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Yan L, Li H, Qian Y, Zhang J, Cong S, Zhang X, Wu L, Wang Y, Wang M, Yu T. Transcutaneous vagus nerve stimulation: a new strategy for Alzheimer's disease intervention through the brain-gut-microbiota axis? Front Aging Neurosci 2024; 16:1334887. [PMID: 38476661 PMCID: PMC10927744 DOI: 10.3389/fnagi.2024.1334887] [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: 11/08/2023] [Accepted: 02/15/2024] [Indexed: 03/14/2024] Open
Abstract
Transcutaneous vagus nerve stimulation (tVNS) is an emerging non-invasive technique designed to stimulate branches of the vagus nerve distributed over the body surface. Studies suggest a correlation between the brain-gut-microbiota (BGM) axis and the pathogenesis of Alzheimer's disease (AD). The BGM axis represents a complex bidirectional communication system, with the vagus nerve being a crucial component. Therefore, non-invasive electrical stimulation of the vagus nerve might have the potential to modify-most of the time probably in a non-physiological way-the signal transmission within the BGM axis, potentially influencing the progression or symptoms of AD. This review explores the interaction between percutaneous vagus nerve stimulation and the BGM axis, emphasizing its potential effects on AD. It examines various aspects, such as specific brain regions, gut microbiota composition, maintenance of intestinal environmental homeostasis, inflammatory responses, brain plasticity, and hypothalamic-pituitary-adrenal (HPA) axis regulation. The review suggests that tVNS could serve as an effective strategy to modulate the BGM axis and potentially intervene in the progression or treatment of Alzheimer's disease in the future.
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Affiliation(s)
- Long Yan
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
- Graduate Department, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Hong Li
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
- Graduate Department, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yulin Qian
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
| | - Junfeng Zhang
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
- Graduate Department, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Shan Cong
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
- Graduate Department, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Xuemin Zhang
- Graduate Department, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Linna Wu
- Graduate Department, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yu Wang
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
| | - Meng Wang
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
| | - Tao Yu
- The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- National Clinical Research Center for Acupuncture and Moxibustion, Tianjin, China
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2
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Lin KY, Yang HY, Yang SC, Chen YL, Watanabe Y, Chen JR. Caulerpa lentillifera improves ethanol-induced liver injury and modulates the gut microbiota in rats. Curr Res Food Sci 2023; 7:100546. [PMID: 37483276 PMCID: PMC10362798 DOI: 10.1016/j.crfs.2023.100546] [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: 05/03/2023] [Revised: 07/02/2023] [Accepted: 07/03/2023] [Indexed: 07/25/2023] Open
Abstract
Caulerpa lentillifera (CL), also called sea grape, is a type of edible green alga which was reported to have antioxidative and immunomodulatory potential. This study aimed to investigate the hepatoprotective effects of CL in a rat model of chronic ethanol exposure. Wistar rats were assigned to four groups and supplied with an isocaloric control liquid diet (group C), an ethanol liquid diet (group E), a control liquid diet supplemented with 5% CL (group CC), or an ethanol liquid diet supplemented with 5% CL (group EC) for a 12-week experimental period. Ethanol feeding induced steatosis, inflammation, and changes in the gut microbiota by the end of the study, whereas CL supplementation significantly improved liver injuries and decreased circulatory endotoxin levels. Moreover, we also found that CL reversed ethanol-induced elevation of hepatic toll-like receptor 4 (TLR4), MyD88 protein expression, the phosphorylated-nuclear factor (NF)-κB-to-NF-κB ratio, and proinflammatory cytokine concentrations. Additionally, CL also increased the abundance of Akkermansia and tight junction proteins and diminished the Firmicutes-to-Bacteroidetes ratio. Dietary CL inhibited the progression of alcoholic liver disease, and some of the possible mechanisms may be strengthening the intestinal barrier function, alleviating dysbiosis, and modulating the TLR4 pathway.
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Affiliation(s)
- Kuan-Yu Lin
- School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan
| | - Hsin-Yi Yang
- Department of Nutritional Science, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Suh-Ching Yang
- School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan
| | - Ya-Ling Chen
- School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan
| | - Y. Watanabe
- General Health Medical Center, Yokohama University of Pharmacy, Yokohama, Japan
| | - Jiun-Rong Chen
- School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan
- Nutrition Research Center, Taipei Medical University Hospital, Taipei, Taiwan
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张 智, 许 丹, 陈 冠, 滕 腾, 伍 虹, 周 新. [Latest Findings on the Interaction Mechanism Between Depressive Disorder and Intestinal Permeability]. SICHUAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF SICHUAN UNIVERSITY. MEDICAL SCIENCE EDITION 2023; 54:257-262. [PMID: 36949682 PMCID: PMC10409181 DOI: 10.12182/20230360503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Indexed: 03/24/2023]
Abstract
The intestinal barrier, a complex structure consisting of multiple layers of defense barriers, blocks the transfer of intestinal and foreign bacteria and their metabolites into the internal environment of the human body. Intestinal permeability can be used to evaluate the integrity of the intestinal barrier. Increased intestinal permeability has been observed in patients with depressive disorder. Some studies have reported an interaction between depressive disorder and intestinal barrier. Herein, we reviewed reported findings on the mechanisms of how systematic low-grade inflammation, vagal nerve dysfunction, and hypothalamic-pituitary-adrenal axis dysfunction cause changes in intestinal permeability in patients with depressive disorder and the pathogenic mechanism of how bacterial translocation caused by damaged intestinal barrier leads to depressive disorder. In addition, the potential mechanisms of how antidepressants improve intestinal permeability and how probiotics improve depressive disorder have been discussed.
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Affiliation(s)
- 智涵 张
- 重庆医科大学附属第一医院 精神科 (重庆 400016)Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - 丹语 许
- 重庆医科大学附属第一医院 精神科 (重庆 400016)Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - 冠源 陈
- 重庆医科大学附属第一医院 精神科 (重庆 400016)Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - 腾 滕
- 重庆医科大学附属第一医院 精神科 (重庆 400016)Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - 虹燕 伍
- 重庆医科大学附属第一医院 精神科 (重庆 400016)Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - 新雨 周
- 重庆医科大学附属第一医院 精神科 (重庆 400016)Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
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Tan C, Yan Q, Ma Y, Fang J, Yang Y. Recognizing the role of the vagus nerve in depression from microbiota-gut brain axis. Front Neurol 2022; 13:1015175. [PMID: 36438957 PMCID: PMC9685564 DOI: 10.3389/fneur.2022.1015175] [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] [Received: 08/09/2022] [Accepted: 09/12/2022] [Indexed: 08/08/2023] Open
Abstract
Depression is a worldwide disease causing severe disability, morbidity, and mortality. Despite abundant studies, the precise mechanisms underlying the pathophysiology of depression remain elusive. Recently, cumulate research suggests that a disturbance of microbiota-gut-brain axis may play a vital role in the etiology of depression while correcting this disturbance could alleviate depression symptoms. The vagus nerve, linking brain and gut through its afferent and efferent branches, is a critical route in the bidirectional communication of this axis. Directly or indirectly, the vagus afferent fibers can sense and relay gut microbiota signals to the brain and induce brain disorders including depression. Also, brain changes in response to stress may result in gut hyperpermeability and inflammation mediating by the vagal efferents, which may be detrimental to depression. Notably, vagus nerve stimulation owns an anti-inflammatory effect and was proved for depression treatment. Nevertheless, depression was accompanied by a low vagal tone, which may derive from response to stress and contribute to pathogenesis of depression. In this review, we aim to explore the role of the vagus nerve in depression from the perspective of the microbiota-gut-brain axis, highlighting the relationship among the vagal tone, the gut hyperpermeability, inflammation, and depression.
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Affiliation(s)
- Chaoren Tan
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Science, Beijing, China
| | - Qiqi Yan
- Institute of Basic Theory for Chinese Medicine, China Academy of Chinese Medical Science, Beijing, China
| | - Yue Ma
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jiliang Fang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yongsheng Yang
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Science, Beijing, China
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Bonaz B. Anti-inflammatory effects of vagal nerve stimulation with a special attention to intestinal barrier dysfunction. Neurogastroenterol Motil 2022; 34:e14456. [PMID: 36097404 PMCID: PMC9787579 DOI: 10.1111/nmo.14456] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 12/30/2022]
Abstract
The vagus nerve (VN), the longest nerve of the organism innervating the gastrointestinal tract, is a mixed nerve with anti-inflammatory properties through its afferents, activating the hypothalamic-pituitary adrenal axis, and its efferents through the cholinergic anti-inflammatory pathway inhibiting the release of pro-inflammatory cytokines (e.g., TNFα) by splenic and gut macrophages. In addition, the VN is also able to modulate the permeability of the intestinal barrier although the VN does not innervate directly the intestinal epithelium. Targeting the VN through VN stimulation (VNS) has been developed in experimental model of intestinal inflammation and in inflammatory bowel disease (IBD) and might be of interest to decrease intestinal permeability in gastrointestinal disorders with intestinal barrier defect such as IBD, irritable bowel syndrome (IBS), and celiac disease. In this issue of neurogastroenterology and motility, Mogilevski et al. report that a brief non-invasive transcutaneous auricular VNS in healthy volunteers consistently reduces the permeability of the small intestine induced by intravenous administration of the stress peptide corticotropin releasing hormone, known to increase intestinal permeability and to inhibit the VN. In this review, we outline the mechanistic underpinning the effect of stress, of the VN and VNS on intestinal permeability. In particular, the VN can act on intestinal permeability through enteric nerves, and/or cells such as enteric glial cells. We also review the existing evidence of the effects VNS on intestinal permeability in models such as burn intestinal injury and traumatic brain injury, which pave the way for future clinical trials in IBD, IBS, and celiac disease.
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Affiliation(s)
- Bruno Bonaz
- Division of Hepato‐GastroenterologyCentre Hospitalier Universitaire Grenoble AlpesGrenobleFrance,Grenoble Institute of Neurosciences, Inserm U1216University Grenoble AlpesGrenobleFrance
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Mogilevski T, Rosella S, Aziz Q, Gibson PR. Transcutaneous vagal nerve stimulation protects against stress-induced intestinal barrier dysfunction in healthy adults. Neurogastroenterol Motil 2022; 34:e14382. [PMID: 35481691 PMCID: PMC9786250 DOI: 10.1111/nmo.14382] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/17/2022] [Accepted: 03/28/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND Intestinal barrier dysfunction is the likely initiating event in multiple human diseases. Currently, there are limited therapeutic strategies to address its dysfunction. Animal studies suggest that vagal nerve stimulation may improve intestinal barrier function, but this has not been evaluated in humans. This study aimed to determine the effect of vagal nerve stimulation on intestinal permeability in adults administered a bolus dose of intravenous corticotropin releasing hormone (CRH) which has been shown to increase small intestinal permeability in healthy human subjects. METHODS In a cross-over study, 16 volunteers (median age 34 years, 11 female) were randomized to receive auricular transcutaneous vagal nerve or sham stimulation (10 minutes each side) after intravenous administration of 100 µg of CRH. Intestinal barrier function was measured before and 2 h after each intervention with dual-sugar urine testing (lactulose:mannitol ratio) and intestinal fatty-acid binding protein (I-FABP). KEY RESULTS Exposure to CRH increased I-FABP concentrations by a median of 49 (IQR 4-71)% (p = 0.009). Lactulose:mannitol ratios were 0.029 (0.025-0.050) following vagal stimulation compared with 0.062 (0.032-0.170) following sham stimulation (p = 0.0092), representing a fall of 53 (22-71)%. I-FABP concentrations did not change (p = 0.90). CONCLUSIONS Brief non-invasive vagal nerve stimulation consistently reduces paracellular permeability of the small intestine after CRH administration, but does not entirely mitigate I-FABP release from the epithelium. Studies of vagal nerve stimulation in disease states are warranted.
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Affiliation(s)
- Tamara Mogilevski
- Department of GastroenterologyMonash University and Alfred HealthMelbourneAustralia,Barts Health NHS trustLondonUK,Centre for NeuroscienceSurgery and TraumaBlizard InstituteWingate Institute of NeurogastroenterologyBarts and the London School of Medicine and DentistryQueen Mary University of LondonLondonUK
| | - Sam Rosella
- Department of GastroenterologyMonash University and Alfred HealthMelbourneAustralia
| | - Qasim Aziz
- Barts Health NHS trustLondonUK,Centre for NeuroscienceSurgery and TraumaBlizard InstituteWingate Institute of NeurogastroenterologyBarts and the London School of Medicine and DentistryQueen Mary University of LondonLondonUK
| | - Peter R. Gibson
- Department of GastroenterologyMonash University and Alfred HealthMelbourneAustralia
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Clark A, Zelmanovich R, Hosseini Siyanaki MR, Michel M, Hanna C, Davidson C, Lucke-Wold B. Microbiome and Neurotrauma: Emerging Innovations. NEUROLOGY & NEUROTHERAPY OPEN ACCESS JOURNAL 2022; 7:170. [PMID: 36035066 PMCID: PMC9410620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The gut-brain axis plays an important role in bidirectional communication that exists and can be altered by injury. Neurotrauma provides acute alteration in the GI tract and alters autonomic function. In this focused review, we highlight what is known about GI disruption following neurotrauma. We then delve into how this affects recovery. Areas of innovation and emerging pre-clinical results are addressed. Finally, we address the link between neurotrauma induced GI dysfunction and progression to neurodegenerative disease states.
