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Lee YJ, Son SE, Im DS. Free fatty acid 3 receptor agonist AR420626 reduces allergic responses in asthma and eczema in mice. Int Immunopharmacol 2024; 127:111428. [PMID: 38159551 DOI: 10.1016/j.intimp.2023.111428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 12/15/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024]
Abstract
Free fatty acid 3 receptor (FFA3; previously GPR41) is a G protein-coupled receptor that senses short-chain fatty acids and dietary metabolites produced by the gut microbiota. FFA3 deficiency reportedly exacerbates inflammatory events in asthma. Herein, we aimed to determine the therapeutic potential of FFA3 agonists in treating inflammatory diseases. We investigated the effects of N-(2,5-dichlorophenyl)-4-(furan-2-yl)-2-methyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxamide (AR420626), an FFA3 agonist, in in vivo models of chemically induced allergic asthma and eczema in BALB/c mice. Administration of AR420626 decreased the number of immune cells in the bronchoalveolar lavage fluid and skin. AR420626 suppressed inflammatory cytokine expression in the lung and skin tissues. Histological examination revealed that AR420626 suppressed inflammation in the lungs and skin. Treatment with AR420626 significantly suppressed the enhanced lymph node size and inflammatory cytokine levels. Overall, FFA3 agonist AR420626 could suppress allergic asthma and eczema, implying that activation of FFA3 might be a therapeutic target for allergic diseases.
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Affiliation(s)
- Ye-Ji Lee
- Department of Biomedical and Pharmaceutical Sciences, Seoul 02446, Republic of Korea
| | - So-Eun Son
- Department of Fundamental Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02446, Republic of Korea
| | - Dong-Soon Im
- Department of Biomedical and Pharmaceutical Sciences, Seoul 02446, Republic of Korea; Department of Fundamental Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02446, Republic of Korea.
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2
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Li D, Zhang X, Fan Y, Zhang Y, Tao X, Yang J. Lycium barbarum Polysaccharides Improved Glucose Metabolism in Prediabetic Mice by Regulating Duodenal Contraction. Nutrients 2023; 15:4437. [PMID: 37892511 PMCID: PMC10609773 DOI: 10.3390/nu15204437] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/05/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Lycium barbarum polysaccharides (LBPs) have been shown to exert an antiglycemic effect. Emerging evidence suggests that patients with hyperglycemia have a hypercontractility of duodenum, and targeting duodenal contraction of duodenum can be beneficial to glucose metabolism. However, it is unknown whether LBPs can improve glucose metabolism by regulating the hypercontractility of the duodenum. Our aim was to explore the effect of LBPs on duodenal contraction in prediabetic mice and also preliminarily investigate the mechanism. The results showed that LBPs improved glucose homeostasis by decreasing the duodenal amplitude of contraction rather than frequency. Moreover, LBPs ameliorated the gut microbiota composition and the levels of short-chain fatty acids, especially acetic acid, which might bind to the receptor on neurons to regulate the contraction of the duodenum. Acetic acid was hypothesized to play a key role in the above process. Then, acetic acid was determined to exert an antiglycemic effect as expected. In conclusion, LBPs may rely on acetic acid to regulate duodenal contraction to ameliorate glucose metabolism in prediabetic mice, which provides a new therapeutic strategy to treat dysglycemia.
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Affiliation(s)
- Doudou Li
- School of Public Health, Ningxia Medical University, Yinchuan 750004, China; (D.L.); (X.Z.); (Y.F.); (Y.Z.); (X.T.)
| | - Xiaoke Zhang
- School of Public Health, Ningxia Medical University, Yinchuan 750004, China; (D.L.); (X.Z.); (Y.F.); (Y.Z.); (X.T.)
| | - Yanna Fan
- School of Public Health, Ningxia Medical University, Yinchuan 750004, China; (D.L.); (X.Z.); (Y.F.); (Y.Z.); (X.T.)
- Ningxia Key Laboratory of Environmental Factors and Chronic Disease Control, Yinchuan 750004, China
| | - Yannan Zhang
- School of Public Health, Ningxia Medical University, Yinchuan 750004, China; (D.L.); (X.Z.); (Y.F.); (Y.Z.); (X.T.)
- Ningxia Key Laboratory of Environmental Factors and Chronic Disease Control, Yinchuan 750004, China
| | - Xiujuan Tao
- School of Public Health, Ningxia Medical University, Yinchuan 750004, China; (D.L.); (X.Z.); (Y.F.); (Y.Z.); (X.T.)
- Ningxia Key Laboratory of Environmental Factors and Chronic Disease Control, Yinchuan 750004, China
| | - Jianjun Yang
- School of Public Health, Ningxia Medical University, Yinchuan 750004, China; (D.L.); (X.Z.); (Y.F.); (Y.Z.); (X.T.)
- Ningxia Key Laboratory of Environmental Factors and Chronic Disease Control, Yinchuan 750004, China
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Muchhala K, Kang M, Koseli E, Poklis J, Xu Q, Dewey W, Fettweis J, Jimenez N, Akbarali H. The Role of Morphine-Induced Impairment of Intestinal Epithelial Antibacterial Activity in Dysbiosis and its Impact on the Microbiota-Gut-Brain Axis.. [PMID: 37503065 PMCID: PMC10371156 DOI: 10.21203/rs.3.rs-3084467/v2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/04/2024]
Abstract
Abstract
Recent evidence suggests that chronic exposure to opioid analgesics such as morphine disrupt the intestinal epithelial layer and cause intestinal dysbiosis. Inhibiting opioid-induced dysbiosis can preclude the development of tolerance to opioid-induced antinociception, suggesting an important role of the gut-brain axis in mediating opioid effects. However, the mechanism underlying opioid-induced dysbiosis remains unclear. Host-produced antimicrobial peptides (AMPs) are critical for the integrity of the intestinal epithelial barrier as they prevent the pathogenesis of the enteric microbiota. Here, we report that chronic morphine exposure reduces expression of the antimicrobial peptide, Regenerating islet-derived 3 gamma (Reg3γ), in the ileum resulting in reduced intestinal antimicrobial activity against Gram-positive bacteria, L. reuteri. Fecal samples from morphine-treated mice had reduced levels of the phylum, Firmicutes, concomitant with reduced levels of short-chain fatty acid, butyrate. Fecal microbial transplant (FMT) from morphine-naïve mice restored the antimicrobial activity, the expression of Reg3γ, and prevented the increase in intestinal permeability and the development of antinociceptive tolerance in morphine-dependent mice. Similarly, oral gavage with sodium butyrate dose-dependently reduced the development of antinociceptive tolerance, and prevented the downregulation of Reg3γ and the reduction in antimicrobial activity. The alpha diversity of the microbiome was also restored by oral butyrate in morphine-dependent mice. These data implicate impairment of the antimicrobial activity of the intestinal epithelium as a mechanism by which morphine disrupts the microbiota-gut-brain axis.
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Muchhala K, Kang M, Koseli E, Poklis J, Xu Q, Dewey W, Fettweis J, Jimenez N, Akbarali H. The Role of Morphine-Induced Impairment of Intestinal Epithelial Antibacterial Activity in Dysbiosis and its Impact on the Microbiota-Gut-Brain Axis. RESEARCH SQUARE 2023:rs.3.rs-3084467. [PMID: 37503065 PMCID: PMC10371156 DOI: 10.21203/rs.3.rs-3084467/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Recent evidence suggests that chronic exposure to opioid analgesics such as morphine disrupt the intestinal epithelial layer and cause intestinal dysbiosis. Inhibiting opioid-induced dysbiosis can preclude the development of tolerance to opioid-induced antinociception, suggesting an important role of the gut-brain axis in mediating opioid effects. However, the mechanism underlying opioid-induced dysbiosis remains unclear. Host-produced antimicrobial peptides (AMPs) are critical for the integrity of the intestinal epithelial barrier as they prevent the pathogenesis of the enteric microbiota. Here, we report that chronic morphine exposure reduces expression of the antimicrobial peptide, Regenerating islet-derived 3 gamma (Reg3γ), in the ileum resulting in reduced intestinal antimicrobial activity against Gram-positive bacteria, L. reuteri. Fecal samples from morphine-treated mice had reduced levels of the phylum, Firmicutes, concomitant with reduced levels of short-chain fatty acid, butyrate. Fecal microbial transplant (FMT) from morphine-naïve mice restored the antimicrobial activity, the expression of Reg3γ, and prevented the increase in intestinal permeability and the development of antinociceptive tolerance in morphine-dependent mice. Similarly, oral gavage with sodium butyrate dose-dependently reduced the development of antinociceptive tolerance, and prevented the downregulation of Reg3γ and the reduction in antimicrobial activity. The alpha diversity of the microbiome was also restored by oral butyrate in morphine-dependent mice. These data implicate impairment of the antimicrobial activity of the intestinal epithelium as a mechanism by which morphine disrupts the microbiota-gut-brain axis.
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Calabrò S, Kankowski S, Cescon M, Gambarotta G, Raimondo S, Haastert-Talini K, Ronchi G. Impact of Gut Microbiota on the Peripheral Nervous System in Physiological, Regenerative and Pathological Conditions. Int J Mol Sci 2023; 24:ijms24098061. [PMID: 37175764 PMCID: PMC10179357 DOI: 10.3390/ijms24098061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/21/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
It has been widely demonstrated that the gut microbiota is responsible for essential functions in human health and that its perturbation is implicated in the development and progression of a growing list of diseases. The number of studies evaluating how the gut microbiota interacts with and influences other organs and systems in the body and vice versa is constantly increasing and several 'gut-organ axes' have already been defined. Recently, the view on the link between the gut microbiota (GM) and the peripheral nervous system (PNS) has become broader by exceeding the fact that the PNS can serve as a systemic carrier of GM-derived metabolites and products to other organs. The PNS as the communication network between the central nervous system and the periphery of the body and internal organs can rather be affected itself by GM perturbation. In this review, we summarize the current knowledge about the impact of gut microbiota on the PNS, with regard to its somatic and autonomic divisions, in physiological, regenerative and pathological conditions.
