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Cao YY, Qiao Y, Wang ZH, Chen Q, Qi YP, Lu ZM, Wang Z, Lu WH. The Polo-Like Kinase 1-Mammalian Target of Rapamycin Axis Regulates Autophagy to Prevent Intestinal Barrier Dysfunction During Sepsis. THE AMERICAN JOURNAL OF PATHOLOGY 2023; 193:296-312. [PMID: 36509119 DOI: 10.1016/j.ajpath.2022.11.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/19/2022] [Accepted: 11/04/2022] [Indexed: 12/13/2022]
Abstract
The intestines play a crucial role in the development of sepsis. The balance between autophagy and apoptosis in intestinal epithelial cells is dynamic and determines intestinal permeability. The present study focused on the potential role of autophagy in sepsis-induced intestinal barrier dysfunction and explored the mechanisms in vivo and in vitro. Excessive apoptosis in intestinal epithelia and a disrupted intestinal barrier were observed in septic mice. Promoting autophagy with rapamycin reduced intestinal epithelial apoptosis and restored intestinal barrier function, presenting as decreased serum diamine oxidase (DAO) and fluorescein isothiocyanate-dextran 40 (FD40) levels and increased expression of zonula occludens-1 (ZO-1) and Occludin. Polo-like kinase 1 (PLK1) knockdown in mice ameliorated intestinal epithelial apoptosis and the intestinal barrier during sepsis, whereas these effects were reduced with chloroquine and enhanced with rapamycin. PLK1 also promoted cell autophagy and improved lipopolysaccharide-induced apoptosis and high permeability in vitro. Moreover, PLK1 physically interacted with mammalian target of rapamycin (mTOR) and participated in reciprocal regulatory crosstalk in intestinal epithelial cells during sepsis. This study provides novel insight into the role of autophagy in sepsis-induced intestinal barrier dysfunction and indicates that the PLK1-mTOR axis may be a promising therapeutic target for sepsis.
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Affiliation(s)
- Ying-Ya Cao
- Department of Critical Care Medicine, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China; Anhui Province Clinical Research Center for Critical Care Medicine (Respiratory Disease), Wuhu, China
| | - Yang Qiao
- Department of Anesthesiology, Zhejiang Provincial Hospital of Traditional Chinese Medicine, Hangzhou, China
| | - Zhong-Han Wang
- Department of Critical Care Medicine, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China; Anhui Province Clinical Research Center for Critical Care Medicine (Respiratory Disease), Wuhu, China
| | - Qun Chen
- Department of Critical Care Medicine, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China; Anhui Province Clinical Research Center for Critical Care Medicine (Respiratory Disease), Wuhu, China
| | - Yu-Peng Qi
- Department of Critical Care Medicine, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China; Anhui Province Clinical Research Center for Critical Care Medicine (Respiratory Disease), Wuhu, China
| | - Zi-Meng Lu
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Zhen Wang
- Department of General Practice, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Wei-Hua Lu
- Department of Critical Care Medicine, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China; Anhui Province Clinical Research Center for Critical Care Medicine (Respiratory Disease), Wuhu, China.
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Xin J. Critical signaling pathways governing colitis-associated colorectal cancer: Signaling, therapeutic implications, and challenges. Dig Liver Dis 2023; 55:169-177. [PMID: 36002360 DOI: 10.1016/j.dld.2022.08.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 07/05/2022] [Accepted: 08/03/2022] [Indexed: 02/01/2023]
Abstract
Long-term colitis in people with inflammatory bowel disease (IBD) may lead to colon cancer called colitis-associated colorectal cancer (CAC). Since the advent of preclinical prototypes of CAC, various immunological messaging cascades have been identified as implicated in developing this disease. The toll-like receptor (TLR)s, Janus kinase (JAK)-signal transducer and activator of transcription (STAT), Nuclear factor-kappa B (NF-κB), mammalian target of rapamycin complex (mTOR), autophagy, and oxidative stress are only a few of the molecular mechanisms that have been recognized as major components to CAC progression. These pathways may also represent attractive medicinal candidates for the prevention and management of CAC. CAC signaling mechanisms at the molecular level and how their dysregulation may cause illness are summarized in this comprehensive overview.
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Affiliation(s)
- Jiang Xin
- Department of Gastrointestinal Surgery, The Third People's hospital of Qingdao, 266000, China.
