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Maranesi M, Palmioli E, Dall'Aglio C, Marini D, Anipchenko P, De Felice E, Scocco P, Mercati F. Resistin in endocrine pancreas of sheep: Presence and expression related to different diets. Gen Comp Endocrinol 2024; 348:114452. [PMID: 38246291 DOI: 10.1016/j.ygcen.2024.114452] [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: 10/05/2023] [Revised: 12/30/2023] [Accepted: 01/14/2024] [Indexed: 01/23/2024]
Abstract
Resistin (RETN), a recently discovered adipokine, is a cysteine-rich and secretory protein produced by adipocytes. RETN has been detected in several tissues, including human and laboratory animals' pancreas, wherein impairs glucose tolerance and insulin (INS) action and causes INS resistance. This study aims to evaluate the presence and expression of RETN in the pancreas of 15 adult female sheep reared on Apennine pastures, which show a decrease in their nutritional value due to the drought stress linked to the increasing summer aridity. The sheep were divided into 3 groups according to the diet they were subjected to: maximum pasture flowering (MxF) group, maximum pasture dryness (MxD) group, and experimental (Exp) group which received a feed supplementation in addition to the MxD group feeding. Immunohistochemistry and immunofluorescence were performed on formalin-fixed and paraffin-embedded sections of the pancreas to detect the RETN presence and to evaluate the co-localization of RETN with both glucagon (GCG)- and INS-producing cells. In addition, the expression of the three molecules was evaluated also in relation to different diets. RETN was observed only in the endocrine pancreas, showing a wide distribution throughout the pancreatic islets with few negative cells and the RETN producing cells colocalized with both α cells and ß cells. No differences in distribution and immunostaining intensity of RETN, GCG and INS were observed among the three groups. Quantitative PCR showed the expression of RETN, GCG and INS in all tested samples. No significant differences were observed for RETN and GCG among all three groups of sheep. Instead, a high statistically significant expression of INS was detected in the MxF group with respect to the Exp and MxD groups. These results highlight the localization of RETN in GCG- and INS-secreting cells involved in glucose homeostasis suggesting a modulatory role for RETN. Furthermore, the RETN expression is not influenced by food supplementation and thus is not affected by diet.
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Affiliation(s)
- Margherita Maranesi
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, IT, Italy.
| | - Elisa Palmioli
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, IT, Italy; Department of Philosophy, Social Sciences, and Education, PhD Course in "Ethics of Communication, Scientific Research and Technological Innovation" Medical-Health Curriculum, University of Perugia, Piazza G. Ermini, 1, 06123 Perugia, IT, Italy.
| | - Cecilia Dall'Aglio
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, IT, Italy.
| | - Daniele Marini
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, IT, Italy; Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden.
| | - Polina Anipchenko
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, IT, Italy.
| | - Elena De Felice
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Pontoni 5, 62032 Camerino, IT, Italy.
| | - Paola Scocco
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Pontoni 5, 62032 Camerino, IT, Italy.
| | - Francesca Mercati
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, IT, Italy.
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Tatum SM, Holland WL. Germline and conditional ghrelin knockout increases islet size. J Clin Invest 2023; 133:e175799. [PMID: 38099493 PMCID: PMC10721140 DOI: 10.1172/jci175799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023] Open
Abstract
Conflicting studies in recent years report that genetic or pharmacological increases or decreases in ghrelin either increase or have no effect on islet size. In this issue of the JCI, Gupta, Burstein, and colleagues applied a rigorous approach to determine the effects of reducing ghrelin on islet size in germline and conditional ghrelin-knockout mice as well as across varying ages and weight. Both germline and conditional ghrelin-knockout mice associated with increased islet size, which was further exacerbated by older age and diet-induced obesity. These findings suggest that modulation of ghrelin may open a therapeutic window to prevent or treat diabetes.
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Sadria M, Layton A, Bader GD. Adversarial training improves model interpretability in single-cell RNA-seq analysis. BIOINFORMATICS ADVANCES 2023; 3:vbad166. [PMID: 38099262 PMCID: PMC10719216 DOI: 10.1093/bioadv/vbad166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/28/2023] [Accepted: 11/22/2023] [Indexed: 12/17/2023]
Abstract
Motivation Predictive computational models must be accurate, robust, and interpretable to be considered reliable in important areas such as biology and medicine. A sufficiently robust model should not have its output affected significantly by a slight change in the input. Also, these models should be able to explain how a decision is made to support user trust in the results. Efforts have been made to improve the robustness and interpretability of predictive computational models independently; however, the interaction of robustness and interpretability is poorly understood. Results As an example task, we explore the computational prediction of cell type based on single-cell RNA-seq data and show that it can be made more robust by adversarially training a deep learning model. Surprisingly, we find this also leads to improved model interpretability, as measured by identifying genes important for classification using a range of standard interpretability methods. Our results suggest that adversarial training may be generally useful to improve deep learning robustness and interpretability and that it should be evaluated on a range of tasks. Availability and implementation Our Python implementation of all analysis in this publication can be found at: https://github.com/MehrshadSD/robustness-interpretability. The analysis was conducted using numPy 0.2.5, pandas 2.0.3, scanpy 1.9.3, tensorflow 2.10.0, matplotlib 3.7.1, seaborn 0.12.2, sklearn 1.1.1, shap 0.42.0, lime 0.2.0.1, matplotlib_venn 0.11.9.
