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Hill TG, Hill DJ. The Importance of Intra-Islet Communication in the Function and Plasticity of the Islets of Langerhans during Health and Diabetes. Int J Mol Sci 2024; 25:4070. [PMID: 38612880 PMCID: PMC11012451 DOI: 10.3390/ijms25074070] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/27/2024] [Accepted: 03/27/2024] [Indexed: 04/14/2024] Open
Abstract
Islets of Langerhans are anatomically dispersed within the pancreas and exhibit regulatory coordination between islets in response to nutritional and inflammatory stimuli. However, within individual islets, there is also multi-faceted coordination of function between individual beta-cells, and between beta-cells and other endocrine and vascular cell types. This is mediated partly through circulatory feedback of the major secreted hormones, insulin and glucagon, but also by autocrine and paracrine actions within the islet by a range of other secreted products, including somatostatin, urocortin 3, serotonin, glucagon-like peptide-1, acetylcholine, and ghrelin. Their availability can be modulated within the islet by pericyte-mediated regulation of microvascular blood flow. Within the islet, both endocrine progenitor cells and the ability of endocrine cells to trans-differentiate between phenotypes can alter endocrine cell mass to adapt to changed metabolic circumstances, regulated by the within-islet trophic environment. Optimal islet function is precariously balanced due to the high metabolic rate required by beta-cells to synthesize and secrete insulin, and they are susceptible to oxidative and endoplasmic reticular stress in the face of high metabolic demand. Resulting changes in paracrine dynamics within the islets can contribute to the emergence of Types 1, 2 and gestational diabetes.
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Affiliation(s)
- Thomas G. Hill
- Oxford Centre for Diabetes, Endocrinology, and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - David J. Hill
- Lawson Health Research Institute, St. Joseph’s Health Care, London, ON N6A 4V2, Canada;
- Departments of Medicine, Physiology and Pharmacology, Western University, London, ON N6A 3K7, Canada
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2
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Trotta MC, Gesualdo C, Russo M, Lepre CC, Petrillo F, Vastarella MG, Nicoletti M, Simonelli F, Hermenean A, D’Amico M, Rossi S. Changes in Circulating Acylated Ghrelin and Neutrophil Elastase in Diabetic Retinopathy. Medicina (Kaunas) 2024; 60:118. [PMID: 38256379 PMCID: PMC10820226 DOI: 10.3390/medicina60010118] [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] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/04/2024] [Accepted: 01/05/2024] [Indexed: 01/24/2024]
Abstract
Background and Objectives: The role and the levels of ghrelin in diabetes-induced retinal damage have not yet been explored. The present study aimed to measure the serum levels of total ghrelin (TG), and its acylated (AG) and des-acylated (DAG) forms in patients with the two stages of diabetic retinopathy (DR), non-proliferative (NPDR) and proliferative (PDR). Moreover, the correlation between serum ghrelin and neutrophil elastase (NE) levels was investigated. Materials and Methods: The serum markers were determined via enzyme-linked immunosorbent assays in 12 non-diabetic subjects (CTRL), 15 diabetic patients without DR (Diabetic), 15 patients with NPDR, and 15 patients with PDR. Results: TG and AG serum levels were significantly decreased in Diabetic (respectively, p < 0.05 and p < 0.01 vs. CTRL), NPDR (p < 0.01 vs. Diabetic), and in PDR patients (p < 0.01 vs. NPDR). AG serum levels were inversely associated with DR abnormalities (microhemorrhages, microaneurysms, and exudates) progression (r = -0.83, p < 0.01), serum neutrophil percentage (r = -0.74, p < 0.01), and serum NE levels (r = -0.73, p < 0.01). The latter were significantly increased in the Diabetic (p < 0.05 vs. CTRL), NPDR (p < 0.01 vs. Diabetic), and PDR (p < 0.01 vs. PDR) groups. Conclusions: The two DR stages were characterized by decreased AG and increased NE levels. In particular, serum AG levels were lower in PDR compared to NPDR patients, and serum NE levels were higher in the PDR vs. the NPDR group. Together with the greater presence of retinal abnormalities, this could underline a distinctive role of AG in PDR compared to NPDR.
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Affiliation(s)
- Maria Consiglia Trotta
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (M.C.T.); (C.C.L.); (F.P.); (M.D.)
| | - Carlo Gesualdo
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (C.G.); (M.N.); (F.S.)
| | - Marina Russo
- PhD Course in National Interest in Public Administration and Innovation for Disability and Social Inclusion, Department of Mental, Physical Health and Preventive Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy;
- School of Pharmacology and Clinical Toxicology, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Caterina Claudia Lepre
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (M.C.T.); (C.C.L.); (F.P.); (M.D.)
- PhD Course in Translational Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy;
| | - Francesco Petrillo
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (M.C.T.); (C.C.L.); (F.P.); (M.D.)
- PhD Course in Translational Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy;
| | - Maria Giovanna Vastarella
- PhD Course in Translational Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy;
| | - Maddalena Nicoletti
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (C.G.); (M.N.); (F.S.)
| | - Francesca Simonelli
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (C.G.); (M.N.); (F.S.)
| | - Anca Hermenean
- “Aurel Ardelean” Institute of Life Sciences, Vasile Goldis Western University of Arad, 310144 Arad, Romania;
| | - Michele D’Amico
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (M.C.T.); (C.C.L.); (F.P.); (M.D.)
| | - Settimio Rossi
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (C.G.); (M.N.); (F.S.)
