1
|
Sun S, Wang A, Kou R, Xue H, Zhao X, Yang B, Shi M, Wang Y, Yan Q, Qu M, Wang Y, Gao Z. Duodenal-Jejunal Bypass Restores Sweet Taste Receptor-Mediated Glucose Sensing and Absorption in Diabetic Rats. J Diabetes Res 2024; 2024:5544296. [PMID: 39263491 PMCID: PMC11390237 DOI: 10.1155/2024/5544296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 01/04/2024] [Accepted: 08/07/2024] [Indexed: 09/13/2024] Open
Abstract
Aim: The aim of the study is to identify the regulatory role of intestinal sweet taste receptors (STRs) and glucose transporters (SGLT1, GLUT2) and gut peptide secretion in duodenal-jejunal bypass (DJB)-ameliorated glycemic control in Type 2 diabetes. Materials and Methods: DJB and sham surgeries were performed in streptozotocin-induced diabetic male rats. The blood GLP-1 and GLP-2 levels were evaluated under feeding and fasting conditions. The expression of STRs (T1R2, T1R3), sweet taste signaling effector (Gα-gustducin), SGLT1, and GLUT2 was detected in the intestinal alimentary limb (A limb), biliopancreatic limb (BP limb), and common limb (C limb). The effects of STR inhibition on glucose control were measured with lactisole. Results: Glucose tolerance was improved in DJB-operated rats compared with the sham group, similar to that of normal control rats, without significant differences in food intake and body weight. The plasma GLP-1 levels of DJB rats were increased under diet-fed condition, and GLP-2 levels were increased after fasting. The villus height and crypt depth were significantly increased in the A limb of DJB-operated rats. In addition, GLP-1 expression was restored in enterocytes. The expression of T1R2, Gα-gustducin, and SGLT1 was elevated in the A limb after DJB, while GLUT2 was downregulated in the A, BP, and C limbs. The localization of GLUT2 was normalized in the three intestinal limbs after DJB. However, the beneficial effects of DJB on glucose control were abolished in the presence of lactisole in vivo. Conclusion: DJB ameliorates glycemic control probably by restoring STR-mediated glucose sensing and absorption with the responses of GLP-1 and GLP-2 to carbohydrate.
Collapse
Affiliation(s)
- Sipeng Sun
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Anping Wang
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Rongguan Kou
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Hantao Xue
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Xiangyu Zhao
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Ben Yang
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Mengqi Shi
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Yubing Wang
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Qingtao Yan
- Department of Pediatric Surgery Weifang People's Hospital The First Affiliated Hospital of Shandong Second Medical University, Weifang 261021, China
| | - Meihua Qu
- Translational Medical Center Weifang Second People's Hospital, Weifang 261021, China
| | - Yi Wang
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| | - Zhiqin Gao
- School of Life Science and Technology Shandong Second Medical University, Weifang 261021, China
| |
Collapse
|
2
|
Neurohormonal Changes in the Gut–Brain Axis and Underlying Neuroendocrine Mechanisms following Bariatric Surgery. Int J Mol Sci 2022; 23:ijms23063339. [PMID: 35328759 PMCID: PMC8954280 DOI: 10.3390/ijms23063339] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/15/2022] [Accepted: 03/16/2022] [Indexed: 02/05/2023] Open
Abstract
Obesity is a complex, multifactorial disease that is a major public health issue worldwide. Currently approved anti-obesity medications and lifestyle interventions lack the efficacy and durability needed to combat obesity, especially in individuals with more severe forms or coexisting metabolic disorders, such as poorly controlled type 2 diabetes. Bariatric surgery is considered an effective therapeutic modality with sustained weight loss and metabolic benefits. Numerous genetic and environmental factors have been associated with the pathogenesis of obesity, while cumulative evidence has highlighted the gut–brain axis as a complex bidirectional communication axis that plays a crucial role in energy homeostasis. This has led to increased research on the roles of neuroendocrine signaling pathways and various gastrointestinal peptides as key mediators of the beneficial effects following weight-loss surgery. The accumulate evidence suggests that the development of gut-peptide-based agents can mimic the effects of bariatric surgery and thus is a highly promising treatment strategy that could be explored in future research. This article aims to elucidate the potential underlying neuroendocrine mechanisms of the gut–brain axis and comprehensively review the observed changes of gut hormones associated with bariatric surgery. Moreover, the emerging role of post-bariatric gut microbiota modulation is briefly discussed.