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Affiliation(s)
- Sonia Calabrò
- Department of Molecular Medicine, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131 Padova, Italy
| | - Svenja Kankowski
- Hannover Medical School, Institute of Neuroanatomy and Cell Biology, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Matilde Cescon
- Department of Molecular Medicine, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Giovanna Gambarotta
- Department of Clinical and Biological Sciences & Neuroscience Institute Cavalieri Ottolenghi (NICO), University of Torino, Regione Gonzole 10, Orbassano, 10043 Torino, Italy
| | - Stefania Raimondo
- Department of Clinical and Biological Sciences & Neuroscience Institute Cavalieri Ottolenghi (NICO), University of Torino, Regione Gonzole 10, Orbassano, 10043 Torino, Italy
| | - Kirsten Haastert-Talini
- Hannover Medical School, Institute of Neuroanatomy and Cell Biology, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Center for Systems Neuroscience Hannover (ZSN), Buenteweg 2, 30559 Hannover, Germany
| | - Giulia Ronchi
- Department of Clinical and Biological Sciences & Neuroscience Institute Cavalieri Ottolenghi (NICO), University of Torino, Regione Gonzole 10, Orbassano, 10043 Torino, Italy
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6
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Li A, Zheng J, Han X, Jiang Z, Yang B, Yang S, Zhou W, Li C, Sun M. Health implication of lactose intolerance and updates on its dietary management. Int Dairy J 2023. [DOI: 10.1016/j.idairyj.2023.105608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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7
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Jiang W, Wu J, Zhu S, Xin L, Yu C, Shen Z. The Role of Short Chain Fatty Acids in Irritable Bowel Syndrome. J Neurogastroenterol Motil 2022; 28:540-548. [PMID: 36250361 PMCID: PMC9577580 DOI: 10.5056/jnm22093] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 10/07/2022] [Indexed: 11/20/2022] Open
Abstract
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that is characterized by abdominal pain and disordered bowel habits. The etiology of IBS is multifactorial, including abnormal gut-brain interactions, visceral hypersensitivity, altered colon motility, and psychological factors. Recent studies have shown that the intestinal microbiota and its metabolites short chain fatty acids (SCFAs) may be involved in the pathogenesis of IBS. SCFAs play an important role in the pathophysiology of IBS. We discuss the underlying mechanisms of action of SCFAs in intestinal inflammation and immunity, intestinal barrier integrity, motility, and the microbiota-gut-brain axis. Limited to previous studies, further studies are required to investigate the mechanisms of action of SCFAs in IBS and provide more precise therapeutic strategies for IBS.
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Affiliation(s)
- Wenxi Jiang
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Jiali Wu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Shefeng Zhu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Linying Xin
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Chaohui Yu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Zhe Shen
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
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8
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Geng ZH, Zhu Y, Li QL, Zhao C, Zhou PH. Enteric Nervous System: The Bridge Between the Gut Microbiota and Neurological Disorders. Front Aging Neurosci 2022; 14:810483. [PMID: 35517052 PMCID: PMC9063565 DOI: 10.3389/fnagi.2022.810483] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 01/17/2022] [Indexed: 12/12/2022] Open
Abstract
The gastrointestinal (GI) tract plays an essential role in food digestion, absorption, and the mucosal immune system; it is also inhabited by a huge range of microbes. The GI tract is densely innervated by a network of 200–600 million neurons that comprise the enteric nervous system (ENS). This system cooperates with intestinal microbes, the intestinal immune system, and endocrine systems; it forms a complex network that is required to maintain a stable intestinal microenvironment. Understanding how gut microbes influence the ENS and central nervous system (CNS) has been a significant research subject over the past decade. Moreover, accumulating evidence from animal and clinical studies has revealed that gut microbiota play important roles in various neurological diseases. However, the causal relationship between microbial changes and neurological disorders currently remains unproven. This review aims to summarize the possible contributions of GI microbiota to the ENS and CNS. It also provides new insights into furthering our current understanding of neurological disorders.
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Affiliation(s)
- Zi-Han Geng
- Endoscopy Center and Endoscopy Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yan Zhu
- Endoscopy Center and Endoscopy Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Quan-Lin Li
- Endoscopy Center and Endoscopy Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China
- Shanghai Collaborative Innovation Center of Endoscopy, Shanghai, China
- *Correspondence: Quan-Lin Li,
| | - Chao Zhao
- Endoscopy Center and Endoscopy Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China
- Key Laboratory of Medical Molecular Virology, School of Basic Medical Sciences & National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Chao Zhao,
| | - Ping-Hong Zhou
- Endoscopy Center and Endoscopy Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China
- Shanghai Collaborative Innovation Center of Endoscopy, Shanghai, China
- Ping-Hong Zhou,
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9
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O'Riordan KJ, Collins MK, Moloney GM, Knox EG, Aburto MR, Fülling C, Morley SJ, Clarke G, Schellekens H, Cryan JF. Short chain fatty acids: Microbial metabolites for gut-brain axis signalling. Mol Cell Endocrinol 2022; 546:111572. [PMID: 35066114 DOI: 10.1016/j.mce.2022.111572] [Citation(s) in RCA: 108] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 02/08/2023]
Abstract
The role of the intestinal microbiota as a regulator of gut-brain axis signalling has risen to prominence in recent years. Understanding the relationship between the gut microbiota, the metabolites it produces, and the brain will be critical for the subsequent development of new therapeutic approaches, including the identification of novel psychobiotics. A key focus in this regard have been the short-chain fatty acids (SCFAs) produced by bacterial fermentation of dietary fibre, which include butyrate, acetate, and propionate. Ongoing research is focused on the entry of SCFAs into systemic circulation from the gut lumen, their migration to cerebral circulation and across the blood brain barrier, and their potential to exert acute and chronic effects on brain structure and function. This review aims to discuss our current mechanistic understanding of the direct and indirect influence that SCFAs have on brain function, behaviour and physiology, which will inform future microbiota-targeted interventions for brain disorders.
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Affiliation(s)
| | - Michael K Collins
- APC Microbiome Ireland, University College Cork, Ireland; Department of Anatomy & Neuroscience, University College Cork, Ireland
| | - Gerard M Moloney
- APC Microbiome Ireland, University College Cork, Ireland; Department of Anatomy & Neuroscience, University College Cork, Ireland
| | - Emily G Knox
- APC Microbiome Ireland, University College Cork, Ireland; School of Pharmacy, University College Cork, Ireland
| | - María R Aburto
- APC Microbiome Ireland, University College Cork, Ireland
| | | | - Shane J Morley
- APC Microbiome Ireland, University College Cork, Ireland
| | - Gerard Clarke
- APC Microbiome Ireland, University College Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland
| | - Harriët Schellekens
- APC Microbiome Ireland, University College Cork, Ireland; Department of Anatomy & Neuroscience, University College Cork, Ireland
| | - John F Cryan
- APC Microbiome Ireland, University College Cork, Ireland; Department of Anatomy & Neuroscience, University College Cork, Ireland.
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Lymperopoulos A, Suster MS, Borges JI. Short-Chain Fatty Acid Receptors and Cardiovascular Function. Int J Mol Sci 2022; 23:ijms23063303. [PMID: 35328722 PMCID: PMC8952772 DOI: 10.3390/ijms23063303] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/15/2022] [Accepted: 03/17/2022] [Indexed: 02/06/2023] Open
Abstract
Increasing experimental and clinical evidence points toward a very important role for the gut microbiome and its associated metabolism in human health and disease, including in cardiovascular disorders. Free fatty acids (FFAs) are metabolically produced and utilized as energy substrates during almost every biological process in the human body. Contrary to long- and medium-chain FFAs, which are mainly synthesized from dietary triglycerides, short-chain FFAs (SCFAs) derive from the gut microbiota-mediated fermentation of indigestible dietary fiber. Originally thought to serve only as energy sources, FFAs are now known to act as ligands for a specific group of cell surface receptors called FFA receptors (FFARs), thereby inducing intracellular signaling to exert a variety of cellular and tissue effects. All FFARs are G protein-coupled receptors (GPCRs) that play integral roles in the regulation of metabolism, immunity, inflammation, hormone/neurotransmitter secretion, etc. Four different FFAR types are known to date, with FFAR1 (formerly known as GPR40) and FFAR4 (formerly known as GPR120) mediating long- and medium-chain FFA actions, while FFAR3 (formerly GPR41) and FFAR2 (formerly GPR43) are essentially the SCFA receptors (SCFARs), responding to all SCFAs, including acetic acid, propionic acid, and butyric acid. As with various other organ systems/tissues, the important roles the SCFARs (FFAR2 and FFAR3) play in physiology and in various disorders of the cardiovascular system have been revealed over the last fifteen years. In this review, we discuss the cardiovascular implications of some key (patho)physiological functions of SCFAR signaling pathways, particularly those regulating the neurohormonal control of circulation and adipose tissue homeostasis. Wherever appropriate, we also highlight the potential of these receptors as therapeutic targets for cardiovascular disorders.
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Fung C, Cools B, Malagola S, Martens T, Tack J, Kazwiny Y, Vanden Berghe P. Luminal short-chain fatty acids and 5-HT acutely activate myenteric neurons in the mouse proximal colon. Neurogastroenterol Motil 2021; 33:e14186. [PMID: 34121274 DOI: 10.1111/nmo.14186] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 04/03/2021] [Accepted: 05/04/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Gastrointestinal (GI) function is critically dependent on the control of the enteric nervous system (ENS), which is situated within the gut wall and organized into two ganglionated nerve plexuses: the submucosal and myenteric plexus. The ENS is optimally positioned and together with the intestinal epithelium, is well-equipped to monitor the luminal contents such as microbial metabolites and to coordinate appropriate responses accordingly. Despite the heightened interest in the gut microbiota and its influence on intestinal physiology and pathophysiology, how they interact with the host ENS remains unclear. METHODS Using full-thickness proximal colon preparations from transgenic Villin-CreERT2;R26R-GCaMP3 and Wnt1-Cre;R26R-GCaMP3 mice, which express a fluorescent Ca2+ indicator in their intestinal epithelium or in their ENS, respectively, we examined the effects of key luminal microbial metabolites (SCFAs and 5-HT) on the mucosa and underlying enteric neurons. KEY RESULTS We show that the SCFAs acetate, propionate, and butyrate, as well as 5-HT can, to varying extents, acutely elicit epithelial and neuronal Ca2+ responses. Furthermore, SCFAs exert differential effects on submucosal and myenteric neurons. Additionally, we found that submucosal ganglia are predominantly aligned along the striations of the transverse mucosal folds in the proximal colon. CONCLUSIONS & INFERENCES Taken together, our study demonstrates that different microbial metabolites, including SCFAs and 5-HT, can acutely stimulate Ca2+ signaling in the mucosal epithelium and in enteric neurons.
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Affiliation(s)
- Candice Fung
- Laboratory for Enteric NeuroScience (LENS) Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Bert Cools
- Laboratory for Enteric NeuroScience (LENS) Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Sergio Malagola
- Laboratory for Enteric NeuroScience (LENS) Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Tobias Martens
- Laboratory for Enteric NeuroScience (LENS) Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Jan Tack
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Youcef Kazwiny
- Laboratory for Enteric NeuroScience (LENS) Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Pieter Vanden Berghe
- Laboratory for Enteric NeuroScience (LENS) Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
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Neuro-immune-metabolism: The tripod system of homeostasis. Immunol Lett 2021; 240:77-97. [PMID: 34655659 DOI: 10.1016/j.imlet.2021.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 09/30/2021] [Accepted: 10/08/2021] [Indexed: 11/20/2022]
Abstract
Homeostatic regulation of cellular and molecular processes is essential for the efficient physiological functioning of body organs. It requires an intricate balance of several networks throughout the body, most notable being the nervous, immune and metabolic systems. Several studies have reported the interactions between neuro-immune, immune-metabolic and neuro-metabolic pathways. Current review aims to integrate the information and show that neuro, immune and metabolic systems form the triumvirate of homeostasis. It focuses on the cellular and molecular interactions occurring in the extremities and intestine, which are innervated by the peripheral nervous system and for the intestine in particular the enteric nervous system. While the interdependence of neuro-immune-metabolic pathways provides a fallback mechanism in case of disruption of homeostasis, in chronic pathologies of continued disequilibrium, the collapse of one system spreads to the other interacting networks as well. Current review illustrates this domino-effect using diabetes as the main example. Together, this review attempts to provide a holistic picture of the integrated network of neuro-immune-metabolism and attempts to broaden the outlook when devising a scientific study or a treatment strategy.
