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Chrysant SG. The role of gut microbiota in the development of salt-sensitive hypertension and the possible preventive effect of exercise. Expert Rev Cardiovasc Ther 2024; 22:265-271. [PMID: 38823009 DOI: 10.1080/14779072.2024.2364031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 05/31/2024] [Indexed: 06/03/2024]
Abstract
INTRODUCTION The aim of the present study is to analyze the data indicating an association between high salt intake and the gastrointestinal microbiota in the development of salt-sensitive hypertension in animals and men. It is also, to discuss the preventive effects of exercise on gut-induced hypertension by favorably modifying the composition of gut microbiota. AREAS COVERED Salt sensitivity is quite common, accounting for 30%-60% in hypertensive subjects. Recently, a novel cause for salt-sensitive hypertension has been discovered through the action of gut microbiota by the secretion of several hormones and the action of short chain fatty acids (SCFAs). In addition, recent studies indicate that exercise might favorably modify the adverse effects of gut microbiota regarding their effects on BP. To identify the role of gut microbiota on the incidence of hypertension and CVD and the beneficial effect of exercise, a Medline search of the English literature was conducted between 2018 and 2023 and 42 pertinent papers were selected. EXPERT OPINION The analysis of data from the selected papers disclosed that the gut microbiota contribute significantly to the development of salt-sensitive hypertension and that exercise modifies their gut composition and ameliorates their adverse effects on BP.
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Affiliation(s)
- Steven G Chrysant
- Cardiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
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2
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Tough IR, Lund ML, Patel BA, Schwartz TW, Cox HM. Paracrine relationship between incretin hormones and endogenous 5-hydroxytryptamine in the small and large intestine. Neurogastroenterol Motil 2023; 35:e14589. [PMID: 37010838 PMCID: PMC10909488 DOI: 10.1111/nmo.14589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 02/13/2023] [Accepted: 03/21/2023] [Indexed: 04/04/2023]
Abstract
BACKGROUND Enterochromaffin (EC) cell-derived 5-hydroxytryptamine (5-HT) is a mediator of toxin-induced reflexes, initiating emesis via vagal and central 5-HT3 receptors. The amine is also involved in gastrointestinal (GI) reflexes that are prosecretory and promotile, and recently 5-HT's roles in chemosensation in the distal bowel have been described. We set out to establish the efficacy of 5-HT signaling, local 5-HT levels and pharmacology in discrete regions of the mouse small and large intestine. We also investigated the inter-relationships between incretin hormones, glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP) and endogenous 5-HT in mucosal and motility assays. METHODS Adult mouse GI mucosae were mounted in Ussing chambers and area-specific studies were performed to establish the 5-HT3 and 5-HT4 pharmacology, the sidedness of responses, and the inter-relationships between incretins and endogenous 5-HT. Natural fecal pellet transit in vitro and full-length GI transit in vivo were also measured. KEY RESULTS We observed the greatest level of tonic and exogenous 5-HT-induced ion transport and highest levels of 5-HT in ascending colon mucosa. Here both 5-HT3 and 5-HT4 receptors were involved but elsewhere in the GI tract epithelial basolateral 5-HT4 receptors mediate 5-HT's prosecretory effect. Exendin-4 and GIP induced 5-HT release in the ascending colon, while L cell-derived PYY also contributed to GIP mucosal effects in the descending colon. Both peptides slowed colonic transit. CONCLUSIONS & INFERENCES We provide functional evidence for paracrine interplay between 5-HT, GLP-1 and GIP, particularly in the colonic mucosal region. Basolateral epithelial 5-HT4 receptors mediated both 5-HT and incretin mucosal responses in healthy colon.
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Affiliation(s)
- Iain R. Tough
- Wolfson Centre for Age‐Related Diseases, Institute of Psychology, Psychiatry and NeuroscienceKing's College LondonHodgkin Building, Guy's CampusLondonSE1 1ULUK
| | - Mari L. Lund
- The Novo Nordisk Foundation Centre for Basic Metabolic Research, Section for Metabolic Receptology and EnteroendocrinologyUniversity of CopenhagenCopenhagenDK‐2200Denmark
- Present address:
Chr. Hansen A/S, Human Health ResearchHoersholmDK‐2970Denmark
| | - Bhavik A. Patel
- Centre for Stress and Age‐Related Diseases, School of Applied SciencesUniversity of BrightonBrightonUK
| | - Thue W. Schwartz
- The Novo Nordisk Foundation Centre for Basic Metabolic Research, Section for Metabolic Receptology and EnteroendocrinologyUniversity of CopenhagenCopenhagenDK‐2200Denmark
| | - Helen M. Cox
- Wolfson Centre for Age‐Related Diseases, Institute of Psychology, Psychiatry and NeuroscienceKing's College LondonHodgkin Building, Guy's CampusLondonSE1 1ULUK
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Lo SW, Segal JP, Lubel JS, Garg M. What do we know about the renin angiotensin system and inflammatory bowel disease? Expert Opin Ther Targets 2022; 26:897-909. [PMID: 36484415 DOI: 10.1080/14728222.2022.2157261] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION The renin-angiotensin system (RAS) is an important homeostatic pathway, with emerging evidence for the impact of its components on inflammation and fibrosis in gastrointestinal tissues. This review aims to review current knowledge of the physiological mechanism of RAS in inflammatory bowel disease (IBD), and potential therapeutic implications. AREAS COVERED An extensive online literature review including Pubmed, Medline, and Google Scholar was undertaken. Discussion on the components of the RAS, localization, and physiological functions in the gastrointestinal tract, preclinical, and clinical data in IBD, and the relation with SARS-Cov-2 are covered in this review. EXPERT OPINION RAS inhibition may have a role as anti-fibrotic adjunct therapy. Targeting the local gastrointestinal RAS with novel modes of delivery may be a target for future therapeutics for IBD, given the widespread availability and safety of current options as utilized in other diseases. Further insight into the mechanism and downstream effects of gastrointestinal ACE2 may lead to a better understanding of the pathogenesis of IBD.