Collapse
|
3
|
Zhang Z, Li H, Su Y, Ma J, Yuan Y, Yu Z, Shi M, Shao S, Zhang Z, Hölscher C. Neuroprotective Effects of a Cholecystokinin Analogue in the 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine Parkinson’s Disease Mouse Model. Front Neurosci 2022; 16:814430. [PMID: 35368248 PMCID: PMC8964967 DOI: 10.3389/fnins.2022.814430] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 02/11/2022] [Indexed: 01/13/2023] Open
Abstract
Parkinson’s disease (PD) is a chronic neurodegenerative disease. Type 2 diabetes mellitus (T2DM) has been identified as a risk factor for PD. Drugs originally developed for T2DM treatment such as liraglutide have shown neuroprotective effects in mouse models of PD. Cholecystokinin (CCK) is a peptide hormone with growth factor properties. Here, we demonstrate the neuroprotective effects of the (pGLu)-(Gln)-CCK8 analogue in an acute PD mouse model induced by 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Administration of CCK analogue (50 nmol/kg ip.) for 14 days treatment improved the locomotor and exploratory activity of mice, and improved bradykinesia and movement balance of mice. The CCK analogue administration also restored tyrosine hydroxylase (TH) positive dopaminergic neurons number and synapse number (synaptophysin levels) in the substantia nigra pars compacta (SNpc). The CCK analogue decreased glia activation and neuroinflammation in the SNpc, and regulated autophagy dysfunction induced by MPTP. CCK analogue protected against mitochondrial damage and ER stress, and also decreased the ratio of apoptosis signaling molecules Bax/Bcl-2. Importantly, the CCK analogue improved the decrease of p-CREBS133 growth factor signaling in the SNpc. Therefore, the CCK analogue promotes cell survival of dopaminergic neuron in the SNpc by activating the cAMP/PKA/CREB pathway that also inhibits apoptosis and regulates autophagy impairment. The present results indicate that CCK analogue shows a promising potential for the treatment of PD.
Collapse
Affiliation(s)
- Zijuan Zhang
- Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
- School of Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Hai Li
- Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
- School of Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Yunfang Su
- Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Jinlian Ma
- Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Ye Yuan
- Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Ziyang Yu
- School of Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Ming Shi
- School of Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Simai Shao
- School of Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
| | - Zhenqiang Zhang
- Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
- Zhenqiang Zhang,
| | - Christian Hölscher
- Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China
- Neurology Department of the Second Associated Hospital of Shanxi Medical University, Taiyuan, China
- *Correspondence: Christian Hölscher,
| |
Collapse
|
4
|
Koliaki C, Liatis S, Dalamaga M, Kokkinos A. The Implication of Gut Hormones in the Regulation of Energy Homeostasis and Their Role in the Pathophysiology of Obesity. Curr Obes Rep 2020; 9:255-271. [PMID: 32647952 DOI: 10.1007/s13679-020-00396-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW This review provides an update on the role of gut hormones and their interactions in the regulation of energy homeostasis, describes gut hormone adaptations in obesity and in response to weight loss, and summarizes the current evidence on the role of gut hormone-based therapies for obesity treatment. RECENT FINDINGS Gut hormones play a key role in regulating eating behaviour, energy and glucose homeostasis. Dysregulated gut hormone responses have been proposed to be pathogenetically involved in the development and perpetuation of obesity. Summarizing the major gut hormone changes in obesity, obese individuals are characterized by blunted postprandial ghrelin suppression, loss of premeal ghrelin peaks, impaired diurnal ghrelin variability and reduced fasting and postprandial levels of anorexigenic peptides. Adaptive alterations of gut hormone levels are implicated in weight regain, thus complicating hypocaloric dietary interventions, and can further explain the profound weight loss and metabolic improvement following bariatric surgery. A plethora of compounds mimicking gut hormone changes after bariatric surgery are currently under investigation, introducing a new era in the pharmacotherapy of obesity. The current trend is to combine different gut hormone receptor agonists and target multiple systems simultaneously, in order to replicate as closely as possible the gut hormone milieu after bariatric surgery and circumvent the counter-regulatory adaptive changes associated with dietary energy restriction. An increasing number of preclinical and early-phase clinical trials reveal the additive benefits obtained with dual or triple gut peptide receptor agonists in reducing body weight and improving glycaemia. Gut hormones act as potent regulators of energy and glucose homeostasis. Therapeutic strategies targeting their levels or receptors emerge as a promising approach to treat patients with obesity and hyperglycaemia.