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13
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Nakamori H, Noda K, Mitsui R, Hashitani H. Role of enteric dopaminergic neurons in regulating peristalsis of rat proximal colon. Neurogastroenterol Motil 2021; 33:e14127. [PMID: 33939231 DOI: 10.1111/nmo.14127] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 02/11/2021] [Accepted: 03/02/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND Constipation is commonly seen in patients with Parkinson's disease associated with a loss of dopaminergic neurons in both central and enteric nervous systems. However, the roles of enteric dopaminergic neurons in developing constipation remain to be elucidated. Here, we investigated the roles of enteric dopaminergic neurons in the generation of colonic peristalsis. METHODS Cannulated segments of rat proximal colon were situated in the organ bath, abluminally perfused with physiological salt solution and luminally perfused with 0.9% saline. Drugs were applied in the abluminal solution. Changes in diameter along the length of the colonic segment were captured by a video camera and transformed into spatio-temporal maps. Fluorescence immunohistochemistry was also carried out. KEY RESULTS Blockade of nitrergic neurotransmission prevented oro-aboral propagation of peristaltic waves and caused a colonic constriction without affecting ripples, non-propagating myogenic contractions. Blockade of cholinergic neurotransmission also prevented peristaltic waves but suppressed ripples with a colonic dilatation. Tetrodotoxin (0.6 μM) abolished peristaltic waves and increased ripples with a constriction. SCH 23390 (20 μM), a D1 -like dopamine receptor antagonist, slowed the peristaltic waves and caused a constriction, while GBR 12909 (1 μM), a dopamine reuptake inhibitor, diminished the peristaltic waves with a dilatation. Bath-applied dopamine (3 μM) abolished the peristaltic waves associated with a colonic dilation in an SCH 23390 (5 μM)-sensitive manner. D1 receptor immunoreactivity was co-localized to nitrergic and cholinergic neurons. CONCLUSIONS AND INFERENCES Dopaminergic neurons appear to facilitate nitrergic neurons via D1 -like receptors to stabilize asynchronous contractile activity resulting in the generation of colonic peristalsis.
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Affiliation(s)
- Hiroyuki Nakamori
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Kenta Noda
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Retsu Mitsui
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Hikaru Hashitani
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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14
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Kuwahara A, Matsuda K, Kuwahara Y, Asano S, Inui T, Marunaka Y. Microbiota-gut-brain axis: enteroendocrine cells and the enteric nervous system form an interface between the microbiota and the central nervous system. Biomed Res 2021; 41:199-216. [PMID: 33071256 DOI: 10.2220/biomedres.41.199] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The microbiota-gut-brain axis transmits bidirectional communication between the gut and the central nervous system and links the emotional and cognitive centers of the brain with peripheral gut functions. This communication occurs along the axis via local, paracrine, and endocrine mechanisms involving a variety of gut-derived peptide/amine produced by enteroendocrine cells. Neural networks, such as the enteric nervous system, and the central nervous system, including the autonomic nervous system, also transmit information through the microbiota-gut-brain axis. Recent advances in research have described the importance of the gut microbiota in influencing normal physiology and contributing to disease. We are only beginning to understand this bidirectional communication system. In this review, we summarize the available data supporting the existence of these interactions, highlighting data related to the contribution of enteroendocrine cells and the enteric nervous system as an interface between the gut microbiota and brain.
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Affiliation(s)
- Atsukazu Kuwahara
- Research Unit for Epithelial Physiology and Research Center for Drug Discovery and Pharmaceutical Development Science, Research Organization of Science and Technology, Ritsumeikan University
| | - Kyoko Matsuda
- Department of Molecular Physiology, College of Pharmaceutical Sciences, Ritsumeikan University
| | - Yuko Kuwahara
- Research Unit for Epithelial Physiology and Research Center for Drug Discovery and Pharmaceutical Development Science, Research Organization of Science and Technology, Ritsumeikan University
| | - Shinji Asano
- Department of Molecular Physiology, College of Pharmaceutical Sciences, Ritsumeikan University
| | | | - Yoshinori Marunaka
- Research Unit for Epithelial Physiology and Research Center for Drug Discovery and Pharmaceutical Development Science, Research Organization of Science and Technology, Ritsumeikan University.,Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine.,Research Institute for Clinical Physiology, Kyoto Industrial Health Association
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15
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Metzler-Zebeli BU, Sener-Aydemir A, Sharma S, Lerch F. Postnatal development of gut microbial activity and their importance for jejunal motility in piglets. J Anim Sci 2021; 99:6283768. [PMID: 34036356 DOI: 10.1093/jas/skab171] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 05/21/2021] [Indexed: 12/11/2022] Open
Abstract
Despite their anti-inflammatory properties, role in barrier function, absorption and microbial balance in the gut, knowledge on maturational and dietary effects on intestinal short-chain fatty acids (SCFA) in neonatal piglets is scarce. Moreover, little information exists whether SCFA and lactic acid (LA) modulates gut motility at this age. The present study aimed (1) to investigate the maturational changes in the SCFA profile with and without creep feeding of piglets in the first 3 wk of life; and (2) to examine the effects of SCFA and LA on muscle contractibility in jejunal tissue from neonatal piglets ex vivo. SCFA concentrations were measured in fecal samples of 52 piglets from 10 litters collected on days 2, 6, 13, and 20 of life using gas chromatography. Half of the litters were fed a commercial creep feed from day 10 of life. The organ bath system was used to test the effect of SCFA (acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and caproate) as well as of LA and the combination of LA and SCFA on muscle contractibility in piglet's jejunum. Average daily gain of piglets was similar between groups before and after introduction of creep feed. SCFA were detectable in feces in relevant concentrations from day 2 of life and increased on day 6 in males by 3.0-fold and on day 13 in females by 1.6-fold but decreased again on day 20 in both sexes compared with day 2 (P < 0.05). Creep feeding reduced fecal SCFA by 0.6-fold on day 13 without largely modifying molar proportions, whereas it increased fecal SCFA by 0.8-fold on day 20 of life compared with the sow-reared only piglets (P < 0.05). Applying SCFA ex vivo increased the muscle contraction of the jejunum by 30% (P < 0.05). Likewise, addition of LA and the combination of LA and SCFA increased the jejunal muscle contractibility by 34.9% and 32.2%, respectively, compared with the muscle tension preaddition (P < 0.05). In conclusion, the present results for fecal SCFA in first days of life suggest high bacterial activity on milk components and emphasize the importance of SCFA for intestinal development and function. After a lag phase, creep feeding promotes fermentation in the distal colon, which may be beneficial for the gut homeostasis. Results further demonstrate the stimulating effect of SCFA and LA for jejunal motility, suggesting a role for mixing of digesta (segmentation) and digestion and absorption of nutrients as well as passage in the jejunum of neonatal piglets.
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Affiliation(s)
- Barbara U Metzler-Zebeli
- Unit of Nutritional Physiology, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
- Christian-Doppler Laboratory for Innovative Gut Health Concepts of Livestock, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Arife Sener-Aydemir
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - S Sharma
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Frederike Lerch
- Unit of Nutritional Physiology, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
- Christian-Doppler Laboratory for Innovative Gut Health Concepts of Livestock, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
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16
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Ballout J, Akiba Y, Kaunitz JD, Diener M. Short-chain fatty acid receptors involved in epithelial acetylcholine release in rat caecum. Eur J Pharmacol 2021; 906:174292. [PMID: 34216575 DOI: 10.1016/j.ejphar.2021.174292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/17/2021] [Accepted: 06/25/2021] [Indexed: 10/21/2022]
Abstract
Short-chain fatty acids (SCFAs) produced by the microbial fermentation of carbohydrates are important energy substrates for mammals. Intestinal epithelia respond to these metabolites by stimulation of anion secretion via the release of epithelial acetylcholine. The present experiments were performed to discover which of the known receptors for SCFAs are expressed in rat caecum, the most important site of fermentation within the intestine of non-ruminant mammals. Using the increase in short-circuit current (Isc) induced by anion secretion as the readout, the order of efficiency of the tested SCFAs in rat caecum was propionate > butyrate > acetate. Both synthetic high-affinity selective free fatty acid (FFA) receptor agonists 4-CMTB (FFA2 receptor) and AR420626 (FFA3 receptor) partially mimicked the effect of propionate on Isc (IProp). IProp was concentration-dependently inhibited by the FFA3 receptor antagonist β-OH-butyrate. Although no antagonist of rat FFA2 receptor is available, coadministration of the allosteric FFA2 receptor agonist 4-CMTB together with a low concentration of propionate potentiated IProp, suggesting that FFA2 receptor is involved in sensing of short-chain fatty acids as well. The expression of both receptor types was confirmed by qPCR (with FFA2 > FFA3 receptor). Immunohistochemical staining revealed the localization of FFA2 receptor in the surface epithelium and the FFA3 receptor expression predominantly in enteroendocrine cells and subepithelial nerve-like fibers. Taken together, the present results demonstrate that the anion secretion induced by the microbial metabolite propionate in rat caecum is enhanced by activation of FFA2 and FFA3 receptor expressed in different cell types within the caecal epithelium.
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Affiliation(s)
- Jasmin Ballout
- Institute for Veterinary Physiology and Biochemistry, Justus Liebig University Giessen, Germany
| | - Yasutada Akiba
- Greater Los Angeles Veterans Affairs Healthcare System, University of California Los Angeles, School of Medicine, CA, 90073, USA; Department of Medicine, University of California Los Angeles, School of Medicine, CA, 90073, USA
| | - Jonathan D Kaunitz
- Greater Los Angeles Veterans Affairs Healthcare System, University of California Los Angeles, School of Medicine, CA, 90073, USA; Department of Medicine, University of California Los Angeles, School of Medicine, CA, 90073, USA; Department of Surgery, University of California Los Angeles, School of Medicine, CA, 90073, USA
| | - Martin Diener
- Institute for Veterinary Physiology and Biochemistry, Justus Liebig University Giessen, Germany.