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Affiliation(s)
- Sheng Wei Lo
- Department of Gastroenterology, Northern Hospital, 3076 Melbourne, Australia
| | - Jonathan P Segal
- Department of Gastroenterology, Northern Hospital, 3076 Melbourne, Australia.,Department of Medicine, University of Melbourne, Australia
| | - John S Lubel
- Department of Gastroenterology, Northern Hospital, 3076 Melbourne, Australia.,Department of Medicine, Monash University
| | - Mayur Garg
- Department of Gastroenterology, Northern Hospital, 3076 Melbourne, Australia.,Department of Medicine, University of Melbourne, Australia
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Esser N, Schmidt C, Barrow BM, Cronic L, Hackney DJ, Mongovin SM, Hogan MF, Templin AT, Castillo JJ, Hull RL, Zraika S. Insulinotropic Effects of Neprilysin and/or Angiotensin Receptor Inhibition in Mice. Front Endocrinol (Lausanne) 2022; 13:888867. [PMID: 35733766 PMCID: PMC9207331 DOI: 10.3389/fendo.2022.888867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 04/27/2022] [Indexed: 11/13/2022] Open
Abstract
Treatment of heart failure with the angiotensin receptor-neprilysin inhibitor sacubitril/valsartan improved glycemic control in individuals with type 2 diabetes. The relative contribution of neprilysin inhibition versus angiotensin II receptor antagonism to this glycemic benefit remains unknown. Thus, we sought to determine the relative effects of the neprilysin inhibitor sacubitril versus the angiotensin II receptor blocker valsartan on beta-cell function and glucose homeostasis in a mouse model of reduced first-phase insulin secretion, and whether any beneficial effects are additive/synergistic when combined in sacubitril/valsartan. High fat-fed C57BL/6J mice treated with low-dose streptozotocin (or vehicle) were followed for eight weeks on high fat diet alone or supplemented with sacubitril, valsartan or sacubitril/valsartan. Body weight and fed glucose levels were assessed weekly. At the end of the treatment period, insulin release in response to intravenous glucose, insulin sensitivity, and beta-cell mass were determined. Sacubitril and valsartan, but not sacubitril/valsartan, lowered fasting and fed glucose levels and increased insulin release in diabetic mice. None of the drugs altered insulin sensitivity or beta-cell mass, but all reduced body weight gain. Effects of the drugs on insulin release were reproduced in angiotensin II-treated islets from lean C57BL/6J mice, suggesting the insulin response to each of the drugs is due to a direct effect on islets and mechanisms therein. In summary, sacubitril and valsartan each exert beneficial insulinotropic, glycemic and weight-reducing effects in obese and/or diabetic mice when administered alone; however, when combined, mechanisms within the islet contribute to their inability to enhance insulin release.
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Affiliation(s)
- Nathalie Esser
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
- Division of Metabolism, Endocrinology & Nutrition, Department of Medicine, University of Washington, Seattle, WA, United States
- Laboratory of Immunometabolism and Nutrition, GIGA Infection, Immunity and Inflammation, University of Liège, Liège, Belgium
| | - Christine Schmidt
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
| | - Breanne M. Barrow
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
| | - Laura Cronic
- Division of Metabolism, Endocrinology & Nutrition, Department of Medicine, University of Washington, Seattle, WA, United States
| | - Daryl J. Hackney
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
| | - Stephen M. Mongovin
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
| | - Meghan F. Hogan
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
- Division of Metabolism, Endocrinology & Nutrition, Department of Medicine, University of Washington, Seattle, WA, United States
| | - Andrew T. Templin
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
- Division of Metabolism, Endocrinology & Nutrition, Department of Medicine, University of Washington, Seattle, WA, United States
| | - Joseph J. Castillo
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
- Division of Metabolism, Endocrinology & Nutrition, Department of Medicine, University of Washington, Seattle, WA, United States
| | - Rebecca L. Hull
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
- Division of Metabolism, Endocrinology & Nutrition, Department of Medicine, University of Washington, Seattle, WA, United States
| | - Sakeneh Zraika
- Research Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
- Division of Metabolism, Endocrinology & Nutrition, Department of Medicine, University of Washington, Seattle, WA, United States
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Abstract
The enteroendocrine system coordinates the physiological response to food intake by regulating rates of digestion, nutrient absorption, insulin secretion, satiation and satiety. Gut hormones with important anorexigenic and/or insulinotropic roles include glucagon-like peptide 1 (GLP-1), peptide YY (PYY3-36), cholecystokinin (CCK) and glucose-dependent insulinotropic peptide (GIP). High BMI or obesogenic diets do not markedly disrupt this enteroendocrine system, which represents a critical target for inducing weight loss and treating co-morbidities in individuals with obesity.
