohort studies, we discovered that caffeine intake was inversely associated with depressive symptoms (RR: 0.86, 95%CI: 0.79, 0.93; I2 = 0.0%, GRADE = moderate). Based on our data analysis, no correlation exists between tea consumption and depressive symptoms. Conclusion According to our findings, coffee and dietary caffeine may have a protective effect against the development of depression. However, no evidence suggesting a link between tea consumption and reduced depressive symptoms has been found. Therefore, further longitudinal studies are needed to substantiate the causal relationship between coffee, tea, and caffeine and the risk of depression.
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Affiliation(s)
- Kimia Torabynasab
- Student Research Committee, Iran University of Medical Sciences, Tehran, Iran
- Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Hossein Shahinfar
- Student Research Committee, Iran University of Medical Sciences, Tehran, Iran
- Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Nastaran Payandeh
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Shima Jazayeri
- Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
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Matcha Tea Powder's Antidepressant-like Effect through the Activation of the Dopaminergic System in Mice Is Dependent on Social Isolation Stress. Nutrients 2023; 15:nu15030581. [PMID: 36771286 PMCID: PMC9921318 DOI: 10.3390/nu15030581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/02/2023] [Accepted: 01/17/2023] [Indexed: 01/24/2023] Open
Abstract
Matcha tea powder is believed to have various physiological benefits; however, its detailed mechanism of action has been poorly understood. Here, we investigated whether the mental state of mice, due to social isolation stress, affects the antidepressant-like effect of Matcha tea powder by using the tail suspension test. Oral administration of Matcha tea powder reduced the duration of immobility in the stress-susceptible C57BL/6J strain, but not in BALB/c strain. In C57BL/6J mice, SCH23390, a dopamine D1 receptor blocker, prevented Matcha tea powder from exerting its antidepressant-like effect. Matcha tea powder also increased the number of c-Fos-positive cells in the prefrontal cortex (PFC) region and the nucleus accumbens (NAc) region in C57BL/6J mice, but not in BALB/c mice. In contrast, Matcha tea powder did not change the number of c-Fos-positive cells in the ventral tegmental area (VTA) region. Notably, C57BL/6J mice with a shorter immobility time had a higher number of c-Fos-positive cells in the PFC, NAc, and VTA regions. However, no such correlation was observed in the stress-tolerant BALB/c mice. These results suggest that Matcha tea powder exerts an antidepressant-like effect through the activation of the dopaminergic system including the PFC-NAc-VTA circuit and that mental states are important factors affecting the physiological benefits of Matcha tea powder.
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Furushima D, Sugiyama I, Nomura Y, Unno K, Yamada H. Effect of Combined Ingestion of L-Theanine and L-Arginine for Short-Term Psychological Stress in Young Adults: A Randomized Placebo-Controlled Study. J Nutr Sci Vitaminol (Tokyo) 2022; 68:540-546. [PMID: 36596553 DOI: 10.3177/jnsv.68.540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
l-Theanine, the most abundant amino acid component in green tea, has anti-stress effects and refreshes the mental state. A recent study demonstrated that l-arginine, the second most abundant amino acid in green tea, might enhance the anti-stress effects of l-theanine. The aim of this study was to evaluated the effects of combined ingestion of l-theanine and l-arginine on psychological stress in humans. A randomized placebo-controlled trial was conducted including 120 healthy young adults (mean age 22.4 y, 63.3% female). Subjects were randomly assigned to theanine (200 mg l-theanine), combined theanine/arginine (200 mg l-theanine, 50 mg l-arginine), or placebo groups. After consuming a test beverage, we administered a stress-loading test (Uchida-Kraepelin performance test) and performed salivary alpha-amylase activity (sAA) measurements to assess the physiological stress response at 0 min (immediately after), 5 min, and 15 min. The changes in sAA at 15 min after the stress-loading test were -2.75 (11.2) kIU/L in the theanine/arginine group, -0.40 (11.5) kIU/L in the theanine group, and 6.95 (18.6) kIU/L in the placebo group. The values in the theanine/arginine (p=0.007) and theanine (p=0.02) groups differed significantly from those in the placebo group. However, the difference between theanine/arginine and theanine groups, was not statistically significant (p=0.74). From this study, no clear conclusion could be drawn regarding the potentiating effect of theanine and arginine combined ingestion on anti-stress effects in human.
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Affiliation(s)
- Daisuke Furushima
- Graduate School of Health Sciences, Kagoshima University.,Department of Drug Evaluation and Informatics, University of Shizuoka Graduate School of Pharmaceutical Sciences
| | - Ibuki Sugiyama
- Department of Drug Evaluation and Informatics, University of Shizuoka Graduate School of Pharmaceutical Sciences
| | - Yuzuki Nomura
- Department of Drug Evaluation and Informatics, University of Shizuoka Graduate School of Pharmaceutical Sciences
| | - Keiko Unno
- Tea Science Center, Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka
| | - Hiroshi Yamada
- Department of Drug Evaluation and Informatics, University of Shizuoka Graduate School of Pharmaceutical Sciences
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30
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The therapeutic potential of matcha tea: A critical review on human and animal studies. Curr Res Food Sci 2022; 6:100396. [PMID: 36582446 PMCID: PMC9792400 DOI: 10.1016/j.crfs.2022.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/15/2022] [Accepted: 11/17/2022] [Indexed: 11/24/2022] Open
Abstract
Matcha is a powdered form of Japanese green tea that has been gaining global popularity recently. Matcha tea has various health benefits, including an enhancing effect on cognitive function, cardio-metabolic health, and anti-tumorogenesis. To date, randomized clinical trials (RCT) showed that matcha decreases stress, slightly enhances attention and memory, and has no effect on mood. Results regarding the effect of matcha on cognitive function are contradictory and more RCTs are warranted. The cardio-metabolic effects of matcha have only been studied in animals, but findings were more homogenous. Consuming matcha with a high-fat diet resulted in decreased weight gain velocity, food intake, improved serum glucose and lipid profile, reduced inflammatory cytokines and ameliorated oxidative stress. Evidence regarding the anti-tumor function of matcha is very limited. Findings showed that matcha can affect proliferation, viability, antioxidant response, and cell cycle regulation of breast cancer cells. Nonetheless, more studies are needed to examine this effect on different types of cancer cells, and there is also a need to verify it using animal models. Overall, the evidence regarding the effect of matcha tea on cognitive function, cardio-metabolic function, and anti-tumor role is still limited, and conclusions cannot be drawn.
