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Kong X, Yang C, Li B, Yan D, Yang Y, Cao C, Xing B, Ma X. FXR/Menin-mediated epigenetic regulation of E2F3 expression controls β-cell proliferation and is increased in islets from diabetic GK rats after RYGB. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167136. [PMID: 38531483 DOI: 10.1016/j.bbadis.2024.167136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 03/28/2024]
Abstract
Farnesoid X receptor (FXR) improves the function of islets, especially in the setting of Roux-en-Y gastric bypass (RYGB). Here we investigated how FXR activation regulates β-cell proliferation and explored the potential link between FXR signaling and the menin pathway in controlling E2F3 expression, a key transcription factor for controlling adult β-cell proliferation. Stimulation with the FXR agonist GW4064 or chenodeoxycholic acid (CDCA) increased E2F3 expression and β-cell proliferation. Consistently, E2F3 knockdown abolished GW4064-induced proliferation. Treatment with GW4064 increased E2F3 expression in β-cells via enhancing Steroid receptor coactivator-1 (SRC1) recruitment, increasing the pro-transcriptional acetylation of histone H3 at the E2f3 promoter. GW4064 treatment also decreased the association between FXR and menin, leading to the induction of FXR-mediated SRC1 recruitment. Mimicking the impact of FXR agonists, RYGB also increased E2F3 expression and β-cell proliferation in GK rats and SD rats. These findings unravel the crucial role of the FXR/menin signaling in epigenetically controlling E2F3 expression and β-cell proliferation, a mechanism possibly underlying RYGB-induced β-cell proliferation.
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Affiliation(s)
- Xiangchen Kong
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China
| | - Chenxi Yang
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China
| | - Bingfeng Li
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China
| | - Dan Yan
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China
| | - Yanhui Yang
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China
| | - Cuihua Cao
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China
| | - Bowen Xing
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China
| | - Xiaosong Ma
- Shenzhen University Diabetes Institute, School of Medicine, Shenzhen University, Shenzhen 518060, PR China.
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2
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Azad A, Altunbas HA, Manguoglu AE. From islet transplantation to beta-cell regeneration: an update on beta-cell-based therapeutic approaches in type 1 diabetes. Expert Rev Endocrinol Metab 2024; 19:217-227. [PMID: 38693782 DOI: 10.1080/17446651.2024.2347263] [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: 05/16/2023] [Accepted: 03/06/2024] [Indexed: 05/03/2024]
Abstract
INTRODUCTION Type 1 diabetes (T1D) mellitus is an autoimmune disease in which immune cells, predominantly effector T cells, destroy insulin-secreting beta-cells. Beta-cell destruction led to various consequences ranging from retinopathy and nephropathy to neuropathy. Different strategies have been developed to achieve normoglycemia, including exogenous glucose compensation, whole pancreas transplantation, islet transplantation, and beta-cell replacement. AREAS COVERED The last two decades of experience have shown that indigenous glucose compensation through beta-cell regeneration and protection is a peerless method for T1D therapy. Tremendous studies have tried to find an unlimited source for beta-cell regeneration, on the one hand, and beta-cell protection against immune attack, on the other hand. Recent advances in stem cell technology, gene editing methods, and immune modulation approaches provide a unique opportunity for both beta-cell regeneration and protection. EXPERT OPINION Pluripotent stem cell differentiation into the beta-cell is considered an unlimited source for beta-cell regeneration. Devising engineered pancreas-specific regulatory T cells using Chimeric Antigen Receptor (CAR) technology potentiates an effective immune tolerance induction for beta-cell protection. Beta-cell regeneration using pluripotent stem cells and beta-cell protection using pancreas-specific engineered regulatory T cells promises to develop a curative protocol in T1D.
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Affiliation(s)
- Asef Azad
- Department of Medical Biology, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Hasan Ali Altunbas
- Department of Endocrinology, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Ayse Esra Manguoglu
- Department of Medical Biology, Faculty of Medicine, Akdeniz University, Antalya, Turkey
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Luo J, Alkhalidy H, Jia Z, Liu D. Sulforaphane Ameliorates High-Fat-Diet-Induced Metabolic Abnormalities in Young and Middle-Aged Obese Male Mice. Foods 2024; 13:1055. [PMID: 38611359 PMCID: PMC11012181 DOI: 10.3390/foods13071055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 03/23/2024] [Accepted: 03/26/2024] [Indexed: 04/14/2024] Open
Abstract
Type 2 diabetes (T2D) is still a fast-growing health problem globally. It is evident that chronic insulin resistance (IR) and progressive loss of β-cell mass and function are key features of T2D etiology. Obesity is a leading pathogenic factor for developing IR. The aim of the present study was to determine whether sulforaphane (SFN), a natural compound derived from cruciferous vegetables, can prevent (prevention approach) or treat (treatment approach) obesity and IR in mouse models. We show that dietary intake of SFN (0.5 g/kg of HFD) for 20 weeks suppressed high-fat diet (HFD)-induced fat accumulation by 6.04% and improved insulin sensitivity by 23.66% in young male mice. Similarly, dietary provision of SFN (0.25 g/kg) significantly improved blood lipid profile, glucose tolerance, and insulin sensitivity of the middle-aged male mice while it had little effects on body composition as compared with the HFD group. In the treatment study, oral administration of SFN (40 mg/kg) induced weight loss and improved insulin sensitivity and plasma lipid profile in the diet-induced-obesity (DIO) male mice. In all three studies, the metabolic effects of SFN administration were not associated with changes in food intake. In vitro, SFN increased glucose uptake in C2C12 myotubes and increased fatty acid and pyruvate oxidation in primary human skeletal muscle cells. Our results suggest that SFN may be a naturally occurring insulin-sensitizing agent that is capable of improving the metabolic processes in HFD-induced obesity and IR and thereby may be a promising compound for T2D prevention.
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Affiliation(s)
- Jing Luo
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China;
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA;
| | - Hana Alkhalidy
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA;
- Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, Irbid 22110, Jordan
| | - Zhenquan Jia
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27412, USA;
| | - Dongmin Liu
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA;
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4
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Moore WT, Luo J, Liu D. Kaempferol improves glucose uptake in skeletal muscle via an AMPK-dependent mechanism. FOOD SCIENCE AND HUMAN WELLNESS 2023. [DOI: 10.1016/j.fshw.2023.03.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
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5
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Wang Y, Wu Y, Wang A, Wang A, Alkhalidy H, Helm R, Zhang S, Ma H, Zhang Y, Gilbert E, Xu B, Liu D. An olive-derived elenolic acid stimulates hormone release from L-cells and exerts potent beneficial metabolic effects in obese diabetic mice. Front Nutr 2022; 9:1051452. [PMID: 36386896 PMCID: PMC9664001 DOI: 10.3389/fnut.2022.1051452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023] Open
Abstract
Insulin resistance and progressive decline in functional β-cell mass are two key factors for developing type 2 diabetes (T2D), which is largely driven by overweight and obesity, a significant obstacle for effective metabolic control in many patients with T2D. Thus, agents that simultaneously ameliorate obesity and act on multiple pathophysiological components could be more effective for treating T2D. Here, we report that elenolic acid (EA), a phytochemical, is such a dual-action agent. we show that EA dose-dependently stimulates GLP-1 secretion in mouse clonal L-cells and isolated mouse ileum crypts. In addition, EA induces L-cells to secrete peptide YY (PYY). EA induces a rapid increase in intracellular [Ca2+]i and the production of inositol trisphosphate in L-cells, indicating that EA activates phospholipase C (PLC)-mediated signaling. Consistently, inhibition of (PLC) or Gαq ablates EA-stimulated increase of [Ca2+]i and GLP-1 secretion. In vivo, a single dose of EA acutely stimulates GLP-1 and PYY secretion in mice, accompanied with an improved glucose tolerance and insulin levels. Oral administration of EA at a dose of 50 mg/kg/day for 2 weeks normalized the fasting blood glucose and restored glucose tolerance in high-fat diet-induced obese (DIO) mice to levels that were comparable to chow-fed mice. In addition, EA suppresses appetite, reduces food intake, promotes weight loss, and reverses perturbated metabolic variables in obese mice. These results suggest that EA could be a dual-action agent as an alternative or adjuvant treatment for both T2D and obesity.
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Affiliation(s)
- Yao Wang
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Yajun Wu
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Aiping Wang
- College of Life Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Aihua Wang
- Department of Biochemistry, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Hana Alkhalidy
- Department of Nutrition and Food Technology, Jordan University of Science and Technology, Irbid, Jordan
| | - Richard Helm
- Department of Biochemistry, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Shijun Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, United States
| | - Hongguang Ma
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, United States
| | - Yan Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, United States
| | - Elizabeth Gilbert
- School of Animal Sciences, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Bin Xu
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Dongmin Liu
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, United States
- Virginia Tech Drug Discovery Center, Virginia Tech, Blacksburg, VA, United States
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6
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Martins Peçanha FL, Jaafar R, Werneck-de-Castro JP, Apostolopolou CC, Bhushan A, Bernal-Mizrachi E. The Transcription Factor YY1 Is Essential for Normal DNA Repair and Cell Cycle in Human and Mouse β-Cells. Diabetes 2022; 71:1694-1705. [PMID: 35594378 PMCID: PMC9490361 DOI: 10.2337/db21-0908] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 04/21/2022] [Indexed: 11/13/2022]
Abstract
Identifying the mechanisms behind the β-cell adaptation to failure is important to develop strategies to manage type 2 diabetes (T2D). Using db/db mice at early stages of the disease process, we took advantage of unbiased RNA sequencing to identify genes/pathways regulated by insulin resistance in β-cells. We demonstrate herein that islets from 4-week-old nonobese and nondiabetic leptin receptor-deficient db/db mice exhibited downregulation of several genes involved in cell cycle regulation and DNA repair. We identified the transcription factor Yin Yang 1 (YY1) as a common gene between both pathways. The expression of YY1 and its targeted genes was decreased in the db/db islets. We confirmed the reduction in YY1 expression in β-cells from diabetic db/db mice, mice fed a high-fat diet (HFD), and individuals with T2D. Chromatin immunoprecipitation sequencing profiling in EndoC-βH1 cells, a human pancreatic β-cell line, indicated that YY1 binding regions regulate cell cycle control and DNA damage recognition and repair. We then generated mouse models with constitutive and inducible YY1 deficiency in β-cells. YY1-deficient mice developed diabetes early in life due to β-cell loss. β-Cells from these mice exhibited higher DNA damage, cell cycle arrest, and cell death as well as decreased maturation markers. Tamoxifen-induced YY1 deficiency in mature β-cells impaired β-cell function and induced DNA damage. In summary, we identified YY1 as a critical factor for β-cell DNA repair and cell cycle progression.