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Effects of Herb-Partitioned Moxibustion on Autophagy and Immune Activity in the Colon Tissue of Rats with Crohn’s Disease. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:3534874. [PMID: 35126598 PMCID: PMC8816589 DOI: 10.1155/2022/3534874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 01/11/2022] [Indexed: 11/18/2022]
Abstract
Objective To investigate the mechanism of action of herb-partitioned moxibustion on CD from the perspective of autophagy and immunity. Methods The expression of microtubule-associated protein LC3II and SQSTM1/p62 in the colon tissues was detected by immunohistochemistry. Western blot was used to detect the expression of autophagic and immune-related proteins in the colon, such as LC3II, SQSTM1/p62, Beclin1, ATG16L1, NOD2, IRGM, IL-1β, IL-17, and TNF-β. mRNA levels of immune factors, such as IL-1β, IL-17, and TNF-β, and autophagy signaling molecules, such as PI3KC, AKT1, LKB1, and mTOR, were detected by RT-qPCR. Results Herb-partitioned moxibustion reduced the protein levels of ATG16L1, NOD2, IRGM, LC3II, and Beclin1 (P < 0.01) and both the protein and mRNA levels of IL-1β, IL-17, and TNF-β in CD rats (P < 0.01 or P < 0.05), and it also increased the expression of SQSTM1/p62 protein (P < 0.01). The modulatory effects of herb-partitioned moxibustion on ATG16L1, NOD2, IRGM, LC3II, TNF-β, and IL-17 protein and IL-1β protein and mRNA were better than those of mesalazine (P < 0.01 or P < 0.05). Herb-partitioned moxibustion also reduced colon PI3KC, AKT1, and LKB1 mRNA expressions in CD rats (P < 0.01 or P < 0.05) and increased mTOR protein expression (P < 0.05). And the modulatory effect of herb-partitioned moxibustion on AKT1 mRNA was better than that of mesalazine (P < 0.05). Conclusion Herb-partitioned moxibustion may inhibit excessively activated autophagy and modulate the expression of immune-related factors by regulating the LKB1-mTOR-PI3KC signal transduction networks, thereby alleviating intestinal inflammation in CD rats.
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Di Gregorio J, Robuffo I, Spalletta S, Giambuzzi G, De Iuliis V, Toniato E, Martinotti S, Conti P, Flati V. The Epithelial-to-Mesenchymal Transition as a Possible Therapeutic Target in Fibrotic Disorders. Front Cell Dev Biol 2020; 8:607483. [PMID: 33409282 PMCID: PMC7779530 DOI: 10.3389/fcell.2020.607483] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/25/2020] [Indexed: 12/11/2022] Open
Abstract
Fibrosis is a chronic and progressive disorder characterized by excessive deposition of extracellular matrix, which leads to scarring and loss of function of the affected organ or tissue. Indeed, the fibrotic process affects a variety of organs and tissues, with specific molecular background. However, two common hallmarks are shared: the crucial role of the transforming growth factor-beta (TGF-β) and the involvement of the inflammation process, that is essential for initiating the fibrotic degeneration. TGF-β in particular but also other cytokines regulate the most common molecular mechanism at the basis of fibrosis, the Epithelial-to-Mesenchymal Transition (EMT). EMT has been extensively studied, but not yet fully explored as a possible therapeutic target for fibrosis. A deeper understanding of the crosstalk between fibrosis and EMT may represent an opportunity for the development of a broadly effective anti-fibrotic therapy. Here we report the evidences of the relationship between EMT and multi-organ fibrosis, and the possible therapeutic approaches that may be developed by exploiting this relationship.