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Affiliation(s)
- Mehrshad Sadria
- Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Anita Layton
- Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Cheriton School of Computer Science, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- School of Pharmacy, University of Waterloo, Waterloo, Ontario N2G 1C5, Canada
| | - Gary D Bader
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
- The Donnelly Centre, University of Toronto, Toronto, Ontario M5S 3E1, Canada
- Department of Computer Science, University of Toronto, Toronto, Ontario M5S 2E4, Canada
- The Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario M5G 2M9, Canada
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Al-Ani Z, Ko J, Petrov MS. Intra-pancreatic fat deposition across the pancreatitis spectrum and the influence of gut hormones. Dig Liver Dis 2023; 55:1081-1090. [PMID: 36878840 DOI: 10.1016/j.dld.2023.02.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/13/2022] [Accepted: 02/15/2023] [Indexed: 03/08/2023]
Abstract
BACKGROUND AND AIMS Acute pancreatitis (AP) and chronic pancreatitis (CP) often represent parts of the spectrum of disease. While growing evidence indicates that intra-pancreatic fat deposition (IPFD) plays an important role in the pathogenesis of pancreatitis, no study of living individuals has investigated IPFD in both AP and CP. Further, the associations between IPFD and gut hormones remain to be elucidated. The aims were to investigate the associations of IPFD with AP, CP, and health; and to study whether gut hormones affect these associations. METHODS Magnetic resonance imaging on the same 3.0 Tesla scanner was used to determine IPFD in 201 study participants. These participants were arranged into the health, AP, and CP groups. Gut hormones (ghrelin, glucagon-like peptide-1, gastric inhibitory peptide, peptide YY, and oxyntomodulin) were measured in blood, both after an 8-hour overnight fasting and after ingestion of a standardised mixed meal. A series of linear regression analyses was run, accounting for age, sex, ethnicity, body mass index, glycated haemoglobin, and triglycerides. RESULTS Both the AP group and CP group had significantly higher IPFD in comparison with the health group, consistently across all models (p for trend 0.027 in the most adjusted model). Ghrelin in the fasted state had a significant positive association with IPFD in the AP group (but not the CP or health group), consistently across all models (p = 0.019 in the most adjusted model). None of the studied gut hormones in the postprandial state was significantly associated with IPFD. CONCLUSION Fat deposition in the pancreas is similarly high in individuals with AP and those with CP. The gut-brain axis, and more specifically overexpression of ghrelin, may contribute to increased IPFD in individuals with AP.
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Affiliation(s)
- Zena Al-Ani
- School of Medicine, University of Auckland, Auckland, New Zealand
| | - Juyeon Ko
- School of Medicine, University of Auckland, Auckland, New Zealand
| | - Maxim S Petrov
- School of Medicine, University of Auckland, Auckland, New Zealand.
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5
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Infante M, Ricordi C. The unique pathophysiological features of diabetes mellitus secondary to total pancreatectomy: proposal for a new classification distinct from diabetes of the exocrine pancreas. Expert Rev Endocrinol Metab 2023; 18:19-32. [PMID: 36692892 DOI: 10.1080/17446651.2023.2168645] [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: 09/07/2022] [Accepted: 01/11/2023] [Indexed: 01/21/2023]
Abstract
INTRODUCTION Diabetes of the exocrine pancreas (DEP; a.k.a. pancreatic diabetes or pancreatogenic diabetes or type 3c diabetes mellitus or T3cDM) refers to different diabetes types resulting from disorders of the exocrine pancreas. DEP is characterized by the structural and functional loss of glucose-normalizing insulin secretion in the context of exocrine pancreatic dysfunction. Among these forms, new-onset diabetes mellitus secondary to total pancreatectomy (TP) has unique pathophysiological and clinical features, for which we propose a new nomenclature such as post-total pancreatectomy diabetes mellitus (PTPDM). AREAS COVERED TP results in the complete loss of pancreatic parenchyma, with subsequent absolute insulinopenia and lifelong need for exogenous insulin therapy. Patients with PTPDM also exhibit deficiency of glucagon, amylin and pancreatic polypeptide. These endocrine abnormalities, coupled with increased peripheral insulin sensitivity, deficiency of pancreatic enzymes and TP-related modifications of gastrointestinal anatomy, can lead to marked glucose variability and increased risk of iatrogenic (insulin-induced) severe hypoglycemic episodes ('brittle diabetes'). EXPERT OPINION We believe that diabetes mellitus secondary to TP should not be included in the DEP spectrum in light of its peculiar pathophysiological and clinical features. Therefore, we propose a new classification for this entity, that would likely provide more accurate prognosis and treatment strategies.