Collapse
Affiliation(s)
- Chrysi Koliaki
- First Department of Propaedeutic Internal Medicine, Medical School, Laiko General Hospital, National Kapodistrian University of Athens, 17 Agiou Thoma Street, 11527, Athens, Greece.
| | - Stavros Liatis
- First Department of Propaedeutic Internal Medicine, Medical School, Laiko General Hospital, National Kapodistrian University of Athens, 17 Agiou Thoma Street, 11527, Athens, Greece
| | - Maria Dalamaga
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Alexander Kokkinos
- First Department of Propaedeutic Internal Medicine, Medical School, Laiko General Hospital, National Kapodistrian University of Athens, 17 Agiou Thoma Street, 11527, Athens, Greece
| |
Collapse
|
5
|
Kokkinos A, Tsilingiris D, le Roux CW, Rubino F, Mantzoros CS. Will medications that mimic gut hormones or target their receptors eventually replace bariatric surgery? Metabolism 2019; 100:153960. [PMID: 31412266 DOI: 10.1016/j.metabol.2019.153960] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/31/2019] [Accepted: 08/05/2019] [Indexed: 02/07/2023]
Abstract
Bariatric surgery is currently the most effective therapeutic modality through which sustained beneficial effects on weight loss and metabolic improvement are achieved. During recent years, indications for bariatric surgery have been expanded to include cases of poorly controlled type 2 (T2DM) diabetes mellitus in lesser extremes of body weight. A spectrum of the beneficial effects of surgery is attributed to robust changes of postprandial gut peptide responses that are observed post operatively. Consolidated knowledge regarding gut peptide physiology as well as emerging new evidence shedding light on the mode of action of previously overlooked gut hormones provide appealing potential obesity and T2DM therapeutic perspectives. The accumulation of evidence from the effect of exogenous administration of native gut peptides alone or in combinations to humans as well as the development of mimetic agents exerting agonistic effects on combinations of gut hormone receptors pave the way for future integrated gut peptide-based treatments, which may mimic the effects of bariatric surgery.
Collapse
Affiliation(s)
- Alexander Kokkinos
- First Department of Propaedeutic Internal Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece.
| | - Dimitrios Tsilingiris
- First Department of Propaedeutic Internal Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
| | - Carel W le Roux
- Diabetes Complications Research Centre, University College Dublin, Dublin, Ireland
| | - Francesco Rubino
- Department of Metabolic and Bariatric Surgery, Diabetes and Nutritional Science Division, King's College Hospital, London, United Kingdom
| | - Christos S Mantzoros
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, USA
| |
Collapse
|
6
|
Abstract
PURPOSE OF REVIEW In recent years, the role of the gastrointestinal (GI) tract in energy homeostasis through modulation of the digestion and absorption of carbohydrates and the production of incretin hormones is well recognized. RECENT FINDINGS Bariatric surgery for obesity has been a very effective method in substantially improving weight, and numerous studies have focused on intestinal adaptation after bariatric procedures. A number of structural and functional changes in the GI tract have been reported postsurgery, which could be responsible for the altered hormonal responses. Furthermore, the change in food absorption rate and the intestinal regions exposed to carbohydrates may affect blood glucose response. This review hopes to give new insights into the direct role of gut hormones, by summarising the metabolic effects of bariatric surgery.
Collapse
Affiliation(s)
- Georgios K Dimitriadis
- Division of Translational and Experimental Medicine, Clinical Sciences Research Laboratories, University of Warwick Medical School, Coventry, CV2 2DX, UK.
- Academic Division of Diabetes, Endocrinology and Metabolism, Imperial College London, Hammersmith Campus, London, W12 0NN, UK.