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Affiliation(s)
- Jacopo Di Gregorio
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States
| | - Iole Robuffo
- Institute of Molecular Genetics, National Research Council, Section of Chieti, Chieti, Italy
| | - Sonia Spalletta
- Department of Clinical Pathology, E. Profili Hospital, Fabriano, Ancona, Italy
| | - Giulia Giambuzzi
- Department of Medical and Oral Sciences and Biotechnologies, University “G. d’Annunzio”, Chieti, Italy
| | - Vincenzo De Iuliis
- Department of Medical and Oral Sciences and Biotechnologies, University “G. d’Annunzio”, Chieti, Italy
| | - Elena Toniato
- Department of Medical and Oral Sciences and Biotechnologies, University “G. d’Annunzio”, Chieti, Italy
| | - Stefano Martinotti
- Department of Medical and Oral Sciences and Biotechnologies, University “G. d’Annunzio”, Chieti, Italy
| | - Pio Conti
- Postgraduate Medical School, University of Chieti-Pescara, Chieti, Italy
| | - Vincenzo Flati
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
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Li X, Tan CP, Liu YF, Xu YJ. Interactions between Food Hazards and Intestinal Barrier: Impact on Foodborne Diseases. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:14728-14738. [PMID: 33289375 DOI: 10.1021/acs.jafc.0c07378] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The intestine is an important digestive organ of the human body, and its barrier is the guardian of the body from the external environment. The impairment of the intestinal barrier is believed to be an important determinant in various foodborne diseases. Food hazards can lead to the occurrence of many foodborne diseases represented by inflammation. Therefore, understanding the mechanisms of the impact of the food hazards on intestinal barriers is essential for promoting human health. This review examined the relationship between food hazards and the intestinal barrier in three aspects: apoptosis, imbalance of gut microbiota, and pro-inflammatory cytokines. The mechanism of dysfunctional gut microbiota caused by food hazards was also discussed. This review discusses the interaction among food hazards, intestinal barrier, and foodborne diseases and, thus, offers a new thought to deal with foodborne disease.
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Affiliation(s)
- Xue Li
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, National Engineering Laboratory for Cereal Fermentation Technology, Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, People's Republic of China
| | - Chin-Ping Tan
- Department of Food Technology, Faculty of Food Science and Technology, University Putra Malaysia, Selangor 410500, Malaysia
| | - Yuan-Fa Liu
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, National Engineering Laboratory for Cereal Fermentation Technology, Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, People's Republic of China
| | - Yong-Jiang Xu
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, National Engineering Laboratory for Cereal Fermentation Technology, Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, People's Republic of China
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Pan HH, Zhou XX, Ma YY, Pan WS, Zhao F, Yu MS, Liu JQ. Resveratrol alleviates intestinal mucosal barrier dysfunction in dextran sulfate sodium-induced colitis mice by enhancing autophagy. World J Gastroenterol 2020; 26:4945-4959. [PMID: 32952341 PMCID: PMC7476174 DOI: 10.3748/wjg.v26.i33.4945] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/27/2020] [Accepted: 08/12/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Intestinal mucosal barrier dysfunction plays an important role in the pathogenesis of ulcerative colitis (UC). Recent studies have revealed that impaired autophagy is associated with intestinal mucosal dysfunction in the mucosa of colitis mice. Resveratrol exerts anti-inflammatory functions by regulating autophagy.
AIM To investigate the effect and mechanism of resveratrol on protecting the integrity of the intestinal mucosal barrier and anti-inflammation in dextran sulfate sodium (DSS)-induced ulcerative colitis mice.
METHODS Male C57BL/6 mice were divided into four groups: negative control group, DSS model group, DSS + resveratrol group, and DSS + 5-aminosalicylic acid group. The severity of colitis was assessed by the disease activity index, serum inflammatory cytokines were detected by enzyme-linked immunosorbent assay. Colon tissues were stained with haematoxylin and eosin, and mucosal damage was evaluated by mean histological score. The expression of occludin and ZO-1 in colon tissue was evaluated using immunohistochemical analysis. In addition, the expression of autophagy-related genes was determined using reverse transcription-polymerase chain reaction and Western-blot, and morphology of autophagy was observed by transmission electron microscopy.
RESULTS The resveratrol treatment group showed a 1.72-fold decrease in disease activity index scores and 1.42, 3.81, and 1.65-fold decrease in the production of the inflammatory cytokine tumor necrosis factor-α, interleukin-6 and interleukin-1β, respectively, in DSS-induced colitis mice compared with DSS group (P < 0.05). The expressions of the tight junction proteins occludin and ZO-1 in DSS model group were decreased, and were increased in resveratrol-treated colitis group. Resveratrol also increased the levels of LC3B (by 1.39-fold compared with DSS group) and Beclin-1 (by 1.49-fold compared with DSS group) (P < 0.05), as well as the number of autophagosomes, which implies that the resveratrol may alleviate intestinal mucosal barrier dysfunction in DSS-induced UC mice by enhancing autophagy.
