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Modvig IM, Smits MM, Galsgaard KD, Hjørne AP, Drzazga AK, Rosenkilde MM, Holst JJ. L-valine is a powerful stimulator of GLP-1 secretion in rodents and stimulates secretion through ATP-sensitive potassium channels and voltage-gated calcium channels. Nutr Diabetes 2024; 14:43. [PMID: 38862477 PMCID: PMC11166632 DOI: 10.1038/s41387-024-00303-4] [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: 01/23/2024] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/13/2024] Open
Abstract
BACKGROUND We previously reported that, among all the naturally occurring amino acids, L-valine is the most powerful luminal stimulator of glucagon-like peptide 1 (GLP-1) release from the upper part of the rat small intestine. This makes L-valine an interesting target for nutritional-based modulation of GLP-1 secretion. However, the molecular mechanism of L-valine-induced secretion remains unknown. METHODS We aimed to investigate the effect of orally given L-valine in mice and to identify the molecular details of L-valine stimulated GLP-1 release using the isolated perfused rat small intestine and GLUTag cells. In addition, the effect of L-valine on hormone secretion from the distal intestine was investigated using a perfused rat colon. RESULTS Orally given L-valine (1 g/kg) increased plasma levels of active GLP-1 comparably to orally given glucose (2 g/kg) in male mice, supporting that L-valine is a powerful stimulator of GLP-1 release in vivo (P > 0.05). Luminal L-valine (50 mM) strongly stimulated GLP-1 release from the perfused rat small intestine (P < 0.0001), and inhibition of voltage-gated Ca2+-channels with nifedipine (10 μM) inhibited the GLP-1 response (P < 0.01). Depletion of luminal Na+ did not affect L-valine-induced GLP-1 secretion (P > 0.05), suggesting that co-transport of L-valine and Na+ is not important for the depolarization necessary to activate the voltage-gated Ca2+-channels. Administration of the KATP-channel opener diazoxide (250 μM) completely blocked the L-valine induced GLP-1 response (P < 0.05), suggesting that L-valine induced depolarization arises from metabolism and opening of KATP-channels. Similar to the perfused rat small intestine, L-valine tended to stimulate peptide tyrosine-tyrosine (PYY) and GLP-1 release from the perfused rat colon. CONCLUSIONS L-valine is a powerful stimulator of GLP-1 release in rodents. We propose that intracellular metabolism of L-valine leading to closure of KATP-channels and opening of voltage-gated Ca2+-channels are involved in L-valine induced GLP-1 secretion.
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Affiliation(s)
- Ida Marie Modvig
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mark M Smits
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Katrine Douglas Galsgaard
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anna Pii Hjørne
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anna Katarzyna Drzazga
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Institute of Molecular and Industrial Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Łódź, Poland
| | - Mette Marie Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Juul Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.
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Zou J, Gao J, Sun L, Liu Y, Ma C, Chen S, Zheng Y, Wu S, Gao X. Perceived Taste and Olfactory Dysfunctions and Subsequent Stroke Risk. JACC. ASIA 2024; 4:483-492. [PMID: 39100703 PMCID: PMC11291397 DOI: 10.1016/j.jacasi.2024.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 02/02/2024] [Accepted: 02/03/2024] [Indexed: 08/06/2024]
Abstract
Background Taste and olfactory dysfunction are commonly associated with neurodegenerative diseases and cardiovascular risk factors, but their specific associations with stroke risk remain uncertain. Objectives The purpose of this paper was to explore whether perceived taste and olfactory dysfunctions were associated with stroke risk. Methods Included were 85,656 participants (mean age 51.0 ± 15.3 years) of the Kailuan study. Perceived olfactory and taste dysfunctions were assessed via a questionnaire at baseline (in 2014-2016). Incident stroke cases were confirmed by review of medical records. Cox proportional hazards models were used to investigate associations of perceived olfactory and taste dysfunctions with stroke risk, and mediation analysis was used to estimate the mediating effect of chronic disease statuses. Results We documented 2,198 incident stroke cases during a mean of 5.6 years of follow-up. Perceived taste dysfunction was associated with a doubled risk of developing total stroke (adjusted HR: 2.03; 95% CI: 1.36-3.04; P < 0.001) even with adjustment of lifestyle factors, biomarkers (ie, blood lipids, blood glucose, blood pressure, and uric acid), and other potential confounders. However, perceived olfactory dysfunction (adjusted HR: 1.22; 95% CI: 0.79-1.90; P = 0.34) was not significantly associated with a high risk of total stroke. Similar results of both perceived taste and olfactory dysfunctions were observed for ischemic stroke. Presence of chronic diseases, including hypertension, diabetes, chronic kidney disease, and overweight/obesity, mediated 4% to 5% of the association of perceived taste dysfunction with both total stroke and ischemic stroke. Conclusions In this large cohort study, perceived taste dysfunction was associated with a high risk of developing stroke.
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Affiliation(s)
- Jiaojiao Zou
- Department of Nutrition and Food Hygiene, School of Public Health, Institute of Nutrition, Fudan University, Shanghai, China
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
| | - Jingli Gao
- Department of Intensive Care Unit, Kailuan General Hospital, Tangshan, China
| | - Liang Sun
- Department of Nutrition and Food Hygiene, School of Public Health, Institute of Nutrition, Fudan University, Shanghai, China
| | - Yesong Liu
- Department of Neurology, Kailuan General Hospital, Tangshan, China
| | - Chaoran Ma
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Shuohua Chen
- Department of Cardiology, Kailuan General Hospital, Tangshan, China
| | - Yan Zheng
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
| | - Shouling Wu
- Department of Cardiology, Kailuan General Hospital, Tangshan, China
| | - Xiang Gao
- Department of Nutrition and Food Hygiene, School of Public Health, Institute of Nutrition, Fudan University, Shanghai, China
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Rezaie P, Bitarafan V, Rose BD, Lange K, Mohammadpour Z, Rehfeld JF, Horowitz M, Feinle-Bisset C. Effects of Quinine on the Glycaemic Response to, and Gastric Emptying of, a Mixed-Nutrient Drink in Females and Males. Nutrients 2023; 15:3584. [PMID: 37630774 PMCID: PMC10459881 DOI: 10.3390/nu15163584] [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: 06/27/2023] [Revised: 08/09/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Intraduodenal quinine, in the dose of 600 mg, stimulates glucagon-like peptide-1 (GLP-1), cholecystokinin and insulin; slows gastric emptying (GE); and lowers post-meal glucose in men. Oral sensitivity to bitter substances may be greater in women than men. We, accordingly, evaluated the dose-related effects of quinine on GE, and the glycaemic responses to, a mixed-nutrient drink in females, and compared the effects of the higher dose with those in males. A total of 13 female and 13 male healthy volunteers received quinine-hydrochloride (600 mg ('QHCl-600') or 300 mg ('QHCl-300', females only) or control ('C'), intraduodenally (10 mL bolus) 30 min before a drink (500 kcal, 74 g carbohydrates). Plasma glucose, insulin, C-peptide, GLP-1, glucose-dependent insulinotropic polypeptide (GIP) and cholecystokinin were measured at baseline, for 30 min after quinine alone, and then for 2 h post-drink. GE was measured by 13C-acetate breath-test. QHCl-600 alone stimulated insulin, C-peptide and GLP-1 secretion compared to C. Post-drink, QHCl-600 reduced plasma glucose, stimulated C-peptide and GLP-1, and increased the C-peptide/glucose ratio and oral disposition index, while cholecystokinin and GIP were less, in females and males. QHCl-600 also slowed GE compared to C in males and compared to QHCl-300 in females (p < 0.05). QHCl-300 reduced post-meal glucose concentrations and increased the C-peptide/glucose ratio, compared to C (p < 0.05). Magnitudes of glucose lowering and increase in C-peptide/glucose ratio by QHCl-600 were greater in females than males (p < 0.05). We conclude that quinine modulates glucoregulatory functions, associated with glucose lowering in healthy males and females. However, glucose lowering appears to be greater in females than males, without apparent differential effects on GI functions.
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Affiliation(s)
- Peyman Rezaie
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, SA 5005, Australia
| | - Vida Bitarafan
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, SA 5005, Australia
| | - Braden David Rose
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, SA 5005, Australia
- Nutrition, Diabetes and Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute, Adelaide, SA 5001, Australia
| | - Kylie Lange
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, SA 5005, Australia
| | - Zinat Mohammadpour
- Nutrition, Diabetes and Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute, Adelaide, SA 5001, Australia
- School of Biomedicine, University of Adelaide, Adelaide, SA 5005, Australia
| | - Jens Frederik Rehfeld
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Michael Horowitz
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, SA 5005, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, SA 5005, Australia
| | - Christine Feinle-Bisset
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, SA 5005, Australia
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Paulussen F, Kulkarni CP, Stolz F, Lescrinier E, De Graeve S, Lambin S, Marchand A, Chaltin P, In't Veld P, Mebis J, Tavernier J, Van Dijck P, Luyten W, Thevelein JM. The β2-adrenergic receptor in the apical membrane of intestinal enterocytes senses sugars to stimulate glucose uptake from the gut. Front Cell Dev Biol 2023; 10:1041930. [PMID: 36699012 PMCID: PMC9869975 DOI: 10.3389/fcell.2022.1041930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 12/14/2022] [Indexed: 01/12/2023] Open
Abstract
The presence of sugar in the gut causes induction of SGLT1, the sodium/glucose cotransporter in intestinal epithelial cells (enterocytes), and this is accompanied by stimulation of sugar absorption. Sugar sensing was suggested to involve a G-protein coupled receptor and cAMP - protein kinase A signalling, but the sugar receptor has remained unknown. We show strong expression and co-localization with SGLT1 of the β2-adrenergic receptor (β 2-AR) at the enterocyte apical membrane and reveal its role in stimulating glucose uptake from the gut by the sodium/glucose-linked transporter, SGLT1. Upon heterologous expression in different reporter systems, the β 2-AR responds to multiple sugars in the mM range, consistent with estimated gut sugar levels after a meal. Most adrenergic receptor antagonists inhibit sugar signaling, while some differentially inhibit epinephrine and sugar responses. However, sugars did not inhibit binding of I125-cyanopindolol, a β 2-AR antagonist, to the ligand-binding site in cell-free membrane preparations. This suggests different but interdependent binding sites. Glucose uptake into everted sacs from rat intestine was stimulated by epinephrine and sugars in a β 2-AR-dependent manner. STD-NMR confirmed direct physical binding of glucose to the β 2-AR. Oral administration of glucose with a non-bioavailable β 2-AR antagonist lowered the subsequent increase in blood glucose levels, confirming a role for enterocyte apical β 2-ARs in stimulating gut glucose uptake, and suggesting enterocyte β 2-AR as novel drug target in diabetic and obese patients. Future work will have to reveal how glucose sensing by enterocytes and neuroendocrine cells is connected, and whether β 2-ARs mediate glucose sensing also in other tissues.
