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Skelin Klemen M, Dolenšek J, Križančić Bombek L, Pohorec V, Gosak M, Slak Rupnik M, Stožer A. The effect of forskolin and the role of Epac2A during activation, activity, and deactivation of beta cell networks. Front Endocrinol (Lausanne) 2023; 14:1225486. [PMID: 37701894 PMCID: PMC10494243 DOI: 10.3389/fendo.2023.1225486] [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: 05/19/2023] [Accepted: 08/08/2023] [Indexed: 09/14/2023] Open
Abstract
Beta cells couple stimulation by glucose with insulin secretion and impairments in this coupling play a central role in diabetes mellitus. Cyclic adenosine monophosphate (cAMP) amplifies stimulus-secretion coupling via protein kinase A and guanine nucleotide exchange protein 2 (Epac2A). With the present research, we aimed to clarify the influence of cAMP-elevating diterpene forskolin on cytoplasmic calcium dynamics and intercellular network activity, which are two of the crucial elements of normal beta cell stimulus-secretion coupling, and the role of Epac2A under normal and stimulated conditions. To this end, we performed functional multicellular calcium imaging of beta cells in mouse pancreas tissue slices after stimulation with glucose and forskolin in wild-type and Epac2A knock-out mice. Forskolin evoked calcium signals in otherwise substimulatory glucose and beta cells from Epac2A knock-out mice displayed a faster activation. During the plateau phase, beta cells from Epac2A knock-out mice displayed a slightly higher active time in response to glucose compared with wild-type littermates, and stimulation with forskolin increased the active time via an increase in oscillation frequency and a decrease in oscillation duration in both Epac2A knock-out and wild-type mice. Functional network properties during stimulation with glucose did not differ in Epac2A knock-out mice, but the presence of Epac2A was crucial for the protective effect of stimulation with forskolin in preventing a decline in beta cell functional connectivity with time. Finally, stimulation with forskolin prolonged beta cell activity during deactivation, especially in Epac2A knock-out mice.
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Affiliation(s)
- Maša Skelin Klemen
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Jurij Dolenšek
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
- Faculty of Natural Sciences and Mathematics, University of Maribor, Maribor, Slovenia
| | | | - Viljem Pohorec
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Marko Gosak
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
- Faculty of Natural Sciences and Mathematics, University of Maribor, Maribor, Slovenia
- Alma Mater Europaea, European Center Maribor, Maribor, Slovenia
| | - Marjan Slak Rupnik
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
- Alma Mater Europaea, European Center Maribor, Maribor, Slovenia
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Andraž Stožer
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
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Xu F, Xu B, Chen H, Ju X, Gonzalez de Mejia E. Enhancement of DPP-IV inhibitory activity and the capacity for enabling GLP-1 secretion through RADA16-assisted molecular designed rapeseed peptide nanogels. Food Funct 2022; 13:5215-5228. [PMID: 35438092 DOI: 10.1039/d1fo04367f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The potential of pentapeptide IPQVS (RAP1) and octapeptide ELHQEEPL (RAP2) derived from rapeseed napin as natural dipeptidyl-peptidase IV (DPP-IV) inhibitors is promising. The objective was to develop a nanogel strategy to resist the hydrolysis of digestive and intestinal enzymes to enhance the DPP-IV inhibitory activity of RAP1 and RAP2, and stimulate glucagon-like peptide 1 (GLP-1) secretion of RAP2 by a RADA16-assisted molecular design. The linker of double Gly was used in the connection of RADA16 and the functional oligopeptide region (RAP1 and RAP2). Compared to the original oligopeptides, DPP-IV IC50 of the nanogels RADA16-RAP1 and RADA16-RAP2 decreased by 26.43% and 17.46% in Caco-2 cell monolayers, respectively. The results showed that the two nanogel peptides with no toxicity to cells had higher contents of stable β-sheet structures (increased by 5.6-fold and 5.2-fold, respectively) than the original oligopeptides, and a self-assembled fibrous morphology. Rheological results suggested that the nanogels RADA16-RAP1 and RADA16-RAP2 exhibit good rheological properties for potential injectable applications; the storage modulus (G') was 10 times higher than the low modulus (G''). Furthermore, the RAP2 and its RADA16-assisted nanogel peptide at the concentration of 250 μM significantly (P < 0.05) increased the release of GLP-1 by 35.46% through the calcium-sensing receptor pathway in the enteroendocrine STC-1 cells. Hence, the innovative and harmless nanogels with the sequence of RADA16-GG-Xn have the potential for use by oral and injection administration for treating or relieving type 2 diabetes.