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Affiliation(s)
- A Clark
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | - R Zelmanovich
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | | | - M Michel
- Department of Neurosurgery, University of Florida, Gainesville, FL, USA
| | - C Hanna
- Department of Neurosurgery, University of Florida, Gainesville, FL, USA
| | - C Davidson
- Department of Neurosurgery, University of Florida, Gainesville, FL, USA
| | - B Lucke-Wold
- Department of Neurosurgery, University of Florida, Gainesville, FL, USA
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Li H, Page AJ. Altered Vagal Signaling and Its Pathophysiological Roles in Functional Dyspepsia. Front Neurosci 2022; 16:858612. [PMID: 35527812 PMCID: PMC9072791 DOI: 10.3389/fnins.2022.858612] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/28/2022] [Indexed: 11/20/2022] Open
Abstract
The vagus nerve is crucial in the bidirectional communication between the gut and the brain. It is involved in the modulation of a variety of gut and brain functions. Human studies indicate that the descending vagal signaling from the brain is impaired in functional dyspepsia. Growing evidence indicate that the vagal signaling from gut to brain may also be altered, due to the alteration of a variety of gut signals identified in this disorder. The pathophysiological roles of vagal signaling in functional dyspepsia is still largely unknown, although some studies suggested it may contribute to reduced food intake and gastric motility, increased psychological disorders and pain sensation, nausea and vomiting. Understanding the alteration in vagal signaling and its pathophysiological roles in functional dyspepsia may provide information for new potential therapeutic treatments of this disorder. In this review, we summarize and speculate possible alterations in vagal gut-to-brain and brain-to-gut signaling and the potential pathophysiological roles in functional dyspepsia.
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Affiliation(s)
- Hui Li
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
- Nutrition, Diabetes and Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute, Adelaide, SA, Australia
- *Correspondence: Hui Li,
| | - Amanda J. Page
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
- Nutrition, Diabetes and Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute, Adelaide, SA, Australia
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Meroni E, Stakenborg N, Gomez-Pinilla PJ, Stakenborg M, Aguilera-Lizarraga J, Florens M, Delfini M, de Simone V, De Hertogh G, Goverse G, Matteoli G, Boeckxstaens GE. Vagus Nerve Stimulation Promotes Epithelial Proliferation and Controls Colon Monocyte Infiltration During DSS-Induced Colitis. Front Med (Lausanne) 2021; 8:694268. [PMID: 34307422 PMCID: PMC8292675 DOI: 10.3389/fmed.2021.694268] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/07/2021] [Indexed: 12/12/2022] Open
Abstract
Background: We previously showed increased susceptibility to dextran sulfate sodium (DSS)-induced colitis in vagotomized mice. Here, we evaluated whether vagus nerve stimulation (VNS) is able to reduce the severity of DSS colitis and aimed to unravel the mechanism involved. Methods: Colitis was induced in wild type mice by 2.5% DSS administration in drinking water for 5 days. VNS (5 Hz, 1 ms, 1 mA) was applied 1 day prior to and after 4 days of DSS administration to evaluate changes in epithelial integrity and inflammatory response, respectively. Epithelial integrity was assessed using TUNEL and Ki67 staining. Monocytes, immature and mature macrophages were sorted from colonic samples and gene expression levels of pro-inflammatory cytokines were studied. Results: VNS applied prior to DSS administration (i.e., prophylactic VNS) reduced disease activity index (VNS 0.8 ± 0.6 vs. sham 2.8 ± 0.7, p < 0.001, n = 5) and tended to improve histology score. Prophylactic VNS significantly increased epithelial cell proliferation and diminished apoptosis compared to sham stimulation. VNS applied at day 4 during DSS administration (i.e., therapeutic VNS) decreased the influx of monocytes, monocyte-derived macrophages and neutrophils, and significantly reduced pro-inflammatory cytokine expression (i.e., Tnfα and Cxcl1) in immature macrophages compared to sham stimulation. Conclusions: A single period of VNS applied prior to DSS exposure reduced DSS-induced colitis by an improvement in epithelial integrity. On the other hand, VNS applied during the inflammatory phase of DSS colitis reduced cytokine expression in immature macrophages. Our data further underscores the potential of VNS as novel therapeutic approach for inflammatory bowel diseases.
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Affiliation(s)
- Elisa Meroni
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Intestinal Neuro-Immune Interaction, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Nathalie Stakenborg
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Intestinal Neuro-Immune Interaction, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Pedro J Gomez-Pinilla
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Intestinal Neuro-Immune Interaction, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Michelle Stakenborg
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Mucosal Immunology, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Javier Aguilera-Lizarraga
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Intestinal Neuro-Immune Interaction, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Morgane Florens
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Intestinal Neuro-Immune Interaction, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Marcello Delfini
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Intestinal Neuro-Immune Interaction, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Veronica de Simone
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Mucosal Immunology, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Gert De Hertogh
- Department of Pathology, Universitair Ziekenhuis Leuven, Leuven, Belgium
| | - Gera Goverse
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Mucosal Immunology, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Gianluca Matteoli
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Mucosal Immunology, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
| | - Guy E Boeckxstaens
- Translational Research Center for Gastrointestinal Disorders (TARGID), Lab for Intestinal Neuro-Immune Interaction, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven - University of Leuven, Leuven, Belgium
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10
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Williams EC, Coimbra R, Chan TW, Baird A, Eliceiri BP, Costantini TW. Precious cargo: Modulation of the mesenteric lymph exosome payload after hemorrhagic shock. J Trauma Acute Care Surg 2020; 86:52-61. [PMID: 30576304 DOI: 10.1097/ta.0000000000002093] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Trauma/hemorrhagic shock (T/HS) causes a release of proinflammatory mediators into the mesenteric lymph (ML) that may trigger a systemic inflammatory response and subsequent organ failure. Recently, we showed that exosomes in postshock ML are biologically active mediators of this inflammation. Because the specific inflammatory mediators in postshock ML exosomes have yet to be characterized, we hypothesized that T/HS would lead to a distinct ML proinflammatory exosome phenotype that could be identified by proteomic analysis. We further hypothesized that their regulation by the neuroenteric axis via the vagus nerve would modify this proinflammatory profile. METHODS Male rats underwent an established T/HS model including 60 minutes of HS followed by resuscitation. Mesenteric lymph was collected before HS (preshock) and after resuscitation (postshock). A subset of animals underwent cervical vagus nerve electrical stimulation (VNS) after the HS phase. Liquid chromatography with tandem mass spectroscopy (LC-MS/MS) followed by protein identification, label free quantification, and bioinformatic analysis was performed on exosomes from the pre-shock and post-shock phases in the T/HS and T/HS + vagus nerve electrical stimulation groups. Biological activity of exosomes was evaluated using a monocyte nuclear factor kappa B (NF-κB) activity assay. RESULTS ML exosomes express a distinct protein profile after T/HS with enrichment in pathways associated with cell signaling, cell death and survival, and the inflammatory response. Stimulation of the vagus nerve following injury attenuated the transition of ML exosomes to this T/HS-induced inflammatory phenotype with protein expression remaining similar to pre-shock. Monocyte NF-κB activity was increased after exposure to ML exosomes harvested after T/HS, while ML exosomes from preshock had no effect on monocyte NF-κB expression. CONCLUSION Postshock ML exosomes carry a distinct, proinflammatory protein cargo. Stimulating the vagus nerve prevents the T/HS-induced changes in ML exosome protein payload and suggests a novel mechanism by which the neuroenteric axis may limit the systemic inflammatory response after injury.
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Affiliation(s)
- Elliot C Williams
- From the Division of Trauma, Surgical Critical Care, Burns and Acute Care Surgery, Department of Surgery, University of California San Diego Health, San Diego, California (E.C.W., T.W.C., A.B., B.P.E., T.W.C.); and Riverside University Health System Medical Center, Loma Linda University School of Medicine, Moreno Valley, California (R.C.)
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McDonald H, Peart J, Kurniawan ND, Galloway G, Royce SG, Samuel CS, Chen C. Hexarelin targets neuroinflammatory pathways to preserve cardiac morphology and function in a mouse model of myocardial ischemia-reperfusion. Biomed Pharmacother 2020; 127:110165. [PMID: 32403043 DOI: 10.1016/j.biopha.2020.110165] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/15/2020] [Accepted: 04/13/2020] [Indexed: 11/17/2022] Open
Abstract
Acute myocardial ischemia and reperfusion injury (IRI) underly the detrimental effects of coronary heart disease on the myocardium. Despite the ongoing advances in reperfusion therapies, there remains a lack of effective therapeutic strategies for preventing IRI. Growth hormone secretagogues (GHS) have been demonstrated to improve cardiac function, attenuate inflammation and modulate the autonomic nervous system (ANS) in models of cardiovascular disease. Recently, we demonstrated a reduction in infarct size after administration of hexarelin (HEX), in a murine model of myocardial infarction. In the present study we employed a reperfused ischemic (IR) model, to determine whether HEX would continue to have a cardioprotective influence in a model of higher clinical relevance. Myocardial ischemia was induced by transient ligation of the left descending coronary artery (tLAD) in C57BL/6 J mice followed by HEX (0.3 mg/kg/day; n = 20) or vehicle (VEH) (n = 18) administration for 21 days, first administered immediately prior-to reperfusion. IR-injured and sham mice were subjected to high-field magnetic resonance imaging to assess left ventricular (LV) function, with HEX-treated mice demonstrating a significant improvement in LV function compared with VEH-treated mice. A significant decrease in interstitial collagen, TGF-β1 expression and myofibroblast differentiation was also seen in the HEX-treated mice after 21 days. HEX treatment shifted the ANS balance towards a parasympathetic predominance; combined with a significant decrease in cardiac troponin-I and TNF-α levels, these findings were suggestive of an anti-inflammatory action on the myocardium mediated via HEX. In this model of IR, HEX appeared to rebalance the deregulated ANS and activate vagal anti-inflammatory pathways to prevent adverse remodelling and LV dysfunction. There are limited interventions focusing on IRI that have been successful in improving clinical outcome in acute myocardial infarction (AMI) patients, this study provides compelling evidence towards the translational potential of HEX where all others have largely failed.
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Affiliation(s)
- H McDonald
- School of Biomedical Science, University of Queensland, Brisbane, Australia
| | - J Peart
- Menzies Health Institute of Queensland, Griffith University, Gold Coast, Australia
| | - N D Kurniawan
- Centre for Advanced Imaging, University of Queensland, Brisbane, Australia
| | - G Galloway
- Centre for Advanced Imaging, University of Queensland, Brisbane, Australia
| | - S G Royce
- Cardiovascular Disease Program, Biomedical Discovery Institute and Department of Pharmacology, Australia; Central Clinical School, Monash University, Victoria, Australia
| | - C S Samuel
- Cardiovascular Disease Program, Biomedical Discovery Institute and Department of Pharmacology, Australia
| | - C Chen
- School of Biomedical Science, University of Queensland, Brisbane, Australia.