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Relationship between the Grade and the Characteristic Flavor of PCT (Panyong Congou Black Tea). Foods 2022; 11:foods11182815. [PMID: 36140943 PMCID: PMC9497606 DOI: 10.3390/foods11182815] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/17/2022] Open
Abstract
Panyong Congou black tea (PCT) is one of the most representative and historically famous Congou black teas in China and has been gaining more and more attention for its beneficial health properties. Currently, four grades of PCT are available, based on the raw leaf materials and consumer palatability. The chemical profiles distinguishing different grades of PCT are yet to be defined, nor has the relationship with grade been evaluated. In the present study, chemometric analysis showed that epigallocatechin (EGC), catechin (C), polyphenols, gallic acid (GA), and free amino acids are grade related bio-markers of PCT. These compounds are associated with the sweet and mellow aftertaste of PCT. A total of 34 volatile components were identified, of which the three component types with the highest relative percentages were alcohols (51.34–52.51%), ketones (27.31–30.28%), and aldehydes (12.70–13.18%). Additionally, our results revealed that sweet floral and fruity aromas were positively correlated with six volatile organic compounds (VOCs), 1-pentanol, propyl hexanoate, linalool, cyclohexanone, hexanal, and 2,5-dimethylpyrazine. Clear discrimination was achieved using orthogonal projections to latent structures discriminant analysis (OPLS-DA). The findings provide vital information on the characteristic flavor of each grade of PCT.
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Dong X, Gu Y, Rayamajhi S, Thapa A, Meng G, Zhang Q, Liu L, Wu H, Zhang S, Zhang T, Wang X, Li H, Zhang J, Dong J, Zheng X, Cao Z, Sun S, Wang X, Zhou M, Jia Q, Song K, Chang H, Zheng Y, Niu K. Green tea consumption and risk of depressive symptoms: Results from the TCLSIH Cohort Study. J Affect Disord 2022; 310:183-188. [PMID: 35469912 DOI: 10.1016/j.jad.2022.04.112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 04/10/2022] [Accepted: 04/15/2022] [Indexed: 12/01/2022]
Abstract
BACKGROUND The prospective studies on the effect of particular type of tea consumption, especially green tea, on depressive symptoms are limited. OBJECTIVE The aim of this study is to investigate the prospective association between green tea consumption and depressive symptoms in a large general adult population. METHODS This prospective cohort study investigated 7524 participants aged 25 to 90 years from May 2013 to December 2018 and they were free of cardiovascular disease, cancer, and depressive symptoms at baseline. Green tea consumption was obtained through a validated food frequency questionnaire. Depressive symptoms were assessed by using the Self-Rating Depressive Scale (SDS). The association between green tea consumption and depressive symptoms was analyzed by Cox proportional hazards regression models. RESULTS A total of 1064 first incident cases of depressive symptoms (SDS ≥45) occurred during 14,661 person-years of follow-up (median follow-up of 2.0 years). In the crude model, the hazard ratios (95% confidence intervals) were 1.00 (reference), 0.95 (0.81, 1.12), 0.97 (0.83, 1.14) and 0.95 (0.79, 1.14), respectively. After adjusting for demographic characteristics, lifestyle factors, and dietary intake, the multivariable adjusted hazard ratios (95% confidence intervals) were 1.00 (reference), 0.88 (0.74, 1.05), 0.84 (0.69, 1.02) and 0.78 (0.63, 0.97), respectively. CONCLUSIONS The prospective study suggests that frequent green tea consumption is associated with a decreased risk of depressive symptoms in the general Chinese population.
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Affiliation(s)
- Xinrong Dong
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China; Nutrition and Radiation Epidemiology Research Center, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Yeqing Gu
- Nutrition and Radiation Epidemiology Research Center, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Sabina Rayamajhi
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Amrish Thapa
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Ge Meng
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Qing Zhang
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Li Liu
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Hongmei Wu
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Shunming Zhang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Tingjing Zhang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Xuena Wang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Huiping Li
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Juanjuan Zhang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Jun Dong
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Xiaoxi Zheng
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Zhixia Cao
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Shaomei Sun
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Xing Wang
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Ming Zhou
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Qiyu Jia
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Kun Song
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Hong Chang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Yunliang Zheng
- Tianjin Institute of Modern Health Technology, Tianjin, China.
| | - Kaijun Niu
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China; Nutrition and Radiation Epidemiology Research Center, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Tianjin Medical University, Tianjin, China; Tianjin Key Laboratory of Environment, Nutrition and Public Health, Tianjin, China; Center for International Collaborative Research on Environment, Nutrition and Public Health, Tianjin, China.
