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Yasuda T, Takagi T, Asaeda K, Hashimoto H, Kajiwara M, Azuma Y, Kitae H, Hirai Y, Mizushima K, Doi T, Inoue K, Dohi O, Yoshida N, Uchiyama K, Ishikawa T, Konishi H, Ukawa Y, Kohara A, Kudoh M, Inoue R, Naito Y, Itoh Y. Urolithin A-mediated augmentation of intestinal barrier function through elevated secretory mucin synthesis. Sci Rep 2024; 14:15706. [PMID: 38977770 PMCID: PMC11231190 DOI: 10.1038/s41598-024-65791-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Accepted: 06/24/2024] [Indexed: 07/10/2024] Open
Abstract
Maintaining the mucus layer is crucial for the innate immune system. Urolithin A (Uro A) is a gut microbiota-derived metabolite; however, its effect on mucin production as a physical barrier remains unclear. This study aimed to elucidate the protective effects of Uro A on mucin production in the colon. In vivo experiments employing wild-type mice, NF-E2-related factor 2 (Nrf2)-deficient mice, and wild-type mice treated with an aryl hydrocarbon receptor (AhR) antagonist were conducted to investigate the physiological role of Uro A. Additionally, in vitro assays using mucin-producing cells (LS174T) were conducted to assess mucus production following Uro A treatment. We found that Uro A thickened murine colonic mucus via enhanced mucin 2 expression facilitated by Nrf2 and AhR signaling without altering tight junctions. Uro A reduced mucosal permeability in fluorescein isothiocyanate-dextran experiments and alleviated dextran sulfate sodium-induced colitis. Uro A treatment increased short-chain fatty acid-producing bacteria and propionic acid concentration. LS174T cell studies confirmed that Uro A promotes mucus production through the AhR and Nrf2 pathways. In conclusion, the enhanced intestinal mucus secretion induced by Uro A is mediated through the actions of Nrf-2 and AhR, which help maintain intestinal barrier function.
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Affiliation(s)
- Takeshi Yasuda
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Tomohisa Takagi
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.
- Department for Medical Innovation and Translational Medical Science, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.
| | - Kohei Asaeda
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Hikaru Hashimoto
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Mariko Kajiwara
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yuka Azuma
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Hiroaki Kitae
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yasuko Hirai
- Department of Human Immunology and Nutrition Science, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Katsura Mizushima
- Department of Human Immunology and Nutrition Science, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Toshifumi Doi
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Ken Inoue
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Osamu Dohi
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Naohisa Yoshida
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Kazuhiko Uchiyama
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Takeshi Ishikawa
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Hideyuki Konishi
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yuichi Ukawa
- Daicel Corporation, Healthcare SBU, Tokyo, 108-8230, Japan
| | - Akiko Kohara
- Daicel Corporation, Healthcare SBU, Tokyo, 108-8230, Japan
| | - Masatake Kudoh
- Daicel Corporation, Healthcare SBU, Niigata, 944-8550, Japan
| | - Ryo Inoue
- Laboratory of Animal Science, Department of Applied Biological Sciences, Faculty of Agriculture, Setsunan University, Hirakata, 572-8508, Japan
| | - Yuji Naito
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
- Department of Human Immunology and Nutrition Science, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yoshito Itoh
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
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Kuo CH, Wu LL, Chen HP, Yu J, Wu CY. Direct effects of alcohol on gut-epithelial barrier: Unraveling the disruption of physical and chemical barrier of the gut-epithelial barrier that compromises the host-microbiota interface upon alcohol exposure. J Gastroenterol Hepatol 2024; 39:1247-1255. [PMID: 38509796 DOI: 10.1111/jgh.16539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 03/22/2024]
Abstract
The development of alcohol-associated diseases is multifactorial, mechanism of which involves metabolic alteration, dysregulated immune response, and a perturbed intestinal host-environment interface. Emerging evidence has pinpointed the critical role of the intestinal host-microbiota interaction in alcohol-induced injuries, suggesting its contribution to disease initiation and development. To maintain homeostasis in the gut, the intestinal mucosa serves as the first-line defense against exogenous factors in the gastrointestinal tract, including dietary contents and the commensal microbiota. The gut-epithelial barrier comprises a physical barrier lined with a single layer of intestinal epithelial cells and a chemical barrier with mucus trapping host regulatory factors and gut commensal bacteria. In this article, we review recent studies pertaining to the disrupted gut-epithelial barrier upon alcohol exposure and examine how alcohol and its metabolism can affect the regulatory ability of intestinal epithelium.
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Affiliation(s)
- Cheng-Hao Kuo
- School of Medicine, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Institute of Clinical Medicine, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Li-Ling Wu
- Institute of Physiology, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Health Innovation Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Microbiota Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Hsiao-Ping Chen
- Institute of Biomedical Informatics, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Division of Translational Research, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jun Yu
- Department of Medicine and Therapeutics, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong, China
| | - Chun-Ying Wu
- Institute of Clinical Medicine, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Health Innovation Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Microbiota Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Institute of Biomedical Informatics, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Division of Translational Research, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan
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3
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Zhang J, Wang H, Chen H, Liu Y, Wang A, Hou H, Hu Q. Acetaldehyde induces similar cytotoxic and genotoxic risks in BEAS-2B cells and HHSteCs: involvement of differential regulation of MAPK/ERK and PI3K/AKT pathways. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-27508-x. [PMID: 37284951 DOI: 10.1007/s11356-023-27508-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 05/04/2023] [Indexed: 06/08/2023]
Abstract
Long-term use of alcohol and cigarettes is associated with millions of deaths each year, directly or indirectly. The carcinogen acetaldehyde is both a metabolite of alcohol and the most abundant carbonyl compound in cigarette smoke, and co-exposure of them is usual and primarily leads to liver and lung injury, respectively. However, few studies have explored the synchronic risk of acetaldehyde on the liver and lung. Here, we investigated the toxic effects and related mechanisms of acetaldehyde based on normal hepatocytes and lung cells. The results showed that acetaldehyde caused significant dose-dependent increases of cytotoxicity, ROS level, DNA adduct level, DNA single/double-strand breakage, and chromosomal damage in BEAS-2B cells and HHSteCs, with similar effects at the same doses. The gene and protein expression and phosphorylation of p38MAPK, ERK, PI3K, and AKT, key proteins of MAPK/ERK and PI3K/AKT pathways regulating cell survival and tumorigenesis, were significantly upregulated on BEAS-2B cells, while only protein expression and phosphorylation of ERK were upregulated significantly, the other three decreased in HHSteCs. When either the inhibitor of the four key proteins was co-treated with acetaldehyde, cell viabilities were almost unchanged in BEAS-2B cells and HHSteCs. Thus, acetaldehyde could synchronically induce similar toxic effects in BEAS-2B cells and HHSteCs, and MAPK/ERK and PI3K/AKT pathways seem to be involved in different regulatory mechanisms.