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12
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Abstract
Human and mouse studies have shown that rotavirus infection is associated with low inflammation and unaffected intestinal barrier at the time of diarrhea, properties different from most bacterial and inflammatory diseases of the gut. We showed by in vitro, ex vivo, and in vivo experiments that neurotrophic factors and 5-HT have barrier protective properties during rotavirus insult. These observations advance our understanding of how the gut barrier is protected against rotavirus and suggest that rotavirus affects the gut barrier differently from bacteria. This is the first report to show that neurotrophic factors contribute to maintain the gut epithelial barrier during viral insult. Increased intestinal permeability has been proposed as a mechanism of rotavirus-induced diarrhea. Studies with humans and mice have, however, shown that rotavirus leaves intestinal permeability unaffected or even reduced during diarrhea, in contrast to most bacterial infections. Gastrointestinal permeability is regulated by the vagus nerve and the enteric nervous system, which is composed of neurons and enteric glial cells (EGCs). We investigated whether the vagus nerve, serotonin (5-HT), EGCs, and neurotropic factors contribute to maintaining gut barrier homeostasis during rotavirus infection. Using subdiaphragmatic vagotomized and 5-HT3 receptor knockout mice, we found that the unaffected epithelial barrier during rotavirus infection is independent of the vagus nerve but dependent on 5-HT signaling through enteric intrinsic 5-HT3 receptors. Immunofluorescence analysis showed that rotavirus-infected enterocytes were in close contact with EGCs and enteric neurons and that the glial cell-derived neurotrophic factor (GDNF) was strongly upregulated in enterocytes of infected mice. Moreover, rotavirus and 5-HT activated EGCs (P < 0.001). Using Ussing chambers, we found that GDNF and S-nitrosoglutathione (GSNO) led to denser epithelial barriers in small intestinal resections from noninfected mice (P < 0.01) and humans (P < 0.001) and that permeability was unaffected in rotavirus-infected mice. GSNO made the epithelial barrier denser in Caco-2 cells by increasing the expression of the tight junction protein zona occludens 1 (P < 0.001), resulting in reduced passage of fluorescein isothiocyanate dextran (P < 0.05) in rotavirus-infected monolayers. This is the first report to show that neurotropic factors contribute to maintaining the gut epithelial barrier during viral insult.
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13
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Levine YA, Faltys M, Chernoff D. Harnessing the Inflammatory Reflex for the Treatment of Inflammation-Mediated Diseases. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a034330. [PMID: 30833463 DOI: 10.1101/cshperspect.a034330] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Treating diseases nonpharmacologically, using targeted neurostimulation instead of systemic drugs, is a hallmark of the burgeoning field of bioelectronic medicine. In this review, we provide a brief overview of the discovery and function of the prototypical neuroimmune reflex, the "inflammatory reflex." We discuss various biomarkers developed and used to translate early physiological discoveries into dosing parameters used in experimental settings, from the treatment of animal models of disease through a proof-of-concept clinical study in rheumatoid arthritis (RA). Finally, we relate how unique aspects of this form of therapy enabled the design of a next-generation implanted pulse generator using integrated electrodes, currently under evaluation in a U.S.-based clinical study for patients with drug refractory RA.
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14
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Baritaki S, de Bree E, Chatzaki E, Pothoulakis C. Chronic Stress, Inflammation, and Colon Cancer: A CRH System-Driven Molecular Crosstalk. J Clin Med 2019; 8:E1669. [PMID: 31614860 PMCID: PMC6833069 DOI: 10.3390/jcm8101669] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/08/2019] [Accepted: 10/11/2019] [Indexed: 12/12/2022] Open
Abstract
Chronic stress is thought to be involved in the occurrence and progression of multiple diseases, via mechanisms that still remain largely unknown. Interestingly, key regulators of the stress response, such as members of the corticotropin-releasing-hormone (CRH) family of neuropeptides and receptors, are now known to be implicated in the regulation of chronic inflammation, one of the predisposing factors for oncogenesis and disease progression. However, an interrelationship between stress, inflammation, and malignancy, at least at the molecular level, still remains unclear. Here, we attempt to summarize the current knowledge that supports the inseparable link between chronic stress, inflammation, and colorectal cancer (CRC), by modulation of a cascade of molecular signaling pathways, which are under the regulation of CRH-family members expressed in the brain and periphery. The understanding of the molecular basis of the link among these processes may provide a step forward towards personalized medicine in terms of CRC diagnosis, prognosis and therapeutic targeting.
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Affiliation(s)
- Stavroula Baritaki
- Division of Surgery, School of Medicine, University of Crete, Heraklion, 71500 Crete, Greece.
| | - Eelco de Bree
- Division of Surgery, School of Medicine, University of Crete, Heraklion, 71500 Crete, Greece.
| | - Ekaterini Chatzaki
- Laboratory of Pharmacology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Charalabos Pothoulakis
- IBD Center, Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA 10833, USA.
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15
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Bosmans G, Appeltans I, Stakenborg N, Gomez‐Pinilla PJ, Florens MV, Aguilera‐Lizarraga J, Matteoli G, Boeckxstaens GE. Vagus nerve stimulation dampens intestinal inflammation in a murine model of experimental food allergy. Allergy 2019; 74:1748-1759. [PMID: 30897213 PMCID: PMC6790670 DOI: 10.1111/all.13790] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/29/2019] [Accepted: 02/18/2019] [Indexed: 12/24/2022]
Abstract
Background The vagus nerve has emerged as an important modulator of the intestinal immune system. Its anti‐inflammatory properties have been previously shown in innate and Th1/Th17 predominant inflammatory models. To what extent the vagus nerve is of importance in Th2 inflammatory responses like food allergy is still unclear. In this study, we therefore aimed to investigate the effect of vagotomy (VGX) and vagus nerve stimulation (VNS), on the development and severity of experimental food allergy. Methods Balb/C mice were first sensitized with ovalbumin (OVA) in the presence of alum. Prior to oral challenges with OVA, mice were subjected to VGX or VNS. Disease severity was determined by assessing severity and onset of diarrhoea, OVA‐specific antibody production, mast cell number and activity, inflammatory gene expression in duodenal tissue and lamina propria immune cells by flow cytometry analysis. Results When compared to control mice, VGX did not significantly affect the development and severity of the disease in our model of food allergy. VNS, on the other hand, resulted in a significant amelioration of the different inflammatory parameters assessed. This effect was independent of α7nAChR and is possibly mediated through the dampening of mast cells and increased phagocytosis of OVA by CX3CR1hi macrophages. Conclusions These results underscore the anti‐inflammatory properties of the vagus nerve and the potential of neuro‐immune interactions in the intestine. Further insight into the underlying mechanisms could ultimately lead to novel therapeutic approaches in the treatment of not only food allergy but also other immune‐mediated diseases.
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Affiliation(s)
- Goele Bosmans
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
| | - Iris Appeltans
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
| | - Nathalie Stakenborg
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
| | - Pedro J. Gomez‐Pinilla
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
| | - Morgane V. Florens
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
| | - Javier Aguilera‐Lizarraga
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
| | - Gianluca Matteoli
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
| | - Guy E. Boeckxstaens
- Translational Research Center for Gastrointestinal Disorders (TARGID) Department of Chronic Diseases, Metabolism and Ageing (CHROMETA) KU Leuven Leuven Belgium
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16
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Zubcevic J, Richards EM, Yang T, Kim S, Sumners C, Pepine CJ, Raizada MK. Impaired Autonomic Nervous System-Microbiome Circuit in Hypertension. Circ Res 2019; 125:104-116. [PMID: 31219753 PMCID: PMC6588177 DOI: 10.1161/circresaha.119.313965] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hypertension affects an estimated 103 million Americans, yet gaps in knowledge continue to limit its successful management. Rapidly emerging evidence is linking gut dysbiosis to many disorders and diseases including hypertension. The evolution of the -omics techniques has allowed determination of the abundance and potential function of gut bacterial species by next-generation bacterial sequencing, whereas metabolomics techniques report shifts in bacterial metabolites in the systemic circulation of hypertensive patients and rodent models of hypertension. The gut microbiome and host have evolved to exist in balance and cooperation, and there is extensive crosstalk between the 2 to maintain this balance, including during regulation of blood pressure. However, an understanding of the mechanisms of dysfunctional host-microbiome interactions in hypertension is still lacking. Here, we synthesize some of our recent data with published reports and present concepts and a rationale for our emerging hypothesis of a dysfunctional gut-brain axis in hypertension. Hopefully, this new information will improve the understanding of hypertension and help to address some of these knowledge gaps.
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Affiliation(s)
- Jasenka Zubcevic
- Department of Physiological Sciences, College of Veterinary Medicine; University of Florida, Gainesville FL32610
| | - Elaine M. Richards
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Tao Yang
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Seungbum Kim
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Colin Sumners
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Carl J Pepine
- Division of Cardiovascular Medicine, Department of Medicine, College of Medicine, University of Florida, Gainesville FL32610
| | - Mohan K Raizada
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
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17
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Neural anti-inflammatory action mediated by two types of acetylcholine receptors in the small intestine. Sci Rep 2019; 9:5887. [PMID: 30971711 PMCID: PMC6458176 DOI: 10.1038/s41598-019-41698-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 03/15/2019] [Indexed: 12/14/2022] Open
Abstract
Gastrointestinal prokinetic agents function as serotonin-4 receptor (5-HT4R) agonists to activate myenteric plexus neurons to release acetylcholine (ACh), which then induce anti-inflammatory action. Details of this pathway, however, remain unknown. The aim of this study is to clarify the anti-inflammatory mechanism underlying the 5-HT4R agonist, mosapride citrate (MOS)-induced anti-inflammatory action on postoperative ileus (POI). POI models were generated from wild-type C57BL6/J (WT), 5-HT4R knock-out (S4R KO), α7 nicotinic AChR KO (α7 R KO), and M2 muscarinic ACh receptor KO (M2R KO) mice. MOS attenuated leukocyte infiltration in WT. MOS-induced anti-inflammatory action was completely abolished in both S4R KO and S4R KO mice upon wild-type bone marrow transplantation. MOS-induced anti-inflammatory action against macrophage infiltration, but not neutrophil infiltration, was attenuated in α7 R KO mice. Selective α7nAChR agonists (PNU-282987 and AR-R17779) also inhibited only macrophage infiltration in POI. MOS-mediated inhibition of neutrophil infiltration was diminished by atropine, M2AChR antagonist, methoctramine, and in M2R KO mice. Stimulation with 5-HT4R inhibits leukocyte infiltration in POI, possibly through myenteric plexus activation. Released ACh inhibited macrophage and neutrophil infiltration likely by activation of α7nAChR on macrophages and M2AChR. Thus, macrophage and neutrophil recruitment into inflamed sites is regulated by different types of AChR in the small intestine.
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18
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Uniquely human CHRFAM7A gene increases the hematopoietic stem cell reservoir in mice and amplifies their inflammatory response. Proc Natl Acad Sci U S A 2019; 116:7932-7940. [PMID: 30944217 PMCID: PMC6475388 DOI: 10.1073/pnas.1821853116] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The emergence of uniquely human genes during hominid speciation enabled numerous human-specific adaptations that presumably included changes in resilience to disease but potentially increased susceptibility as well. Here we show that the transgenic expression of one such gene, called CHRFAM7A, changes the mouse reservoir of hematopoietic stem cells in bone marrow and amplifies the mouse inflammatory response in a model of human systemic inflammatory response syndrome (SIRS). Because the CHRFAM7A gene is a dominant-negative inhibitor of ligand binding to α7 nicotinic acetylcholine receptor (α7nAChR), a neurotransmitter receptor implicated in immunity, inflammation, neurodegeneration, and cognitive function, the results underscore the importance of understanding the contribution of species-specific genes to human disease and the impact they may have on the fidelity of animal models for translational medicine. A subset of genes in the human genome are uniquely human and not found in other species. One example is CHRFAM7A, a dominant-negative inhibitor of the antiinflammatory α7 nicotinic acetylcholine receptor (α7nAChR/CHRNA7) that is also a neurotransmitter receptor linked to cognitive function, mental health, and neurodegenerative disease. Here we show that CHRFAM7A blocks ligand binding to both mouse and human α7nAChR, and hypothesized that CHRFAM7A-transgenic mice would allow us to study its biological significance in a tractable animal model of human inflammatory disease, namely SIRS, the systemic inflammatory response syndrome that accompanies severe injury and sepsis. We found that CHRFAM7A increased the hematopoietic stem cell (HSC) reservoir in bone marrow and biased HSC differentiation to the monocyte lineage in vitro. We also observed that while the HSC reservoir was depleted in SIRS, HSCs were spared in CHRFAM7A-transgenic mice and that these mice also had increased immune cell mobilization, myeloid cell differentiation, and a shift to inflammatory monocytes from granulocytes in their inflamed lungs. Together, the findings point to a pathophysiological inflammatory consequence to the emergence of CHRFAM7A in the human genome. To this end, it is interesting to speculate that human genes like CHRFAM7A can account for discrepancies between the effectiveness of drugs like α7nAChR agonists in animal models and human clinical trials for inflammatory and neurodegenerative disease. The findings also support the hypothesis that uniquely human genes may be contributing to underrecognized human-specific differences in resiliency/susceptibility to complications of injury, infection, and inflammation, not to mention the onset of neurodegenerative disease.