- Division of Translational and Experimental Medicine-Metabolic and Vascular Health, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK.
| | - Manpal S Randeva
- Division of Translational and Experimental Medicine, Clinical Sciences Research Laboratories, University of Warwick Medical School, Coventry, CV2 2DX, UK
| | - Alexander D Miras
- Academic Division of Diabetes, Endocrinology and Metabolism, Imperial College London, Hammersmith Campus, London, W12 0NN, UK
| |
Collapse
|
7
|
Evers SS, Sandoval DA, Seeley RJ. The Physiology and Molecular Underpinnings of the Effects of Bariatric Surgery on Obesity and Diabetes. Annu Rev Physiol 2017; 79:313-334. [DOI: 10.1146/annurev-physiol-022516-034423] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Simon S. Evers
- Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109;
| | - Darleen A. Sandoval
- Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109;
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109
| | - Randy J. Seeley
- Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109;
- Department of Nutritional Sciences, University of Michigan, Ann Arbor, Michigan 48109
| |
Collapse
|
8
|
Meek CL, Lewis HB, Reimann F, Gribble FM, Park AJ. The effect of bariatric surgery on gastrointestinal and pancreatic peptide hormones. Peptides 2016; 77:28-37. [PMID: 26344355 DOI: 10.1016/j.peptides.2015.08.013] [Citation(s) in RCA: 179] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 08/18/2015] [Accepted: 08/19/2015] [Indexed: 12/17/2022]
Abstract
Bariatric surgery for obesity has proved to be an extremely effective method of promoting long-term weight reduction with additional beneficial metabolic effects, such as improved glucose tolerance and remission of type 2 diabetes. A range of bariatric procedures are in common use, including gastric banding, sleeve gastrectomy and the Roux-en-Y gastric bypass. Although the mechanisms underlying the efficacy of bariatric surgery are unclear, gastrointestinal and pancreatic peptides are thought to play an important role. The aim of this review is to summarise the effects of different bariatric surgery procedures upon gastrointestinal and pancreatic peptides, including ghrelin, gastrin, cholecystokinin (CCK), glucose-dependent insulinotropic hormone (GIP), glucagon-like peptide 1 (GLP-1), peptide YY (PYY), oxyntomodulin, insulin, glucagon and somatostatin.
Collapse
Affiliation(s)
- Claire L Meek
- Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrookes's Hospital, Box 289, Hills Road, Cambridge CB2 0QQ, United Kingdom; Department of Clinical Biochemistry, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Hannah B Lewis
- Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrookes's Hospital, Box 289, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Frank Reimann
- Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrookes's Hospital, Box 289, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Fiona M Gribble
- Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrookes's Hospital, Box 289, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Adrian J Park
- Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrookes's Hospital, Box 289, Hills Road, Cambridge CB2 0QQ, United Kingdom; Department of Clinical Biochemistry, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, United Kingdom
| |
Collapse
|
9
|
Duodenojejunal Bypass Leads to Altered Gut Microbiota and Strengthened Epithelial Barriers in Rats. Obes Surg 2015; 26:1576-83. [DOI: 10.1007/s11695-015-1968-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
10
|
Abstract
BACKGROUND Bariatric surgical procedures are classified by their presumed mechanisms of action: restrictive, malabsorptive or a combination of both. However, this dogma is questionable and remains unproven. We investigated post-operative changes in nutrient absorption and transit time following bariatric surgery. METHODS Participants were recruited into four groups: obese controls (body mass index (BMI) >30 kg/m2, n = 7), adjustable gastric banding (n = 6), Roux-en-Y gastric bypass (RYGB, n = 7) and biliopancreatic diversion with duodenal switch (DS, n = 5). Participants underwent sulphasalazine/sulphapyridine tests (oro-caecal transit time); fasting plasma citrulline (functional enterocyte mass); 3 days faecal collection for faecal elastase 1 (FE-1); calprotectin (FCp); faecal fatty acids (pancreatic exocrine function, gut inflammation and fat excretion, respectively); and 5 h D-xylose, L-rhamnose and lactulose test (intestinal absorption and permeability). RESULTS Age and gender were not different but BMI differed between groups (p = 0.001). No difference in oro-caecal transit time (p = 0.935) or functional enterocyte mass (p = 0.819) was detected. FCp was elevated post-RYGB vs. obese (p = 0.016) and FE-1 was reduced post-RYGB vs. obese (p = 0.002). Faecal fat concentrations were increased post-DS vs. obese (p = 0.038) and RYGB (p = 0.024) and were also higher post-RYGB vs. obese (p = 0.033). Urinary excretion of D-xylose and L-rhamnose was not different between the groups; however, lactulose/rhamnose ratio was elevated post-DS vs. other groups (all p < 0.02), suggesting increased intestinal permeability. CONCLUSIONS Following RYGB, there are surprisingly few abnormalities or indications of severe malabsorption of fats or sugars. Small bowel adaptation after bariatric surgery may be key to understanding the mechanisms responsible for the beneficial metabolic effects of these operations.