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Haarhuis JE, Kardinaal A, Kortman GAM. Probiotics, prebiotics and postbiotics for better sleep quality: a narrative review. Benef Microbes 2022; 13:169-182. [PMID: 35815493 DOI: 10.3920/bm2021.0122] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
There is a growing prevalence of sleep problems and insomnia worldwide, urging the development of new treatments to tackle this increase. Several studies have suggested that the gut microbiome might influence sleep quality. The gut microbiome affects the host's health via the production of metabolites and compounds with neuroactive and immunomodulatory properties, which include short-chain fatty acids, secondary bile acids and neurotransmitters. Several of these metabolites and compounds are independently known as wakefulness-promoting (serotonin, epinephrine, dopamine, orexin, histamine, acetylcholine, cortisol) or sleep-promoting (gamma-aminobutyric acid, melatonin). The primary aim of this review was to evaluate the potential of pro-, pre- and postbiotic treatments to improve sleep quality. Additionally, we aimed to evaluate whether each of the treatments could ameliorate stress and anxiety, which are known to bidirectionally correlate with sleep problems. Lastly, we provided a mechanistic explanation for our findings. A literature search was conducted using PubMed, Scopus, Web of Science, and Google Scholar to compare all human trials that met our inclusion criteria and were published before November 2021. We furthermore discussed relevant findings from animal experiments to provide a mechanistic insight. While several studies found that sleep latency, sleep length, and cortisol levels improved after pro-, pre- or postbiotic treatment, others did not show any significant improvements for sleep quality, stress, or anxiety. These discrepancies can be explained by between-study variations in study designs, study populations, treatments, type and level of distress, and sex differences. We conclude that the trials discussed provide some evidence for prebiotics, postbiotics, and traditional probiotics, such as those belonging to lactobacilli and bifidobacteria, to improve sleep quality and stress, but stronger evidence might be found in the future after implementing the methodological adjustments that are suggested in this review.
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Affiliation(s)
- J E Haarhuis
- Division of Human Nutrition and Health, Wageningen University, P.O. Box 17, 6700 AA Wageningen, the Netherlands.,Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, United Kingdom
| | - A Kardinaal
- NIZO food research B.V., Kernhemseweg 2, 6718 ZB Ede, the Netherlands
| | - G A M Kortman
- NIZO food research B.V., Kernhemseweg 2, 6718 ZB Ede, the Netherlands
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Yaegashi A, Kimura T, Hirata T, Tamakoshi A. Green Tea Consumption and Risk of Depression Symptoms: A Systematic Review and Meta-Analysis of Observational Studies. J Nutr Sci Vitaminol (Tokyo) 2022; 68:155-161. [PMID: 35768246 DOI: 10.3177/jnsv.68.155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
This systematic review and meta-analysis aimed to investigate the association between green tea consumption and depression symptom risk, using subgroup analyses concerning study design, geographical region of study, adjustment factors, age, cut-off for the highest consumption category, and depression assessment methods applied. We used PubMed to search for relevant literature. The inclusion criteria were studies that (a) investigated this association as a primary or secondary outcome; (b) published in English; (c) assessed and reported hazard ratios or odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) for depression symptoms, or included sufficient information to allow their calculation; (d) included at least two groups differentiated based on green tea consumption (e.g., high and low); (e) reported the prevalence of depression symptoms in each group; and (f) reported the sample size for each group. Eight articles were found to meet all criteria. The results indicated that high green tea consumption is inversely associated with depression symptoms. The pooled OR was 0.66 (95% CI 0.58-0.74), and significant heterogeneity was not observed. Subgroup analysis showed that study design impacted results (cohort study [one study]: OR=0.29, 95% CI=0.04-2.14; cross-sectional study [seven studies]: OR=0.66, 95% CI=0.59-0.75). These findings suggest that green tea consumption reduces the risk of depression symptoms. This association was also observed in the cohort study included, but the results in which did not reach the significant level. Therefore, further cohort studies are needed to confirm the potential causal relationship in this regard.
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Affiliation(s)
- Akinori Yaegashi
- Graduate School of Medicine, Hokkaido University.,Department of Health and Nutrition, Faculty of Human Science, Hokkaido Bunkyo University
| | | | - Takumi Hirata
- Graduate School of Medicine, Hokkaido University.,Institute for Clinical and Translational Science, Nara Medical University
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Tea (Camellia sinensis): A Review of Nutritional Composition, Potential Applications, and Omics Research. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12125874] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Tea (Camelliasinensis) is the world’s most widely consumed non-alcoholic beverage with essential economic and health benefits since it is an excellent source of polyphenols, catechins, amino acids, flavonoids, carotenoids, vitamins, and polysaccharides. The aim of this review is to summarize the main secondary metabolites in tea plants, and the content and distribution of these compounds in six different types of tea and different organs of tea plant were further investigated. The application of these secondary metabolites on food processing, cosmetics industry, and pharmaceutical industry was reviewed in this study. With the rapid advancements in biotechnology and sequencing technology, omics analyses, including genome, transcriptome, and metabolome, were widely used to detect the main secondary metabolites and their molecular regulatory mechanisms in tea plants. Numerous functional genes and regulatory factors have been discovered, studied, and applied to improve tea plants. Research advances, including secondary metabolites, applications, omics research, and functional gene mining, are comprehensively reviewed here. Further exploration and application trends are briefly described. This review provides a reference for basic and applied research on tea plants.