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Affiliation(s)
- Jingni Zhang
- University of Science and Technology of China, 230026, Hefei, China
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, 450001, China
- Key Laboratory of Tobacco Biological Effects, Zhengzhou, 450001, China
- Beijing Life Science Academy, Beijing, 102200, China
- Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, 102200, China
| | - Hongjuan Wang
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, 450001, China
- Key Laboratory of Tobacco Biological Effects, Zhengzhou, 450001, China
- Beijing Life Science Academy, Beijing, 102200, China
- Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, 102200, China
| | - Huan Chen
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, 450001, China
- Key Laboratory of Tobacco Biological Effects, Zhengzhou, 450001, China
- Beijing Life Science Academy, Beijing, 102200, China
- Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, 102200, China
| | - Yong Liu
- University of Science and Technology of China, 230026, Hefei, China
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China
| | - An Wang
- University of Science and Technology of China, 230026, Hefei, China
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China
| | - Hongwei Hou
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, 450001, China
- Key Laboratory of Tobacco Biological Effects, Zhengzhou, 450001, China
- Beijing Life Science Academy, Beijing, 102200, China
- Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, 102200, China
| | - Qingyuan Hu
- University of Science and Technology of China, 230026, Hefei, China.
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, 450001, China.
- Key Laboratory of Tobacco Biological Effects, Zhengzhou, 450001, China.
- Beijing Life Science Academy, Beijing, 102200, China.
- Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, 102200, China.
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4
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Shih CC, Liao WC, Ke HY, Kuo CW, Tsao CM, Tsai WC, Chiu YL, Huang HC, Wu CC. Antimicrobial peptide cathelicidin LL-37 preserves intestinal barrier and organ function in rats with heat stroke. Biomed Pharmacother 2023; 161:114565. [PMID: 36958193 DOI: 10.1016/j.biopha.2023.114565] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/14/2023] [Accepted: 03/16/2023] [Indexed: 03/25/2023] Open
Abstract
Global warming increases the incidence of heat stroke (HS) and HS causes the reduction of visceral blood flow during hyperthermia, leading to intestinal barrier disruption, microbial translocation, systemic inflammation and multiple organ failure. Cathelicidin LL-37 exhibits antimicrobial activities, helps innate immunity within the gut to maintain intestinal homeostasis, and augments intestinal wound healing and barrier function. Thus, we evaluated the effects and possible mechanisms of cathelicidin LL-37 on HS. Wistar rats were placed in a heating-chamber of 42 ̊C to induce HS. Changes in rectal temperature, hemodynamic parameters, and survival rate were measured during the experimental period. Blood samples and ilea were collected to analyze the effects of LL-37 on systemic inflammation, multiple organ dysfunction, and intestinal injury. Furthermore, LS174T and HT-29 cells were used to assess the underlying mechanisms. Our data showed cathelicidin LL-37 ameliorated the damage of intestinal cells induced by HS. Intestinal injury, systemic inflammation, and nitrosative stress (high nitric oxide level) caused by continuous hyperthermia were attenuated in HS rats treated with cathelicidin LL-37, and hence, improved multiple organ dysfunction, coagulopathy, and survival rate. These beneficial effects of cathelicidin LL-37 were attributed to the protection of intestinal goblet cells (by increasing transepithelial resistance, mucin-2 and Nrf2 expression) and the improvement of intestinal barrier function (less cyclooxygenase-2 expression and FITC-dextran translocation). Interestingly, high cathelicidin expression in the ileal samples of inflammatory bowel disease patients was associated with better clinical outcome. These results suggest that cathelicidin LL-37 could prevent heat stress-induced intestinal damage and heat-related illnesses.
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Affiliation(s)
- Chih-Chin Shih
- Department and Graduate Institute of Pharmacology, National Defense Medical Center, Taipei, Taiwan, ROC.
| | - Wei-Chieh Liao
- Department and Graduate Institute of Pharmacology, National Defense Medical Center, Taipei, Taiwan, ROC
| | - Hung-Yen Ke
- Division of Cardiovascular Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC
| | - Chia-Wen Kuo
- Department of Nephrology, Taichung Armed Forces General Hospital, Taichung, Taiwan, ROC
| | - Cheng-Ming Tsao
- Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming Chiao-Tung University, Taipei, Taiwan, ROC
| | - Wen-Chiuan Tsai
- Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC
| | - Yi-Lin Chiu
- Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan, ROC
| | - Hsieh-Chou Huang
- Department of Anesthesiology, Cheng-Hsin General Hospital, Taipei, Taiwan, ROC
| | - Chin-Chen Wu
- Department and Graduate Institute of Pharmacology, National Defense Medical Center, Taipei, Taiwan, ROC.
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5
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Hii HP, Lo WZ, Fu YH, Chen MH, Shih CC, Tsao CM, Ka SM, Chiu YL, Wu CC, Shih CC. Improvement in heat stress-induced multiple organ dysfunction and intestinal damage through protection of intestinal goblet cells from prostaglandin E1 analogue misoprostol. Life Sci 2022; 310:121039. [DOI: 10.1016/j.lfs.2022.121039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 09/23/2022] [Accepted: 10/01/2022] [Indexed: 11/09/2022]
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6
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Host-microbiome interactions: Gut-Liver axis and its connection with other organs. NPJ Biofilms Microbiomes 2022; 8:89. [PMID: 36319663 PMCID: PMC9626460 DOI: 10.1038/s41522-022-00352-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/18/2022] [Indexed: 11/26/2022] Open
Abstract
An understanding of connections between gut microbiome and liver has provided important insights into the pathophysiology of liver diseases. Since gut microbial dysbiosis increases gut permeability, the metabolites biosynthesized by them can reach the liver through portal circulation and affect hepatic immunity and inflammation. The immune cells activated by these metabolites can also reach liver through lymphatic circulation. Liver influences immunity and metabolism in multiple organs in the body, including gut. It releases bile acids and other metabolites into biliary tract from where they enter the systemic circulation. In this review, the bidirectional communication between the gut and the liver and the molecular cross talk between the host and the microbiome has been discussed. This review also provides details into the intricate level of communication and the role of microbiome in Gut-Liver-Brain, Gut-Liver-Kidney, Gut-Liver-Lung, and Gut-Liver-Heart axes. These observations indicate a complex network of interactions between host organs influenced by gut microbiome.