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19
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Fornai M, van den Wijngaard RM, Antonioli L, Pellegrini C, Blandizzi C, de Jonge WJ. Neuronal regulation of intestinal immune functions in health and disease. Neurogastroenterol Motil 2018; 30:e13406. [PMID: 30058092 DOI: 10.1111/nmo.13406] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/11/2018] [Indexed: 12/26/2022]
Abstract
BACKGROUND Nerve-mucosa interactions control various elements of gastrointestinal functions, including mucosal host defense, gut barrier function, and epithelial cell growth and differentiation. In both intestinal and extra-intestinal diseases, alterations of autonomic nerve activity have been observed to be concurrent with the disease course, such as in inflammatory and functional bowel diseases, and neurodegenerative diseases. This is relevant as the extrinsic autonomic nervous system is increasingly recognized to modulate gut inflammatory responses. The molecular and cellular mechanisms through which the extrinsic and intrinsic nerve pathways may regulate digestive mucosal functions have been investigated in several pre-clinical and clinical studies. PURPOSE The present review focuses on the involvement of neural pathways in gastrointestinal disease, and addresses the current strategies to intervene with neuronal pathway as a means of treatment.
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Affiliation(s)
- M Fornai
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.,Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands
| | - R M van den Wijngaard
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands
| | - L Antonioli
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - C Pellegrini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - C Blandizzi
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - W J de Jonge
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands
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20
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Guo P, Zhang SW, Zhang J, Dong JT, Wu JD, Tang ST, Yang JT, Zhang WJ, Wu F. Effects of imipenem combined with low-dose cyclophosphamide on the intestinal barrier in septic rats. Exp Ther Med 2018; 16:1919-1927. [PMID: 30186419 PMCID: PMC6122399 DOI: 10.3892/etm.2018.6373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 05/25/2018] [Indexed: 12/29/2022] Open
Abstract
Anti-infection therapy combined with immunotherapy is one of the important research approaches for treating sepsis. However, the combination of anti-infection and immunotherapy therapeutic agents may have an adverse effect on intestinal barrier function. In the present study, it was hypothesized that imipenem combined with low-dose cyclophosphamide (CTX) could improve the sepsis survival rate compared with imipenem treatment alone. In addition, the alterations in the intestinal barrier were investigated and the possible mechanisms of altering intestinal barrier function in septic rats treated with imipenem combined with low-dose CTX or imipenem alone were explored. To investigate the effect of imipenem combined with low-dose CTX on the intestinal barrier, the markers of histopathology, intestinal permeability, intestinal epithelial apoptosis, cytokines interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)-α, and tight junction proteins zonula occludens (ZO)-1, occludin and claudin-2, were quantitatively and qualitatively evaluated. The results indicated that imipenem combined with low-dose CTX significantly improved the survival rate of rats compared with imipenem alone (P<0.05). However, no significantly difference between the treatment with imipenem combined with low-dose CTX and imipenem treatment alone was indicated with regard to histopathology, intestinal permeability, intestinal epithelial apoptosis and the expression of claudin-2, ZO-1 and TNF-α. However, imipenem combined with low-dose CTX significantly reduced IL-6 and IL-10 expression and significantly increased occludin expression compared with imipenem alone (P<0.05). It was concluded that imipenem combined with low-dose CTX could improve the survival rate of rats with sepsis compared with rats treated with imipenem alone. The present findings suggest that imipenem combined with low-dose CTX may cause damage to the intestinal barrier function and the mechanism may be associated with a reduction in IL-10 expression.
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Affiliation(s)
- Peng Guo
- Department of Critical Care Medicine, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang 832000, P.R. China
| | - Shun-Wen Zhang
- First School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu 210000, P.R. China
| | - Jie Zhang
- Department of Emergency, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang 832000, P.R. China
| | - Jiang-Tao Dong
- Department of Neurosurgery, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang 832000, P.R. China
| | - Jiang-Dong Wu
- Department of Pathophysiology, Shihezi University School of Medicine/Key Laboratory of Xinjiang Endemic and Ethnic Diseases/Collaborative Innovation Center of High Incidence of Zoonotic Communicable Disease Prevention in The Western Region, Shihezi, Xinjiang 832000, P.R. China
| | - Su-Tu Tang
- Department of Critical Care Medicine, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang 832000, P.R. China
| | - Jun-Ting Yang
- Department of Pathophysiology, Shihezi University School of Medicine/Key Laboratory of Xinjiang Endemic and Ethnic Diseases/Collaborative Innovation Center of High Incidence of Zoonotic Communicable Disease Prevention in The Western Region, Shihezi, Xinjiang 832000, P.R. China
| | - Wan-Jiang Zhang
- Department of Pathophysiology, Shihezi University School of Medicine/Key Laboratory of Xinjiang Endemic and Ethnic Diseases/Collaborative Innovation Center of High Incidence of Zoonotic Communicable Disease Prevention in The Western Region, Shihezi, Xinjiang 832000, P.R. China
| | - Fang Wu
- Department of Pathophysiology, Shihezi University School of Medicine/Key Laboratory of Xinjiang Endemic and Ethnic Diseases/Collaborative Innovation Center of High Incidence of Zoonotic Communicable Disease Prevention in The Western Region, Shihezi, Xinjiang 832000, P.R. China
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21
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Bonaz B, Bazin T, Pellissier S. The Vagus Nerve at the Interface of the Microbiota-Gut-Brain Axis. Front Neurosci 2018; 12:49. [PMID: 29467611 PMCID: PMC5808284 DOI: 10.3389/fnins.2018.00049] [Citation(s) in RCA: 745] [Impact Index Per Article: 106.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 01/22/2018] [Indexed: 12/13/2022] Open
Abstract
The microbiota, the gut, and the brain communicate through the microbiota-gut-brain axis in a bidirectional way that involves the autonomic nervous system. The vagus nerve (VN), the principal component of the parasympathetic nervous system, is a mixed nerve composed of 80% afferent and 20% efferent fibers. The VN, because of its role in interoceptive awareness, is able to sense the microbiota metabolites through its afferents, to transfer this gut information to the central nervous system where it is integrated in the central autonomic network, and then to generate an adapted or inappropriate response. A cholinergic anti-inflammatory pathway has been described through VN's fibers, which is able to dampen peripheral inflammation and to decrease intestinal permeability, thus very probably modulating microbiota composition. Stress inhibits the VN and has deleterious effects on the gastrointestinal tract and on the microbiota, and is involved in the pathophysiology of gastrointestinal disorders such as irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) which are both characterized by a dysbiosis. A low vagal tone has been described in IBD and IBS patients thus favoring peripheral inflammation. Targeting the VN, for example through VN stimulation which has anti-inflammatory properties, would be of interest to restore homeostasis in the microbiota-gut-brain axis.
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Affiliation(s)
- Bruno Bonaz
- Division of Hepato-Gastroenterology, University Hospital, Grenoble Alpes, France.,Grenoble Institute of Neurosciences, University Grenoble Alpes, Inserm U1216, Grenoble, France
| | - Thomas Bazin
- Institut National de la Recherche Agronomique, Mycoplasmal and Chlamydial Infections in Humans, Univ. Bordeaux, Bordeaux, France.,Department of Hepato-Gastroenterology, Bordeaux Hospital University Center, Pessac, France
| | - Sonia Pellissier
- LIP/PC2S, Université Grenoble Alpes, Université Savoie Mont Blanc, Grenoble, France
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22
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23
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Bosmans G, Shimizu Bassi G, Florens M, Gonzalez-Dominguez E, Matteoli G, Boeckxstaens GE. Cholinergic Modulation of Type 2 Immune Responses. Front Immunol 2017; 8:1873. [PMID: 29312347 PMCID: PMC5742746 DOI: 10.3389/fimmu.2017.01873] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 12/08/2017] [Indexed: 12/28/2022] Open
Abstract
In recent years, the bidirectional relationship between the nervous and immune system has become increasingly clear, and its role in both homeostasis and inflammation has been well documented over the years. Since the introduction of the cholinergic anti-inflammatory pathway, there has been an increased interest in parasympathetic regulation of both innate and adaptive immune responses, including T helper 2 responses. Increasing evidence has been emerging suggesting a role for the parasympathetic nervous system in the pathophysiology of allergic diseases, including allergic rhinitis, asthma, food allergy, and atopic dermatitis. In this review, we will highlight the role of cholinergic modulation by both nicotinic and muscarinic receptors in several key aspects of the allergic inflammatory response, including barrier function, innate and adaptive immune responses, and effector cells responses. A better understanding of these cholinergic processes mediating key aspects of type 2 immune disorders might lead to novel therapeutic approaches to treat allergic diseases.
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Affiliation(s)
- Goele Bosmans
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Gabriel Shimizu Bassi
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Morgane Florens
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Erika Gonzalez-Dominguez
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Gianluca Matteoli
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Guy E Boeckxstaens
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
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Evaluation of gut-blood barrier dysfunction in various models of trauma, hemorrhagic shock, and burn injury. J Trauma Acute Care Surg 2017; 83:944-953. [DOI: 10.1097/ta.0000000000001654] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Sundman MH, Chen NK, Subbian V, Chou YH. The bidirectional gut-brain-microbiota axis as a potential nexus between traumatic brain injury, inflammation, and disease. Brain Behav Immun 2017; 66:31-44. [PMID: 28526435 DOI: 10.1016/j.bbi.2017.05.009] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/25/2017] [Accepted: 05/10/2017] [Indexed: 02/06/2023] Open
Abstract
As head injuries and their sequelae have become an increasingly salient matter of public health, experts in the field have made great progress elucidating the biological processes occurring within the brain at the moment of injury and throughout the recovery thereafter. Given the extraordinary rate at which our collective knowledge of neurotrauma has grown, new insights may be revealed by examining the existing literature across disciplines with a new perspective. This article will aim to expand the scope of this rapidly evolving field of research beyond the confines of the central nervous system (CNS). Specifically, we will examine the extent to which the bidirectional influence of the gut-brain axis modulates the complex biological processes occurring at the time of traumatic brain injury (TBI) and over the days, months, and years that follow. In addition to local enteric signals originating in the gut, it is well accepted that gastrointestinal (GI) physiology is highly regulated by innervation from the CNS. Conversely, emerging data suggests that the function and health of the CNS is modulated by the interaction between 1) neurotransmitters, immune signaling, hormones, and neuropeptides produced in the gut, 2) the composition of the gut microbiota, and 3) integrity of the intestinal wall serving as a barrier to the external environment. Specific to TBI, existing pre-clinical data indicates that head injuries can cause structural and functional damage to the GI tract, but research directly investigating the neuronal consequences of this intestinal damage is lacking. Despite this void, the proposed mechanisms emanating from a damaged gut are closely implicated in the inflammatory processes known to promote neuropathology in the brain following TBI, which suggests the gut-brain axis may be a therapeutic target to reduce the risk of Chronic Traumatic Encephalopathy and other neurodegenerative diseases following TBI. To better appreciate how various peripheral influences are implicated in the health of the CNS following TBI, this paper will also review the secondary biological injury mechanisms and the dynamic pathophysiological response to neurotrauma. Together, this review article will attempt to connect the dots to reveal novel insights into the bidirectional influence of the gut-brain axis and propose a conceptual model relevant to the recovery from TBI and subsequent risk for future neurological conditions.
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Affiliation(s)
- Mark H Sundman
- Department of Psychology, University of Arizona, Tucson, AZ, USA.
| | - Nan-Kuei Chen
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ, USA
| | - Vignesh Subbian
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ, USA; Department of Systems and Industrial Engineering, University of Arizona, Tucson, AZ, USA
| | - Ying-Hui Chou
- Department of Psychology, University of Arizona, Tucson, AZ, USA; Cognitive Science Program, University of Arizona, Tucson, AZ, USA; Arizona Center on Aging, University of Arizona, Tucson, AZ, USA
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26
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Wells R, Tonkin A. Clinical approach to autonomic dysfunction. Intern Med J 2017; 46:1134-1139. [PMID: 27734621 DOI: 10.1111/imj.13216] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/17/2016] [Accepted: 03/24/2016] [Indexed: 12/20/2022]
Abstract
Patients with autonomic dysfunction may present with a variety of seemingly unrelated symptoms, both generalised and involving specific systems, including fatigue, difficulty concentrating, orthostatic intolerance, palpitations, constipation or diarrhoea, early satiety, urinary retention or incontinence and erectile dysfunction. Failure to connect the diverse symptoms with a single underlying mechanism may lead to incorrect diagnoses, inappropriate interventions and frustration on the part of both doctors and patients. We describe recent developments in the understanding of the pathophysiology of autonomic dysfunction, including the link between the autonomic and immune systems resulting in the 'inflammatory reflex'. We then provide a rationale to guide the management of patients exhibiting features of autonomic dysfunction, including postural tachycardia syndrome.
