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Neuman JC, Reuter A, Carbajal KA, Schaid MD, Kelly G, Connors K, Kaiser C, Krause J, Hurley LD, Olvera A, Davis DB, Wisinski JA, Gannon M, Kimple ME. The prostaglandin E 2 EP3 receptor has disparate effects on islet insulin secretion and content in β-cells in a high-fat diet-induced mouse model of obesity. Am J Physiol Endocrinol Metab 2024; 326:E567-E576. [PMID: 38477664 DOI: 10.1152/ajpendo.00061.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 02/07/2024] [Accepted: 03/04/2024] [Indexed: 03/14/2024]
Abstract
Signaling through prostaglandin E2 EP3 receptor (EP3) actively contributes to the β-cell dysfunction of type 2 diabetes (T2D). In T2D models, full-body EP3 knockout mice have a significantly worse metabolic phenotype than wild-type controls due to hyperphagia and severe insulin resistance resulting from loss of EP3 in extra-pancreatic tissues, masking any potential beneficial effects of EP3 loss in the β cell. We hypothesized β-cell-specific EP3 knockout (EP3 βKO) mice would be protected from high-fat diet (HFD)-induced glucose intolerance, phenocopying mice lacking the EP3 effector, Gαz, which is much more limited in its tissue distribution. When fed a HFD for 16 wk, though, EP3 βKO mice were partially, but not fully, protected from glucose intolerance. In addition, exendin-4, an analog of the incretin hormone, glucagon-like peptide 1, more strongly potentiated glucose-stimulated insulin secretion in islets from both control diet- and HFD-fed EP3 βKO mice as compared with wild-type controls, with no effect of β-cell-specific EP3 loss on islet insulin content or markers of replication and survival. However, after 26 wk of diet feeding, islets from both control diet- and HFD-fed EP3 βKO mice secreted significantly less insulin as a percent of content in response to stimulatory glucose, with or without exendin-4, with elevated total insulin content unrelated to markers of β-cell replication and survival, revealing severe β-cell dysfunction. Our results suggest that EP3 serves a critical role in temporally regulating β-cell function along the progression to T2D and that there exist Gαz-independent mechanisms behind its effects.NEW & NOTEWORTHY The EP3 receptor is a strong inhibitor of β-cell function and replication, suggesting it as a potential therapeutic target for the disease. Yet, EP3 has protective roles in extrapancreatic tissues. To address this, we designed β-cell-specific EP3 knockout mice and subjected them to high-fat diet feeding to induce glucose intolerance. The negative metabolic phenotype of full-body knockout mice was ablated, and EP3 loss improved glucose tolerance, with converse effects on islet insulin secretion and content.
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Affiliation(s)
- Joshua C Neuman
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Austin Reuter
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Kathryn A Carbajal
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Michael D Schaid
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Grant Kelly
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Kelsey Connors
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Cecilia Kaiser
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Joshua Krause
- Department of Biology, University of Wisconsin-Lacrosse, La Crosse, Wisconsin, United States
| | - Liam D Hurley
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Angela Olvera
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Dawn Belt Davis
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Jaclyn A Wisinski
- Department of Biology, University of Wisconsin-Lacrosse, La Crosse, Wisconsin, United States
| | - Maureen Gannon
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Wisconsin, United States
| | - Michelle E Kimple
- Research Service, William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin, United States
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Kim HT, Desouza AH, Umhoefer H, Han J, Anzia L, Sacotte SJ, Williams RA, Blumer JT, Bartosiak JT, Fontaine DA, Baan M, Kibbe CR, Davis DB. Cholecystokinin attenuates β-cell apoptosis in both mouse and human islets. Transl Res 2022; 243:1-13. [PMID: 34740874 PMCID: PMC9504967 DOI: 10.1016/j.trsl.2021.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 09/23/2021] [Accepted: 10/24/2021] [Indexed: 11/17/2022]
Abstract