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7
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Ma F, Huo Y, Li H, Yang F, Liao J, Han Q, Li Y, Pan J, Hu L, Guo J, Tang Z. New insights into the interaction between duodenal toxicity and microbiota disorder under copper exposure in chicken: Involving in endoplasmic reticulum stress and mitochondrial toxicity. Chem Biol Interact 2022; 366:110132. [PMID: 36030842 DOI: 10.1016/j.cbi.2022.110132] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/18/2022] [Accepted: 08/21/2022] [Indexed: 12/17/2022]
Abstract
Copper (Cu) has been widely used in industrial agricultural production, but excess use can lead to toxic effect on host physiology, which poses a threaten to public hygiene. However, the relationship between gut microbiota and Cu-induced intestinal toxicity is unclear. Here, we identified that intestinal flora disturbance was related to duodenal toxicity under Cu exposure. We found that excess Cu disturbed gut microbiota homeostasis, resulting in Cu accumulation and intestinal damage. In addition, Cu considerably increased intestinal permeability by reducing expression of tight junction proteins (Claudlin-1, Occludin, and ZO-1). Meanwhile, Cu could induce endoplasmic reticulum stress, mitophagy, and mitochondria-mediated apoptosis in the duodenum, with the evidence by the elevated levels of GRP78, GRP94, LC3Ⅱ/LC3Ⅰ and Caspase-3 protein expression. Correlation analysis showed that Melainabacteria was closely related to tight junction proteins and endoplasmic reticulum stress of duodenum, indicating that disturbance of intestinal flora may aggravate the toxic effect of Cu. Therefore, our results suggest that the destruction of intestinal flora induced by excessive Cu may further lead to intestinal barrier damage, ultimately leading to endoplasmic reticulum stress, mitophagy and apoptosis. This research provides a new insight into interpretation of the interrelationship between microbiota disorder and duodenal toxicity under Cu exposure.
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Affiliation(s)
- Feiyang Ma
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Yihui Huo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Huayu Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Fan Yang
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, 330045, China.
| | - Jianzhao Liao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Qingyue Han
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Ying Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Jiaqiang Pan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Lianmei Hu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Jianying Guo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Zhaoxin Tang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
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8
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Eisenbrand G, Baum M, Cartus AT, Diel P, Engel KH, Engeli B, Epe B, Grune T, Guth S, Haller D, Heinz V, Hellwig M, Hengstler JG, Henle T, Humpf HU, Jäger H, Joost HG, Kulling S, Lachenmeier DW, Lampen A, Leist M, Mally A, Marko D, Nöthlings U, Röhrdanz E, Roth A, Spranger J, Stadler R, Vieths S, Wätjen W, Steinberg P. Salivary nitrate/nitrite and acetaldehyde in humans: potential combination effects in the upper gastrointestinal tract and possible consequences for the in vivo formation of N-nitroso compounds-a hypothesis. Arch Toxicol 2022; 96:1905-1914. [PMID: 35504979 DOI: 10.1007/s00204-022-03296-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 03/24/2022] [Indexed: 11/28/2022]
Abstract
Subsequent to the dietary uptake of nitrate/nitrite in combination with acetaldehyde/ethanol, combination effects resulting from the sustained endogenous exposure to nitrite and acetaldehyde may be expected. This may imply locoregional effects in the upper gastrointestinal tract as well as systemic effects, such as a potential influence on endogenous formation of N-nitroso compounds (NOC). Salivary concentrations of the individual components nitrate and nitrite and acetaldehyde are known to rise after ingestion, absorption and systemic distribution, thereby reflecting their respective plasma kinetics and parallel secretion through the salivary glands as well as the microbial/enzymatic metabolism in the oral cavity. Salivary excretion may also occur with certain drug molecules and food constituents and their metabolites. Therefore, putative combination effects in the oral cavity and the upper digestive tract may occur, but this has remained largely unexplored up to now. In this Guest Editorial, published evidence on exposure levels and biokinetics of nitrate/nitrite/NOx, NOC and acetaldehyde in the organism is reviewed and knowledge gaps concerning combination effects are identified. Research is suggested to be initiated to study the related unresolved issues.
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Affiliation(s)
| | - Matthias Baum
- Solenis Germany Industries GmbH, Fütingsweg 20, 47805, Krefeld, Germany
| | | | - Patrick Diel
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany
| | - Karl-Heinz Engel
- Chair of General Food Technology, Technical University of Munich, Maximus-von-Imhof-Forum 2, 85354, Freising, Germany
| | - Barbara Engeli
- Risk Assessment Division, Federal Food Safety and Veterinary Office (FSVO), Schwarzenburgstrasse 155, 3003, Bern, Switzerland
| | - Bernd Epe
- Institute of Pharmaceutical and Biomedical Sciences, University of Mainz, Staudinger Weg 5, 55128, Mainz, Germany
| | - Tilman Grune
- Department of Molecular Toxicology, German Institute of Human Nutrition (DIfE), Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Sabine Guth
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystr. 67, 44139, Dortmund, Germany
| | - Dirk Haller
- ZIEL, Institute for Food and Health, Technical University of Munich, 85354, Freising, Germany.,Chair of Nutrition and Immunology, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany
| | - Volker Heinz
- German Institute of Food Technologies (DIL), Prof.-von-Klitzing-Str. 7, 49610, Quakenbrück, Germany
| | - Michael Hellwig
- Institute of Food Chemistry, Technical University of Braunschweig, Schleinitzstr. 20, 38106, Braunschweig, Germany
| | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystr. 67, 44139, Dortmund, Germany
| | - Thomas Henle
- Department of Food Chemistry, TU Dresden, Bergstrasse 66, 01069, Dresden, Germany
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, Westfälische Wilhelms-Universität Münster, Corrensstraße 45, 48149, Münster, Germany
| | - Henry Jäger
- Institute of Food Technology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Hans-Georg Joost
- Department of Experimental Diabetology, German Institute of Human Nutrition (DIfE), Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Sabine Kulling
- Department of Safety and Quality of Fruit and Vegetables, Federal Research Institute of Nutrition and Food, Max Rubner-Institut, Haid-und-Neu-Straße 9, 76131, Karlsruhe, Germany
| | - Dirk W Lachenmeier
- Chemisches und Veterinäruntersuchungsamt Karlsruhe, Weißenburger Straße 3, 76187, Karlsruhe, Germany
| | - Alfonso Lampen
- Risk Assessment Strategies, Bundesinstitut für Risikobewertung (BfR), Max-Dohrn-Straße 8-10, Berlin, Germany
| | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Box 657, 78457, Konstanz, Germany
| | - Angela Mally
- Department of Toxicology, University of Würzburg, Versbacher Str. 9, 97078, Würzburg, Germany
| | - Doris Marko
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria
| | - Ute Nöthlings
- Department of Nutrition and Food Sciences, Nutritional Epidemiology, Rheinische Friedrich-Wilhelms University Bonn, Friedrich-Hirzebruch-Allee 7, 53115, Bonn, Germany
| | - Elke Röhrdanz
- Unit Reproductive and Genetic Toxicology, Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger Allee 3, 53175, Bonn, Germany
| | - Angelika Roth
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystr. 67, 44139, Dortmund, Germany
| | - Joachim Spranger
- Department of Endocrinology and Metabolic Medicine, Campus Benjamin Franklin, Charité University Medicine, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Richard Stadler
- Institute of Food Safety and Analytic Sciences, Nestlé Research Centre, Route du Jorat 57, 1000, Lausanne 26, Switzerland
| | - Stefan Vieths
- Federal Institute for Vaccines and Biomedicines, Paul-Ehrlich-Institut, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany
| | - Wim Wätjen
- Institut für Agrar- und Ernährungswissenschaften, Martin-Luther-Universität Halle-Wittenberg, Weinbergweg 22, 06120, Halle (Saale), Germany
| | - Pablo Steinberg
- Federal Research Institute of Nutrition and Food, Max Rubner-Institut, Haid-und-Neu-Straße 9, 76131, Karlsruhe, Germany.