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Affiliation(s)
- Feiran Xu
- Engineering Research Center of Bio-process, Ministry of Education, School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, People's Republic of China.,Department of Food Science and Human Nutrition, Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, 228 Edward R. Madigan Laboratory (ERML), 1201 West Gregory Drive, Urbana, Illinois 61801, USA.
| | - Baocai Xu
- Engineering Research Center of Bio-process, Ministry of Education, School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, People's Republic of China
| | - Hong Chen
- Department of Food Science and Human Nutrition, Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, 228 Edward R. Madigan Laboratory (ERML), 1201 West Gregory Drive, Urbana, Illinois 61801, USA.
| | - Xingrong Ju
- National Engineering Laboratory for Cereal Fermentation Technology, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Elvira Gonzalez de Mejia
- Department of Food Science and Human Nutrition, Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, 228 Edward R. Madigan Laboratory (ERML), 1201 West Gregory Drive, Urbana, Illinois 61801, USA.
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Shu Z, Liu W, Wu H, Xiao M, Wu D, Cao T, Ren M, Tao J, Zhang C, He T, Li X, Zhang R, Zhou X. Symptom-based network classification identifies distinct clinical subgroups of liver diseases with common molecular pathways. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2019; 174:41-50. [PMID: 29502851 DOI: 10.1016/j.cmpb.2018.02.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 02/22/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND OBJECTIVE Liver disease is a multifactorial complex disease with high global prevalence and poor long-term clinical efficacy and liver disease patients with different comorbidities often incorporate multiple phenotypes in the clinic. Thus, there is a pressing need to improve understanding of the complexity of clinical liver population to help gain more accurate disease subtypes for personalized treatment. METHODS Individualized treatment of the traditional Chinese medicine (TCM) provides a theoretical basis to the study of personalized classification of complex diseases. Utilizing the TCM clinical electronic medical records (EMRs) of 6475 liver inpatient cases, we built a liver disease comorbidity network (LDCN) to show the complicated associations between liver diseases and their comorbidities, and then constructed a patient similarity network with shared symptoms (PSN). Finally, we identified liver patient subgroups using community detection methods and performed enrichment analyses to find both distinct clinical and molecular characteristics (with the phenotype-genotype associations and interactome networks) of these patient subgroups. RESULTS From the comorbidity network, we found that clinical liver patients have a wide range of disease comorbidities, in which the basic liver diseases (e.g. hepatitis b, decompensated liver cirrhosis), and the common chronic diseases (e.g. hypertension, type 2 diabetes), have high degree of disease comorbidities. In addition, we identified 303 patient modules (representing the liver patient subgroups) from the PSN, in which the top 6 modules with large number of cases include 51.68% of the whole cases and 251 modules contain only 10 or fewer cases, which indicates the manifestation diversity of liver diseases. Finally, we found that the patient subgroups actually have distinct symptom phenotypes, disease comorbidity characteristics and their underlying molecular pathways, which could be used for understanding the novel disease subtypes of liver conditions. For example, three patient subgroups, namely Module 6 (M6, n = 638), M2 (n = 623) and M1 (n = 488) were associated to common chronic liver disease conditions (hepatitis, cirrhosis, hepatocellular carcinoma). Meanwhile, patient subgroups of M30 (n = 36) and M36 (n = 37) were mostly related to acute gastroenteritis and upper respiratory infection, respectively, which reflected the individual comorbidity characteristics of liver subgroups. Furthermore, we identified the distinct genes and pathways of patient subgroups and the basic liver diseases (hepatitis b and cirrhosis), respectively. The high degree of overlapping pathways between them (e.g. M36 with 93.33% shared enriched pathways) indicates the underlying molecular network mechanisms of each patient subgroup. CONCLUSIONS Our results demonstrate the utility and comprehensiveness of disease classification study based on community detection of patient network using shared TCM symptom phenotypes and it can be used to other more complex diseases.
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Affiliation(s)
- Zixin Shu
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; The clinical medical college of Traditional Chinese Medicine, Hubei University of Traditional Chinese Medicine, Wuhan 430065, China
| | - Wenwen Liu
- School of Computer and Information Technology and Beijing Key Lab of Traffic Data Analysis and Mining, Beijing Jiaotong University, Beijing 100044, China
| | - Huikun Wu
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Mingzhong Xiao
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Deng Wu
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Ting Cao
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Meng Ren
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Junxiu Tao
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Chuhua Zhang
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Tangqing He
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China
| | - Xiaodong Li
- Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan 430061, China; Hubei Province Academy of Traditional Chinese Medicine, Wuhan 430061, China.
| | - Runshun Zhang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China.
| | - Xuezhong Zhou
- School of Computer and Information Technology and Beijing Key Lab of Traffic Data Analysis and Mining, Beijing Jiaotong University, Beijing 100044, China.