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3
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Wang R, Wang Y, Qin Y, Wei H. Antioxidative effects of ghrelin on human trabecular meshwork cells. J Fr Ophtalmol 2024; 47:103746. [PMID: 37806937 DOI: 10.1016/j.jfo.2022.11.023] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 10/31/2022] [Accepted: 11/11/2022] [Indexed: 10/10/2023]
Abstract
Glaucoma is a group of neurodegenerative diseases characterized by loss of retinal ganglion cells and visual field defects and is one of the major causes of irreversible blindness worldwide. Primary open-angle glaucoma (POAG) is one of the classifications of glaucoma. Oxidative stress in trabecular reticulated cells is one of the possible mechanisms of the development of glaucoma. At present, there is still a lack of effective methods to treat glaucoma. Ghrelin is characterized by its wide distribution and high potency and has anti-inflammatory, antioxidant, and anti-apoptotic effects, which may be beneficial in the treatment of glaucoma. In this study, we investigated whether ghrelin can protect human trabecular meshwork cells (HTMCs) from oxidative damage induced by hydrogen peroxide (H2O2), as well as the possible mechanism of action. CCK8 and flow cytometry results revealed that treatment of HTMCs with ghrelin showed a dose-dependent protective effect against H2O2-induced damage. Ghrelin significantly decreased the rate of apoptosis and levels of reactive oxygen species (ROS) and malondialdehyde (MDA) and increased the level of superoxide dismutase (SOD) and catalase (CAT) in HTMCs. The difference was statistically significant compared with the H2O2 group. Ghrelin activated Nrf2/HO-1/NQO-1 signaling pathways and decreased HIF-1α level in H2O2-injured HTMCs as shown on qPCR and Western blot. In conclusion, ghrelin can protect HTMCs from oxidative damage induced by H2O2 and reduce apoptosis in HTMCs, which can be a new approach to treating POAG. The underlying therapeutic mechanism may be related to Nrf2/HO-1/NQO-1 signaling pathways and HIF-1α.
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Affiliation(s)
- R Wang
- Eye Hospital, the First Affiliated Hospital of Harbin Medical University, Key Laboratory of Basic and Clinical Research of Heilongjiang Province, Harbin, China.
| | - Y Wang
- Eye Hospital, the First Affiliated Hospital of Harbin Medical University, Key Laboratory of Basic and Clinical Research of Heilongjiang Province, Harbin, China
| | - Y Qin
- Eye Hospital, the First Affiliated Hospital of Harbin Medical University, Key Laboratory of Basic and Clinical Research of Heilongjiang Province, Harbin, China
| | - H Wei
- Eye Hospital, the First Affiliated Hospital of Harbin Medical University, Key Laboratory of Basic and Clinical Research of Heilongjiang Province, Harbin, China.
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Gupta D, Burstein AW, Schwalbe DC, Shankar K, Varshney S, Singh O, Paul S, Ogden SB, Osborne-Lawrence S, Metzger NP, Richard CP, Campbell JN, Zigman JM. Ghrelin deletion and conditional ghrelin cell ablation increase pancreatic islet size in mice. J Clin Invest 2023; 133:e169349. [PMID: 38099492 PMCID: PMC10721155 DOI: 10.1172/jci169349] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 10/05/2023] [Indexed: 12/18/2023] Open
Abstract
Ghrelin exerts key effects on islet hormone secretion to regulate blood glucose levels. Here, we sought to determine whether ghrelin's effects on islets extend to the alteration of islet size and β cell mass. We demonstrate that reducing ghrelin - by ghrelin gene knockout (GKO), conditional ghrelin cell ablation, or high-fat diet (HFD) feeding - was associated with increased mean islet size (up to 62%), percentage of large islets (up to 854%), and β cell cross-sectional area (up to 51%). In GKO mice, these effects were more apparent in 10- to 12-week-old mice than in 4-week-old mice. Higher β cell numbers from decreased β cell apoptosis drove the increase in β cell cross-sectional area. Conditional ghrelin cell ablation in adult mice increased the β cell number per islet by 40% within 4 weeks. A negative correlation between islet size and plasma ghrelin in HFD-fed plus chow-fed WT mice, together with even larger islet sizes in HFD-fed GKO mice than in HFD-fed WT mice, suggests that reduced ghrelin was not solely responsible for diet-induced obesity-associated islet enlargement. Single-cell transcriptomics revealed changes in gene expression in several GKO islet cell types, including upregulation of Manf, Dnajc3, and Gnas expression in β cells, which supports decreased β cell apoptosis and/or increased β cell proliferation. These effects of ghrelin reduction on islet morphology might prove useful when designing new therapies for diabetes.