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17
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Nicotinic Acetylcholine Receptor Involvement in Inflammatory Bowel Disease and Interactions with Gut Microbiota. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18031189. [PMID: 33572734 PMCID: PMC7908252 DOI: 10.3390/ijerph18031189] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 12/12/2022]
Abstract
The gut-brain axis describes a complex interplay between the central nervous system and organs of the gastrointestinal tract. Sensory neurons of dorsal root and nodose ganglia, neurons of the autonomic nervous system, and immune cells collect and relay information about the status of the gut to the brain. A critical component in this bi-directional communication system is the vagus nerve which is essential for coordinating the immune system’s response to the activities of commensal bacteria in the gut and to pathogenic strains and their toxins. Local control of gut function is provided by networks of neurons in the enteric nervous system also called the ‘gut-brain’. One element common to all of these gut-brain systems is the expression of nicotinic acetylcholine receptors. These ligand-gated ion channels serve myriad roles in the gut-brain axis including mediating fast synaptic transmission between autonomic pre- and postganglionic neurons, modulation of neurotransmitter release from peripheral sensory and enteric neurons, and modulation of cytokine release from immune cells. Here we review the role of nicotinic receptors in the gut-brain axis with a focus on the interplay of these receptors with the gut microbiome and their involvement in dysregulation of gut function and inflammatory bowel diseases.
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18
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Shaidullov IF, Sorokina DM, Sitdikov FG, Hermann A, Abdulkhakov SR, Sitdikova GF. Short chain fatty acids and colon motility in a mouse model of irritable bowel syndrome. BMC Gastroenterol 2021; 21:37. [PMID: 33499840 PMCID: PMC7836204 DOI: 10.1186/s12876-021-01613-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 01/14/2021] [Indexed: 12/14/2022] Open
Abstract
Background Irritable bowel syndrome (IBS) is defined as a multifactorial disorder associated with visceral hypersensitivity, altered gut motility and dysfunction of the brain-gut axis. Gut microbiota and its metabolites are proposed as possible etiological factors of IBS. Short chain fatty acids (SCFAs) induce both inhibitory and stimulatory action on colon motility, however, their effects on the IBS model were not investigated. The aim of our study was to investigate the level of SFCAs in feces and their effects on colon motility in a mouse model of IBS. Methods IBS model was induced in mice by intracolonic infusion of 1% acetic acid during the early postnatal period. Mice colon hypersensitivity was assessed by the threshold of the abdominal withdrawal reflex in response to colorectal distention. Colon contractility was studied using proximal colon specimens in isometric conditions. Transit rates were assessed by the pellet propulsion in the isolated colon. Concentrations of SCFAs in feces were measured using gas–liquid chromatography. Results The concentration of SCFAs in feces of IBS model mice was higher compared to the control group. Visceral sensitivity to colorectal distension and colonic transit rate were increased indicating IBS with predominant diarrhea. The frequency and amplitude of spontaneous contractions of proximal colon segments from IBS mice were higher, but carbachol induced contractions were lower compared to control. During acute application of SCFAs (sodium propionate, sodium acetate or butyric acid) dose-dependently (0.5–30 mM) decreased tonic tension, frequency and amplitude of spontaneous and carbachol-evoked contractions. In the mouse IBS group the inhibitory effects SCFAs on spontaneous and carbachol-evoked contractions were less pronounced. At the same time intraluminal administration of butyrate (5 mM) increased the transit rate in the colon of both groups, but its stimulatory effect was more pronounced in mouse IBS model group. Conclusion Our data indicate that the increased transit rate in the mouse IBS model group is associated with a disbalance of activating and inhibiting action of SCFAs due to chronically elevated SCFA levels, which may impact the pathogenesis of IBS with predominant diarrhea syndrome.
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Affiliation(s)
- Ilnar F Shaidullov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 18, Kremlevskaya str., 420008, Kazan, Russia
| | - Dina M Sorokina
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 18, Kremlevskaya str., 420008, Kazan, Russia
| | - Farit G Sitdikov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 18, Kremlevskaya str., 420008, Kazan, Russia
| | - Anton Hermann
- Department of Biosciences, University of Salzburg, Hellbrunnerstr.34, 5020, Salzburg, Austria
| | - Sayar R Abdulkhakov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 18, Kremlevskaya str., 420008, Kazan, Russia
| | - Guzel F Sitdikova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 18, Kremlevskaya str., 420008, Kazan, Russia.
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19
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Rea K, Dinan TG, Cryan JF. Gut Microbiota: A Perspective for Psychiatrists. Neuropsychobiology 2020; 79:50-62. [PMID: 31726457 DOI: 10.1159/000504495] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/31/2019] [Indexed: 11/19/2022]
Abstract
There is mounting evidence that the trillions of microbes that inhabit our gut are a substantial contributing factor to mental health and, equally, to the progression of neuropsychiatric disorders. The extraordinary complexity of the gut ecosystem, and how it interacts with the intestinal epithelium to manifest physiological changes in the brain to influence mood and behaviour, has been the subject of intense scientific scrutiny over the last 2 decades. To further complicate matters, we each harbour a unique microbiota community that is subject to change by a number of factors including diet, exercise, stress, health status, genetics, medication, and age, amongst others. The microbiota-gut-brain axis is a dynamic matrix of tissues and organs including the gastrointestinal (GI) microbiota, immune cells, gut tissue, glands, the autonomic nervous system (ANS), and the brain that communicate in a complex multidirectional manner through a number of anatomically and physiologically distinct systems. Long-term perturbations to this homeostatic environment may contribute to the progression of a number of disorders by altering physiological processes including hypothalamic-pituitary-adrenal axis activation, neurotransmitter systems, immune function, and the inflammatory response. While an appropriate, co-ordinated physiological response, such as an immune or stress response, is necessary for survival, a dysfunctional response can be detrimental to the host, contributing to the development of a number of central nervous system disorders.
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Affiliation(s)
- Kieran Rea
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland
| | - John F Cryan
- APC Microbiome Ireland, University College Cork, Cork, Ireland, .,Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland,
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20
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Kaji I, Roland JT, Watanabe M, Engevik AC, Goldstein AE, Hodges CA, Goldenring JR. Lysophosphatidic Acid Increases Maturation of Brush Borders and SGLT1 Activity in MYO5B-deficient Mice, a Model of Microvillus Inclusion Disease. Gastroenterology 2020; 159:1390-1405.e20. [PMID: 32534933 PMCID: PMC8240502 DOI: 10.1053/j.gastro.2020.06.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 05/29/2020] [Accepted: 06/03/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIM Myosin VB (MYO5B) is an essential trafficking protein for membrane recycling in gastrointestinal epithelial cells. The inactivating mutations of MYO5B cause the congenital diarrheal disease, microvillus inclusion disease (MVID). MYO5B deficiency in mice causes mislocalization of SGLT1 and NHE3, but retained apical function of CFTR, resulting in malabsorption and secretory diarrhea. Activation of lysophosphatidic acid (LPA) receptors can improve diarrhea, but the effect of LPA on MVID symptoms is unclear. We investigated whether LPA administration can reduce the epithelial deficits in MYO5B-knockout mice. METHODS Studies were conducted with tamoxifen-induced, intestine-specific knockout of MYO5B (VilCreERT2;Myo5bflox/flox) and littermate controls. Mice were given LPA, an LPAR2 agonist (GRI977143), or vehicle for 4 days after a single injection of tamoxifen. Apical SGLT1 and CFTR activities were measured in Üssing chambers. Intestinal tissues were collected, and localization of membrane transporters was evaluated by immunofluorescence analysis in tissue sections and enteroids. RNA sequencing and enrichment analysis were performed with isolated jejunal epithelial cells. RESULTS Daily administration of LPA reduced villus blunting, frequency of multivesicular bodies, and levels of cathepsins in intestinal tissues of MYO5B-knockout mice compared with vehicle administration. LPA partially restored the brush border height and the localization of SGLT1 and NHE3 in small intestine of MYO5B-knockout mice and enteroids. The SGLT1-dependent short-circuit current was increased and abnormal CFTR activities were decreased in jejunum from MYO5B-knockout mice given LPA compared with vehicle. CONCLUSIONS LPA may regulate a MYO5B-independent trafficking mechanism and brush border maturation, and therefore be developed for treatment of MVID.
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Affiliation(s)
- Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.
| | - Joseph T. Roland
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | | | - Amy C. Engevik
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | - Anna E. Goldstein
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | - Craig A. Hodges
- Cystic Fibrosis Mouse Models Resource Center, Case Western Reserve University, Cleveland, OH
| | - James R. Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan,Cell and Developmental Biology, Vanderbilt University School of Medicine, Sapporo, Japan,Nashville Veterans Affairs Medical Center, Nashville TN
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21
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Xue H, Zhang M, Ma J, Chen T, Wang F, Tang X. Lactose-Induced Chronic Diarrhea Results From Abnormal Luminal Microbial Fermentation and Disorder of Ion Transport in the Colon. Front Physiol 2020; 11:877. [PMID: 32848839 PMCID: PMC7403511 DOI: 10.3389/fphys.2020.00877] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 06/29/2020] [Indexed: 12/12/2022] Open
Abstract
Diarrhea is one of the major abdominal symptoms in lactose-intolerant subjects. The changes in the large intestinal luminal environment and disorder of the epithelial ion transport in lactose-induced diarrhea remain unclear. The present study aimed to investigate the effect of an incremental high-lactose diet (IHLD, 30%/40%/50%) on luminal microbiota, microbiota-derived metabolite concentrations and colonic ion transport. Gut microbiota were analyzed by 16S rRNA amplicon sequencing and the concentration of SCFAs by gas chromatography, galactose, lactose and lactic acid through assay kit; Ussing chamber was performed to detect basal and stimulated ion transport; The expression and location of SCFA transporters, the Na-H exchanger 3(NHE3), cystic fibrosis transporter regulater (CFTR) and NKCC1 in the colon mucosa were analyzed by western and immunostaining. The concentrations of lactose, galactose and lactic acid of the cecal content were markedly increased (P < 0.01) and SCFA concentration was significantly decreased (P < 0.01). This was associated with depletion of the Lachnospiraceae NK4A136 group and Ruminococcaceae UCG-005 and increased relative abundance of Lactobacillus, escherichia-shigella and megamonas in the cecal microbiota. The expression of monocarboxylate transporter 1 was decreased in the colonic mucosa of the IHLD group. Low NHE3 expression and phosphorylation levels, and decreases in delta basal short circuit current after apical Na+ removal in the colonic mucosa of the IHLD group contributed to Na+ accumulation in the lumen and decrease stimulated Cl– secretion with low CFTR and NKCC1 expression would compensate for water and electrolyte loss during the diarrhea process. These results indicated that the persistence of the diarrhea state was maintained by abnormal colonic microbiota fermentation leading to high concentrations of lactose, galactose and lactic acid and low SCFAs in the lumen, and decreased Na+ absorption with the low NHE3 expression and phosphorylation levels.