CONCLUSION Resveratrol treatment decreased the expression of inflammatory factors, increased the expression of tight junction proteins and alleviated UC intestinal mucosal barrier dysfunction; this effect may be achieved by enhancing autophagy in intestinal epithelial cells.
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Affiliation(s)
- Hang-Hai Pan
- Department of Gastroenterology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou 310014, Zhejiang Province, China
| | - Xin-Xin Zhou
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, Zhejiang Province, China
| | - Ying-Yu Ma
- Key Laboratory of Gastroenterology of Zhejiang Province, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou 310014, Zhejiang Province, China
| | - Wen-Sheng Pan
- Department of Gastroenterology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou 310014, Zhejiang Province, China
| | - Fei Zhao
- Department of Gastroenterology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou 310014, Zhejiang Province, China
| | - Mo-Sang Yu
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, Zhejiang Province, China
| | - Jing-Quan Liu
- Critical Care Unit, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou 310014, Zhejiang Province, China
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Crohn's Disease: Potential Drugs for Modulation of Autophagy. ACTA ACUST UNITED AC 2019; 55:medicina55060224. [PMID: 31146413 PMCID: PMC6630681 DOI: 10.3390/medicina55060224] [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: 01/29/2019] [Revised: 02/26/2019] [Accepted: 05/23/2019] [Indexed: 12/12/2022]
Abstract
Autophagy is an intracellular process whereby cytoplasmic constituents are degraded within lysosomes. Autophagy functions to eliminate unwanted or damaged materials such as proteins and organelles as their accumulation would be harmful to the cellular system. Autophagy also acts as a defense mechanism against invading pathogens and plays an important role in innate and adaptive immunity. In physiological processes, autophagy is involved in the regulation of tissue development, differentiation and remodeling, which are essential for maintaining cellular homeostasis. Recent studies have demonstrated that autophagy is linked to various diseases and involved in pathophysiological roles, such as adaptation during starvation, anti-aging, antigen presentation, tumor suppression and cell death. The modulation of autophagy has shown greatest promise in Crohn’s disease as most of autophagy drugs involved in these diseases are currently under clinical trials and some has been approved by Food and Drug Administration. This review article discusses autophagy and potential drugs that are currently available for its modulation in Crohn’s disease.
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The role of autophagy in colitis-associated colorectal cancer. Signal Transduct Target Ther 2018; 3:31. [PMID: 30510778 PMCID: PMC6265276 DOI: 10.1038/s41392-018-0031-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/04/2018] [Accepted: 10/17/2018] [Indexed: 12/12/2022] Open
Abstract
Autophagy is an evolutionarily conserved catabolic process that eliminates harmful components through lysosomal degradation. In addition to its role in maintaining cellular homeostasis, autophagy is critical to pathological processes, such as inflammation and cancer. Colitis-associated colorectal cancer (CAC) is a specific type of colorectal cancer that develops from long-standing colitis in inflammatory bowel disease (IBD) patients. Accumulating evidence indicates that autophagy of microenvironmental cells plays different but vital roles during tumorigenesis and CAC development. Herein, after summarizing the recent advances in understanding the role of autophagy in regulating the tumor microenvironment during different CAC stages, we draw the following conclusions: autophagy in intestinal epithelial cells inhibits colitis and CAC initiation but promotes CAC progression; autophagy in macrophages inhibits colitis, but its function on CAC is currently unclear; autophagy in neutrophils and cancer-associated fibroblasts (CAFs) promotes both colitis and CAC; autophagy in dendritic cells (DCs) and T cells represses both colitis and CAC; autophagy in natural killer cells (NKs) inhibits colitis, but promotes CAC; and autophagy in endothelial cells plays a controversial role in colitis and CAC. Understanding the role of autophagy in specific compartments of the tumor microenvironment during different stages of CAC may provide insight into malignant transformation, tumor progression, and combination therapy strategies for CAC.