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6
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Yang M, Reimann F, Gribble FM. Chemosensing in enteroendocrine cells: mechanisms and therapeutic opportunities. Curr Opin Endocrinol Diabetes Obes 2021; 28:222-231. [PMID: 33449572 DOI: 10.1097/med.0000000000000614] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE OF REVIEW Enteroendocrine cells (EECs) are scattered chemosensory cells in the intestinal epithelium that release hormones with a wide range of actions on intestinal function, food intake and glucose homeostasis. The mechanisms by which gut hormones are secreted postprandially, or altered by antidiabetic agents and surgical interventions are of considerable interest for future therapeutic development. RECENT FINDINGS EECs are electrically excitable and express a repertoire of G-protein coupled receptors that sense nutrient and nonnutrient stimuli, coupled to intracellular Ca2+ and cyclic adenosine monophosphate. Our knowledge of EEC function, previously developed using mouse models, has recently been extended to human cells. Gut hormone release in humans is enhanced by bariatric surgery, as well as by some antidiabetic agents including sodium-coupled glucose transporter inhibitors and metformin. SUMMARY EECs are important potential therapeutic targets. A better understanding of their chemosensory mechanisms will enhance the development of new therapeutic strategies to treat metabolic and gastrointestinal diseases.
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Affiliation(s)
- Ming Yang
- University of Cambridge, Institute of Metabolic Science and MRC Metabolic Diseases Unit, Addenbrooke's Hospital, Cambridge, UK
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Abstract
Glucagon like peptide-1 (GLP-1), a peptide hormone from the intestinal tract, plays a central role in the coordination of postprandial glucose homeostasis through actions on insulin secretion, food intake and gut motility. GLP-1 forms the basis for a variety of current drugs for the treatment of type 2 diabetes and obesity, as well as new agents currently being developed. Here, we provide a concise overview of the core physiology of GLP-1 secretion and action, and the role of the peptide in human health, disease and therapeutics.
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Affiliation(s)
- Fiona M Gribble
- Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
| | - Frank Reimann
- Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
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8
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Kuhre RE, Deacon CF, Holst JJ, Petersen N. What Is an L-Cell and How Do We Study the Secretory Mechanisms of the L-Cell? Front Endocrinol (Lausanne) 2021; 12:694284. [PMID: 34168620 PMCID: PMC8218725 DOI: 10.3389/fendo.2021.694284] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 05/11/2021] [Indexed: 12/14/2022] Open
Abstract
Synthetic glucagon-like peptide-1 (GLP-1) analogues are effective anti-obesity and anti-diabetes drugs. The beneficial actions of GLP-1 go far beyond insulin secretion and appetite, and include cardiovascular benefits and possibly also beneficial effects in neurodegenerative diseases. Considerable reserves of GLP-1 are stored in intestinal endocrine cells that potentially might be mobilized by pharmacological means to improve the body's metabolic state. In recognition of this, the interest in understanding basic L-cell physiology and the mechanisms controlling GLP-1 secretion, has increased considerably. With a view to home in on what an L-cell is, we here present an overview of available data on L-cell development, L-cell peptide expression profiles, peptide production and secretory patterns of L-cells from different parts of the gut. We conclude that L-cells differ markedly depending on their anatomical location, and that the traditional definition of L-cells as a homogeneous population of cells that only produce GLP-1, GLP-2, glicentin and oxyntomodulin is no longer tenable. We suggest to sub-classify L-cells based on their differential peptide contents as well as their differential expression of nutrient sensors, which ultimately determine the secretory responses to different stimuli. A second purpose of this review is to describe and discuss the most frequently used experimental models for functional L-cell studies, highlighting their benefits and limitations. We conclude that no experimental model is perfect and that a comprehensive understanding must be built on results from a combination of models.
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Affiliation(s)
- Rune E. Kuhre
- Department of Obesity Pharmacology, Novo Nordisk, Måløv, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Rune E. Kuhre, ;
| | - Carolyn F. Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
- School of Biomedical Sciences, Ulster University, Coleraine, United Kingdom
| | - Jens J. Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
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9
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Akhtar S, Benter IF, Danjuma MI, Doi SAR, Hasan SS, Habib AM. Pharmacotherapy in COVID-19 patients: a review of ACE2-raising drugs and their clinical safety. J Drug Target 2020; 28:683-699. [PMID: 32700580 DOI: 10.1080/1061186x.2020.1797754] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The COVID-19 pandemic is caused by the severe acute-respiratory-syndrome-coronavirus-2 that uses ACE2 as its receptor. Drugs that raise serum/tissue ACE2 levels include ACE inhibitors (ACEIs) and angiotensin-II receptor blockers (ARBs) that are commonly used in patients with hypertension, cardiovascular disease and/or diabetes. These comorbidities have adverse outcomes in COVID-19 patients that might result from pharmacotherapy. Increasing ACE2 could potentially increase the risk of infection, severity or mortality in COVID-19 or it might be protective as it forms angiotensin-(1-7) which exhibits anti-inflammatory/anti-oxidative effects and prevents diabetes- and/or hypertension-induced end-organ damage. Thus, there existed clinical uncertainty. Here, we review studies implicating 15 classes of drugs in increasing ACE2 levels in vivo and the available literature on the clinical safety of these drugs in COVID-19 patients. Further, in a re-analysis of clinical data from a meta-analysis of 9 studies, we show that ACEIs/ARBs usage was not associated with an increased risk of all-cause mortality. Literature suggests that ACEIs/ARBs usage generally appears to be clinically safe though their use in severe COVID-19 patients might increase the risk of acute renal injury. For definitive clarity, further clinical and mechanistic studies are needed in assessing the safety of all classes of ACE2 raising medications.