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Affiliation(s)
- Deepali Gupta
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Avi W. Burstein
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Dana C. Schwalbe
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Kripa Shankar
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Salil Varshney
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Omprakash Singh
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Subhojit Paul
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Sean B. Ogden
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Sherri Osborne-Lawrence
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Nathan P. Metzger
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Corine P. Richard
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - John N. Campbell
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Jeffrey M. Zigman
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
- Division of Endocrinology and Metabolism, Department of Internal Medicine and
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas, USA
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5
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Roberts FL, Cataldo LR, Fex M. Monoamines' role in islet cell function and type 2 diabetes risk. Trends Mol Med 2023; 29:1045-1058. [PMID: 37722934 DOI: 10.1016/j.molmed.2023.08.009] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/22/2023] [Accepted: 08/25/2023] [Indexed: 09/20/2023]
Abstract
The two monoamines serotonin and melatonin have recently been highlighted as potent regulators of islet hormone secretion and overall glucose homeostasis in the body. In fact, dysregulated signaling of both amines are implicated in β-cell dysfunction and development of type 2 diabetes mellitus (T2DM). Serotonin is a key player in β-cell physiology and plays a role in expansion of β-cell mass. Melatonin regulates circadian rhythm and nutrient metabolism and reduces insulin release in human and rodent islets in vitro. Herein, we focus on the role of serotonin and melatonin in islet physiology and the pathophysiology of T2DM. This includes effects on hormone secretion, receptor expression, genetic variants influencing β-cell function, melatonin treatment, and compounds that alter serotonin availability and signaling.
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Affiliation(s)
- Fiona Louise Roberts
- Lund University Diabetes Centre, Department of Clinical Sciences, Unit for Molecular Metabolism, SE-21428 Malmö, Sweden
| | - Luis Rodrigo Cataldo
- Lund University Diabetes Centre, Department of Clinical Sciences, Unit for Molecular Metabolism, SE-21428 Malmö, Sweden; The Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, DK-2200, Denmark
| | - Malin Fex
- Lund University Diabetes Centre, Department of Clinical Sciences, Unit for Molecular Metabolism, SE-21428 Malmö, Sweden.
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Gajewska A, Strzelecki D, Gawlik-Kotelnicka O. Ghrelin as a Biomarker of "Immunometabolic Depression" and Its Connection with Dysbiosis. Nutrients 2023; 15:3960. [PMID: 37764744 PMCID: PMC10537261 DOI: 10.3390/nu15183960] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 09/08/2023] [Accepted: 09/10/2023] [Indexed: 09/29/2023] Open
Abstract
Ghrelin, a gastrointestinal peptide, is an endogenous ligand of growth hormone secretagogue receptor 1a (GHSR1a), which is mainly produced by X/A-like cells in the intestinal mucosa. Beyond its initial description as a growth hormone (GH) secretagogue stimulator of appetite, ghrelin has been revealed to have a wide range of physiological effects, for example, the modulation of inflammation; the improvement of cardiac performance; the modulation of stress, anxiety, taste sensation, and reward-seeking behavior; and the regulation of glucose metabolism and thermogenesis. Ghrelin secretion is altered in depressive disorders and metabolic syndrome, which frequently co-occur, but it is still unknown how these modifications relate to the physiopathology of these disorders. This review highlights the increasing amount of research establishing the close relationship between ghrelin, nutrition, microbiota, and disorders such as depression and metabolic syndrome, and it evaluates the ghrelinergic system as a potential target for the development of effective pharmacotherapies.
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Affiliation(s)
- Agata Gajewska
- Faculty of Medicine, Medical University of Lodz, 92-216 Lodz, Poland;
| | - Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Lodz, 92-216 Lodz, Poland;
| | - Oliwia Gawlik-Kotelnicka
- Department of Affective and Psychotic Disorders, Medical University of Lodz, 92-216 Lodz, Poland;
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Liu Y, Bharmal SH, Kimita W, Petrov MS. Effect of d-β-Hydroxybutyrate-(R)-1,3 Butanediol on Appetite Regulation in People with Prediabetes. Mol Nutr Food Res 2023; 67:e2200615. [PMID: 36565045 DOI: 10.1002/mnfr.202200615] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/22/2022] [Indexed: 12/25/2022]
Abstract
SCOPE The main aim of the present study is to study the effect of acute ketosis on parameters of appetite regulation in prediabetes. METHODS AND RESULTS This is a randomized controlled trial registered under ClinicalTrials.gov identifier NCT03889210. After an overnight fast, 18 adults with prediabetes are assigned to consume a ketone monoester (d-β-hydroxybutyrate-(R)-1,3 butanediol) drink and a placebo drink in cross-over fashion. Blood samples are collected every 30 min, from baseline to 150 min. Paired t test is used to compare the total area under the curve (AUC) for the changes in parameters of appetite regulation (acylated ghrelin, peptide YY [PYY], and hunger) following both drinks. Significant elevation in blood β-hydroxybutyrate from 0.2 to 3.5 mmol L-1 (p < 0.001) is achieved within 30 min. Acute ketosis does not result in statistically significant differences in the AUCs for ghrelin, PYY, and hunger. CONCLUSION Acute ketosis consistently does not affect both objective and subjective parameters of appetite regulation in prediabetes.