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Affiliation(s)
- Frederik Paulussen
- 1Center for Microbiology, VIB, Leuven-Heverlee, Belgium,2Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
| | - Chetan P. Kulkarni
- 1Center for Microbiology, VIB, Leuven-Heverlee, Belgium,3Functional Genomics and Proteomics Research Unit, Department of Biology, KU Leuven, Leuven, Belgium
| | - Frank Stolz
- 1Center for Microbiology, VIB, Leuven-Heverlee, Belgium,2Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
| | - Eveline Lescrinier
- 4Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Stijn De Graeve
- 1Center for Microbiology, VIB, Leuven-Heverlee, Belgium,2Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
| | - Suzan Lambin
- 1Center for Microbiology, VIB, Leuven-Heverlee, Belgium,2Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
| | | | | | - Peter In't Veld
- 6Department of Pathology, Free University of Brussels, Brussels, Belgium
| | - Joseph Mebis
- 7Department of Pathology, KU Leuven, Flanders, Belgium
| | - Jan Tavernier
- 8Department of Biochemistry, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium,9Center for Medical Biotechnology, VIB, Ghent, Belgium
| | - Patrick Van Dijck
- 1Center for Microbiology, VIB, Leuven-Heverlee, Belgium,2Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
| | - Walter Luyten
- 3Functional Genomics and Proteomics Research Unit, Department of Biology, KU Leuven, Leuven, Belgium
| | - Johan M. Thevelein
- 1Center for Microbiology, VIB, Leuven-Heverlee, Belgium,2Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium,10NovelYeast bv, Bio-Incubator BIO4, Gaston Geenslaan 3, Leuven-Heverlee,, Belgium,*Correspondence: Johan M. Thevelein,
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5
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Xie Y, Cai L, Huang Z, Shan K, Xu X, Zhou G, Li C. Plant-Based Meat Analogues Weaken Gastrointestinal Digestive Function and Show Less Digestibility Than Real Meat in Mice. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:12442-12455. [PMID: 36070521 DOI: 10.1021/acs.jafc.2c04246] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Real meat and plant-based meat analogues have different in vitro protein digestibility properties. This study aims to further explore their in vivo digestion and absorption and their effects on the gastrointestinal digestive function of mice. Compared with the real pork and beef, plant-based meat analogues significantly reduced the number of gastric parietal cells, the levels of gastrin/CCKBR, acetylcholine/AchR, Ca2+, CAMK II, PKC, and PKA, the activity of H+, K+-ATPase, and pepsin, the duodenal villus height, and the ratio of villus height to crypt depth and downregulated the expression of most nitrogen nutrient sensors. Peptidomics revealed that plant-based meat analogues released fewer peptides during in vivo digestion and increased the host- and microbial-derived peptides. Moreover, the real beef showed better absorption properties. These results suggested that plant-based meat analogues weaken gastrointestinal digestive function of mice, and their digestion and absorption performance in vivo is not as good as the real meat.
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Affiliation(s)
- Yunting Xie
- Key Laboratory of Meat Processing and Quality Control, MOE; Key Laboratory of Meat Processing, MARA; Jiangsu Innovative Center of Meat Production, Processing and Quality Control; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Linlin Cai
- Key Laboratory of Meat Processing and Quality Control, MOE; Key Laboratory of Meat Processing, MARA; Jiangsu Innovative Center of Meat Production, Processing and Quality Control; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhiji Huang
- Key Laboratory of Meat Processing and Quality Control, MOE; Key Laboratory of Meat Processing, MARA; Jiangsu Innovative Center of Meat Production, Processing and Quality Control; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Kai Shan
- Key Laboratory of Meat Processing and Quality Control, MOE; Key Laboratory of Meat Processing, MARA; Jiangsu Innovative Center of Meat Production, Processing and Quality Control; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Xinglian Xu
- Key Laboratory of Meat Processing and Quality Control, MOE; Key Laboratory of Meat Processing, MARA; Jiangsu Innovative Center of Meat Production, Processing and Quality Control; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Guanghong Zhou
- Key Laboratory of Meat Processing and Quality Control, MOE; Key Laboratory of Meat Processing, MARA; Jiangsu Innovative Center of Meat Production, Processing and Quality Control; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Chunbao Li
- Key Laboratory of Meat Processing and Quality Control, MOE; Key Laboratory of Meat Processing, MARA; Jiangsu Innovative Center of Meat Production, Processing and Quality Control; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
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6
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Watkins JD, Koumanov F, Gonzalez JT. Protein- and Calcium-Mediated GLP-1 Secretion: A Narrative Review. Adv Nutr 2021; 12:2540-2552. [PMID: 34192748 PMCID: PMC8634310 DOI: 10.1093/advances/nmab078] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/31/2021] [Accepted: 05/25/2021] [Indexed: 02/06/2023] Open
Abstract
Glucagon-like peptide 1 (GLP-1) is an incretin hormone produced in the intestine that is secreted in response to nutrient exposure. GLP-1 potentiates glucose-dependent insulin secretion from the pancreatic β cells and promotes satiety. These important actions on glucose metabolism and appetite have led to widespread interest in GLP-1 receptor agonism. Typically, this involves pharmacological GLP-1 mimetics or targeted inhibition of dipeptidyl peptidase-IV, the enzyme responsible for GLP-1 degradation. However, nutritional strategies provide a widely available, cost-effective alternative to pharmacological strategies for enhancing hormone release. Recent advances in nutritional research have implicated the combined ingestion of protein and calcium with enhanced endogenous GLP-1 release, which is likely due to activation of receptors with high affinity and/or sensitivity for amino acids and calcium. Specifically targeting these receptors could enhance gut hormone secretion, thus providing a new therapeutic option. This narrative review provides an overview of the latest research on protein- and calcium-mediated GLP-1 release with an emphasis on human data, and a perspective on potential mechanisms that link potent GLP-1 release to the co-ingestion of protein and calcium. In light of these recent findings, potential future research directions are also presented.
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Affiliation(s)
- Jonathan D Watkins
- Centre for Nutrition, Exercise and Metabolism, Department for Health, University of Bath, Bath, United Kingdom
| | - Françoise Koumanov
- Centre for Nutrition, Exercise and Metabolism, Department for Health, University of Bath, Bath, United Kingdom
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7
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Mikołajczyk-Stecyna J, Malinowska AM, Mlodzik-Czyzewska M, Chmurzynska A. Coffee and tea choices and intake patterns in 20-to-40 year old adults. Food Qual Prefer 2021. [DOI: 10.1016/j.foodqual.2020.104115] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Macronutrient Sensing in the Oral Cavity and Gastrointestinal Tract: Alimentary Tastes. Nutrients 2021; 13:nu13020667. [PMID: 33669584 PMCID: PMC7922037 DOI: 10.3390/nu13020667] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/09/2021] [Accepted: 02/16/2021] [Indexed: 02/07/2023] Open
Abstract
There are numerous and diverse factors enabling the overconsumption of foods, with the sense of taste being one of these factors. There are four well established basic tastes: sweet, sour, salty, and bitter; all with perceptual independence, salience, and hedonic responses to encourage or discourage consumption. More recently, additional tastes have been added to the basic taste list including umami and fat, but they lack the perceptual independence and salience of the basics. There is also emerging evidence of taste responses to kokumi and carbohydrate. One interesting aspect is the link with the new and emerging tastes to macronutrients, with each macronutrient having two distinct perceptual qualities that, perhaps in combination, provide a holistic perception for each macronutrient: fat has fat taste and mouthfeel; protein has umami and kokumi; carbohydrate has sweet and carbohydrate tastes. These new tastes can be sensed in the oral cavity, but they have more influence post- than pre-ingestion. Umami, fat, kokumi, and carbohydrate tastes have been suggested as an independent category named alimentary. This narrative review will present and discuss evidence for macronutrient sensing throughout the alimentary canal and evidence of how each of the alimentary tastes may influence the consumption of foods.
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9
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Saidi K, Nilholm C, Roth B, Ohlsson B. A carbohydrate-restricted diet for patients with irritable bowel syndrome lowers serum C-peptide, insulin, and leptin without any correlation with symptom reduction. Nutr Res 2020; 86:23-36. [PMID: 33450656 DOI: 10.1016/j.nutres.2020.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 11/26/2020] [Accepted: 12/01/2020] [Indexed: 12/19/2022]
Abstract
Alterations in gut endocrine cells and hormone levels have been measured in patients with irritable bowel syndrome (IBS). The hypothesis of the present study was that hormone levels would change after 4 weeks of a starch- and sucrose-reduced diet (SSRD) intervention corresponding to decreased carbohydrate intake and symptoms. Among 105 IBS patients from primary and tertiary healthcare, 80 were randomized to SSRD, while 25 followed their ordinary diet. Food diaries, Rome IV, and IBS-symptom severity score (IBS-SSS) questionnaires were completed, and blood samples were collected at baseline and after the intervention. Serum C-peptide, gastric inhibitory peptide, glucagon, glucagon-like peptide-1, insulin, leptin, luteinizing hormone, polypeptide YY, and glucose were measured, along with the prevalence of autoantibodies against gonadotropin-releasing hormone; its precursor, progonadoliberin-2, and receptor; and tenascin C. Carbohydrate intake was lower in the intervention group than in controls at week 4 (median: 88 [66-128] g vs 182 [89-224] g; P < .001). The change in carbohydrate intake, adjusted for weight, was associated with a decrease in C-peptide (β: 14.43; 95% confidence interval [CI]: 4.12-24.75) and insulin (β: 0.18; 95% CI: 0.04-0.32) levels. Glucose levels remained unchanged. The IBS-SSS scores were lower in the intervention group but not in controls (P < .001), without any association with changes in hormone concentrations. There was no difference in autoantibody prevalence between patients and healthy controls. In conclusion, the hypothesis that reduced carbohydrate intake corresponded to altered hormonal levels in IBS was accepted; however, there was no relationship between hormonal concentrations and symptoms.
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Affiliation(s)
- Khadija Saidi
- Lund University, Skåne University Hospital Malmö, Department of Internal Medicine, Malmö, Sweden.
| | - Clara Nilholm
- Lund University, Skåne University Hospital Malmö, Department of Internal Medicine, Malmö, Sweden.
| | - Bodil Roth
- Lund University, Skåne University Hospital Malmö, Department of Internal Medicine, Malmö, Sweden.
| | - Bodil Ohlsson
- Lund University, Skåne University Hospital Malmö, Department of Internal Medicine, Malmö, Sweden.
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10
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Nunez-Salces M, Li H, Feinle-Bisset C, Young RL, Page AJ. Nutrient-sensing components of the mouse stomach and the gastric ghrelin cell. Neurogastroenterol Motil 2020; 32:e13944. [PMID: 32666613 DOI: 10.1111/nmo.13944] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/22/2020] [Accepted: 06/22/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND The ability of the gut to detect nutrients is critical to the regulation of gut hormone secretion, food intake, and postprandial blood glucose control. Ingested nutrients are detected by specific gut chemosensors. However, knowledge of these chemosensors has primarily been derived from the intestine, while available information on gastric chemosensors is limited. This study aimed to investigate the nutrient-sensing repertoire of the mouse stomach with particular emphasis on ghrelin cells. METHODS Quantitative RT-PCR was used to determine mRNA levels of nutrient chemosensors (protein: G protein-coupled receptor 93 [GPR93], calcium-sensing receptor [CaSR], metabotropic glutamate receptor type 4 [mGluR4]; fatty acids: CD36, FFAR2&4; sweet/umami taste: T1R3), taste transduction components (TRPM5, GNAT2&3), and ghrelin and ghrelin-processing enzymes (PC1/3, ghrelin O-acyltransferase [GOAT]) in the gastric corpus and antrum of adult male C57BL/6 mice. Immunohistochemistry was performed to assess protein expression of chemosensors (GPR93, T1R3, CD36, and FFAR4) and their co-localization with ghrelin. KEY RESULTS Most nutrient chemosensors had higher mRNA levels in the antrum compared to the corpus, except for CD36, GNAT2, ghrelin, and GOAT. Similar regional distribution was observed at the protein level. At least 60% of ghrelin-positive cells expressed T1R3 and FFAR4, and over 80% expressed GPR93 and CD36. CONCLUSIONS AND INFERENCES The cellular mechanisms for the detection of nutrients are expressed in a region-specific manner in the mouse stomach and gastric ghrelin cells. These gastric nutrient chemosensors may play a role modulating gastrointestinal responses, such as the inhibition of ghrelin secretion following food intake.