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Medrano M, Molina-Hidalgo C, Alcantara JMA, Ruiz JR, Jurado-Fasoli L. Acute Effect of a Dietary Multi-Ingredient Nootropic as a Cognitive Enhancer in Young Healthy Adults: A Randomized, Triple-Blinded, Placebo-Controlled, Crossover Trial. Front Nutr 2022; 9:858910. [PMID: 35634417 PMCID: PMC9133906 DOI: 10.3389/fnut.2022.858910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/15/2022] [Indexed: 11/13/2022] Open
Abstract
Aim To study the acute effect of a dietary multi-ingredient nootropic on cognitive performance in young healthy adults. We also analyzed the influence of the dietary multi-ingredient nootropic on emotional state, heart rate (HR), and heart rate variability (HRV). Methods This is a randomized, triple-blinded, placebo-controlled, crossover trial. In total, 26 young healthy adults (50% women; 24.9 ± 3.3 years old) ingested 10 g of a dietary multi-ingredient nootropic [Evo-Gamers®; Harrison Sport Nutrition (HSN), Granada, Spain] or placebo (maltodextrin) in a randomized order (clinicaltrials.gov No. NCT04790188). After 30 min of the ingestion, participants performed a battery of cognitive performance tests to measure the processing speed, inhibitory control, working memory, cognitive flexibility, creativity, and verbal fluency. The emotional status was assessed through questionnaires, and HR and HRV were measured using a heart rate monitor. Results In comparison with placebo, the acute ingestion of the nootropic showed a significantly better response time in several cognitive tests (i.e., processing speed, inhibitory control, spatial working memory, and cognitive flexibility, all P < 0.05 and effect size range of 0.4–0.6). It also displayed a higher accuracy in the processing speed, the inhibitory control, and cognitive flexibility tests (all P < 0.05; effect size ranged from 0.4 to 0.6). Furthermore, the nootropic showed a higher creativity and positive emotions and lower sadness-depression emotions, whereas HR and HRV remained similar between placebo vs. nootropic conditions. However, there were no differences between the nootropic and placebo in verbal fluency, motivation, or anxiety (all P > 0.05). Conclusion An acute ingestion of a dietary multi-ingredient nootropic enhances cognitive performance in comparison with placebo without negatively influencing HR or HRV in young healthy adults.
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Affiliation(s)
- María Medrano
- PROmoting FITness and Health Through Physical Activity Research Group, Department of Physical Education and Sports, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
| | - Cristina Molina-Hidalgo
- PROmoting FITness and Health Through Physical Activity Research Group, Department of Physical Education and Sports, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
- Department of Physiology, Faculty of Medicine, University of Granada, Granada, Spain
| | - Juan M. A. Alcantara
- PROmoting FITness and Health Through Physical Activity Research Group, Department of Physical Education and Sports, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
| | - Jonatan R. Ruiz
- PROmoting FITness and Health Through Physical Activity Research Group, Department of Physical Education and Sports, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
- Instituto de Investigación Biosanitaria, ibs.Granada, Granada, Spain
| | - Lucas Jurado-Fasoli
- PROmoting FITness and Health Through Physical Activity Research Group, Department of Physical Education and Sports, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
- Department of Physiology, Faculty of Medicine, University of Granada, Granada, Spain
- *Correspondence: Lucas Jurado-Fasoli,
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Lange KW, Nakamura Y, Lange KM, Zhao H. Tea and depression. FOOD SCIENCE AND HUMAN WELLNESS 2022. [DOI: 10.1016/j.fshw.2021.12.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Noah L, Morel V, Bertin C, Pouteau E, Macian N, Dualé C, Pereira B, Pickering G. Effect of a Combination of Magnesium, B Vitamins, Rhodiola, and Green Tea (L-Theanine) on Chronically Stressed Healthy Individuals-A Randomized, Placebo-Controlled Study. Nutrients 2022; 14:nu14091863. [PMID: 35565828 PMCID: PMC9102162 DOI: 10.3390/nu14091863] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 02/05/2023] Open
Abstract
The effect of a combination of magnesium, vitamins B6, B9, B12, rhodiola and green tea/L-theanine (Mg-Teadiola) on stress was evaluated in chronically stressed, otherwise healthy individuals. Effects on stress-related quality-of-life parameters (sleep and perception of pain) were also explored. Adults with stress for ≥1 month, scoring ≥14 points on the Depression Anxiety Stress Scale (DASS)-42 questionnaire, were randomized (1:1) to receive oral Mg-Teadiola (n = 49) or a placebo (n = 51), for 28 days, with a follow-up assessment on Day 56 (NCT04391452). The primary endpoint was the change in the DASS-42 stress score from baseline to Day 28 with Mg-Teadiola versus placebo. The DASS-42 stress scores significantly decreased from baseline to Day 28 with Mg-Teadiola versus placebo (effect size, 0.29; 95% CI [0.01, 0.57]; p = 0.04). Similar reductions were observed on Day 14 (p = 0.006) and Day 56 (p = 0.02). A significant reduction in sensitivity to cold pain (p = 0.01) and a trend for lower sensitivity to warm pain was observed (p = 0.06) on Day 28. Improvements in daytime dysfunction due to sleepiness (Pittsburgh Sleep Quality Index-7 component score) were reported on Day 28, and were significant on Day 56 (p < 0.001). Mg-Teadiola is effective in managing stress in otherwise healthy individuals. Its beneficial effects on sleep and pain perception need further investigation.
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Affiliation(s)
- Lionel Noah
- Sanofi, 82, Avenue Raspail, 94250 Gentilly, France; (C.B.); (E.P.)