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Affiliation(s)
- Yutong Liu
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
| | - Sakina H Bharmal
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
| | - Wandia Kimita
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
| | - Maxim S Petrov
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
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Catalano F, De Vito F, Cassano V, Fiorentino TV, Sciacqua A, Hribal ML. Circadian Clock Desynchronization and Insulin Resistance. Int J Environ Res Public Health 2022; 20:29. [PMID: 36612350 PMCID: PMC9819930 DOI: 10.3390/ijerph20010029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/09/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
The circadian rhythm regulates biological processes that occur within 24 h in living organisms. It plays a fundamental role in maintaining biological functions and responds to several inputs, including food intake, light/dark cycle, sleep/wake cycle, and physical activity. The circadian timing system comprises a central clock located in the suprachiasmatic nucleus (SCN) and tissue-specific clocks in peripheral tissues. Several studies show that the desynchronization of central and peripheral clocks is associated with an increased incidence of insulin resistance (IR) and related diseases. In this review, we discuss the current knowledge of molecular and cellular mechanisms underlying the impact of circadian clock dysregulation on insulin action. We focus our attention on two possible mediators of this interaction: the phosphatases belonging to the pleckstrin homology leucine-rich repeat protein phosphatase family (PHLPP) family and the deacetylase Sirtuin1. We believe that literature data, herein summarized, suggest that a thorough change of life habits, with the return to synchronized food intake, physical activity, and rest, would doubtless halt the vicious cycle linking IR to dysregulated circadian rhythms. However, since such a comprehensive change may be incompatible with the demand of modern society, clarifying the pathways involved may, nonetheless, contribute to the identification of therapeutic targets that may be exploited to cure or prevent IR-related diseases.
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Abstract
Islet dysfunction is central in type 2 diabetes and full-blown type 2 diabetes develops first when the beta cells lose their ability to secrete adequate amounts of insulin in response to raised plasma glucose. Several mechanisms behind beta cell dysfunction have been put forward but many important questions still remain. Furthermore, our understanding of the contribution of each islet cell type in type 2 diabetes pathophysiology has been limited by technical boundaries. Closing this knowledge gap will lead to a leap forward in our understanding of the islet as an organ and potentially lead to improved treatments. The development of single-cell RNA sequencing (scRNAseq) has led to a breakthrough for characterising the transcriptome of each islet cell type and several important observations on the regulation of cell-type-specific gene expression have been made. When it comes to identifying type 2 diabetes disease mechanisms, the outcome is still limited. Several studies have identified differentially expressed genes, although there is very limited consensus between the studies. As with all new techniques, scRNAseq has limitations; in addition to being extremely expensive, genes expressed at low levels may not be detected, noise may not be appropriately filtered and selection biases for certain cell types are at hand. Furthermore, recent advances suggest that commonly used computational tools may be suboptimal for analysis of scRNAseq data in small-scale studies. Fortunately, development of new computational tools holds promise for harnessing the full potential of scRNAseq data. Here we summarise how scRNAseq has contributed to increasing the understanding of various aspects of islet biology as well as type 2 diabetes disease mechanisms. We also focus on challenges that remain and propose steps to promote the utilisation of the full potential of scRNAseq in this area.
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Affiliation(s)
| | - Nils Wierup
- Lund University Diabetes Centre, Malmö, Sweden.
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10
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Li J, Huang P, Xiong J, Liang X, Li M, Ke H, Chen C, Han Y, Huang Y, Zhou Y, Luo Z, Feng D, Chen C. Serum levels of ghrelin and LEAP2 in patients with type 2 diabetes mellitus: correlation with circulating glucose and lipids. Endocr Connect 2022; 11:e220012. [PMID: 35521798 PMCID: PMC9175609 DOI: 10.1530/ec-22-0012] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 04/26/2022] [Indexed: 11/08/2022]
Abstract
Objective Ghrelin regulates body weight, food intake, and blood glucose. It also regulates insulin secretion from pancreatic islet cells. LEAP2 is a newly discovered endogenous ligand of the growth hormone secretagogue's receptor (GHSR). It not only antagonizes the stimulation of GHSR by ghrelin but also inhibits the constitutive activation of GHSR as an inverse agonist. Type 2 diabetes (T2D) patients have endocrine disorders with metabolic imbalance. Plasma levels of ghrelin and LEAP2 may be changed in obese and T2D patients. However, there is no report yet on circulating LEAP2 levels or ghrelin/LEAP2 ratio in T2D patients. In this study, fasting serum ghrelin and LEAP2 levels in healthy adults and T2D patients were assessed to clarify the association of two hormones with different clinical anthropometric and metabolic parameters. Design A total of 16 females and 40 males, ages 23-68 years old normal (n = 27), and T2D patients (n = 29) were enrolled as a cross-sectional cohort. Results Serum levels of ghrelin were lower but serum levels of LEAP2 were higher in T2D patients. Ghrelin levels were positively correlated with fasting serum insulin levels and HOMA-IR in healthy adults. LEAP2 levels were positively correlated with age and hemoglobin A1c (HbA1c) in all tested samples. Ghrelin/LEAP2 ratio was negatively correlated with age, fasting blood glucose, and HbA1c. Conclusions This study demonstrated a decrease in serum ghrelin levels and an increase in serum LEAP2 levels in T2D patients. LEAP2 levels were positively correlated with HbA1c, suggesting that LEAP2 was associated with T2D development. The ghrelin/LEAP2 ratio was closely associated with glycemic control in T2D patients showing a negative correlation with glucose and HbA1c.
