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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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Yadav D, Wairagu PM, Kwak M, Jin JO, Jin JO. Nanoparticle-Based Inhalation Therapy for Pulmonary Diseases. Curr Drug Metab 2022; 23:882-896. [PMID: 35927812 DOI: 10.2174/1389200223666220803103039] [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: 02/01/2022] [Revised: 04/04/2022] [Accepted: 04/29/2022] [Indexed: 01/05/2023]
Abstract
The lung is exposed to various pollutants and is the primary site for the onset of various diseases, including infections, allergies, and cancers. One possible treatment approach for such pulmonary diseases involves direct administration of therapeutics to the lung so as to maintain the topical concentration of the drug. Particles with nanoscale diameters tend to reach the pulmonary region. Nanoparticles (NPs) have garnered significant interest for applications in biomedical and pharmaceutical industries because of their unique physicochemical properties and biological activities. In this article, we describe the biological and pharmacological activities of NPs as well as summarize their potential in the formulation of drugs employed to treat pulmonary diseases. Recent advances in the use of NPs in inhalation chemotherapy for the treatment of lung diseases have also been highlighted.
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Affiliation(s)
- Dhananjay Yadav
- Department of Life Science, Yeungnam University, Gyeongsan 38541, South Korea
| | - Peninah M Wairagu
- Department of Biochemistry and Biotechnology, The Technical University of Kenya, Nairobi, Kenya
| | - Minseok Kwak
- Department of Chemistry, Pukyong National University, Busan 48513, Korea
| | - Jun-O Jin
- Department of Microbiology, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Jun-O Jin
- Department of Biotechnology, ITM University, Gwalior, Madhya Pradesh, 474011, India.,Research Institute of Cell Culture, Yeungnam University, Gyeongsan 38541, Korea
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Holzer P, Holzer-Petsche U. Constipation Caused by Anti-calcitonin Gene-Related Peptide Migraine Therapeutics Explained by Antagonism of Calcitonin Gene-Related Peptide's Motor-Stimulating and Prosecretory Function in the Intestine. Front Physiol 2022; 12:820006. [PMID: 35087426 PMCID: PMC8787053 DOI: 10.3389/fphys.2021.820006] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/17/2021] [Indexed: 12/12/2022] Open
Abstract
The development of small-molecule calcitonin gene-related peptide (CGRP) receptor antagonists (gepants) and of monoclonal antibodies targeting the CGRP system has been a major advance in the management of migraine. In the randomized controlled trials before regulatory approval, the safety of these anti-CGRP migraine therapeutics was considered favorable and to stay within the expected profile. Post-approval real-world surveys reveal, however, constipation to be a major adverse event which may affect more than 50% of patients treated with erenumab (an antibody targeting the CGRP receptor), fremanezumab or galcanezumab (antibodies targeting CGRP). In this review article we address the question whether constipation caused by inhibition of CGRP signaling can be mechanistically deduced from the known pharmacological actions and pathophysiological implications of CGRP in the digestive tract. CGRP in the gut is expressed by two distinct neuronal populations: extrinsic primary afferent nerve fibers and distinct neurons of the intrinsic enteric nervous system. In particular, CGRP is a major messenger of enteric sensory neurons which in response to mucosal stimulation activate both ascending excitatory and descending inhibitory neuronal pathways that enable propulsive (peristaltic) motor activity to take place. In addition, CGRP is able to stimulate ion and water secretion into the intestinal lumen. The motor-stimulating and prosecretory actions of CGRP combine in accelerating intestinal transit, an activity profile that has been confirmed by the ability of CGRP to induce diarrhea in mice, dogs and humans. We therefore conclude that the constipation elicited by antibodies targeting CGRP or its receptor results from interference with the physiological function of CGRP in the small and large intestine in which it contributes to the maintenance of peristaltic motor activity, ion and water secretion and intestinal transit.