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9
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Xiang H, Sun D, Liu X, She ZG, Chen Y. The Role of the Intestinal Microbiota in Nonalcoholic Steatohepatitis. Front Endocrinol (Lausanne) 2022; 13:812610. [PMID: 35211093 PMCID: PMC8861316 DOI: 10.3389/fendo.2022.812610] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/04/2022] [Indexed: 12/12/2022] Open
Abstract
Nonalcoholic steatohepatitis (NASH) is a serious disease threatening public health, and its pathogenesis remains largely unclear. Recent scientific research has shown that intestinal microbiota and its metabolites have an important impact on the development of NASH. A balanced intestinal microbiota contributes to the maintenance of liver homeostasis, but when the intestinal microbiota is disequilibrated, it serves as a source of pathogens and molecules that lead to NASH. In this review, we mainly emphasize the key mechanisms by which the intestinal microbiota and its metabolites affect NASH. In addition, recent clinical trials and animal studies on the treatment of NASH by regulating the intestinal microbiota through prebiotics, probiotics, synbiotics and FMT have also been briefly elaborated. With the increasing understanding of interactions between the intestinal microbiota and liver, accurate and personalized detection and treatment methods for NASH are expected to be established.
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Affiliation(s)
- Hui Xiang
- Infectious Disease Department, Chongqing University Three Gorges Hospital, Chongqing, China
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
- *Correspondence: Hui Xiang, ; Zhi-Gang She, ; Yonghong Chen,
| | - Dating Sun
- Department of Cardiology, Wuhan NO.1 Hospital, Wuhan, China
| | - Xin Liu
- Infectious Disease Department, Chongqing University Three Gorges Hospital, Chongqing, China
| | - Zhi-Gang She
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
- *Correspondence: Hui Xiang, ; Zhi-Gang She, ; Yonghong Chen,
| | - Yonghong Chen
- Infectious Disease Department, Chongqing University Three Gorges Hospital, Chongqing, China
- *Correspondence: Hui Xiang, ; Zhi-Gang She, ; Yonghong Chen,
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10
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Lin LW, Denison MS, Rice RH. Woodsmoke Extracts Cross-Link Proteins and Induce Cornified Envelope Formation without Stimulating Keratinocyte Terminal Differentiation. Toxicol Sci 2021; 183:128-138. [PMID: 34086961 PMCID: PMC8502463 DOI: 10.1093/toxsci/kfab071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Air pollution poses a serious risk to human health. To help understand the contribution of smoke from wood burning to the harmfulness of air pollution toward the skin, we studied the effects of liquid smoke, aqueous extracts of wood smoke condensate, a commercially available food flavor additive, in cultured keratinocytes. We report that liquid smoke can react with and cross-link keratinocyte cellular proteins, leading to abnormal cross-linked envelope formation. Instead of inducing genes ordinarily involved in terminal differentiation, liquid smoke induced expression of genes associated with stress responses. When transglutaminase activity was inhibited, liquid smoke still promoted protein cross-linking and envelope formation in keratinocytes. This phenomenon likely results from oxidative stress and protein adducts from aldehydes as either preloading the cells with N-acetylcysteine or reducing the aldehyde content of liquid smoke decreased its ability to promote protein cross-linking and envelope formation. Finally, liquid smoke-induced envelopes were found to have elevated protein content, suggesting oxidative cross-linking and formation of protein adducts might impair barrier function by inducing abnormal incorporation of cellular proteins into envelopes. Since the cross-linked protein envelope provides structural stability to the stratum corneum and serves as a scaffold for the organization of the corneocyte lipid envelope (hydrophobic barrier to the environment), these findings provide new insight into the mechanism by which pro-oxidative air pollutants can impair epidermal function.
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Affiliation(s)
- Lo-Wei Lin
- Department of Environmental Toxicology, University of California, Davis, CA 95616-8588, USA
| | | | - Robert H Rice
- Department of Environmental Toxicology, University of California, Davis, CA 95616-8588, USA
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11
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Ude VC, Brown DM, Stone V, Johnston HJ. Time dependent impact of copper oxide nanomaterials on the expression of genes associated with oxidative stress, metal binding, inflammation and mucus secretion in single and co-culture intestinal in vitro models. Toxicol In Vitro 2021; 74:105161. [PMID: 33839236 DOI: 10.1016/j.tiv.2021.105161] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 03/05/2021] [Accepted: 04/04/2021] [Indexed: 12/18/2022]
Abstract
The potential for ingestion of copper oxide nanomaterials (CuO NMs) is increasing due to their increased exploitation. Investigation of changes in gene expression allows toxicity to be detected at an early stage of NM exposure and can enable investigation of the mechanism of toxicity. Here, undifferentiated Caco-2 cells, differentiated Caco-2 cells, Caco-2/HT29-MTX (mucus secreting) and Caco-2/Raji B (M cell model) co-cultures were exposed to CuO NMs and copper sulphate (CuSO4) in order to determine their impacts. Cellular responses were measured in terms of production of reactive oxygen species (ROS), the gene expression of an antioxidant (haem oxygenase 1 (HMOX1)), the pro-inflammatory cytokine (interleukin 8 (IL8)), the metal binding (metallothionein 1A and 2A (MT1A and MT2A)) and the mucus secreting (mucin 2 (MUC2)), as well as HMOX-1 protein level. While CuSO4 induced ROS production in cells, no such effect was observed for CuO NMs. However, these particles did induce an increase in the level of HMOX-1 protein and upregulation of HMOX1, MT2A, IL8 and MUC2 genes in all cell models. In conclusion, the expression of HMOX1, IL8 and MT2A were responsive to CuO NMs at 4 to 12 h post exposure when investigating the toxicity of NMs using intestinal in vitro models. These findings can inform the selection of endpoints, timepoints and models when investigating NM toxicity to the intestine in vitro in the future.
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Affiliation(s)
- Victor C Ude
- Nano Safety Research Group, School of Engineering and Physical Sciences, Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK.
| | - David M Brown
- Nano Safety Research Group, School of Engineering and Physical Sciences, Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK.
| | - Vicki Stone
- Nano Safety Research Group, School of Engineering and Physical Sciences, Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK.
| | - Helinor J Johnston
- Nano Safety Research Group, School of Engineering and Physical Sciences, Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK.