Collapse
|
11
|
Rotondo A, Amato A, Baldassano S, Lentini L, Mulè F. Gastric relaxation induced by glucagon-like peptide-2 in mice fed a high-fat diet or fasted. Peptides 2011; 32:1587-92. [PMID: 21771622 DOI: 10.1016/j.peptides.2011.06.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 06/29/2011] [Accepted: 06/29/2011] [Indexed: 12/17/2022]
Abstract
Glucagon-like peptide-2 (GLP-2) is a nutrient-responsive gut hormone that increases the intestinal absorption. Exogenous GLP-2 also induces gastric fundus relaxation with possible implications for emptying rate or feeling of satiety. GLP-2 actions are mediated by GLP-2 receptor (GLP-2R), located on enteric neurons and myofibroblasts in murine gastrointestinal tract. Because it is not known whether changes in the endogenous GLP-2R levels occur in different nutritional states, we examined the GLP-2R gene and protein expression in gastric fundus from standard diet (STD)-fed, 12-h and 24-h fasted and re-fed, or high-fat diet (HFD)-fed mice and we analyzed the mechanical responses to exogenous GLP-2 in the stomach from different groups of animals. GLP-2 expression was examined using real-time reverse-transcription polymerase chain reaction and western blotting. The gastric mechanical activity from whole-organ was recorded in vitro as changes of intraluminal pressure. GLP-2R expression in fundic region from 12-h or 24-h fasted mice was reduced in comparison with STD-fed animals and returned to control values in re-fed mice, while it was increased in HFD-fed mice. The exogenous GLP-2 efficacy in inducing gastric relaxation, normalized to isoproterenol response, was decreased in stomach from fasted mice and it was increased in stomach from HFD-fed mice in comparison with STD-fed mice. In conclusion, the nutritional state influences GLP-2R expression in murine gastric preparations. The changes in the GLP-2R expression are associated with modifications of GLP-2 gastric relaxant efficacy. This could represent an adaptive response to reduced or increased nutrient intake.
Collapse
Affiliation(s)
- Alessandra Rotondo
- Dipartimento di Scienze e Tecnologie Molecolari e Biomolecolari (STEMBIO), Università di Palermo, 90128 Palermo, Italy
| | | | | | | | | |
Collapse
|
12
|
Connor E, Baldwin R, Capuco A, Evock-Clover C, Ellis S, Sciabica K. Characterization of glucagon-like peptide 2 pathway member expression in bovine gastrointestinal tract. J Dairy Sci 2010; 93:5167-78. [DOI: 10.3168/jds.2010-3205] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 07/08/2010] [Indexed: 12/22/2022]
|
13
|
Gut hypertrophy after gastric bypass is associated with increased glucagon-like peptide 2 and intestinal crypt cell proliferation. Ann Surg 2010; 252:50-6. [PMID: 20562614 DOI: 10.1097/sla.0b013e3181d3d21f] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE We aimed to determine changes in crypt cell proliferation and glucagon-like peptide-2 (GLP-2) in rodents and man after Roux-en-Y gastric bypass (RYGB). SUMMARY OF BACKGROUND DATA Roux-en-Y gastric bypass results in sustained weight loss and reduced appetite with only mild gastrointestinal side effects. Glucagon-like peptide-2 released from intestinal l-cells after nutrient intake stimulates intestinal crypt cell proliferation and mitigates the effects of gut injury. METHODS Wistar rats underwent either RYGB (n = 6) or sham procedure (n = 6) and plasma GLP-2, GLP-1, and gut hormone peptide YY (PYY) were