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Hu Q, Mu J, Liu Y, Yang Y, Liu Y, Pan Y, Zhang Y, Li L, Liu D, Chen J, Zhang F, Jin L. Obesity-Induced miR-455 Upregulation Promotes Adaptive Pancreatic β-Cell Proliferation Through the CPEB1/CDKN1B Pathway. Diabetes 2022; 71:394-411. [PMID: 35029277 DOI: 10.2337/db21-0134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022]
Abstract
Pancreatic β-cells adapt to compensate for increased metabolic demand during obesity. Although the miRNA pathway has an essential role in β-cell expansion, whether it is involved in adaptive proliferation is largely unknown. First, we report that EGR2 binding to the miR-455 promoter induced miR-455 upregulation in the pancreatic islets of obesity mouse models. Then, in vitro gain- or loss-of-function studies showed that miR-455 overexpression facilitated β-cell proliferation. Knockdown of miR-455 in ob/ob mice via pancreatic intraductal infusion prevented compensatory β-cell expansion. Mechanistically, our results revealed that increased miR-455 expression inhibits the expression of its target cytoplasmic polyadenylation element binding protein 1 (CPEB1), an mRNA binding protein that plays an important role in regulating insulin resistance and cell proliferation. Decreased CPEB1 expression inhibits elongation of the poly(A) tail and the subsequent translation of Cdkn1b mRNA, reducing the CDKN1B expression level and finally promoting β-cell proliferation. Taken together, our results show that the miR-455/CPEB1/CDKN1B pathway contributes to adaptive proliferation of β-cells to meet metabolic demand during obesity.
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Affiliation(s)
- Qianxing Hu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Jinming Mu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Yuhong Liu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Yue Yang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Yue Liu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Yi Pan
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Yanfeng Zhang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Ling Li
- Department of Endocrinology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
- Pancreatic Research Institute, Southeast University, Nanjing, Jiangsu Province, China
| | - Dechen Liu
- Department of Endocrinology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Jianqiu Chen
- College of Engineering, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Fangfang Zhang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
| | - Liang Jin
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu Province, China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, Jiangsu Province, China
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2
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Iorio C, Rourke JL, Wells L, Sakamaki JI, Moon E, Hu Q, Kin T, Screaton RA. Silencing the G-protein coupled receptor 3-salt inducible kinase 2 pathway promotes human β cell proliferation. Commun Biol 2021; 4:907. [PMID: 34302056 PMCID: PMC8302759 DOI: 10.1038/s42003-021-02433-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 07/08/2021] [Indexed: 02/07/2023] Open
Abstract
Loss of pancreatic β cells is the hallmark of type 1 diabetes, for which provision of insulin is the standard of care. While regenerative and stem cell therapies hold the promise of generating single-source or host-matched tissue to obviate immune-mediated complications, these will still require surgical intervention and immunosuppression. Here we report the development of a high-throughput RNAi screening approach to identify upstream pathways that regulate adult human β cell quiescence and demonstrate in a screen of the GPCRome that silencing G-protein coupled receptor 3 (GPR3) leads to human pancreatic β cell proliferation. Loss of GPR3 leads to activation of Salt Inducible Kinase 2 (SIK2), which is necessary and sufficient to drive cell cycle entry, increase β cell mass, and enhance insulin secretion in mice. Taken together, our data show that targeting the GPR3-SIK2 pathway is a potential strategy to stimulate the regeneration of β cells.
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Affiliation(s)
| | - Jillian L Rourke
- Sunnybrook Research Institute, Toronto, Canada
- Mount Allison University, Sackville, NB, Canada
| | - Lisa Wells
- Sunnybrook Research Institute, Toronto, Canada
| | - Jun-Ichi Sakamaki
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Japan
| | - Emily Moon
- Sunnybrook Research Institute, Toronto, Canada
- Department of Biochemistry, University of Toronto, Toronto, Canada
| | - Queenie Hu
- Sunnybrook Research Institute, Toronto, Canada
| | - Tatsuya Kin
- Clinical Islet Laboratory, University of Alberta Hospital, Edmonton, Canada
| | - Robert A Screaton
- Sunnybrook Research Institute, Toronto, Canada.
- Department of Biochemistry, University of Toronto, Toronto, Canada.