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Affiliation(s)
- Maria Nunez-Salces
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Nutrition, Diabetes & Gut Health, Lifelong Health Theme, South Australian Health & Medical Research Institute (SAHMRI), Adelaide, SA, Australia
| | - Hui Li
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Nutrition, Diabetes & Gut Health, Lifelong Health Theme, South Australian Health & Medical Research Institute (SAHMRI), Adelaide, SA, Australia
| | - Christine Feinle-Bisset
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - Richard L Young
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Nutrition, Diabetes & Gut Health, Lifelong Health Theme, South Australian Health & Medical Research Institute (SAHMRI), Adelaide, SA, Australia.,Intestinal Nutrient Sensing Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - Amanda J Page
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Nutrition, Diabetes & Gut Health, Lifelong Health Theme, South Australian Health & Medical Research Institute (SAHMRI), Adelaide, SA, Australia
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11
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Koepsell H. Glucose transporters in the small intestine in health and disease. Pflugers Arch 2020; 472:1207-1248. [PMID: 32829466 PMCID: PMC7462918 DOI: 10.1007/s00424-020-02439-5] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 07/11/2020] [Accepted: 07/17/2020] [Indexed: 12/23/2022]
Abstract
Absorption of monosaccharides is mainly mediated by Na+-D-glucose cotransporter SGLT1 and the facititative transporters GLUT2 and GLUT5. SGLT1 and GLUT2 are relevant for absorption of D-glucose and D-galactose while GLUT5 is relevant for D-fructose absorption. SGLT1 and GLUT5 are constantly localized in the brush border membrane (BBM) of enterocytes, whereas GLUT2 is localized in the basolateral membrane (BLM) or the BBM plus BLM at low and high luminal D-glucose concentrations, respectively. At high luminal D-glucose, the abundance SGLT1 in the BBM is increased. Hence, D-glucose absorption at low luminal glucose is mediated via SGLT1 in the BBM and GLUT2 in the BLM whereas high-capacity D-glucose absorption at high luminal glucose is mediated by SGLT1 plus GLUT2 in the BBM and GLUT2 in the BLM. The review describes functions and regulations of SGLT1, GLUT2, and GLUT5 in the small intestine including diurnal variations and carbohydrate-dependent regulations. Also, the roles of SGLT1 and GLUT2 for secretion of enterohormones are discussed. Furthermore, diseases are described that are caused by malfunctions of small intestinal monosaccharide transporters, such as glucose-galactose malabsorption, Fanconi syndrome, and fructose intolerance. Moreover, it is reported how diabetes, small intestinal inflammation, parental nutrition, bariatric surgery, and metformin treatment affect expression of monosaccharide transporters in the small intestine. Finally, food components that decrease D-glucose absorption and drugs in development that inhibit or downregulate SGLT1 in the small intestine are compiled. Models for regulations and combined functions of glucose transporters, and for interplay between D-fructose transport and metabolism, are discussed.
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Affiliation(s)
- Hermann Koepsell
- Institute for Anatomy and Cell Biology, University of Würzburg, Koellikerstr 6, 97070, Würzburg, Germany.
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12
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Shannon M, Xie Y, Verhaegen S, Wilson J, Berntsen HF, Zimmer KE, Ropstad E, Green BD, Connolly L. A Human Relevant Defined Mixture of Persistent Organic Pollutants (POPs) Affects In Vitro Secretion of Glucagon-Like Peptide 1 (GLP-1), but Does Not Affect Translocation of Its Receptor. Toxicol Sci 2020; 172:359-367. [PMID: 31432086 DOI: 10.1093/toxsci/kfz192] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Environmental exposure to persistent organic pollutants (POPs) has been suggested as a contributing factor for the increased rate of type 2 diabetes and obesity. A complex mixture of 29 POPs (Total mixture), based on human blood concentrations, was used to expose a glucagon-like peptide 1 (GLP-1) secreting enteroendocrine cell line (pGIP/neo: STC-1) in vitro for 3 and 24 h. Significant increases of GLP-1 occurred when cells were exposed to the Total mixture at ×500 blood levels. Six sub-mixtures representing chlorinated (Cl), brominated (Br), and perfluorinated chemicals (PFAA), and their combinations (Cl + Br, Cl + PFAA, Br + PFAA) were also tested at ×500. Secretion levels seen for these remained lower than the Total mixture, and the Br mixture had no effect. After 24 h, increased secretion was seen with all mixtures at ×1 blood levels. Cytotoxicity was present for ×100 and ×500 blood levels. When tested in a GLP-1 receptor translocation assay (U2OS-GLP1R-EGFP), neither agonistic nor antagonist effects on receptor internalization were seen for any of the mixtures. We conclude individual classes of POPs, alone or in combination, can affect GLP-1 secretion and may contribute as a molecular mechanism linking environmental toxicants and diabetes.
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Affiliation(s)
- Maeve Shannon
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, Northern Ireland, UK
| | - Yuling Xie
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, Northern Ireland, UK
| | - Steven Verhaegen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo 0102, Norway
| | - Jodie Wilson
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, Northern Ireland, UK
| | - Hanne F Berntsen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo 0102, Norway.,Department of Administration, Lab Animal Unit, National Institute of Occupational Health, Oslo 0363, Norway
| | - Karin E Zimmer
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo 0102, Norway
| | - Erik Ropstad
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo 0102, Norway
| | - Brian D Green
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, Northern Ireland, UK
| | - Lisa Connolly
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, Northern Ireland, UK
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13
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Gastrointestinally Digested Protein from the Insect Alphitobius diaperinus Stimulates a Different Intestinal Secretome than Beef or Almond, Producing a Differential Response in Food Intake in Rats. Nutrients 2020; 12:nu12082366. [PMID: 32784756 PMCID: PMC7468914 DOI: 10.3390/nu12082366] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 07/31/2020] [Accepted: 08/06/2020] [Indexed: 12/21/2022] Open
Abstract
In this study we compare the interaction of three protein sources—insect, beef, and almond—with the gastrointestinal tract. We measured the enterohormone secretion ex vivo in human and pig intestine treated with in vitro digestions of these foods. Insect and beef were the most effective in inducing the secretion of CCK, while almond was the most effective in inducing PYY in pig duodenum. In the human colon, almond was also the most effective in inducing PYY, and GLP-1 levels were increased by insect and beef. The three digested proteins reduced ghrelin secretion in pig duodenum, while only insect reduced ghrelin secretion in human colon. We also found that food intake in rats increased in groups fed a raw insect pre-load and decreased when fed raw almond. In conclusion, the insect Alphitobius diaperinus modulates duodenal and colonic enterohormone release and increases food intake in rats. These effects differ from beef and almond.
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14
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Raka F, Farr S, Kelly J, Stoianov A, Adeli K. Metabolic control via nutrient-sensing mechanisms: role of taste receptors and the gut-brain neuroendocrine axis. Am J Physiol Endocrinol Metab 2019; 317:E559-E572. [PMID: 31310579 DOI: 10.1152/ajpendo.00036.2019] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Nutrient sensing plays an important role in ensuring that appropriate digestive or hormonal responses are elicited following the ingestion of fuel substrates. Mechanisms of nutrient sensing in the oral cavity have been fairly well characterized and involve lingual taste receptors. These include heterodimers of G protein-coupled receptors (GPCRs) of the taste receptor type 1 (T1R) family for sensing sweet (T1R2-T1R3) and umami (T1R1-T1R3) stimuli, the T2R family for sensing bitter stimuli, and ion channels for conferring sour and salty tastes. In recent years, several studies have revealed the existence of additional nutrient-sensing mechanisms along the gastrointestinal tract. Glucose sensing is achieved by the T1R2-T1R3 heterodimer on enteroendocrine cells, which plays a role in triggering the secretion of incretin hormones for improved glycemic and lipemic control. Protein hydrolysates are detected by Ca2+-sensing receptor, the T1R1-T1R3 heterodimer, and G protein-coupled receptor 92/93 (GPR92/93), which leads to the release of the gut-derived satiety factor cholecystokinin. Furthermore, several GPCRs have been implicated in fatty acid sensing: GPR40 and GPR120 respond to medium- and long-chain fatty acids, GPR41 and GPR43 to short-chain fatty acids, and GPR119 to endogenous lipid derivatives. Aside from the recognition of fuel substrates, both the oral cavity and the gastrointestinal tract also possess T2R-mediated mechanisms of recognizing nonnutrients such as environmental contaminants, bacterial toxins, and secondary plant metabolites that evoke a bitter taste. These gastrointestinal sensing mechanisms result in the transmission of neuronal signals to the brain through the release of gastrointestinal hormones that act on vagal and enteric afferents to modulate the physiological response to nutrients, particularly satiety and energy homeostasis. Modulating these orally accessible nutrient-sensing pathways using particular foods, dietary supplements, or pharmaceutical compounds may have therapeutic potential for treating obesity and metabolic diseases.
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Affiliation(s)
- Fitore Raka
- Molecular Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Sarah Farr
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Jacalyn Kelly
- Molecular Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Alexandra Stoianov
- Molecular Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Khosrow Adeli
- Molecular Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
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15
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Powley TL, Jaffey DM, McAdams J, Baronowsky EA, Black D, Chesney L, Evans C, Phillips RJ. Vagal innervation of the stomach reassessed: brain-gut connectome uses smart terminals. Ann N Y Acad Sci 2019; 1454:14-30. [PMID: 31268562 DOI: 10.1111/nyas.14138] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/07/2019] [Accepted: 05/16/2019] [Indexed: 01/06/2023]
Abstract
Brain-gut neural communications have long been considered limited because of conspicuous numerical mismatches. The vagus, the parasympathetic nerve connecting brain and gut, contains thousands of axons, whereas the gastrointestinal (GI) tract contains millions of intrinsic neurons in local plexuses. The numerical paradox was initially recognized in terms of efferent projections, but the number of afferents, which comprise the majority (≈ 80%) of neurites in the vagus, is also relatively small. The present survey of recent morphological observations suggests that vagal terminals, and more generally autonomic and visceral afferent arbors in the stomach as well as throughout the gut, elaborate arbors that are extensive, regionally specialized, polymorphic, polytopic, and polymodal, commonly with multiplicities of receptors and binding sites-smart terminals. The morphological specializations and dynamic tuning of one-to-many efferent projections and many-to-one convergences of contacts onto afferents create a complex architecture capable of extensive peripheral integration in the brain-gut connectome and offset many of the disparities between axon and target numbers. Appreciating this complex architecture can help in the design of therapies for GI disorders.