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Affiliation(s)
- R Wells
- Department of Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
| | - A Tonkin
- School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
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Langness S, Kojima M, Coimbra R, Eliceiri BP, Costantini TW. Enteric glia cells are critical to limiting the intestinal inflammatory response after injury. Am J Physiol Gastrointest Liver Physiol 2017; 312:G274-G282. [PMID: 28082286 DOI: 10.1152/ajpgi.00371.2016] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 01/05/2017] [Accepted: 01/05/2017] [Indexed: 02/06/2023]
Abstract
Vagal nerve stimulation (VNS) has been shown to limit intestinal inflammation following injury; however, a direct connection between vagal terminals and resident intestinal immune cells has yet to be identified. We have previously shown that enteric glia cell (EGC) expression is increased after injury through a vagal-mediated pathway to help restore gut barrier function. We hypothesize that EGCs modulate immune cell recruitment following injury and relay vagal anti-inflammatory signals to resident immune cells in the gut. EGCs were selectively ablated from an isolated segment of distal bowel with topical application of benzalkonium chloride (BAC) in male mice. Three days following BAC application, mice were subjected to an ischemia-reperfusion injury (I/R) by superior mesenteric artery occlusion for 30 min. VNS was performed in a separate cohort of animals. EGC+ and EGC- segments were compared utilizing histology, flow cytometry, immunohistochemistry, and intestinal permeability. VNS significantly reduced immune cell recruitment after I/R injury in EGC+ segments with cell percentages similar to sham. VNS failed to limit immune cell recruitment in EGC- segments. Histologic evidence of gut injury was diminished with VNS application in EGC+ segments, whereas EGC- segments showed features of more severe injury. Intestinal permeability increased following I/R injury in both EGC+ and EGC- segments. Permeability was significantly lower after VNS application compared with injury alone in EGC+ segments only (95.1 ± 30.0 vs. 217.6 ± 21.7 μg/ml, P < 0.05). Therefore, EGC ablation uncouples the protective effects of VNS, suggesting that vagal-mediated signals are translated to effector cells through EGCs.NEW & NOTEWORTHY Intestinal inflammation is initiated by local immune cell activation and epithelial barrier breakdown, resulting in the production of proinflammatory mediators with subsequent leukocyte recruitment. Vagal nerve stimulation (VNS) has been shown to limit intestinal inflammation following injury; however, direct connection between vagal terminals and resident intestinal immune cells has yet to be identified. Here, we demonstrate that intact enteric glia cells are required to transmit the gut anti-inflammatory effects of VNS.
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Affiliation(s)
- Simone Langness
- Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Mitsuaki Kojima
- Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Raul Coimbra
- Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Brian P Eliceiri
- Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Todd W Costantini
- Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
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Kwan H, Garzoni L, Liu HL, Cao M, Desrochers A, Fecteau G, Burns P, Frasch MG. Vagus Nerve Stimulation for Treatment of Inflammation: Systematic Review of Animal Models and Clinical Studies. Bioelectron Med 2016. [DOI: 10.15424/bioelectronmed.2016.00005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Kwan H, Garzoni L, Liu HL, Cao M, Desrochers A, Fecteau G, Burns P, Frasch MG. Vagus Nerve Stimulation for Treatment of Inflammation: Systematic Review of Animal Models and Clinical Studies. Bioelectron Med 2016; 3:1-6. [PMID: 29308423 PMCID: PMC5756070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023] Open
Abstract
Vagus nerve stimulation (VNS) has been used since 1997 for treatment of drug-resistant epilepsy. More recently, an off-label use of VNS has been explored in animal models and clinical trials for treatment of a number of conditions involving the innate immune system. The underlying premise has been the notion of the cholinergic antiinflammatory pathway (CAP), mediated by the vagus nerves. While the macroanatomic substrate - the vagus nerve - is understood, the physiology of the pleiotropic VNS effects and the "language" of the vagus nerve, mediated brain-body communication, remain an enigma. Tackling this kind of enigma is precisely the challenge for and promise of bioelectronic medicine. We review the state of the art of this emerging field as it pertains to developing strategies for use of the endogenous CAP to treat inflammation and infection in various animal models and human clinical trials. This is a systematic PubMed review for the MeSH terms "vagus nerve stimulation AND inflammation." We report the diverse profile of currently used VNS antiinflammatory strategies in animal studies and human clinical trials. This review provides a foundation and calls for devising systematic and comparable VNS strategies in animal and human studies for treatment of inflammation. We discuss species-specific differences in the molecular genetics of cholinergic signaling as a framework to understand the divergence in VNS effects between species. Brain-mapping initiatives are needed to decode vagus-carried brain-body communication before hypothesis-driven treatment approaches can be devised.
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Affiliation(s)
- Harwood Kwan
- Department of Obstetrics and Gynecology and Department of Neurosciences, University of Montreal, Montreal, Quebec, Canada
| | - Luca Garzoni
- Department of Pediatrics, CHU Ste-Justine Research Centre, University of Montreal, Montreal, Quebec, Canada
| | - Hai Lun Liu
- Department of Obstetrics and Gynecology and Department of Neurosciences, University of Montreal, Montreal, Quebec, Canada
| | - Mingju Cao
- Department of Obstetrics and Gynecology and Department of Neurosciences, University of Montreal, Montreal, Quebec, Canada
| | - Andre Desrochers
- Department of Clinical Sciences, University of Montreal, St-Hyacinthe, Quebec, Canada
| | - Gilles Fecteau
- Department of Clinical Sciences, University of Montreal, St-Hyacinthe, Quebec, Canada
| | - Patrick Burns
- Department of Clinical Sciences, University of Montreal, St-Hyacinthe, Quebec, Canada
| | - Martin G Frasch
- Department of Obstetrics and Gynecology and Department of Neurosciences, University of Montreal, Montreal, Quebec, Canada
- Centre de Recherche en Reproduction Animale, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Quebec, Canada
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
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Wang L, Zhao B, Chen Y, Ma L, Chen EZ, Mao EQ. Biliary tract external drainage alleviates kidney injury in shock. J Surg Res 2015; 199:564-571. [PMID: 26163328 DOI: 10.1016/j.jss.2015.05.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 05/09/2015] [Accepted: 05/15/2015] [Indexed: 02/02/2023]
Abstract
BACKGROUND Kidney injury is common in hemorrhagic shock (HS). Kidney injury leads to a systemic increase in serum chemokines and cytokines and causes injuries to other vital organs. Our previous studies showed that vitamin C led to organ protection and inflammation inhibitory effects in rat models of HS via induction heme oxygenase-1 (HO-1). We also found that biliary tract external drainage (BTED) increased the expression levels of HO-1 in rat livers. We investigated roles of BTED in kidney injury and its relationship with the HO-1 pathway in HS in this research. METHODS Rat models of HS were induced by drawing blood from the femoral artery. BTED was performed by inserting a catheter into the bile duct. Thirty-six Sprague-Dawley rats were randomized to sham group; HS group; zinc protoporphyrin IX (Znpp) group; BTED group; BTED + Znpp group, and BTED + bile infusion group. The expression levels of HO-1 in the kidney were analyzed by Western blotting. The expression levels of occludin messenger RNA in the kidney were analyzed by real-time reverse transcription-polymerase chain reaction. The expression levels of occludin in the kidney were analyzed by immunohistochemistry. Histology of renal was performed by hematoxylin and eosin staining. RESULTS Occludin messenger RNA and protein levels in the kidney increased markedly after BTED under HS conditions. Renal histopathologic scores decreased significantly after BTED under HS conditions. Znpp significantly inhibited all mentioned effects. CONCLUSIONS BTED alleviates kidney injury in rats of HS via the HO-1 pathway.
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Affiliation(s)
- Lu Wang
- Department of Emergency Intensive Care Unit, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Bing Zhao
- Department of Emergency Intensive Care Unit, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ying Chen
- Department of Emergency Intensive Care Unit, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Li Ma
- Department of Emergency Intensive Care Unit, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Er-Zhen Chen
- Department of Emergency Intensive Care Unit, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - En-Qiang Mao
- Department of Emergency Intensive Care Unit, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Van Houten JM, Wessells RJ, Lujan HL, DiCarlo SE. My gut feeling says rest: Increased intestinal permeability contributes to chronic diseases in high-intensity exercisers. Med Hypotheses 2015; 85:882-6. [PMID: 26415977 DOI: 10.1016/j.mehy.2015.09.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 09/12/2015] [Indexed: 12/28/2022]
Abstract
Chronic diseases are the leading cause of death and disability worldwide, and many of these conditions are linked to chronic inflammation. One potential cause of chronic inflammation is an increased intestinal epithelial permeability. Recent studies have demonstrated that parasympathetic stimulation via the efferent abdominal vagus nerve increases the expression and proper localization of tight junction proteins and decreases intestinal epithelial permeability. This finding may provide a novel approach for treating and preventing many chronic conditions. Importantly, physical activity is associated with increased resting parasympathetic (vagal) activity and lower risk of chronic diseases. However, high intensity long duration exercise can be harmful to overall health. Specifically, individuals who frequently exercise strenuously and for longer time intervals have the same mortality rates as sedentary individuals. This may be explained, in part, by longer periods of reduced vagal activity as vagal activity is markedly reduced both during and after intense exercise. We hypothesize that one mechanism by which exercise provides its health benefits is by increasing resting vagal activity and decreasing intestinal epithelial permeability, thus decreasing chronic inflammation. Additionally, we hypothesize that long periods of reduced vagal activity in individuals who exercise at high intensities and for longer durations, decrease the integrity of the intestinal barrier, putting them at greater risk of chronic inflammation and a host of chronic diseases. Thus, this hypothesis provides a conceptual link between the well-established benefits of frequent exercise and the paradoxical deleterious effects of prolonged, high-intensity exercise without adequate rest.
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Affiliation(s)
- Jason M Van Houten
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201, United States
| | - Robert J Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201, United States
| | - Heidi L Lujan
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201, United States
| | - Stephen E DiCarlo
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201, United States.
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Costantini TW, Dang X, Yurchyshyna MV, Coimbra R, Eliceiri BP, Baird A. A Human-Specific α7-Nicotinic Acetylcholine Receptor Gene in Human Leukocytes: Identification, Regulation and the Consequences of CHRFAM7A Expression. Mol Med 2015; 21:323-36. [PMID: 25860877 DOI: 10.2119/molmed.2015.00018] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 04/02/2015] [Indexed: 12/30/2022] Open
Abstract
The human genome contains a variant form of the α7-nicotinic acetylcholine receptor (α7nAChR) gene that is uniquely human. This CHRFAM7A gene arose during human speciation and recent data suggests that its expression alters ligand tropism of the normally homopentameric human α7-AChR ligand-gated cell surface ion channel that is found on the surface of many different cell types. To understand its possible significance in regulating inflammation in humans, we investigated its expression in normal human leukocytes and leukocyte cell lines, compared CHRFAM7A expression to that of the CHRNA7 gene, mapped its promoter and characterized the effects of stable CHRFAM7A overexpression. We report here that CHRFAM7A is highly expressed in human leukocytes but that the levels of both CHRFAM7A and CHRNA7 mRNAs were independent and varied widely. To this end, mapping of the CHRFAM7A promoter in its 5'-untranslated region (UTR) identified a unique 1-kb sequence that independently regulates CHRFAM7A gene expression. Because overexpression of CHRFAM7A in THP1 cells altered the cell phenotype and modified the expression of genes associated with focal adhesion (for example, FAK, P13K, Akt, rho, GEF, Elk1, CycD), leukocyte transepithelial migration (Nox, ITG, MMPs, PKC) and cancer (kit, kitL, ras, cFos cyclinD1, Frizzled and GPCR), we conclude that CHRFAM7A is biologically active. Most surprisingly however, stable CHRFAM7A overexpression in THP1 cells upregulated CHRNA7, which, in turn, led to increased binding of the specific α7nAChR ligand, bungarotoxin, on the THP1 cell surface. Taken together, these data confirm the close association between CHRFAM7A and CHRNA7 expression, establish a biological consequence to CHRFAM7A expression in human leukocytes and support the possibility that this human-specific gene might contribute to, and/or gauge, a human-specific response to inflammation.