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Affiliation(s)
- Marco Infante
- Cell Transplant Center, Diabetes Research Institute (DRI), University of Miami Miller School of Medicine, Miami, FL, USA
- Section of Diabetes and Metabolic Disorders, UniCamillus, Saint Camillus International University of Health Sciences, Rome, Italy
- Diabetes Research Institute Federation (DRIF), Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Rome, Italy
| | - Camillo Ricordi
- Cell Transplant Center, Diabetes Research Institute (DRI), University of Miami Miller School of Medicine, Miami, FL, USA
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Importance of multiple endocrine cell types in islet organoids for type 1 diabetes treatment. Transl Res 2022; 250:68-83. [PMID: 35772687 DOI: 10.1016/j.trsl.2022.06.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 06/08/2022] [Accepted: 06/21/2022] [Indexed: 11/21/2022]
Abstract
Almost 50 years ago, scientists developed the bi-hormonal abnormality hypothesis, stating that diabetes is not caused merely by the impaired insulin signaling. Instead, the presence of inappropriate level of glucagon is a prerequisite for the development of type 1 diabetes (T1D). It is widely understood that the hormones insulin and glucagon, secreted by healthy β and α cells respectively, operate in a negative feedback loop to maintain the body's blood sugar levels. Despite this fact, traditional T1D treatments rely solely on exogenous insulin injections. Furthermore, research on cell-based therapies and stem-cell derived tissues tends to focus on the replacement of β cells alone. In vivo, the pancreas is made up of 4 major endocrine cell types, that is, insulin-producing β cells, glucagon-producing α cells, somatostatin-producing δ cells, and pancreatic polypeptide-producing γ cells. These distinct cell types are involved synergistically in regulating islet functions. Therefore, it is necessary to produce a pancreatic islet organoid in vitro consisting of all these cell types that adequately replaces the function of the native islets. In this review, we describe the unique function of each pancreatic endocrine cell type and their interactions contributing to the maintenance of normoglycemia. Furthermore, we detail current sources of whole islets and techniques for their long-term expansion and culture. In addition, we highlight a vast potential of the pancreatic islet organoids for transplantation and diabetes research along with updated new approaches for successful transplantation using stem cell-derived islet organoids.
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7
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Lubberding AF, Juhl CR, Skovhøj EZ, Kanters JK, Mandrup‐Poulsen T, Torekov SS. Celebrities in the heart, strangers in the pancreatic beta cell: Voltage-gated potassium channels K v 7.1 and K v 11.1 bridge long QT syndrome with hyperinsulinaemia as well as type 2 diabetes. Acta Physiol (Oxf) 2022; 234:e13781. [PMID: 34990074 PMCID: PMC9286829 DOI: 10.1111/apha.13781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 12/20/2021] [Accepted: 01/02/2022] [Indexed: 12/13/2022]
Abstract
Voltage‐gated potassium (Kv) channels play an important role in the repolarization of a variety of excitable tissues, including in the cardiomyocyte and the pancreatic beta cell. Recently, individuals carrying loss‐of‐function (LoF) mutations in KCNQ1, encoding Kv7.1, and KCNH2 (hERG), encoding Kv11.1, were found to exhibit post‐prandial hyperinsulinaemia and episodes of hypoglycaemia. These LoF mutations also cause the cardiac disorder long QT syndrome (LQTS), which can be aggravated by hypoglycaemia. Interestingly, patients with LQTS also have a higher burden of diabetes compared to the background population, an apparent paradox in relation to the hyperinsulinaemic phenotype, and KCNQ1 has been identified as a type 2 diabetes risk gene. This review article summarizes the involvement of delayed rectifier K+ channels in pancreatic beta cell function, with emphasis on Kv7.1 and Kv11.1, using the cardiomyocyte for context. The functional and clinical consequences of LoF mutations and polymorphisms in these channels on blood glucose homeostasis are explored using evidence from pre‐clinical, clinical and genome‐wide association studies, thereby evaluating the link between LQTS, hyperinsulinaemia and type 2 diabetes.