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Affiliation(s)
- Terry L Powley
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
| | - Deborah M Jaffey
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
| | - Jennifer McAdams
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
| | - Elizabeth A Baronowsky
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
| | - Diana Black
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
| | - Logan Chesney
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
| | - Charlene Evans
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
| | - Robert J Phillips
- Behavioral Neuroscience Area, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana
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16
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Modvig IM, Kuhre RE, Holst JJ. Peptone-mediated glucagon-like peptide-1 secretion depends on intestinal absorption and activation of basolaterally located Calcium-Sensing Receptors. Physiol Rep 2019; 7:e14056. [PMID: 31020803 PMCID: PMC6482282 DOI: 10.14814/phy2.14056] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/15/2019] [Accepted: 03/16/2019] [Indexed: 01/13/2023] Open
Abstract
Protein intake robustly stimulates the secretion of the incretin hormone, glucagon-like peptide-1 (GLP-1) but the molecular mechanisms involved are not well understood. In particular, it is unknown whether proteins stimulate secretion by activation of luminal or basolateral sensors. We characterized the mechanisms using a physiologically relevant model - the isolated perfused proximal rat small intestine. Intraluminal protein hydrolysates derived from meat (peptone; 50 mg/mL) increased GLP-1 secretion 2.3-fold (from a basal secretion of 110 ± 28 fmol/min). The sensory mechanisms underlying the response depended on di/tripeptide uptake through Peptide Transporter 1 (PepT1) and subsequent basolateral activation of the amino acid sensing receptor, Calcium-Sensing Receptor (CaSR), since inhibition of PepT1 as well as CaSR both attenuated the peptone-induced GLP-1 response. Supporting this, intraluminal peptones were absorbed efficiently by the perfused intestine (resulting in increased amino acid concentrations in the venous effluent) and infusion of amino acids robustly stimulated GLP-1 secretion. Inhibitors of voltage-gated L-type Ca2+ channels had no effect on secretion suggesting that peptone-mediated GLP-1 secretion is not mediated by L-cell depolarization with subsequent opening of these channels. Specific targeting of CaSR could serve as a target to stimulate the endogenous secretion of GLP-1.
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Affiliation(s)
- Ida M. Modvig
- Department of Biomedical SciencesNNF Center for Basic Metabolic ResearchFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Rune E. Kuhre
- Department of Biomedical SciencesNNF Center for Basic Metabolic ResearchFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Jens Juul Holst
- Department of Biomedical SciencesNNF Center for Basic Metabolic ResearchFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
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17
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Scopelliti A, Bauer C, Yu Y, Zhang T, Kruspig B, Murphy DJ, Vidal M, Maddocks ODK, Cordero JB. A Neuronal Relay Mediates a Nutrient Responsive Gut/Fat Body Axis Regulating Energy Homeostasis in Adult Drosophila. Cell Metab 2019; 29:269-284.e10. [PMID: 30344016 PMCID: PMC6370946 DOI: 10.1016/j.cmet.2018.09.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 08/10/2018] [Accepted: 09/25/2018] [Indexed: 02/05/2023]
Abstract
The control of systemic metabolic homeostasis involves complex inter-tissue programs that coordinate energy production, storage, and consumption, to maintain organismal fitness upon environmental challenges. The mechanisms driving such programs are largely unknown. Here, we show that enteroendocrine cells in the adult Drosophila intestine respond to nutrients by secreting the hormone Bursicon α, which signals via its neuronal receptor DLgr2. Bursicon α/DLgr2 regulate energy metabolism through a neuronal relay leading to the restriction of glucagon-like, adipokinetic hormone (AKH) production by the corpora cardiaca and subsequent modulation of AKH receptor signaling within the adipose tissue. Impaired Bursicon α/DLgr2 signaling leads to exacerbated glucose oxidation and depletion of energy stores with consequent reduced organismal resistance to nutrient restrictive conditions. Altogether, our work reveals an intestinal/neuronal/adipose tissue inter-organ communication network that is essential to restrict the use of energy and that may provide insights into the physiopathology of endocrine-regulated metabolic homeostasis.
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Affiliation(s)
| | - Christin Bauer
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Yachuan Yu
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Tong Zhang
- Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1QH, UK
| | - Björn Kruspig
- Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1QH, UK
| | - Daniel J Murphy
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK; Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1QH, UK
| | - Marcos Vidal
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Oliver D K Maddocks
- Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1QH, UK
| | - Julia B Cordero
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK; Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1QH, UK.
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18
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Lyte JM. Eating for 3.8 × 10 13: Examining the Impact of Diet and Nutrition on the Microbiota-Gut-Brain Axis Through the Lens of Microbial Endocrinology. Front Endocrinol (Lausanne) 2019; 9:796. [PMID: 30761092 PMCID: PMC6361751 DOI: 10.3389/fendo.2018.00796] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 12/19/2018] [Indexed: 12/30/2022] Open
Abstract
The study of host-microbe neuroendocrine crosstalk, termed microbial endocrinology, suggests the impact of diet on host health and microbial viability is, in part, reliant upon nutritional modulation of shared host-microbe neuroendocrine axes. In the 1990's it was first recognized that neuroendocrine pathways are major components of the microbiota-gut-brain axis, and that diet-induced changes in the gut microbiota were correlated with changes in host behavior and cognition. A causative link, however, between nutritional-induced shifts in microbiota composition and change in host behavior has yet to be fully elucidated. Substrates found in food which are utilized by bacteria in the production of microbial-derived neurochemicals, which are structurally identical to those made by the host, likely represent a microbial endocrinology-based route by which the microbiota causally influence the host and microbial community dynamics via diet. For example, food safety is strongly impacted by the microbial production of biogenic amines. While microbial-produced tyramine found in cheese can elicit hypertensive crises, microorganisms which are common inhabitants of the human intestinal tract can convert L-histidine found in common foodstuffs to histamine and thereby precipitate allergic reactions. Hence, there is substantial evidence suggesting a microbial endocrinology-based role by which the gastrointestinal microbiota can utilize host dietary components to produce neuroactive molecules that causally impact the host. Conversely, little is known regarding the reverse scenario whereby nutrition-mediated changes in host neuroendocrine production affect microbial viability, composition, and/or function. Mechanisms in the direction of brain-to-gut, such as how host production of catecholamines drives diverse changes in microbial growth and functionality within the gut, require greater examination considering well-known nutritional effects on host stress physiology. As dietary intake mediates changes in host stress, such as the effects of caffeine on the hypothalamic-pituitary-adrenal axis, it is likely that nutrition can impact host neuroendocrine production to affect the microbiota. Likewise, the plasticity of the microbiota to changes in host diet has been hypothesized to drive microbial regulation of host food preference via a host-microbe feedback loop. This review will focus on food as concerns microbial endocrinology with emphasis given to nutrition as a mediator of host-microbe bi-directional neuroendocrine crosstalk and its impact on microbial viability and host health.
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Affiliation(s)
- Joshua M. Lyte
- Poultry Production and Product Safety Research Unit, Agricultural Research Service, United States Department of Agriculture, Fayetteville, AR, United States
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19
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Abstract
Neurolocalization of taste disorders requires a knowledge of the functional anatomy involved in mediating taste information from the peripheral mucosal surfaces through numerous peripheral cranial nerves to complex subcortical and cortical brain regions. Our understanding of this functional anatomy has advanced in recent years. Taste is an experience that is both innate and learned, and the "taste" experience involves the integration of information from other sensory modalities, such as olfaction and somatosensation. Normal taste perception is influenced by different neurophysiologic states, which involve endocrine function, emotions, and even attitudes and expectations toward eating. At its core, the normal effective ability to taste is a reflection of the proper function of many organ systems within the body and may be considered a marker for good health. Clinical taste disorders, on the other hand, involve the dysfunction of the normal neural taste pathways and/or aberrant influences on multisensory integration and cortical taste processing. The number of disease processes, which can adversely affect taste, are numerous and quite varied in their presentation. There may be contributory involvement of other organ systems within the body, and the appropriate management of taste disorders often requires a multidisciplinary approach to fully understand the disorder. Depending on the underlying cause, taste disorders can be effectively managed when identified. Treatments may include correcting underlying metabolic disturbances, eliminating infections, changing offending medications, replenishing nutritional deficiencies, operating on structural impairments, calming autoimmune processes, and even stabilizing electrochemical interactions.
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Affiliation(s)
- Steven M Bromley
- South Jersey MS Center and Bromley Neurology, PC, Audubon, NJ, United States.
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20
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Postnatal differential expression of chemoreceptors of free fatty acids along the gastrointestinal tract of supplemental feeding v. grazing kid goats. Animal 2019; 13:509-517. [DOI: 10.1017/s1751731118001581] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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21
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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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22
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Zhao X, Xian Y, Wang C, Ding L, Meng X, Zhu W, Hang S. Calcium-sensing receptor-mediated L-tryptophan-induced secretion of cholecystokinin and glucose-dependent insulinotropic peptide in swine duodenum. J Vet Sci 2018; 19:179-187. [PMID: 29284209 PMCID: PMC5879066 DOI: 10.4142/jvs.2018.19.2.179] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 12/17/2017] [Accepted: 12/26/2017] [Indexed: 12/31/2022] Open
Abstract
This study aimed to elucidate the effect of tryptophan (Trp) on gut hormone secretion as well as the roles of the calcium-sensing receptor (CaSR) and its downstream signaling pathway in gut hormone secretion by assessing swine duodenal perfusion in vitro. Swine duodenum was perfused with Krebs-Henseleit buffer as a basal solution. Various concentrations (0, 10, and 20 mM) of Trp were applied to investigate its effect on gut hormone secretion. A CaSR antagonist was used to detect the involvement of CaSR and its signal molecules. The 20 mM Trp concentration promoted the secretion of cholecystokinin (CCK) and glucose-dependent insulinotropic peptide (GIP), elevated the mRNA level of CaSR, and upregulated the protein levels of CaSR, protein kinase C (PKC), and inositol trisphosphate receptor (IP3R). However, NPS 2143, an inhibitor of CaSR, attenuated the CCK and GIP release, reduced the mRNA level of CaSR, and decreased the protein levels of CaSR, PKC, and IP3R with 20 mM Trp perfusion. The results indicate that CCK and GIP secretion can be induced by Trp in swine duodenum in vitro, and the effect is mediated by CaSR and its downstream signal molecules PKC and IP3R.