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Affiliation(s)
- Jiaxi Li
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Pu Huang
- Department of Health Management Center, Changsha Central Hospital, University of South China, Changsha, Hunan, China
| | - Jing Xiong
- Department of Endocrinology, Xiangya Third Hospital, Central South University, Changsha, Hunan, China
| | - Xinyue Liang
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Mei Li
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Hao Ke
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Chunli Chen
- Department of Dermatology, Xiangya Third Hospital, Central South University, Changsha, Hunan, China
| | - Yang Han
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Yanhong Huang
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Yan Zhou
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Ziqiang Luo
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Organ Fibrosis, Central South University, Changsha, Hunan, China
| | - Dandan Feng
- Department of Physiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Organ Fibrosis, Central South University, Changsha, Hunan, China
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, Queensland, Australia
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11
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Thor D. G protein-coupled receptors as regulators of pancreatic islet functionality. Biochim Biophys Acta Mol Cell Res 2022; 1869:119235. [PMID: 35151663 DOI: 10.1016/j.bbamcr.2022.119235] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 01/03/2023]
Abstract
Glucose homeostasis is maintained by hormones secreted from different types of pancreatic islets and its dysregulation can result in diseases including diabetes mellitus. The secretion of hormones from pancreatic islets is highly complex and tightly controlled by G protein-coupled receptors (GPCRs). Moreover, GPCR signaling may play a role in enhancing islet cell replication and proliferation. Thus, targeting GPCRs offers a promising strategy for regulating the functionality of pancreatic islets. Here, available RNAseq datasets from human and mouse islets were used to identify the GPCR expression profile and the impact of GPCR signaling for normal islet functionality is discussed.
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Affiliation(s)
- Doreen Thor
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, Leipzig University, Johannisallee 30, 04103 Leipzig, Germany.
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Peiu SN, Popa RF, Akad F, Cretu-silivestru IS, Mihai BM, Visnevschi A, Vudu L, Tamba B, Oboroceanu T, Timofte D, Mocanu V. Perivascular Adipose Tissue Inflammation: The Anti-Inflammatory Role of Ghrelin in Atherosclerosis Progression. Applied Sciences 2022; 12:3307. [DOI: 10.3390/app12073307] [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] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Perivascular adipose tissue (PVAT) and its adipokines engage in bidirectional crosstalk with the vascular wall. Atherosclerosis disrupts this interaction through inflammation, rupture-prone plaques, and subsequent thrombosis. The cardioprotective effects of ghrelin are in contradiction to its adipogenic properties. The concurrent research of anti-/pro-atherogenic mechanisms of ghrelin and PVAT-derived adipokines provides a better understanding of atherosclerosis progression in metabolic disorders. In-depth coverage of the characteristic features of PVAT concerning vascular dysfunction, with a survey of ghrelin-induced anti-inflammatory effects on adipose tissue macrophage infiltration and the inhibitory activity of ghrelin on the proinflammatory adipokine secretion, show that the impact of ghrelin on the endothelial function should be studied in relation to PVAT.
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Chen X, Dong J, Jiao Q, Du X, Bi M, Jiang H. "Sibling" battle or harmony: crosstalk between nesfatin-1 and ghrelin. Cell Mol Life Sci 2022; 79:169. [PMID: 35239020 DOI: 10.1007/s00018-022-04193-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 12/17/2022]
Abstract
Ghrelin was first identified as an endogenous ligand of the growth hormone secretagogue receptor (GHSR) in 1999, with the function of stimulating the release of growth hormone (GH), while nesfatin-1 was identified in 2006. Both peptides are secreted by the same kind of endocrine cells, X/A-like cells in the stomach. Compared with ghrelin, nesfatin-1 exerts opposite effects on energy metabolism, glucose metabolism, gastrointestinal functions and regulation of blood pressure, but exerts similar effects on anti-inflammation and neuroprotection. Up to now, nesfatin-1 remains as an orphan ligand because its receptor has not been identified. Several studies have shown the effects of nesfatin-1 are dependent on the receptor of ghrelin. We herein compare the effects of nesfatin-1 and ghrelin in several aspects and explore the possibility of their interactions.
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Affiliation(s)
- Xi Chen
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Qingdao University, Qingdao, 266071, People's Republic of China
| | - Jing Dong
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Qingdao University, Qingdao, 266071, People's Republic of China
| | - Qian Jiao
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Qingdao University, Qingdao, 266071, People's Republic of China
| | - Xixun Du
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Qingdao University, Qingdao, 266071, People's Republic of China
| | - Mingxia Bi
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Qingdao University, Qingdao, 266071, People's Republic of China
| | - Hong Jiang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Qingdao University, Qingdao, 266071, People's Republic of China.
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14
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Dezaki K, Yada T. Status of ghrelin as an islet hormone and paracrine/autocrine regulator of insulin secretion. Peptides 2022; 148:170681. [PMID: 34728253 DOI: 10.1016/j.peptides.2021.170681] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/06/2021] [Accepted: 10/28/2021] [Indexed: 12/20/2022]
Abstract
Ghrelin is expressed in the pancreatic islet cells as well as the stomach. In the perfused pancreas and isolated islets, GHS-R antagonism, ghrelin immunoneutralization and ghrelin-knockout (Ghr-KO) all increase glucose-induced insulin release. Thus, pharmacological, immunological and genetic blockades of ghrelin in the pancreatic islets all markedly augment glucose-induced insulin release, showing that islet-derived ghrelin physiologically restricts insulin release in rodents. In this review, we focus on the current understanding of the following key questions: 1) from which islet cells ghrelin is released, 2) on which islet cells ghrelin acts, and 3) mechanisms by which the islet-derived ghrelin inhibits insulin secretion.
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Affiliation(s)
- Katsuya Dezaki
- Iryo Sosei University, Faculty of Pharmacy, 5-5-1, Chuodai Iino, Iwaki, Fukushima, 970-8551, Japan.
| | - Toshihiko Yada
- Kansai Electric Power Medical Research Institute, Center for Integrative Physiology, Division of Integrative Physiology, 1-5-6 Minatojimaminamimachi, Chuo-ku, Kobe, 650-0047, Japan; Division of Diabetes, Metabolism and Endocrinology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-Cho, Chuo-Ku, Kobe, 650-0017, Japan.