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Affiliation(s)
- Hong Xue
- Digestive Laboratory of Traditional Chinese Medicine Research Institute of Spleen and Stomach Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Min Zhang
- Digestive Laboratory of Traditional Chinese Medicine Research Institute of Spleen and Stomach Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jinxin Ma
- Digestive Laboratory of Traditional Chinese Medicine Research Institute of Spleen and Stomach Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Ting Chen
- Digestive Laboratory of Traditional Chinese Medicine Research Institute of Spleen and Stomach Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Fengyun Wang
- Digestive Laboratory of Traditional Chinese Medicine Research Institute of Spleen and Stomach Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xudong Tang
- Digestive Laboratory of Traditional Chinese Medicine Research Institute of Spleen and Stomach Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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22
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Bolognini D, Dedeo D, Milligan G. Metabolic and inflammatory functions of short-chain fatty acid receptors. ACTA ACUST UNITED AC 2020; 16:1-9. [PMID: 32835130 PMCID: PMC7332907 DOI: 10.1016/j.coemr.2020.06.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
FFA2 and FFA3 are receptors for short-chain fatty acids which are produced in prodigious amounts by fermentation of poorly digested carbohydrates by gut bacteria. Understanding the roles of these receptors in regulating enteroendocrine, metabolic and immune functions has developed with the production and use of novel pharmacological tools and animal models. A complex (patho)physiological scenario is now emerging in which strategic expression of FFA2 and FFA3 in key cell types and selective modulation of their signalling might regulate body weight management, energy homoeostasis and inflammatory disorders.
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Key Words
- ALDH1A2, aldehyde dehydrogenase 1 family member
- BAFF, B-cell activating factor
- CMTB, 4-chloro-α-(1-methylethyl)-N-2-thiazolylbenzeneacetamide
- DREADD, Designer Receptor Exclusively Activated by Designer Drug
- Enteroendocrine
- FFA2
- FFA3
- G protein–coupled receptors
- GLP-1, glucagon-like peptide 1
- GSIS, glucose-stimulated insulin secretion
- GTT, glucose tolerance test
- HFD, high-fat diet
- ILC3, type 3 innate lymphoid cell
- IgA, immunoglobulin A
- IgG, immunoglobulin G
- Immune cells
- KO, knock-out
- PA, (S)-2-(4-chlorophenyl)-3,3-dimethyl-N-(5-phenylthiazol-2-yl)butanamide
- PNS, peripheral nervous system
- PYY, peptide YY
- Pancreas
- SCA, small carboxylic acid
- SCFA, short-chain fatty acid
- SCG, superior cervical ganglion
- Short-chain fatty acids
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Affiliation(s)
- Daniele Bolognini
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Domonkos Dedeo
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Graeme Milligan
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
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23
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Free Fatty Acid Receptors 2 and 3 as Microbial Metabolite Sensors to Shape Host Health: Pharmacophysiological View. Biomedicines 2020; 8:biomedicines8060154. [PMID: 32521775 PMCID: PMC7344995 DOI: 10.3390/biomedicines8060154] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 05/30/2020] [Accepted: 06/01/2020] [Indexed: 12/13/2022] Open
Abstract
The role of the gut microbiome in human health is becoming apparent. The major functional impact of the gut microbiome is transmitted through the microbial metabolites that are produced in the gut and interact with host cells either in the local gut environment or are absorbed into circulation to impact distant cells/organs. Short-chain fatty acids (SCFAs) are the major microbial metabolites that are produced in the gut through the fermentation of non-digestible fibers. SCFAs are known to function through various mechanisms, however, their signaling through free fatty acid receptors 2 and 3 (FFAR2/3; type of G-coupled protein receptors) is a new therapeutic approach. FFAR2/3 are widely expressed in diverse cell types in human and mice, and function as sensors of SCFAs to change several physiological and cellular functions. FFAR2/3 modulate neurological signaling, energy metabolism, intestinal cellular homeostasis, immune response, and hormone synthesis. FFAR2/3 function through Gi and/or Gq signaling, that is mediated through specific structural features of SCFAs-FFAR2/3 bindings and modulating specific signaling pathway. In this review, we discuss the wide-spread expression and structural homologies between human and mice FFAR2/3, and their role in different human health conditions. This information can unlock opportunities to weigh the potential of FFAR2/3 as a drug target to prevent human diseases.
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24
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Ulven ER, Quon T, Sergeev E, Barki N, Brvar M, Hudson BD, Dutta P, Hansen AH, Bielefeldt LØ, Tobin AB, McKenzie CJ, Milligan G, Ulven T. Structure-Activity Relationship Studies of Tetrahydroquinolone Free Fatty Acid Receptor 3 Modulators. J Med Chem 2020; 63:3577-3595. [PMID: 32141297 PMCID: PMC7307922 DOI: 10.1021/acs.jmedchem.9b02036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Indexed: 12/27/2022]
Abstract
Free fatty acid receptor 3 (FFA3, previously GPR41) is activated by short-chain fatty acids, mediates health effects of the gut microbiota, and is a therapeutic target for metabolic and inflammatory diseases. The shortage of well-characterized tool compounds has however impeded progress. Herein, we report structure-activity relationship of an allosteric modulator series and characterization of physicochemical and pharmacokinetic properties of selected compounds, including previous and new tools. Two representatives, 57 (TUG-1907) and 63 (TUG-2015), showed improved solubility and preserved potency. Of these, 57, with EC50 = 145 nM and a solubility of 33 μM, showed high clearance in vivo but is a preferred tool in vitro. In contrast, 63, with EC50 = 162 nM and a solubility of 9 μM, showed lower clearance and seems better suited for in vivo studies. Using 57, we demonstrate for the first time that FFA3 activation leads to calcium mobilization in murine dorsal root ganglia.
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Affiliation(s)
- Elisabeth Rexen Ulven
- Department
of Drug Design and Pharmacology, University
of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
- Department
of Physics, Chemistry and Pharmacy, University
of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Tezz Quon
- Centre
for Translational Pharmacology, Institute of Molecular, Cell and Systems
Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, U.K.
| | - Eugenia Sergeev
- Centre
for Translational Pharmacology, Institute of Molecular, Cell and Systems
Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, U.K.
| | - Natasja Barki
- Centre
for Translational Pharmacology, Institute of Molecular, Cell and Systems
Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, U.K.
| | - Matjaz Brvar
- Department
of Physics, Chemistry and Pharmacy, University
of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Brian D. Hudson
- Centre
for Translational Pharmacology, Institute of Molecular, Cell and Systems
Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, U.K.
| | - Palash Dutta
- Department
of Drug Design and Pharmacology, University
of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Anders Højgaard Hansen
- Department
of Physics, Chemistry and Pharmacy, University
of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Line Ø. Bielefeldt
- Department
of Physics, Chemistry and Pharmacy, University
of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Andrew B. Tobin
- Centre
for Translational Pharmacology, Institute of Molecular, Cell and Systems
Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, U.K.
| | - Christine J. McKenzie
- Department
of Physics, Chemistry and Pharmacy, University
of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Graeme Milligan
- Centre
for Translational Pharmacology, Institute of Molecular, Cell and Systems
Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, U.K.
| | - Trond Ulven
- Department
of Drug Design and Pharmacology, University
of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Knauf C, Abot A, Wemelle E, Cani PD. Targeting the Enteric Nervous System to Treat Metabolic Disorders? "Enterosynes" as Therapeutic Gut Factors. Neuroendocrinology 2020; 110:139-146. [PMID: 31280267 DOI: 10.1159/000500602] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/28/2019] [Indexed: 11/19/2022]
Abstract
The gut-brain axis is of crucial importance for controlling glucose homeostasis. Alteration of this axis promotes the type 2 diabetes (T2D) phenotype (hyperglycaemia, insulin resistance). Recently, a new concept has emerged to demonstrate the crucial role of the enteric nervous system in the control of glycaemia via the hypothalamus. In diabetic patients and mice, modification of enteric neurons activity in the proximal part of the intestine generates a duodenal hyper-contractility that generates an aberrant message from the gut to the brain. In turn, the hypothalamus sends an aberrant efferent message that provokes a state of insulin resistance, which is characteristic of a T2D state. Targeting the enteric nervous system of the duodenum is now recognized as an innovative strategy for treatment of diabetes. By acting in the intestine, bioactive gut molecules that we called "enterosynes" can modulate the function of a specific type of neurons of the enteric nervous system to decrease the contraction of intestinal smooth muscle cells. Here, we focus on the origins of enterosynes (hormones, neurotransmitters, nutrients, microbiota, and immune factors), which could be considered therapeutic factors, and we describe their modes of action on enteric neurons. This unsuspected action of enterosynes is proposed for the treatment of T2D, but it could be applied for other therapeutic solutions that implicate communication between the gut and brain.
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Affiliation(s)
- Claude Knauf
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1220, Université Paul Sabatier, UPS, Institut de Recherche en Santé Digestive et Nutrition (IRSD), Toulouse, France,
- NeuroMicrobiota, European Associated Laboratory (EAL) INSERM, Toulouse, France,
| | - Anne Abot
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1220, Université Paul Sabatier, UPS, Institut de Recherche en Santé Digestive et Nutrition (IRSD), Toulouse, France
- NeuroMicrobiota, European Associated Laboratory (EAL) INSERM, Toulouse, France
| | - Eve Wemelle
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1220, Université Paul Sabatier, UPS, Institut de Recherche en Santé Digestive et Nutrition (IRSD), Toulouse, France
- NeuroMicrobiota, European Associated Laboratory (EAL) INSERM, Toulouse, France
| | - Patrice D Cani
- NeuroMicrobiota, European Associated Laboratory (EAL) INSERM, Toulouse, France
- UCLouvain, Université Catholique de Louvain, WELBIO - Walloon Excellence in Life Sciences and BIOtechnology, Louvain Drug Research Institute, Metabolism and Nutrition Research Group, Brussels, Belgium
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26
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Cryan JF, O'Riordan KJ, Cowan CSM, Sandhu KV, Bastiaanssen TFS, Boehme M, Codagnone MG, Cussotto S, Fulling C, Golubeva AV, Guzzetta KE, Jaggar M, Long-Smith CM, Lyte JM, Martin JA, Molinero-Perez A, Moloney G, Morelli E, Morillas E, O'Connor R, Cruz-Pereira JS, Peterson VL, Rea K, Ritz NL, Sherwin E, Spichak S, Teichman EM, van de Wouw M, Ventura-Silva AP, Wallace-Fitzsimons SE, Hyland N, Clarke G, Dinan TG. The Microbiota-Gut-Brain Axis. Physiol Rev 2019; 99:1877-2013. [DOI: 10.1152/physrev.00018.2018] [Citation(s) in RCA: 1243] [Impact Index Per Article: 248.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The importance of the gut-brain axis in maintaining homeostasis has long been appreciated. However, the past 15 yr have seen the emergence of the microbiota (the trillions of microorganisms within and on our bodies) as one of the key regulators of gut-brain function and has led to the appreciation of the importance of a distinct microbiota-gut-brain axis. This axis is gaining ever more traction in fields investigating the biological and physiological basis of psychiatric, neurodevelopmental, age-related, and neurodegenerative disorders. The microbiota and the brain communicate with each other via various routes including the immune system, tryptophan metabolism, the vagus nerve and the enteric nervous system, involving microbial metabolites such as short-chain fatty acids, branched chain amino acids, and peptidoglycans. Many factors can influence microbiota composition in early life, including infection, mode of birth delivery, use of antibiotic medications, the nature of nutritional provision, environmental stressors, and host genetics. At the other extreme of life, microbial diversity diminishes with aging. Stress, in particular, can significantly impact the microbiota-gut-brain axis at all stages of life. Much recent work has implicated the gut microbiota in many conditions including autism, anxiety, obesity, schizophrenia, Parkinson’s disease, and Alzheimer’s disease. Animal models have been paramount in linking the regulation of fundamental neural processes, such as neurogenesis and myelination, to microbiome activation of microglia. Moreover, translational human studies are ongoing and will greatly enhance the field. Future studies will focus on understanding the mechanisms underlying the microbiota-gut-brain axis and attempt to elucidate microbial-based intervention and therapeutic strategies for neuropsychiatric disorders.