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3
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Spears E, Serafimidis I, Powers AC, Gavalas A. Debates in Pancreatic Beta Cell Biology: Proliferation Versus Progenitor Differentiation and Transdifferentiation in Restoring β Cell Mass. Front Endocrinol (Lausanne) 2021; 12:722250. [PMID: 34421829 PMCID: PMC8378310 DOI: 10.3389/fendo.2021.722250] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 07/14/2021] [Indexed: 12/12/2022] Open
Abstract
In all forms of diabetes, β cell mass or function is reduced and therefore the capacity of the pancreatic cells for regeneration or replenishment is a critical need. Diverse lines of research have shown the capacity of endocrine as well as acinar, ductal and centroacinar cells to generate new β cells. Several experimental approaches using injury models, pharmacological or genetic interventions, isolation and in vitro expansion of putative progenitors followed by transplantations or a combination thereof have suggested several pathways for β cell neogenesis or regeneration. The experimental results have also generated controversy related to the limitations and interpretation of the experimental approaches and ultimately their physiological relevance, particularly when considering differences between mouse, the primary animal model, and human. As a result, consensus is lacking regarding the relative importance of islet cell proliferation or progenitor differentiation and transdifferentiation of other pancreatic cell types in generating new β cells. In this review we summarize and evaluate recent experimental approaches and findings related to islet regeneration and address their relevance and potential clinical application in the fight against diabetes.
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Affiliation(s)
- Erick Spears
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Ioannis Serafimidis
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Alvin C. Powers
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States
- VA Tennessee Valley Healthcare System, Nashville, TN, United States
- *Correspondence: Anthony Gavalas, ; Alvin C. Powers,
| | - Anthony Gavalas
- Paul Langerhans Institute Dresden (PLID) of Helmholtz Center Munich at the University Clinic Carl Gustav Carus of TU Dresden, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Centre for Diabetes Research (DZD), Neuherberg, Germany
- *Correspondence: Anthony Gavalas, ; Alvin C. Powers,
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4
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Daurio NA, Zhou H, Chen Y, Sheth PR, Imbriglio JE, McLaren DG, Tawa P, Rachdaoui N, Previs MJ, Kasumov T, O’Neil J, Previs SF. Examining Targeted Protein Degradation from Physiological and Analytical Perspectives: Enabling Translation between Cells and Subjects. ACS Chem Biol 2020; 15:2623-2635. [PMID: 32930572 DOI: 10.1021/acschembio.0c00380] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The ability to target specific proteins for degradation may open a new door toward developing therapeutics. Although effort in chemistry is essential for advancing this modality, i.e., one needs to generate proteolysis targeting chimeras (bifunctional molecules, also referred to as PROTACS) or "molecular glues" to accelerate protein degradation, we suspect that investigations could also benefit by directing attention toward physiological regulation surrounding protein homeostasis, including the methods that can be used to examine changes in protein kinetics. This perspective will first consider some metabolic scenarios that might be of importance when one aims to change protein abundance by increasing protein degradation. Specifically, could protein turnover impact the apparent outcome? We will then outline how to study protein dynamics by coupling stable isotope tracer methods with mass spectrometry-based detection; since the experimental conditions could have a dramatic effect on protein turnover, special attention is directed toward the application of methods for quantifying protein kinetics using in vitro and in vivo models. Our goal is to present key concepts that should enable mechanistically informed studies which test targeted protein degradation strategies.