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Affiliation(s)
- Peter Holzer
- Division of Pharmacology, Otto Loewi Research Centre, Medical University of Graz, Graz, Austria
| | - Ulrike Holzer-Petsche
- Division of Pharmacology, Otto Loewi Research Centre, Medical University of Graz, Graz, Austria
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Nakamori H, Iida K, Hashitani H. Mechanisms underlying the prokinetic effects of endogenous glucagon-like peptide-1 in the rat proximal colon. Am J Physiol Gastrointest Liver Physiol 2021; 321:G617-G627. [PMID: 34643099 DOI: 10.1152/ajpgi.00175.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 09/24/2021] [Accepted: 10/06/2021] [Indexed: 01/31/2023]
Abstract
Glucagon-like peptide-1 (GLP-1), a well-known insulin secretagogue, is released from enteroendocrine L cells both luminally and basolaterally to exert different effects. Basolaterally released GLP-1 increases epithelial ion transport by activating CGRP-containing enteric afferent neurons. Although bath-applied GLP-1 reduced the contractility of colonic segments, GLP-1-induced stimulation of afferent neurons could also accelerate peristaltic contractions. Here, the roles of endogenous GLP-1 in regulating colonic peristalsis were investigated using isolated colonic segments. Isolated segments of rat proximal colon were placed in an organ bath, serosally perfused with oxygenated physiological salt solution, and luminally perfused with degassed 0.9% saline. Colonic wall motion was recorded using a video camera and converted into spatiotemporal maps. Intraluminal administration of GLP-1 (100 nM) stimulating the secretion of GLP-1 from L cells increased the frequency of oro-aboral propagating peristaltic contractions. The acceleratory effect of GLP-1 was blocked by luminally applied exendin-3 (9-39) (100 nM), a GLP-1 receptor antagonist. GLP-1-induced acceleration of peristaltic contractions was also prevented by bath-applied BIBN4069 (1 μM), a CGRP receptor antagonist. In colonic segments that had been exposed to bath-applied capsaicin (100 nM) that desensitizes extrinsic afferents, GLP-1 was still capable of exerting its prokinetic effect. Stimulation of endogenous GLP-1 secretion with a luminally applied cocktail of short-chain fatty acids (1 mM) increased the frequency of peristaltic waves in an exendin-3 (9-39)-sensitive manner. Thus, GLP-1 activates CGRP-expressing intrinsic afferents to accelerate peristalsis in the proximal colon. Short-chain fatty acids appear to stimulate endogenous GLP-1 secretion from L cells resulting in the acceleration of colonic peristalsis.NEW & NOTEWORTHY Glucagon-like peptide-1 (GLP-1) activates CGRP-containing intrinsic afferent neurons resulting in the acceleration of colonic peristalsis. Short-chain fatty acids stimulate the secretion of endogenous GLP-1 from L cells that accelerates colonic peristalsis. Thus, besides the well-known humoral insulinotropic action, GLP-1 exerts a local action via the activation of the enteric nervous system to accelerate colonic motility. Such a prokinetic action of GLP-1 could underlie the mechanisms causing diarrhea in patients with type-2 diabetes treated with GLP-1 analogs.