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Seshadri N, Jonasson ME, Hunt KL, Xiang B, Cooper S, Wheeler MB, Dolinsky VW, Doucette CA. Uncoupling protein 2 regulates daily rhythms of insulin secretion capacity in MIN6 cells and isolated islets from male mice. Mol Metab 2017; 6:760-769. [PMID: 28702331 PMCID: PMC5485245 DOI: 10.1016/j.molmet.2017.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/16/2017] [Accepted: 04/24/2017] [Indexed: 12/17/2022] Open
Abstract
Objective Upregulation of uncoupling protein 2 (UCP2) is associated with impaired glucose-stimulated insulin secretion (GSIS), which is thought to be an important contributor to pathological β cell failure in obesity and type 2 diabetes (T2D); however, the physiological function of UCP2 in the β cell remains undefined. It has been suggested, but not yet tested, that UCP2 plays a physiological role in β cells by coordinating insulin secretion capacity with anticipated fluctuating nutrient supply, such that upregulation of UCP2 in the inactive/fasted state inhibits GSIS as a mechanism to prevent hypoglycemia. Therefore, we hypothesized that daily cycles of GSIS capacity are dependent on rhythmic and predictable patterns of Ucp2 gene expression such that low Ucp2 in the active/fed phase promotes maximal GSIS capacity, whereas elevated Ucp2 expression in the inactive/fasted phase supresses GSIS capacity. We further hypothesized that rhythmic Ucp2 expression is required for the maintenance of glucose tolerance over the 24 h cycle. Methods We used synchronized MIN6 clonal β cells and isolated mouse islets from wild type (C57BL6) and mice with β cell knockout of Ucp2 (Ucp2-βKO; and respective Ins2-cre controls) to determine the endogenous expression pattern of Ucp2 over 24 h and its impact on GSIS capacity and glucose tolerance over 24 h. Results A dynamic pattern of Ucp2 mRNA expression was observed in synchronized MIN6 cells, which showed a reciprocal relationship with GSIS capacity in a time-of-day-specific manner. GSIS capacity was suppressed in islets isolated from wild type and control mice during the light/inactive phase of the daily cycle; a suppression that was dependent on Ucp2 in the β cell and was lost in islets isolated from Ucp2-βKO mice or wild type islets treated with a UCP2 inhibitor. Finally, suppression of GSIS capacity by UCP2 in the light phase was required for the maintenance of normal patterns of glucose tolerance. Conclusions Our study suggests that Ucp2/UCP2 in the β cell is part of an important, endogenous, metabolic regulator that controls the temporal capacity of GSIS over the course of the day/night cycle, which, in turn, regulates time-of-day glucose tolerance. Targeting Ucp2/UCP2 as a therapeutic in type 2 diabetes or any other metabolic condition must take into account the rhythmic nature of its expression and its impact on glucose tolerance over 24 h, specifically during the inactive/fasted phase. Ucp2 mRNA expression in MIN6 β cells and isolated islets is dynamic and rhythmic over 24 h. Daily cycles of glucose-stimulated insulin secretion capacity are dependent on rhythmic Ucp2 expression and UCP2 activity. Loss of rhythmic Ucp2 mRNA expression triggers glucose intolerance only in the light/inactive phase of the daily cycle. UCP2 is part of an endogenous diurnal metabolic regulator that coordinates islet function with the daily cycle of fasting and feeding.
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Key Words
- GSIS, Glucose-stimulated insulin secretion
- Glucose tolerance
- Glucose-stimulated insulin secretion
- HG, High glucose
- Ins2-cre, Ins2 promoter-driven cre recombinase
- LG, Low glucose
- MIN6, Mouse insulinoma 6
- Pancreatic islets
- T2D, Type 2 diabetes
- UCP2, Uncoupling protein 2
- Ucp2-βKO, β cell-specific Ucp2 knockout
- Uncoupling protein 2
- WT, wild type
- ZT, Zeitgeber time
- i.p.GTT, intraperitoneal glucose tolerance test
- β cells
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Affiliation(s)
- Nivedita Seshadri
- Univerisity of Manitoba, Department of Physiology and Pathophysiology, Winnipeg, MB, R3E 0J9, Canada.,The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Michael E Jonasson
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Kristin L Hunt
- Univerisity of Manitoba, Department of Physiology and Pathophysiology, Winnipeg, MB, R3E 0J9, Canada.,The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Bo Xiang
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada.,University of Manitoba, Department of Pharmacology & Therapeutics, Winnipeg, MB, R3E 0T6, Canada
| | - Steven Cooper
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Michael B Wheeler
- University of Toronto, Department of Physiology, Toronto, ON, M5S 1A8, Canada
| | - Vernon W Dolinsky
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada.,University of Manitoba, Department of Pharmacology & Therapeutics, Winnipeg, MB, R3E 0T6, Canada
| | - Christine A Doucette
- Univerisity of Manitoba, Department of Physiology and Pathophysiology, Winnipeg, MB, R3E 0J9, Canada.,The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