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Affiliation(s)
- Todd W Costantini
- Department of Surgery, University of California San Diego Health Sciences, San Diego, California, United States of America
| | - Xitong Dang
- Department of Surgery, University of California San Diego Health Sciences, San Diego, California, United States of America.,Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
| | - Maryana V Yurchyshyna
- Department of Surgery, University of California San Diego Health Sciences, San Diego, California, United States of America
| | - Raul Coimbra
- Department of Surgery, University of California San Diego Health Sciences, San Diego, California, United States of America
| | - Brian P Eliceiri
- Department of Surgery, University of California San Diego Health Sciences, San Diego, California, United States of America
| | - Andrew Baird
- Department of Surgery, University of California San Diego Health Sciences, San Diego, California, United States of America
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A pharmacologic approach to vagal nerve stimulation prevents mesenteric lymph toxicity after hemorrhagic shock. J Trauma Acute Care Surg 2015; 78:52-8; discussion 58-9. [PMID: 25539203 DOI: 10.1097/ta.0000000000000489] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND Electrical stimulation of the vagus nerve (VN) prevents gut and lung inflammation and mesenteric lymph (ML) toxicity in animal models of injury. We have previously shown that treatment with CPSI-121, a guanylhydrazone-derived compound, prevents gut barrier failure after burn injury. While the structure of CPSI-121 predicts that it will activate parasympathetic signaling, its ability to stimulate the VN is unknown. The aims of this study were to (1) measure the ability of CPSI-121 to induce VN activity, (2) determine whether CPSI-121 causes significant hemodynamic effects, and (3) further define the potential for CPSI-121 to limit the systemic inflammatory response to injury. METHODS Male Sprague-Dawley rats were given 1-mg/kg CPSI-121 intravenously while blood pressure, heart rate, and efferent VN electrical activity were recorded. Rats were also assigned to sham or trauma/hemorrhagic shock (T/HS). T/HS was induced by laparotomy and 60 minutes of HS (mean arterial pressure, 35 mm Hg) followed by fluid resuscitation. A separate cohort of animals received CPSI-121 after the HS phase. Gut and lung tissues were harvested for histologic analysis. Lung wet-dry ratios were also evaluated. The ability of ML to prime neutrophils was assessed by measuring in vitro oxidative burst using flow cytometry. RESULTS Blood pressure was not altered after treatment with CPSI-121, while heart rate decreased only slightly. Recording of efferent VN electrical activity revealed an increase in discharge rate after administration of CPSI-121. T/HS caused gut and lung injury, which were prevented in animals treated with CPSI-121 (p < 0.05). Treatment with CPSI-121 following T/HS attenuated neutrophil priming after exposure to ML (p < 0.05). CONCLUSION CPSI-121 causes efferent VN output and limits shock-induced gut and lung injury as well as ML toxicity. CPSI-121 is a candidate pharmacologic approach to VN stimulation aimed at limiting the inflammatory response in patients following T/HS.
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Dang X, Eliceiri BP, Baird A, Costantini TW. CHRFAM7A: a human-specific α7-nicotinic acetylcholine receptor gene shows differential responsiveness of human intestinal epithelial cells to LPS. FASEB J 2015; 29:2292-302. [PMID: 25681457 DOI: 10.1096/fj.14-268037] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 01/20/2015] [Indexed: 02/06/2023]
Abstract
The human genome contains a unique, distinct, and human-specific α7-nicotinic acetylcholine receptor (α7nAChR) gene [CHRNA7 (gene-encoding α7-nicotinic acetylcholine receptor)] called CHRFAM7A (gene-encoding dup-α7-nicotinic acetylcholine receptor) on a locus of chromosome 15 associated with mental illness, including schizophrenia. Located 5' upstream from the "wild-type" CHRNA7 gene that is found in other vertebrates, we demonstrate CHRFAM7A expression in a broad range of epithelial cells and sequenced the CHRFAM7A transcript found in normal human fetal small intestine epithelial (FHs) cells to prove its identity. We then compared its expression to CHRNA7 in 11 gut epithelial cell lines, showed that there is a differential response to LPS when compared to CHRNA7, and characterized the CHRFAM7A promoter. We report that both CHRFAM7A and CHRNA7 gene expression are widely distributed in human epithelial cell lines but that the levels of CHRFAM7A gene expression vary up to 5000-fold between different gut epithelial cells. A 3-hour treatment of epithelial cells with 100 ng/ml LPS increased CHRFAM7A gene expression by almost 1000-fold but had little effect on CHRNA7 gene expression. Mapping the regulatory elements responsible for CHRFAM7A gene expression identifies a 1 kb sequence in the UTR of the CHRFAM7A gene that is modulated by LPS. Taken together, these data establish the presence, identity, and differential regulation of the human-specific CHRFAM7A gene in human gut epithelial cells. In light of the fact that CHRFAM7A expression is reported to modulate ligand binding to, and alter the activity of, the wild-type α7nAChR ligand-gated pentameric ion channel, the findings point to the existence of a species-specific α7nAChR response that might regulate gut epithelial function in a human-specific fashion.
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Affiliation(s)
- Xitong Dang
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
| | - Brian P Eliceiri
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
| | - Andrew Baird
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
| | - Todd W Costantini
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
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Costantini TW, Dang X, Coimbra R, Eliceiri BP, Baird A. CHRFAM7A, a human-specific and partially duplicated α7-nicotinic acetylcholine receptor gene with the potential to specify a human-specific inflammatory response to injury. J Leukoc Biol 2014; 97:247-57. [PMID: 25473097 DOI: 10.1189/jlb.4ru0814-381r] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Conventional wisdom presumes that the α7nAChR product of CHRNA7 expression mediates the ability of the vagus nerve to regulate the inflammatory response to injury and infection. Yet, 15 years ago, a 2nd structurally distinct and human-specific α7nAChR gene was discovered that has largely escaped attention of the inflammation research community. The gene, originally called dupα7nAChR but now known as CHRFAM7A, has been studied exhaustively in psychiatric research because of its association with mental illness. However, dupα7nAChR/CHRFAM7A expression is relatively low in human brain but elevated in human leukocytes. Furthermore, α7nAChR research in human tissues has been confounded by cross-reacting antibodies and nonspecific oligonucleotide primers that crossreact in immunoblotting, immunohistochemistry, and RT-PCR. Yet, 3 independent reports show the human-specific CHRFAM7A changes cell responsiveness to the canonical α7nAChR/CHRNA7 ion-gated channel. Because of its potential for the injury research community, its possible significance to human leukocyte biology, and its relevance to human inflammation, we review the discovery and structure of the dupα7nAChR/CHRFAM7A gene, the distribution of its mRNA, and its biologic activities and then discuss its possible role(s) in specifying human inflammation and injury. In light of emerging concepts that point to a role for human-specific genes in complex human disease, the existence of a human-specific α7nAChR regulating inflammatory responses in injury underscores the need for caution in extrapolating findings in the α7nAChR literature to man. To this end, we discuss the translational implications of a uniquely human α7nAChR-like gene on new drug target discovery and therapeutics development for injury, infection, and inflammation.
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Affiliation(s)
- Todd W Costantini
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Xitong Dang
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Raul Coimbra
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Brian P Eliceiri
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Andrew Baird
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
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Rezende-Neto JB, Alves RL, Carvalho M, Almeida T, Trant C, Kushmerick C, Andrade M, Rizoli SB, Cunha-Melo J. Vagus nerve stimulation improves coagulopathy in hemorrhagic shock: a thromboelastometric animal model study. J Trauma Manag Outcomes 2014; 8:15. [PMID: 25243020 PMCID: PMC4169132 DOI: 10.1186/1752-2897-8-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 09/12/2014] [Indexed: 11/17/2022]
Abstract
Introduction Inflammation plays a major role in the multifactorial process of trauma associated coagulopathy. The vagus nerve regulates the cholinergic anti-inflammatory pathway. We hypothesized that efferent vagus nerve stimulation (VNS) can improve coagulopathy by modulating the inflammatory response to hemorrhage. Methods Wistar rats (n = 24) were divided in 3 groups: Group (G1) Sham hemorrhagic shock (HS); (G2) HS w/o VNS; (G3) HS followed by division of the vagus nerves and VNS of the distal stumps. Hemorrhage (45% of baseline MAPx15 minutes) was followed by normotensive resuscitation with LR. Vagus nerves were stimulated (3.5 mA, 5 Hz) for 30 sec 7 times. Samples were obtained at baseline and at 60 minutes for thromboelastometry (Rotem®) and cytokine assays (IL-1 and IL-10). ANOVA was used for statistical analysis; significance was set at p < 0.05. Results Maximum clot firmness (MCF) significantly decreased in G2 after HS (71.5 ± 1.5 vs. 64 ± 1.6) (p < 0.05). MCF significantly increased in G3 compared to baseline (67.3 ± 2.7 vs. 71.5 ± 1.2) (p < 0.05). G3 also showed significant improvement in Alfa angle, and Clot Formation Time (CFT) compared to baseline. IL-1 increased significantly in group 2 and decrease in group 3, while IL-10 increased in group 3 (p < 0.05). Conclusions Electrical stimulation of efferent vagus nerves, during resuscitation (G3), decreases inflammatory response to hemorrhage and improves coagulation.
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Affiliation(s)
- Joao B Rezende-Neto
- Department of General Surgery, St. Michael's Hospital - University of Toronto, Toronto, ON, Canada
| | | | - Mario Carvalho
- Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Thiago Almeida
- Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Cyntia Trant
- Federal University of Minas Gerais, Belo Horizonte, Brazil
| | | | - Marcus Andrade
- Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Sandro B Rizoli
- Department of General Surgery, St. Michael's Hospital - University of Toronto, Toronto, ON, Canada
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Lowry DM, Morishita K, Eliceiri BP, Bansal V, Coimbra R, Costantini TW. The vagus nerve alters the pulmonary dendritic cell response to injury. J Surg Res 2014; 192:12-8. [PMID: 25005822 DOI: 10.1016/j.jss.2014.06.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/29/2014] [Accepted: 06/04/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND We have shown previously that vagal nerve stimulation (VNS) protects against burn-induced acute lung injury (ALI). Although the mobilization and activation of immune cells is central to tissue injury caused by the systemic inflammatory response, the specific inflammatory cell populations that are modulated by VNS have yet to be fully defined. The purpose of this study was to assess whether VNS alters inflammatory cell recruitment to the lung after severe burn injury. MATERIALS AND METHODS Male C57BL/6 mice were subjected to 30% total body surface area steam burn with and without electrical stimulation of the right cervical vagus nerve. The relative levels of pulmonary dendritic cells (DC) and macrophages were compared at 4 h versus 24 h after burn injury. Lung tissue injury was characterized by histology to assess changes in lung architecture, and measure the protein levels of interleukin 6 and transforming growth factor-β1. RESULTS Severe burn caused an increase in pulmonary DC recruitment at 4 h after injury that persisted at 24 h after severe burn, whereas there was no change in the number of pulmonary macrophages. In contrast, VNS limited the burn-induced recruitment of pulmonary DC. VNS prevented histologic lung injury and attenuated the release of interleukin 6 and transforming growth factor-β1 in the lung after burn injury. CONCLUSIONS VNS is an effective method to limit pulmonary DC recruitment to the lung and prevent ALI after burn injury. Identifying strategies to limit inflammatory cell recruitment to the lung may have clinical utility in preventing ALI in severely burned patients.
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Affiliation(s)
- Debra M Lowry
- Division of Trauma, Surgical Critical Care, and Burns, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Koji Morishita
- Division of Trauma, Surgical Critical Care, and Burns, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Brian P Eliceiri
- Division of Trauma, Surgical Critical Care, and Burns, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Vishal Bansal
- Division of Trauma, Surgical Critical Care, and Burns, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Raul Coimbra
- Division of Trauma, Surgical Critical Care, and Burns, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California
| | - Todd W Costantini
- Division of Trauma, Surgical Critical Care, and Burns, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California.
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Cheadle GA, Costantini TW, Bansal V, Eliceiri BP, Coimbra R. Cholinergic signaling in the gut: a novel mechanism of barrier protection through activation of enteric glia cells. Surg Infect (Larchmt) 2014; 15:387-93. [PMID: 24828283 DOI: 10.1089/sur.2013.103] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Enteric glia cells (EGCs) play an important role in maintaining proper intestinal barrier function. We have shown that vagal nerve stimulation (VNS) increases EGC activation, which is associated with better gut barrier integrity. Enteric neurons communicate with EGCs through nicotinic cholinergic signaling, which may represent a pathway by which VNS activates EGCs. This study sought to define further the mechanism by which VNS prevents intestinal barrier failure using an in vitro model. We hypothesized that a nicotinic cholinergic agonist would increase EGC activation, prevent intestinal nuclear factor kappa-B (NF-κB) activation, and result in better intestinal barrier function. METHODS Cultured EGCs were exposed to the nicotinic cholinergic agonist nicotine. Expression of glial fibrillary acidic protein (GFAP) was measured by immunoblot to determine changes in EGC activation. Caco-2 cells were grown to confluence and incubated alone or in co-culture with EGCs. Cells were then stimulated with Cytomix for 24 h in the presence or absence of nicotine, and barrier integrity was assessed by permeability to 4-kDa FITC-dextran. Changes in phosphorylated inhibitor of NF-κb (P-IκBα) and phosphorylated NF-κB (P-NF-κB) were assessed by immunoblot. RESULTS Stimulation with nicotine resulted in EGC activation, as demonstrated by an increase in GFAP expression. Cytomix stimulation increased permeability in Caco-2 cells cultured alone or with EGCs. Treatment of stimulated Caco-2/EGC co-cultures with nicotine reduced permeability similar to control. Nicotine failed to prevent barrier permeability in Caco-2 cells alone. Co-culture of stimulated Caco-2 cells with nicotine-activated EGCs prevented Cytomix-induced increases in P-IκBα and P-NF-κB expression. CONCLUSION A pharmacologic nicotinic cholinergic agonist increased EGC activation and improved intestinal epithelial barrier function in an in vitro model of intestinal injury. Nicotine-activated EGCs appear to modulate barrier function by preventing the activation of the NF-κB pathway. Therapies aimed at activating EGCs may have important clinical applications for improving intestinal barrier function after injury.