measured after 23 days. Biopsies from the terminal ileum were stained using the antibody to Ki67, which detects cyclins and hence demonstrates cells in the S-phase of the cell cycle. The total number of cells, number of mitosis, and number of labeled cells per crypt were counted. Obese patients (n = 6) undergoing RYGB were evaluated following a 420 kcal meal preoperatively, and 1, 3, 6, 12, and 24 months later for responses in l-cell products such as GLP-2, GLP-1, total PYY, and PYY3-36. RESULTS Rat GLP-2 levels after RYGB were elevated 91% above sham animals (P = 0.02). At necropsy, mitotic rate (P < 0.001) and cells positive for the antibody Ki67 (P < 0.001) were increased, indicating crypt cell proliferation. Human GLP-2 after RYGB reached a peak at 6 months of 168% (P < 0.01) above preoperative values. Area under the curve for GLP-1 (P < 0.0001), total PYY (P < 0.01), and PYY3-36 (P < 0.05) responses increased progressively over 24 months. CONCLUSIONS RYGB leads to increased GLP-2 and mucosal crypt cell proliferation. Other gut hormones from l-cells remain elevated for at least 2 years in humans. These findings may account for the restoration of the absorptive surface area of the gut, which limits malabsorption and contributes to the long-term weight loss after RYGB.
Collapse
|
14
|
Kien CL, Blauwiekel R, Bunn JY, Jetton TL, Frankel WL, Holst JJ. Cecal infusion of butyrate increases intestinal cell proliferation in piglets. J Nutr 2007; 137:916-22. [PMID: 17374654 PMCID: PMC1949321 DOI: 10.1093/jn/137.4.916] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The effects of colon-derived butyrate on intestinal cell proliferation are controversial. In vitro studies suggest an inhibitory effect, and in vivo studies suggest the opposite, but neither type of study has been based on a physiologically relevant, intracolonic supply of butyrate. In this study, piglets (n = 24) were fed sow's milk replacement formula and randomized into 4 equal groups: 1) control; 2) cecal butyrate infusion at a rate equal to that produced in the colon; 3) inulin supplementation at a concentration previously found to lower cecal cell proliferation; and 4) butyrate infusion plus inulin supplementation. After 6 d of oral feeding, cecal butyrate infusions were initiated for a period of 4 d. Cecal, distal colonic, jejunal, and ileal cell proliferation, apoptosis, and morphology were evaluated and serum concentration of glucagon-like peptide-2 (GLP-2) was measured. Butyrate or inulin did not affect GLP-2, weight gain, apoptosis, intestinal injury scores, cecal or colon crypt depth, and jejunal or ileal villus height. For cell proliferation, there was a significant interaction between inulin, butyrate, and tissue (P = 0.007). Inulin modified the effect of butyrate (butyrate x inulin interaction in cecum, P = 0.001; in distal colon, P = 0.018; in ileum, P = 0.001; and in jejunum, P = 0.003). In the absence of inulin, butyrate caused a 78- 119% increase in cell proliferation in the ileum, distal colon, jejunum, and cecum (P < or = 0.002). Thus, at an entry rate into the colon within the physiological range, butyrate caused increased intestinal cell proliferation, but inulin tended to block this effect. Thus, intracolonic butyrate may enhance intestinal growth during infancy.
Collapse
Affiliation(s)
- C Lawrence Kien
- Department of Pediatrics, College of Medicine, University of Vermont, Burlington, VT 05405, USA.