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15
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Sitar-Tǎut AV, Cozma A, Fodor A, Coste SC, Orasan OH, Negrean V, Pop D, Sitar-Tǎut DA. New Insights on the Relationship between Leptin, Ghrelin, and Leptin/Ghrelin Ratio Enforced by Body Mass Index in Obesity and Diabetes. Biomedicines 2021; 9:biomedicines9111657. [PMID: 34829886 PMCID: PMC8615809 DOI: 10.3390/biomedicines9111657] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/18/2021] [Accepted: 11/08/2021] [Indexed: 12/12/2022] Open
Abstract
Currently, adipose tissue is considered an endocrine organ, however, there are still many questions regarding the roles of adipokines—leptin and ghrelin being two adipokines. The purpose of the study was to assess the relationship between the adipokines and their ratio with obesity and diabetes. Methods: Sixty patients (mean age 61.88 ± 10.08) were evaluated. Cardiovascular risk factors, leptin, ghrelin, and insulin resistance score values were assessed. The patients were classified according to their body mass index (BMI) as normal weight, overweight, and obese. Results: 20% normal weight, 51.7% overweight, 28.3% obese, and 23.3% diabetic. Obese patients had higher leptin values (in obese 34,360 pg/mL vs. overweight 18,000 pg/mL vs. normal weight 14,350 pg/mL, p = 0.0049) and leptin/ghrelin ratio (1055 ± 641 vs. 771.36 ± 921 vs. 370.7 ± 257, p = 0.0228). Stratifying the analyses according to the presence of obesity and patients’ gender, differences were found for leptin (p = 0.0020 in women, p = 0.0055 in men) and leptin/ghrelin ratio (p = 0.048 in women, p = 0.004 in men). Mean leptin/BMI and leptin/ghrelin/BMI ratios were significantly higher, and the ghrelin/BMI ratio was significantly lower in obese and diabetic patients. In conclusion, obesity and diabetes are associated with changes not only in the total amount but also in the level of adipokines/kg/m2. Changes appear even in overweight subjects, offering a basis for early intervention in diabetic and obese patients.
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Affiliation(s)
- Adela-Viviana Sitar-Tǎut
- Internal Medicine Department, 4th Medical Clinic, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (A.C.); (S.-C.C.); (O.H.O.); (V.N.)
- Correspondence:
| | - Angela Cozma
- Internal Medicine Department, 4th Medical Clinic, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (A.C.); (S.-C.C.); (O.H.O.); (V.N.)
| | - Adriana Fodor
- Clinical Center of Diabetes, Nutrition, Metabolic Diseases, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania;
| | - Sorina-Cezara Coste
- Internal Medicine Department, 4th Medical Clinic, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (A.C.); (S.-C.C.); (O.H.O.); (V.N.)
| | - Olga Hilda Orasan
- Internal Medicine Department, 4th Medical Clinic, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (A.C.); (S.-C.C.); (O.H.O.); (V.N.)
| | - Vasile Negrean
- Internal Medicine Department, 4th Medical Clinic, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (A.C.); (S.-C.C.); (O.H.O.); (V.N.)
| | - Dana Pop
- Department of Cardiology, Clinical Rehabilitation Hospital, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania;
| | - Dan-Andrei Sitar-Tǎut
- Business Information Systems Department, Faculty of Economics and Business Administration 58-60 Theodor Mihaly Street, “Babeş-Bolyai” University, 400591 Cluj-Napoca, Romania;
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16
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Ginter G, Ceranowicz P, Warzecha Z. Protective and Healing Effects of Ghrelin and Risk of Cancer in the Digestive System. Int J Mol Sci 2021; 22:10571. [PMID: 34638910 DOI: 10.3390/ijms221910571] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 09/24/2021] [Accepted: 09/27/2021] [Indexed: 01/19/2023] Open
Abstract
Ghrelin is an endogenous ligand for the ghrelin receptor, previously known as the growth hormone secretagogue receptor. This hormone is mainly produced by endocrine cells present in the gastric mucosa. The ghrelin-producing cells are also present in other organs of the body, mainly in the digestive system, but in much smaller amount. Ghrelin exhibits a broad spectrum of physiological effects, such as stimulation of growth hormone secretion, gastric secretion, gastrointestinal motility, and food intake, as well as regulation of glucose homeostasis and bone formation, and inhibition of inflammatory processes. This review summarizes the recent findings concerning animal and human data showing protective and therapeutic effects of ghrelin in the gut, and also presents the role of growth hormone and insulin-like growth factor-1 in these effects. In addition, the current data on the possible influence of ghrelin on the carcinogenesis, its importance in predicting the risk of developing gastrointestinal malignances, as well as the potential usefulness of ghrelin in the treatment of cancer, have been presented.