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Affiliation(s)
- Gerald A Cheadle
- Division of Trauma, Surgical Critical Care, and Burns, Department of Surgery, University of California San Diego Health Sciences , San Diego, California
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Trends in trauma surgery: analysis of the American Association for the Surgery of Trauma program 1939-2012. J Trauma Acute Care Surg 2014; 76:672-80; discussion 680-1. [PMID: 24553533 DOI: 10.1097/ta.0000000000000149] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Major trauma-related clinical and basic science innovations have been presented at American Association for the Surgery of Trauma (AAST) annual meetings since its establishment in 1938. Thus, an analysis of all podium presentations was performed to identify historical and current trends in trauma surgery. METHODS All abstract books of the annual meetings of the AAST from 1939 (first meeting) to 2012 were identified except for 1943 and 1945 (no meeting because of World War II) and 1946 (not found). A master list of abstracts (n = 3,637) was generated in Excel. Abstracts were assigned to 14 different categories, and the percentage of each category was tabulated per year. Trend lines were then generated using a mean of 10 zones. In addition, the year in which major clinical and basic science advancements were first presented was recorded. RESULTS Overall, most (20%) AAST presentations have been related to the resuscitation, shock, infection, inflammation, immunology, endocrinology, and metabolism category. This has been followed by the orthopedic (18%) and the torso (chest and abdomen) trauma categories (15%). The trend for each category over time was identified. Prominent trends included a bell-shaped curve for torso, vascular, and genitourinary injuries; a progressive decrease in orthopedic topics; and an increase in critical care topics since the 1970s and in resuscitation/infection/shock and trauma system presentations since the 1980s. First presentations of key topics were identified (n = 163) and tabulated in a chronological order. CONCLUSION Analysis of all oral AAST presentations identified trends and significant milestones in trauma care and research. In its 75 years of existence, the AAST annual meeting remains the forum in which major developments in trauma care and scientific knowledge are presented and disseminated.
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Vagal nerve stimulation modulates the dendritic cell profile in posthemorrhagic shock mesenteric lymph. J Trauma Acute Care Surg 2014; 76:610-7; discussion 617-8. [PMID: 24553526 DOI: 10.1097/ta.0000000000000137] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Previous studies have established that posthemorrhagic shock mesenteric lymph (PHSML) contains proinflammatory mediators, while the cellular basis of PHSML is less well characterized in acute models of injury. CD103 dendritic cells (DCs) have been identified in the mesenteric lymph (ML) in models of chronic intestinal inflammation, suggesting an important role in the gut response to injury. We have previously demonstrated the ability of vagal nerve stimulation (VNS) to prevent gut barrier failure after trauma/hemorrhagic shock (T/HS); however, the ability of VNS to alter ML DCs is unknown. We hypothesized that the CD103 MHC-II DC population would change in PHSML and that VNS would prevent injury-induced changes in this population in PHSML. METHODS Male Sprague-Dawley rats were randomly assigned to trauma/sham shock or T/HS. T/HS was induced by midline laparotomy and 60 minutes of HS (blood pressure, 35 mm Hg), followed by fluid resuscitation. A separate cohort of animals underwent cervical VNS after the HS phase. Gut tissue was harvested at 2 hours after injury for histologic analysis. ML was collected during the pre-HS, HS, and post-HS phase. For flow cytometric analysis, ML cells were subjected to staining with CD103 and MHC-II antibodies, and this cell population was compared in the pre-HS and post-HS phase from the same animal. The CD4Foxp3 cell (T reg) population in the ML node (MLN) was also tested to determine effects of CD103 DC modulation in the ML. RESULTS VNS reduced histologic gut injury and ML flow seen after injury. The CD103 MHC-II DC population in the PHSML was significantly decreased compared with pre-HS and was associated with decreased T reg expression in the MLN. VNS prevented the injury-induced decrease in the CD103 MHC-II+ DC population in the ML and restored the T reg population in the MLN. CONCLUSION These findings suggest that VNS mediates the inflammatory responses in ML DCs and MLN T reg cells by affecting the set point of T/HS responsiveness.
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Erlotinib promotes endoplasmic reticulum stress-mediated injury in the intestinal epithelium. Toxicol Appl Pharmacol 2014; 278:45-52. [PMID: 24768708 DOI: 10.1016/j.taap.2014.04.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 04/10/2014] [Accepted: 04/15/2014] [Indexed: 01/23/2023]
Abstract
Erlotinib, a popular drug for treating non-small cell lung cancer (NSCLC), causes diarrhea in approximately 55% of patients receiving this drug. In the present study, we found that erlotinib induced barrier dysfunction in rat small intestine epithelial cells (IEC-6) by increasing epithelial permeability and down-regulating E-cadherin. The mRNA levels of various pro-inflammatory cytokines (Il-6, Il-25 and Il-17f) were increased after erlotinib treatment in IEC-6 cells. Erlotinib concentration- and time-dependently induced apoptosis and endoplasmic reticulum (ER) stress in both IEC-6 and human colon epithelial cells (CCD 841 CoN). Intestinal epithelial injury was also observed in male C57BL/6J mice administrated with erlotinib. Knockdown of C/EBP homologous protein (CHOP) with small interference RNA partially reversed erlotinib-induced apoptosis, production of IL-6 and down-regulation of E-cadherin in cultured intestinal epithelial cells. In conclusion, erlotinib caused ER stress-mediated injury in the intestinal epithelium, contributing to its side effects of diarrhea in patients.
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Du MH, Luo HM, Hu S, Lv Y, Lin ZL, Ma L. Electroacupuncture improves gut barrier dysfunction in prolonged hemorrhagic shock rats through vagus anti-inflammatory mechanism. World J Gastroenterol 2013; 19:5988-5999. [PMID: 24106399 PMCID: PMC3785620 DOI: 10.3748/wjg.v19.i36.5988] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Revised: 07/11/2013] [Accepted: 08/17/2013] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate whether electroacupuncture (EA) at Zusanli (ST36) prevents intestinal barrier and remote organ dysfunction following prolonged hemorrhagic shock through a vagus anti-inflammatory mechanism.
METHODS: Sprague-Dawley rats were subjected to about 45% of total blood volume loss followed by delayed fluid replacement (DFR) with Ringer lactate 3h after hemorrhage. In a first study, rats were randomly divided into six groups: (1) EAN: EA at non-channel acupoints followed by DFR; (2) EA: EA at ST36 after hemorrhage followed by DFR; (3) VGX/EA: vagotomy (VGX) before EA at ST36 and DFR; (4) VGX/EAN: VGX before EAN and DFR; (5) α-bungarotoxin (α-BGT)/EA: intraperitoneal injection of α-BGT before hemorrhage, followed by EA at ST36 and DFR; and (6) α-BGT/EAN group: α-BGT injection before hemorrhage followed by EAN and DFR. Survival and mean arterial pressure (MAP) were monitored over the next 12 h. In a second study, with the same grouping and treatment, cytokine levels in plasma and intestine, organ parameters, gut injury score, gut permeability to 4 kDa FITC-dextran, and expression and distribution of tight junction protein ZO-1 were evaluated.
RESULTS: MAP was significantly lowered after blood loss; EA at ST36 improved the blood pressure at corresponding time points 3 and 12 h after hemorrhage. EA at ST36 reduced tumor necrosis factor-α and interleukin (IL)-6 levels in both plasma and intestine homogenates after blood loss and DFR, while vagotomy or intraperitoneal injection of α-BGT before EA at ST36 reversed its anti-inflammatory effects, and EA at ST36 did not influence IL-10 levels in plasma and intestine. EA at ST36 alleviated the injury of intestinal villus, the gut injury score being significantly lower than that of EAN group (1.85 ± 0.33 vs 3.78 ± 0.59, P < 0.05). EA at ST36 decreased intestinal permeability to FITC-dextran compared with EAN group (856.95 ng/mL ± 90.65 ng/mL vs 2305.62 ng/mL ± 278.32 ng/mL, P < 0.05). EA at ST36 significantly preserved ZO-1 protein expression and localization at 12 h after hemorrhage. However, EA at non-channel acupoints had no such effect, and abdominal vagotomy and α-BGT treatment could weaken or eliminate the effects of EA at ST36. Besides, EA at ST36 decreased blood aminotransferase, MB isoenzyme of creatine kinase and creatinine vs EAN group at corresponding time points. At the end of 12-h experiment, the survival rate of the EA group was significantly higher than that of the other groups.
CONCLUSION: EA at ST36 attenuates the systemic inflammatory response, protects intestinal barrier integrity, improves organ function and survival rate after hemorrhagic shock via activating the cholinergic anti-inflammatory mechanism.
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Garzoni L, Faure C, Frasch M. Fetal cholinergic anti-inflammatory pathway and necrotizing enterocolitis: the brain-gut connection begins in utero. Front Integr Neurosci 2013; 7:57. [PMID: 23964209 PMCID: PMC3737662 DOI: 10.3389/fnint.2013.00057] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 07/18/2013] [Indexed: 12/25/2022] Open
Abstract
Necrotizing enterocolitis (NEC) is an acute neonatal inflammatory disease that affects the intestine and may result in necrosis, systemic sepsis and multisystem organ failure. NEC affects 5-10% of all infants with birth weight ≤ 1500 g or gestational age less than 30 weeks. Chorioamnionitis (CA) is the main manifestation of pathological inflammation in the fetus and is strong associated with NEC. CA affects 20% of full-term pregnancies and upto 60% of preterm pregnancies and, notably, is often an occult finding. Intrauterine exposure to inflammatory stimuli may switch innate immunity cells such as macrophages to a reactive phenotype ("priming"). Confronted with renewed inflammatory stimuli during labour or postnatally, such sensitized cells can sustain a chronic or exaggerated production of proinflammatory cytokines associated with NEC (two-hit hypothesis). Via the cholinergic anti-inflammatory pathway, a neurally mediated innate anti-inflammatory mechanism, higher levels of vagal activity are associated with lower systemic levels of proinflammatory cytokines. This effect is mediated by the α7 subunit nicotinic acetylcholine receptor (α7nAChR) on macrophages. The gut is the most extensive organ innervated by the vagus nerve; it is also the primary site of innate immunity in the newborn. Here we review the mechanisms of possible neuroimmunological brain-gut interactions involved in the induction and control of antenatal intestinal inflammatory response and priming. We propose a neuroimmunological framework to (1) study the long-term effects of perinatal intestinal response to infection and (2) to uncover new targets for preventive and therapeutic intervention.