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Affiliation(s)
- Hiroyuki Nakamori
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Koji Iida
- 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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Tough IR, Schwartz TW, Cox HM. Synthetic G protein-coupled bile acid receptor agonists and bile acids act via basolateral receptors in ileal and colonic mucosa. Neurogastroenterol Motil 2020; 32:e13943. [PMID: 32656959 DOI: 10.1111/nmo.13943] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/29/2020] [Accepted: 06/22/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND The G protein-coupled bile acid (BA) receptor, GPBA (previously named TGR5), mediates BA gastrointestinal (GI) activities. Our aim was to elucidate the mucosal and motility responses to selective GPBA agonists compared with conjugated BA (eg, taurodeoxycholate, TDCA) in mouse and human colon. METHODS Ion transport responses to GPBA agonists or BAs were measured in mucosal preparations with intact submucous innervation, from C57Bl/6, PYY-/-, or GPBA-/- mice and compared with GPBA signaling in human colon. We also investigated the mechanisms underlying GPBA agonism in mucosae and on natural fecal pellet propulsion. KEY RESULTS GPBA agonist Merck V stimulated basolateral responses involving peptide YY (PYY), cholinergic, and 5-HT mechanisms in colonic mucosa. The PYY-mediated GPBA signal was glucose-sensitive. Luminal TDCA crossed the epithelial lining via the apical sodium-dependent BA transporter (ASBT) and its inhibitor, GSK2330672 significantly reduced luminal, but not basolateral TDCA activity. Merck V also slowed natural fecal pellet progression in wild-type and PYY-/- colons but not in GPBA-/- colon, while TDCA increased motility in wild-type colon. The antimotile GPBA effect was reversed by blockade of glucagon-like peptide 1 (GLP-1) receptors or nitric oxide synthase, indicating involvement of GLP-1 and nitric oxide. CONCLUSIONS & INFERENCES We conclude that several different targets within the lamina propria express GPBA, including L cells (that release PYY and GLP-1), enterochromaffin cells and neurons (that release 5-HT), and other enteric neurons. Furthermore, luminal-conjugated BAs require transport across the epithelium via ASBT in order to activate basolateral GPBA.
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Affiliation(s)
- Iain R Tough
- King's College London, Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Thue W Schwartz
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Section for Metabolic Receptology and Enteroendocrinology, University of Copenhagen, Copenhagen, Denmark
| | - Helen M Cox
- King's College London, Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, London, UK
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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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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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Tough IR, Forbes S, Herzog H, Jones RM, Schwartz TW, Cox HM. Bidirectional GPR119 Agonism Requires Peptide YY and Glucose for Activity in Mouse and Human Colon Mucosa. Endocrinology 2018; 159:1704-1717. [PMID: 29471473 PMCID: PMC5972582 DOI: 10.1210/en.2017-03172] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 02/05/2018] [Indexed: 12/22/2022]
Abstract
The lipid sensor G protein-coupled receptor 119 (GPR119) is highly expressed by enteroendocrine L-cells and pancreatic β-cells that release the hormones, peptide YY (PYY) and glucagonlike peptide 1, and insulin, respectively. Endogenous oleoylethanolamide (OEA) and the dietary metabolite, 2-monoacylglycerol (2-OG), can each activate GPR119. Here, we compared mucosal responses with selective, synthetic GPR119 agonists (AR440006 and AR231453) and the lipids, OEA, 2-OG, and N-oleoyldopamine (OLDA), monitoring epithelial ion transport as a readout for L-cell activity in native mouse and human gastrointestinal (GI) mucosae. We also assessed GPR119 modulation of colonic motility in wild-type (WT), GPR119-deficient (GPR119-/-), and PYY-deficient (PYY-/-) mice. The water-soluble GPR119 agonist, AR440006 (that cannot traverse epithelial tight junctions), elicited responses, when added apically or basolaterally in mouse and human colonic mucosae. In both species, GPR119 responses were PYY, Y1 receptor mediated, and glucose dependent. AR440006 efficacy matched the GI distribution of L-cells in WT tissues but was absent from GPR119-/- tissue. OEA and 2-OG responses were significantly reduced in the GPR119-/- colon, but OLDA responses were unchanged. Alternative L-cell activation via free fatty acid receptors 1, 3, and 4 and the G protein-coupled bile acid receptor TGR5 or by the melanocortin 4 receptor, was unchanged in GPR119-/- tissues. The GPR119 agonist slowed transit in WT but not the PYY-/- colon in vitro. AR440006 (intraperitoneally) slowed WT colonic and upper-GI transit significantly in vivo. These data indicate that luminal or blood-borne GPR119 agonism can stimulate L-cell PYY release with paracrine consequences and slower motility. We suggest that this glucose-dependent L-cell response to a gut-restricted GPR119 stimulus has potential therapeutic advantage in modulating insulinotropic signaling with reduced risk of hypoglycemia.