- Correspondence:
| | - Veronique Morel
- CIC INSERM 1405/Plateforme d’Investigation Clinique CHU Gabriel Montpied, 58 Rue Montalembert, CEDEX 1, 63000 Clermont-Ferrand, France; (V.M.); (N.M.); (C.D.); (B.P.); (G.P.)
| | - Claire Bertin
- Sanofi, 82, Avenue Raspail, 94250 Gentilly, France; (C.B.); (E.P.)
| | - Etienne Pouteau
- Sanofi, 82, Avenue Raspail, 94250 Gentilly, France; (C.B.); (E.P.)
| | - Nicolas Macian
- CIC INSERM 1405/Plateforme d’Investigation Clinique CHU Gabriel Montpied, 58 Rue Montalembert, CEDEX 1, 63000 Clermont-Ferrand, France; (V.M.); (N.M.); (C.D.); (B.P.); (G.P.)
| | - Christian Dualé
- CIC INSERM 1405/Plateforme d’Investigation Clinique CHU Gabriel Montpied, 58 Rue Montalembert, CEDEX 1, 63000 Clermont-Ferrand, France; (V.M.); (N.M.); (C.D.); (B.P.); (G.P.)
| | - Bruno Pereira
- CIC INSERM 1405/Plateforme d’Investigation Clinique CHU Gabriel Montpied, 58 Rue Montalembert, CEDEX 1, 63000 Clermont-Ferrand, France; (V.M.); (N.M.); (C.D.); (B.P.); (G.P.)
| | - Gisèle Pickering
- CIC INSERM 1405/Plateforme d’Investigation Clinique CHU Gabriel Montpied, 58 Rue Montalembert, CEDEX 1, 63000 Clermont-Ferrand, France; (V.M.); (N.M.); (C.D.); (B.P.); (G.P.)
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Optimizing the Quality and Commercial Value of Gyokuro-Styled Green Tea Grown in Australia. BEVERAGES 2022. [DOI: 10.3390/beverages8020022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Gyokuro is a style of Japanese green tea produced by employing agricultural shading in the weeks before harvest. This method results in a tea product with different organoleptic and chemical properties than common Japanese green tea. In an effort to yield the highest quality and commercially valuable green tea product, the present study explores the influence of shading treatments and the duration of shading on the natural biochemistry of the green tea plant. This study applied shading treatments at light intensity conditions of 40%, 16%, 10% and 1% of available ambient light and the application of a red-colored shade cloth of 60% opacity. The Quality Index Tool was used to measure the quality and commercial value of the green tea, using individual target constituents (theanine, caffeine and the catechins) quantified from HPLC analysis. This study shows that very high levels of total visible spectrum light shading (~99%) is required to achieve improvements in quality and commercial value. Specifically, this improvement is a direct result of changes in the mood- modifying bioactive metabolites theanine and caffeine. This study concludes that in green tea growing regions with more hours of sunlight per year, such as on the Central Coast of Australia, more intense shading will achieve products with improved quality and commercial value, which has more potential to be marketed as a functional ingredient.
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Zhu Y, He X, Huang R, Wang W, Yu Y, Zhou T. Screening Bacillus subtilis for Effective L-theanine Production from Tea Plant Rhizosphere Soil. APPL BIOCHEM MICRO+ 2022. [DOI: 10.1134/s000368382202017x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Uyanga VA, Oke EO, Amevor FK, Zhao J, Wang X, Jiao H, Onagbesan OM, Lin H. Functional roles of taurine, L-theanine, L-citrulline, and betaine during heat stress in poultry. J Anim Sci Biotechnol 2022; 13:23. [PMID: 35264238 PMCID: PMC8908636 DOI: 10.1186/s40104-022-00675-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 01/05/2022] [Indexed: 02/11/2023] Open
Abstract
Heat stress (HS) is an important environmental stress factor affecting poultry production on a global scale. With the rise in ambient temperature and increasing effects of global warming, it becomes pertinent to understand the effects of HS on poultry production and the strategies that can be adopted to mitigate its detrimental impacts on the performance, health, welfare, immunity, and survival of birds. Amino acids (AAs) have been increasingly adopted as nutritional modifiers in animals to ameliorate the adverse effects of HS. They are essential for protein synthesis, growth, maintenance, reproduction, immunity, stress response, and whole-body homeostasis. However, HS tends to adversely affect the availability, transport, absorption, and utilization of these AAs. Studies have investigated the provision of these AAs to poultry during HS conditions, and variable findings have been reported. Taurine, L-theanine, and L-citrulline are non-essential amino acids that are increasingly gaining attention as nutritional supplements in HS animals. Similarly, betaine is an amino acid derivative that possesses favorable biological properties which contributes to its role as a functional additive during HS. Of particular note, taurine is negligible in plants, while betaine, L-theanine, and L-citrulline can be found in selected plants. These nutrients are barely found in feed ingredients, but their supply has been shown to elicit important physiological roles including anti-stress effects, anti-oxidative, anti-inflammatory, gut promoting, and immunomodulatory functions. The present review provides information on the use of these nutritionally and physiologically beneficial nutrients as functional additives to poultry diets during HS conditions. Presently, although several studies have reported on the positive effects of these additives in human and murine studies, however, there is limited information regarding their utilization during heat stress in poultry nutrition. Therefore, this review aims to expound on the functional properties of these nutrients, their potentials for HS alleviation, and to stimulate further researches on their biological roles in poultry nutrition.