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Affiliation(s)
- John F. Cryan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Kenneth J. O'Riordan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Caitlin S. M. Cowan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Kiran V. Sandhu
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Thomaz F. S. Bastiaanssen
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Marcus Boehme
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Martin G. Codagnone
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Sofia Cussotto
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Christine Fulling
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Anna V. Golubeva
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Katherine E. Guzzetta
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Minal Jaggar
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Caitriona M. Long-Smith
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Joshua M. Lyte
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Jason A. Martin
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Alicia Molinero-Perez
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Gerard Moloney
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Emanuela Morelli
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Enrique Morillas
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Rory O'Connor
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Joana S. Cruz-Pereira
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Veronica L. Peterson
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Kieran Rea
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Nathaniel L. Ritz
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Eoin Sherwin
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Simon Spichak
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Emily M. Teichman
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Marcel van de Wouw
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Ana Paula Ventura-Silva
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Shauna E. Wallace-Fitzsimons
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Niall Hyland
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Gerard Clarke
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
| | - Timothy G. Dinan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland
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Iwasaki M, Akiba Y, Kaunitz JD. Duodenal Chemosensing of Short-Chain Fatty Acids: Implications for GI Diseases. Curr Gastroenterol Rep 2019; 21:35. [PMID: 31289927 DOI: 10.1007/s11894-019-0702-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW Short-chain fatty acids (SCFAs), the main bacterial fermentation products in the hindgut of hindgut fermenters, are also present in the foregut lumen. We discuss the impact of SCFAs in the duodenal defense mechanisms and in the gastrointestinal (GI) pathogenesis. RECENT FINDINGS Luminal SCFAs augment the duodenal mucosal defenses via release of serotonin (5-HT) and glucagon-like peptide-2 (GLP-2) from enteroendocrine cells. Released GLP-2 protects the small intestinal mucosa from nonsteroidal anti-inflammatory drug-induced enteropathy. SCFAs are also rapidly absorbed via SCFA transporters and interact with afferent and myenteric nerves. Excessive SCFA signals with 5-HT3 receptor overactivation may be implicated in the pathogenesis of irritable bowel syndrome symptoms. SCFA production exhibits diurnal rhythms with host physiological responses, suggesting that oral SCFA treatment may adjust the GI clocks. SCFAs are not only a source of energy but also signaling molecules for the local regulation of the GI tract and systemic regulation via release of gut hormones. Targeting SCFA signals may be a novel therapeutic for GI diseases and metabolic syndrome.
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Affiliation(s)
- Mari Iwasaki
- West Los Angeles VAMC, 11301 Wilshire Blvd., Los Angeles, CA, 90073, USA
| | - Yasutada Akiba
- West Los Angeles VAMC, 11301 Wilshire Blvd., Los Angeles, CA, 90073, USA
- Department of Medicine, The David Geffen School of Medicine, University of California, Los Angeles, CA, 90073, USA
| | - Jonathan D Kaunitz
- West Los Angeles VAMC, 11301 Wilshire Blvd., Los Angeles, CA, 90073, USA.
- Department of Medicine, The David Geffen School of Medicine, University of California, Los Angeles, CA, 90073, USA.
- Department of Surgery, The David Geffen School of Medicine, University of California, Los Angeles, CA, 90073, USA.
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28
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Branched Short-Chain Fatty Acid Isovaleric Acid Causes Colonic Smooth Muscle Relaxation via cAMP/PKA Pathway. Dig Dis Sci 2019; 64:1171-1181. [PMID: 30560338 PMCID: PMC6499669 DOI: 10.1007/s10620-018-5417-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 12/06/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Isovaleric acid (IVA) is a 5-carbon branched-chain fatty acid present in fermented foods and produced in the colon by bacterial fermentation of leucine. We previously reported that the shorter, straight-chain fatty acids acetate, propionate and butyrate differentially affect colonic motility; however, the effect of branched-chain fatty acids on gut smooth muscle and motility is unknown. AIMS To determine the effect of IVA on contractility of colonic smooth muscle. METHODS Murine colonic segments were placed in a longitudinal orientation in organ baths in Krebs buffer and fastened to force transducers. Segments were contracted with acetylcholine (ACh), and the effects of IVA on ACh-induced contraction were measured in the absence and presence of tetrodotoxin (TTx) or inhibitors of nitric oxide synthase [L-N-nitroarginine (L-NNA)] or adenylate cyclase (SQ22536). The effect of IVA on ACh-induced contraction was also measured in isolated muscle cells in the presence or absence of SQ22536 or protein kinase A (PKA) inhibitor (H-89). Direct activation of PKA was measured in isolated muscle cells. RESULTS In colonic segments, ACh-induced contraction was inhibited by IVA in a concentration-dependent fashion; the IVA response was not affected by TTx or L-NNA but inhibited by SQ22536. Similarly, in isolated colonic muscle cells, ACh-induced contraction was inhibited by IVA in a concentration-dependent fashion and the effect blocked by SQ22536 and H-89. IVA also increased PKA activity in isolated smooth muscle cells. CONCLUSIONS The branched-chain fatty acid IVA acts directly on colonic smooth muscle and causes muscle relaxation via the PKA pathway.
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29
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Tough IR, Forbes S, Cox HM. Signaling of free fatty acid receptors 2 and 3 differs in colonic mucosa following selective agonism or coagonism by luminal propionate. Neurogastroenterol Motil 2018; 30:e13454. [PMID: 30136343 PMCID: PMC6282569 DOI: 10.1111/nmo.13454] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 06/20/2018] [Accepted: 07/25/2018] [Indexed: 01/05/2023]
Abstract
BACKGROUND Propionate exhibits affinity for free fatty acid receptor 2 (FFA2, formerly GPR43) and FFA3 (GPR41). These two G protein-coupled receptors (GPCRs) are expressed by enteroendocrine L cells that contain anorectic peptide YY (PYY) and glucagon-like peptide 1 (GLP-1), while FFA3 is also expressed by enteric neurons. Few studies have investigated the individual roles of FFA2 and FFA3 in propionate's gastrointestinal (GI) effects. Here, we compared FFA2, FFA3, and propionate mucosal responses utilizing selective ligands including an FFA3 antagonist, in mouse and human colonic mucosa. METHODS Vectorial ion transport was measured in native colonic preparations from normal mouse and human colon with intact submucosal innervation. Endogenous fecal pellet propulsion was monitored in colons isolated from wild-type (WT) and PYY-/- mice. KEY RESULTS FFA2 and FFA3 signaling differed significantly. FFA2 agonism involved endogenous L cell-derived PYY and was glucose dependent, while FFA3 agonism was independent of PYY and glucose, but required submucosal enteric neurons for activity. Tonic FFA3 activity was observed in mouse and human colon mucosa. Apical propionate responses were a combination of FFA2-PYY mediation and FFA3 neuronal GLP-1- and CGRP-dependent signaling in mouse ascending colon mucosa. Propionate also slowed WT and PYY-/- colonic transit, and this effect was blocked by a GLP-1 receptor antagonist. CONCLUSIONS & INFERENCES We conclude that luminal propionate costimulates FFA2 and FFA3 pathways, reducing anion secretion and slowing colonic motility; FFA2 via PYY mediation and FFA3 signaling by activation of enteric sensory neurons.
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Affiliation(s)
- Iain R. Tough
- King's College LondonWolfson Centre for Age‐Related Diseases, Institute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Sarah Forbes
- King's College LondonWolfson Centre for Age‐Related Diseases, Institute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Helen M. Cox
- King's College LondonWolfson Centre for Age‐Related Diseases, Institute of Psychiatry, Psychology & NeuroscienceLondonUK
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30
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Sharkey KA, Beck PL, McKay DM. Neuroimmunophysiology of the gut: advances and emerging concepts focusing on the epithelium. Nat Rev Gastroenterol Hepatol 2018; 15:765-784. [PMID: 30069036 DOI: 10.1038/s41575-018-0051-4] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The epithelial lining of the gastrointestinal tract serves as the interface for digestion and absorption of nutrients and water and as a defensive barrier. The defensive functions of the intestinal epithelium are remarkable considering that the gut lumen is home to trillions of resident bacteria, fungi and protozoa (collectively, the intestinal microbiota) that must be prevented from translocation across the epithelial barrier. Imbalances in the relationship between the intestinal microbiota and the host lead to the manifestation of diseases that range from disorders of motility and sensation (IBS) and intestinal inflammation (IBD) to behavioural and metabolic disorders, including autism and obesity. The latest discoveries shed light on the sophisticated intracellular, intercellular and interkingdom signalling mechanisms of host defence that involve epithelial and enteroendocrine cells, the enteric nervous system and the immune system. Together, they maintain homeostasis by integrating luminal signals, including those derived from the microbiota, to regulate the physiology of the gastrointestinal tract in health and disease. Therapeutic strategies are being developed that target these signalling systems to improve the resilience of the gut and treat the symptoms of gastrointestinal disease.