| | | | | | | | | | | |
Collapse
|
15
|
Estall JL, Koehler JA, Yusta B, Drucker DJ. The glucagon-like peptide-2 receptor C terminus modulates beta-arrestin-2 association but is dispensable for ligand-induced desensitization, endocytosis, and G-protein-dependent effector activation. J Biol Chem 2005; 280:22124-34. [PMID: 15817468 DOI: 10.1074/jbc.m500078200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Classic models of receptor desensitization and internalization have been largely based on the behavior of Family A G-protein-coupled receptors (GPCRs). The glucagon-like peptide-2 receptor (GLP-2R) is a member of the Family B glucagon-secretin GPCR family, which exhibit significant sequence and structural differences from the Family A receptors in their intracellular and extracellular domains. To identify structural motifs that regulate GLP-2R signaling and cell surface receptor expression, we analyzed the functional properties of a series of mutant GLP-2Rs. The majority of the C-terminal receptor tail was dispensable for GLP-2-induced cAMP accumulation, ERK1/2 activation, and endocytosis in transfected cells. However, progressive truncation of the C terminus reduced cell surface receptor expression, altered agonist-induced GLP-2R trafficking, and abrogated protein kinase A-mediated heterologous receptor desensitization. Elimination of the distal 21 amino acids of the receptor was sufficient to promote constitutive receptor internalization and prevent agonist-induced recruitment of beta-arrestin-2. Site-directed mutagenesis identified specific amino acid residues within the distal GLP-2R C terminus that mediate the stable association with beta-arrestin-2. Surprisingly, although the truncated mutant receptors failed to interact with beta-arrestin-2, they underwent homologous desensitization and subsequent resensitization with kinetics similar to that observed with the wild-type GLP-2R. Our data suggest that, although the GLP-2R C terminus is not required for coupling to cellular machinery regulating signaling or desensitization, it may serve as a sorting signal for intracellular trafficking. Taken together with the previously demonstrated clathrin and dynamin-independent, lipid-raft-dependent pathways for internalization, our data suggest that GLP-2 receptor signaling has evolved unique structural and functional mechanisms for control of receptor trafficking, desensitization, and resensitization.
Collapse
Affiliation(s)
- Jennifer L Estall
- Departments of Laboratory Medicine and Pathobiology, and Medicine, University of Toronto, The Banting and Best Diabetes Centre, Toronto General Hospital, University of Toronto, Toronto M5G 2C4, Canada
| | | | | | | |
Collapse
|
16
|
Koehler JA, Yusta B, Drucker DJ. The HeLa Cell Glucagon-Like Peptide-2 Receptor Is Coupled to Regulation of Apoptosis and ERK1/2 Activation through Divergent Signaling Pathways. Mol Endocrinol 2005; 19:459-73. [PMID: 15471943 DOI: 10.1210/me.2004-0196] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AbstractGlucagon-like peptide-2 (GLP-2) regulates proliferative and cytoprotective pathways in the intestine; however GLP-2 receptor (GLP-2R) signal transduction remains poorly understood, and cell lines that express the endogenous GLP-2R have not yet been isolated. We have now identified several expressed sequence tags from human cervical carcinoma cDNA libraries that correspond to GLP-2R nucleotide sequences. GLP-2R mRNA transcripts were detected by RT-PCR in two human cervical carcinoma cell lines, including HeLa cells. GLP-2 increased cAMP accumulation and activated ERK1/2 in HeLa cells transiently expressing the cloned human HeLa cell GLP-2R cDNA. However, the GLP-2R-induced activation of ERK1/2 was not mediated through Gαs, adenylyl cyclase, or transactivation of the epidermal growth factor receptor, but was pertussis toxin sensitive, inhibited by dominant negative Ras, and dependent on βγ-subunits. GLP-2 also induced a significant increase in bromodeoxyuridine incorporation that was blocked by dominant negative Ras. Furthermore, GLP-2 inhibited HeLa cell apoptosis induced by LY294002 in a protein kinase A-dependent, but ERK-independent, manner. These findings demonstrate that the HeLa cell GLP-2R differentially signals through both Gαs/cAMP- and Gi/Go-dependent pathways, illustrating for the first time that the GLP-2R is capable of coupling to multiple heterotrimeric G proteins defining distinct GLP-2R-dependent biological actions.