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Affiliation(s)
- Victoria Anthony Uyanga
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, No. 61 Daizong Street, Tai'an, 271018, Shandong Province, China
| | - Emmanuel O Oke
- Department of Animal Physiology, Federal University of Agriculture, P.M.B, Abeokuta, Ogun State, 2240, Nigeria
| | - Felix Kwame Amevor
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Jingpeng Zhao
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, No. 61 Daizong Street, Tai'an, 271018, Shandong Province, China
| | - Xiaojuan Wang
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, No. 61 Daizong Street, Tai'an, 271018, Shandong Province, China
| | - Hongchao Jiao
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, No. 61 Daizong Street, Tai'an, 271018, Shandong Province, China
| | - Okanlawon M Onagbesan
- Department of Animal Physiology, Federal University of Agriculture, P.M.B, Abeokuta, Ogun State, 2240, Nigeria
| | - Hai Lin
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, No. 61 Daizong Street, Tai'an, 271018, Shandong Province, China.
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Liu K, Liu E, Lin L, Hu Y, Yuan Y, Xiao W. L-Theanine mediates the p38MAPK signaling pathway to alleviate heat-induced oxidative stress and inflammation in mice. Food Funct 2022; 13:2120-2130. [PMID: 35112126 DOI: 10.1039/d1fo03077a] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2025]
Abstract
L-Theanine, an active ingredient in the tea plant (Camellia sinensis) associated with calming, is widely used as a functional ingredient and dietary supplement. In this study, a heat stress mouse model was used to evaluate the anti-heat stress effect of L-theanine and its possible mechanism of action. Mice subjected to heat stress (40 °C) that were administered L-theanine at various doses (100, 200, and 400 mg kg-1 d-1) had reduced oxidative stress and inflammatory factors when L-theanine was administered both long-term and as a preventative treatment. Our L-theanine intervention countered the reduction in growth and feed intake of mice under heat stress and reversed liver and jejunum tissue damage. Moreover, L-theanine countered the increase in inflammatory factors TNF-α, IL-6, and IL-1β and antioxidant enzymes SOD and CAT; it also counteracted GSH-Px inactivation, the upregulation of AST and ALT enzyme activity, and MDA production. The mechanism of action may involve mediation of the P38 signaling pathway, inhibition of MK2 overexpression, and downregulation of p-P65/P65 caused by the overexpression of downstream HSP27. This would inhibit the heat stress-induced imbalance in oxidative stress and inflammatory responses.
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Affiliation(s)
- Kehong Liu
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha 410128, China.
- Key Lab of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Enshuo Liu
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha 410128, China.
- Key Lab of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Ling Lin
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha 410128, China.
- Key Lab of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Yuan Hu
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha 410128, China.
- Key Lab of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Yong Yuan
- Hunan Tea Group Co., Ltd, Changsha 410128, China
| | - Wenjun Xiao
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha 410128, China.
- Key Lab of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan 410128, China
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Thiagarajah K, Chee HP, Sit NW. Effect of Alpha-S1-Casein Tryptic Hydrolysate and L-Theanine on Poor Sleep Quality: A Double Blind, Randomized Placebo-Controlled Crossover Trial. Nutrients 2022; 14:nu14030652. [PMID: 35277011 PMCID: PMC8838692 DOI: 10.3390/nu14030652] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/28/2022] [Accepted: 01/29/2022] [Indexed: 02/04/2023] Open
Abstract
This randomized, placebo-controlled, crossover and double-blind study investigates the effects of RLX2™ containing alpha-s1-casein tryptic hydrolysate and L-theanine in working adults affected by poor sleep quality. The supplement or placebo was randomly and blindly assigned to 39 subjects for four weeks and the changes in the subjective sleep assessment via the Pittsburgh Sleep Quality Index (PSQI), heart rate, blood pressure, salivary cortisol by high-performance liquid chromatography method and alpha power of awake electroencephalogram (EEG) were studied. The data were analyzed in two ways, by crossover and crossover summed up. The latter depicted that RLX2™ improved PSQI total score, sleep latency, sleep duration, sleep habitual efficiency, daytime dysfunction, and increased total and frontal alpha power significantly (p < 0.05). The supplement prolonged the total sleeping time by 45 min in the supplement receiving group compared to the placebo group (p < 0.001). However, only sleep duration and sleep habitual efficiency showed a profound effect in both analyses (p < 0.05). In conclusion, being given its beneficial effects without notable adverse events, it would be advantageous to use these nutraceutical ingredients to promote better sleep quality. Further studies with a larger number participants are warranted to support these findings.
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Chen Y, Liu S, Ferreira JFDS, Xiao L, Gu M, Luo Y, Zhang T, Zhang X, Liu Z, Huang J, Tian N. Development and Application of a Fast Gas Chromatographic Method Offer New Insights into l-theanine Production Regulation in Camellia sinensis L. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:11142-11150. [PMID: 34514782 DOI: 10.1021/acs.jafc.1c04093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Tea is the most consumed beverage worldwide, and l-theanine in tea leaves significantly affects their flavor and market quality. We have developed and validated a fast and reliable gas chromatographic method with flame ionization detection (GC-FID) to quantify l-theanine after its extraction from Camellia sinensis (tea plant) and derivatization. The procedure was completed in 40 min, from extraction to chromatographic analysis, with a recovery rate of more than 93% and allowing a high sample throughput. The GC-FID intraday precision was within 0.57-2.28%, while the interday precision ranged from 1.57 to 13.48%. The intraday accuracy ranged from -6.84 to 5.26%, while the interday accuracy ranged from -1.08 to 3.12%. The limit of detection was 2.28 μg/mL, and the limit of quantification was 6.47 μg/mL. The GC-FID method was validated by high-performance liquid chromatography with UV detection (HPLC-UV) and was used to investigate the biosynthesis and regulation of l-theanine in tea plants. We found that plants fed with ethylamine significantly increased l-theanine concentrations in roots, while exogenous supplementation of glutamic acid, carbamide, and glutamine did not significantly affect the l-theanine level in roots. Our results also indicated that roots were not indispensable for the biosynthesis of l-theanine, which was detected in undifferentiated embryonic calluses in concentrations (g/100 g dry weight) as high as in leaves of whole plants (1.67 and 1.57%, respectively) and without any exogenous theanine precursor supplementation.