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Nunez‐Salces M, Li H, Feinle‐Bisset C, Young RL, Page AJ. The regulation of gastric ghrelin secretion. Acta Physiol (Oxf) 2021; 231:e13588. [PMID: 33249751 DOI: 10.1111/apha.13588] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/19/2020] [Accepted: 11/23/2020] [Indexed: 12/13/2022]
Abstract
Ghrelin is a gastric hormone with multiple physiological functions, including the stimulation of food intake and adiposity. It is well established that circulating ghrelin levels are closely associated with feeding patterns, rising strongly before a meal and lowering upon food intake. However, the mechanisms underlying the modulation of ghrelin secretion are not fully understood. The purpose of this review is to discuss current knowledge on the circadian oscillation of circulating ghrelin levels, the neural mechanisms stimulating fasting ghrelin levels and peripheral mechanisms modulating postprandial ghrelin levels. Furthermore, the therapeutic potential of targeting the ghrelin pathway is discussed in the context of the treatment of various metabolic disorders, including obesity, type 2 diabetes, diabetic gastroparesis and Prader-Willi syndrome. Moreover, eating disorders including anorexia nervosa, bulimia nervosa and binge-eating disorder are also discussed.
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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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18
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Abstract
Insulin secretion by β-cells is largely controlled by circulating nutrients, hormones, and neurotransmitters. However, recent years have witnessed the multiplication of studies investigating whether local regulation also takes place within pancreatic islets, in which β-cells cohabit with several other cell types. The cell composition and architectural organization of human islets differ from those of rodent islets and are particularly favorable to cellular interactions. An impressive number of hormonal (glucagon, glucagon-like peptide-1, somatostatin, etc.) and nonhormonal products (ATP, acetylcholine, γ-aminobutyric acid, dopamine, etc.) are released by islet cells and have been implicated in a local control of insulin secretion. This review analyzes reports directly testing paracrine and autocrine control of insulin secretion in isolated human islets. Many of these studies were designed on background information collected in rodent islets. However, the perspective of the review is not to highlight species similarities or specificities but to contrast established and speculative mechanisms in human islets. It will be shown that the current evidence is convincing only for a minority of candidates for a paracrine function whereas arguments supporting a physiological role of others do not stand up to scrutiny. Several pending questions await further investigation.
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Affiliation(s)
- Jean-Claude Henquin
- Unit of Endocrinology and Metabolism, Faculty of Medicine, University of Louvain, Brussels, Belgium
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19
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Lu X, Huang L, Huang Z, Feng D, Clark RJ, Chen C. LEAP-2: An Emerging Endogenous Ghrelin Receptor Antagonist in the Pathophysiology of Obesity. Front Endocrinol (Lausanne) 2021; 12:717544. [PMID: 34512549 PMCID: PMC8428150 DOI: 10.3389/fendo.2021.717544] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/28/2021] [Indexed: 11/20/2022] Open
Abstract
Liver-expressed antimicrobial peptide 2 (LEAP-2), originally described as an antimicrobial peptide, has recently been recognized as an endogenous blocker of growth hormone secretagogue receptor 1a (GHS-R1a). GHS-R1a, also known as ghrelin receptor, is a G protein-coupled receptor (GPCR) widely distributed on the hypothalamus and pituitary gland where it exerts its major functions of regulating appetite and growth hormone (GH) secretion. The activity of GHS-R1a is controlled by two counter-regulatory endogenous ligands: Ghrelin (activation) and LEAP-2 (inhibition). Ghrelin activates GHS-R1a on the neuropeptide Y/Agouti-related protein (NPY/AgRP) neurons at the arcuate nucleus (ARC) to promote appetite, and on the pituitary somatotrophs to stimulate GH release. On the flip side, LEAP-2, acts both as an endogenous competitive antagonist of ghrelin and an inverse agonist of constitutive GHS-R1a activity. Such a biological property of LEAP-2 vigorously blocks ghrelin's effects on food intake and hormonal secretion. In circulation, LEAP-2 displays an inverse pattern as to ghrelin; it increases with food intake and obesity (positive energy balance), whereas decreases upon fasting and weight loss (negative energy balance). Thus, the LEAP-2/ghrelin molar ratio fluctuates in response to energy status and modulation of this ratio conversely influences energy intake. Inhibiting ghrelin's activity has shown beneficial effects on obesity in preclinical experiments, which sheds light on LEAP-2's anti-obesity potential. In this review, we will analyze LEAP-2's effects from a metabolic point of view with a focus on metabolic hormones (e.g., ghrelin, GH, and insulin), and discuss LEAP-2's potential as a promising therapeutic target for obesity.
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Affiliation(s)
- Xuehan Lu
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Lili Huang
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Zhengxiang Huang
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Dandan Feng
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
- Department of Physiology, Xiangya Medical School, Central South University, Changsha, China
| | - Richard J. Clark
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
- *Correspondence: Chen Chen,
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20
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Abstract
Ghrelin, a small peptide hormone (28 aa), secreted mainly by X/A-like cells of gastric mucosa, is also locally produced in cardiomyocytes. Being an orexigenic factor (appetite stimulant), it promotes release of growth hormone (GH) and exerts diverse physiological functions, viz. regulation of energy balance, glucose, and/or fat metabolism for body weight maintenance. Interestingly, administration of exogenous ghrelin significantly improves cardiac functions in CVD patients as well as experimental animal models of heart failure. Ghrelin ameliorates pathophysiological condition of the heart in myocardial infarction, cardiac hypertrophy, fibrosis, cachexia, and ischemia reperfusion injury. This peptide also exerts significant impact at the level of vasculature leading to lowering high blood pressure and reversal of endothelial dysfunction and atherosclerosis. However, the molecular mechanism of actions elucidating the healing effects of ghrelin on the cardiovascular system is still a matter of conjecture. Some experimental data indicate its beneficial effects via complex cellular cross talks between autonomic nervous system and cardiovascular cells, some other suggest more direct receptor-mediated molecular actions via autophagy or ionotropic regulation and interfering with apoptotic and inflammatory pathways of cardiomyocytes and vascular endothelial cells. Here, in this review, we summarise available recent data to encourage more research to find the missing links of unknown ghrelin receptor-mediated pathways as we see ghrelin as a future novel therapy in cardiovascular protection.