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Affiliation(s)
- Keith A Sharkey
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada. .,Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada. .,Gastrointestinal Research Group, University of Calgary, Calgary, Alberta, Canada. .,Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada.
| | - Paul L Beck
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.,Gastrointestinal Research Group, University of Calgary, Calgary, Alberta, Canada.,Inflammation Research Network, University of Calgary, Calgary, Alberta, Canada.,Division of Gastroenterology and Hepatology, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Derek M McKay
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.,Gastrointestinal Research Group, University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada.,Inflammation Research Network, University of Calgary, Calgary, Alberta, Canada
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31
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Selective tracking of FFAR3-expressing neurons supports receptor coupling to N-type calcium channels in mouse sympathetic neurons. Sci Rep 2018; 8:17379. [PMID: 30478340 PMCID: PMC6255804 DOI: 10.1038/s41598-018-35690-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 11/08/2018] [Indexed: 12/30/2022] Open
Abstract
Activation of short-chain free fatty acid receptors 3 (FFAR3) has been suggested to promote sympathetic outflow in postganglionic sympathetic neurons or hamper it by a negative coupling to N-type calcium (CaV2.2) channels. Heterogeneity of FFAR3 expression in sympathetic neurons, however, renders single neurons studies extremely time-consuming in wild-type mice. Previous studies demonstrated large variability of the degree of CaV2.2 channel inhibition by FFAR3 in a global population of rat sympathetic neurons. Therefore, we focused on a small subpopulation of mouse sympathetic neurons using an FFAR3 antibody and an Ffar3 reporter mouse to perform immunofluorescent and electrophysiological studies. Whole-cell patch-clamp recordings of identified FFAR3-expressing neurons from reporter mice revealed a 2.5-fold decrease in the CaV2.2-FFAR3 inhibitory coupling variability and 1.5-fold increase in the mean ICa2+ inhibition, when compared with unlabeled neurons from wild-type mice. Further, we found that the ablation of Ffar3 gene expression in two knockout mouse models led to a complete loss-of-function. Subpopulations of sympathetic neurons are associated with discrete functional pathways. However, little is known about the neural pathways of the FFAR3-expressing subpopulation. Our data indicate that FFAR3 is expressed primarily in neurons with a vasoconstrictor phenotype. Thus, fine-tuning of chemically-coded neurotransmitters may accomplish an adequate outcome.
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Abstract
PURPOSE OF REVIEW Luminal chemosensing is a term used to describe how small molecules in the gut lumen interact with the host through surface receptors or via transport into the submucosa. In this review, we have summarized recent advances of understanding luminal chemosensing in the gastroduodenal mucosa, with a particular emphasis on how chemosensing affects mucosal protective responses and the metabolic syndrome. RECENT FINDINGS In the past decade, data have supported the hypothesis that gut luminal chemosensing not only is important for the local or remote regulation of gut function but also contributes to the systemic regulation of metabolism, energy balance and food intake. We have provided examples of how luminal nutrients such as long-chain fatty acids (LCFAs), endogenous compounds such as bile acids, bacterial metabolites such as short-chain fatty acids (SCFAs) and bacterial components such as lipopolysaccharide (LPS) activate cognate receptors expressed on key effector cells such as enteroendocrine cells and inflammatory cells in order to profoundly affect organ function through the initiation or suppression of inflammatory pathways, altering gut barrier function and nutrient uptake, altering gut motility and visceral pain pathways, and preventing mucosal injury. SUMMARY These recent discoveries in this area have provided new possibilities for identifying novel molecular targets for the treatment of mucosal injury, metabolic disorders and abnormal visceral sensation. Understanding luminal chemosensory mechanisms may help to identify novel molecular targets for the treatment and prevention of mucosal injury, metabolic disorders and abnormal visceral sensation.
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33
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Kuwahara A, Kuwahara Y, Inui T, Marunaka Y. Regulation of Ion Transport in the Intestine by Free Fatty Acid Receptor 2 and 3: Possible Involvement of the Diffuse Chemosensory System. Int J Mol Sci 2018; 19:ijms19030735. [PMID: 29510573 PMCID: PMC5877596 DOI: 10.3390/ijms19030735] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 02/10/2018] [Accepted: 03/02/2018] [Indexed: 12/20/2022] Open
Abstract
The diffuse chemosensory system (DCS) is well developed in the apparatuses of endodermal origin like gastrointestinal (GI) tract. The primary function of the GI tract is the extraction of nutrients from the diet. Therefore, the GI tract must possess an efficient surveillance system that continuously monitors the luminal contents for beneficial or harmful compounds. Recent studies have shown that specialized cells in the intestinal lining can sense changes in the luminal content. The chemosensory cells in the GI tract belong to the DCS which consists of enteroendocrine and related cells. These cells initiate various important local and remote reflexes. Although neural and hormonal involvements in ion transport in the GI tract are well documented, involvement of the DCS in the regulation of intestinal ion transport is much less understood. Since activation of luminal chemosensory receptors is a primary signal that elicits changes in intestinal ion transport and motility and failure of the system causes dysfunctions in host homeostasis, as well as functional GI disorders, study of the regulation of GI function by the DCS has become increasingly important. This review discusses the role of the DCS in epithelial ion transport, with particular emphasis on the involvement of free fatty acid receptor 2 (FFA2) and free fatty acid receptor 3 (FFA3).
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Affiliation(s)
- Atsukazu Kuwahara
- Division of Molecular Cell Physiology, Kyoto prefectural University of Medicine, 465 Kajii-cho Kamigyo-ku, Kyoto 602-8566, Japan.
| | - Yuko Kuwahara
- Division of Molecular Cell Physiology, Kyoto prefectural University of Medicine, 465 Kajii-cho Kamigyo-ku, Kyoto 602-8566, Japan.
| | - Toshio Inui
- Saisei Mirai medical corporation, 6-14-17 Kinda, Moriguchi, Osaka 570-0011, Japan.
| | - Yoshinori Marunaka
- Division of Molecular Cell Physiology, Kyoto prefectural University of Medicine, 465 Kajii-cho Kamigyo-ku, Kyoto 602-8566, Japan.
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Kaji I, Akiba Y, Furuyama T, Adelson DW, Iwamoto K, Watanabe M, Kuwahara A, Kaunitz JD. Free fatty acid receptor 3 activation suppresses neurogenic motility in rat proximal colon. Neurogastroenterol Motil 2018; 30:10.1111/nmo.13157. [PMID: 28714277 PMCID: PMC5739952 DOI: 10.1111/nmo.13157] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 06/14/2017] [Indexed: 02/06/2023]
Abstract
BACKGROUND Short-chain fatty acids (SCFA) are microbial fermentation products absorbed by the colon. We recently reported that activation of the SCFA receptor termed free fatty acid receptor 3 (FFA3), expressed on cholinergic nerves, suppresses nicotinic acetylcholine receptor (nAChR)-mediated transepithelial anion secretion. This study aimed to clarify how activation of neurally expressed FFA3 affects colonic motor function. METHODS FFA3-expressing myenteric neurons were identified by immunostaining; contractions of isolated circular muscle strips obtained from rat proximal colon were measured by isometric transducers. The effect of FFA3 agonists on defecation in vivo was examined in an exogenous serotonin-induced defecation model. KEY RESULTS FFA3 immunoreactivity was located in nitrergic and cholinergic neurons in the myenteric plexus. In isolated circular muscle strips without mucosa and submucosa, the addition of nicotine (10 μM) or serotonin transiently relaxed the muscle through nitrergic neurons, whereas high concentrations of nicotine (100 μM) induced large-amplitude contractions that were mediated by cholinergic neurons. Pretreatment with FFA3 agonists inhibited nicotine- or serotonin-induced motility changes but had no effect on bethanechol-induced direct muscle contractions. The Gi/o inhibitor pertussis toxin reversed the inhibitory effect of an FFA3 agonist AR420626 on nicotine-evoked contractions, suggesting that FFA3 activation suppresses nAChR-mediated neural activity in myenteric neurons, consistent with an FFA3-mediated antisecretory effect. In conscious rats, exogenous serotonin increased the volume of fecal output, compared with the vehicle- or AR420626-treated groups. Pretreatment with AR420626 significantly suppressed serotonin-induced fecal output. CONCLUSION AND INFERENCES FFA3 is a promising target for the treatment of neurogenic diarrheal disorders by suppressing nAChR-mediated neural pathways.
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Affiliation(s)
- Izumi Kaji
- Department of Medicine, University of California Los Angeles,Greater Los Angeles VA Healthcare System
| | - Yasutada Akiba
- Department of Medicine, University of California Los Angeles,Greater Los Angeles VA Healthcare System
| | - Takafumi Furuyama
- Neuroethology & Bioengineering, Graduate School of Life & Medical Sciences, Doshisha University,Japan Society for the Promotion of Science
| | | | - Kenichi Iwamoto
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Masahiko Watanabe
- Department of Anatomy, Graduate School of Medicine, Hokkaido University
| | - Atsukazu Kuwahara
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Jonathan D. Kaunitz
- Department of Medicine, University of California Los Angeles,Department of Surgery, University of California Los Angeles,Greater Los Angeles VA Healthcare System
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Said H, Akiba Y, Narimatsu K, Maruta K, Kuri A, Iwamoto KI, Kuwahara A, Kaunitz JD. FFA3 Activation Stimulates Duodenal Bicarbonate Secretion and Prevents NSAID-Induced Enteropathy via the GLP-2 Pathway in Rats. Dig Dis Sci 2017; 62:1944-1952. [PMID: 28523577 PMCID: PMC5511769 DOI: 10.1007/s10620-017-4600-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/29/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Therapy with nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with enteropathy in humans and experimental animals, a cause of considerable morbidity. Unlike foregut NSAID-associated mucosal lesions, most treatments for this condition are of little efficacy. We propose that the endogenously released intestinotrophic hormone glucagon-like peptide-2 (GLP-2) prevents the development of NSAID-induced enteropathy. Since the short-chain fatty acid receptor FFA3 is expressed on enteroendocrine L cells and on enteric nerves in the gastrointestinal tract, we further hypothesized that activation of FFA3 on L cells protects the mucosa from injury via GLP-2 release with enhanced duodenal HCO3- secretion. We thus investigated the effects of synthetic selective FFA3 agonists with consequent GLP-2 release on NSAID-induced enteropathy. METHODS We measured duodenal HCO3- secretion in isoflurane-anesthetized rats in a duodenal loop perfused with the selective FFA3 agonists MQC or AR420626 (AR) while measuring released GLP-2 in the portal vein (PV). Intestinal injury was produced by indomethacin (IND, 10 mg/kg, sc) with or without MQC (1-10 mg/kg, ig) or AR (0.01-0.1 mg/kg, ig or ip) treatment. RESULTS Luminal perfusion with MQC or AR (0.1-10 µM) dose-dependently augmented duodenal HCO3- secretion accompanied by increased GLP-2 concentrations in the PV. The effect of FFA3 agonists was inhibited by co-perfusion of the selective FFA3 antagonist CF3-MQC (30 µM). AR-induced augmented HCO3- secretion was reduced by iv injection of the GLP-2 receptor antagonist GLP-2(3-33) (3 nmol/kg), or by pretreatment with the cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor CFTRinh-172 (1 mg/kg, ip). IND-induced small intestinal ulcers were dose-dependently inhibited by intragastric administration of MQC or AR. GLP-2(3-33) (1 mg/kg, ip) or CF3-MQC (1 mg/kg, ig) reversed AR-associated reduction in IND-induced enteropathy. In contrast, ip injection of AR had no effect on enteropathy. CONCLUSION These results suggest that luminal FFA3 activation enhances mucosal defenses and prevents NSAID-induced enteropathy via the GLP-2 pathway. The selective FFA3 agonist may be a potential therapeutic candidate for NSAID-induced enteropathy.