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Affiliation(s)
- Xiuying Zhao
- Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China
| | - Yihan Xian
- Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China
| | - Chao Wang
- Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China
| | - Liren Ding
- Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China
| | - Xianglong Meng
- Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China
| | - Weiyun Zhu
- Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China
| | - Suqin Hang
- Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China
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23
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Miller HC, Struyf D, Baptist P, Dalile B, Van Oudenhove L, Van Diest I. A mind cleared by walnut oil: The effects of polyunsaturated and saturated fat on extinction learning. Appetite 2018; 126:147-155. [PMID: 29634989 DOI: 10.1016/j.appet.2018.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/06/2018] [Accepted: 04/06/2018] [Indexed: 12/31/2022]
Abstract
The treatment of anxiety-based psychopathology often hinges upon extinction learning. Research in nutritional neuroscience has observed that the regular consumption of perilla oil (50% alpha-linolenic acid (ALA)) facilitates extinction learning in rats (Yamamoto et al., 1988). However, acute facilitation of extinction learning by oils rich in ALA has not been reported for rats or humans, though the acute consumption of rapeseed oil (10% ALA) has been observed to improve cognitive processing speed in humans (Jones, Sünram-Lea, & Wesnes, 2012). For this reason, the present laboratory work examined the effects of adding walnut oil (12% ALA) to a chocolate milkshake on the acquisition, generalization, and extinction of a fear-based prediction in young adults. It compared performance between subjects. The other participants consumed a similar milkshake with either an equicaloric amount of cream (saturated fat), or with no added fat (control). Acquisition and generalization of the fear-based prediction were similar for all groups. However, those who consumed walnut oil extinguished most rapidly and profoundly. Implications for extinction learning are discussed.
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Affiliation(s)
| | - Dieter Struyf
- KULeuven, Health, Behavior and Psychopathology, Belgium
| | | | - Boushra Dalile
- KULeuven, Translational Research in GastroIntestinal Disorders, Belgium
| | | | - Ilse Van Diest
- KULeuven, Health, Behavior and Psychopathology, Belgium.
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Haluzík M, Kratochvílová H, Haluzíková D, Mráz M. Gut as an emerging organ for the treatment of diabetes: focus on mechanism of action of bariatric and endoscopic interventions. J Endocrinol 2018; 237:R1-R17. [PMID: 29378901 DOI: 10.1530/joe-17-0438] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 01/29/2018] [Indexed: 01/19/2023]
Abstract
Increasing worldwide prevalence of type 2 diabetes mellitus and its accompanying pathologies such as obesity, arterial hypertension and dyslipidemia represents one of the most important challenges of current medicine. Despite intensive efforts, high percentage of patients with type 2 diabetes does not achieve treatment goals and struggle with increasing body weight and poor glucose control. While novel classes of antidiabetic medications such as incretin-based therapies and gliflozins have some favorable characteristics compared to older antidiabetics, the only therapeutic option shown to substantially modify the progression of diabetes or to achieve its remission is bariatric surgery. Its efficacy in the treatment of diabetes is well established, but the exact underlying modes of action are still only partially described. They include restriction of food amount, enhanced passage of chymus into distal part of small intestine with subsequent modification of gastrointestinal hormones and bile acids secretion, neural mechanisms, changes in gut microbiota and many other possible mechanisms underscoring the importance of the gut in the regulation of glucose metabolism. In addition to bariatric surgery, less-invasive endoscopic methods based on the principles of bariatric surgery were introduced and showed promising results. This review highlights the role of the intestine in the regulation of glucose homeostasis focusing on the mechanisms of action of bariatric and especially endoscopic methods of the treatment of diabetes. A better understanding of these mechanisms may lead to less invasive endoscopic treatments of diabetes and obesity that may complement and widen current therapeutic options.
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Affiliation(s)
- Martin Haluzík
- Centre for Experimental MedicineInstitute for Clinical and Experimental Medicine, Prague, Czech Republic
- Diabetes CentreInstitute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Medical Biochemistry and Laboratory DiagnosticsGeneral University Hospital, Charles University in Prague, 1st Faculty of Medicine, Prague, Czech Republic
| | - Helena Kratochvílová
- Centre for Experimental MedicineInstitute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Medical Biochemistry and Laboratory DiagnosticsGeneral University Hospital, Charles University in Prague, 1st Faculty of Medicine, Prague, Czech Republic
| | - Denisa Haluzíková
- Department of Sports MedicineGeneral University Hospital, Charles University in Prague, 1st Faculty of Medicine, Prague, Czech Republic
| | - Miloš Mráz
- Diabetes CentreInstitute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Medical Biochemistry and Laboratory DiagnosticsGeneral University Hospital, Charles University in Prague, 1st Faculty of Medicine, Prague, Czech Republic
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Zanchi D, Meyer-Gerspach AC, Schmidt A, Suenderhauf C, Depoorter A, Drewe J, Beglinger C, Wölnerhanssen BK, Borgwardt S. Acute Effects of Glucose and Fructose Administration on the Neural Correlates of Cognitive Functioning in Healthy Subjects: A Pilot Study. Front Psychiatry 2018; 9:71. [PMID: 29593582 PMCID: PMC5857887 DOI: 10.3389/fpsyt.2018.00071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 02/21/2018] [Indexed: 01/27/2023] Open
Abstract
The present randomized double-blinded cross-over study aims to extensively study the neural correlates underpinning cognitive functions in healthy subjects after acute glucose and fructose administration, using an integrative multimodal neuroimaging approach. Five minutes after glucose, fructose, or placebo administration through a nasogastric tube, 12 participants underwent 3 complementary neuroimaging techniques: 2 task-based functional magnetic resonance imaging (fMRI) sequences to assess working memory (N-back) and response inhibition (Go/No-Go) and one resting state fMRI sequence to address the cognition-related fronto-parietal network (FPN) and salience network (SN). During working memory processing, glucose intake decreased activation in the anterior cingulate cortex (ACC) relative to placebo, while fructose decreased activation in the ACC and sensory cortex relative to placebo and glucose. During response inhibition, glucose and fructose decreased activation in the ACC, insula and visual cortex relative to placebo. Resting state fMRI indicated increased global connectivity strength of the FPN and the SN during glucose and fructose intake. The results demonstrate that glucose and fructose lead to partially different partially overlapping changes in regional brain activities that underpin cognitive performance in different tasks.
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Affiliation(s)
- Davide Zanchi
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland
| | | | - André Schmidt
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland
| | | | - Antoinette Depoorter
- Division of Neuropediatrics and Developmental Medicine, University Children's Hospital, Basel, Switzerland
| | - Jürgen Drewe
- Department of Biomedicine, University Hospital Basel, Basel, Switzerland
| | | | - Bettina Karin Wölnerhanssen
- Department of Research, St. Clara Hospital, Basel, Switzerland.,Department of Biomedicine, University Hospital Basel, Basel, Switzerland
| | - Stefan Borgwardt
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland
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Pereira RT, de Freitas TR, de Oliveira IRC, Costa LS, Vigliano FA, Rosa PV. Endocrine cells producing peptide hormones in the intestine of Nile tilapia: distribution and effects of feeding and fasting on the cell density. FISH PHYSIOLOGY AND BIOCHEMISTRY 2017; 43:1399-1412. [PMID: 28501979 DOI: 10.1007/s10695-017-0380-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 04/27/2017] [Indexed: 06/07/2023]
Abstract
Endocrine cells (ECs) act as a luminal surveillance system responding to either the presence or absence of food in the gut through the secretion of peptide hormones. The aim of this study was to analyze the effects of feeding and fasting on the EC peptide-specific distribution along the intestine of Nile tilapia. We assessed the density of ECs producing gastrin (GAS), cholecystokinin-8 (CCK-8), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP) in nine segments of the intestine using immunohistochemistry. Our results show that ECs immunoreactive to CCK-8, GAS, NPY, and CGRP can be found along all the intestinal segments sampled, from the midgut to hindgut, although differences in their distribution along the gut were observed. Regarding nutrient status, we found that the anterior segments of the midgut seem to be the main site responding to luminal changes in Nile tilapia. The NPY+ and CGRP+ EC densities increased in the fasted group, while the amount of CCK-8+ ECs were higher in the fed group. No effects of fasting or feeding were found in the GAS+ EC densities. Changes in ECs density were found only at the anterior segments of the intestine which may be due to the correlation between vagus nerve anatomy, EC location, and peptide turnover. Lastly, ECs may need to be considered an active cell subpopulation that may adapt and respond to different nutrient status as stimuli. Due to the complexity of the enteroendocrine system and its importance in fish nutrition, much remains to be elucidated and it deserves closer attention.
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Affiliation(s)
- Raquel Tatiane Pereira
- Department of Animal Science, Federal University of Lavras UFLA, Lavras, Minas Gerais, 37200-000, Brazil.
- Cátedra de Histología y Embriología/Centro de Investigaciones en Piscicultura Experimental, Facultad de Ciencias Veterinarias, Universidad Nacional de Rosario/Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina.
| | | | | | - Leandro Santos Costa
- Aquaculture Department, Federal University of Minas Gerais UFMG, Belo Horizonte, Minas Gerais, Brazil
| | - Fabricio Andrés Vigliano
- Cátedra de Histología y Embriología/Centro de Investigaciones en Piscicultura Experimental, Facultad de Ciencias Veterinarias, Universidad Nacional de Rosario/Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina
| | - Priscila Vieira Rosa
- Department of Animal Science, Federal University of Lavras UFLA, Lavras, Minas Gerais, 37200-000, Brazil
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Affiliation(s)
- Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, China.,Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Pedro A Jose
- Division of Renal Disease & Hypertension, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China
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Browning KN, Verheijden S, Boeckxstaens GE. The Vagus Nerve in Appetite Regulation, Mood, and Intestinal Inflammation. Gastroenterology 2017; 152:730-744. [PMID: 27988382 PMCID: PMC5337130 DOI: 10.1053/j.gastro.2016.10.046] [Citation(s) in RCA: 198] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 09/27/2016] [Accepted: 10/27/2016] [Indexed: 02/07/2023]
Abstract
Although the gastrointestinal tract contains intrinsic neural plexuses that allow a significant degree of independent control over gastrointestinal functions, the central nervous system provides extrinsic neural inputs that modulate, regulate, and integrate these functions. In particular, the vagus nerve provides the parasympathetic innervation to the gastrointestinal tract, coordinating the complex interactions between central and peripheral neural control mechanisms. This review discusses the physiological roles of the afferent (sensory) and motor (efferent) vagus in regulation of appetite, mood, and the immune system, as well as the pathophysiological outcomes of vagus nerve dysfunction resulting in obesity, mood disorders, and inflammation. The therapeutic potential of vagus nerve modulation to attenuate or reverse these pathophysiological outcomes and restore autonomic homeostasis is also discussed.