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Affiliation(s)
| | - Rami Jaafar
- Diabetes Center, University of California, San Francisco, San Francisco, CA
| | - Joao Pedro Werneck-de-Castro
- Division of Endocrinology, Diabetes and Metabolism, University of Miami, Miller School of Medicine, Miami, FL
- Miami Veterans Affairs Health Care System, Miami, FL
| | | | - Anil Bhushan
- Diabetes Center, University of California, San Francisco, San Francisco, CA
| | - Ernesto Bernal-Mizrachi
- Division of Endocrinology, Diabetes and Metabolism, University of Miami, Miller School of Medicine, Miami, FL
- Miami Veterans Affairs Health Care System, Miami, FL
- Corresponding author: Ernesto Bernal-Mizrachi,
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7
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Todero JE, Koch-Laskowski K, Shi Q, Kanke M, Hung YH, Beck R, Styblo M, Sethupathy P. Candidate master microRNA regulator of arsenic-induced pancreatic beta cell impairment revealed by multi-omics analysis. Arch Toxicol 2022; 96:1685-1699. [PMID: 35314868 PMCID: PMC9095563 DOI: 10.1007/s00204-022-03263-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/17/2022] [Indexed: 02/05/2023]
Abstract
Arsenic is a pervasive environmental toxin that is listed as the top priority for investigation by the Agency for Toxic Substance and Disease Registry. While chronic exposure to arsenic is associated with type 2 diabetes (T2D), the underlying mechanisms are largely unknown. We have recently demonstrated that arsenic treatment of INS-1 832/13 pancreatic beta cells impairs glucose-stimulated insulin secretion (GSIS), a T2D hallmark. We have also shown that arsenic alters the microRNA profile of beta cells. MicroRNAs have a well-established post-transcriptional regulatory role in both normal beta cell function and T2D pathogenesis. We hypothesized that there are microRNA master regulators that shape beta cell gene expression in pathways pertinent to GSIS after exposure to arsenicals. To test this hypothesis, we first treated INS-1 832/13 beta cells with either inorganic arsenic (iAsIII) or monomethylarsenite (MAsIII) and confirmed GSIS impairment. We then performed multi-omic analysis using chromatin run-on sequencing, RNA-sequencing, and small RNA-sequencing to define profiles of transcription, gene expression, and microRNAs, respectively. Integrating across these data sets, we first showed that genes downregulated by iAsIII treatment are enriched in insulin secretion and T2D pathways, whereas genes downregulated by MAsIII treatment are enriched in cell cycle and critical beta cell maintenance factors. We also defined the genes that are subject primarily to post-transcriptional control in response to arsenicals and demonstrated that miR-29a is the top candidate master regulator of these genes. Our results highlight the importance of microRNAs in arsenical-induced beta cell dysfunction and reveal both shared and unique mechanisms between iAsIII and MAsIII.
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Affiliation(s)
- Jenna E Todero
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Kieran Koch-Laskowski
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Qing Shi
- Department of Nutrition, Gillings School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Matt Kanke
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Yu-Han Hung
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Rowan Beck
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
- Department of Nutrition, Gillings School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Miroslav Styblo
- Department of Nutrition, Gillings School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Praveen Sethupathy
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
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8
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Desentis-Desentis MF. Regenerative approaches to preserve pancreatic β-cell mass and function in diabetes pathogenesis. Endocrine 2022; 75:338-350. [PMID: 34825343 DOI: 10.1007/s12020-021-02941-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 11/07/2021] [Indexed: 01/21/2023]
Abstract
In both type 1 diabetes (T1D) and type 2 diabetes (T2D), there is a substantial β-cell mass loss. Residual β-cell mass is susceptible to cellular damage because of specific pancreatic β-cell characteristics. β cells have a low proliferation rate, being in human adults almost zero and a low antioxidant system that makes β cells susceptible to oxidative stress and increases their vulnerability to cell destruction. Different strategies have been addressed to preserve pancreatic β-cell residual mass and function in patients with diabetes. However, the effect of many compounds proposed in rodent models to trigger β-cell replication has different results in human β cells. In this review, scientific evidence of β-cell of two major regenerative approaches has been gathered. Regeneration proceedings for pancreatic β cells are promising and could improve β-cell proliferation capacity and contribute to the conservation of mature β-cell phenotypic characteristics. This evidence supports the notion that regenerative medicine could be a helpful strategy to yield amelioration of T1D and T2D pathogenesis.
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Affiliation(s)
- Maria Fernanda Desentis-Desentis
- Department of Molecular Biology and Genomics, University Center for Health Sciences, University of Guadalajara, Jalisco, Mexico.
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9
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Walker JT, Saunders DC, Brissova M, Powers AC. The Human Islet: Mini-Organ With Mega-Impact. Endocr Rev 2021; 42:605-657. [PMID: 33844836 PMCID: PMC8476939 DOI: 10.1210/endrev/bnab010] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Indexed: 02/08/2023]
Abstract
This review focuses on the human pancreatic islet-including its structure, cell composition, development, function, and dysfunction. After providing a historical timeline of key discoveries about human islets over the past century, we describe new research approaches and technologies that are being used to study human islets and how these are providing insight into human islet physiology and pathophysiology. We also describe changes or adaptations in human islets in response to physiologic challenges such as pregnancy, aging, and insulin resistance and discuss islet changes in human diabetes of many forms. We outline current and future interventions being developed to protect, restore, or replace human islets. The review also highlights unresolved questions about human islets and proposes areas where additional research on human islets is needed.
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Affiliation(s)
- John T Walker
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Diane C Saunders
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Marcela Brissova
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Alvin C Powers
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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10
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Barella LF, Rossi M, Pydi SP, Meister J, Jain S, Cui Y, Gavrilova O, Fulgenzi G, Tessarollo L, Wess J. β-Arrestin-1 is required for adaptive β-cell mass expansion during obesity. Nat Commun 2021; 12:3385. [PMID: 34099679 PMCID: PMC8184739 DOI: 10.1038/s41467-021-23656-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/11/2021] [Indexed: 01/14/2023] Open
Abstract
Obesity is the key driver of peripheral insulin resistance, one of the key features of type 2 diabetes (T2D). In insulin-resistant individuals, the expansion of beta-cell mass is able to delay or even prevent the onset of overt T2D. Here, we report that beta-arrestin-1 (barr1), an intracellular protein known to regulate signaling through G protein-coupled receptors, is essential for beta-cell replication and function in insulin-resistant mice maintained on an obesogenic diet. Specifically, insulin-resistant beta-cell-specific barr1 knockout mice display marked reductions in beta-cell mass and the rate of beta-cell proliferation, associated with pronounced impairments in glucose homeostasis. Mechanistic studies suggest that the observed metabolic deficits are due to reduced Pdx1 expression levels caused by beta-cell barr1 deficiency. These findings indicate that strategies aimed at enhancing barr1 activity and/or expression in beta-cells may prove useful to restore proper glucose homeostasis in T2D.
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Affiliation(s)
- Luiz F Barella
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA.
| | - Mario Rossi
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Sai P Pydi
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Jaroslawna Meister
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Shanu Jain
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Yinghong Cui
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Oksana Gavrilova
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Bethesda, MD, USA
| | - Gianluca Fulgenzi
- Mouse Cancer Genetics Program, National Cancer Institute, Frederick, MD, USA
| | - Lino Tessarollo
- Mouse Cancer Genetics Program, National Cancer Institute, Frederick, MD, USA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA.
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11
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Liu JY, Zhang YC, Xie RR, Song LN, Yang WL, Xin Z, Cao X, Yang JK. Nifuroxazide improves insulin secretion and attenuates high glucose-induced inflammation and apoptosis in INS-1 cells. Eur J Pharmacol 2021; 899:174042. [PMID: 33745960 DOI: 10.1016/j.ejphar.2021.174042] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 12/14/2022]
Abstract
Inflammation and oxidative stress are important factors that cause islet β-cell dysfunction. STAT3 is not only a major factor in cell proliferation and differentiation, but also plays an important role in mediating inflammation. As a potent inhibitor of STAT3, the effect of Nifuroxazide (Nifu) on pancreatic islet cells in a high glucose environment has not been reported. In the present study, we used high concentration glucose-induced INS-1 cells to examine the effects of Nifu on high glucose-induced cell function by glucose-stimulated insulin secretion (GSIS). The effects of Nifu on high glucose-induced oxidative stress were recorded by oxidative factors and antioxidant factors. Simultaneously, the effect of Nifu on the inflammatory response, apoptosis, and STAT3/SOCS3 signal pathway were validated by quantitative real-time PCR (qRT-PCR) and Western blot. Our study indicated that Nifu significantly improved cell vitality and insulin secretion of INS-1 cells induced by high glucose. We found Nifu significantly inhibited pro-oxidative factors (ROS, MDA) and promoted anti-oxidative factors (SOD, GSH-PX, CAT). Meanwhile, qRT-PCR and Western blot results showed that inflammatory and apoptosis factors were remarkably inhibited by Nifu. Further research indicated that Nifu clearly suppressed the activation of the STAT3/SOCS3 signaling pathway. In conclusion, Nifu can significantly improve the insulin secretion function, protect oxidative stress injury, and reduce inflammatory response and apoptosis in high glucose-induced INS-1 cells. Therefore, Nifu has a new positive effect on maintaining the normal function of pancreatic islet cells in a high glucose environment and provides new drug candidates for the treatment and prevention of diabetes.
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Affiliation(s)
- Jing-Yi Liu
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
| | - Yi-Chen Zhang
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
| | - Rong-Rong Xie
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
| | - Li-Ni Song
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
| | - Wei-Li Yang
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
| | - Zhong Xin
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
| | - Xi Cao
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China.
| | - Jin-Kui Yang
- Beijing Diabetes Institute, Beijing Key Laboratory of Diabetes Research and Care, Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China.
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12
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CDK2 limits the highly energetic secretory program of mature β cells by restricting PEP cycle-dependent K ATP channel closure. Cell Rep 2021; 34:108690. [PMID: 33503433 PMCID: PMC7882066 DOI: 10.1016/j.celrep.2021.108690] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 11/24/2020] [Accepted: 01/04/2021] [Indexed: 12/23/2022] Open
Abstract
Hallmarks of mature β cells are restricted proliferation and a highly energetic secretory state. Paradoxically, cyclin-dependent kinase 2 (CDK2) is synthesized throughout adulthood, its cytosolic localization raising the likelihood of cell cycle-independent functions. In the absence of any changes in β cell mass, maturity, or proliferation, genetic deletion of Cdk2 in adult β cells enhanced insulin secretion from isolated islets and improved glucose tolerance in vivo. At the single β cell level, CDK2 restricts insulin secretion by increasing KATP conductance, raising the set point for membrane depolarization in response to activation of the phosphoenolpyruvate (PEP) cycle with mitochondrial fuels. In parallel with reduced β cell recruitment, CDK2 restricts oxidative glucose metabolism while promoting glucose-dependent amplification of insulin secretion. This study provides evidence of essential, non-canonical functions of CDK2 in the secretory pathways of quiescent β cells. Despite loss of proliferative capacity with age, mature β cells continually synthesize CDK2. Sdao et al. demonstrate that CDK2 depletion in adult β cells improves glucose tolerance in vivo. By augmenting PEP cycle-dependent KATP channel closure, CDK2 inactivation lowers the set point for membrane depolarization, augmenting oxidative metabolism and insulin secretion.