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Affiliation(s)
- Iain R Tough
- King’s College London, Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, London, United Kingdom
| | - Sarah Forbes
- King’s College London, Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, London, United Kingdom
| | - Herbert Herzog
- Garvan Institute of Medical Research, Darlinghurst New South Wales, Sydney, Australia
| | - Robert M Jones
- Department of Medicinal Chemistry, Arena Pharmaceuticals, San Diego, California
| | - Thue W Schwartz
- Section for Metabolic Receptology and Enteroendocrinology, Novo Nordisk Foundation Centre for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Helen M Cox
- King’s College London, Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, London, United Kingdom
- Correspondence: Helen M. Cox, PhD, Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London SE1 1UL, United Kingdom. E-mail:
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Moodaley R, Smith DM, Tough IR, Schindler M, Cox HM. Agonism of free fatty acid receptors 1 and 4 generates peptide YY-mediated inhibitory responses in mouse colon. Br J Pharmacol 2017; 174:4508-4522. [PMID: 28971469 DOI: 10.1111/bph.14054] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 09/16/2017] [Accepted: 09/20/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND AND PURPOSE Free fatty acid receptors FFA1 and FFA4 are located on enteroendocrine L cells with the highest gastrointestinal (GI) expression in descending colon. Their activation causes the release of glucagon-like peptide 1 and peptide YY (PYY) from L cells. Additionally, FFA1 agonism releases insulin from pancreatic β cells. As these receptors are modulators of nutrient-stimulated glucose regulation, the aim of this study was to compare the pharmacology of commercially available agonists (TUG424, TUG891, GW9508) with proven selective agonists (JTT, TAK-875, AZ423, Metabolex-36) in mice. EXPERIMENTAL APPROACH Mouse mucosa was mounted in Ussing chambers, voltage-clamped and the resultant short-circuit current (Isc ) was recorded continuously. Pretreatments included antagonists of FFA1, Y1 or Y2 receptors. Glucose sensitivity was investigated by mannitol replacement apically, and colonic and upper GI transit was assessed in vitro and in vivo. KEY RESULTS FFA1 and FFA4 agonism required glucose and reduced Isc in a PYY-Y1 receptor-dependent manner. The novel compounds were more potent than GW9508. The FFA1 antagonists (GW1100 and ANT825) blocked FFA1 activity only and revealed FFA1 tonic activity. The FFA4 agonist, Metabolex-36, slowed colonic transit in vitro but increased small intestinal transit in vivo. CONCLUSIONS AND IMPLICATIONS The selective FFA1 and FFA4 agonists were more potent at reducing Isc than GW9508, a dual FFA1 and FFA4 agonist. A paracrine epithelial mechanism involving PYY-stimulated Y1 receptors mediated their responses, which were glucose sensitive, potentially limiting hypoglycaemia. ANT825 revealed tonic activity and the possibility of endogenous FFA1 ligands causing PYY release. Finally, FFA4 agonism induced regional differences in transit.
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Affiliation(s)
- Runisha Moodaley
- Wolfson Centre for Age-Related Diseases, King's College London, London, UK
| | - David M Smith
- Discovery Sciences, Innovative Medicines & Early Development Biotech Unit, AstraZeneca, Cambridge, UK
| | - Iain R Tough
- Wolfson Centre for Age-Related Diseases, King's College London, London, UK
| | - Marcus Schindler
- AstraZeneca Mölndal, Innovative Medicines & Early Development, Cardiovascular & Metabolic Diseases iMed, Mölndal, Sweden
| | - Helen M Cox
- Wolfson Centre for Age-Related Diseases, King's College London, London, UK
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