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Li L, Cheng WY, Glicksberg BS, Gottesman O, Tamler R, Chen R, Bottinger EP, Dudley JT. Identification of type 2 diabetes subgroups through topological analysis of patient similarity. Sci Transl Med 2016; 7:311ra174. [PMID: 26511511 DOI: 10.1126/scitranslmed.aaa9364] [Citation(s) in RCA: 287] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Type 2 diabetes (T2D) is a heterogeneous complex disease affecting more than 29 million Americans alone with a rising prevalence trending toward steady increases in the coming decades. Thus, there is a pressing clinical need to improve early prevention and clinical management of T2D and its complications. Clinicians have understood that patients who carry the T2D diagnosis have a variety of phenotypes and susceptibilities to diabetes-related complications. We used a precision medicine approach to characterize the complexity of T2D patient populations based on high-dimensional electronic medical records (EMRs) and genotype data from 11,210 individuals. We successfully identified three distinct subgroups of T2D from topology-based patient-patient networks. Subtype 1 was characterized by T2D complications diabetic nephropathy and diabetic retinopathy; subtype 2 was enriched for cancer malignancy and cardiovascular diseases; and subtype 3 was associated most strongly with cardiovascular diseases, neurological diseases, allergies, and HIV infections. We performed a genetic association analysis of the emergent T2D subtypes to identify subtype-specific genetic markers and identified 1279, 1227, and 1338 single-nucleotide polymorphisms (SNPs) that mapped to 425, 322, and 437 unique genes specific to subtypes 1, 2, and 3, respectively. By assessing the human disease-SNP association for each subtype, the enriched phenotypes and biological functions at the gene level for each subtype matched with the disease comorbidities and clinical differences that we identified through EMRs. Our approach demonstrates the utility of applying the precision medicine paradigm in T2D and the promise of extending the approach to the study of other complex, multifactorial diseases.
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Affiliation(s)
- Li Li
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 700 Lexington Ave., New York, NY 10065, USA
| | - Wei-Yi Cheng
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 700 Lexington Ave., New York, NY 10065, USA
| | - Benjamin S Glicksberg
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 700 Lexington Ave., New York, NY 10065, USA
| | - Omri Gottesman
- Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Ronald Tamler
- Division of Endocrinology, Diabetes, and Bone Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Rong Chen
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 700 Lexington Ave., New York, NY 10065, USA
| | - Erwin P Bottinger
- Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Joel T Dudley
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 700 Lexington Ave., New York, NY 10065, USA. Department of Health Policy and Research, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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Urbano F, Filippello A, Di Pino A, Barbagallo D, Di Mauro S, Pappalardo A, Rabuazzo AM, Purrello M, Purrello F, Piro S. Altered expression of uncoupling protein 2 in GLP-1-producing cells after chronic high glucose exposure: implications for the pathogenesis of diabetes mellitus. Am J Physiol Cell Physiol 2016; 310:C558-67. [DOI: 10.1152/ajpcell.00148.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 01/06/2016] [Indexed: 01/11/2023]
Abstract
Glucagon-like peptide-1 (GLP-1) is a gut L-cell hormone that enhances glucose-stimulated insulin secretion. Several approaches that prevent GLP-1 degradation or activate the GLP-1 receptor are being used to treat type 2 diabetes mellitus (T2DM) patients. In T2DM, GLP-1 secretion has been suggested to be impaired, and this defect appears to be a consequence rather than a cause of impaired glucose homeostasis. However, although defective GLP-1 secretion has been correlated with insulin resistance, little is known about the direct effects of chronic high glucose concentrations, which are typical in diabetes patients, on GLP-1-secreting cell function. In the present study, we demonstrate that glucotoxicity directly affects GLP-1 secretion in GLUTag cells chronically exposed to high glucose. Our results indicate that this abnormality is associated with a decrease in ATP production due to the elevated expression of mitochondrial uncoupling protein 2 (UCP2). Furthermore, UCP2 inhibition using small interfering RNA (siRNA) and the application of glibenclamide, an ATP-sensitive potassium (KATP+) channel blocker, reverse the GLP-1 secretion defect induced by chronic high-glucose treatment. These results show that glucotoxicity diminishes the secretory responsiveness of GLP-1-secreting cells to acute glucose stimulation. We conclude that the loss of the incretin effect, as observed in T2DM patients, could at least partially depend on hyperglycemia, which is typical in diabetes patients. Such an understanding may not only provide new insight into diabetes complications but also ultimately contribute to the identification of novel molecular targets within intestinal L-cells for controlling and improving endogenous GLP-1 secretion.