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12
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Translational Approaches with Antioxidant Phytochemicals against Alcohol-Mediated Oxidative Stress, Gut Dysbiosis, Intestinal Barrier Dysfunction, and Fatty Liver Disease. Antioxidants (Basel) 2021; 10:antiox10030384. [PMID: 33806556 PMCID: PMC8000766 DOI: 10.3390/antiox10030384] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/25/2021] [Accepted: 02/25/2021] [Indexed: 12/12/2022] Open
Abstract
Emerging data demonstrate the important roles of altered gut microbiomes (dysbiosis) in many disease states in the peripheral tissues and the central nervous system. Gut dysbiosis with decreased ratios of Bacteroidetes/Firmicutes and other changes are reported to be caused by many disease states and various environmental factors, such as ethanol (e.g., alcohol drinking), Western-style high-fat diets, high fructose, etc. It is also caused by genetic factors, including genetic polymorphisms and epigenetic changes in different individuals. Gut dysbiosis, impaired intestinal barrier function, and elevated serum endotoxin levels can be observed in human patients and/or experimental rodent models exposed to these factors or with certain disease states. However, gut dysbiosis and leaky gut can be normalized through lifestyle alterations such as increased consumption of healthy diets with various fruits and vegetables containing many different kinds of antioxidant phytochemicals. In this review, we describe the mechanisms of gut dysbiosis, leaky gut, endotoxemia, and fatty liver disease with a specific focus on the alcohol-associated pathways. We also mention translational approaches by discussing the benefits of many antioxidant phytochemicals and/or their metabolites against alcohol-mediated oxidative stress, gut dysbiosis, intestinal barrier dysfunction, and fatty liver disease.
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13
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Yu SY, Xu L. The interplay between host cellular and gut microbial metabolism in NAFLD development and prevention. J Appl Microbiol 2021; 131:564-582. [PMID: 33411984 DOI: 10.1111/jam.14992] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/27/2020] [Accepted: 01/04/2021] [Indexed: 12/12/2022]
Abstract
Metabolism regulation centred on insulin resistance is increasingly important in nonalcoholic fatty liver disease (NAFLD). This review focuses on the interactions between the host cellular and gut microbial metabolism during the development of NAFLD. The cellular metabolism of essential nutrients, such as glucose, lipids and amino acids, is reconstructed with inflammation, immune mechanisms and oxidative stress, and these alterations modify the intestinal, hepatic and systemic environments, and regulate the composition and activity of gut microbes. Microbial metabolites, such as short-chain fatty acids, secondary bile acids, protein fermentation products, choline and ethanol and bacterial toxicants, such as lipopolysaccharides, peptidoglycans and bacterial DNA, play vital roles in NAFLD. The microbe-metabolite relationship is crucial for the modulation of intestinal microbial composition and metabolic activity. The intestinal microbiota and their metabolites participate in epithelial cell metabolism via a series of cell receptors and signalling pathways and remodel the metabolism of various cells in the liver via the gut-liver axis. Microbial metabolic manipulation is a promising strategy for NAFLD prevention, but larger-sampled clinical trials are required for future application.
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Affiliation(s)
- S-Y Yu
- Department of Gastroenterology, Ningbo First Hospital, Ningbo, China
| | - L Xu
- Department of Gastroenterology, Ningbo First Hospital, Ningbo, China
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14
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Bruellman R, Llorente C. A Perspective Of Intestinal Immune-Microbiome Interactions In Alcohol-Associated Liver Disease. Int J Biol Sci 2021; 17:307-327. [PMID: 33390852 PMCID: PMC7757023 DOI: 10.7150/ijbs.53589] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023] Open
Abstract
Uncovering the intricacies of the gut microbiome and how it interacts with the host immune system has opened up pathways in the search for the treatment of disease conditions. Alcohol-associated liver disease is a major cause of death worldwide. Research has shed light on the breakdown of the protective gut barriers, translocation of gut microbes to the liver and inflammatory immune response to microbes all contributing to alcohol-associated liver disease. This knowledge has opened up avenues for alternative therapies to alleviate alcohol-associated liver disease based on the interaction of the commensal gut microbiome as a key player in the regulation of the immune response. This review describes the relevance of the intestinal immune system, the gut microbiota, and specialized and non-specialized intestinal cells in the regulation of intestinal homeostasis. It also reflects how these components are altered during alcohol-associated liver disease and discusses new approaches for potential future therapies in alcohol-associated liver disease.
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Affiliation(s)
- Ryan Bruellman
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Cristina Llorente
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
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15
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Amer A, Whelan A, Al-Hebshi NN, Healy CM, Moran GP. Acetaldehyde production by Rothia mucilaginosa isolates from patients with oral leukoplakia. J Oral Microbiol 2020; 12:1743066. [PMID: 32341761 PMCID: PMC7170386 DOI: 10.1080/20002297.2020.1743066] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/16/2020] [Accepted: 02/20/2020] [Indexed: 11/23/2022] Open
Abstract
Rothia mucilaginosa has been found at high abundance on oral leukoplakia (OLK). The ability of clinical isolates to produce acetaldehyde (ACH) from ethanol has not been investigated. The objective of the current study was to determine the capacity of R. mucilaginosa isolates recovered from OLK to generate ACH. Analysis of R. mucilaginosa genomes (n = 70) shows that this species does not normally encode acetaldehyde dehydrogenase (ALDH) required for detoxification of ACH. The predicted OLK metagenome also exhibited reduced ALDH coding capacity. We analysed ACH production in 8 isolates of R. mucilaginosa and showed that this species is capable of generating ACH in the presence of ethanol. The levels of ACH produced (mean = 53 µM) were comparable to those produced by Neisseria mucosa and Candida albicans in parallel assays. These levels were demonstrated to induce oxidative stress in cultured oral keratinocytes. This study shows that R. mucilaginosa can generate ACH from ethanol in vitro at levels which can induce oxidative stress. This organism likely contributes to oral ACH levels following alcohol consumption and the significance of the increased abundance of R. mucilaginosa in patients with potentially malignant disorders requires further investigation.
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Affiliation(s)
- Abdrazak Amer
- Division of Oral Biosciences, School of Dental Science, Trinity College Dublin, Dublin Dental University Hospital, Dublin, Ireland
- Department of Genetic Engineering, Biotechnology Research Center (BTRC), Tripoli, Libya
| | - Aine Whelan
- School of Chemical and Pharmaceutical Sciences, Technological University, Dublin, Ireland
| | - Nezar N. Al-Hebshi
- Oral Microbiome Research Laboratory, Maurice H. Kornberg School of Dentistry, Temple University, Philadelphia, PA, USA
| | - Claire M. Healy
- Division of Oral and Maxillofacial Surgery, Oral Medicine and Oral Pathology, School of Dental Science, Trinity College Dublin, Dublin Dental University Hospital, Dublin, Ireland
| | - Gary P. Moran
- Division of Oral Biosciences, School of Dental Science, Trinity College Dublin, Dublin Dental University Hospital, Dublin, Ireland
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16
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Role of Probiotics in Non-alcoholic Fatty Liver Disease: Does Gut Microbiota Matter? Nutrients 2019; 11:nu11112837. [PMID: 31752378 PMCID: PMC6893593 DOI: 10.3390/nu11112837] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 12/20/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the hepatic consequence of metabolic syndrome, which often also includes obesity, diabetes, and dyslipidemia. The connection between gut microbiota (GM) and NAFLD has attracted significant attention in recent years. Data has shown that GM affects hepatic lipid metabolism and influences the balance between pro/anti-inflammatory effectors in the liver. Although studies reveal the association between GM dysbiosis and NAFLD, decoding the mechanisms of gut dysbiosis resulting in NAFLD remains challenging. The potential pathophysiology that links GM dysbiosis to NAFLD can be summarized as: (1) disrupting the balance between energy harvest and expenditure, (2) promoting hepatic inflammation (impairing intestinal integrity, facilitating endotoxemia, and initiating inflammatory cascades with cytokines releasing), and (3) altered biochemistry metabolism and GM-related metabolites (i.e., bile acid, short-chain fatty acids, aromatic amino acid derivatives, branched-chain amino acids, choline, ethanol). Due to the hypothesis that probiotics/synbiotics could normalize GM and reverse dysbiosis, there have been efforts to investigate the therapeutic effect of probiotics/synbiotics in patients with NAFLD. Recent randomized clinical trials suggest that probiotics/synbiotics could improve transaminases, hepatic steatosis, and reduce hepatic inflammation. Despite these promising results, future studies are necessary to understand the full role GM plays in NAFLD development and progression. Additionally, further data is needed to unravel probiotics/synbiotics efficacy, safety, and sustainability as a novel pharmacologic approaches to NAFLD.