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Escherichia coli O157:H7 suppresses host autophagy and promotes epithelial adhesion via Tir-mediated and cAMP-independent activation of protein kinase A. Cell Death Discov 2017; 3:17055. [PMID: 28975041 PMCID: PMC5624281 DOI: 10.1038/cddiscovery.2017.55] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 07/07/2017] [Indexed: 11/18/2022] Open
Abstract
Autophagy is a pivotal innate immune response that not only degrades cytosolic components, but also serves as one of the critical antimicrobial mechanisms eliminating intracellular pathogens. However, its role in host defense against extracellular pathogens is largely unknown. Here we showed that E. coli O157:H7 altered autophagy to evade host defense and facilitate adhesion. Enhancing host cell autophagy with tumor necrosis factor (TNF), host starvation or rapamycin reduced the adherence of E. coli O157:H7 to HT-29 cells. As a key regulator of autophagy, protein kinase A (PKA) was activated by E. coli O157:H7 infection. PKA inhibition by H89 abrogated E. coli O157:H7 inhibition of autophagy and prevented bacterial epithelial adhesion. Thus, PKA had a mediatory role in blocking autophagy and E. coli O157:H7 epithelial adhesion. Furthermore, deletion of translocated intimin receptor (tir) prevented PKA activation, whereas ectopic tir expression in a Δtir mutant strain restored its ability to activate PKA and inhibited autophagy in host cells. This indicated that Tir and PKA played pivotal roles in manipulating host autophagy during infection. Consistent with autophagy inhibition, E. coli O157:H7 infection inhibited endoplasmic reticulum (ER) stress in HT-29 cells, which was reversed by TNF, starvation, or H89 treatment. Additionally, E. coli O157:H7-induced PKA activation suppressed extracellular signal-regulated kinase 1/2 (ERK1/2) activation and enhanced phosphatidylinositol 3-kinase/Akt (PI3K/Akt) signaling, thereby repressing autophagic signaling. Conversely, PKA inhibition prevented downregulation of ERK1/2 signaling due to E. coli O157:H7 infection. In summary, E. coli O157:H7 inhibited host autophagy via Tir-mediated PKA activation that favored bacterial persistence on intestinal epithelial cell surfaces.
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Zhang C, Yan J, Xiao Y, Shen Y, Wang J, Ge W, Chen Y. Inhibition of Autophagic Degradation Process Contributes to Claudin-2 Expression Increase and Epithelial Tight Junction Dysfunction in TNF-α Treated Cell Monolayers. Int J Mol Sci 2017; 18:157. [PMID: 28106723 PMCID: PMC5297790 DOI: 10.3390/ijms18010157] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/01/2017] [Accepted: 01/10/2017] [Indexed: 02/06/2023] Open
Abstract
Tight junction dysfunction plays a vital role in some chronic inflammatory diseases. Pro-inflammatory cytokines, especially tumor necrosis factor alpha (TNF-α), act as important factors in intestinal epithelial tight junction dysfunction during inflammatory conditions. Autophagy has also been shown to be crucial in tight junction function and claudin-2 expression, but whether autophagy has an effect on the change of claudin-2 expression and tight junction function induced by TNF-α is still unknown. To answer this question, we examined the expression of claudin-2 protein, transepithelial electrical resistance (TER), and permeability of cell monolayers, autophagy flux change, and lysosomal pH after TNF-α with or without PP242 treatment. Our study showed that claudin-2 expression, intestinal permeability, microtubule-associated protein 1 light chain 3B II (LC3B-II) and sequestosome 1 (P62) expression largely increased while TER values decreased in TNF-α treated cell monolayers. Further research using 3-methyladenine (3-MA), bafilomycin A1, and ad-mCherry-GFP-LC3B adenovirus demonstrated that LC3B-II increase induced by TNF-α was attributed to the inhibition of autophagic degradation. Moreover, both qualitative and quantitative method confirmed the increase of lysosomal pH, and mammalian target of rapamycin (mTOR) inhibitor PP242 treatment relieved this elevation. Moreover, PP242 treatment also alleviated the change of autophagy flux, TER, and claudin-2 expression induced by TNF-α. Therefore, we conclude that increase of claudin-2 levels and intestinal epithelial tight junction dysfunction are partly caused by the inhibition of autophagic degradation in TNF-α treated cell monolayers.