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Affiliation(s)
- Francesca Urbano
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
| | - Agnese Filippello
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
| | - Antonino Di Pino
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
| | - Davide Barbagallo
- Department of BioMedical Sciences and BioTechnology, section of Biology and Genetics Giovanni Sichel, Unit of Molecular, Genome and Complex Systems BioMedicine, University of Catania, Catania, Italy
| | - Stefania Di Mauro
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
| | - Alessandro Pappalardo
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
| | - Agata Maria Rabuazzo
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
| | - Michele Purrello
- Department of BioMedical Sciences and BioTechnology, section of Biology and Genetics Giovanni Sichel, Unit of Molecular, Genome and Complex Systems BioMedicine, University of Catania, Catania, Italy
| | - Francesco Purrello
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
| | - Salvatore Piro
- Department of Clinical and Experimental Medicine, Garibaldi-Nesima Hospital, University of Catania, Catania, Italy; and
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Chen L, So WY, Li SYT, Cheng Q, Boucher BJ, Leung PS. Niacin-induced hyperglycemia is partially mediated via niacin receptor GPR109a in pancreatic islets. Mol Cell Endocrinol 2015; 404:56-66. [PMID: 25622782 DOI: 10.1016/j.mce.2015.01.029] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 01/20/2015] [Accepted: 01/20/2015] [Indexed: 12/17/2022]
Abstract
The widely used lipid-lowering drug niacin is reported to induce hyperglycemia during chronic and high-dose treatments, but the mechanism is poorly understood. Recently, the niacin receptor [G-protein-coupled receptor, (GPR) 109a], has been localized to islet cells while its potential role therein remains unclear. We, therefore, aimed at investigating how GPR109a regulates islet beta-cell function and its downstream signaling using high-fat diet-induced obese mice and INS-1E beta cells. Eight-week niacin treatment elevated blood glucose concentration in obese mice with increased areas under the curve at oral glucose and intraperitoneal insulin tolerance tests. Additionally, niacin treatment significantly decreased glucose-stimulated insulin secretion (GSIS) but induced peroxisome proliferator-activated receptor gamma (Pparg) and GPR109a expression in isolated pancreatic islets; concomitantly, reactive oxygen species (ROS) were transiently increased, with decreases in GSIS, intracellular cyclic adenosine monophosphate (cAMP) accumulation and mitochondrial membrane potential (ΔΨm), but with increased expression of uncoupling protein 2 (Ucp2), Pparg and Gpr109a in INS-1E cells. Corroborating these findings, the decreases in GSIS, ΔΨm and cAMP production and increases in ROS, Pparg and GPR109a expression were abolished in INS-1E cells by GPR109a knockdown. Our data indicate that niacin-induced pancreatic islet dysfunction is probably modulated through activation of the islet beta-cell GPR109a-induced ROS-PPARγ-UCP2 pathways.
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Affiliation(s)
- Lihua Chen
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Wing Yan So
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Stephen Y T Li
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Qianni Cheng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Barbara J Boucher
- Centre for Diabetes, The Blizard Institute, Queen Mary University of London, London, UK
| | - Po Sing Leung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
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Lycopene modulates THP1 and Caco2 cells inflammatory state through transcriptional and nontranscriptional processes. Mediators Inflamm 2014; 2014:507272. [PMID: 24891766 PMCID: PMC4033542 DOI: 10.1155/2014/507272] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 04/11/2014] [Accepted: 04/11/2014] [Indexed: 01/06/2023] Open
Abstract
We revisited the action of a carotenoid, the lycopene, on the expression of proinflammatory genes, reactive oxygen species (ROS) production, and metalloprotease (MMP9) activity. THP1 and Caco2 cell lines were used as in vitro models for the two main cell types found in intestine tissue, that is, monocytes and epithelial cells. Proinflammatory condition was induced using either phorbol ester acetate (PMA), lipopolysaccharide (LPS) or tumor necrosis factor (TNF). In THP1 cells, short term pretreatment (2 h) with a low concentration (2 μM) of lycopene reinforce proinflammatory gene expression. The extent of the effect of lycopene is dependent on the proinflammtory stimulus (PMA, LPS or TNF) used. Lycopene enhanced MMP9 secretion via a c-AMP-dependent process, and reduced ROS production at higher concentrations than 2 μM. Cell culture media, conditioned by PMA-treated monocytes and then transferred on CaCo-2 epithelial cells, induced a proinflammatory state in these cells. The extent of this inflammatory effect was reduced when cells has been pretreated (12 h) with lycopene. At low concentration (2 μM or less), lycopene appeared to promote an inflammatory state not correlated with ROS modulation. At higher concentration (5 μM–20 μM), an anti-inflammatory effect takes place as a decrease of ROS production was detected. So, both concentration and time have to be considered in order to define the exact issue of the effect of carotenoids present in meals.