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17
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Yu S, Zhang L, Liu C, Yang J, Zhang J, Huang L. PACS2 is required for ox-LDL-induced endothelial cell apoptosis by regulating mitochondria-associated ER membrane formation and mitochondrial Ca 2+ elevation. Exp Cell Res 2019; 379:191-202. [PMID: 30970236 DOI: 10.1016/j.yexcr.2019.04.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 04/01/2019] [Accepted: 04/03/2019] [Indexed: 01/01/2023]
Abstract
Oxidized low-density lipoprotein (ox-LDL)-induced endothelial cell (EC) apoptosis is the initial step of atherogenesis and associated with Ca2+ overload. Mitochondria-associated endoplasmic reticulum (ER) membrane (MAM), regulated by tethering proteins such as phosphofurin acidic cluster sorting protein 2 (PACS2), is essential for mitochondrial Ca2+ overload by mediating ER-mitochondria Ca2+ transfer. In our study, we aimed to investigate the role of PACS2 in ox-LDL-induced apoptosis in human umbilical vein endothelial cells (HUVECs) and the underlying mechanisms. Ox-LDL dose- and time-dependently increased cell apoptosis concomitant with mitochondrial Ca2+ elevation, mitochondrial membrane potential (MMP) loss, reactive oxygen species (ROS) production, and cytochrome c release. Silencing PACS2 significantly inhibited ox-LDL-induced cell apoptosis at 24 h in addition to the effects of ox-LDL on mitochondrial Ca2+, MMP, and ROS at 2 h. Besides, ox-LDL promoted PACS2 localization at mitochondria as well as ER-mitochondria contacts at 2 h. Not only that, ox-LDL upregulated PACS2 expression at 24 h. Furthermore, silencing PACS2 inhibited ox-LDL-induced mitochondrial localization of PACS2 and MAM formation at 24 h. Altogether, our findings suggest that PACS2 plays an important role in ox-LDL-induced EC apoptosis by regulating MAM formation and mitochondrial Ca2+ elevation, implicating that PACS2 may be a promising therapeutic target for atherosclerosis.
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Affiliation(s)
- Sanjiu Yu
- Institute of Cardiovascular Diseases, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
| | - Laiping Zhang
- Institute of Cardiovascular Diseases, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
| | - Chuan Liu
- Institute of Cardiovascular Diseases, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
| | - Jie Yang
- Institute of Cardiovascular Diseases, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
| | - Jihang Zhang
- Institute of Cardiovascular Diseases, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
| | - Lan Huang
- Institute of Cardiovascular Diseases, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
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18
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Perumpail BJ, Li AA, John N, Sallam S, Shah ND, Kwong W, Cholankeril G, Kim D, Ahmed A. The Therapeutic Implications of the Gut Microbiome and Probiotics in Patients with NAFLD. Diseases 2019; 7:diseases7010027. [PMID: 30823570 PMCID: PMC6473757 DOI: 10.3390/diseases7010027] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 02/21/2019] [Accepted: 02/24/2019] [Indexed: 02/07/2023] Open
Abstract
Recent breakthrough in our understanding pertaining to the pathogenesis of nonalcoholic fatty liver disease (NAFLD) has pointed to dysregulation or derangement of the gut microbiome, also known as dysbiosis. This has led to growing interest in probiotic supplementation as a potential treatment method for NAFLD due to its ability to retard and/or reverse dysbiosis and restore normal gut flora. A thorough review of medical literature was completed from inception through July 10, 2018 on the PubMed database by searching for key terms such as NAFLD, probiotics, dysbiosis, synbiotics, and nonalcoholic steatohepatitis (NASH). All studies reviewed indicate that probiotics had a beneficial effect in patients with NAFLD and its subset NASH. Results varied between studies, but there was evidence demonstrating improvement in liver enzymes, hepatic inflammation, hepatic steatosis, and hepatic fibrosis. No major adverse effects were noted. Currently, there are no guidelines addressing the use of probiotics in the setting of NAFLD. In conclusion, probiotics appear to be a promising option in the treatment of NAFLD. Future research is necessary to assess the efficacy of probiotics in patients with NAFLD.
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Affiliation(s)
| | - Andrew A Li
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Nimy John
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Sandy Sallam
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Neha D Shah
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Waiyee Kwong
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - George Cholankeril
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Donghee Kim
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Aijaz Ahmed
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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19
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Chu H, Duan Y, Yang L, Schnabl B. Small metabolites, possible big changes: a microbiota-centered view of non-alcoholic fatty liver disease. Gut 2019; 68:359-370. [PMID: 30171065 DOI: 10.1136/gutjnl-2018-316307] [Citation(s) in RCA: 195] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/02/2018] [Accepted: 08/06/2018] [Indexed: 12/13/2022]
Abstract
The spectrum of non-alcoholic fatty liver disease (NAFLD) ranges from simple hepatic steatosis, commonly associated with obesity, to non-alcoholic steatohepatitis, which can progress to fibrosis, cirrhosis and hepatocellular carcinoma. NAFLD pathophysiology involves environmental, genetic and metabolic factors, as well as changes in the intestinal microbiota and their products. Dysfunction of the intestinal barrier can contribute to NAFLD development and progression. Although there are technical limitations in assessing intestinal permeability in humans and the number of patients in these studies is rather small, fewer than half of the patients have increased intestinal permeability and translocation of bacterial products. Microbe-derived metabolites and the signalling pathways they affect might play more important roles in development of NAFLD. We review the microbial metabolites that contribute to the development of NAFLD, such as trimethylamine, bile acids, short-chain fatty acids and ethanol. We discuss the mechanisms by which metabolites produced by microbes might affect disease progression and/or serve as therapeutic targets or biomarkers for NAFLD.