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Affiliation(s)
- Saghir Akhtar
- College of Medicine, QU Health, Qatar University, Doha, Qatar
| | - Ibrahim F Benter
- Faculty of Medicine, Eastern Mediterranean University, Famagusta, North Cyprus
| | - Mohammed I Danjuma
- College of Medicine, QU Health, Qatar University, Doha, Qatar.,Division of Internal Medicine, Hamad Medical Corporation Hospital, Doha, Qatar
| | - Suhail A R Doi
- College of Medicine, QU Health, Qatar University, Doha, Qatar
| | - Syed S Hasan
- School of Applied Sciences, University of Huddersfield, Huddersfield, UK
| | - Abdella M Habib
- College of Medicine, QU Health, Qatar University, Doha, Qatar
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10
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Lewis JE, Miedzybrodzka EL, Foreman RE, Woodward ORM, Kay RG, Goldspink DA, Gribble FM, Reimann F. Selective stimulation of colonic L cells improves metabolic outcomes in mice. Diabetologia 2020; 63:1396-1407. [PMID: 32342115 PMCID: PMC7286941 DOI: 10.1007/s00125-020-05149-w] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 03/03/2020] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS Insulin-like peptide-5 (INSL5) is found only in distal colonic L cells, which co-express glucagon-like peptide-1 (GLP-1) and peptide YY (PYY). GLP-1 is a well-known insulin secretagogue, and GLP-1 and PYY are anorexigenic, whereas INSL5 is considered orexigenic. We aimed to clarify the metabolic impact of selective stimulation of distal colonic L cells in mice. METHODS Insl5 promoter-driven expression of Gq-coupled Designer Receptor Exclusively Activated by Designer Drugs (DREADD) was employed to activate distal colonic L cells (LdistalDq). IPGTT and food intake were assessed with and without DREADD activation. RESULTS LdistalDq cell stimulation with clozapine N-oxide (CNO; 0.3 mg/kg i.p.) increased plasma GLP-1 and PYY (2.67- and 3.31-fold, respectively); INSL5 was not measurable in plasma but was co-secreted with GLP-1 and PYY in vitro. IPGTT (2 g/kg body weight) revealed significantly improved glucose tolerance following CNO injection. CNO-treated mice also exhibited reduced food intake and body weight after 24 h, and increased defecation, the latter being sensitive to 5-hydroxytryptamine (5-HT) receptor 3 inhibition. Pre-treatment with a GLP1 receptor-blocking antibody neutralised the CNO-dependent improvement in glucose tolerance but did not affect the reduction in food intake, and an independent group of animals pair-fed to the CNO-treatment group demonstrated attenuated weight loss. Pre-treatment with JNJ-31020028, a neuropeptide Y receptor type 2 antagonist, abolished the CNO-dependent effect on food intake. Assessment of whole body physiology in metabolic cages revealed LdistalDq cell stimulation increased energy expenditure and increased activity. Acute CNO-induced food intake and glucose homeostasis outcomes were maintained after 2 weeks on a high-fat diet. CONCLUSIONS/INTERPRETATION This proof-of-concept study demonstrates that selective distal colonic L cell stimulation has beneficial metabolic outcomes. Graphical abstract.
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Affiliation(s)
- Jo E Lewis
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK
| | - Emily L Miedzybrodzka
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK
| | - Rachel E Foreman
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK
| | - Orla R M Woodward
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK
| | - Richard G Kay
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK
| | - Deborah A Goldspink
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK
| | - Fiona M Gribble
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK.
| | - Frank Reimann
- Wellcome Trust-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, Cambridge, CB2 OQQ, UK.
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11
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Goldspink DA, Lu VB, Miedzybrodzka EL, Smith CA, Foreman RE, Billing LJ, Kay RG, Reimann F, Gribble FM. Labeling and Characterization of Human GLP-1-Secreting L-cells in Primary Ileal Organoid Culture. Cell Rep 2020; 31:107833. [PMID: 32610134 PMCID: PMC7342002 DOI: 10.1016/j.celrep.2020.107833] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 05/10/2020] [Accepted: 06/08/2020] [Indexed: 12/12/2022] Open
Abstract
Glucagon-like peptide-1 (GLP-1) from intestinal L-cells stimulates insulin secretion and reduces appetite after food ingestion, and it is the basis for drugs against type-2 diabetes and obesity. Drugs targeting L- and other enteroendocrine cells are under development, with the aim to mimic endocrine effects of gastric bypass surgery, but they are difficult to develop without human L-cell models. Human ileal organoids, engineered by CRISPR-Cas9, express the fluorescent protein Venus in the proglucagon locus, enabling maintenance of live, identifiable human L-cells in culture. Fluorescence-activated cell sorting (FACS)-purified organoid-derived L-cells, analyzed by RNA sequencing (RNA-seq), express hormones, receptors, and ion channels, largely typical of their murine counterparts. L-cells are electrically active and exhibit membrane depolarization and calcium elevations in response to G-protein-coupled receptor ligands. Organoids secrete hormones in response to glucose and other stimuli. The ability to label and maintain human L-cells in organoid culture opens avenues to explore L-cell function and develop drugs targeting the human enteroendocrine system.