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13
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Stafford JD, Yeo CT, Corbett JA. Inhibition of oxidative metabolism by nitric oxide restricts EMCV replication selectively in pancreatic beta-cells. J Biol Chem 2020; 295:18189-18198. [PMID: 33100269 PMCID: PMC7939444 DOI: 10.1074/jbc.ra120.015893] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/08/2020] [Indexed: 01/27/2023] Open
Abstract
Environmental factors, such as viral infection, are proposed to play a role in the initiation of autoimmune diabetes. In response to encephalomyocarditis virus (EMCV) infection, resident islet macrophages release the pro-inflammatory cytokine IL-1β, to levels that are sufficient to stimulate inducible nitric oxide synthase (iNOS) expression and production of micromolar levels of the free radical nitric oxide in neighboring β-cells. We have recently shown that nitric oxide inhibits EMCV replication and EMCV-mediated β-cell lysis and that this protection is associated with an inhibition of mitochondrial oxidative metabolism. Here we show that the protective actions of nitric oxide against EMCV infection are selective for β-cells and associated with the metabolic coupling of glycolysis and mitochondrial oxidation that is necessary for insulin secretion. Inhibitors of mitochondrial respiration attenuate EMCV replication in β-cells, and this inhibition is associated with a decrease in ATP levels. In mouse embryonic fibroblasts (MEFs), inhibition of mitochondrial metabolism does not modify EMCV replication or decrease ATP levels. Like most cell types, MEFs have the capacity to uncouple the glycolytic utilization of glucose from mitochondrial respiration, allowing for the maintenance of ATP levels under conditions of impaired mitochondrial respiration. It is only when MEFs are forced to use mitochondrial oxidative metabolism for ATP generation that mitochondrial inhibitors attenuate viral replication. In a β-cell selective manner, these findings indicate that nitric oxide targets the same metabolic pathways necessary for glucose stimulated insulin secretion for protection from viral lysis.
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Affiliation(s)
- Joshua D Stafford
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Chay Teng Yeo
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
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14
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Stafford JD, Shaheen ZR, Yeo CT, Corbett JA. Inhibition of mitochondrial oxidative metabolism attenuates EMCV replication and protects β-cells from virally mediated lysis. J Biol Chem 2020; 295:16655-16664. [PMID: 32972972 PMCID: PMC7864063 DOI: 10.1074/jbc.ra120.014851] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/06/2020] [Indexed: 12/15/2022] Open
Abstract
Viral infection is one environmental factor that may contribute to the initiation of pancreatic β-cell destruction during the development of autoimmune diabetes. Picornaviruses, such as encephalomyocarditis virus (EMCV), induce a pro-inflammatory response in islets leading to local production of cytokines, such as IL-1, by resident islet leukocytes. Furthermore, IL-1 is known to stimulate β-cell expression of iNOS and production of the free radical nitric oxide. The purpose of this study was to determine whether nitric oxide contributes to the β-cell response to viral infection. We show that nitric oxide protects β-cells against virally mediated lysis by limiting EMCV replication. This protection requires low micromolar, or iNOS-derived, levels of nitric oxide. At these concentrations nitric oxide inhibits the Krebs enzyme aconitase and complex IV of the electron transport chain. Like nitric oxide, pharmacological inhibition of mitochondrial oxidative metabolism attenuates EMCV-mediated β-cell lysis by inhibiting viral replication. These findings provide novel evidence that cytokine signaling in β-cells functions to limit viral replication and subsequent β-cell lysis by attenuating mitochondrial oxidative metabolism in a nitric oxide-dependent manner.
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Affiliation(s)
- Joshua D Stafford
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Zachary R Shaheen
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Chay Teng Yeo
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
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15
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Wang Y, Wang A, Alkhalidy H, Luo J, Moomaw E, Neilson AP, Liu D. Flavone Hispidulin Stimulates Glucagon-Like Peptide-1 Secretion and Ameliorates Hyperglycemia in Streptozotocin-Induced Diabetic Mice. Mol Nutr Food Res 2020; 64:e1900978. [PMID: 31967385 DOI: 10.1002/mnfr.201900978] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 12/24/2019] [Indexed: 12/17/2022]
Abstract
SCOPE Loss of functional β-cell mass is central for the deterioration of glycemic control in diabetes. The incretin hormone glucagon-like peptide-1 (GLP-1) plays a critical role in maintaining glycemic homeostasis via potentiating glucose-stimulated insulin secretion and promoting β-cell mass. Agents that can directly promote GLP-1 secretion, thereby increasing insulin secretion and preserving β-cell mass, hold great potential for the treatment of T2D. METHODS AND RESULTS GluTag L-cells, INS832/13 cells, and mouse ileum crypts and islets are cultured for examining the effects of flavone hispidulin on GLP-1 and insulin secretion. Mouse livers and isolated hepatocytes are used for gluconeogenesis. Streptozotocin-induced diabetic mice are treated with hispidulin (20 mg kg-1 day-1 , oral gavage) for 6 weeks to evaluate its anti-diabetic potential. Hispidulin stimulates GLP-1 secretion from the L-cell line, ileum crypts, and in vivo. This hispidulin action is mediated via activation of cyclic adenosine monophosphate/protein kinase A signaling. Hispidulin significantly improves glycemic control in diabetic mice, concomitant with improved insulin release, and β-cell survival. Additionally, hispidulin decreases hepatic pyruvate carboxylase expression in diabetic mice and suppresses gluconeogenesis in hepatocytes. Furthermore, hispidulin stimulates insulin secretion from β-cells. CONCLUSION These findings suggest that Hispidulin may be a novel dual-action anti-diabetic compound via stimulating GLP-1 secretion and suppressing hepatic glucose production.
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Affiliation(s)
- Yao Wang
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, 24060, USA
| | - Aiping Wang
- College of Life Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Hana Alkhalidy
- Department of Nutrition and Food Technology, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Jing Luo
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, 24060, USA
| | - Elizabeth Moomaw
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, 24060, USA
| | - Andrew P Neilson
- Plants for Human Health Institution, North Carolina State University, Kannapolis, NC, 28081, USA
| | - Dongmin Liu
- Department of Human Nutrition, Foods, and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA, 24060, USA
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16
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Hu L, He F, Luo Y, Luo H, Hai L, Li Y, Zhou Z, Liu F, Dai YS. Reduced Compensatory β-Cell Proliferation in Nfatc3-Deficient Mice Fed on High-Fat Diet. Exp Clin Endocrinol Diabetes 2019; 129:651-660. [PMID: 31546271 DOI: 10.1055/a-1008-9110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND High-fat-diet induces pancreatic β-cell compensatory proliferation, and impairments in pancreatic β-cell proliferation and function can lead to defects in insulin secretion and diabetes. NFATc3 is important for HFD-induced adipose tissue inflammation. But it is unknown whether NFATc3 is required for β cell compensatory growth in mice fed with HFD. METHODS NFATc3 mRNA and protein expression levels were quantified by RT-qPCR and Western blotting, respectively, in pancreatic islets of WT mice fed on HFD for 12-20 weeks. Adenoviral-mediated overexpression of NFATc3 were conducted in Min6 cells and cultured primary mouse islets. NFATc3-/- mice and WT control mice were fed with HFD and metabolic and functional parameters were measured. RESULTS We observed that the NFATc3 expression level was reduced in the islets of high-fat-diet (HFD)-fed mice. Adenovirus-mediated overexpression of NFATc3 enhanced glucose-stimulated insulin secretion and β-cell gene expression in cultured primary mouse islets. Nfatc3-/- mice initially developed similar glucose tolerance at 2-4 weeks after HFD feeding than HFD-fed WT mice, but Nfatc3-/- mice developed improved glucose tolerance and insulin sensitivity after 8 weeks of HFD feeding compared to Nfatc3+/+fed with HFD. Furthermore, Nfatc3-/- mice on HFD exhibited decreased β-cell mass and reduced expression of genes important for β-cell proliferation and function compared to Nfatc3+/+mice on HFD. CONCLUSIONS The findings suggested that NFATc3 plays a role in maintaining the pancreatic β-cell compensatory growth and gene expression in response to obesity.
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Affiliation(s)
- Li Hu
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Fengli He
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yan Luo
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hairong Luo
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Luo Hai
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yabin Li
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhiguang Zhou
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Feng Liu
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Yan-Shan Dai
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Metabolic Disease, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.,Bristol-Myers Squibb Company, Princeton, NJ 08540, United States
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17
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Trimal K, Shah T, Joshi K, Mulla G. Association of EGF A61G polymorphism and EGF expression with type 2 diabetes mellitus in Indian population. GENE REPORTS 2019. [DOI: 10.1016/j.genrep.2019.100384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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18
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Zhong F, Jiang Y. Endogenous Pancreatic β Cell Regeneration: A Potential Strategy for the Recovery of β Cell Deficiency in Diabetes. Front Endocrinol (Lausanne) 2019; 10:101. [PMID: 30842756 PMCID: PMC6391341 DOI: 10.3389/fendo.2019.00101] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 02/04/2019] [Indexed: 12/11/2022] Open
Abstract
Endogenous pancreatic β cell regeneration is a potential strategy for β cell expansion or neogenesis to treat diabetes. Regeneration can occur through stimulation of existing β cell replication or conversion of other pancreatic cells into β cells. Recently, various strategies and approaches for stimulation of endogenous β cell regeneration have been evaluated, but they were not suitable for clinical application. In this paper, we comprehensively review these strategies, and further discuss various factors involved in regulation of β cell regeneration under physiological or pathological conditions, such as mediators, transcription factors, signaling pathways, and potential pharmaceutical drugs. Furthermore, we discuss possible reasons for the failure of regenerative medicines in clinical trials, and possible strategies for improving β cell regeneration. As β cell heterogeneity and plasticity determines their function and environmental adaptability, we focus on β cell subtype markers and discuss the importance of research evaluating the characteristics of new β cells. In addition, based on the autoimmunologic features of type 1 diabetes, NOD/Lt-SCID-IL2rg null (NSG) mice grafted with human immune cells and β cells are recommended for use in evaluation of antidiabetic regenerative medicines. This review will further understand current advances in endogenous β cell regeneration, and provide potential new strategies for the treatment of diabetes focused on cell therapy.
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Affiliation(s)
- Fan Zhong
- Department of Gastroenterology, Songjiang Hospital Affiliated First People's Hospital, Shanghai Jiao Tong University, Shanghai, China
- Institutes of Biomedical Sciences of Shanghai Medical College, Fudan University, Shanghai, China
| | - Yan Jiang
- Institutes of Biomedical Sciences of Shanghai Medical College, Fudan University, Shanghai, China
- *Correspondence: Yan Jiang
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19
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Oleson BJ, Corbett JA. Dual Role of Nitric Oxide in Regulating the Response of β Cells to DNA Damage. Antioxid Redox Signal 2018; 29:1432-1445. [PMID: 28978225 PMCID: PMC6166691 DOI: 10.1089/ars.2017.7351] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 09/09/2017] [Indexed: 01/09/2023]
Abstract
SIGNIFICANCE Cytokines released in and around pancreatic islets during islet inflammation are believed to contribute to impaired β cell function and β cell death during the development of diabetes. Nitric oxide, produced by β cells in response to cytokine exposure, controls many of the responses of β cells during islet inflammation. Recent Advances: Although nitric oxide has been shown to inhibit insulin secretion and oxidative metabolism and induce DNA damage in β cells, it also activates protective pathways that promote recovery of insulin secretion and oxidative metabolism and repair of damaged DNA. Recent studies have identified a novel role for nitric oxide in selectively regulating the DNA damage response in β cells. CRITICAL ISSUES Does nitric oxide mediate cytokine-induced β cell damage, or is nitric oxide produced by β cells in response to cytokines to protect β cells from damage? FUTURE DIRECTIONS β cells appear to be the only islet endocrine cell type capable of responding to proinflammatory cytokines with the production of nitric oxide, and these terminally differentiated cells have a limited capacity to regenerate. It is likely that there is a physiological purpose for this response, and understanding this could open new areas of study regarding the loss of functional β cell mass during diabetes development.