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Affiliation(s)
- Anniek F. Lubberding
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Christian R. Juhl
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Emil Z. Skovhøj
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Jørgen K. Kanters
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Thomas Mandrup‐Poulsen
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Signe S. Torekov
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
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8
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Pablos M, Casanueva-Álvarez E, González-Casimiro CM, Merino B, Perdomo G, Cózar-Castellano I. Primary Cilia in Pancreatic β- and α-Cells: Time to Revisit the Role of Insulin-Degrading Enzyme. Front Endocrinol (Lausanne) 2022; 13:922825. [PMID: 35832432 PMCID: PMC9271624 DOI: 10.3389/fendo.2022.922825] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 05/24/2022] [Indexed: 12/25/2022] Open
Abstract
The primary cilium is a narrow organelle located at the surface of the cell in contact with the extracellular environment. Once underappreciated, now is thought to efficiently sense external environmental cues and mediate cell-to-cell communication, because many receptors, ion channels, and signaling molecules are highly or differentially expressed in primary cilium. Rare genetic disorders that affect cilia integrity and function, such as Bardet-Biedl syndrome and Alström syndrome, have awoken interest in studying the biology of cilium. In this review, we discuss recent evidence suggesting emerging roles of primary cilium and cilia-mediated signaling pathways in the regulation of pancreatic β- and α-cell functions, and its implications in regulating glucose homeostasis.
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Affiliation(s)
- Marta Pablos
- Department of Biochemistry, Molecular Biology and Physiology, School of Medicine, University of Valladolid, Valladolid, Spain
- *Correspondence: Marta Pablos,
| | - Elena Casanueva-Álvarez
- Unidad de Excelencia Instituto de Biología y Genética Molecular, University of Valladolid Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Carlos M. González-Casimiro
- Unidad de Excelencia Instituto de Biología y Genética Molecular, University of Valladolid Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Beatriz Merino
- Unidad de Excelencia Instituto de Biología y Genética Molecular, University of Valladolid Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Germán Perdomo
- Unidad de Excelencia Instituto de Biología y Genética Molecular, University of Valladolid Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Irene Cózar-Castellano
- Department of Biochemistry, Molecular Biology and Physiology, School of Medicine, University of Valladolid, Valladolid, Spain
- Unidad de Excelencia Instituto de Biología y Genética Molecular, University of Valladolid Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
- Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
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9
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Chinen K, Sakata N, Yoshimatsu G, Nakamura M, Kodama S. Therapeutic effects of acylated ghrelin-specific receptor GHS-R1a antagonist in islet transplantation. Sci Rep 2021; 11:21239. [PMID: 34711885 PMCID: PMC8553779 DOI: 10.1038/s41598-021-00740-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 10/07/2021] [Indexed: 11/10/2022] Open
Abstract
Islet transplantation is a type of cellular replacement therapy for severe diabetes that is limited by compromising effect on engrafted islets. Trials aiming to improve the function of transplanted islets have also been challenging. This study attempted to elucidate whether regulation of growth hormone secretagogue receptor-1a (GHS-R1a), one of the ghrelin receptors, improve the therapeutic effects of islet transplantation using [D-Lys3]-GHRP-6 (DLS), a specific GHS-R1a antagonist. The therapeutic effects of DLS were assessed in terms of the expression/production of endocrine genes/proteins, insulin-releasing function under glucose stimulation of mouse islets, and outcomes of syngeneic murine islet transplantation with systemic DLS administration. DLS treatment promoted insulin production and suppressed somatostatin production, suggesting that cancelation of the binding between ghrelin and GHS-R1a on β or δ cells improved insulin expression. DLS also promoted the glucose-dependent insulin-releasing function of β cells. However, the therapeutic effect of DLS in islet transplantation was fractional. In conclusion, the GHS-R1a antagonist showed preferable effects in improving the therapeutic outcomes of islet transplantation, including the promotion of insulin-releasing function.