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Affiliation(s)
- Deborah A Goldspink
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Van B Lu
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Emily L Miedzybrodzka
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Christopher A Smith
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Rachel E Foreman
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Lawrence J Billing
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Richard G Kay
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Frank Reimann
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
| | - Fiona M Gribble
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
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12
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Abstract
In recent years, the importance of the gut microbiota in human health has been revealed and many publications have highlighted its role as a key component of human physiology. Owing to the use of modern sequencing approaches, the characterisation of the microbiome in healthy individuals and in disease has demonstrated a disturbance of the microbiota, or dysbiosis, associated with pathological conditions. The microbiota establishes a symbiotic crosstalk with their host: commensal microbes benefit from the nutrient-rich environment provided by the gut and the microbiota produces hundreds of proteins and metabolites that modulate key functions of the host, including nutrient processing, maintenance of energy homoeostasis and immune system development. Many bacteria-derived metabolites originate from dietary sources. Among them, an important role has been attributed to the metabolites derived from the bacterial fermentation of dietary fibres, namely SCFA linking host nutrition to intestinal homoeostasis maintenance. SCFA are important fuels for intestinal epithelial cells (IEC) and regulate IEC functions through different mechanisms to modulate their proliferation, differentiation as well as functions of subpopulations such as enteroendocrine cells, to impact gut motility and to strengthen the gut barrier functions as well as host metabolism. Recent findings show that SCFA, and in particular butyrate, also have important intestinal and immuno-modulatory functions. In this review, we discuss the mechanisms and the impact of SCFA on gut functions and host immunity and consequently on human health.
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13
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Cyranka M, Veprik A, McKay EJ, van Loon N, Thijsse A, Cotter L, Hare N, Saibudeen A, Lingam S, Pires E, Larraufie P, Reimann F, Gribble F, Stewart M, Bentley E, Lear P, McCullagh J, Cantley J, Cox RD, de Wet H. Abcc5 Knockout Mice Have Lower Fat Mass and Increased Levels of Circulating GLP-1. Obesity (Silver Spring) 2019; 27:1292-1304. [PMID: 31338999 PMCID: PMC6658130 DOI: 10.1002/oby.22521] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 04/09/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVE A previous genome-wide association study linked overexpression of an ATP-binding cassette transporter, ABCC5, in humans with a susceptibility to developing type 2 diabetes with age. Specifically, ABCC5 gene overexpression was shown to be strongly associated with increased visceral fat mass and reduced peripheral insulin sensitivity. Currently, the role of ABCC5 in diabetes and obesity is unknown. This study reports the metabolic phenotyping of a global Abcc5 knockout mouse. METHODS A global Abcc5-/- mouse was generated by CRISPR/Cas9. Fat mass was determined by weekly EchoMRI and fat pads were dissected and weighed at week 18. Glucose homeostasis was ascertained by an oral glucose tolerance test, intraperitoneal glucose tolerance test, and intraperitoneal insulin tolerance test. Energy expenditure and locomotor activity were measured using PhenoMaster cages. Glucagon-like peptide 1 (GLP-1) levels in plasma, primary gut cell cultures, and GLUTag cells were determined by enzyme-linked immunosorbent assay. RESULTS Abcc5-/- mice had decreased fat mass and increased plasma levels of GLP-1, and they were more insulin sensitive and more active. Recombinant overexpression of ABCC5 protein in GLUTag cells decreased GLP-1 release. CONCLUSIONS ABCC5 protein expression levels are inversely related to fat mass and appear to play a role in the regulation of GLP-1 secretion from enteroendocrine cells.
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Affiliation(s)
- Malgorzata Cyranka
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Anna Veprik
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Eleanor J. McKay
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Nienke van Loon
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Amber Thijsse
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Luke Cotter
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Nisha Hare
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Affan Saibudeen
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Swathi Lingam
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | | | - Pierre Larraufie
- Wellcome Trust‐MRC Institute of Metabolic ScienceAddenbrooke's HospitalCambridgeUK
| | - Frank Reimann
- Wellcome Trust‐MRC Institute of Metabolic ScienceAddenbrooke's HospitalCambridgeUK
| | - Fiona Gribble
- Wellcome Trust‐MRC Institute of Metabolic ScienceAddenbrooke's HospitalCambridgeUK
| | - Michelle Stewart
- MRC Harwell Institute, Genetics of Type 2 DiabetesMammalian Genetics Unit, Harwell CampusOxfordshireUK
| | - Elizabeth Bentley
- MRC Harwell Institute, Genetics of Type 2 DiabetesMammalian Genetics Unit, Harwell CampusOxfordshireUK
| | - Pamela Lear
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | | | - James Cantley
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Roger D. Cox
- MRC Harwell Institute, Genetics of Type 2 DiabetesMammalian Genetics Unit, Harwell CampusOxfordshireUK
| | - Heidi de Wet
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
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14
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Calcium Signaling Pathways: Key Pathways in the Regulation of Obesity. Int J Mol Sci 2019; 20:ijms20112768. [PMID: 31195699 PMCID: PMC6600289 DOI: 10.3390/ijms20112768] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 05/29/2019] [Accepted: 05/31/2019] [Indexed: 02/07/2023] Open
Abstract
Nowadays, high epidemic obesity-triggered hypertension and diabetes seriously damage social public health. There is now a general consensus that the body's fat content exceeding a certain threshold can lead to obesity. Calcium ion is one of the most abundant ions in the human body. A large number of studies have shown that calcium signaling could play a major role in increasing energy consumption by enhancing the metabolism and the differentiation of adipocytes and reducing food intake through regulating neuronal excitability, thereby effectively decreasing the occurrence of obesity. In this paper, we review multiple calcium signaling pathways, including the IP3 (inositol 1,4,5-trisphosphate)-Ca2+ (calcium ion) pathway, the p38-MAPK (mitogen-activated protein kinase) pathway, and the calmodulin binding pathway, which are involved in biological clock, intestinal microbial activity, and nerve excitability to regulate food intake, metabolism, and differentiation of adipocytes in mammals, resulting in the improvement of obesity.