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Affiliation(s)
- Bryndon J. Oleson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - John A. Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
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20
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Shi S, Zhao L, Zheng L. NSD2 is downregulated in T2DM and promotes β cell proliferation and insulin secretion through the transcriptionally regulation of PDX1. Mol Med Rep 2018; 18:3513-3520. [PMID: 30066931 DOI: 10.3892/mmr.2018.9338] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Accepted: 06/27/2018] [Indexed: 11/06/2022] Open
Abstract
Diabetes has become a major public health issue in the world. Type 2 diabetes mellitus (T2DM), also known as non‑insulin‑dependent diabetes mellitus, has been identified to result in an inability to compensate for insulin resistance. A previous study has shown that NSD2 regulates glucose metabolism; however, whether NSD2 serves roles in diabetes has not been thoroughly elucidated to date. In present study, the expression of NSD2 in blood samples from patients with T2DM was compared with that in healthy volunteers. Notably, the expression of NSD2 was negatively correlated with glucose concentration but positively associated with PDX1 expression. Several functional experiments, including CCK‑8 assay and colony formation assay, revealed that NSD2 promoted the proliferation of pancreatic β cell lines. Moreover, ectopic expression of NSD2 significantly promoted insulin secretion. In addition, NSD2 served as a transfection factor and it was identified that NSD2 transcriptionally regulated PDX1 expression through its H3K36me2 methyltransferase activity. The present study indicated that NSD2 may be a novel molecular therapy target of T2DM.
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Affiliation(s)
- Suqin Shi
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Lu Zhao
- Department of Endocrinology, The Third Affiliated Hospital of Henan University of TCM, Zhengzhou, Henan 450004, P.R. China
| | - Lili Zheng
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
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21
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Ma Y, Fei X. SIRT5 regulates pancreatic β-cell proliferation and insulin secretion in type 2 diabetes. Exp Ther Med 2018; 16:1417-1425. [PMID: 30116390 DOI: 10.3892/etm.2018.6301] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 10/27/2017] [Indexed: 12/14/2022] Open
Abstract
Impaired insulin secretion and insulin resistance are the primary characteristics of type 2 diabetes (T2D). However, the mechanisms underlying insulin secretion failure have yet to be elucidated. The present study demonstrated that sirtuin 5 (SIRT5) is upregulated in patients with T2D and in pancreatic β-cell lines. It was also revealed that elevated SIRT5 expression is positively associated with age and blood glucose levels, and negatively associated with pancreatic and duodenal homeobox 1 (PDX1) expression. Colony formation and Cell Counting Kit-8 assays demonstrated that SIRT5 suppressed the proliferation of pancreatic β-cells in vitro. In addition, downregulation of SIRT5 promoted the secretion of insulin. Additionally, SIRT5 ectopic expression downregulated the expression of PDX1 and the inhibition of SIRT5 upregulated PDX1 expression. Chromatin immunoprecipitation assay analysis demonstrated that SIRT5 may regulate the transcription of PDX1 via H4K16 deacetylation. In conclusion, the results of the present study indicate that SIRT5 may serve an important role in the pathogenesis of T2D, and may present a novel therapeutic target for the treatment of patients with T2D.
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Affiliation(s)
- Yongmei Ma
- Department of Endocrinology, Taizhou People's Hospital, Taizhou, Jiangsu 225300, P.R. China
| | - Xiaoqiang Fei
- Department of Endocrinology, Taizhou People's Hospital, Taizhou, Jiangsu 225300, P.R. China
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22
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Luo J, Wang A, Zhen W, Wang Y, Si H, Jia Z, Alkhalidy H, Cheng Z, Gilbert E, Xu B, Liu D. Phytonutrient genistein is a survival factor for pancreatic β-cells via GPR30-mediated mechanism. J Nutr Biochem 2018; 58:59-70. [PMID: 29885598 DOI: 10.1016/j.jnutbio.2018.04.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Revised: 03/29/2018] [Accepted: 04/27/2018] [Indexed: 12/31/2022]
Abstract
We previously discovered that phytonutrient genistein rapidly activates cAMP signaling in β-cells and improves islet mass in diabetic mice. However, the mechanism underlying these actions of genistein is still unclear. Here, we show that pharmacological or molecular inhibition of Gαs blocked genistein-stimulated adenylate cyclase activity in plasma membrane and intracellular cAMP production in INS1 cells and islets. Further, genistein stimulation of cAMP generation was abolished in islets exposed to a specific GPR30 inhibitor G15 or islets from GPR30 deficient (GPR30-/-) mice. In vivo, dietary provision of genistein (0.5 g/kg diet) significantly mitigated streptozotocin-induced hyperglycemia in male WT mice, which was associated with improved blood insulin levels and pancreatic islet mass and survival, whereas these effects were absent in Gpr30-/- mice. Genistein treatment promoted survival of INS1 cells and human islets chronically exposed to palmitate and high glucose. At molecular level, genistein activated CREB phosphorylation and subsequently induced Bcl-2 expression, and knockdown of CREB diminished the protective effect of genistein on β-cells induced by lipoglucotoxicity. Finally, deletion of GPR30 in β-cells or islets ablated genistein-induced CREB phosphorylation and its cytoprotective effect. These findings demonstrate that genistein is a survival factor for β-cells via GPR30-initiated, Gαs-mediated activation of CREB.
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Affiliation(s)
- Jing Luo
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA
| | - Aihua Wang
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA
| | - Wei Zhen
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA
| | - Yao Wang
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA
| | - Hongwei Si
- Department of Human Sciences, College of Agriculture, Human, and Natural Sciences, Tennessee State University, Nashville, TN
| | - Zhenquan Jia
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC
| | - Hana Alkhalidy
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA; Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, Irbid 22110, Jordan
| | - Zhiyong Cheng
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA
| | - Elizabeth Gilbert
- Department of Animal and Poultry Sciences, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA
| | - Bin Xu
- Department of Biochemistry, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA
| | - Dongmin Liu
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA.
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23
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Alkhalidy H, Wang Y, Liu D. Dietary Flavonoids in the Prevention of T2D: An Overview. Nutrients 2018; 10:nu10040438. [PMID: 29614722 PMCID: PMC5946223 DOI: 10.3390/nu10040438] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/15/2018] [Accepted: 03/29/2018] [Indexed: 12/16/2022] Open
Abstract
Type 2 diabetes (T2D) is a progressive metabolic disease that is increasing in prevalence globally. It is well established that insulin resistance (IR) and a progressive decline in functional β-cell mass are hallmarks of developing T2D. Obesity is a leading pathogenic factor for developing IR. Constant IR will progress to T2D when β-cells are unable to secret adequate amounts of insulin to compensate for decreased insulin sensitivity. Recently, a considerable amount of research has been devoted to identifying naturally occurring anti-diabetic compounds that are abundant in certain types of foods. Flavonoids are a group of polyphenols that have drawn great interest for their various health benefits. Results from many clinical and animal studies demonstrate that dietary intake of flavonoids might be helpful in preventing T2D, although cellular and molecular mechanisms underlying these effects are still not completely understood. This review discusses our current understanding of the pathophysiology of T2D and highlights the potential anti-diabetic effects of flavonoids and mechanisms of their actions.
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Affiliation(s)
- Hana Alkhalidy
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA.
- Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, Irbid 22110, Jordan.
| | - Yao Wang
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA.
| | - Dongmin Liu
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA.
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24
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Pipeleers D, De Mesmaeker I, Robert T, Van Hulle F. Heterogeneity in the Beta-Cell Population: a Guided Search Into Its Significance in Pancreas and in Implants. Curr Diab Rep 2017; 17:86. [PMID: 28812213 PMCID: PMC5557868 DOI: 10.1007/s11892-017-0925-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PURPOSE OF REVIEW Intercellular differences in function have since long been noticed in the pancreatic beta-cell population. Heterogeneity in cellular glucose responsiveness is considered of physiological and pathological relevance. The present review updates evidence for the physiologic significance of beta-cell heterogeneity in the pancreas. It also briefly discusses what this role would imply for beta-cell implants in diabetes. RECENT FINDINGS Over the past 3 years, functionally different beta cells have been related to mechanisms that may underlie their heterogeneity in the pancreas, such as the stage in their life cycle and the degree of their clustering to islets with varying vascularization. Markers were identified for detecting these subpopulations in tissues. The existence of a functional heterogeneity in the pancreatic beta-cell population is further supported. Views on its origin and methods for its analysis in pancreas and implants will help guide the search into its significance in beta-cell biology, pathology, and therapy.
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Affiliation(s)
- Daniel Pipeleers
- Diabetes Research Center, Brussels Free University-VUB, Laarbeeklaan 103, 1090, Brussels, Belgium.
| | - Ines De Mesmaeker
- Diabetes Research Center, Brussels Free University-VUB, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Thomas Robert
- Diabetes Research Center, Brussels Free University-VUB, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Freya Van Hulle
- Diabetes Research Center, Brussels Free University-VUB, Laarbeeklaan 103, 1090, Brussels, Belgium
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25
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Kawamori D, Shirakawa J, Liew CW, Hu J, Morioka T, Duttaroy A, Burkey B, Kulkarni RN. GLP-1 signalling compensates for impaired insulin signalling in regulating beta cell proliferation in βIRKO mice. Diabetologia 2017; 60:1442-1453. [PMID: 28526921 PMCID: PMC5508991 DOI: 10.1007/s00125-017-4303-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/18/2017] [Indexed: 01/08/2023]
Abstract
AIMS/HYPOTHESIS We aimed to investigate potential interactions between insulin and glucagon-like peptide (GLP)-1 signalling pathways in the regulation of beta cell-cycle dynamics in vivo, in the context of the therapeutic potential of GLP-1 to modulate impaired beta cell function. METHODS Beta cell-specific insulin receptor knockout (βIRKO) mice, which exhibit beta cell dysfunction and an age-dependent decrease in beta cell mass, were treated with the dipeptidyl peptidase-4 inhibitor vildagliptin. Following this, glucose homeostasis and beta cell proliferation were evaluated and underlying molecular mechanisms were investigated. RESULTS The sustained elevation in circulating GLP-1 levels, caused by treatment of the knockout mice with vildagliptin for 6 weeks, significantly improved glucose tolerance secondary to enhanced insulin secretion and proliferation of beta cells. Treating βIRKO beta cell lines with the GLP-1 analogue, exendin-4, promoted Akt phosphorylation and protein expression of cyclins A, D1 and E two- to threefold, in addition to cyclin D2. Pancreases from the vildagliptin-treated βIRKO mice exhibited increased cyclin D1 expression, while cyclin D2 expression was impaired. CONCLUSIONS/INTERPRETATION Activation of GLP-1 signalling compensates for impaired growth factor (insulin) signalling and enhances expression of cyclins to promote beta cell proliferation. Together, these data indicate the potential of GLP-1-related therapies to enhance beta cell proliferation and promote beneficial outcomes in models with dysfunctional beta cells.