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Affiliation(s)
- Kirsteen N. Browning
- Department of Neural and Behavioral Science Penn State College of Medicine 500 University Drive MC H109 Hershey, PA 17033
| | - Simon Verheijden
- Translational Research Center of Gastrointestinal Disorders (TARGID) KU Leuven Herestraat 49 3000 Leuven, Belgium
| | - Guy E. Boeckxstaens
- Translational Research Center of Gastrointestinal Disorders (TARGID) KU Leuven Herestraat 49 3000 Leuven, Belgium,Division of Gastroenterology & Hepatology University Hospital Leuven Herestraat 49 3000 Leuven, Belgium,Address of correspondence: Prof. dr. Guy Boeckxstaens,
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Steinert RE, Feinle-Bisset C, Asarian L, Horowitz M, Beglinger C, Geary N. Ghrelin, CCK, GLP-1, and PYY(3-36): Secretory Controls and Physiological Roles in Eating and Glycemia in Health, Obesity, and After RYGB. Physiol Rev 2017; 97:411-463. [PMID: 28003328 PMCID: PMC6151490 DOI: 10.1152/physrev.00031.2014] [Citation(s) in RCA: 367] [Impact Index Per Article: 52.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The efficacy of Roux-en-Y gastric-bypass (RYGB) and other bariatric surgeries in the management of obesity and type 2 diabetes mellitus and novel developments in gastrointestinal (GI) endocrinology have renewed interest in the roles of GI hormones in the control of eating, meal-related glycemia, and obesity. Here we review the nutrient-sensing mechanisms that control the secretion of four of these hormones, ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), and peptide tyrosine tyrosine [PYY(3-36)], and their contributions to the controls of GI motor function, food intake, and meal-related increases in glycemia in healthy-weight and obese persons, as well as in RYGB patients. Their physiological roles as classical endocrine and as locally acting signals are discussed. Gastric emptying, the detection of specific digestive products by small intestinal enteroendocrine cells, and synergistic interactions among different GI loci all contribute to the secretion of ghrelin, CCK, GLP-1, and PYY(3-36). While CCK has been fully established as an endogenous endocrine control of eating in healthy-weight persons, the roles of all four hormones in eating in obese persons and following RYGB are uncertain. Similarly, only GLP-1 clearly contributes to the endocrine control of meal-related glycemia. It is likely that local signaling is involved in these hormones' actions, but methods to determine the physiological status of local signaling effects are lacking. Further research and fresh approaches are required to better understand ghrelin, CCK, GLP-1, and PYY(3-36) physiology; their roles in obesity and bariatric surgery; and their therapeutic potentials.
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Affiliation(s)
- Robert E Steinert
- University of Adelaide Discipline of Medicine and National Health and Medical Research Council of Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, Australia; DSM Nutritional Products, R&D Human Nutrition and Health, Basel, Switzerland; Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Department of Biomedicine and Division of Gastroenterology, University Hospital Basel, Basel, Switzerland; and Department of Psychiatry, Weill Medical College of Cornell University, New York, New York
| | - Christine Feinle-Bisset
- University of Adelaide Discipline of Medicine and National Health and Medical Research Council of Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, Australia; DSM Nutritional Products, R&D Human Nutrition and Health, Basel, Switzerland; Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Department of Biomedicine and Division of Gastroenterology, University Hospital Basel, Basel, Switzerland; and Department of Psychiatry, Weill Medical College of Cornell University, New York, New York
| | - Lori Asarian
- University of Adelaide Discipline of Medicine and National Health and Medical Research Council of Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, Australia; DSM Nutritional Products, R&D Human Nutrition and Health, Basel, Switzerland; Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Department of Biomedicine and Division of Gastroenterology, University Hospital Basel, Basel, Switzerland; and Department of Psychiatry, Weill Medical College of Cornell University, New York, New York
| | - Michael Horowitz
- University of Adelaide Discipline of Medicine and National Health and Medical Research Council of Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, Australia; DSM Nutritional Products, R&D Human Nutrition and Health, Basel, Switzerland; Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Department of Biomedicine and Division of Gastroenterology, University Hospital Basel, Basel, Switzerland; and Department of Psychiatry, Weill Medical College of Cornell University, New York, New York
| | - Christoph Beglinger
- University of Adelaide Discipline of Medicine and National Health and Medical Research Council of Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, Australia; DSM Nutritional Products, R&D Human Nutrition and Health, Basel, Switzerland; Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Department of Biomedicine and Division of Gastroenterology, University Hospital Basel, Basel, Switzerland; and Department of Psychiatry, Weill Medical College of Cornell University, New York, New York
| | - Nori Geary
- University of Adelaide Discipline of Medicine and National Health and Medical Research Council of Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, Australia; DSM Nutritional Products, R&D Human Nutrition and Health, Basel, Switzerland; Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Department of Biomedicine and Division of Gastroenterology, University Hospital Basel, Basel, Switzerland; and Department of Psychiatry, Weill Medical College of Cornell University, New York, New York
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30
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Nicola SM. Reassessing wanting and liking in the study of mesolimbic influence on food intake. Am J Physiol Regul Integr Comp Physiol 2016; 311:R811-R840. [PMID: 27534877 PMCID: PMC5130579 DOI: 10.1152/ajpregu.00234.2016] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/09/2016] [Indexed: 01/12/2023]
Abstract
Humans and animals such as rats and mice tend to overconsume calorie-dense foods, a phenomenon that likely contributes to obesity. One often-advanced explanation for why we preferentially consume sweet and fatty foods is that they are more "rewarding" than low-calorie foods. "Reward" has been subdivided into three interdependent psychological processes: hedonia (liking a food), reinforcement (formation of associations among stimuli, actions, and/or the food), and motivation (wanting the food). Research into these processes has focused on the mesolimbic system, which comprises both dopamine neurons in the ventral tegmental area and neurons in their major projection target, the nucleus accumbens. The mesolimbic system and closely connected structures are commonly referred to as the brain's "reward circuit." Implicit in this title is the assumption that "rewarding" experiences are generally the result of activity in this circuit. In this review, I argue that food intake and the preference for calorie-dense foods can be explained without reference to subjective emotions. Furthermore, the contribution of mesolimbic dopamine to food intake and preference may not be a general one of promoting or coordinating behaviors that result in the most reward or caloric intake but may instead be limited to the facilitation of a specific form of neural computation that results in conditioned approach behavior. Studies on the neural mechanisms of caloric intake regulation must address how sensory information about calorie intake affects not just the mesolimbic system but also many other forms of computation that govern other types of food-seeking and food-oriented behaviors.
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Affiliation(s)
- Saleem M Nicola
- Departments of Neuroscience and Psychiatry, Albert Einstein College of Medicine, Bronx, New York
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31
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A Review of the Evidence Supporting the Taste of Non‐esterified Fatty Acids in Humans. J AM OIL CHEM SOC 2016. [DOI: 10.1007/s11746-016-2885-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Lo SH, Cheng KC, Li YX, Chang CH, Cheng JT, Lee KS. Development of betulinic acid as an agonist of TGR5 receptor using a new in vitro assay. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:2669-76. [PMID: 27578964 PMCID: PMC5001664 DOI: 10.2147/dddt.s113197] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Background G-protein-coupled bile acid receptor 1, also known as TGR5 is known to be involved in glucose homeostasis. In animal models, treatment with a TGR5 agonist induces incretin secretion to reduce hyperglycemia. Betulinic acid, a triterpenoid present in the leaves of white birch, has been introduced as a selective TGR5 agonist. However, direct activation of TGR5 by betulinic acid has not yet been reported. Methods Transfection of TGR5 into cultured Chinese hamster ovary (CHO-K1) cells was performed to establish the presence of TGR5. Additionally, TGR5-specific small interfering RNA was employed to silence TGR5 in cells (NCI-H716 cells) that secreted incretins. Uptake of glucose by CHO-K1 cells was evaluated using a fluorescent indicator. Amounts of cyclic adenosine monophosphate and glucagon-like peptide were quantified using enzyme-linked immunosorbent assay kits. Results Betulinic acid dose-dependently increases glucose uptake by CHO-K1 cells transfected with TGR5 only, which can be considered an alternative method instead of radioligand binding assay. Additionally, signals coupled to TGR5 activation are also increased by betulinic acid in cells transfected with TGR5. In NCI-H716 cells, which endogenously express TGR5, betulinic acid induces glucagon-like peptide secretion via increasing calcium levels. However, the actions of betulinic acid were markedly reduced in NCI-H716 cells that received TGR5-silencing treatment. Therefore, the present study demonstrates the activation of TGR5 by betulinic acid for the first time. Conclusion Similar to the positive control lithocholic acid, which is the established agonist of TGR5, betulinic acid has been characterized as a useful agonist of TGR5 and can be used to activate TGR5 in the future.
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Affiliation(s)
- Shih-Hsiang Lo
- Division of Cardiology, Department of Internal Medicine, Zhongxing Branch of Taipei City Hospital; Department of History and Geography, University of Taipei, Taipei, Taiwan
| | - Kai-Chung Cheng
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Ying-Xiao Li
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan; Department of Medical Research
| | - Chin-Hong Chang
- Department of Medical Research; Department of Neurosurgery, Chi-Mei Medical Center, Yong Kang
| | - Juei-Tang Cheng
- Department of Medical Research; Institute of Medical Science, College of Health Science, Chang Jung Christian University, Tainan
| | - Kung-Shing Lee
- Department of Surgery, Pingtung Hospital; Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Chung-Ho Memorial Hospital, School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
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Pham H, Hui H, Morvaridi S, Cai J, Zhang S, Tan J, Wu V, Levin N, Knudsen B, Goddard WA, Pandol SJ, Abrol R. A bitter pill for type 2 diabetes? The activation of bitter taste receptor TAS2R38 can stimulate GLP-1 release from enteroendocrine L-cells. Biochem Biophys Res Commun 2016; 475:295-300. [PMID: 27208775 DOI: 10.1016/j.bbrc.2016.04.149] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 04/28/2016] [Indexed: 02/09/2023]
Abstract
The bitter taste receptor TAS2R38 is a G protein coupled receptor (GPCR) that has been found in many extra-oral locations like the gastrointestinal (GI) system, respiratory system, and brain, though its function at these locations is only beginning to be understood. To probe the receptor's potential metabolic role, immunohistochemistry of human ileum tissues was performed, which showed that the receptor was co-localized with glucagon-like peptide 1 (GLP-1) in L-cells. In a previous study, we had modeled the structure of this receptor for its many taste-variant haplotypes (Tan et al. 2011), including the taster haplotype PAV. The structure of this haplotype was then used in a virtual ligand screening pipeline using a collection of ∼2.5 million purchasable molecules from the ZINC database. Three compounds (Z7, Z3, Z1) were purchased from the top hits and tested along with PTU (known TAS2R38 agonist) in in vitro and in vivo assays. The dose-response study of the effect of PTU and Z7 on GLP-1 release using wild-type and TAS2R38 knockout HuTu-80 cells showed that the receptor TAS2R38 plays a major role in GLP-1 release due to these molecules. In vivo studies of PTU and the three compounds showed that they each increase GLP-1 release. PTU was also chemical linked to cellulose to slow its absorption and when tested in vivo, it showed an enhanced and prolonged GLP-1 release. These results suggest that the GI lumen location of TAS2R38 on the L-cell makes it a relatively safe drug target as systemic absorption is not needed for a TAS2R38 agonist drug to effect GLP-1 release.
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Affiliation(s)
- Hung Pham
- Departments of Biomedical Sciences and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Hongxiang Hui
- David Geffen School of Medicine, University of California, Los Angeles, CA, USA; International Center for Metabolic Diseases, Southern Medical University, Guangzhou, China
| | - Susan Morvaridi
- Departments of Biomedical Sciences and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Jiena Cai
- International Center for Metabolic Diseases, Southern Medical University, Guangzhou, China
| | - Sanqi Zhang
- Department of Medicinal Chemistry, Xi'an Jiaotong University, 710061, China
| | - Jun Tan
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA, USA; Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing, 400030, China
| | - Vincent Wu
- Veterans Affairs Greater Los Angeles Healthcare System, University of California, Los Angeles, CA, USA
| | | | - Beatrice Knudsen
- Departments of Biomedical Sciences and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - William A Goddard
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA, USA
| | - Stephen J Pandol
- Departments of Biomedical Sciences and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, University of California, Los Angeles, CA, USA; GIRx Metabolics Inc., Los Angeles, CA, USA
| | - Ravinder Abrol
- Departments of Biomedical Sciences and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA, USA; GIRx Metabolics Inc., Los Angeles, CA, USA.