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Affiliation(s)
- Yanni Chen
- Department of Tea Science, College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Shuoqian Liu
- Department of Tea Science, College of Horticulture, Hunan Agricultural University, Changsha 410128, China
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha 410128, China
| | - Jorge Freire da Silva Ferreira
- United States Salinity Laboratory, United States Department of Agriculture-Agricultural Research Service, Riverside, California 92507, United States
| | - Lizheng Xiao
- Department of Tea Science, College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Meiyi Gu
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha 410128, China
| | - Yiping Luo
- Department of Tea Science, College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Tiantian Zhang
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha 410128, China
| | - Xiangqin Zhang
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha 410128, China
| | - Zhonghua Liu
- Department of Tea Science, College of Horticulture, Hunan Agricultural University, Changsha 410128, China
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha 410128, China
| | - Jianan Huang
- Department of Tea Science, College of Horticulture, Hunan Agricultural University, Changsha 410128, China
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha 410128, China
| | - Na Tian
- Department of Tea Science, College of Horticulture, Hunan Agricultural University, Changsha 410128, China
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Unno K, Nakamura Y. Green Tea Suppresses Brain Aging. Molecules 2021; 26:molecules26164897. [PMID: 34443485 PMCID: PMC8401650 DOI: 10.3390/molecules26164897] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/06/2021] [Accepted: 08/10/2021] [Indexed: 12/20/2022] Open
Abstract
Epidemiological studies have demonstrated that the intake of green tea is effective in reducing the risk of dementia. The most important component of green tea is epigallocatechin gallate (EGCG). Both EGCG and epigallocatechin (EGC) have been suggested to cross the blood–brain barrier to reach the brain parenchyma, but EGCG has been found to be more effective than EGC in promoting neuronal differentiation. It has also been suggested that the products of EGCG decomposition by the intestinal microbiota promote the differentiation of nerve cells and that both EGCG and its degradation products act on nerve cells with a time lag. On the other hand, the free amino acids theanine and arginine contained in green tea have stress-reducing effects. While long-term stress accelerates the aging of the brain, theanine and arginine suppress the aging of the brain due to their anti-stress effect. Since this effect is counteracted by EGCG and caffeine, the ratios between these green tea components are important for the anti-stress action. In this review, we describe how green tea suppresses brain aging, through the activation of nerve cells by both EGCG and its degradation products, and the reductions in stress achieved by theanine and arginine.
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Askari K, Oryan S, Eidi A, Zaringhalam J, Haghparast A. Modulatory role of the orexin system in stress-induced analgesia: Involvement of the ventral tegmental area. Eur J Pain 2021; 25:2266-2277. [PMID: 34288265 DOI: 10.1002/ejp.1840] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/17/2021] [Indexed: 11/06/2022]
Abstract
BACKGROUND Exposure to stressful experiences is often accompanied by suppressing pain perception, referred to as stress-induced analgesia. The neuropeptides orexins are essential in regulating the mechanism that responds to stressful and painful stimuli. Meanwhile, the ventral tegmental area (VTA), as a part of descending pain inhibitory system, responds to noxious stimuli. This study aimed to investigate the role of intra-VTA administration of orexin receptor antagonists on stress-induced antinociceptive responses in the animal model of acute pain. METHOD Ninety-three adult Wistar rats weighing 230-250 g were unilaterally implanted by a cannulae above the VTA. Animals were pretreated with different doses (1, 3, 10 and 30 nM/0.3 μl) of SB334867 as the orexin-1 receptor antagonist and TCS OX2 29 as the orexin-2 receptor antagonist into the VTA, just 5 min before 6 min exposure to forced swim stress (FSS). Nociceptive threshold was measured using the tail-flick test as a model of acute pain. RESULTS The results showed that exposure to FSS could significantly increase analgesic responses. Moreover, intra-VTA administration of SB334768 and TCS OX2 29 blocked the antinociceptive effect of FSS in the tail-flick test. CONCLUSION The findings suggest that OX1 and OX2 receptors in the VTA might modulate the antinociceptive behaviours induced by FSS in part. SIGNIFICANCE Acute exposure to physical stress suppresses pain-related behaviors in the animal model of acute pain. Blockade of the OX1 and OX2 receptors in the VTA attenuates antinociceptive responses induced by FSS. The contribution of the OX2 receptors in the VTA is more predominant than OX1 receptors in stress-induced analgesia.