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Dapper C, Schuster F, Stölting I, Vogt F, Castro e Souza LA, Alenina N, Bader M, Raasch W. The antiobese effect of AT1 receptor blockade is augmented in mice lacking Mas. Naunyn Schmiedebergs Arch Pharmacol 2019; 392:865-877. [DOI: 10.1007/s00210-019-01643-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/01/2019] [Indexed: 02/06/2023]
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16
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Adenosine triphosphate is co-secreted with glucagon-like peptide-1 to modulate intestinal enterocytes and afferent neurons. Nat Commun 2019; 10:1029. [PMID: 30833673 PMCID: PMC6399286 DOI: 10.1038/s41467-019-09045-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 02/01/2019] [Indexed: 02/02/2023] Open
Abstract
Enteroendocrine cells are specialised sensory cells located in the intestinal epithelium and generate signals in response to food ingestion. Whilst traditionally considered hormone-producing cells, there is evidence that they also initiate activity in the afferent vagus nerve and thereby signal directly to the brainstem. We investigate whether enteroendocrine L-cells, well known for their production of the incretin hormone glucagon-like peptide-1 (GLP-1), also release other neuro-transmitters/modulators. We demonstrate regulated ATP release by ATP measurements in cell supernatants and by using sniffer patches that generate electrical currents upon ATP exposure. Employing purinergic receptor antagonists, we demonstrate that evoked ATP release from L-cells triggers electrical responses in neighbouring enterocytes through P2Y2 and nodose ganglion neurones in co-cultures through P2X2/3-receptors. We conclude that L-cells co-secrete ATP together with GLP-1 and PYY, and that ATP acts as an additional signal triggering vagal activation and potentially synergising with the actions of locally elevated peptide hormone concentrations.
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Goldspink DA, Reimann F, Gribble FM. Models and Tools for Studying Enteroendocrine Cells. Endocrinology 2018; 159:3874-3884. [PMID: 30239642 PMCID: PMC6215081 DOI: 10.1210/en.2018-00672] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Accepted: 09/05/2018] [Indexed: 12/14/2022]
Abstract
Gut hormones produced by gastrointestinal enteroendocrine cells modulate key physiological processes including glucose homeostasis and food intake, making them potential therapeutic candidates to treat obesity and diabetes. Understanding the function of enteroendocrine cells and the molecular mechanisms driving hormone production is a key step toward mobilizing endogenous hormone reserves in the gut as a therapeutic strategy. In this review, we will discuss the variety of ex vivo and in vitro model systems driving this research and their contributions to our current understanding of nutrient-sensing mechanisms in enteroendocrine cells.
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Affiliation(s)
- Deborah A Goldspink
- Metabolic Research Laboratories, University of Cambridge, Cambridge, United Kingdom
| | - Frank Reimann
- Metabolic Research Laboratories, University of Cambridge, Cambridge, United Kingdom
| | - Fiona M Gribble
- Metabolic Research Laboratories, University of Cambridge, Cambridge, United Kingdom
- Correspondence: Fiona M. Gribble, DPhil, BM, BCh, Institute of Metabolic Science, University of Cambridge, Addenbrooke’s Hospital, Cambridge CB2 0QQ, United Kingdom. E-mail:
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18
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Ginés I, Gil-Cardoso K, Robles P, Arola L, Terra X, Blay M, Ardévol A, Pinent M. Novel ex Vivo Experimental Setup to Assay the Vectorial Transepithelial Enteroendocrine Secretions of Different Intestinal Segments. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:11622-11629. [PMID: 30148363 DOI: 10.1021/acs.jafc.8b03046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The enteroendocrine system coordinates gastrointestinal (GI) tract functionality and the whole organism. However, the scarcity of enteroendocrine cells and their scattered distribution make them difficult to study. Here, we glued segments of the GI wall of pigs to a silicon tube, keeping the apical and the basolateral sides separate. The fact that there was less than 1% of 70-kDa fluorescein isothiocyanate (FITC)-dextran on the basolateral side proved that the gluing was efficient. Since the lactate dehydrogenase leakage at basolateral side was lower than 0.1% (1.40 ± 0.17 nKatals) it proved that the tissue was viable. The intestinal barrier function was maintained as it is in segments mounted in Ussing chambers (the amount of Lucifer Yellow crossing it, was similar between them; respectively, % LY, 0.48 ± 0.13; 0.52 ± 0.09; p > 0.05). Finally, apical treatments with two different extract produced differential basolateral enterohormone secretions (basolateral PYY secretion vs control; animal extract, 0.35 ± 0.16; plant extract, 2.5 ± 0.74; p < 0.05). In conclusion, we report an ex vivo system called "Ap-to-Bas" for assaying vectorial transepithelial processes that makes it possible to work with several samples at the same time. It is an optimal device for enterohormone studies in the intestine.