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Escobar J, Teramo K, Stefanovic V, Andersson S, Asensi MA, Arduini A, Cubells E, Sastre J, Vento M. Amniotic fluid oxidative and nitrosative stress biomarkers correlate with fetal chronic hypoxia in diabetic pregnancies. Neonatology 2013; 103:193-8. [PMID: 23295371 DOI: 10.1159/000345194] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 10/14/2012] [Indexed: 12/22/2022]
Abstract
BACKGROUND In spite of improvement in obstetrical care, pregnancy in women with type 1 diabetes mellitus is associated with increased perinatal morbidity and mortality. Hyperglycemia during pregnancy causes excessive fetal growth and chronic fetal hypoxia as reflected in increased erythropoietin (EPO) levels in amniotic fluid (AF). OBJECTIVES We hypothesized that the degree of fetal hypoxia would correlate with fetal oxidative and nitrosative stress as evidenced ty the concentration of specific biomarkers in AF. MATERIAL AND METHODS 19 pregnant women with type 1 or insulin-treated gestational diabetes mellitus were studied. AF samples were collected and processed for EPO, meta-tyrosine, nitro-tyrosine and 8-hydroxy-2-deoxiguanosine by chemiluminescent immunoassay and high-performance liquid chromatography coupled to tandem mass spectrometry methods, respectively. RESULTS The mean (SD) of the last HbA1c concentration before delivery was 7.7% (1.1). Median gestational age was 258 days (range 231-268). Birth weight was 3,868 ± 695 g with a z-score >2 SD in 47% of the cases. A significant correlation was found between the concentrations of AF EPO and meta-tyrosine/phenylalanine ratio (p < 0.001), nitro-tyrosine (p < 0.01) and 8-oxo-dG/2dG ratio (p < 0.001). CONCLUSIONS We confirmed that fetuses of type 1 diabetes or insulin-treated gestational diabetes pregnancies experience chronic hypoxia as reflected by increased EPO concentrations in AF near term. Moreover, EPO levels significantly correlated with the concentration of oxidative and nitrosative stress biomarkers in AF. This pro-oxidant status may predispose newborn infants to poor postnatal adaptation and early neonatal complications.
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Affiliation(s)
- Javier Escobar
- Neonatal Research Unit, Health Research Centre La Fe, University and Polytechnic Hospital La Fe, Valencia, Spain
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Impairment of Proinsulin Processing in β-Cells Exposed to Saturated Free Fatty Acid Is Dependent on Uncoupling Protein-2 Expression. Can J Diabetes 2012. [DOI: 10.1016/j.jcjd.2012.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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De Marinis YZ, Salehi A, Ward CE, Zhang Q, Abdulkader F, Bengtsson M, Braha O, Braun M, Ramracheya R, Amisten S, Habib AM, Moritoh Y, Zhang E, Reimann F, Rosengren A, Shibasaki T, Gribble F, Renström E, Seino S, Eliasson L, Rorsman P. GLP-1 inhibits and adrenaline stimulates glucagon release by differential modulation of N- and L-type Ca2+ channel-dependent exocytosis. Cell Metab 2010; 11:543-553. [PMID: 20519125 PMCID: PMC4310935 DOI: 10.1016/j.cmet.2010.04.007] [Citation(s) in RCA: 200] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Revised: 02/03/2010] [Accepted: 04/07/2010] [Indexed: 12/30/2022]
Abstract
Glucagon secretion is inhibited by glucagon-like peptide-1 (GLP-1) and stimulated by adrenaline. These opposing effects on glucagon secretion are mimicked by low (1-10 nM) and high (10 muM) concentrations of forskolin, respectively. The expression of GLP-1 receptors in alpha cells is <0.2% of that in beta cells. The GLP-1-induced suppression of glucagon secretion is PKA dependent, is glucose independent, and does not involve paracrine effects mediated by insulin or somatostatin. GLP-1 is without much effect on alpha cell electrical activity but selectively inhibits N-type Ca(2+) channels and exocytosis. Adrenaline stimulates alpha cell electrical activity, increases [Ca(2+)](i), enhances L-type Ca(2+) channel activity, and accelerates exocytosis. The stimulatory effect is partially PKA independent and reduced in Epac2-deficient islets. We propose that GLP-1 inhibits glucagon secretion by PKA-dependent inhibition of the N-type Ca(2+) channels via a small increase in intracellular cAMP ([cAMP](i)). Adrenaline stimulates L-type Ca(2+) channel-dependent exocytosis by activation of the low-affinity cAMP sensor Epac2 via a large increase in [cAMP](i).