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Affiliation(s)
- Dan Kawamori
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Room 410, One Joslin Place, Boston, MA, 02215, USA
- Department of Metabolic Medicine, Graduate School of Medicine, Osaka University, Osaka, Japan
- Medical Education Center, Faculty of Medicine, Osaka University, Osaka, Japan
| | - Jun Shirakawa
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Room 410, One Joslin Place, Boston, MA, 02215, USA
| | - Chong Wee Liew
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Room 410, One Joslin Place, Boston, MA, 02215, USA
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - Jiang Hu
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Room 410, One Joslin Place, Boston, MA, 02215, USA
| | - Tomoaki Morioka
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Room 410, One Joslin Place, Boston, MA, 02215, USA
- Department of Metabolism, Endocrinology and Molecular Medicine, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | - Alokesh Duttaroy
- Cardiovascular & Metabolic Diseases, Novartis Institutes for Biomedical Research, Inc., Cambridge, MA, USA
| | | | - Rohit N Kulkarni
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Room 410, One Joslin Place, Boston, MA, 02215, USA.
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
- Harvard Stem Cell Institute, Boston, MA, USA.
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26
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Sacaan AI, Thibault S, Hong M, Kondegowda NG, Nichols T, Li R, Rosselot C, Evering W, Fenutria R, Vitsky A, Brown T, Finkelstein M, Garcia-Ocaña A, Khan N, Stewart AF, Vasavada RC. CDK4/6 Inhibition on Glucose and Pancreatic Beta Cell Homeostasis in Young and Aged Rats. Mol Cancer Res 2017; 15:1531-1541. [DOI: 10.1158/1541-7786.mcr-17-0172] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 06/27/2017] [Accepted: 07/25/2017] [Indexed: 11/16/2022]
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Aamodt KI, Aramandla R, Brown JJ, Fiaschi-Taesch N, Wang P, Stewart AF, Brissova M, Powers AC. Development of a reliable automated screening system to identify small molecules and biologics that promote human β-cell regeneration. Am J Physiol Endocrinol Metab 2016; 311:E859-E868. [PMID: 27624103 PMCID: PMC5130356 DOI: 10.1152/ajpendo.00515.2015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 09/09/2016] [Indexed: 11/22/2022]
Abstract
Numerous compounds stimulate rodent β-cell proliferation; however, translating these findings to human β-cells remains a challenge. To examine human β-cell proliferation in response to such compounds, we developed a medium-throughput in vitro method of quantifying adult human β-cell proliferation markers. This method is based on high-content imaging of dispersed islet cells seeded in 384-well plates and automated cell counting that identifies fluorescently labeled β-cells with high specificity using both nuclear and cytoplasmic markers. β-Cells from each donor were assessed for their function and ability to enter the cell cycle by cotransduction with adenoviruses encoding cell cycle regulators cdk6 and cyclin D3. Using this approach, we tested 12 previously identified mitogens, including neurotransmitters, hormones, growth factors, and molecules, involved in adenosine and Tgf-1β signaling. Each compound was tested in a wide concentration range either in the presence of basal (5 mM) or high (11 mM) glucose. Treatment with the control compound harmine, a Dyrk1a inhibitor, led to a significant increase in Ki-67+ β-cells, whereas treatment with other compounds had limited to no effect on human β-cell proliferation. This new scalable approach reduces the time and effort required for sensitive and specific evaluation of human β-cell proliferation, thus allowing for increased testing of candidate human β-cell mitogens.
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Affiliation(s)
- Kristie I Aamodt
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Radhika Aramandla
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Judy J Brown
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Nathalie Fiaschi-Taesch
- Division of Endocrinology, Diabetes, and Bone Disease, Department of Medicine, Mount Sinai Medical Center, New York, New York; and
| | - Peng Wang
- Division of Endocrinology, Diabetes, and Bone Disease, Department of Medicine, Mount Sinai Medical Center, New York, New York; and
| | - Andrew F Stewart
- Division of Endocrinology, Diabetes, and Bone Disease, Department of Medicine, Mount Sinai Medical Center, New York, New York; and
| | - Marcela Brissova
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee;
| | - Alvin C Powers
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee
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28
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Jung HS, Kang YM, Park HS, Ahn BY, Lee H, Kim MJ, Jang JY, Kim SW. Senp2 expression was induced by chronic glucose stimulation in INS1 cells, and it was required for the associated induction of Ccnd1 and Mafa. Islets 2016; 8:207-216. [PMID: 27644314 PMCID: PMC5161141 DOI: 10.1080/19382014.2016.1235677] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Post-translational modification by bonding of small ubiquitin-like modifier (SUMO) peptides influences various cellular functions, and is regulated by SUMO-specific proteases (SENPs). Several proteins have been suggested to have diverse impact on insulin synthesis and secretion through SUMO modification in β cells. However, the role of SUMO modification in β cell mass has not been established. Here, we examined the changes in expression of Senp in INS1 cells and pancreatic islets under diabetes-relevant stress conditions and associated changes in β cell mass. Treatment with 25 mM glucose for 72 h induced Senp2 mRNA expression but not that of Senp1 in INS1 cells. Immunohistochemical staining with anti-SENP2 antibody on human pancreas sections revealed that SENP2 was localized in the nucleus. Moreover, in a patient with type 2 diabetes, SENP2 levels were enhanced, especially in the cytoplasm. Senp2 cytoplasmic levels were also increased in islet cells in obese diabetic mice. Cell number peaked earlier in INS1 cells cultured in high-glucose conditions compared to those cultured in control media. This finding was associated with increased Ccnd1 mRNA expression in high-glucose conditions, and siRNA-mediated Senp2 suppression abrogated it. Mafa expression, unlike Pdx1, was also dependent on Senp2 expression during high-glucose conditions. In conclusion, Senp2 may play a role in β cell mass in response to chronic high-glucose through Cyclin D1 and Mafa.
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Affiliation(s)
- Hye Seung Jung
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
- Innovative Research Institute for Cell Therapy, Seoul, Republic of Korea
- CONTACT Hye Seung Jung Department of Internal Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Yu Mi Kang
- Innovative Research Institute for Cell Therapy, Seoul, Republic of Korea
| | - Ho Seon Park
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Byung Yong Ahn
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hakmo Lee
- Innovative Research Institute for Cell Therapy, Seoul, Republic of Korea
| | - Min Joo Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jin Young Jang
- Department of Surgery, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sun-Whe Kim
- Department of Surgery, Seoul National University College of Medicine, Seoul, Republic of Korea
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29
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Tramutola A, Arena A, Cini C, Butterfield DA, Barone E. Modulation of GLP-1 signaling as a novel therapeutic approach in the treatment of Alzheimer’s disease pathology. Expert Rev Neurother 2016; 17:59-75. [DOI: 10.1080/14737175.2017.1246183] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Antonella Tramutola
- Department of Biochemical Sciences ‘A. Rossi-Fanelli’, Sapienza University of Rome, Roma, Italy
| | - Andrea Arena
- Department of Biochemical Sciences ‘A. Rossi-Fanelli’, Sapienza University of Rome, Roma, Italy
| | - Chiara Cini
- Department of Biochemical Sciences ‘A. Rossi-Fanelli’, Sapienza University of Rome, Roma, Italy
| | - D. Allan Butterfield
- Department of Chemistry and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Eugenio Barone
- Department of Biochemical Sciences ‘A. Rossi-Fanelli’, Sapienza University of Rome, Roma, Italy
- Universidad Autónoma de Chile, Instituto de Ciencias Biomédicas, Facultad de Salud, Santiago, Chile
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Abstract
Carbohydrate, lipid, and protein metabolism are largely controlled by the interplay of various hormones, which includes those secreted by the pancreatic islets of Langerhans. While typically representing only 1% to 2% of the total pancreatic mass, the islets have a remarkable ability to adapt to disparate situations demanding a change in hormone release, such as peripheral insulin resistance. There are many different routes to the onset of insulin resistance, including obesity, lipodystrophy, glucocorticoid excess, and the chronic usage of atypical antipsychotic drugs. All of these situations are coupled to an increase in pancreatic islet size, often with a corresponding increase in insulin production. These adaptive responses within the islets are ultimately intended to maintain glycemic control and to promote macronutrient homeostasis during times of stress. Herein, we review the consequences of specific metabolic trauma that lead to insulin resistance and the corresponding adaptive alterations within the pancreatic islets.
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Affiliation(s)
- Susan J. Burke
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808
| | - Michael D. Karlstad
- Department of Surgery, Graduate School of Medicine, University of Tennessee Health Science Center, Knoxville, TN 37920
| | - J. Jason Collier
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808
- Department of Surgery, Graduate School of Medicine, University of Tennessee Health Science Center, Knoxville, TN 37920
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31
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Zhao Y, Shi K, Su X, Xie L, Yan Y. Microcystin-LR induces dysfunction of insulin secretion in rat insulinoma (INS-1) cells: Implications for diabetes mellitus. JOURNAL OF HAZARDOUS MATERIALS 2016; 314:11-21. [PMID: 27107231 DOI: 10.1016/j.jhazmat.2016.04.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 03/26/2016] [Accepted: 04/09/2016] [Indexed: 06/05/2023]
Abstract
Microcystins (MCs) are the most frequent cyanobacterial toxins observed in freshwater systems. Accumulating evidence suggests that MCs pose a serious threat to public health. However, the contributions of the exposure of MCs to the occurrence of human diseases remain largely unknown. This study provides the evidence of the effects of MC-LR on pancreatic β-cell function through the exposure of rat insulinoma (INS-1) cells to 0, 10, 20, or 40μM MC-LR for 72h and explores the underlying molecular mechanisms. Our results demonstrate that exposure to MC-LR for 72h suppresses cell viability, disturbs glucose-stimulated insulin secretion (GSIS), and decreases the expression of insulin protein. Moreover, MC-LR disrupts the cell cycle distribution and increases cell apoptosis at 20 or 40μM for 72h, respectively, indicating that the β-cell mass would be decreased by MC-LR exposure. A transcriptomic analysis revealed several key genes (e.g., Pdx-1, Neurod1, and Abcc8) involved in insulin secretion are significantly differentially expressed in INS-1 cells in response to MC-LR exposure. In addition, several signal transduction pathways associated with diabetes (e.g., type 1 and 2 diabetes) were also identified compared with the control cells. We recommend that MC be considered as a new environmental factor that promotes diabetes development. The identified key genes or pathways may potentially contribute to the future therapies in the environmental contaminants induced β-cell damage.
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Affiliation(s)
- Yanyan Zhao
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China.
| | - Kun Shi
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China
| | - Xiaomei Su
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China
| | - Liqiang Xie
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China.
| | - Yunjun Yan
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, PR China
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32
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Kong Y, Sharma RB, Nwosu BU, Alonso LC. Islet biology, the CDKN2A/B locus and type 2 diabetes risk. Diabetologia 2016; 59:1579-93. [PMID: 27155872 PMCID: PMC4930689 DOI: 10.1007/s00125-016-3967-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 03/29/2016] [Indexed: 02/06/2023]
Abstract
Type 2 diabetes, fuelled by the obesity epidemic, is an escalating worldwide cause of personal hardship and public cost. Diabetes incidence increases with age, and many studies link the classic senescence and ageing protein p16(INK4A) to diabetes pathophysiology via pancreatic islet biology. Genome-wide association studies (GWASs) have unequivocally linked the CDKN2A/B locus, which encodes p16 inhibitor of cyclin-dependent kinase (p16(INK4A)) and three other gene products, p14 alternate reading frame (p14(ARF)), p15(INK4B) and antisense non-coding RNA in the INK4 locus (ANRIL), with human diabetes risk. However, the mechanism by which the CDKN2A/B locus influences diabetes risk remains uncertain. Here, we weigh the evidence that CDKN2A/B polymorphisms impact metabolic health via islet biology vs effects in other tissues. Structured in a bedside-to-bench-to-bedside approach, we begin with a summary of the evidence that the CDKN2A/B locus impacts diabetes risk and a brief review of the basic biology of CDKN2A/B gene products. The main emphasis of this work is an in-depth look at the nuanced roles that CDKN2A/B gene products and related proteins play in the regulation of beta cell mass, proliferation and insulin secretory function, as well as roles in other metabolic tissues. We finish with a synthesis of basic biology and clinical observations, incorporating human physiology data. We conclude that it is likely that the CDKN2A/B locus influences diabetes risk through both islet and non-islet mechanisms.