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19
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Adriaenssens AE, Reimann F, Gribble FM. Distribution and Stimulus Secretion Coupling of Enteroendocrine Cells along the Intestinal Tract. Compr Physiol 2018; 8:1603-1638. [DOI: 10.1002/cphy.c170047] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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20
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Billing LJ, Smith CA, Larraufie P, Goldspink DA, Galvin S, Kay RG, Howe JD, Walker R, Pruna M, Glass L, Pais R, Gribble FM, Reimann F. Co-storage and release of insulin-like peptide-5, glucagon-like peptide-1 and peptideYY from murine and human colonic enteroendocrine cells. Mol Metab 2018; 16:65-75. [PMID: 30104166 PMCID: PMC6158034 DOI: 10.1016/j.molmet.2018.07.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 07/20/2018] [Accepted: 07/24/2018] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE Insulin-like peptide-5 (INSL5) is an orexigenic gut hormone found in a subset of colonic and rectal enteroendocrine L-cells together with the anorexigenic hormones glucagon-like peptide-1 (GLP-1) and peptideYY (PYY). Unlike GLP-1 and PYY, INSL5 levels are elevated by calorie restriction, raising questions about how these hormones respond to different stimuli when they arise from the same cell type. The aim of the current study was to identify whether and how INSL5, GLP-1 and PYY are co-secreted or differentially secreted from colonic L-cells. METHODS An inducible reporter mouse (Insl5-rtTA) was created to enable selective characterisation of Insl5-expressing cells. Expression profiling and Ca2+-dynamics were assessed using TET-reporter mice. Secretion of INSL5, PYY, and GLP-1 from murine and human colonic crypt cultures was quantified by tandem mass spectrometry. Vesicular co-localisation of the three hormones was analysed in 3D-SIM images of immunofluorescently-labelled murine colonic primary cultures and tissue sections. RESULTS INSL5-producing cells expressed a range of G-protein coupled receptors previously identified in GLP-1 expressing L-cells, including Ffar1, Gpbar1, and Agtr1a. Pharmacological or physiological agonists for these receptors triggered Ca2+ transients in INSL5-producing cells and stimulated INSL5 secretion. INSL5 secretory responses strongly correlated with those of PYY and GLP-1 across a range of stimuli. The majority (>80%) of secretory vesicles co-labelled for INSL5, PYY and GLP-1. CONCLUSIONS INSL5 is largely co-stored with PYY and GLP-1 and all three hormones are co-secreted when INSL5-positive cells are stimulated. Opposing hormonal profiles observed in vivo likely reflect differential stimulation of L-cells in the proximal and distal gut.
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Affiliation(s)
- Lawrence J Billing
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Christopher A Smith
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Pierre Larraufie
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Deborah A Goldspink
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Sam Galvin
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Richard G Kay
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | | | - Ryan Walker
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Mihai Pruna
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Leslie Glass
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Ramona Pais
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Fiona M Gribble
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK.
| | - Frank Reimann
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK.
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Psichas A, Larraufie PF, Goldspink DA, Gribble FM, Reimann F. Chylomicrons stimulate incretin secretion in mouse and human cells. Diabetologia 2017; 60:2475-2485. [PMID: 28866808 PMCID: PMC5850988 DOI: 10.1007/s00125-017-4420-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 07/07/2017] [Indexed: 01/05/2023]
Abstract
AIMS/HYPOTHESIS Lipids are a potent stimulus for the secretion of glucagon-like peptide (GLP)-1 and glucose-dependent insulinotropic peptide (GIP). Traditionally, this effect was thought to involve the sensing of lipid digestion products by free fatty acid receptor 1 (FFA1) and G-protein coupled receptor 119 (GPR119) on the apical surface of enteroendocrine cells. However, recent evidence suggests that lipids may in fact be sensed basolaterally, and that fatty acid absorption and chylomicron synthesis may be a prerequisite for their stimulatory effect on gut peptide release. Therefore, we investigated the effect of chylomicrons on GLP-1 and GIP secretion in vitro. METHODS The effect of chylomicrons on incretin secretion was investigated using GLUTag cells and duodenal cultures of both murine and human origin. The role of lipoprotein lipase (LPL) and FFA1 in GLUTag cells was assessed by pharmacological inhibition and small (short) interfering RNA (siRNA)-mediated knockdown. The effect of chylomicrons on intracellular calcium concentration ([Ca2+]i) was determined by imaging GLUTag cells loaded with Fura-2. In the primary setting, the contributions of FFA1 and GPR119 were investigated using L cell-specific Gpr119 knockout cultures treated with the FFA1 antagonist GW1100. RESULTS Chylomicrons stimulated GLP-1 release from GLUTag cells, and both GLP-1 and GIP secretion from human and murine duodenal cultures. Chylomicron-triggered GLP-1 secretion from GLUTag cells was largely abolished following lipase inhibition with orlistat or siRNA-mediated knockdown of Lpl. In GLUTag cells, both GW1100 and siRNA-mediated Ffar1 knockdown reduced GLP-1 secretion in response to chylomicrons, and, consistent with FFA1 Gq-coupling, chylomicrons triggered an increase in [Ca2+]i. However, LPL and FFA1 inhibition had no significant effect on chylomicron-mediated incretin secretion in murine cultures. Furthermore, the loss of GPR119 had no impact on GLP-1 secretion in response to chylomicrons, even in the presence of GW1100. CONCLUSIONS/INTERPRETATION Chylomicrons stimulate incretin hormone secretion from GLUTag cells as well as from human and murine duodenal cultures. In GLUTag cells, the molecular pathway was found to involve LPL-mediated lipolysis, leading to the release of lipid species that activated FFA1 and elevated intracellular calcium.
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Affiliation(s)
- Arianna Psichas
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, WT-MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Pierre F Larraufie
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, WT-MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Deborah A Goldspink
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, WT-MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Fiona M Gribble
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, WT-MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK.
| | - Frank Reimann
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, WT-MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK.