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Affiliation(s)
- Yang Z De Marinis
- Lund University Diabetes Centre, Department of Clinical Sciences, Clinical Research Centre, Lund University, SE20502 Malmö, Sweden
| | - Albert Salehi
- Lund University Diabetes Centre, Department of Clinical Sciences, Clinical Research Centre, Lund University, SE20502 Malmö, Sweden
| | - Caroline E Ward
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Quan Zhang
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Fernando Abdulkader
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, 05508-00 São Paulo, Brazil
| | - Martin Bengtsson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Orit Braha
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Matthias Braun
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Reshma Ramracheya
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Stefan Amisten
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Abdella M Habib
- Cambridge Institute for Medical Research, Addenbrooke’s Hospital, University of Cambridge, Cambridge CB2 0XY, UK
| | - Yusuke Moritoh
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Enming Zhang
- Lund University Diabetes Centre, Department of Clinical Sciences, Clinical Research Centre, Lund University, SE20502 Malmö, Sweden
| | - Frank Reimann
- Cambridge Institute for Medical Research, Addenbrooke’s Hospital, University of Cambridge, Cambridge CB2 0XY, UK
| | - Anders Rosengren
- Lund University Diabetes Centre, Department of Clinical Sciences, Clinical Research Centre, Lund University, SE20502 Malmö, Sweden
| | - Tadao Shibasaki
- Division of Cellular and Molecular Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Fiona Gribble
- Cambridge Institute for Medical Research, Addenbrooke’s Hospital, University of Cambridge, Cambridge CB2 0XY, UK
| | - Erik Renström
- Lund University Diabetes Centre, Department of Clinical Sciences, Clinical Research Centre, Lund University, SE20502 Malmö, Sweden
| | - Susumu Seino
- Division of Cellular and Molecular Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Lena Eliasson
- Lund University Diabetes Centre, Department of Clinical Sciences, Clinical Research Centre, Lund University, SE20502 Malmö, Sweden
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
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beta-cell function in obese-hyperglycemic mice [ob/ob Mice]. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 654:463-77. [PMID: 20217510 DOI: 10.1007/978-90-481-3271-3_20] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
This review summarizes key aspects of what has been learned about the physiology of pancreatic islets and leptin deficiency from studies in obese ob/ob mice. ob/ob Mice lack functional leptin. They are grossly overweight and hyperphagic particularly at young ages and develop severe insulin resistance with hyperglycemia and hyperinsulinemia. ob/ob Mice have large pancreatic islets. The beta-cells respond adequately to most stimuli, and ob/ob mice have been used as a rich source of pancreatic islets with high insulin release capacity. ob/ob Mice can perhaps be described as a model for the prediabetic state. The large capacity for islet growth and insulin release makes ob/ob mice a good model for studies on how beta-cells can cope with prolonged functional stress.
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Saleh MC, Fatehi-Hassanabad Z, Wang R, Nino-Fong R, Wadowska DW, Wright GM, Harper ME, Chan CB. Mutated ATP synthase induces oxidative stress and impaired insulin secretion in beta-cells of female BHE/cdb rats. Diabetes Metab Res Rev 2008; 24:392-403. [PMID: 18273840 DOI: 10.1002/dmrr.819] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Adenosine triphosphate (ATP) is a critical determinant of beta-cell insulin secretion in response to glucose. BHE/cdb rats have a mutation in ATP synthase that limits ATP production, yet develop mild diabetes only with ageing. We investigated the cellular basis for reduced insulin secretion and compensatory mechanisms that mitigate the effects of the ATP synthase mutation. METHODS In vitro beta-cell function in isolated islets and expression of key regulatory genes was compared with in vivo oral glucose tolerance and insulin sensitivity in BHE/cdb and control rats. RESULTS BHE/cdb rat islets had reduced responsiveness to glucose stimulation and ATP content was 35% lower than in control islets. Oral glucose tolerance was impaired at both 21 and 43 weeks of age because of a reduction in glucose-stimulated insulin secretion (GSIS). An increase in inducible nitric oxide synthase (INOS, 3-fold) and manganese superoxide dismutase (MnSOD, 1.6-fold), detection of nitrotyrosine, beta-cell apoptosis, and nucleocytoplasmic translocation of pancreas duodenum homeobox-1 (PDX-1) in beta-cells indicated increased oxygen radical formation. However, BHE/cdb rats partially compensated for low glucose responsiveness by increasing the number of small islets and beta-cell hypertrophy. There was also an increase in the proportion of mature insulin relative to proinsulin (PI) detected within beta-cell granules. Increased activation of AMP-dependent kinase (AMPK)-regulated pathways was consistent with increased oxidative stress and with induction of apoptosis and reduction of preproinsulin gene transcription. CONCLUSIONS The findings are consistent with impaired but partially compensated mechanisms of insulin secretion early in life, but progressive non-compensated impairments due to oxidative stress occurs by age 43 weeks.