Loss of functional pancreatic β-cell mass and increased β-cell apoptosis are fundamental to the pathophysiology of type 1 and type 2 diabetes. Pancreatic islet transplantation has the potential to cure type 1 diabetes but is often ineffective due to the death of the islet graft within the first few years after transplant. Therapeutic strategies to directly target pancreatic β-cell survival are needed to prevent and treat diabetes and to improve islet transplant outcomes. Reducing β-cell apoptosis is also a therapeutic strategy for type 2 diabetes. Cholecystokinin (CCK) is a peptide hormone typically produced in the gut after food intake, with positive effects on obesity and glucose metabolism in mouse models and human subjects. We have previously shown that pancreatic islets also produce CCK. The production of CCK within the islet promotes β-cell survival in rodent models of diabetes and aging. We demonstrate a direct effect of CCK to reduce cytokine-mediated apoptosis in a β-cell line and in isolated mouse islets in a receptor-dependent manner. However, whether CCK can protect human β-cells was previously unknown. Here, we report that CCK can also reduce cytokine-mediated apoptosis in isolated human islets and CCK treatment in vivo decreases β-cell apoptosis in human islets transplanted into the kidney capsule of diabetic NOD/SCID mice. Collectively, these data identify CCK as a novel therapy that can directly promote β-cell survival in human islets and has therapeutic potential to preserve β-cell mass in diabetes and as an adjunct therapy after transplant.
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Affiliation(s)
- Hung Tae Kim
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Arnaldo H Desouza
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Heidi Umhoefer
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Jeeyoung Han
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Lucille Anzia
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Steven J Sacotte
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Rashaun A Williams
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Joseph T Blumer
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Jacob T Bartosiak
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Danielle A Fontaine
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Mieke Baan
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin
| | - Carly R Kibbe
- Department of Human Biology, University of Wisconsin-Green Bay, Green Bay, Wisconsin.
| | - Dawn Belt Davis
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin-Madison, Madison, Wisconsin; William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin.
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Hoyeck MP, Matteo G, MacFarlane EM, Perera I, Bruin JE. Persistent organic pollutants and β-cell toxicity: a comprehensive review. Am J Physiol Endocrinol Metab 2022; 322:E383-E413. [PMID: 35156417 PMCID: PMC9394781 DOI: 10.1152/ajpendo.00358.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/20/2021] [Accepted: 02/07/2022] [Indexed: 01/09/2023]
Abstract
Persistent organic pollutants (POPs) are a diverse family of contaminants that show widespread global dispersion and bioaccumulation. Humans are continuously exposed to POPs through diet, air particles, and household and commercial products; POPs are consistently detected in human tissues, including the pancreas. Epidemiological studies show a modest but consistent correlation between exposure to POPs and increased diabetes risk. The goal of this review is to provide an overview of epidemiological evidence and an in-depth evaluation of the in vivo and in vitro evidence that POPs cause β-cell toxicity. We review evidence for six classes of POPs: dioxins, polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), organophosphate pesticides (OPPs), flame retardants, and per- and polyfluoroalkyl substances (PFAS). The available data provide convincing evidence implicating POPs as a contributing factor driving impaired glucose homeostasis, β-cell dysfunction, and altered metabolic and oxidative stress pathways in islets. These findings support epidemiological data showing that POPs increase diabetes risk and emphasize the need to consider the endocrine pancreas in toxicity assessments. Our review also highlights significant gaps in the literature assessing islet-specific endpoints after both in vivo and in vitro POP exposure. In addition, most rodent studies do not consider the impact of biological sex or secondary metabolic stressors in mediating the effects of POPs on glucose homeostasis and β-cell function. We discuss key gaps and limitations that should be assessed in future studies.