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Affiliation(s)
- Kiyoshi Chinen
- Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan.,Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, 812-8582, Japan
| | - Naoaki Sakata
- Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan.
| | - Gumpei Yoshimatsu
- Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan
| | - Masafumi Nakamura
- Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, 812-8582, Japan
| | - Shohta Kodama
- Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan
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10
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Smitka K, Prochazkova P, Roubalova R, Dvorak J, Papezova H, Hill M, Pokorny J, Kittnar O, Bilej M, Tlaskalova-Hogenova H. Current Aspects of the Role of Autoantibodies Directed Against Appetite-Regulating Hormones and the Gut Microbiome in Eating Disorders. Front Endocrinol (Lausanne) 2021; 12:613983. [PMID: 33953692 PMCID: PMC8092392 DOI: 10.3389/fendo.2021.613983] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 03/09/2021] [Indexed: 12/12/2022] Open
Abstract
The equilibrium and reciprocal actions among appetite-stimulating (orexigenic) and appetite-suppressing (anorexigenic) signals synthesized in the gut, brain, microbiome and adipose tissue (AT), seems to play a pivotal role in the regulation of food intake and feeding behavior, anxiety, and depression. A dysregulation of mechanisms controlling the energy balance may result in eating disorders such as anorexia nervosa (AN) and bulimia nervosa (BN). AN is a psychiatric disease defined by chronic self-induced extreme dietary restriction leading to an extremely low body weight and adiposity. BN is defined as out-of-control binge eating, which is compensated by self-induced vomiting, fasting, or excessive exercise. Certain gut microbiota-related compounds, like bacterial chaperone protein Escherichia coli caseinolytic protease B (ClpB) and food-derived antigens were recently described to trigger the production of autoantibodies cross-reacting with appetite-regulating hormones and neurotransmitters. Gut microbiome may be a potential manipulator for AT and energy homeostasis. Thus, the regulation of appetite, emotion, mood, and nutritional status is also under the control of neuroimmunoendocrine mechanisms by secretion of autoantibodies directed against neuropeptides, neuroactive metabolites, and peptides. In AN and BN, altered cholinergic, dopaminergic, adrenergic, and serotonergic relays may lead to abnormal AT, gut, and brain hormone secretion. The present review summarizes updated knowledge regarding the gut dysbiosis, gut-barrier permeability, short-chain fatty acids (SCFA), fecal microbial transplantation (FMT), blood-brain barrier permeability, and autoantibodies within the ghrelin and melanocortin systems in eating disorders. We expect that the new knowledge may be used for the development of a novel preventive and therapeutic approach for treatment of AN and BN.
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Affiliation(s)
- Kvido Smitka
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
- First Faculty of Medicine, Institute of Pathological Physiology, Charles University, Prague, Czechia
- *Correspondence: Kvido Smitka,
| | - Petra Prochazkova
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Radka Roubalova
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Jiri Dvorak
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Hana Papezova
- Psychiatric Clinic, Eating Disorder Center, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Martin Hill
- Steroid Hormone and Proteofactors Department, Institute of Endocrinology, Prague, Czechia
| | - Jaroslav Pokorny
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
| | - Otomar Kittnar
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
| | - Martin Bilej
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Helena Tlaskalova-Hogenova
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
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11
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Wei Q, Qi L, Lin H, Liu D, Zhu X, Dai Y, Waldron RT, Lugea A, Goodarzi MO, Pandol SJ, Li L. Pathological Mechanisms in Diabetes of the Exocrine Pancreas: What's Known and What's to Know. Front Physiol 2020; 11:570276. [PMID: 33250773 PMCID: PMC7673428 DOI: 10.3389/fphys.2020.570276] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 10/07/2020] [Indexed: 12/17/2022] Open
Abstract
The clinical significance of diabetes arising in the setting of pancreatic disease (also known as diabetes of the exocrine pancreas, DEP) has drawn more attention in recent years. However, significant improvements still need to be made in the recognition, diagnosis and treatment of the disorder, and in the knowledge of the pathological mechanisms. The clinical course of DEP is different from type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). DEP develops in patients with previous existing exocrine pancreatic disorders which damage both exocrine and endocrine parts of pancreas, and lead to pancreas exocrine insufficiency (PEI) and malnutrition. Therefore, damage in various exocrine and endocrine cell types participating in glucose metabolism regulation likely contribute to the development of DEP. Due to the limited amount of clinical and experimental studies, the pathological mechanism of DEP is poorly defined. In fact, it still not entirely clear whether DEP represents a distinct pathologic entity or is a form of T2DM arising when β cell failure is accelerated by pancreatic disease. In this review, we include findings from related studies in T1DM and T2DM to highlight potential pathological mechanisms involved in initiation and progression of DEP, and to provide directions for future research studies.