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Affiliation(s)
- Cong Zhang
- Department of Gastroenterology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China.
| | - Junkai Yan
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai Institute for Pediatric Research, Shanghai 200092, China.
| | - Yongtao Xiao
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai Institute for Pediatric Research, Shanghai 200092, China.
| | - Yujie Shen
- Department of Gastroenterology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China.
| | - Jiazheng Wang
- Department of Gastroenterology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China.
| | - Wensong Ge
- Department of Gastroenterology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China.
| | - Yingwei Chen
- Department of Gastroenterology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China.
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai Institute for Pediatric Research, Shanghai 200092, China.
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Wan SX, Shi B, Lou XL, Liu JQ, Ma GG, Liang DY, Ma S. Ghrelin protects small intestinal epithelium against sepsis-induced injury by enhancing the autophagy of intestinal epithelial cells. Biomed Pharmacother 2016; 83:1315-1320. [PMID: 27571874 DOI: 10.1016/j.biopha.2016.08.048] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/18/2016] [Accepted: 08/18/2016] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Ghrelin is a hormone that protects against hypoxic injury of cardiac cells by inducing autophagy, but the role of autophagy in sepsis remains unclear. This study aimed to evaluate whether ghrelin could enhance autophagy in rats with intestinal sepsis. METHODS The cecal ligation and perforation (CLP) method was used to induce sepsis in Sprague-Dawley rats. The rats were assigned to four groups: normal group, sham-operated group, sepsis group, and Ghrelin-treated group. Sera and small intestinal tissues were collected from all groups. The sepsis was evaluated by histological analysis, and autophagy of small intestinal epithelial cells was assessed by electron microscopy, immunofluorescence, and biochemical methods. RESULTS The expression of autophagy-associated proteins such as LC3, Atg 7 and Beclin 1 increased by 8h post-CLP and declined to basal levels by 12h post-CLP. The expression of LC3, Atg 7 and Beclin 1 in Ghrelin-treated rats was higher than that in rats with sepsis. Furthermore, compared to rats with sepsis, Ghrelin-treated rats showed significantly reduced intestinal mucosa injury at 20h post-CLP. CONCLUSION Autophagy is induced in the early stages of sepsis. Ghrelin could enhance the autophagy of intestinal epithelial cells in rats with sepsis and protect the small intestinal epithelium against sepsis-induced injury.
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Affiliation(s)
- Sheng-Xia Wan
- The No. 4 Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Bin Shi
- Songjiang Hospital, Affiliated with First People's Hospital, Shanghai Jiaotong University, Critical Care Unit, Shanghai, China.
| | - Xiao-Li Lou
- Songjiang Hospital, Affiliated with First People's Hospital, Shanghai Jiaotong University, Central Laboratory, Shanghai, China
| | - Jing-Quan Liu
- Zhejiang Provincial People's Hospital, Critical Care Unit, Hanzhou, China
| | - Guo-Guang Ma
- Zhongshan Hospital Affiliated with FuDan University, Critical Care Unit, Shanghai, China
| | - Dong-Yu Liang
- Songjiang Hospital, Affiliated with First People's Hospital, Shanghai Jiaotong University, Central Laboratory, Shanghai, China
| | - Shuang Ma
- Songjiang Hospital, Affiliated with First People's Hospital, Shanghai Jiaotong University, Critical Care Unit, Shanghai, China
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Yamagata K, Xie Y, Suzuki S, Tagami M. Epigallocatechin-3-gallate inhibits VCAM-1 expression and apoptosis induction associated with LC3 expressions in TNFα-stimulated human endothelial cells. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2015; 22:431-437. [PMID: 25925964 DOI: 10.1016/j.phymed.2015.01.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/18/2015] [Accepted: 01/27/2015] [Indexed: 06/04/2023]
Abstract
Tumor necrosis factor alpha (TNF-α) promotes the expression of adhesion molecules and induces endothelial dysfunction, a process that can lead to atherosclerosis. Green tea consumption can inhibit endothelial dysfunction and attenuate the development of arteriosclerosis. The purpose of this study was to examine whether epigallocatechin-3-gallate (EGCG) prevents TNF-α-dependent endothelial dysfunction. Here, we compared the regulatory effects of the green tea components EGCG and L-theanine against TNF-α-induced stimulation of adhesion molecule expression and apoptosis induction, which is associated with autophagy. Monocytic cell adhesion to human endothelial cells was measured using a fluorescently-labeled cell line, U-937. Caspase 3/7 activity was examined with a fluorescent probe and fluorescence microscopy. In addition, we analyzed the expression of several genes by RT-PCR. TNF-α-modulation of LC3 and VCAM1 protein levels were investigated by Western blot (WB). TNF-α induced adhesion of U937 cells to endothelial cells, and gene expression associated with adhesion molecules and apoptosis. On the other hand, EGCG and L-theanine inhibited TNF-α-induced adhesion of U937 cells to endothelial cells and inhibited increases in ICAM1, CCL2 and VCAM1 expression. Furthermore, EGCG and L-theanine inhibited TNF-α-induced apoptosis-related gene expression (e.g., CASP9), and caspase activity while inhibiting TNFα-induced VCAM1, LC3A and LC3B protein expression. Meanwhile, treatment of endothelial cells with autophagy inhibitor 3-methyladenine (3-MA) blocked EGCG-induced expression of CASP9. Together, these results indicate that EGCG can modulate TNF-α-induced monocytic cell adhesion, apoptosis and autophagy. We thus conclude that EGCG might be beneficial for inhibiting TNF-α-mediated human endothelial disorders by affecting LC3 expression-related processes.