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Liu J, Yu K, Zhu W. Amino acid sensing in the gut and its mediation in gut-brain signal transduction. ACTA ACUST UNITED AC 2016; 2:69-73. [PMID: 29767064 PMCID: PMC5940996 DOI: 10.1016/j.aninu.2016.03.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 03/24/2016] [Accepted: 03/25/2016] [Indexed: 11/28/2022]
Abstract
Animal gastrointestinal tract is not only a digestive organ, but also a nutrient sensing organ which detects luminal nutrient and thus can regulate food intake. There are many amino acid sensing receptors and transporters in the gut. Amino acids sensing by these receptors and transporters can stimulate the intestinal endocrine cells to release a variety of gut hormones. These hormones trigger a series of physiological effects via the nerve system. This review summarized the recent advance on the amino acid sensing receptors and transporters in the gastrointestinal tract, the gut hormones released from the intestinal endocrine cells and the hormones-induced signal transduction between the gut and brain. A better understanding of these processes may help to gain further insight into the specific role of amino acids in digestion and provide guidelines in developing strategy for the better use of amino acids in the diet.
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Affiliation(s)
- Jing Liu
- Laboratory of Gastrointestinal Microbiology, Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Kaifan Yu
- Laboratory of Gastrointestinal Microbiology, Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Weiyun Zhu
- Laboratory of Gastrointestinal Microbiology, Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
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Bolier R, Tolenaars D, Kremer AE, Saris J, Parés A, Verheij J, Bosma PJ, Beuers U, Oude Elferink RP. Enteroendocrine cells are a potential source of serum autotaxin in men. Biochim Biophys Acta Mol Basis Dis 2016; 1862:696-704. [DOI: 10.1016/j.bbadis.2016.01.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 12/22/2015] [Accepted: 01/12/2016] [Indexed: 12/26/2022]
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Cvijanovic N, Feinle-Bisset C, Young RL, Little TJ. Oral and intestinal sweet and fat tasting: impact of receptor polymorphisms and dietary modulation for metabolic disease. Nutr Rev 2015; 73:318-334. [DOI: 10.1093/nutrit/nuu026] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Fleischer J, Bumbalo R, Bautze V, Strotmann J, Breer H. Expression of odorant receptor Olfr78 in enteroendocrine cells of the colon. Cell Tissue Res 2015; 361:697-710. [DOI: 10.1007/s00441-015-2165-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/26/2015] [Indexed: 10/23/2022]
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Murray K, Placidi E, Schuring EAH, Hoad CL, Koppenol W, Arnaudov LN, Blom WAM, Pritchard SE, Stoyanov SD, Gowland PA, Spiller RC, Peters HPF, Marciani L. Aerated drinks increase gastric volume and reduce appetite as assessed by MRI: a randomized, balanced, crossover trial. Am J Clin Nutr 2015; 101:270-8. [PMID: 25646323 DOI: 10.3945/ajcn.114.096974] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Compared with nonaerated, isocaloric controls, aerated foods can reduce appetite throughout an entire dieting day. Increased gastric volumes and delayed emptying are possible but unexplored mechanisms. OBJECTIVE We tested the hypothesis that aerated drinks (foams) of differing gastric stability would increase gastric distension and reduce appetite compared with a control drink. DESIGN In a randomized, balanced, crossover trial, 18 healthy male participants consumed the following 3 skimmed-milk-based test products (all 110 kcal): 2 drinks aerated to foams by whipping (to 490 mL), one drink that was stable in the stomach [stable foam (SF)], and one drink that was less stable in the stomach [less-stable foam (LSF)], and a nonaerated drink [liquid control (LC); 140 mL]. Over 4 h, stomach contents (foam, air, and liquid) were imaged using magnetic resonance imaging (MRI), and self-reported appetite ratings were collected and quantified by the area under the curve or time to return to baseline (TTRTB). RESULTS Compared with the LC, both foams caused significantly increased gastric volumes and reduced hunger (all P < 0.001). Compared with the LSF, SF further produced a significantly slower decrease in the total gastric content (P < 0.05) and foam volume (P < 0.0001) and a longer TTRTB (197 compared with 248 min, respectively; P < 0.05), although the hunger AUC was not statistically different. Results for other appetite scales were similar. CONCLUSIONS With this MRI trial, we provide novel insights on the gastrointestinal behavior of aerated drinks by measuring separate volumes of foam, liquid, and air layers in the stomach. Appetite suppression induced by foams could largely be explained by effects on gastric volumes and emptying, which may be further enhanced by foam stability. This trial was registered at clinicaltrials.gov as NCT01690182.
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Affiliation(s)
- Kathryn Murray
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Elisa Placidi
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Ewoud A H Schuring
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Caroline L Hoad
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Wieneke Koppenol
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Luben N Arnaudov
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Wendy A M Blom
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Susan E Pritchard
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Simeon D Stoyanov
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Penny A Gowland
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Robin C Spiller
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Harry P F Peters
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
| | - Luca Marciani
- From the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy (KM, EP, CLH, SEP, and PAG), and the Nottingham Digestive Diseases Centre, School of Medicine, and Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals (RCS and LM), University of Nottingham, Nottingham United Kingdom, and Unilever Research and Development, Vlaardingen, The Netherlands (EAHS, WK, LNA, WAMB, SDS, and HPFP)
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Little TJ, Isaacs NJ, Young RL, Ott R, Nguyen NQ, Rayner CK, Horowitz M, Feinle-Bisset C. Characterization of duodenal expression and localization of fatty acid-sensing receptors in humans: relationships with body mass index. Am J Physiol Gastrointest Liver Physiol 2014; 307:G958-67. [PMID: 25258406 DOI: 10.1152/ajpgi.00134.2014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fatty acids (FAs) stimulate the secretion of gastrointestinal hormones, including cholecystokinin (CCK) and glucagon like peptide-1 (GLP-1), which suppress energy intake. In obesity, gastrointestinal responses to FAs are attenuated. Recent studies have identified a key role for the FA-sensing receptors cluster of differentiation (CD)36, G protein-coupled receptor (GPR)40, GPR120, and GPR119 in mediating gastrointestinal hormone secretion. This study aimed to determine the expression and localization of these receptors in the duodenum of humans and to examine relationships with obesity. Duodenal mucosal biopsies were collected from nine lean [body mass index (BMI): 22 ± 1 kg/m2], six overweight (BMI: 28 ± 1 kg/m2), and seven obese (BMI: 49 ± 5 kg/m2) participants. Absolute levels of receptor transcripts were quantified using RT-PCR, while immunohistochemistry was used for localization. Transcripts were expressed in the duodenum of lean, overweight, and obese individuals with abundance of CD36>>GPR40>GPR120>GPR119. Expression levels of GPR120 (r = 0.46, P = 0.03) and CD36 (r = 0.69, P = 0.0004) were directly correlated with BMI. There was an inverse correlation between expression of GPR119 with BMI (r2 = 0.26, P = 0.016). Immunolabeling studies localized CD36 to the brush border membrane of the duodenal mucosa and GPR40, GPR120, and GPR119 to enteroendocrine cells. The number of cells immunolabeled with CCK (r = -0.54, P = 0.03) and GLP-1 (r = -0.49, P = 0.045) was inversely correlated with BMI, such that duodenal CCK and GLP-1 cell density decreased with increasing BMI. In conclusion, CD36, GPR40, GPR120, and GPR119 are expressed in the human duodenum. Transcript levels of duodenal FA receptors and enteroendocrine cell density are altered with increasing BMI, suggesting that these changes may underlie decreased gastrointestinal hormone responses to fat and impaired energy intake regulation in obesity.
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Affiliation(s)
- Tanya J Little
- University of Adelaide Discipline of Medicine, Adelaide, South Australia, Australia; National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, South Australia, Australia; and
| | - Nicole J Isaacs
- University of Adelaide Discipline of Medicine, Adelaide, South Australia, Australia
| | - Richard L Young
- University of Adelaide Discipline of Medicine, Adelaide, South Australia, Australia; National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, South Australia, Australia; and
| | - Raffael Ott
- University of Adelaide Discipline of Medicine, Adelaide, South Australia, Australia
| | - Nam Q Nguyen
- National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, South Australia, Australia; and Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Christopher K Rayner
- University of Adelaide Discipline of Medicine, Adelaide, South Australia, Australia; National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, South Australia, Australia; and Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Michael Horowitz
- University of Adelaide Discipline of Medicine, Adelaide, South Australia, Australia; National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, South Australia, Australia; and
| | - Christine Feinle-Bisset
- University of Adelaide Discipline of Medicine, Adelaide, South Australia, Australia; National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, South Australia, Australia; and
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Additive effects of gastric volumes and macronutrient composition on the sensation of postprandial fullness in humans. Eur J Clin Nutr 2014; 69:380-4. [PMID: 25226819 PMCID: PMC4351404 DOI: 10.1038/ejcn.2014.194] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 08/06/2014] [Accepted: 08/11/2014] [Indexed: 02/07/2023]
Abstract
Background/Objectives: Intake of food or fluid distends the stomach and triggers mechanoreceptors and vagal afferents. Wall stretch and tension produces a feeling of fullness. Duodenal infusion studies assessing gastric sensitivity by barostat have shown that the products of fat digestion have a greater effect on the sensation of fullness and also dyspeptic symptoms than carbohydrates. We tested here the hypothesis that fat and carbohydrate have different effects on gastric sensation under physiological conditions using non-invasive magnetic resonance imaging (MRI) to measure gastric volumes. Subjects/Methods: Thirteen healthy subjects received a rice pudding test meal with added fat or added carbohydrate on two separate occasions and underwent serial postprandial MRI scans for 4.5 h. Fullness was assessed on a 100-mm visual analogue scale. Results: Gastric half emptying time was significantly slower for the high-carbohydrate meal than for the high-fat meal, P=0.0327. Fullness significantly correlated with gastric volumes for both meals; however, the change from baseline in fullness scores was higher for the high-fat meal for any given change in stomach volume (P=0.0147), despite the lower energy content and faster gastric emptying of the high-fat meal. Conclusions: Total gastric volume correlates positively and linearly with postprandial fullness and ingestion of a high-fat meal increases this sensation compared with high-carbohydrate meal. These findings can be of clinical interest in patients presenting with postprandial dyspepsia whereby manipulating gastric sensitivity by dietary intervention may help to control digestive sensations.