Collapse
MESH Headings
- Adenylyl Cyclases/metabolism
- Apoptosis
- Blotting, Southern
- Blotting, Western
- Bromodeoxyuridine/pharmacology
- Cell Line, Tumor
- Cell Survival
- Cervix Uteri/metabolism
- Chromones/pharmacology
- Cloning, Molecular
- Cyclic AMP/metabolism
- DNA/metabolism
- DNA, Complementary/metabolism
- Dimerization
- Dose-Response Relationship, Drug
- Electrophoresis, Polyacrylamide Gel
- Enzyme Activation
- Enzyme Inhibitors/pharmacology
- ErbB Receptors/metabolism
- Female
- Gene Library
- Genes, Dominant
- Glucagon-Like Peptide-1 Receptor
- HeLa Cells
- Humans
- Immunohistochemistry
- Luciferases/metabolism
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3/metabolism
- Models, Biological
- Morpholines/pharmacology
- Pertussis Toxin/pharmacology
- Plasmids/metabolism
- Receptors, Glucagon/chemistry
- Receptors, Glucagon/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction
- Transcriptional Activation
- Transfection
Collapse
Affiliation(s)
- J A Koehler
- Department of Medicine, General Hospital, Banting and Best Diabetes Centre, 200 Elizabeth Street, MBRW4R-402, Toronto, Canada M5G 2C4
| | | | | |
Collapse
|
17
|
Baggio LL, Drucker DJ. Clinical endocrinology and metabolism. Glucagon-like peptide-1 and glucagon-like peptide-2. Best Pract Res Clin Endocrinol Metab 2004; 18:531-54. [PMID: 15533774 DOI: 10.1016/j.beem.2004.08.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The glucagon-like peptides (glucagon-like peptide-1 (GLP-1) and glucagon-like peptide-2 (GLP-2)) are released from enteroendocrine cells in response to nutrient ingestion. GLP-1 enhances glucose-stimulated insulin secretion and inhibits glucagon secretion, gastric emptying and feeding. GLP-1 also has proliferative, neogenic and antiapoptotic effects on pancreatic beta-cells. More recent studies illustrate a potential protective role for GLP-1 in the cardiovascular and central nervous systems. GLP-2 is an intestinal trophic peptide that stimulates cell proliferation and inhibits apoptosis in the intestinal crypt compartment. GLP-2 also regulates intestinal glucose transport, food intake and gastric acid secretion and emptying, and improves intestinal barrier function. Thus, GLP-1 and GLP-2 exhibit a diverse array of metabolic, proliferative and cytoprotective actions with important clinical implications for the treatment of diabetes and gastrointestinal disease, respectively. This review will highlight our current understanding of the biology of GLP-1 and GLP-2, with an emphasis on both well-characterized and more novel therapeutic applications of these peptides.
Collapse
Affiliation(s)
- Laurie L Baggio
- Department of Medicine, The Banting and Best Diabetes Centre, University of Toronto, Toronto General Hospital, 200 Elizabeth Street, MBRW 4R-402, Toronto, Ontario, Canada M5G 2C4
| | | |
Collapse
|
18
|
Burrin D, Guan X, Stoll B, Petersen YM, Sangild PT. Glucagon-like peptide 2: a key link between nutrition and intestinal adaptation in neonates? J Nutr 2004; 133:3712-6. [PMID: 14608101 DOI: 10.1093/jn/133.11.3712] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This paper reviews the evidence from recent studies in young piglets to examine the hypothesis that glucagon-like peptide 2 (GLP-2) is a physiologically relevant hormonal signal linked to the intestinal adaptation associated with enteral nutrition in neonates. Observations that support the hypothesis include, 1) the GLP-2 secretory response to enteral nutrition is functional as early as late gestation, 2) parallel changes in intestinal growth and circulating GLP-2 occur in response to the quantity and composition of enteral nutrition after birth, and 3) the acute temporal changes in intestinal metabolism and circulating GLP-2 concentrations in response to enteral nutrition are generally coincident. In contrast, however, the lack of intestinal trophic responses to both pharmacological GLP-2 concentrations in the fetus and weanling pigs, and to physiological GLP-2 concentrations in neonates raises doubts concerning the physiological relevance of GLP-2 as a enterally mediated trophic signal. A more definitive test of this hypothesis will require further studies that assess the intestinal metabolic response to enteral nutrition using experimental approaches that block GLP-2 action.
Collapse
Affiliation(s)
- Douglas Burrin
- U.S. Department of Agriculture/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
| | | | | | | | | |
Collapse
|