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Affiliation(s)
- Qiong Wei
- Department of Endocrinology, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China.,Institute of Pancreas, Southeast University, Nanjing, China
| | - Liang Qi
- Department of Endocrinology, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Hao Lin
- Institute of Pancreas, Southeast University, Nanjing, China.,Department of Clinical Science and Research, ZhongDa Hospital, Southeast University, Nanjing, China
| | - Dechen Liu
- Institute of Pancreas, Southeast University, Nanjing, China.,Department of Clinical Science and Research, ZhongDa Hospital, Southeast University, Nanjing, China
| | - Xiangyun Zhu
- Department of Endocrinology, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China.,Institute of Pancreas, Southeast University, Nanjing, China
| | - Yu Dai
- Nanjing Foreign Language School, Nanjing, China
| | - Richard T Waldron
- Division of Gastroenterology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Aurelia Lugea
- Division of Gastroenterology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Mark O Goodarzi
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Stephen J Pandol
- Division of Gastroenterology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Ling Li
- Department of Endocrinology, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China.,Institute of Pancreas, Southeast University, Nanjing, China
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12
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Cheng JT, Wang YY, Zhu LZ, Zhang Y, Cai WQ, Han ZW, Zhou Y, Wang XW, Peng XC, Xiang Y, Yang HY, Cui SZ, Ma Z, Liu BR, Xin HW. Novel transcription regulatory sequences and factors of the immune evasion protein ICP47 (US12) of herpes simplex viruses. Virol J 2020; 17:101. [PMID: 32650799 PMCID: PMC7377220 DOI: 10.1186/s12985-020-01365-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 06/23/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Herpes simplex virus (HSV) can cause encephalitis. Its infected cell polypeptide 47 (ICP47), encoded by immediate-early gene US12, promotes immune escape. ICP47 was modified in the clinically approved oncolytic HSV (oHSV) T-Vec. However, transcription regulatory sequence (TRS) and transcription regulatory factor (TRF) of HSV US12 are seldom reported. METHODS Previously, our laboratory isolated a new HSV strain named HSV-1-LXMW from a male patient with oral herpes in Beijing, China. Firstly, the genetic tree was used to analyze its genetic relationship. The US12 TRS and TRF in HSV-1-LXMW were found by using predictive software. Secondly, the further verification by the multi-sequence comparative analysis shown that the upstream DNA sequence of HSV US12 gene contained the conserved region. Finally, the results of literature search shown that the expression of transcription factors was related to the tissue affinity of HSV-1 and HSV-2, so as to increase the new understanding of the transcriptional regulation of HSV biology and oncolytic virus (OVs) therapy. RESULTS Here we reported the transcriptional regulation region sequence of our new HSV-1-LXMW, and its close relationship with HSV-1-CR38 and HSV-1-17. Importantly we identified eight different kinds of novel TRSs and TRFs of HSV US12 for the first time, and found they are conserved among HSV-1 (c-Rel, Elk-1, Pax-4), HSV-2 (Oct-1, CF2-II, E74A, StuAp) or both HSVs (HNF-4). The TRFs c-Rel and Oct-1 are biologically functional respectively in immune escape and viral replication during HSV infection. CONCLUSIONS Our findings have important implication to HSV biology, infection, immunity and oHSVs.
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Affiliation(s)
- Jun-Ting Cheng
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Ying-Ying Wang
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Lin-Zhong Zhu
- Department of Interventional Therapy, Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute. 52, Fucheng Road, Haidian District, Beijing, 100142, China
| | - Ying Zhang
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Wen-Qi Cai
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Zi-Wen Han
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Yang Zhou
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Xian-Wang Wang
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Laboratory Medicine, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China
| | - Xiao-Chun Peng
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Pathophysiology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Ying Xiang
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China.,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China
| | - Hui-Yu Yang
- Department of Gastroenterology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Shu-Zhong Cui
- State Key Laboratory of Respiratory Disease, Affiliated Cancer Hospital Institute of Guangzhou Medical University, Guangzhou, 510095, China
| | - Zhaowu Ma
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China. .,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China.
| | - Bing-Rong Liu
- Department of Gastroenterology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
| | - Hong-Wu Xin
- Laboratory of Oncology, School of Basic Medicine, Health Science Center, Yangtze University, 1 Nanhuan Road, Jingzhou, 434023, Hubei, China. .,Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, Hubei, China. .,Lianjiang People's Hospital, Guangdong, 524400, China.