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Affiliation(s)
- Myriam P Hoyeck
- Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
| | - Geronimo Matteo
- Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
| | - Erin M MacFarlane
- Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
| | - Ineli Perera
- Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
| | - Jennifer E Bruin
- Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
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Wang Z, Mohan R, Chen X, Matson K, Waugh J, Mao Y, Zhang S, Li W, Tang X, Satin LS, Tang X. microRNA-483 Protects Pancreatic β-Cells by Targeting ALDH1A3. Endocrinology 2021; 162:6132087. [PMID: 33564883 PMCID: PMC7951052 DOI: 10.1210/endocr/bqab031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Indexed: 12/14/2022]
Abstract
Pancreatic β-cell dysfunction is central to the development and progression of type 2 diabetes. Dysregulation of microRNAs (miRNAs) has been associated with pancreatic islet dysfunction in type 2 diabetes. Previous study has shown that miR-483 is expressed relatively higher in β-cells than in α-cells. To explore the physiological function of miR-483, we generated a β-cell-specific knockout mouse model of miR-483. Loss of miR-483 enhances high-fat diet-induced hyperglycemia and glucose intolerance by the attenuation of diet-induced insulin release. Intriguingly, mice with miR-483 deletion exhibited loss of β-cell features, as indicated by elevated expression of aldehyde dehydrogenase family 1, subfamily A3 (Aldh1a3), a marker of β-cell dedifferentiation. Moreover, Aldh1a3 was validated as a direct target of miR-483 and overexpression of miR-483 repressed Aldh1a3 expression. Genetic ablation of miR-483 also induced alterations in blood lipid profile. Collectively, these data suggest that miR-483 is critical in protecting β-cell function by repressing the β-cell disallowed gene Aldh1a3. The dysregulated miR-483 may impair insulin secretion and initiate β-cell dedifferentiation during the development of type 2 diabetes.
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Affiliation(s)
- Zhihong Wang
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Ramkumar Mohan
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Xinqian Chen
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Katy Matson
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Jackson Waugh
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Yiping Mao
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Shungang Zhang
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Wanzhen Li
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Xiaohu Tang
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
| | - Leslie S Satin
- Department of Pharmacology, Brehm Center for Diabetes, University of Michigan, Ann Arbor, MI, USA
| | - Xiaoqing Tang
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
- Correspondence: Xiaoqing Tang, PhD, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931, USA.
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Pourteymour Fard Tabrizi F, Abbasalizad Farhangi M, Vaezi M, Hemmati S. Changes of body composition and circulating neopterin, omentin-1, and chemerin in response to thylakoid-rich spinach extract with a hypocaloric diet in obese women with polycystic ovary syndrome: A randomized controlled trial. Phytother Res 2021; 35:2594-2606. [PMID: 33368745 DOI: 10.1002/ptr.6999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/25/2020] [Accepted: 12/13/2020] [Indexed: 11/08/2022]
Abstract
This trial evaluated the effects of thylakoid-rich spinach extract supplementation combined with a hypocaloric diet on body composition and serum levels of neopterin, chemerin, and omentin-1 in obese women with polycystic ovary syndrome (PCOS). In this randomized controlled trial, 48 obese women with PCOS, aged 20-45 years old, were recruited and randomly divided into thylakoid (n = 24) and placebo (n = 24) groups. They received a low-calorie diet with 5 g/day thylakoid-rich spinach extract or a low-calorie diet with 5 g/day placebo for 12 weeks. The mean age of the participants of the thylakoid group was 31.86 years, and the placebo group was 32.04 years. Thylakoid-rich spinach extract supplementation with a low-calorie diet increased serum levels of omentin-1 (10.90 vs. 3.87 ng/L; p < .001) and decreased fat mass (-5.19 vs. -1.35 kg; p < .001) and serum levels of neopterin (-0.66 vs. -0.38 nmol/L; p = .003) and chemerin (-41.24 vs. -11.26 ng/L; p < .001) in the thylakoid group compared to the placebo group. A significant improvement in omentin-1, chemerin, and neopterin by thylakoid-rich spinach extract supplementation was under the influence of weight change and insulin resistance status throughout the study. A significant decrease in the other anthropometric indices and insulin resistance was also observed in the thylakoid group, compared to the placebo group (p < .001, for all parameters). Thylakoid-rich spinach extract combined with a low-calorie diet increased circulating omentin-1 and decreased fat mass, abdominal obesity, as well as circulating chemerin, neopterin, and insulin in obese women with PCOS.