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Affiliation(s)
- Huikuan Chu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Medicine, University of California San Diego, San Diego, California, USA
| | - Yi Duan
- Department of Medicine, University of California San Diego, San Diego, California, USA.,Department of Medicine, VA San Diego Healthcare System, San Diego, California, USA
| | - Ling Yang
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bernd Schnabl
- Department of Medicine, University of California San Diego, San Diego, California, USA.,Department of Medicine, VA San Diego Healthcare System, San Diego, California, USA
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20
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Acetaldehyde Induces Neurotoxicity In Vitro via Oxidative Stress- and Ca 2+ Imbalance-Mediated Endoplasmic Reticulum Stress. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:2593742. [PMID: 30728884 PMCID: PMC6343137 DOI: 10.1155/2019/2593742] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 11/13/2018] [Indexed: 01/24/2023]
Abstract
Excessive drinking can damage brain tissue and cause cognitive dysfunction. Studies have found that the early stage of neurodegenerative disease is closely related to heavy drinking. Acetaldehyde (ADE) is the main toxic metabolite of alcohol. However, the exact mechanisms of ADE-induced neurotoxicity are not fully clear. In this article, we studied the cytotoxic effect of ADE in HT22 cells and primary cultured cortical neuronal cells. We found that ADE exhibited cytotoxicities against HT22 cells and primary cultured cortical neuronal cells in dose-dependent manners. Furthermore, ADE induced apoptosis of HT22 cells by upregulating the expression of caspase family proapoptotic proteins. Moreover, ADE treatment could significantly increase the intracellular Ca2+ and reactive oxygen species (ROS) levels and activate endoplasmic reticulum stress (ERS) in HT22 cells. ADE upregulated ERS-related CHOP expression dose-dependently in primary cultured cortical neuronal cells. In addition, inhibition of ROS with antioxidant N-acetyl-L-cysteine (NAC) reduced the accumulation of ROS and reversed ADE-induced increase of ERS-related protein and apoptosis-related protein levels. Mitigation of ERS with ERS inhibitor 4-PBA obviously suppressed ADE-induced apoptosis and the expression of ERS-related proteins. Therefore, ADE induces neurotoxicity of HT22 cells via oxidative stress- and Ca2+ imbalance-mediated ERS.
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21
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Gut Microbiota-Derived Mediators as Potential Markers in Nonalcoholic Fatty Liver Disease. BIOMED RESEARCH INTERNATIONAL 2019; 2019:8507583. [PMID: 30719448 PMCID: PMC6334327 DOI: 10.1155/2019/8507583] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/20/2018] [Indexed: 12/17/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common, multifactorial, and poorly understood liver disease whose incidence is globally rising. During the past decade, several lines of evidence suggest that dysbiosis of intestinal microbiome represents an important factor contributing to NAFLD occurrence and its progression into NASH. The mechanisms that associate dysbiosis with NAFLD include changes in microbiota-derived mediators, deregulation of the gut endothelial barrier, translocation of mediators of dysbiosis, and hepatic inflammation. Changes in short chain fatty acids, bile acids, bacterial components, choline, and ethanol are the result of altered intestinal microbiota. We perform a narrative review of the previously published evidence and discuss the use of gut microbiota-derived mediators as potential markers in NAFLD.
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22
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Huang SJ, Xu YM, Lau ATY. Electronic cigarette: A recent update of its toxic effects on humans. J Cell Physiol 2018; 233:4466-4478. [PMID: 29215738 DOI: 10.1002/jcp.26352] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 11/29/2017] [Indexed: 02/05/2023]
Abstract
Electronic cigarettes (e-cigarettes), battery-powered and liquid-vaporizing devices, were invented to replace the conventional cigarette (c-cigarette) smoking for the sake of reducing the adverse effects on multiple organ systems that c-cigarettes have induced. Although some of the identified harmful components in e-cigarettes were alleged to be measured in lower quantity than those in c-cigarettes, researchers unveiled that the toxic effects of e-cigarettes should not be understated. This review is sought for an attempt to throw light on several typical types of e-cigarette components (tobacco-specific nitrosamines, carbonyl compounds, and volatile organic compounds) by revealing their possible impacts on human bodies through different action mechanisms characterized by alteration of specific biomarkers on cellular and molecular levels. In addition, this review is intended to draw the limelight that like c-cigarettes, e-cigarettes could also be accompanied with toxic effects on whole human body, which are especially apparent on respiratory system. From head to foot, from physical aspect to chemical aspect, from genotype to phenotype, potential alterations will take place upon the intake of the liquid aerosol.
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Affiliation(s)
- Shu-Jie Huang
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, Guangdong, People's Republic of China
| | - Yan-Ming Xu
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, Guangdong, People's Republic of China
| | - Andy T Y Lau
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, Guangdong, People's Republic of China
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23
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Chu H, Williams B, Schnabl B. Gut microbiota, fatty liver disease, and hepatocellular carcinoma. LIVER RESEARCH 2018; 2:43-51. [PMID: 30416839 PMCID: PMC6223644 DOI: 10.1016/j.livres.2017.11.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Intestinal bacteria contribute to the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Recently developed microbial profiling techniques are beginning to shed light on the nature of the changes in the gut microbiota that accompany NAFLD and non-alcoholic steatohepatitis (NASH). In this review, we summarize the role of gut microbiota in the development of NAFLD, NASH, and hepatocellular carcinoma (HCC). We highlight the mechanisms by which gut microbiota contribute to NAFLD/NASH, including through alterations in gut epithelial permeability, choline metabolism, endogenous alcohol production, release of inflammatory cytokines, regulation of hepatic Toll-like receptor (TLR), and bile acid metabolism. In addition, we analyze possible mechanisms for enhanced hepatic carcinogenesis, including alterations in bile acid metabolism, release of inflammatory cytokines, and expression of TLR-4. Finally, we describe therapeutic approaches for NAFLD/NASH and preventive strategies for HCC involving modulation of the intestinal microbiota or affected host pathways. Although recent studies have provided useful information, large-scale prospective studies are required to better characterize the intestinal microbiota and metabolome, in order to demonstrate a causative role for changes in the gut microbiota in the etiology of NAFLD/NASH, to identify new therapeutic strategies for NAFLD/NASH, and to develop more effective methods of preventing HCC.