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Affiliation(s)
- Hyder Said
- College of Arts and Sciences, University of California, Los Angeles, CA, USA
| | - Yasutada Akiba
- Greater Los Angeles Veterans Affairs Healthcare System, 11301 Wilshire Boulevard, Bldg 115, Suite 217, Los Angeles, CA, 90073, USA
- Department of Medicine, University of California Los Angeles, School of Medicine, Los Angeles, CA, USA
- Brentwood Biomedical Research Institute, Los Angeles, CA, USA
| | - Kazuyuki Narimatsu
- Department of Medicine, University of California Los Angeles, School of Medicine, Los Angeles, CA, USA
| | - Koji Maruta
- Department of Medicine, University of California Los Angeles, School of Medicine, Los Angeles, CA, USA
| | - Ayaka Kuri
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan
| | - Ken-Ichi Iwamoto
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan
| | - Atsukazu Kuwahara
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan
| | - Jonathan D Kaunitz
- Greater Los Angeles Veterans Affairs Healthcare System, 11301 Wilshire Boulevard, Bldg 115, Suite 217, Los Angeles, CA, 90073, USA.
- Department of Medicine, University of California Los Angeles, School of Medicine, Los Angeles, CA, USA.
- Brentwood Biomedical Research Institute, Los Angeles, CA, USA.
- Department of Surgery, University of California Los Angeles, School of Medicine, Los Angeles, CA, USA.
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Wan Saudi WS, Sjöblom M. Short-chain fatty acids augment rat duodenal mucosal barrier function. Exp Physiol 2017; 102:791-803. [PMID: 28436589 DOI: 10.1113/ep086110] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 04/16/2017] [Indexed: 02/06/2023]
Abstract
NEW FINDINGS What is the central question of this study? Small intestinal epithelium is exposed to high concentrations of short-chain fatty acids (SCFAs), but their role in regulating intestinal mucosal barrier function and motility is not fully understood. What is the main finding and its importance? By perfusing the duodenal segment in anaesthetized rats, we show that acetate and propionate significantly decrease mucosal paracellular permeability and transepithelial net fluid flux and increase mucosal bicarbonate secretion. Likewise, SCFAs administered i.v. decrease mucosal permeability but decrease bicarbonate secretion. Altered luminal chemosensing or aberrant signalling in response to SCFAs might contribute to symptoms observed in patients with suppressed mucosal barrier function. Short-chain fatty acids (SCFAs) are produced by bacterial fermentation in the large intestine, particularly from diets containing fibres and carbohydrates. The small intestinal epithelium is exposed to SCFAs derived mainly from oral bacteria or food supplementation. Although luminal nutrients are important in regulation of intestinal functions, the role of SCFAs in regulation of small intestinal mucosal barrier function and motility has not been fully described. The aim of the present study was to elucidate the effects of acetate and propionate on duodenal mucosal barrier function and motility. Rats were anaesthetized with thiobarbiturate, and a 30 mm segment of proximal duodenum with an intact blood supply was perfused. The effects on duodenal bicarbonate secretion, blood-to-lumen clearance of 51 Cr-EDTA, motility and transepithelial net fluid flux were investigated. Perfusion of the duodenum with acetate or propionate significantly decreased mucosal paracellular permeability and transepithelial net fluid flux and significantly increased bicarbonate secretion. Acetate or propionate administered as an i.v. infusion decreased the mucosal paracellular permeability, but significantly decreased bicarbonate secretion. Luminal SCFAs changed the duodenal motility pattern from migrating motor complexes to fed patterns. Systemic administration of glucagon-like peptide-2 induced increases in both bicarbonate secretion and net fluid absorption, but did not change motility. Glucagon-like peptide-2 infusion during luminal perfusion of SCFAs significantly reduced the motility. In conclusion, SCFAs decreased duodenal paracellular permeability and net fluid flux. Short-chain fatty acids induced opposite effects on bicarbonate secretion after luminal and i.v. administration. Presence of SCFAs in the lumen induces fed motility patterns. Altered luminal chemosensing and aberrant signalling in response to SCFAs might contribute to symptoms observed in patients with suppressed barrier function.
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Affiliation(s)
- Wan Salman Wan Saudi
- Division of Gastrointestinal Physiology, Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Markus Sjöblom
- Division of Gastrointestinal Physiology, Department of Neuroscience, Uppsala University, Uppsala, Sweden
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Fung C, Boesmans W, Cirillo C, Foong JPP, Bornstein JC, Vanden Berghe P. VPAC Receptor Subtypes Tune Purinergic Neuron-to-Glia Communication in the Murine Submucosal Plexus. Front Cell Neurosci 2017; 11:118. [PMID: 28487635 PMCID: PMC5403822 DOI: 10.3389/fncel.2017.00118] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 04/10/2017] [Indexed: 12/20/2022] Open
Abstract
The enteric nervous system (ENS) situated within the gastrointestinal tract comprises an intricate network of neurons and glia which together regulate intestinal function. The exact neuro-glial circuitry and the signaling molecules involved are yet to be fully elucidated. Vasoactive intestinal peptide (VIP) is one of the main neurotransmitters in the gut, and is important for regulating intestinal secretion and motility. However, the role of VIP and its VPAC receptors within the enteric circuitry is not well understood. We investigated this in the submucosal plexus of mouse jejunum using calcium (Ca2+)-imaging. Local VIP application induced Ca2+-transients primarily in neurons and these were inhibited by VPAC1- and VPAC2-antagonists (PG 99-269 and PG 99-465 respectively). These VIP-evoked neural Ca2+-transients were also inhibited by tetrodotoxin (TTX), indicating that they were secondary to action potential generation. Surprisingly, VIP induced Ca2+-transients in glia in the presence of the VPAC2 antagonist. Further, selective VPAC1 receptor activation with the agonist ([K15, R16, L27]VIP(1-7)/GRF(8-27)) predominantly evoked glial responses. However, VPAC1-immunoreactivity did not colocalize with the glial marker glial fibrillary acidic protein (GFAP). Rather, VPAC1 expression was found on cholinergic submucosal neurons and nerve fibers. This suggests that glial responses observed were secondary to neuronal activation. Trains of electrical stimuli were applied to fiber tracts to induce endogenous VIP release. Delayed glial responses were evoked when the VPAC2 antagonist was present. These findings support the presence of an intrinsic VIP/VPAC-initiated neuron-to-glia signaling pathway. VPAC1 agonist-evoked glial responses were inhibited by purinergic antagonists (PPADS and MRS2179), thus demonstrating the involvement of P2Y1 receptors. Collectively, we showed that neurally-released VIP can activate neurons expressing VPAC1 and/or VPAC2 receptors to modulate purine-release onto glia. Selective VPAC1 activation evokes a glial response, whereas VPAC2 receptors may act to inhibit this response. Thus, we identified a component of an enteric neuron-glia circuit that is fine-tuned by endogenous VIP acting through VPAC1- and VPAC2-mediated pathways.
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Affiliation(s)
- Candice Fung
- Department of Physiology, The University of MelbourneParkville, VIC, Australia.,Laboratory for Enteric Neuroscience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), KU LeuvenLeuven, Belgium
| | - Werend Boesmans
- Laboratory for Enteric Neuroscience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), KU LeuvenLeuven, Belgium
| | - Carla Cirillo
- Laboratory for Enteric Neuroscience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), KU LeuvenLeuven, Belgium
| | - Jaime P P Foong
- Department of Physiology, The University of MelbourneParkville, VIC, Australia
| | - Joel C Bornstein
- Department of Physiology, The University of MelbourneParkville, VIC, Australia
| | - Pieter Vanden Berghe
- Laboratory for Enteric Neuroscience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), KU LeuvenLeuven, Belgium
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DUBOC H, TOLSTANOVA G, YUAN PQ, WU V, KAJI I, BIRAUD M, AKIBA Y, KAUNITZ J, MILLION M, TACHE Y, LARAUCHE M. Reduction of epithelial secretion in male rat distal colonic mucosa by bile acid receptor TGR5 agonist, INT-777: role of submucosal neurons. Neurogastroenterol Motil 2016; 28:1663-1676. [PMID: 27259385 PMCID: PMC5083223 DOI: 10.1111/nmo.12866] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 04/28/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND Recent evidence from rat neuron-free mucosa study suggests that the membrane bile acid receptor TGR5 decreases colonic secretion under basal and stimulated conditions. As submucosal neurons are key players in secretory processes and highly express TGR5, we investigated their role in TGR5 agonist-induced inhibition of secretion and the pathways recruited. METHODS TGR5 expression and localization were assessed in rat proximal (pC) and distal (dC) colon by qPCR and immunohistochemistry with double labeling for cholinergic neurons in whole-mount preparations. The influence of a selective (INT-777) or weak (ursodeoxycholic acid, UDCA) TGR5 agonist on colonic secretion was assessed in Ussing chambers, in dC preparation removing seromuscular ± submucosal tissues, in the presence of different inhibitors of secretion pathways. KEY RESULTS TGR5 mRNA is expressed in full thickness dC and pC and immunoreactivity is located in colonocytes and pChAT-positive neurons. Addition of INT-777, and less potently UDCA, decreased colonic secretion in seromuscular stripped dC by -58.17± 2.6%. INT-777 effect on basal secretion was reduced in neuron-free and TTX-treated mucosal-submucosal preparations. Atropine, hexamethonium, indomethacin, and L-NAME all reduced significantly INT-777's inhibitory effect while the 5-HT4 antagonist, RS-39604, and lidocaine abolished it. INT-777 inhibited stimulated colonic secretion induced by nicotine, but not cisapride, carbachol or PGE2. CONCLUSIONS & INFERENCES TGR5 activation inhibits basal and stimulated distal colonic secretion in rats by acting directly on epithelial cells and also inhibiting submucosal neurons. This could represent a counter-regulatory mechanism, at the submucosal level, of the known prosecretory effect of bile acids in the colon.
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Affiliation(s)
- Henri DUBOC
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA,DHU UNITY, Inserm UMR 1149, and Louis Mourier Hospital, Department of Gastroenterology and Hepatology, AP-HP, University Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Ganna TOLSTANOVA
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA,Educational-Scientific Center “Institute of Biology” Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
| | - Pu-Qing YUAN
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - Vincent WU
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - Izumi KAJI
- Department of Medicine, School of Medicine, UCLA,Brentwood Biomedical Research Institute, Los Angeles, California, USA
| | - Mandy BIRAUD
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - Yasutada AKIBA
- VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA,Department of Medicine, School of Medicine, UCLA,Brentwood Biomedical Research Institute, Los Angeles, California, USA
| | - Jonathan KAUNITZ
- VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA,Department of Medicine, School of Medicine, UCLA,Department of Surgery, School of Medicine, UCLA,Brentwood Biomedical Research Institute, Los Angeles, California, USA
| | - Mulugeta MILLION
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - Yvette TACHE
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - Muriel LARAUCHE
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Division of Digestive Diseases, David Geffen School of Medicine at UCLA,VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
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