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Affiliation(s)
- Natalie A. Daurio
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Haihong Zhou
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Ying Chen
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Payal R. Sheth
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Jason E. Imbriglio
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - David G. McLaren
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Paul Tawa
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Nadia Rachdaoui
- Department of Animal Sciences, Rutgers, the State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Michael J. Previs
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont 05454, United States
| | - Takhar Kasumov
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, Ohio 44272, United States
| | - Jennifer O’Neil
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Stephen F. Previs
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
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5
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Niu M, Liu Y, Xiang L, Zhao Y, Yuan J, Jia Y, Dai X, Chen H. Long-term case study of a Wuzhishan miniature pig with diabetes. Animal Model Exp Med 2020; 3:22-31. [PMID: 32318656 PMCID: PMC7167240 DOI: 10.1002/ame2.12098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/28/2019] [Accepted: 12/11/2019] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Miniature pigs are attractive animal models for exploring diabetes because they are similar to humans in terms of physiological structure and metabolism. However, little is known about the complications of diabetes in pigs. METHODS In this study, a 28-month observation of a Wuzhishan miniature pig with streptozotocin (STZ)-induced (120 mg/kg) diabetes was conducted, to investigate diabetes-related complications and the possibility of self-recovery in miniature pigs. Blood glucose, serum and urinary biochemistry was measured, and histopathologic examinations of eyes, kidney and pancreas were made. RESULTS During the observation, diabetic complications of eyes and kidney were observed. The eye complications included bilateral cataracts in the 15th month and degeneration of inner retina and microaneurysm in the 28th month. Kidney complications included glomerular mesangial expansion, focal segmental glomerular sclerosis, and renal tubular epithelial degeneration, but no proteinuria was observed. By 28 months after the application of STZ, with no treatment given, blood glucose had recovered and the number of pancreatic islet beta-cells had increased significantly. CONCLUSIONS We showed that the STZ-induced diabetes model in miniature pigs could accurately mimic the pathological changes of human diabetes, and that pancreatic islet beta-cell regeneration did occur in an adult miniature pig, providing a new means for exploring diabetic complications and pancreatic islet beta-cell regeneration.
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Affiliation(s)
- Miaomiao Niu
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Yaqian Liu
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Lei Xiang
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Yuqiong Zhao
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Jifang Yuan
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Yunxiao Jia
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Xin Dai
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Hua Chen
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
- State Key Laboratory of Kidney DiseasesChinese PLA General HospitalBeijingPR China
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Baeyens L, Lemper M, Staels W, De Groef S, De Leu N, Heremans Y, German MS, Heimberg H. (Re)generating Human Beta Cells: Status, Pitfalls, and Perspectives. Physiol Rev 2018; 98:1143-1167. [PMID: 29717931 DOI: 10.1152/physrev.00034.2016] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Diabetes mellitus results from disturbed glucose homeostasis due to an absolute (type 1) or relative (type 2) deficiency of insulin, a peptide hormone almost exclusively produced by the beta cells of the endocrine pancreas in a tightly regulated manner. Current therapy only delays disease progression through insulin injection and/or oral medications that increase insulin secretion or sensitivity, decrease hepatic glucose production, or promote glucosuria. These drugs have turned diabetes into a chronic disease as they do not solve the underlying beta cell defects or entirely prevent the long-term complications of hyperglycemia. Beta cell replacement through islet transplantation is a more physiological therapeutic alternative but is severely hampered by donor shortage and immune rejection. A curative strategy should combine newer approaches to immunomodulation with beta cell replacement. Success of this approach depends on the development of practical methods for generating beta cells, either in vitro or in situ through beta cell replication or beta cell differentiation. This review provides an overview of human beta cell generation.
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Affiliation(s)
- Luc Baeyens
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
| | - Marie Lemper
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
| | - Willem Staels
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
| | - Sofie De Groef
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
| | - Nico De Leu
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
| | - Yves Heremans
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
| | - Michael S German
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
| | - Harry Heimberg
- Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Brussels , Belgium ; Diabetes Center, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Medicine, University of California San Francisco , San Francisco, California ; Genentech Safety Assessment, South San Francisco, California ; Investigative Toxicology, UCB BioPharma, Braine-l'Alleud, Belgium ; Department of Pediatrics, Division of Pediatric Endocrinology, Ghent University, Hospital and Department of Pediatrics and Genetics , Ghent , Belgium ; Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels , Belgium ; and Department of Endocrinology, Algemeen Stedelijk Ziekenhuis Aalst, Aalst, Belgium
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7
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Zhao Y, Liu Y, Yuan J, Dai X, Niu M, Sun X, Kuang D, Wang W, Tong P, Li N, Xiang L, Jia Y, Dai J, Chen H. Regeneration of islet β-cells in tree shrews and rats. Animal Model Exp Med 2018; 1:152-161. [PMID: 30891560 PMCID: PMC6388076 DOI: 10.1002/ame2.12023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 06/11/2018] [Indexed: 01/08/2023] Open
Abstract
BACKGROUD Current understanding of injury and regeneration of islet β-cells in diabetes is mainly based on rodent studies. The tree shrew is now generally accepted as being among the closest living relatives of primates, and has been widely used in animal experimentation. However, there are few reports on islet cell composition and regeneration of β-cells in tree shrews. METHODS In this study, we examined the changes in islet cell composition and regeneration of β-cells after streptozotocin (STZ) treatment in tree shrews compared with Sprague-Dawley rats. Injury and regeneration of islet β-cells were observed using hematoxylin and eosin (HE) staining and immunohistochemical staining for insulin, glucagon, somatostatin and PDX-1. RESULTS Our data showed that in rats islet injury was most obvious on day 3 after injection, and islet morphologies were significantly restored by day 21. Regeneration of islet β-cells was very pronounced in rats, and mainly involved regeneration of centro-acinar cells and transformation of extra-islet ductal cells. In tree shrews, the regeneration of islet β-cells was not as significant. On days 3 and 7, only scattered regenerated cells were observed in the remaining islets. Further, no regeneration of centro-acinar cells was observed. CONCLUSION The results suggest that the repair mechanism of islet β-cells in tree shrews is similar to that of humans.