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Affiliation(s)
- Yahui Kong
- AS7-2047, Division of Diabetes, Department of Medicine, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Rohit B Sharma
- AS7-2047, Division of Diabetes, Department of Medicine, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Benjamin U Nwosu
- Division of Endocrinology, Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA, USA
| | - Laura C Alonso
- AS7-2047, Division of Diabetes, Department of Medicine, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605, USA.
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33
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Kim M, Kim DK, Cha YS. Black Adzuki Bean (Vigna angularis) Extract Protects Pancreatic β Cells and Improves Glucose Tolerance in C57BL/6J Mice Fed a High-Fat Diet. J Med Food 2016; 19:442-9. [DOI: 10.1089/jmf.2015.3598] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Mina Kim
- Department of Food Science and Human Nutrition, and Research Institute of Human Ecology, Chonbuk National University, Jeonju, Korea
| | - Dae Keun Kim
- College of Pharmacy, Woosuk University, Jeonju, Korea
| | - Youn-Soo Cha
- Department of Food Science and Human Nutrition, and Research Institute of Human Ecology, Chonbuk National University, Jeonju, Korea
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El-Badawy A, El-Badri N. The cell cycle as a brake for β-cell regeneration from embryonic stem cells. Stem Cell Res Ther 2016; 7:9. [PMID: 26759123 PMCID: PMC4711007 DOI: 10.1186/s13287-015-0274-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The generation of insulin-producing β cells from stem cells in vitro provides a promising source of cells for cell transplantation therapy in diabetes. However, insulin-producing cells generated from human stem cells show deficiency in many functional characteristics compared with pancreatic β cells. Recent reports have shown molecular ties between the cell cycle and the differentiation mechanism of embryonic stem (ES) cells, assuming that cell fate decisions are controlled by the cell cycle machinery. Both β cells and ES cells possess unique cell cycle machinery yet with significant contrasts. In this review, we compare the cell cycle control mechanisms in both ES cells and β cells, and highlight the fundamental differences between pluripotent cells of embryonic origin and differentiated β cells. Through critical analysis of the differences of the cell cycle between these two cell types, we propose that the cell cycle of ES cells may act as a brake for β-cell regeneration. Based on these differences, we discuss the potential of modulating the cell cycle of ES cells for the large-scale generation of functionally mature β cells in vitro. Further understanding of the factors that modulate the ES cell cycle will lead to new approaches to enhance the production of functional mature insulin-producing cells, and yield a reliable system to generate bona fide β cells in vitro.
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Affiliation(s)
- Ahmed El-Badawy
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, Sheikh Zayed District, 12588, 6th of October City, Giza, Egypt
| | - Nagwa El-Badri
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, Sheikh Zayed District, 12588, 6th of October City, Giza, Egypt.
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35
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Bedinger DH, Adams SH. Metabolic, anabolic, and mitogenic insulin responses: A tissue-specific perspective for insulin receptor activators. Mol Cell Endocrinol 2015; 415:143-56. [PMID: 26277398 DOI: 10.1016/j.mce.2015.08.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 08/05/2015] [Accepted: 08/09/2015] [Indexed: 12/17/2022]
Abstract
Insulin acts as the major regulator of the fasting-to-fed metabolic transition by altering substrate metabolism, promoting energy storage, and helping activate protein synthesis. In addition to its glucoregulatory and other metabolic properties, insulin can also act as a growth factor. The metabolic and mitogenic responses to insulin are regulated by divergent post-receptor signaling mechanisms downstream from the activated insulin receptor (IR). However, the anabolic and growth-promoting properties of insulin require tissue-specific inter-relationships between the two pathways, and the nature and scope of insulin-regulated processes vary greatly across tissues. Understanding the nuances of this interplay between metabolic and growth-regulating properties of insulin would have important implications for development of novel insulin and IR modulator therapies that stimulate insulin receptor activation in both pathway- and tissue-specific manners. This review will provide a unique perspective focusing on the roles of "metabolic" and "mitogenic" actions of insulin signaling in various tissues, and how these networks should be considered when evaluating selective pharmacologic approaches to prevent or treat metabolic disease.
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Affiliation(s)
| | - Sean H Adams
- Arkansas Children's Nutrition Center and University of Arkansas for Medical Sciences, Department of Pediatrics, Little Rock, AR, USA
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36
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Tiwari S, Roel C, Wills R, Casinelli G, Tanwir M, Takane KK, Fiaschi-Taesch NM. Early and Late G1/S Cyclins and Cdks Act Complementarily to Enhance Authentic Human β-Cell Proliferation and Expansion. Diabetes 2015; 64:3485-98. [PMID: 26159177 PMCID: PMC4876788 DOI: 10.2337/db14-1885] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 06/20/2015] [Indexed: 12/20/2022]
Abstract
β-Cell regeneration is a key goal of diabetes research. Progression through the cell cycle is associated with retinoblastoma protein (pRb) inactivation via sequential phosphorylation by the "early" cyclins and cyclin-dependent kinases (cdks) (d-cyclins cdk4/6) and the "late" cyclins and cdks (cyclin A/E and cdk1/2). In β-cells, activation of either early or late G1/S cyclins and/or cdks is an efficient approach to induce cycle entry, but it is unknown whether the combined expression of early and late cyclins and cdks might have synergistic or additive effects. Thus, we explored whether a combination of both early and late cyclins and cdks might more effectively drive human β-cell cell cycle entry than either group alone. We also sought to determine whether authentic replication with the expansion of adult human β-cells could be demonstrated. Late cyclins and cdks do not traffic in response to the induction of replication by early cyclins and cdks in human β-cells but are capable of nuclear translocation when overexpressed. Early plus late cyclins and cdks, acting via pRb phosphorylation on distinct residues, complementarily induce greater proliferation in human β-cells than either group alone. Importantly, the combination of early and late cyclins and cdks clearly increased human β-cell numbers in vitro. These findings provide additional insight into human β-cell expansion. They also provide a novel tool for assessing β-cell expansion in vitro.
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Affiliation(s)
- Shiwani Tiwari
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Chris Roel
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Rachel Wills
- Division of Endocrinology and Metabolism, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Gabriella Casinelli
- Division of Endocrinology and Metabolism, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Mansoor Tanwir
- Division of Endocrinology and Metabolism, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Karen K Takane
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Nathalie M Fiaschi-Taesch
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY Division of Endocrinology and Metabolism, University of Pittsburgh School of Medicine, Pittsburgh, PA
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Abstract
OBJECTIVES In injury conditions, myofibroblasts are induced to lay down matrix proteins and support the repair process. In this study, we investigated the role of myofibroblasts, particularly stellate cells, in the growth and regeneration of pancreatic β cells. METHODS We used both in vitro and in vivo approaches to address whether stellate cells may promote the growth of β cells. RESULTS Our experiments demonstrated that activated stellate cells support the proliferation of β cells in vitro. In vivo, mesenchymals surrounding the pancreatic islets are activated (induced to proliferate) in the islet regeneration model of Pten null mice. These mesenchymals display markers of pancreatic stellate cells, such as desmin and to a lesser extent, smooth muscle actin α. We have shown previously that targeted β-cell deletion of Pten lead to a significant increase in total islet mass. This phenotype was accompanied by an increase in peri-islet mitotic activity, particularly in islets injured by streptozotocin, a β cell-specific toxin. CONCLUSIONS Together with the in vitro observations, our data, here, suggest that that these mesenchymal cells may support the regeneration of the islets. Identifying how the communication occurs may provide clinically relevant mechanism for inducing β-cell regeneration.
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Richardson T, Kumta PN, Banerjee I. Alginate encapsulation of human embryonic stem cells to enhance directed differentiation to pancreatic islet-like cells. Tissue Eng Part A 2015; 20:3198-211. [PMID: 24881778 DOI: 10.1089/ten.tea.2013.0659] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The pluripotent property of human embryonic stem cells (hESCs) makes them attractive for treatment of degenerative diseases such as diabetes. We have developed a stage-wise directed differentiation protocol to produce alginate-encapsulated islet-like cells derived from hESCs, which can be directly implanted for diabetes therapy. The advantage of alginate encapsulation lies in its capability to immunoisolate, along with the added possibility of scalable culture. We have evaluated the possibility of encapsulating hESCs at different stages of differentiation. Encapsulation of predifferentiated cells resulted in insufficient cellular yield and differentiation. On the other hand, encapsulation of undifferentiated hESCs followed by differentiation induction upon encapsulation resulted in the highest viability and differentiation. More striking was that alginate encapsulation resulted in a much stronger differentiation compared to parallel two-dimensional cultures, resulting in 20-fold increase in c-peptide protein synthesis. To elucidate the mechanism contributing to encapsulation-mediated enhancement in hESC maturation, investigation of the signaling pathways revealed interesting insight. While the phospho-protein levels of all the tested signaling molecules were lower under encapsulation, the ratio of pSMAD/pAKT was significantly higher, indicating a more efficient signal transduction under encapsulation. These results clearly demonstrate that alginate encapsulation of hESCs and differentiation to islet-cell types provides a potentially translatable treatment option for type 1 diabetes.
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Affiliation(s)
- Thomas Richardson
- 1 Department of Chemical Engineering, University of Pittsburgh , Pittsburgh, Pennsylvania
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39
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Aldosterone induces clonal β-cell failure through glucocorticoid receptor. Sci Rep 2015; 5:13215. [PMID: 26287126 PMCID: PMC4541150 DOI: 10.1038/srep13215] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 07/20/2015] [Indexed: 12/21/2022] Open
Abstract
Aldosterone excess causes insulin resistance in peripheral tissues and directly impairs the function of clonal β-cell. The aim of this study was to investigate the molecular mechanisms involved in the aldosterone-induced impairment of clonal β-cells. As expected, aldosterone induced apoptosis and β-cell dysfunction, including impairment of insulin synthesis and secretion, which were reversed by Glucocorticoid receptor (GR) antagonists or GR-specific siRNA. However, mineralocorticoid receptor (MR) antagonists or MR-specific siRNA had no effect on impairment of clonal β-cells induced by aldosterone. Besides, aldosterone significantly decreased expression and activity of MafA, while activated JNK and p38 MAPK in a GR-dependent manner. In addition, JNK inhibitors (SP600125) and/or p38 inhibitors (SB203580) could abolish the effect of aldosterone on MafA expression and activity. Importantly, overexpression of JNK1 or p38 reversed the protective effect of a GR antagonist on the decrease of MafA expression and activity. Furthermore, aldosterone inhibits MafA expression at the transcriptional and post-transcriptional level through activation of JNK and p38, respectively. Consequently, overexpression of MafA increased synthesis and secretion of insulin, and decreased apoptosis in clonal β-cells exposed to aldosterone. These findings identified aldosterone as an inducer of clonal β-cell failure that operates through the GR-MAPK-MafA signaling pathway.