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Affiliation(s)
- Kobra Askari
- Department of Animal Biology, Faculty of Biological Science, Kharazmi University, Tehran, Iran
| | - Shahrbanoo Oryan
- Department of Animal Biology, Faculty of Biological Science, Kharazmi University, Tehran, Iran
| | - Akram Eidi
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Jalal Zaringhalam
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Effects of Daily Matcha and Caffeine Intake on Mild Acute Psychological Stress-Related Cognitive Function in Middle-Aged and Older Adults: A Randomized Placebo-Controlled Study. Nutrients 2021; 13:nu13051700. [PMID: 34067795 PMCID: PMC8156288 DOI: 10.3390/nu13051700] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 01/26/2023] Open
Abstract
Matcha, a type of green tea, has a higher amino acid content than other types of tea. We previously examined the ability of matcha to improve cognitive function in older adults and determined that continuous matcha intake improves attention and executive function. This study aimed to compare the effects of matcha and caffeine and clarify the differences between these effects. The study was registered at the University Hospital Medical Information Network (UMIN000036578). The effect of single and continuous intake was compared, and the usefulness of continuous intake was evaluated under the stress condition. The Uchida-Kraepelin test (UKT) was used to induce mild acute stress, and the Cognitrax was used to evaluate cognitive function. A single dose of caffeine improved attentional function during or after stress loading. The reduced reaction time in the Cognitrax, observed following a single dose of matcha, was likely due to caffeine. The matcha group showed an increase in the amount of work after continuous intake, whereas the caffeine group only showed an increase in the amount of work for the UKT after a single dose. Ingesting matcha with caffeine improves both attention and work performance when suffering from psychological stress compared with caffeine alone.
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Production of l-Theanine by Escherichia coli in the Absence of Supplemental Ethylamine. Appl Environ Microbiol 2021; 87:AEM.00031-21. [PMID: 33741612 DOI: 10.1128/aem.00031-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 03/09/2021] [Indexed: 11/20/2022] Open
Abstract
l-Theanine is a nonproteinogenic amino acid present almost exclusively in tea plants and is beneficial for human health. For industrial production, l-theanine is enzymatically or chemically synthesized from glutamine/glutamate (or a glutamine/glutamate derivative) and ethylamine. Ethylamine is extremely flammable and toxic, which complicates and increases the cost of operational procedures. To solve these problems, we developed an artificial biosynthetic pathway to produce l-theanine in the absence of supplemental ethylamine. For this purpose, we identified and selected a novel transaminase (NCBI:protein accession number AAN70747) from Pseudomonas putida KT2440, which catalyzes the transamination of acetaldehyde to produce ethylamine, as well as γ-glutamylmethylamide synthetase (NCBI:protein accession number AAY37316) from Pseudomonas syringae pv. syringae B728a, which catalyzes the condensation of l-glutamate and ethylamine to produce l-theanine. Expressing these genes in Escherichia coli W3110S3GK and enhancing the production capacity of acetaldehyde and l-alanine achieved successful production of l-theanine without ethylamine supplementation. Furthermore, the deletion of ggt, which encodes γ-glutamyltranspeptidase (EC 2.3.2.2), achieved large-scale production of l-theanine by attenuating its decomposition. We show that an alanine decarboxylase-utilizing pathway represents a promising route for the fermentative production of l-theanine. Our study reports efficient methods to produce l-theanine in the absence of supplemental ethylamine.IMPORTANCE l-Theanine is widely used in food additives and dietary supplements. Industrial production of l-theanine uses the toxic and highly flammable precursor ethylamine, raising production costs. In this study, we used Escherichia coli to engineer two biosynthetic pathways that produce l-theanine from glucose and ammonia in the absence of supplemental ethylamine. This study establishes a foundation for safely and economically producing l-theanine.
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Boyle NB, Billington J, Lawton C, Quadt F, Dye L. A combination of green tea, rhodiola, magnesium and B vitamins modulates brain activity and protects against the effects of induced social stress in healthy volunteers. Nutr Neurosci 2021; 25:1845-1859. [PMID: 33896388 DOI: 10.1080/1028415x.2021.1909204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Magnesium (Mg), green tea and rhodiola extracts have, in isolation, been shown to possess stress and anxiety relieving effects. Green tea and rhodiola have been shown to modulate EEG oscillatory brain activity associated with relaxation and stress perception. The combined capacity of these ingredients to confer protective effects under conditions of acute stress has yet to be examined. We tested the hypothesis that a combination of Mg (with B vitamins) + green tea + rhodiola would acutely moderate the effects of stress exposure. METHODS A double blind, randomised, placebo controlled, parallel group design was employed (Clinicaltrials.gov:NCT03262376; 25/0817). One hundred moderately stressed adults received oral supplementation of either (i) Mg + B vitamins + green tea + rhodiola; (ii) Mg + B vitamins + rhodiola; (iii) Mg + B vitamins + green tea; or (iv) placebo. After supplementation participants were exposed to the Trier Social Stress Test. The effects of the study treatments on electroencephalogram (EEG) resting state alpha and theta, subjective state/mood, blood pressure, heart rate variability and salivary cortisol responses after acute stress exposure were assessed. RESULTS The combined treatment significantly increased EEG resting state theta (p < .02) - considered indicative of a relaxed, alert state, attenuated subjective stress, anxiety and mood disturbance, and heightened subjective and autonomic arousal (p < .05). CONCLUSIONS Mg, B vitamins, rhodiola and green tea extracts are a promising combination of ingredients that may enhance coping capacity and offer protection from the negative effects of stress exposure.Trial registration: ClinicalTrials.gov identifier: NCT03262376.
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Affiliation(s)
| | | | - Clare Lawton
- School of Psychology, University of Leeds, Leeds, UK
| | | | - Louise Dye
- School of Psychology, University of Leeds, Leeds, UK
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