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Affiliation(s)
- Kazuo Yamagata
- Department of Food Bioscience and Biotechnology, College of Bioresource Sciences, Nihon University (NUBS), Fujisawa, Japan.
| | - Yajie Xie
- Department of Food Bioscience and Biotechnology, College of Bioresource Sciences, Nihon University (NUBS), Fujisawa, Japan
| | - Sayaka Suzuki
- Department of Food Bioscience and Biotechnology, College of Bioresource Sciences, Nihon University (NUBS), Fujisawa, Japan
| | - Motoki Tagami
- Department of Internal Medicine, Sanraku Hospital, Chiyoda-Ku, Tokyo, Japan
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Zemljic M, Pejkovic B, Krajnc I, Lipovsek S. Biological pathways involved in the development of inflammatory bowel disease. Wien Klin Wochenschr 2014; 126:626-33. [PMID: 25256178 DOI: 10.1007/s00508-014-0592-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 08/09/2014] [Indexed: 02/07/2023]
Abstract
Apoptosis, autophagy and necrosis are three distinct functional types of the mammalian cell death network. All of them are characterized by a number of cell's morphological changes. The inappropriate induction of cell death is involved in the pathogenesis of a number of diseases.Pathogenesis of inflammatory bowel diseases (ulcerative colitis, Crohn's disease) includes an abnormal immunological response to disturbed intestinal microflora. One of the most important reason in pathogenesis of chronic inflammatory disease and subsequent multiple organ pathology is a barrier function of the gut, regulating cellular viability. Recent findings have begun to explain the mechanisms by which intestinal epithelial cells are able to survive in such an environment and how loss of normal regulatory processes may lead to inflammatory bowel disease (IBD).This review focuses on the regulation of biological pathways in development and homeostasis in IBD. Better understanding of the physiological functions of biological pathways and their influence on inflammation, immunity, and barrier function will simplify our expertice of homeostasis in the gastrointestinal tract and in upgrading diagnosis and treatment.
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Affiliation(s)
- Mateja Zemljic
- Institute of Anatomy, Histology and Embryology, Faculty of Medicine, University of Maribor, Ljubljanska 5, 2000, Maribor, Slovenia,
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Randall-Demllo S, Chieppa M, Eri R. Intestinal epithelium and autophagy: partners in gut homeostasis. Front Immunol 2013; 4:301. [PMID: 24137160 PMCID: PMC3786390 DOI: 10.3389/fimmu.2013.00301] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 09/10/2013] [Indexed: 12/21/2022] Open
Abstract
One of the most significant challenges of cell biology is to understand how each type of cell copes with its specific workload without suffering damage. Among the most intriguing questions concerns intestinal epithelial cells in mammals; these cells act as a barrier between the internally protected region and the external environment that is exposed constantly to food and microbes. A major process involved in the processing of microbes is autophagy. In the intestine, through multiple, complex signaling pathways, autophagy including macroautophagy and xenophagy is pivotal in mounting appropriate intestinal immune responses and anti-microbial protection. Dysfunctional autophagy mechanism leads to chronic intestinal inflammation, such as inflammatory bowel disease (IBD). Studies involving a number of in vitro and in vivo mouse models in addition to human clinical studies have revealed a detailed role for autophagy in the generation of chronic intestinal inflammation. A number of genome-wide association studies identified roles for numerous autophagy genes in IBD, especially in Crohn’s disease. In this review, we will explore in detail the latest research linking autophagy to intestinal homeostasis and how alterations in autophagy pathways lead to intestinal inflammation.