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Oh YS, Shin S, Li HY, Park EY, Lee SM, Choi CS, Lim Y, Jung HS, Jun HS. Betacellulin ameliorates hyperglycemia in obese diabetic db/db mice. J Mol Med (Berl) 2015; 93:1235-45. [PMID: 26070436 DOI: 10.1007/s00109-015-1303-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 04/20/2015] [Accepted: 05/20/2015] [Indexed: 01/08/2023]
Abstract
UNLABELLED We found that administration of a recombinant adenovirus (rAd) expressing betacellulin (BTC) into obese diabetic db/db mice ameliorated hyperglycemia. Exogenous glucose clearance was significantly improved, and serum insulin levels were significantly higher in rAd-BTC-treated mice than rAd-β-gal-treated control mice. rAd-BTC treatment increased insulin/bromodeoxyuridine double-positive cells in the islets, and islets from rAd-BTC-treated mice exhibited a significant increase in the level of G1-S phase-related cyclins as compared with control mice. In addition, BTC treatment increased messenger RNA (mRNA) and protein levels of these cyclins and cyclin-dependent kinases in MIN-6 cells. BTC treatment induced intracellular Ca(2+) levels through phospholipase C-γ1 activation, and upregulated calcineurin B (CnB1) levels as well as calcineurin activity. Upregulation of CnB1 by BTC treatment was observed in isolated islet cells from db/db mice. When treated with CnB1 small interfering RNA (siRNA) in MIN-6 cells and isolated islets, induction of cell cycle regulators by BTC treatment was blocked and consequently reduced BTC-induced cell viability. As well as BTC's effects on cell survival and insulin secretion, our findings demonstrate a novel pathway by which BTC controls beta-cell regeneration in the obese diabetic condition by regulating G1-S phase cell cycle expression through Ca(2+) signaling pathways. KEY MESSAGES Administration of BTC to db/db mice results in amelioration of hyperglycemia. BTC stimulates beta-cell proliferation in db/db mice. Ca(2+) signaling was involved in BTC-induced beta-cell proliferation. BTC has an anti-apoptotic effect and potentiates glucose-stimulated insulin secretion.
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Affiliation(s)
- Yoon Sin Oh
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon, Korea.,Gachon Medical Research Institute, Gil Hospital, Incheon, Korea
| | | | - Hui Ying Li
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon, Korea.,College of Pharmacy, Gachon University, Incheon, Korea
| | - Eun-Young Park
- College of Pharmacy, Mokpo National University, Jeonnam, Korea
| | - Song Mi Lee
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon, Korea.,College of Pharmacy, Gachon University, Incheon, Korea
| | - Cheol Soo Choi
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon, Korea.,Gachon Medical Research Institute, Gil Hospital, Incheon, Korea
| | - Yong Lim
- Department of Microbiology, Chosun University College of Medicine, Chonnam, Korea
| | - Hye Seung Jung
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Hee-Sook Jun
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon, Korea. .,Gachon Medical Research Institute, Gil Hospital, Incheon, Korea. .,College of Pharmacy, Gachon University, Incheon, Korea.
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Mosa RMH, Zhang Z, Shao R, Deng C, Chen J, Chen C. Implications of ghrelin and hexarelin in diabetes and diabetes-associated heart diseases. Endocrine 2015; 49:307-23. [PMID: 25645463 DOI: 10.1007/s12020-015-0531-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 01/12/2015] [Indexed: 02/07/2023]
Abstract
Ghrelin and its synthetic analog hexarelin are specific ligands of growth hormone secretagogue (GHS) receptor. GHS have strong growth hormone-releasing effect and other neuroendocrine activities such as stimulatory effects on prolactin and adrenocorticotropic hormone secretion. Recently, several studies have reported other beneficial functions of GHS that are independent of GH. Ghrelin and hexarelin, for examples, have been shown to exert GH-independent cardiovascular activity. Hexarelin has been reported to regulate peroxisome proliferator-activated receptor gamma (PPAR-γ) in macrophages and adipocytes. PPAR-γ is an important regulator of adipogenesis, lipid metabolism, and insulin sensitization. Ghrelin also shows protective effects on beta cells against lipotoxicity through activation of phosphatidylinositol-3 kinase/protein kinase B, c-Jun N-terminal kinase (JNK) inhibition, and nuclear exclusion of forkhead box protein O1. Acylated ghrelin (AG) and unacylated ghrelin (UAG) administration reduces glucose levels and increases insulin-producing beta cell number, and insulin secretion in pancreatectomized rats and in newborn rats treated with streptozotocin, suggesting a possible role of GHS in pancreatic regeneration. Therefore, the discovery of GHS has opened many new perspectives in endocrine, metabolic, and cardiovascular research areas, suggesting the possible therapeutic application in diabetes and diabetic complications especially diabetic cardiomyopathy. Here, we review the physiological roles of ghrelin and hexarelin in the protection and regeneration of beta cells and their roles in the regulation of insulin release, glucose, and fat metabolism and present their potential therapeutic effects in the treatment of diabetes and diabetic-associated heart diseases.
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Wang P, Fiaschi-Taesch NM, Vasavada RC, Scott DK, García-Ocaña A, Stewart AF. Diabetes mellitus--advances and challenges in human β-cell proliferation. Nat Rev Endocrinol 2015; 11:201-12. [PMID: 25687999 DOI: 10.1038/nrendo.2015.9] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The treatment of diabetes mellitus represents one of the greatest medical challenges of our era. Diabetes results from a deficiency or functional impairment of insulin-producing β cells, alone or in combination with insulin resistance. It logically follows that the replacement or regeneration of β cells should reverse the progression of diabetes and, indeed, this seems to be the case in humans and rodents. This concept has prompted attempts in many laboratories to create new human β cells using stem-cell strategies to transdifferentiate or reprogramme non-β cells into β cells or to discover small molecules or other compounds that can induce proliferation of human β cells. This latter approach has shown promise, but has also proven particularly challenging to implement. In this Review, we discuss the physiology of normal human β-cell replication, the molecular mechanisms that regulate the cell cycle in human β cells, the upstream intracellular signalling pathways that connect them to cell surface receptors on β cells, the epigenetic mechanisms that control human β-cell proliferation and unbiased approaches for discovering novel molecules that can drive human β-cell proliferation. Finally, we discuss the potential and challenges of implementing strategies that replace or regenerate β cells.
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Affiliation(s)
- Peng Wang
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Nathalie M Fiaschi-Taesch
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Rupangi C Vasavada
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Donald K Scott
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Adolfo García-Ocaña
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Andrew F Stewart
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
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Jiménez-Palomares M, López-Acosta JF, Villa-Pérez P, Moreno-Amador JL, Muñoz-Barrera J, Fernández-Luis S, Heras-Pozas B, Perdomo G, Bernal-Mizrachi E, Cózar-Castellano I. Cyclin C stimulates β-cell proliferation in rat and human pancreatic β-cells. Am J Physiol Endocrinol Metab 2015; 308:E450-9. [PMID: 25564474 PMCID: PMC4360017 DOI: 10.1152/ajpendo.00260.2014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Activation of pancreatic β-cell proliferation has been proposed as an approach to replace reduced functional β-cell mass in diabetes. Quiescent fibroblasts exit from G0 (quiescence) to G1 through pRb phosphorylation mediated by cyclin C/cdk3 complexes. Overexpression of cyclin D1, D2, D3, or cyclin E induces pancreatic β-cell proliferation. We hypothesized that cyclin C overexpression would induce β-cell proliferation through G0 exit, thus being a potential therapeutic target to recover functional β-cell mass. We used isolated rat and human islets transduced with adenovirus expressing cyclin C. We measured multiple markers of proliferation: [(3)H]thymidine incorporation, BrdU incorporation and staining, and Ki67 staining. Furthermore, we detected β-cell death by TUNEL, β-cell differentiation by RT-PCR, and β-cell function by glucose-stimulated insulin secretion. Interestingly, we have found that cyclin C increases rat and human β-cell proliferation. This augmented proliferation did not induce β-cell death, dedifferentiation, or dysfunction in rat or human islets. Our results indicate that cyclin C is a potential target for inducing β-cell regeneration.
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Affiliation(s)
| | | | - Pablo Villa-Pérez
- Instituto de Genética y Biología Molecular, Universidad de Valladolid-CSIC, Valladolid, Spain
| | | | - Jennifer Muñoz-Barrera
- Instituto de Genética y Biología Molecular, Universidad de Valladolid-CSIC, Valladolid, Spain
| | - Sara Fernández-Luis
- Instituto de Genética y Biología Molecular, Universidad de Valladolid-CSIC, Valladolid, Spain
| | - Blanca Heras-Pozas
- Instituto de Genética y Biología Molecular, Universidad de Valladolid-CSIC, Valladolid, Spain
| | - Germán Perdomo
- Departamento de Química Inorgánica, Orgánica y Bioquímica, Universidad de Castilla La Mancha, Spain
| | - Ernesto Bernal-Mizrachi
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan
| | - Irene Cózar-Castellano
- Instituto de Genética y Biología Molecular, Universidad de Valladolid-CSIC, Valladolid, Spain;
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Molecular and immunohistochemical effects of metformin in a rat model of type 2 diabetes mellitus. Exp Ther Med 2015; 9:1921-1930. [PMID: 26136915 DOI: 10.3892/etm.2015.2354] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 03/05/2015] [Indexed: 12/14/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a serious health issue worldwide. The disease is characterized by insulin resistance (IR), which leads to dyslipidemia and alterations in the expression levels of a number of genes. Metformin is the standard treatment for T2DM; however, the exact mechanism underlying metformin regulation is not fully understood. The aim of the present study was to investigate the effects of metformin on serum lipid profiles and the expression levels of various genes that are associated with IR, as well as the histopathological changes in the liver and pancreas. A T2DM rat model was established by feeding the rats a high-fat diet for 4 weeks, combined with a dose of streptozotocin (35 mg/kg body weight). Following the successful induction of T2DM, metformin was administered orally (400 mg/kg/day) for 4 weeks. The results indicated that metformin improved the symptoms of IR by normalizing the serum lipid profiles in the diabetic rats. Furthermore, metformin upregulated the expression of insulin receptors and genes associated with lipid metabolism, including acyl-CoA oxidase, carnitine palmitoyl transferase-1 and peroxisome proliferator activated receptor-α. In addition, treatment with metformin downregulated the expression levels of fetuin-A and retinol binding protein-4 (RBP-4), while normalizing the expression of perilipin that had been reduced in the T2DM rats. Metformin administration induced regenerative changes in the hepatocyte cytoplasm and parenchyma. In the pancreas, treatment with metformin was shown to induce positive signaling for insulin and the regeneration of pancreatic β cells. In summary, metformin treatment ameliorated a number of the harmful effects associated with T2DM via the modulation of the expression levels of fetuin-A, RBP-4, perilipin and various genes associated with lipid metabolism, resulting in regenerative changes in the liver and pancreatic cells.