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Affiliation(s)
- Huikuan Chu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Brandon Williams
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Bernd Schnabl
- Department of Medicine, University of California San Diego, La Jolla, CA, USA,epartment of Medicine, VA San Diego Healthcare System, San Diego, CA, USA,Corresponding author. Department of Medicine, University of California San Diego, Biomedical Research Facility 2 (BRF2), La Jolla, CA, USA. (B. Schnabl)
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24
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Yasuda-Onozawa Y, Handa O, Naito Y, Ushiroda C, Suyama Y, Toyokawa Y, Murakami T, Yasuda T, Ueda T, Majima A, Hotta Y, Doi T, Tanaka M, Horii Y, Higashimura Y, Mizushima K, Morita M, Uehara Y, Horie H, Fukui A, Dohi O, Okayama T, Yoshida N, Kamada K, Katada K, Uchiyama K, Ishikawa T, Takagi T, Konishi H, Itoh Y. Rebamipide upregulates mucin secretion of intestinal goblet cells via Akt phosphorylation. Mol Med Rep 2017; 16:8216-8222. [PMID: 28983630 DOI: 10.3892/mmr.2017.7647] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Accepted: 09/05/2017] [Indexed: 11/05/2022] Open
Abstract
Mucin is produced and secreted by epithelial goblet cells and is a key component of the innate immune system, acting as a barrier in the intestinal tract. However, no studies have been conducted investigating the increase in mucin secretion to enhance the intestinal barrier function. The present study investigated whether rebamipide (Reb) acts as a secretagogue of intestinal mucin and the underlying mechanisms involved, thereby focusing on the effect on goblet cells. The LS174T cell line was used as goblet cell‑like cells. Using Reb‑treated LS174T cells, the level of mucin content was assessed by periodic acid‑Schiff (PAS) staining, and mucin 2, oligomeric mucus/gel‑forming (MUC2) mRNA expression was assessed using quantitative polymerase chain reaction (PCR). Furthermore, MUC2 secretion in the supernatant was quantified by the dot blot method. The present study additionally investigated the involvement of the epidermal growth factor receptor/Akt serine/threonine kinase 1 (Akt) pathway in mucin secretion by western blotting. The results suggested that Reb strongly enhanced the positivity of PAS staining in LS174T cells, thereby suggesting increased intracellular mucin production. The PCR results indicated that Reb significantly increased MUC2 mRNA in whole cell lysate of LS174T cells. In order to assess the subsequent secretion of mucin by LS174T, MUC2 protein expression in the supernatant was assessed using the dot blot method and it was demonstrated that Reb significantly increased the secretion of MUC2 in a concentration‑dependent manner. The p‑Akt was significantly increased by Reb treatment, and an Akt inhibitor specifically suppressed MUC2 secretion. Overall, Reb increased mucin secretion directly via p‑Akt. Reb‑increased mucin may act as a strong non‑specific barrier against pathogenic stimulants in various intestinal diseases.
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Affiliation(s)
- Yuriko Yasuda-Onozawa
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Osamu Handa
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yuji Naito
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Chihiro Ushiroda
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yosuke Suyama
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yuki Toyokawa
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Takaaki Murakami
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Tomoyo Yasuda
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Tomohiro Ueda
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Atsushi Majima
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yuma Hotta
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Toshifumi Doi
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Makoto Tanaka
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yusuke Horii
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yasuki Higashimura
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Katsura Mizushima
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Mayuko Morita
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yukiko Uehara
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Hideki Horie
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Akifumi Fukui
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Osamu Dohi
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Tetsuya Okayama
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Naohisa Yoshida
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Kazuhiro Kamada
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Kazuhiro Katada
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Kazuhiko Uchiyama
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Takeshi Ishikawa
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Tomohisa Takagi
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Hideyuki Konishi
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
| | - Yoshito Itoh
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602‑8566, Japan
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25
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Mao X, Hu H, Tang J, Chen D, Yu B. Leucine increases mucin 2 and occludin production in LS174T cells partially via PI3K-Akt-mTOR pathway. ACTA ACUST UNITED AC 2016; 2:218-224. [PMID: 29767093 PMCID: PMC5941029 DOI: 10.1016/j.aninu.2016.05.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 05/25/2016] [Indexed: 11/24/2022]
Abstract
Mucin 2 and occludin play a crucial role in preserving the intestinal mucosal integrity. However, the role for leucine mediating intestinal mucin 2 and occludin expression has little been investigated. The current study was conducted to test the hypothesis that leucine treatment could increase mucin 2 and occludin levels in LS174T cells. The LS174T cells were incubated in the Dulbecco's Modified Eagle Medium (DMEM) supplementing 0, 0.5 and 5 mmol/L L-leucine for the various durations. Two hours after the leucine treatment, the inhibitor of mammalian target of rapamycin (mTOR) and protein kinase B (Akt) phosphorylation in LS174T cells were significantly increased (P < 0.05), and the mucin 2 and occludin levels were also significantly enhanced (P < 0.05). However, the pretreatment of 10 nmol/L rapamycin, which was an mTOR inhibitor, or 1 μmol/L wortmanin, which was an inhibitor of phosphatidylinositol 3-kinase (PI3K), completely inhibited leucine-induced mTOR or Akt phosphorylation (P < 0.05), and significantly reduced leucine-stimulated mucin 2 and occludin levels (P < 0.05). These results suggest that leucine treatment promotes the mucin 2 and occludin levels in LS174T cells partially through the PI3K-Akt-mTOR signaling pathway.
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Affiliation(s)
- Xiangbing Mao
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China.,Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ya'an 625014, China
| | - Haiyan Hu
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China.,Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ya'an 625014, China
| | - Jun Tang
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China.,Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ya'an 625014, China
| | - Daiwen Chen
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China.,Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ya'an 625014, China
| | - Bing Yu
- Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China.,Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ya'an 625014, China
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26
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Thomes PG, Osna NA, Bligh SM, Tuma DJ, Kharbanda KK. Role of defective methylation reactions in ethanol-induced dysregulation of intestinal barrier integrity. Biochem Pharmacol 2015; 96:30-8. [PMID: 25931143 DOI: 10.1016/j.bcp.2015.04.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 04/23/2015] [Indexed: 02/05/2023]
Abstract
Alcoholic liver disease (ALD) is a major healthcare challenge worldwide. Emerging evidence reveals that ethanol administration disrupts the intestinal epithelial tight junction (TJ) complex; this defect allows for the paracellular translocation of gut-derived pathogenic molecules to reach the liver to cause inflammation and progressive liver injury. We have previously demonstrated a causative role of impairments in liver transmethylation reactions in the pathogenesis of ALD. We have further shown that treatment with betaine, a methylation agent that normalizes liver methylation potential, can attenuate ethanol-induced liver injury. Herein, we explored whether alterations in methylation reactions play a causative role in disrupting intestinal mucosal barrier function by employing an intestinal epithelial cell line. Monolayers of Caco-2 cells were exposed to ethanol or a-pan methylation reaction inhibitor, tubercidin, in the presence and absence of betaine. The structural and functional integrity of intestinal epithelial barrier was then examined. We observed that exposure to either ethanol or tubercidin disrupted TJ integrity and function by decreasing the localization of TJ protein occludin-1 to the intracellular junctions, reducing transepithelial electrical resistance and increasing dextran influx. All these detrimental effects of ethanol and tubercidin were attenuated by co-treatment with betaine. We further show that the mechanism of betaine protection was through BHMT-mediated catalysis. Collectively, our data suggest a novel mechanism for alcohol-induced gut leakiness and identifies the importance of normal methylation reactions in maintaining TJ integrity. We also propose betaine as a potential therapeutic option for leaky gut in alcohol-consuming patients who are at the risk of developing ALD.
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Affiliation(s)
- Paul G Thomes
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Natalia A Osna
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Sarah M Bligh
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Dean J Tuma
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Kusum K Kharbanda
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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