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Affiliation(s)
- Sarron Randall-Demllo
- Mucosal Biology Laboratory, School of Human Life Sciences, University of Tasmania , Launceston, TAS , Australia
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15
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Nys K, Agostinis P, Vermeire S. Autophagy: a new target or an old strategy for the treatment of Crohn's disease? Nat Rev Gastroenterol Hepatol 2013; 10:395-401. [PMID: 23591407 DOI: 10.1038/nrgastro.2013.66] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In the past 5 years much progress has been made in understanding the molecular basis of Crohn's disease, a multifactorial chronic inflammatory disease of the gastrointestinal tract. Data suggest that hampered autophagy--the major lysosomal pathway for recycling of cytoplasmic material--might contribute to an increased susceptibility to Crohn's disease. Consequently, intense investigations have started to evaluate the potential value of autophagy as a therapeutic target and as a highly needed diagnostic tool. Interestingly, as well as the promising introduction of direct autophagic modulators, several drugs already used in the treatment of Crohn's disease might exert at least part of their effect through the regulation of autophagy. However, whether this phenomenon contributes to or rather counteracts their therapeutic use, remains to be determined and might prove to be highly compound-specific. Here we review the complex and emerging role of autophagy modulation in the battle against Crohn's disease. Moreover, we discuss the potential benefits and deleterious effects of autophagic regulation by both new and clinically used drugs.
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Affiliation(s)
- Kris Nys
- Translational Research in Gastrointestinal Disorders, Department of Clinical and Experimental Medicine, Faculty of Medicine, Catholic University of Leuven, Herestraat 49, Box 701, 3000 Leuven, Belgium
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Jiang T, Qin B, He J, Lin S, Ding S. Three isoforms of the Atg16L1 protein contribute different autophagic properties. Mol Cell Biochem 2013; 378:257-66. [PMID: 23512522 PMCID: PMC3634981 DOI: 10.1007/s11010-013-1616-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 03/02/2013] [Indexed: 12/11/2022]
Abstract
The mammalian Atg16L1 protein consists of a coiled-coil domain and a tryptophan-aspartic acid (WD) repeat domain and is involved in the process of autophagy. However, the mechanisms underlying the effect of the Atg16L1 isoforms on autophagy remain to be elucidated in humans. In the present study, we successfully cloned three isoforms: Atg16L1-1, which contains the complete sequence; Atg16L1-2, which lacks all of exon 8; and Atg16L1-3, which lacks the coiled-coil domain. Subsequent experiments showed that the three isoforms of Atg16L1 were colocalised with MDC within the cells. Quantitative analysis of fluorescence showed that the average number of dots of Atg16L1-1 that colocalised with MDC was higher than those of Atg16L1-2 and Atg16L1-3. The three isoforms of Atg16L1 also colocalised with the lysosome within the cells. The average number of dots of Atg16L1-1 that colocalised with the lysosome was higher than those of Atg16L1-2 and Atg16L1-3. However, although Atg16L1-1 and Atg16L1-3 colocalised with the mitochondria, Atg16L1-2 did not. Functional analysis showed that overexpression of the three isoforms of Atg16L1 had a stimulative effect on autophagy. Significant increase in the number of positive LC3-II dots per cell was observed in Atg16L1-1 (70.2 ± 2.39 dots); this number was greater than those of the other two isoforms. Atg16L1-2 appeared to have an average of 59.25 ± 2.22 LC3-II dots per cell. Atg16L1-3 appeared to have the least number of LC3-II dots per cell (48.25 ± 2.22 dots) (P < 0.001). Our results indicated that the degree of autophagy varied with different Atg16L1 isoforms. The different domains of Atg16L1 played different roles in the process of autophagy. The coiled-coil domain of Atg16L1 was involved in the process of autophagy.
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Affiliation(s)
- Tao Jiang
- The National Education Base for Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
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