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Affiliation(s)
- Shreyasi Gupta
- Department of Zoology, Triveni Devi Bhalotia College, Raniganj, Paschim Bardhaman, 713347, India
| | - Arkadeep Mitra
- Department of Zoology, City College , 102/1, Raja Rammohan Sarani, Kolkata, 700009, India.
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21
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Navarro JA, Decara J, Medina-Vera D, Tovar R, Suarez J, Pavón J, Serrano A, Vida M, Gutierrez-Adan A, Sanjuan C, Baixeras E, de Fonseca FR. D-Pinitol from Ceratonia siliqua Is an Orally Active Natural Inositol That Reduces Pancreas Insulin Secretion and Increases Circulating Ghrelin Levels in Wistar Rats. Nutrients 2020; 12:nu12072030. [PMID: 32650579 PMCID: PMC7400942 DOI: 10.3390/nu12072030] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/03/2020] [Accepted: 07/06/2020] [Indexed: 12/18/2022] Open
Abstract
To characterize the metabolic actions of D-Pinitol, a dietary inositol, in male Wistar rats, we analyzed its oral pharmacokinetics and its effects on (a) the secretion of hormones regulating metabolism (insulin, glucagon, IGF-1, ghrelin, leptin and adiponectin), (b) insulin signaling in the liver and (c) the expression of glycolytic and neoglucogenesis enzymes. Oral D-Pinitol administration (100 or 500 mg/Kg) resulted in its rapid absorption and distribution to plasma and liver compartments. Its administration reduced insulinemia and HOMA-IR, while maintaining glycaemia thanks to increased glucagon activity. In the liver, D-Pinitol reduced the key glycolytic enzyme pyruvate kinase and decreased the phosphorylation of the enzymes AKT and GSK-3. These observations were associated with an increase in ghrelin concentrations, a known inhibitor of insulin secretion. The profile of D-Pinitol suggests its potential use as a pancreatic protector decreasing insulin secretion through ghrelin upregulation, while sustaining glycaemia through the liver-based mechanisms of glycolysis control.
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Affiliation(s)
- Juan A. Navarro
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
- Facultad de Medicina, Universidad de Málaga, 29010 Málaga, Spain
| | - Juan Decara
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
| | - Dina Medina-Vera
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
- Facultad de Ciencias, Universidad de Málaga, 29010 Málaga, Spain
| | - Rubén Tovar
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
- Facultad de Medicina, Universidad de Málaga, 29010 Málaga, Spain
| | - Juan Suarez
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
| | - Javier Pavón
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
| | - Antonia Serrano
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
| | - Margarita Vida
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
| | - Alfonso Gutierrez-Adan
- Departamento de Reproducción Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, 28040 Madrid, Spain;
| | - Carlos Sanjuan
- Euronutra S.L. Calle Johannes Kepler, 3, 29590 Málaga, Spain
- Correspondence: (C.S.); (E.B.); (F.R.d.F.); Tel.: +34-655-373-093 (E.B.); +34-669-426-548 (F.R.d.F.)
| | - Elena Baixeras
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Málaga, 29010 Málaga, Spain
- Correspondence: (C.S.); (E.B.); (F.R.d.F.); Tel.: +34-655-373-093 (E.B.); +34-669-426-548 (F.R.d.F.)
| | - Fernando Rodríguez de Fonseca
- Laboratorio de Medicina Regenerativa, Instituto IBIMA de Málaga, Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, 29010 Málaga, Spain; (J.A.N.); (J.D.); (D.M.-V.); (R.T.); (J.S.); (J.P.); (A.S.); (M.V.)
- Correspondence: (C.S.); (E.B.); (F.R.d.F.); Tel.: +34-655-373-093 (E.B.); +34-669-426-548 (F.R.d.F.)
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22
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Bru-Tari E, Oropeza D, Herrera PL. Cell Heterogeneity and Paracrine Interactions in Human Islet Function: A Perspective Focused in β-Cell Regeneration Strategies. Front Endocrinol (Lausanne) 2020; 11:619150. [PMID: 33613453 PMCID: PMC7888438 DOI: 10.3389/fendo.2020.619150] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/14/2020] [Indexed: 12/27/2022] Open
Abstract
The β-cell regeneration field has shown a strong knowledge boost in the last 10 years. Pluripotent stem cell differentiation and direct reprogramming from other adult cell types are becoming more tangible long-term diabetes therapies. Newly generated β-like-cells consistently show hallmarks of native β-cells and can restore normoglycemia in diabetic mice in virtually all recent studies. Nonetheless, these cells still show important compromises in insulin secretion, cell metabolism, electrical activity, and overall survival, perhaps due to a lack of signal integration from other islet cells. Mounting data suggest that diabetes is not only a β-cell disease, as the other islet cell types also contribute to its physiopathology. Here, we present an update on the most recent studies of islet cell heterogeneity and paracrine interactions in the context of restoring an integrated islet function to improve β-cell replacement therapies.
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