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Affiliation(s)
- L. Garzoni
- CHU Sainte Justine Research Center, MontrealQC, Canada
- Division of Gastroenterology, Hepatology and Nutrition, CHU Sainte-Justine, MontrealQC, Canada
| | - C. Faure
- CHU Sainte Justine Research Center, MontrealQC, Canada
- Division of Gastroenterology, Hepatology and Nutrition, CHU Sainte-Justine, MontrealQC, Canada
| | - M.G. Frasch
- CHU Sainte Justine Research Center, MontrealQC, Canada
- Department of Obstetrics and Gynaecology, University of MontrealMontreal, QC, Canada
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Enteric glia cells attenuate cytomix-induced intestinal epithelial barrier breakdown. PLoS One 2013; 8:e69042. [PMID: 23840906 PMCID: PMC3698076 DOI: 10.1371/journal.pone.0069042] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 06/04/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Intestinal barrier failure may lead to systemic inflammation and distant organ injury in patients following severe injury. Enteric glia cells (EGCs) have been shown to play an important role in maintaining gut barrier integrity through secretion of S-Nitrosoglutathione (GSNO). We have recently shown than Vagal Nerve Stimulation (VNS) increases EGC activation, which was associated with improved gut barrier integrity. Thus, we sought to further study the mechanism by which EGCs prevent intestinal barrier breakdown utilizing an in vitro model. We postulated that EGCs, through the secretion of GSNO, would improve intestinal barrier function through improved expression and localization of intestinal tight junction proteins. METHODS Epithelial cells were co-cultured with EGCs or incubated with GSNO and exposed to Cytomix (TNF-α, INF-γ, IL-1β) for 24 hours. Barrier function was assessed by permeability to 4kDa FITC-Dextran. Changes in tight junction proteins ZO-1, occludin, and phospho-MLC (P-MLC) were assessed by immunohistochemistry and immunoblot. KEY RESULTS Co-culture of Cytomix-stimulated epithelial monolayers with EGCs prevented increases in permeability and improved expression and localization of occludin, ZO-1, and P-MLC. Further, treatment of epithelial monolayers with GSNO also prevented Cytomix-induced increases in permeability and exhibited a similar improvement in expression and localization of occludin, ZO-1, and P-MLC. CONCLUSIONS & INFERENCES The addition of EGCs, or their secreted mediator GSNO, prevents epithelial barrier failure after injury and improved expression of tight junction proteins. Thus, therapies that increase EGC activation, such as VNS, may be a novel strategy to limit barrier failure in patients following severe injury.
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Parasympathetic stimulation via the vagus nerve prevents systemic organ dysfunction by abrogating gut injury and lymph toxicity in trauma and hemorrhagic shock. Shock 2013; 39:39-44. [PMID: 23247120 DOI: 10.1097/shk.0b013e31827b450d] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We tested if vagus nerve stimulation (VNS) would prevent gut injury, mesenteric lymph toxicity, and systemic multiple organ dysfunction syndrome following trauma-hemorrhagic shock (T/HS). Four groups of experiments were performed. The first tested whether VNS (5 V for 10 min) would protect against T/HS-induced increases in gut and lung permeability as well as neutrophil priming. In the second experiment, mesenteric lymph was collected from rats subjected to T/HS or trauma-sham shock with or without VNS and then injected into naive mice to assess its biologic activity. Lung permeability, neutrophil priming, and red blood cell deformability were measured. Next, the role of the spleen in VNS-mediated protection was tested by measuring gut and lung injury in splenectomized rats subjected to sham or actual VNS. Lastly, the ability of nicotine to replicate the gut-protective effect of VNS was tested. Vagus nerve stimulation protected against T/HS-induced gut injury, lung injury, and neutrophil priming (P < 0.05). Not only did VNS limit organ injury after T/HS, but in contrast to the mesenteric lymph collected from the sham-VNS T/HS rats, the mesenteric lymph from the VNS T/HS rats did not cause lung injury, neutrophil priming, or loss of red blood cell deformability (P < 0.05) when injected into naive mice. Removal of the spleen did not prevent the protective effects of VNS on gut or lung injury after T/HS. Similar to VNS, the administration of nicotine also protected the gut from injury after T/HS. Vagus nerve stimulation prevents T/HS-induced gut injury, lung injury, neutrophil priming, and the production of biologically active mesenteric lymph. This protective effect of VNS was not dependent on the spleen but appeared to involve a cholinergic nicotinic receptor, because its beneficial effects could be replicated with nicotine.
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Lu X, Costantini T, Lopez NE, Wolf PL, Hageny AM, Putnam J, Eliceiri B, Coimbra R. Vagal nerve stimulation protects cardiac injury by attenuating mitochondrial dysfunction in a murine burn injury model. J Cell Mol Med 2013; 17:664-71. [PMID: 23577721 PMCID: PMC3822819 DOI: 10.1111/jcmm.12049] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 02/07/2013] [Indexed: 01/29/2023] Open
Abstract
Mitochondria play a central role in the integration and execution of a wide variety of apoptotic signals. In the present study, we examined the deleterious effects of burn injury on heart tissue. We explored the effects of vagal nerve stimulation (VNS) on cardiac injury in a murine burn injury model, with a focus on the protective effect of VNS on mitochondrial dysfunction in heart tissue. Mice were subjected to a 30% total body surface area, full-thickness steam burn followed by right cervical VNS for 10 min. and compared to burn alone. A separate group of mice were treated with the M3-muscarinic acetylcholine receptor (M3-AchR) antagonist 4-DAMP or phosphatidylinositol 3 Kinase (PI3K) inhibitor LY294002 prior to burn and VNS. Heart tissue samples were collected at 6 and 24 hrs after injury to measure changes in apoptotic signalling pathways. Burn injury caused significant cardiac pathological changes, cardiomyocyte apoptosis, mitochondrial swelling and decrease in myocardial ATP content at 6 and 24 hrs after injury. These changes were significantly attenuated by VNS. VNS inhibited release of pro-apoptotic protein cytochrome C and apoptosis-inducing factor from mitochondria to cytosol by increasing the expression of Bcl-2, and the phosphorylation level of Bad (pBad136) and Akt (pAkt308). These protective changes were blocked by 4-DAMP or LY294002. We demonstrated that VNS protected against burn injury–induced cardiac injury by attenuating mitochondria dysfunction, likely through the M3-AchR and the PI3K/Akt signalling pathways.
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Affiliation(s)
- Xiaojiong Lu
- Division of Trauma, Surgical Critical Care and Burns, Department of Surgery, University of California San Diego Health Sciences, San Diego, CA 92103, USA
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Electroacupuncture at Zusanli (ST36) Prevents Intestinal Barrier and Remote Organ Dysfunction following Gut Ischemia through Activating the Cholinergic Anti-Inflammatory-Dependent Mechanism. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:592127. [PMID: 23662144 PMCID: PMC3638586 DOI: 10.1155/2013/592127] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 03/18/2013] [Indexed: 02/08/2023]
Abstract
This study investigated the protective effect and mechanism of electroacupuncture at ST36 points on the intestinal barrier dysfunction and remote organ injury after intestinal ischemia and reperfusion injury in rats. Rats were subjected to gut ischemia for 30 min, and then received electroacupuncture for 30 min with or without abdominal vagotomy or intraperitoneal administration of cholinergic α 7 nicotinic acetylcholine receptor ( α 7nAChR) inhibitor. Then we compared its effects with electroacupuncture at nonchannel points, vagal nerve stimulation, or intraperitoneal administration of cholinergic agonist. Cytokine levels in plasma and tissue of intestine, lung, and liver were assessed 60 min after reperfusion. Intestinal barrier injury was detected by histology, gut injury score, the permeability to 4 kDa FITC-dextran, and changes in tight junction protein ZO-1 using immunofluorescence and Western blot. Electroacupuncture significantly lowered the levels of tumor necrosis factor- α and interleukin-8 in plasma and organ tissues, decreased intestinal permeability to FITC-dextran, and prevented changes in ZO-1 protein expression and localization. However, abdominal vagotomy or intraperitoneal administration of cholinergic α 7nAChR inhibitor reversed these effects of electroacupuncture. These findings suggest that electroacupuncture attenuates the systemic inflammatory response through protection of intestinal barrier integrity after intestinal ischemia injury in the presence of an intact vagus nerve.
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Reys LG, Ortiz-Pomales YT, Lopez N, Cheadle G, de Oliveira PG, Eliceiri B, Bansal V, Costantini TW, Coimbra R. Uncovering the neuroenteric-pulmonary axis: vagal nerve stimulation prevents acute lung injury following hemorrhagic shock. Life Sci 2013; 92:783-92. [PMID: 23439327 DOI: 10.1016/j.lfs.2013.02.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 02/06/2013] [Accepted: 02/12/2013] [Indexed: 12/23/2022]
Abstract
AIMS Trauma/hemorrhagic shock (T/HS) induced gut injury is known to initiate a systemic inflammatory response which can lead to secondary lung injury. We have shown that vagal nerve stimulation (VNS) protects intestinal epithelial integrity after a severe burn insult. We hypothesize that VNS will protect the lung from injury following T/HS by preventing intestinal barrier failure. MAIN METHODS Male Balb/c mice were subjected to a T/HS model with and without cervical VNS. Intestinal injury was evaluated by measuring changes in gut barrier function and tight junction protein localization. Lung injury was evaluated using histology and markers of lung inflammation. Using NF-kB-luciferase (NF-kB-luc) transgenic mice, NF-kb-DNA binding was measured by photon emission analysis at 4 after injury. KEY FINDINGS T/HS is associated gut injury characterized by histologic injury, increased epithelial permeability, and altered localization of gut tight junction proteins. Cervical VNS prevented the T/HS-induced changes in gut barrier integrity. Gut injury after T/HS was associated with acute lung injury at 24 h characterized by histologic injury, increased number of MPO positive stained cells and MPO enzymatic activity, and increased ICAM-1 expression in lung endothelium. VNS decreased T/HS-induced lung injury with a marked decrease in lung inflammation compared to T/HS alone. Lungs harvested from NF-kB-luc mice at 4h post VNS+T/HS demonstrated decreased DNA binding of NF-kB compared to T/HS alone as measured by changes in bioluminescence. SIGNIFICANCE VNS is effective in protecting against acute lung injury caused by hemorrhagic shock through its ability to prevent gut barrier dysfunction.
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Vagal nerve stimulation blocks peritoneal macrophage inflammatory responsiveness after severe burn injury. Shock 2012; 38:294-300. [PMID: 22683732 DOI: 10.1097/shk.0b013e31825f5fb2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Large surface area burn injuries lead to activation of the innate immune system, which can be blocked by parasympathetic inputs mediated by the vagus nerve. We hypothesized that vagal nerve stimulation (VNS) would alter the inflammatory response of peritoneal macrophages after severe burn injury. Male BALB/c mice underwent right cervical VNS before 30% total body surface area steam burn and were compared with animals subjected to burn alone. Peritoneal macrophages were harvested at several time points following injury and exposed to lipopolysaccharide (LPS) in culture conditions. The inflammatory response of peritoneal macrophages was measured by analyzing changes in nuclear factor κB p65 phosphorylation using flow cytometry. We found that peritoneal macrophages isolated from mice subjected to burn injury were hyperresponsive to LPS challenge, suggesting burn-induced macrophage activation. We identified a protective role for VNS in blocking peritoneal macrophage activation. Analysis of the phosphorylation state of nuclear factor κB pathway mediator, p65 Rel A, revealed a VNS-mediated reduction in p65 phosphorylation levels after exposure to LPS compared with burn alone. In combination, these studies suggest VNS mediates the inflammatory response in peritoneal macrophages by affecting the set point of LPS responsiveness.
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Costantini TW, Eliceiri BP, Putnam JG, Bansal V, Baird A, Coimbra R. Intravenous phage display identifies peptide sequences that target the burn-injured intestine. Peptides 2012; 38:94-9. [PMID: 22960048 PMCID: PMC4524536 DOI: 10.1016/j.peptides.2012.08.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 08/22/2012] [Accepted: 08/22/2012] [Indexed: 12/18/2022]
Abstract
The injured intestine is responsible for significant morbidity and mortality after severe trauma and burn; however, targeting the intestine with therapeutics aimed at decreasing injury has proven difficult. We hypothesized that we could use intravenous phage display technology to identify peptide sequences that target the injured intestinal mucosa in a murine model, and then confirm the cross-reactivity of this peptide sequence with ex vivo human gut. Four hours following 30% TBSA burn we performed an in vivo, intravenous systemic administration of phage library containing 10(12) phage in balb/c mice to biopan for gut-targeting peptides. In vivo assessment of the candidate peptide sequences identified after 4 rounds of internalization was performed by injecting 1×10(12) copies of each selected phage clone into sham or burned animals. Internalization into the gut was assessed using quantitative polymerase chain reaction. We then incubated this gut-targeting peptide sequence with human intestine and visualized fluorescence using confocal microscopy. We identified 3 gut-targeting peptide sequences which caused collapse of the phage library (4-1: SGHQLLLNKMP, 4-5: ILANDLTAPGPR, 4-11: SFKPSGLPAQSL). Sequence 4-5 was internalized into the intestinal mucosa of burned animals 9.3-fold higher than sham animals injected with the same sequence (2.9×10(5)vs. 3.1×10(4) particles per mg tissue). Sequences 4-1 and 4-11 were both internalized into the gut, but did not demonstrate specificity for the injured mucosa. Phage sequence 4-11 demonstrated cross-reactivity with human intestine. In the future, this gut-targeting peptide sequence could serve as a platform for the delivery of biotherapeutics.
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Affiliation(s)
| | | | | | | | | | - Raul Coimbra
- Corresponding author at: 200W. Arbor Drive, #8896 San Diego, CA 92103-8896, United States. Tel.: +1 619 543 7100; fax: +1 619 543 7202. (R. Coimbra)
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