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13
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Exogenous Ghrelin Increases Plasma Insulin Level in Diabetic Rats. Biomolecules 2020; 10:biom10040633. [PMID: 32325912 PMCID: PMC7226305 DOI: 10.3390/biom10040633] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/09/2020] [Accepted: 04/15/2020] [Indexed: 12/13/2022] Open
Abstract
Ghrelin, a 28-amino acid peptide, is a strong growth hormone secretagogue and a regulator of food intake. In addition, ghrelin is thought to play a role in insulin secretion and in glucose homeostasis. A lot of contradictory data have been reported in the literature regarding the co-localization of ghrelin with other hormones in the islet of Langerhans, its role in insulin secretion and attenuation of type 2 diabetes mellitus. In this study, we investigate the effect of chronic ghrelin treatment on glucose, body weight and insulin level in normal and streptozotocin-induced diabetic male Wistar rats. We have also examined the distribution pattern and co-localization of ghrelin with insulin in pancreatic islet cells using immunohistochemistry and immune-electron microscopy and the ability of ghrelin to stimulate insulin release from the CRL11065 beta cell line. Control, non-diabetic groups received intraperitoneal injection of normal saline, while treated groups received intraperitoneal injection of 5 µg/kg body weight of ghrelin (amino acid chain 24–51) on a daily basis for a duration of four weeks. Our results show that the administration of ghrelin increases the number of insulin-secreting beta cells and serum insulin level in both normal and diabetic rats. We also demonstrated that ghrelin co-localizes with insulin in pancreatic islet cells and that the pattern of ghrelin distribution is altered after the onset of diabetes. Moreover, ghrelin at a dose of 10−6 M and 10−12 M increased insulin release from the CRL11065 beta cell line. In summary, ghrelin co-localizes with insulin in the secretory granules of pancreatic beta cells and enhances insulin production.
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14
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Chang R, Qin H, Liang Z, Qin M, Wang H, Wei Y, Fu H, Huang H, Tang G. An improved method for the isolation and culture of rat pancreatic ductal epithelial cells. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:320. [PMID: 32355764 PMCID: PMC7186642 DOI: 10.21037/atm.2020.03.75] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background This aim of this study was to explore a novel method that can be used to isolate and culture rat pancreatic ductal epithelial cells. Methods Retrograde injection of indigo carmine solution into the bile duct of rats revealed the main pancreatic duct, which was isolated using the naked eye (without using a stereomicroscope). The main pancreatic duct was sequentially digested with three enzymes, and the digested cells were cultured in RPMI-1640 medium containing 10–15% fetal bovine serum. After 72 h, the primary pancreatic ductal epithelial cells started to adhere to the wall. The cells reached 70–80% confluence after approximately 7 days and were subsequently digested with 0.25% trypsin and subcultured. Cells of the second and fourth passages were harvested. Cytokeratin (CK)-7 and CK-19 protein expressions in the cells and pancreatic tissue were detected by Western blot analysis. q-PCR was employed to examine CK-7, CK-19, somatostatin, amylase, insulin, and glucagon mRNA expression in the cells and pancreatic tissue after the main pancreatic duct was removed. Results The rats had one or two main pancreatic ducts meeting the bile ducts at a right or an acute angle. Rat pancreatic ductal epithelial cells isolated by this method grew well and showed a cobblestone-like appearance via microscopy. Western blot analysis showed that both the second and fourth passages of pancreatic ductal epithelial cells expressed CK-7 and CK-19 protein. The q-PCR results showed the expression of CK-7 and CK-19 genes in the second and fourth passages of pancreatic ductal epithelial cells, while the somatostatin, amylase, insulin, and glucagon genes were not expressed. The pancreatic tissue harvested after the removal of the main pancreatic duct did not express CK-7 or CK-19, while the somatostatin, amylase, insulin, and glucagon genes were expressed. Conclusions The preliminary results show that this method can be applied to successfully isolate and culture rat pancreatic ductal epithelial cells.
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Affiliation(s)
- Renjie Chang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Heping Qin
- Department of Gastroenterology, Liuzhou People's Hospital, Liuzhou 545006, China
| | - Zhihai Liang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Mengbin Qin
- Department of Gastroenterology, Second Affiliated Hospital of Guangxi Medical University, Nanning 530007, China
| | - Huilin Wang
- Department of Chemotherapy, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - Yule Wei
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Hongzong Fu
- Guangxi International Zhuang Medical Hospital, Nanning 530001, China
| | - Huali Huang
- Department of Gastroenterology of The First People's Hospital of Nanning City, Nanning 530022, China
| | - Guodu Tang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
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15
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Camacho-Ramírez A, Mayo-Ossorio MÁ, Pacheco-García JM, Almorza-Gomar D, Ribelles-García A, Belmonte-Núñez A, Prada-Oliveira JA, Pérez-Arana GM. Pancreas is a preeminent source of ghrelin after sleeve gastrectomy in Wistar rats. Histol Histopathol 2020; 35:801-809. [PMID: 31951010 DOI: 10.14670/hh-18-200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Many surgical techniques are employed in the treatment of severe obesity. A main consequence of these techniques is the improvement of type 2 Diabetes mellitus. Ghrelin is a gut hormone released in the gastric fundus and corpus, which has been related to diabetic improvement as mentioned in these papers. Sleeve gastrectomy and Roux-en Y Gastric Bypass are surgical techniques broadly employed in humans; both severely reduce the gastric surface. Paradoxically, the serum level of ghrelin in patients is preserved. We hypothesized about the role of embryonic pancreatic epsilon cells, which have the capacity to release ghrelin. We studied the changes in the epsilon cells and differentiation markers with immunostaining and ghrelin serum level and after surgery. We employed euglycemic male Wistar rats: two surgical groups (Sleeve gastrectomy and Roux-en Y Gastric Bypass) and two control groups. We reported a significant increase of ghrelin epsilon-cells in the pancreas and basal serum after Sleeve gastrectomy versus the control groups. The epsilon cellular increment was related to neogenesis, as the neurogenin-3 marker revealed. The Roux-en Y Gastric Bypass showed neither epsilon cell increase nor basal serum changes in ghrelin release. As a conclusion, we reported that the severe suppression of the fundus gastric produced the recovery of ghrelin released by the epsilon cells, which was indicative of an ontogenic embryonic pancreatic function.