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Affiliation(s)
- Monique C Saleh
- Department of Biomedical Sciences, University of Prince Edward Island, Charlottetown, PE, Canada
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Kim SS, Son SM. Oxidative Stress and Cell Dysfunction in Diabetes: Role of ROS Produced by Mitochondria and NAD(P)H Oxidase. KOREAN DIABETES JOURNAL 2008. [DOI: 10.4093/kdj.2008.32.5.389] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Sang Soo Kim
- Department of Internal Medicine, Pusan National University School of Medicine, Korea
| | - Seok Man Son
- Department of Internal Medicine, Pusan National University School of Medicine, Korea
- Diabetes Center, Pusan National University Yangsan Hospital, Korea
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15
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Hua H, Sarvetnick N. ID2 promotes the expansion and survival of growth-arrested pancreatic beta cells. Endocrine 2007; 32:329-37. [PMID: 18322822 DOI: 10.1007/s12020-008-9039-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Revised: 01/11/2008] [Accepted: 01/14/2008] [Indexed: 10/22/2022]
Abstract
Inhibitors of DNA binding proteins (Ids) are implicated in the control of proliferation and differentiation. Herein, we tested the hypothesis that Id2 could stimulate proliferation and survival in differentiated pancreatic beta cells. We showed that Id2-enhanced proliferation of a growth-arrested pancreatic beta cell line (BTC-tet). This was mediated by the Rb pathway, as shown by an E2F1-driven reporter assay and Western immunoblot of phosphorylated Rb protein. Id2 also induced expression of Bcl-2, accompanied by a significant reduction of critical mediators of cytokine stimulation, including p38 MAPK and NFkappaB, as well as apoptosis markers, caspase-3 and Annexin-V. Overall, our data suggest that Id2 enhances proliferation and survival of growth-arrested BTC-tet cells.
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Affiliation(s)
- Hong Hua
- Department of Immunology, The Scripps Research Institute, 10550 N. Torrey Pines Rd., IMM-23, La Jolla, CA 92037, USA
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16
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Newsholme P, Haber EP, Hirabara SM, Rebelato ELO, Procopio J, Morgan D, Oliveira-Emilio HC, Carpinelli AR, Curi R. Diabetes associated cell stress and dysfunction: role of mitochondrial and non-mitochondrial ROS production and activity. J Physiol 2007; 583:9-24. [PMID: 17584843 PMCID: PMC2277225 DOI: 10.1113/jphysiol.2007.135871] [Citation(s) in RCA: 455] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
It is now widely accepted, given the current weight of experimental evidence, that reactive oxygen species (ROS) contribute to cell and tissue dysfunction and damage caused by glucolipotoxicity in diabetes. The source of ROS in the insulin secreting pancreatic beta-cells and in the cells which are targets for insulin action has been considered to be the mitochondrial electron transport chain. While this source is undoubtably important, we provide additional information and evidence for NADPH oxidase-dependent generation of ROS both in pancreatic beta-cells and in insulin sensitive cells. While mitochondrial ROS generation may be important for regulation of mitochondrial uncoupling protein (UCP) activity and thus disruption of cellular energy metabolism, the NADPH oxidase associated ROS may alter parameters of signal transduction, insulin secretion, insulin action and cell proliferation or cell death. Thus NADPH oxidase may be a useful target for intervention strategies based on reversing the negative impact of glucolipotoxicity in diabetes.
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Affiliation(s)
- P Newsholme
- School of Biomolecular and Biomedical Science, Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.
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Abstract
UCPs (uncoupling proteins) can regulate cellular ATP production by uncoupling oxidative phosphorylation. UCP2 is expressed in islet beta-cells and its induction reduces glucose-stimulated insulin secretion. Under physiological conditions, superoxide, formed as a by-product of respiration, activates UCP2. This leads to reduced ATP production, which impairs closure of the ATP-dependent K+ channels to prevent insulin secretion. It is suggested that the physiological role of UCP2 is to prevent excessive superoxide generation through a feedback loop. UCP2 induction may also alter fatty acid metabolism by altering NAD/NADH or by facilitating cycling of fatty acid anions. Recently, UCP2 has been proposed to keep insulin secretion low during starvation, a function under the control of the transcription co-repressor, surtuin-1, which has been shown to bind to the UCP2 promoter. Pathological UCP2 expression or activation may suppress glucose-stimulated insulin secretion to the extent that diabetes onset is hastened. In ob/ob mice, induction of UCP2 at age 5 weeks precedes development of insulin secretion defects and hyperglycaemia. Activating protein kinase A-dependent pathways can normalize insulin secretion in UCP2-overexpressing islets. Conversely, lowering UCP2 expression may promote increased insulin secretion. UCP2 knockout mice were protected from the diabetogenic effects of a high-fat diet and their islets exhibited increased sensitivity to glucose and elevated ATP/ADP. These results support a role for UCP2 as a gene contributing to the pathogenesis of Type 2 diabetes.
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Affiliation(s)
- C B Chan
- Department of Biomedical Sciences, University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, Canada C1A 4P3.
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