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Affiliation(s)
- Yu‐Qiong Zhao
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
| | - Ya‐Qian Liu
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
| | - Ji‐Fang Yuan
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
| | - Xin Dai
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
| | - Miao‐Miao Niu
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
| | - Xiao‐Mei Sun
- The Institute of Medical BiologyThe Chinese Academy of Medical Science and Peking Union Medical CollegeKunmingChina
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious DiseasesCenter of Tree Shrew Germplasm ResourcesKunmingChina
| | - De‐Xuan Kuang
- The Institute of Medical BiologyThe Chinese Academy of Medical Science and Peking Union Medical CollegeKunmingChina
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious DiseasesCenter of Tree Shrew Germplasm ResourcesKunmingChina
| | - Wen‐Guang Wang
- The Institute of Medical BiologyThe Chinese Academy of Medical Science and Peking Union Medical CollegeKunmingChina
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious DiseasesCenter of Tree Shrew Germplasm ResourcesKunmingChina
| | - Pin‐Fen Tong
- The Institute of Medical BiologyThe Chinese Academy of Medical Science and Peking Union Medical CollegeKunmingChina
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious DiseasesCenter of Tree Shrew Germplasm ResourcesKunmingChina
| | - Na Li
- The Institute of Medical BiologyThe Chinese Academy of Medical Science and Peking Union Medical CollegeKunmingChina
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious DiseasesCenter of Tree Shrew Germplasm ResourcesKunmingChina
| | - Lei Xiang
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
| | - Yun‐Xiao Jia
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
| | - Jie‐Jie Dai
- The Institute of Medical BiologyThe Chinese Academy of Medical Science and Peking Union Medical CollegeKunmingChina
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious DiseasesCenter of Tree Shrew Germplasm ResourcesKunmingChina
| | - Hua Chen
- Chinese PLA General HospitalLaboratory Animal CenterBeijingChina
- State Key Laboratory of Kidney DiseasesChinese PLA General HospitalBeijingChina
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8
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Aguayo-Mazzucato C, Bonner-Weir S. Pancreatic β Cell Regeneration as a Possible Therapy for Diabetes. Cell Metab 2018; 27:57-67. [PMID: 28889951 PMCID: PMC5762410 DOI: 10.1016/j.cmet.2017.08.007] [Citation(s) in RCA: 149] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 07/05/2017] [Accepted: 08/08/2017] [Indexed: 02/08/2023]
Abstract
Diabetes is the result of having inadequate supply of functional insulin-producing β cells. Two possible approaches for replenishing the β cells are: (1) replacement by transplanting cadaveric islets or β cells derived from human embryonic stem cells/induced pluripotent stem cells and (2) induction of endogenous regeneration. This review focuses on endogenous regeneration, which can follow two pathways: enhanced replication of existing β cells and formation of new β cells from cells not expressing insulin, either by conversion from a differentiated cell type (transdifferentiation) or differentiation from progenitors (neogenesis). Exciting progress on both pathways suggest that regeneration may have therapeutic promise.
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Affiliation(s)
| | - Susan Bonner-Weir
- Joslin Diabetes Center, Harvard Medical School, Harvard Stem Cell Institute, Boston, MA 02215, USA.