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Ullmer C, Alvarez Sanchez R, Sprecher U, Raab S, Mattei P, Dehmlow H, Sewing S, Iglesias A, Beauchamp J, Conde-Knape K. Systemic bile acid sensing by G protein-coupled bile acid receptor 1 (GPBAR1) promotes PYY and GLP-1 release. Br J Pharmacol 2014; 169:671-84. [PMID: 23488746 DOI: 10.1111/bph.12158] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 01/18/2013] [Accepted: 02/07/2013] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Nutrient sensing in the gut is believed to be accomplished through activation of GPCRs expressed on enteroendocrine cells. In particular, L-cells located predominantly in distal regions of the gut secrete glucagon-like peptide 1 (GLP-1) and peptide tyrosine-tyrosine (PYY) upon stimulation by nutrients and bile acids (BA). The study was designed to address the mechanism of hormone secretion in L-cells stimulated by the BA receptor G protein-coupled bile acid receptor 1 (GPBAR1). EXPERIMENTAL APPROACH A novel, selective, orally bioavailable, and potent GPBAR1 agonist, RO5527239, was synthesized in order to investigate L-cell secretion in vitro and in vivo in mice and monkey. In analogy to BA, RO5527239 was conjugated with taurine to reduce p.o. bioavailability yet retaining its potency. Using RO5527239 and tauro-RO5527239, the acute secretion effects on L-cells were addressed via different routes of administration. KEY RESULTS GPBAR1 signalling triggers the co-secretion of PYY and GLP-1, and leads to improved glucose tolerance. The strong correlation of plasma drug exposure and plasma PYY levels suggests activation of GPBAR1 from systemically accessible compartments. In contrast to the orally bioavailable agonist RO5527239, we show that tauro-RO5527239 triggers PYY release only when applied intravenously. Compared to mice, a slower and more sustained PYY secretion was observed in monkeys. CONCLUSION AND IMPLICATIONS Selective GPBAR1 activation elicits a strong secretagogue effect on L-cells, which primarily requires systemic exposure. We suggest that GPBAR1 is a key player in the intestinal proximal-distal loop that mediates the early phase of nutrient-evoked L-cell secretion effects.
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Affiliation(s)
- C Ullmer
- DTA CV & Metabolic Diseases, DTA CV and Metabolic Diseases, Pharma Research and Early Development, F. Hoffmann-La Roche AG, Basel, Switzerland.
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El-Salhy M, Gilja OH, Hatlebakk JG, Hausken T. Stomach antral endocrine cells in patients with irritable bowel syndrome. Int J Mol Med 2014; 34:967-74. [PMID: 25110039 PMCID: PMC4152137 DOI: 10.3892/ijmm.2014.1887] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 07/23/2014] [Indexed: 12/11/2022] Open
Abstract
To the best of our knowledge, stomach antral endocrine cells have not previously been investigated in patients with irritable bowel syndrome (IBS). Thus, in the present study, 76 patients with IBS were examined (designated as IBS-total). Diarrhoea was the predominant symptom in 26 of these patients (IBS-D), while in 21 patients, the predominant symptoms were both diarrhoea and constipation (IBS-M) and in 29 patients the predominant symptom was constipation (IBS-C). Forty-three healthy subjects were enrolled as the controls. Stomach antral biopsy samples obtained from all of the subjects were immunostained using the avidin-biotin-complex method for serotonin, gastrin, somatostatin and serotonin transporter (SERT). The immunopositive cell densities and immunoreactivity intensities were determined by computer-aided image analysis. The density of the serotonin-immunoreactive cells was significantly decreased in the IBS-M patients and increased in the IBS-C patients relative to the controls. The immunoreactivity intensity did not differ significantly between the controls and IBS-total. The density of the gastrin-immunoreactive cells was significantly greater in the IBS-D, IBS-M and IBS-C patients than in the controls. The immunoreactivity intensity of gastrin was significantly greater in the IBS-D patients than in the controls. The density of the somatostatin-immunoreactive cells cells was significantly lower in the IBS-total, IBS-D, IBS-M and IBS-C patients than in the controls. The immunoreactivity intensities of both somatostatin and SERT did not differ significantly between the controls and IBS-total. The increase in gastrin cell density and the decrease in somatostatin cell density in all IBS subtypes may cause high levels of gastric secretion, which may in turn contribute to the high incidence of dyspepsia and gastro-oesophageal reflux observed in patients with IBS.
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Affiliation(s)
- Magdy El-Salhy
- Division of Gastroenterology, Department of Medicine, Stord Helse-Fonna Hospital, Stord, Norway
| | - Odd Helge Gilja
- Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Jan Gunnar Hatlebakk
- Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Trygve Hausken
- Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway
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Glucagon-like peptide 1 and peptide YY are in separate storage organelles in enteroendocrine cells. Cell Tissue Res 2014; 357:63-9. [DOI: 10.1007/s00441-014-1886-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 03/27/2014] [Indexed: 12/17/2022]
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Hansen HS. Role of anorectic N-acylethanolamines in intestinal physiology and satiety control with respect to dietary fat. Pharmacol Res 2014; 86:18-25. [PMID: 24681513 DOI: 10.1016/j.phrs.2014.03.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 03/17/2014] [Accepted: 03/18/2014] [Indexed: 02/06/2023]
Abstract
Anandamide is a well-known agonist for the cannabinoid receptors. Along with endogenous anandamide other non-endocannabinoid N-acylethanolamines are also formed, apparently in higher amounts. These include mainly oleoylethanolamide (OEA), palmitoyelethanolamide (PEA) and linoleoylethanolamide (LEA), and they have biological activity by themselves being anorectic and anti-inflammatory. It appears that the major effect of dietary fat on the level of these molecules is in the gastrointestinal system, where OEA, PEA and LEA in the enterocytes may function as homeostatic signals, which are decreased by prolonged consumption of a high-fat diet. These lipid amides appear to mediate their signaling activity via activation of PPARα in the enterocyte followed by activation of afferent vagal fibers leading to the brain. Through this mechanism OEA, PEA and LEA may both reduce the consumption of a meal as well as increase the reward value of the food. Thus, they may function as homeostatic intestinal signals involving hedonic aspects that contribute to the regulation of the amounts of dietary fat to be ingested.
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Affiliation(s)
- Harald S Hansen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark.
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Kim K, Park M, Lee YM, Rhyu MR, Kim HY. Ginsenoside metabolite compound K stimulates glucagon-like peptide-1 secretion in NCI-H716 cells via bile acid receptor activation. Arch Pharm Res 2014; 37:1193-200. [PMID: 24590628 DOI: 10.1007/s12272-014-0362-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 02/19/2014] [Indexed: 12/13/2022]
Abstract
Compound K (CK) is a major metabolite of ginsenosides that is absorbed. CK has antidiabetic effects, although the mechanisms underlying the effects of CK have not fully been known. To elucidate the mechanisms underlying the antidiabetic effects of CK, we studied the effects of CK on GLP-1 secretion from NCI-H716 cells, and explored the mechanisms underlying CK-induced GLP-1 secretion. Treatment of NCI-H716 cells with 10, 50, and 100 μM CK significantly increased GLP-1 secretion, and intracellular Ca²⁺ and cAMP levels in a dose-dependent manner. Transfection of NCI-H716 cells with siRNA specific to α-gustducin and siRNA specific to TAS1R3 had no effect on CK-induced GLP-1 secretion and Ca²⁺ increase. However, transfection of NCI-H716 cells with TGR5-specific siRNA significantly inhibited CK-induced GLP-1 secretion and the increase in Ca²⁺ and cAMP levels. Moreover, CK showed human TGR5 agonist activity in CHO-K1 cells transiently transfected with human TGR5. Our data provide a novel mechanism of CK for antidiabetic effects. Moreover, the findings might suggest that CK is a potential agent that has multiple biological functions in the body via GLP-1 secretion and TGR5 activation.
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Affiliation(s)
- Kyong Kim
- Division of Metabolism and Functionality Research, Korea Food Research Institute, 62 Road-1201, Anyang-Pangyo-ro, Bundang-gu, Sungnam-si, Kyonggi-do, 463-746, Korea
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47
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Dockray GJ. Enteroendocrine cell signalling via the vagus nerve. Curr Opin Pharmacol 2013; 13:954-8. [DOI: 10.1016/j.coph.2013.09.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 08/28/2013] [Accepted: 09/04/2013] [Indexed: 02/06/2023]
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ANGPTL4 is produced by entero-endocrine cells in the human intestinal tract. Histochem Cell Biol 2013; 141:383-91. [DOI: 10.1007/s00418-013-1157-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2013] [Indexed: 12/24/2022]
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van der Klaauw AA, Keogh JM, Henning E, Trowse VM, Dhillo WS, Ghatei MA, Farooqi IS. High protein intake stimulates postprandial GLP1 and PYY release. Obesity (Silver Spring) 2013; 21:1602-7. [PMID: 23666746 PMCID: PMC6548554 DOI: 10.1002/oby.20154] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 10/24/2012] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Meals high in protein induce greater intermeal satiety than meals high in fat and carbohydrates. We studied the gut hormone response and subsequent food intake after breakfasts high in protein, carbohydrate or high in fat controlled for volume, calories and appearance. DESIGN AND METHODS Eight healthy volunteers participated in this randomized three-way crossover study. Study breakfasts were calculated to provide 20% of daily energy requirements and provided either 60% of energy from protein, fat or carbohydrate. Blood was drawn half-hourly for 4 h; energy intake at a subsequent ad libitum meal was measured. RESULTS Total ghrelin decreased after food intake equally with the three breakfasts. PYY levels were highest after the high protein breakfast (P = 0.005). Indeed, PYY at 240 min was highest after the high protein breakfast compared to the high fat breakfast and to the high carbohydrate breakfast (P = 0.011 and P = 0.012, respectively). GLP-1 levels were highest after the high protein breakfast (P = 0.041) at 120 min and remained higher throughout the study. These differences in gut hormones did not translate into differences in food intake (1023 ± 390 kcal after high protein, 1016 ± 388 kcal after high fat and 1158 ± 433 kcal after high carbohydrate). CONCLUSION We conclude that a high protein meal increases circulating concentrations of the gut hormones PYY and GLP-1, but when meals are matched for volume, appearance and caloric value, these gut hormone changes do not translate into a reduction in ad libitum food intake.
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Affiliation(s)
- Agatha A van der Klaauw
- Department of Clinical Biochemistry, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
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Abstract
Visceral sensory neurons activate reflex pathways that control gut function and also give rise to important sensations, such as fullness, bloating, nausea, discomfort, urgency and pain. Sensory neurons are organised into three distinct anatomical pathways to the central nervous system (vagal, thoracolumbar and lumbosacral). Although remarkable progress has been made in characterizing the roles of many ion channels, receptors and second messengers in visceral sensory neurons, the basic aim of understanding how many classes there are, and how they differ, has proven difficult to achieve. We suggest that just five structurally distinct types of sensory endings are present in the gut wall that account for essentially all of the primary afferent neurons in the three pathways. Each of these five major structural types of endings seems to show distinctive combinations of physiological responses. These types are: 'intraganglionic laminar' endings in myenteric ganglia; 'mucosal' endings located in the subepithelial layer; 'muscular-mucosal' afferents, with mechanosensitive endings close to the muscularis mucosae; 'intramuscular' endings, with endings within the smooth muscle layers; and 'vascular' afferents, with sensitive endings primarily on blood vessels. 'Silent' afferents might be a subset of inexcitable 'vascular' afferents, which can be switched on by inflammatory mediators. Extrinsic sensory neurons comprise an attractive focus for targeted therapeutic intervention in a range of gastrointestinal disorders.
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