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Affiliation(s)
- Alonso Camacho-Ramírez
- Surgery Unit, Puerta del Mar University Hospital, University of Cádiz, Cádiz, Spain.,Biomedical Science Research and Innovation Institute (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain.,Asociación Gaditana de Apoyo al Investigador AGAI, Cádiz, Spain
| | - María Ángeles Mayo-Ossorio
- Surgery Unit, Puerta del Mar University Hospital, University of Cádiz, Cádiz, Spain.,Biomedical Science Research and Innovation Institute (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
| | - José Manuel Pacheco-García
- Surgery Unit, Puerta del Mar University Hospital, University of Cádiz, Cádiz, Spain.,Biomedical Science Research and Innovation Institute (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
| | - David Almorza-Gomar
- Biomedical Science Research and Innovation Institute (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain.,Department of Operative Statistic and Research, University of Cádiz, Cádiz, Spain
| | - Antonio Ribelles-García
- Department of Human Anatomy and Embryology, Faculty of Medicine, University of Cádiz, Cádiz, Spain.,Sustainable Social Development Research Institute (INDESS), University of Cádiz, Cádiz, Spain
| | - Ana Belmonte-Núñez
- Department of Human Anatomy and Embryology, Faculty of Medicine, University of Cádiz, Cádiz, Spain
| | - J Arturo Prada-Oliveira
- Biomedical Science Research and Innovation Institute (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain.,Asociación Gaditana de Apoyo al Investigador AGAI, Cádiz, Spain.,Department of Human Anatomy and Embryology, Faculty of Medicine, University of Cádiz, Cádiz, Spain.
| | - Gonzalo M Pérez-Arana
- Biomedical Science Research and Innovation Institute (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain.,Department of Human Anatomy and Embryology, Faculty of Medicine, University of Cádiz, Cádiz, Spain.,Asociación Gaditana de Apoyo al Investigador AGAI, Cádiz, Spain
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16
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Expression of Adenosine Receptors in Rodent Pancreas. Int J Mol Sci 2019; 20:ijms20215329. [PMID: 31717704 PMCID: PMC6862154 DOI: 10.3390/ijms20215329] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/18/2019] [Accepted: 10/24/2019] [Indexed: 02/07/2023] Open
Abstract
Adenosine regulates exocrine and endocrine secretions in the pancreas. Adenosine is considered to play a role in acini-to-duct signaling in the exocrine pancreas. To identify the molecular basis of functional adenosine receptors in the exocrine pancreas, immunohistochemical analysis was performed in the rat, mouse, and guinea pig pancreas, and the secretory rate and concentration of HCO3− in pancreatic juice from the rat pancreas were measured. The A2A adenosine receptor colocalized with ezrin, an A-kinase anchoring protein, in the luminal membrane of duct cells in the mouse and guinea pig pancreas. However, a strong signal ascribed to A2B adenosine receptors was detected in insulin-positive β cells in islets of Langerhans. The A2A adenosine receptor agonist 4-[2-[[6-Amino-9-(N-ethyl-β-D-ribofuranuronamidosyl)-9H-purin-2-yl]amino]ethyl]benzenepropanoic acid (CGS 21680) stimulated HCO3−-rich fluid secretion from the rat pancreas. These results indicate that A2A adenosine receptors may be, at least in part, involved in the exocrine secretion of pancreatic duct cells via acini-to-duct signaling. The adenosine receptors may be a potential therapeutic target for cancer as well as exocrine dysfunctions of the pancreas.
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