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Affiliation(s)
| | - Mahdieh Abbasalizad Farhangi
- Department of Nutrition in Community, Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Maryam Vaezi
- Fellowship Gynecology-Oncology, Women's Reproductive Health Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Obstetrics and Gynecology, Alzahra Teaching Hospital, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Salar Hemmati
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Banerjee S, Woods C, Burnett M, Park SJ, Ja WW, Curtiss J. The Drosophila melanogaster Neprilysin Nepl15 is involved in lipid and carbohydrate storage. Sci Rep 2021; 11:2099. [PMID: 33483521 DOI: 10.1038/s41598-021-81165-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 01/04/2021] [Indexed: 11/09/2022] Open
Abstract
The prototypical M13 peptidase, human Neprilysin, functions as a transmembrane "ectoenzyme" that cleaves neuropeptides that regulate e.g. glucose metabolism, and has been linked to type 2 diabetes. The M13 family has undergone a remarkable, and conserved, expansion in the Drosophila genus. Here, we describe the function of Drosophila melanogaster Neprilysin-like 15 (Nepl15). Nepl15 is likely to be a secreted protein, rather than a transmembrane protein. Nepl15 has changes in critical catalytic residues that are conserved across the Drosophila genus and likely renders the Nepl15 protein catalytically inactive. Nevertheless, a knockout of the Nepl15 gene reveals a reduction in triglyceride and glycogen storage, with the effects likely occurring during the larval feeding period. Conversely, flies overexpressing Nepl15 store more triglycerides and glycogen. Protein modeling suggests that Nepl15 is able to bind and sequester peptide targets of catalytically active Drosophila M13 family members, peptides that are conserved in humans and Drosophila, potentially providing a novel mechanism for regulating the activity of neuropeptides in the context of lipid and carbohydrate homeostasis.
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de Souza AH, Tang J, Yadev AK, Saghafi ST, Kibbe CR, Linnemann AK, Merrins MJ, Davis DB. Intra-islet GLP-1, but not CCK, is necessary for β-cell function in mouse and human islets. Sci Rep 2020; 10:2823. [PMID: 32071395 DOI: 10.1038/s41598-020-59799-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/04/2020] [Indexed: 12/25/2022] Open
Abstract
Glucagon-like peptide 1 (GLP-1) and cholecystokinin (CCK) are gut-derived peptide hormones known to play important roles in the regulation of gastrointestinal motility and secretion, appetite, and food intake. We have previously demonstrated that both GLP-1 and CCK are produced in the endocrine pancreas of obese mice. Interestingly, while GLP-1 is well known to stimulate insulin secretion by the pancreatic β-cells, direct evidence of CCK promoting insulin release in human islets remains to be determined. Here, we tested whether islet-derived GLP-1 or CCK is necessary for the full stimulation of insulin secretion. We confirm that mouse pancreatic islets secrete GLP-1 and CCK, but only GLP-1 acts locally within the islet to promote insulin release ex vivo. GLP-1 is exclusively produced in approximately 50% of α-cells in lean mouse islets and 70% of α-cells in human islets, suggesting a paracrine α to β-cell signaling through the β-cell GLP-1 receptor. Additionally, we provide evidence that islet CCK expression is regulated by glucose, but its receptor signaling is not required during glucose-stimulated insulin secretion (GSIS). We also see no increase in GSIS in response to CCK peptides. Importantly, all these findings were confirmed in islets from non-diabetic human donors. In summary, our data suggest no direct role for CCK in stimulating insulin secretion and highlight the critical role of intra-islet GLP-1 signaling in the regulation of human β-cell function.