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22
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Goldspink DA, Lu VB, Billing LJ, Larraufie P, Tolhurst G, Gribble FM, Reimann F. Mechanistic insights into the detection of free fatty and bile acids by ileal glucagon-like peptide-1 secreting cells. Mol Metab 2017; 7:90-101. [PMID: 29167062 PMCID: PMC5784317 DOI: 10.1016/j.molmet.2017.11.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 11/04/2017] [Accepted: 11/06/2017] [Indexed: 02/07/2023] Open
Abstract
Objectives The aim of this study was to investigate the electrical properties of ileal Glucagon-like peptide 1 (GLP-1) secreting L-cells using murine organoid cultures and the electrophysiological and intracellular signaling pathways recruited following activation of the Gαq-coupled free fatty acid receptors FFA1 and Gαs-coupled bile acid receptors GPBAR1. Methods Experiments were performed using ileal organoids generated from mice transgenically expressing fluorescent reporters (Epac2-camps and GCaMP3) under control of the proglucagon promoter. Electrophysiology and single cell imaging were performed on identified L-cells in organoids, and GLP-1 secretion from cultured organoids was measured by immunoassay. Results The FFA1 ligand TAK-875 triggered L-cell electrical activity, increased intracellular calcium, and activated a depolarizing current that was blocked by the TRPC3 inhibitor Pyr3. TAK-875 triggered GLP-1 secretion was Pyr3 sensitive, suggesting that the TRPC3 channel links FFA1 activation to calcium elevation and GLP-1 release in L-cells. GPBAR1 agonist triggered PKA-dependent L-type Ca2+ current activation and action potential firing in L-cells. The combination of TAK-875 and a GPBAR1 agonist triggered synergistic calcium elevation and GLP-1 secretory responses. Conclusions FFA1 and GPBAR1 activation individually increased electrical activity in L-cells by recruiting pathways that include activation of TRPC3 and L-type voltage-gated Ca2+ channels. Synergy between the pathways activated downstream of these receptors was observed both at the level of Ca2+ elevation and GLP-1 secretion. Organoid-derived ileal L-cells recapitulate the properties of primary ileal L-cells. GPBAR1 agonism stimulates L-type Ca2+ current-dependent action potentials in L-cells. FFA1 agonists depolarize L-cells via TRPC3 activation. Synergy between GPBAR1/FFA1 occurs at the levels of Ca2+ responses and secretion.
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Affiliation(s)
- Deborah A Goldspink
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Van B Lu
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Lawrence J Billing
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Pierre Larraufie
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Gwen Tolhurst
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Fiona M Gribble
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
| | - Frank Reimann
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
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Psichas A, Tolhurst G, Brighton CA, Gribble FM, Reimann F. Mixed Primary Cultures of Murine Small Intestine Intended for the Study of Gut Hormone Secretion and Live Cell Imaging of Enteroendocrine Cells. J Vis Exp 2017. [PMID: 28448057 PMCID: PMC5409300 DOI: 10.3791/55687] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The gut is the largest endocrine organ of the body, with hormone-secreting enteroendocrine cells located along the length of the gastrointestinal epithelium. Despite their physiological importance, enteroendocrine cells represent only a small fraction of the epithelial cell population and in the past, their characterization has presented a considerable challenge resulting in a reliance on cell line models. Here, we provide a detailed protocol for the isolation and culture of mixed murine small intestinal cells. These primary cultures have been used to identify the signaling pathways underlying the stimulation and inhibition of gut peptide secretion in response to a number of nutrients and neuropeptides as well as pharmacological agents. Furthermore, in combination with the use of transgenic fluorescent reporter mice, we have demonstrated that these primary cultures become a powerful tool for the examination of fluorescently-tagged enteroendocrine cells at the intracellular level, using methods such as patch clamping and single-cell calcium and cAMP-FRET imaging.
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Affiliation(s)
- Arianna Psichas
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge
| | - Gwen Tolhurst
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge
| | - Cheryl A Brighton
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge
| | - Fiona M Gribble
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge;
| | - Frank Reimann
- Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge;
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24
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Abstract
PURPOSE OF THE REVIEW Evidence is rapidly accumulating implicating gut dysbiosis in hypertension (HTN). However, we are far from understanding whether this is a cause or consequence of HTN, and how to best translate this fundamental knowledge to advance the management of HTN. This review aims to summarize recent advances in the field, illustrate the connections between the gut and hypertension, and establish that the gut microbiota (GM)-gut interaction is centrally positioned for consideration as an innovative approach for HTN therapeutics. RECENT FINDINGS Animal models of HTN have shown that gut pathology occurs in HTN, and provides some clues to mechanisms linking the dysbiosis, gut pathology, and HTN. Circumstantial evidence links gut dysbiosis and HTN. Gut pathology, apparent in animal HTN models, has not been fully investigated in hypertensive patients. Objective evidence and an understanding of mechanisms could have a major impact for new antihypertensive therapies and/or improved applications of current ones.
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Affiliation(s)
- Elaine M Richards
- Departments of Physiology and Functional Genomics, University of Florida, PO Box 100274, Gainesville, FL, 32610-0274, USA
| | - Carl J Pepine
- Department of Medicine, Division of Cardiovascular Medicine, University of Florida, Gainesville, Florida, USA
| | - Mohan K Raizada
- Departments of Physiology and Functional Genomics, University of Florida, PO Box 100274, Gainesville, FL, 32610-0274, USA.
| | - Seungbum Kim
- Departments of Physiology and Functional Genomics, University of Florida, PO Box 100274, Gainesville, FL, 32610-0274, USA
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