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Khadra A, Schnell S. Development, growth and maintenance of β-cell mass: models are also part of the story. Mol Aspects Med 2015; 42:78-90. [PMID: 25720614 DOI: 10.1016/j.mam.2015.01.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 01/26/2015] [Accepted: 01/26/2015] [Indexed: 01/09/2023]
Abstract
Pancreatic β-cells in the islets of Langerhans play a crucial role in regulating glucose homeostasis in the circulation. Loss of β-cell mass or function due to environmental, genetic and immunological factors leads to the manifestation of diabetes mellitus. The mechanisms regulating the dynamics of pancreatic β-cell mass during normal development and diabetes progression are complex. To fully unravel such complexity, experimental and clinical approaches need to be combined with mathematical and computational models. In the natural sciences, mathematical and computational models have aided the identification of key mechanisms underlying the behavior of systems comprising multiple interacting components. A number of mathematical and computational models have been proposed to explain the development, growth and death of pancreatic β-cells. In this review, we discuss some of these models and how their predictions provide novel insight into the mechanisms controlling β-cell mass during normal development and diabetes progression. Lastly, we discuss a handful of the major open questions in the field.
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Affiliation(s)
- Anmar Khadra
- Department of Physiology, McGill University, McIntyre Medical Building, 3655 Promenade Sir William Osler, Montreal, Quebec H3G 1Y6, Canada
| | - Santiago Schnell
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan 48105, USA; Department of Computational Medicine & Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan 48105, USA; Brehm Center for Diabetes Research, University of Michigan Medical School, Ann Arbor, Michigan 48105, USA.
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Alkhalidy H, Moore W, Zhang Y, McMillan R, Wang A, Ali M, Suh KS, Zhen W, Cheng Z, Jia Z, Hulver M, Liu D. Small Molecule Kaempferol Promotes Insulin Sensitivity and Preserved Pancreatic β -Cell Mass in Middle-Aged Obese Diabetic Mice. J Diabetes Res 2015; 2015:532984. [PMID: 26064984 PMCID: PMC4439495 DOI: 10.1155/2015/532984] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 04/09/2015] [Accepted: 04/20/2015] [Indexed: 12/20/2022] Open
Abstract
Insulin resistance and a progressive decline in functional β-cell mass are hallmarks of developing type 2 diabetes (T2D). Thus, searching for natural, low-cost compounds to target these two defects could be a promising strategy to prevent the pathogenesis of T2D. Here, we show that dietary intake of flavonol kaempferol (0.05% in the diet) significantly ameliorated hyperglycemia, hyperinsulinemia, and circulating lipid profile, which were associated with the improved peripheral insulin sensitivity in middle-aged obese mice fed a high-fat (HF) diet. Kaempferol treatment reversed HF diet impaired glucose transport-4 (Glut4) and AMP-dependent protein kinase (AMPK) expression in both muscle and adipose tissues from obese mice. In vitro, kaempferol increased lipolysis and prevented high fatty acid-impaired glucose uptake, glycogen synthesis, AMPK activity, and Glut4 expression in skeletal muscle cells. Using another mouse model of T2D generated by HF diet feeding and low doses of streptozotocin injection, we found that kaempferol treatment significantly improved hyperglycemia, glucose tolerance, and blood insulin levels in obese diabetic mice, which are associated with the improved islet β-cell mass. These results demonstrate that kaempferol may be a naturally occurring anti-diabetic agent by improving peripheral insulin sensitivity and protecting against pancreatic β-cell dysfunction.
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Affiliation(s)
- Hana Alkhalidy
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - William Moore
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Yanling Zhang
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Ryan McMillan
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
- The Metabolic Phenotyping Core, Virginia Tech, Blacksburg, VA 24061, USA
| | - Aihua Wang
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Mostafa Ali
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Kyung-Shin Suh
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Wei Zhen
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Zhiyong Cheng
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Zhenquan Jia
- Department of Biology, The University of North Carolina at Greensboro, Greensboro, NC 27412, USA
| | - Matthew Hulver
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Dongmin Liu
- Department of Human Nutrition, Foods & Exercise, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
- *Dongmin Liu:
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Alejandro EU, Gregg B, Blandino-Rosano M, Cras-Méneur C, Bernal-Mizrachi E. Natural history of β-cell adaptation and failure in type 2 diabetes. Mol Aspects Med 2014; 42:19-41. [PMID: 25542976 DOI: 10.1016/j.mam.2014.12.002] [Citation(s) in RCA: 156] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 11/04/2014] [Accepted: 12/05/2014] [Indexed: 02/07/2023]
Abstract
Type 2 diabetes mellitus (T2D) is a complex disease characterized by β-cell failure in the setting of insulin resistance. The current evidence suggests that genetic predisposition, and environmental factors can impair the capacity of the β-cells to respond to insulin resistance and ultimately lead to their failure. However, genetic studies have demonstrated that known variants account for less than 10% of the overall estimated T2D risk, suggesting that additional unidentified factors contribute to susceptibility of this disease. In this review, we will discuss the different stages that contribute to the development of β-cell failure in T2D. We divide the natural history of this process in three major stages: susceptibility, β-cell adaptation and β-cell failure, and provide an overview of the molecular mechanisms involved. Further research into mechanisms will reveal key modulators of β-cell failure and thus identify possible novel therapeutic targets and potential interventions to protect against β-cell failure.
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Affiliation(s)
- Emilyn U Alejandro
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, MI, USA
| | - Brigid Gregg
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Manuel Blandino-Rosano
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, MI, USA
| | - Corentin Cras-Méneur
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, MI, USA
| | - Ernesto Bernal-Mizrachi
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, MI, USA; VA Ann Arbor Healthcare System, Ann Arbor, MI, USA.
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Bruun C, Christensen GL, Jacobsen MLB, Kanstrup MB, Jensen PR, Fjordvang H, Mandrup-Poulsen T, Billestrup N. Inhibition of beta cell growth and function by bone morphogenetic proteins. Diabetologia 2014; 57:2546-54. [PMID: 25260823 DOI: 10.1007/s00125-014-3384-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 09/02/2014] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS Impairment of beta cell mass and function is evident in both type 1 and type 2 diabetes. In healthy physiological conditions pancreatic beta cells adapt to the body's increasing insulin requirements by proliferation and improved function. We hypothesised that during the development of diabetes, there is an increase in the expression of inhibitory factors that prevent the beta cells from adapting to the increased need for insulin. We evaluated the effects of bone morphogenetic protein (BMP) 2 and -4 on beta cells. METHODS The effects of BMP2 and -4 on beta cell proliferation, apoptosis, gene expression and insulin release were studied in isolated islets of Langerhans from rats, mice and humans. The expression of BMPs was analysed by immunocytochemistry and real-time PCR. The role of endogenous BMP was investigated using a soluble and neutralising form of the BMP receptor 1A. RESULTS BMP2 and -4 were found to inhibit basal as well as growth factor-stimulated proliferation of primary beta cells from rats and mice. Bmp2 and Bmp4 mRNA and protein were expressed in islets and regulated by inflammatory cytokines. Neutralisation of endogenous BMP activity resulted in enhanced proliferation of rodent beta cells. The expression of Id mRNAs was induced by BMP4 in rat and human islets. Finally, glucose-induced insulin secretion was significantly impaired in rodent and human islets pre-treated with BMP4, and inhibition of BMP activity resulted in enhanced insulin release. CONCLUSIONS/INTERPRETATION These data show that BMP2 and -4 exert inhibitory actions on beta cells in vitro and suggest that BMPs exert regulatory roles of beta cell growth and function.
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Manyes L, Arribas M, Gomez C, Calzada N, Fernandez-Medarde A, Santos E. Transcriptional profiling reveals functional links between RasGrf1 and Pttg1 in pancreatic beta cells. BMC Genomics 2014; 15:1019. [PMID: 25421944 PMCID: PMC4301450 DOI: 10.1186/1471-2164-15-1019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 11/06/2014] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Our prior characterization of RasGrf1 deficient mice uncovered significant defects in pancreatic islet count and size as well as beta cell development and signaling function, raising question about the mechanisms linking RasGrf1 to the generation of those "pancreatic" phenotypes. RESULTS Here, we compared the transcriptional profile of highly purified pancreatic islets from RasGrf1 KO mice to that of WT control animals using commercial oligonucleotide microarrays. RasGrf1 elimination resulted in differential gene expression of numerous components of MAPK- and Calcium-signaling pathways, suggesting a relevant contribution of this GEF to modulation of cellular signaling in the cell lineages integrating the pancreatic islets. Whereas the overall transcriptional profile of pancreatic islets was highly specific in comparison to other organs of the same KO mice, a significant specific repression of Pttg1 was a common transcriptional alteration shared with other tissues of neuroectodermal origin. This observation, together with the remarkable pancreatic phenotypic similarities between RasGrf1 KO and Pttg1 KO mice suggested the possibility of proximal functional regulatory links between RasGrf1 and Pttg1 in pancreatic cell lineages expressing these proteins.Analysis of the mPttg1 promoter region identified specific recognition sites for numerous transcription factors which were also found to be differentially expressed in RasGrf1 KO pancreatic islets and are known to be relevant for Ras-ERK signaling as well as beta cell function. Reporter luciferase assays in BT3 insulinoma cells demonstrated the ability of RasGrf1 to modulate mPttg1 promoter activity through ERK-mediated signals. Analysis of the phenotypic interplay between RasGrf1 and Pttg1 in double knockout RasGrf1/Pttg1 mice showed that combined elimination of the two loci resulted in dramatically reduced values of islet and beta cell count and glucose homeostasis function which neared those measured in single Pttg1 KO mice and were significantly lower than those observed in individual RasGrf1 KO mice. CONCLUSIONS The specific transcriptional profile and signaling behavior of RasgGrf1 KO pancreatic islets, together with the dominance of Pttg1 over RasGrf1 with regards to the generation of these phenotypes in mouse pancreas, suggest that RasGrf1 is an important upstream component of signal transduction pathways regulating Pttg1 expression and controlling beta cell development and physiological responses.
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Affiliation(s)
| | | | | | | | - Alberto Fernandez-Medarde
- Centro de Investigación del Cáncer, IBMCC (CSIC-USAL), University of Salamanca, Campus Unamuno, 37007 Salamanca, Spain.
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50
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Grabliauskaite K, Hehl AB, Seleznik GM, Saponara E, Schlesinger K, Zuellig RA, Dittmann A, Bain M, Reding T, Sonda S, Graf R. p21WAF1/Cip1limits senescence and acinar-to-ductal metaplasia formation during pancreatitis. J Pathol 2014; 235:502-14. [DOI: 10.1002/path.4440] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 08/15/2014] [Accepted: 09/09/2014] [Indexed: 01/08/2023]
Affiliation(s)
- Kamile Grabliauskaite
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Adrian B Hehl
- Institute of Parasitology; University of Zurich; Switzerland
| | - Gitta M Seleznik
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Enrica Saponara
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Kathryn Schlesinger
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Richard A Zuellig
- Division of Endocrinology, Diabetes and Clinical Nutrition; University Hospital Zurich; Switzerland
| | - Anja Dittmann
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Martha Bain
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Theresia Reding
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Sabrina Sonda
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
| | - Rolf Graf
- Swiss Hepato-Pancreato-Biliary Centre, Department of Visceral and Transplantation Surgery; University Hospital; Zurich Switzerland
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