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9
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Heart EA, Karandrea S, Liang X, Balke ME, Beringer PA, Bobczynski EM, Zayas-Bazán Burgos D, Richardson T, Gray JP. Mechanisms of Doxorubicin Toxicity in Pancreatic β-Cells. Toxicol Sci 2016; 152:395-405. [PMID: 27255381 DOI: 10.1093/toxsci/kfw096] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Exposure to chemotherapeutic agents has been linked to an increased risk of type 2 diabetes (T2D), a disease characterized by both the peripheral insulin resistance and impaired glucose-stimulated insulin secretion (GSIS) from pancreatic β-cells. Using the rat β-cell line INS-1 832/13 and isolated mouse pancreatic islets, we investigated the effect of the chemotherapeutic drug doxorubicin (Adriamycin) on pancreatic β-cell survival and function. Exposure of INS-1 832/13 cells to doxorubicin caused impairment of GSIS, cellular viability, an increase in cellular toxicity, as soon as 6 h post-exposure. Doxorubicin impaired plasma membrane electron transport (PMET), a pathway dependent on reduced equivalents NADH and NADPH, but failed to redox cycle in INS-1 832/13 cells and with their lysates. Although NADPH/NADP(+ )content was unaffected, NADH/NAD(+ )content decreased at 4 h post-exposure to doxorubicin, and was followed by a reduction in ATP content. Previous studies have demonstrated that doxorubicin functions as a topoisomerase II inhibitor via induction of DNA cross-linking, resulting in apoptosis. Doxorubicin induced the expression of mRNA for mdm2, cyclin G1, and fas whereas downregulating p53, and increased the melting temperature of genomic DNA, consistent with DNA damage and induction of apoptosis. Doxorubicin also induced caspase-3 and -7 activity in INS-1 832/13 cells and mouse islets; co-treatment with the pan-caspase inhibitor Z-VAD-FMK temporarily attenuated the doxorubicin-mediated loss of viability in INS-1 832/13 cells. Together, these data suggest that DNA damage, not H2O2 produced via redox cycling, is a major mechanism of doxorubicin toxicity in pancreatic β-cells.
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Affiliation(s)
- Emma A Heart
- *Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612
| | - Shpetim Karandrea
- *Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612
| | - Xiaomei Liang
- *Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612
| | - Maren E Balke
- Department of Science, United States Coast Guard Academy, New London, Connecticut 06320
| | - Patrick A Beringer
- Department of Science, United States Coast Guard Academy, New London, Connecticut 06320
| | - Elyse M Bobczynski
- Department of Science, United States Coast Guard Academy, New London, Connecticut 06320
| | | | | | - Joshua P Gray
- *Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612 Department of Science, United States Coast Guard Academy, New London, Connecticut 06320
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10
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Dai C, Kayton NS, Shostak A, Poffenberger G, Cyphert HA, Aramandla R, Thompson C, Papagiannis IG, Emfinger C, Shiota M, Stafford JM, Greiner DL, Herrera PL, Shultz LD, Stein R, Powers AC. Stress-impaired transcription factor expression and insulin secretion in transplanted human islets. J Clin Invest 2016; 126:1857-70. [PMID: 27064285 DOI: 10.1172/jci83657] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 02/24/2016] [Indexed: 12/11/2022] Open
Abstract
Type 2 diabetes is characterized by insulin resistance, hyperglycemia, and progressive β cell dysfunction. Excess glucose and lipid impair β cell function in islet cell lines, cultured rodent and human islets, and in vivo rodent models. Here, we examined the mechanistic consequences of glucotoxic and lipotoxic conditions on human islets in vivo and developed and/or used 3 complementary models that allowed comparison of the effects of hyperglycemic and/or insulin-resistant metabolic stress conditions on human and mouse islets, which responded quite differently to these challenges. Hyperglycemia and/or insulin resistance impaired insulin secretion only from human islets in vivo. In human grafts, chronic insulin resistance decreased antioxidant enzyme expression and increased superoxide and amyloid formation. In human islet grafts, expression of transcription factors NKX6.1 and MAFB was decreased by chronic insulin resistance, but only MAFB decreased under chronic hyperglycemia. Knockdown of NKX6.1 or MAFB expression in a human β cell line recapitulated the insulin secretion defect seen in vivo. Contrary to rodent islet studies, neither insulin resistance nor hyperglycemia led to human β cell proliferation or apoptosis. These results demonstrate profound differences in how excess glucose or lipid influence mouse and human insulin secretion and β cell activity and show that reduced expression of key islet-enriched transcription factors is an important mediator of glucotoxicity and lipotoxicity.