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English A, Irwin N. Nonclassical Islet Peptides: Pancreatic and Extrapancreatic Actions. Clin Med Insights Endocrinol Diabetes 2019; 12:1179551419888871. [PMID: 32425629 PMCID: PMC7216561 DOI: 10.1177/1179551419888871] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 10/21/2019] [Indexed: 02/06/2023]
Abstract
The pancreas has physiologically important endocrine and exocrine functions; secreting enzymes into the small intestine to aid digestion and releasing multiple peptide hormones via the islets of Langerhans to regulate glucose metabolism, respectively. Insulin and glucagon, in combination with ghrelin, pancreatic polypeptide and somatostatin, are the main classical islet peptides critical for the maintenance of blood glucose. However, pancreatic islets also synthesis numerous ‘nonclassical’ peptides that have recently been demonstrated to exert fundamental effects on overall islet function and metabolism. As such, insights into the physiological relevance of these nonclassical peptides have shown impact on glucose metabolism, insulin action, cell survival, weight loss, and energy expenditure. This review will focus on the role of individual nonclassical islet peptides to stimulate pancreatic islet secretions as well as regulate metabolism. In addition, the more recognised actions of these peptides on satiety and energy regulation will also be considered. Furthermore, recent advances in the field of peptide therapeutics and obesity-diabetes have focused on the benefits of simultaneously targeting several hormone receptor signalling cascades. The potential for nonclassical islet hormones within such combinational approaches will also be discussed.
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Affiliation(s)
- Andrew English
- School of Pharmacy and Pharmaceutical Sciences, Ulster University, Coleraine, Northern Ireland, UK
| | - Nigel Irwin
- School of Pharmacy and Pharmaceutical Sciences, Ulster University, Coleraine, Northern Ireland, UK
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Mezza T, Cinti F, Cefalo CMA, Pontecorvi A, Kulkarni RN, Giaccari A. β-Cell Fate in Human Insulin Resistance and Type 2 Diabetes: A Perspective on Islet Plasticity. Diabetes 2019; 68:1121-1129. [PMID: 31109941 PMCID: PMC6905483 DOI: 10.2337/db18-0856] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 03/17/2019] [Indexed: 12/23/2022]
Abstract
Although it is well established that type 2 diabetes (T2D) is generally due to the progressive loss of β-cell insulin secretion against a background of insulin resistance, the actual correlation of reduced β-cell mass to its defective function continues to be debated. There is evidence that a compensatory increase in β-cell mass, and the consequent insulin secretion, can effectively cope with states of insulin resistance, until hyperglycemia supervenes. Recent data strongly indicate that the mechanisms by which islets are able to compensate in response to insulin resistance in peripheral tissues is secondary to hyperplasia, as well as the activation of multiple cellular machineries with diverse functions. Importantly, islet cells exhibit plasticity in altering their endocrine commitment; for example, by switching from secretion of glucagon to secretion of insulin and back (transdifferentiation) or from an active secretory state to a nonsecretory quiescent state (dedifferentiation) and back. Lineage tracing (a method used to track each cell though its differentiation process) has demonstrated these potentials in murine models. A limitation to drawing conclusions from human islet research is that most studies are derived from human autopsy and/or organ donor samples, which lack in vivo functional and metabolic profiling. In this review, we specifically focus on evidence of islet plasticity in humans-from the normal state, progressing to insulin resistance to overt T2D-to explain the seemingly contradictory results from different cross-sectional studies in the literature. We hope the discussion on this intriguing scenario will provide a forum for the scientific community to better understand the disease and in the long term pave the way for personalized therapies.
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Affiliation(s)
- Teresa Mezza
- U.O.C. Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italia
- Istituto di Patologia Speciale Medica e Semeiotica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Francesca Cinti
- U.O.C. Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italia
- Istituto di Patologia Speciale Medica e Semeiotica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Chiara Maria Assunta Cefalo
- U.O.C. Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italia
- Istituto di Patologia Speciale Medica e Semeiotica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Alfredo Pontecorvi
- U.O.C. Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italia
- Istituto di Patologia Speciale Medica e Semeiotica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Rohit N Kulkarni
- Islet Cell & Regenerative Biology, Joslin Diabetes Center and Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Andrea Giaccari
- U.O.C. Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italia
- Istituto di Patologia Speciale Medica e Semeiotica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
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Wu Q, Ni H, Lu X. Changes of adipocytokine expression after diabetic rats received sitagliptin and the molecular mechanism. ASIAN PAC J TROP MED 2016; 9:893-7. [DOI: 10.1016/j.apjtm.2016.07.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 06/16/2016] [Accepted: 07/01/2016] [Indexed: 11/23/2022] Open
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