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11
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Robitaille K, Rourke JL, McBane JE, Fu A, Baird S, Du Q, Kin T, Shapiro AMJ, Screaton RA. High-throughput Functional Genomics Identifies Regulators of Primary Human Beta Cell Proliferation. J Biol Chem 2016; 291:4614-25. [PMID: 26740620 PMCID: PMC4813485 DOI: 10.1074/jbc.m115.683912] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Indexed: 02/05/2023] Open
Abstract
The expansion of cells for regenerative therapy will require the genetic dissection of complex regulatory mechanisms governing the proliferation of non-transformed human cells. Here, we report the development of a high-throughput RNAi screening strategy specifically for use in primary cells and demonstrate that silencing the cell cycle-dependent kinase inhibitors CDKN2C/p18 or CDKN1A/p21 facilitates cell cycle entry of quiescent adult human pancreatic beta cells. This work identifies p18 and p21 as novel targets for promoting proliferation of human beta cells and demonstrates the promise of functional genetic screens for dissecting therapeutically relevant state changes in primary human cells.
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Affiliation(s)
- Karine Robitaille
- From the Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1
| | | | - Joanne E McBane
- From the Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1
| | - Accalia Fu
- From the Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1, the Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5
| | - Stephen Baird
- From the Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1
| | - Qiujiang Du
- the Sunnybrook Research Institute, Toronto, Ontario M4N 3M5
| | - Tatsuya Kin
- the Clinical Islet Transplant Program, University of Alberta, 8215-112 Street, Edmonton, Alberta T6G 2C8, and
| | - A M James Shapiro
- the Clinical Islet Transplant Program, University of Alberta, 8215-112 Street, Edmonton, Alberta T6G 2C8, and
| | - Robert A Screaton
- the Sunnybrook Research Institute, Toronto, Ontario M4N 3M5, the Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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12
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Abstract
The prevalence of type 2 diabetes is increasing worldwide, and while numerous treatments exist, none of the current pharmacologic therapies is curative. Pharmacologic approaches that increase beta cell mass may present an avenue for actual cure. There have been numerous reports on factors that can induce beta cell proliferation in rodents, whereas there are still very limited data on the occurrence of beta cell proliferation in humans. The recent discovery of the hormone betatrophin, which in mice counteracted glucose intolerance induced by insulin resistance by potently stimulating beta cell proliferation, has boosted the hope for a new target for drug development for the treatment of diabetes mellitus in humans. With the encouraging preclinical findings as a background, this review presents the available clinical data on betatrophin and discusses its possible role in humans.
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Affiliation(s)
- Daniel Espes
- Department of Medical Cell Biology, Uppsala University, BMC, Husargatan 3, Box 571, Uppsala, SE-75123, Sweden.
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
| | - Mats Martinell
- Department of Public Health Care, Uppsala University, BMC, Husargatan 3, Box 564, Uppsala, 75122, Sweden.
| | - Hanna Liljebäck
- Department of Medical Cell Biology, Uppsala University, BMC, Husargatan 3, Box 571, Uppsala, SE-75123, Sweden.
| | - Per-Ola Carlsson
- Department of Medical Cell Biology, Uppsala University, BMC, Husargatan 3, Box 571, Uppsala, SE-75123, Sweden.
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
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13
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Aggarwal S, Shailendra G, Ribnicky DM, Burk D, Karki N, Qingxia Wang MS. An extract of Artemisia dracunculus L. stimulates insulin secretion from β cells, activates AMPK and suppresses inflammation. JOURNAL OF ETHNOPHARMACOLOGY 2015; 170:98-105. [PMID: 25980421 PMCID: PMC4470741 DOI: 10.1016/j.jep.2015.05.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 04/27/2015] [Accepted: 05/02/2015] [Indexed: 05/23/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Artemisia dracunculus L. (Russian tarragon) is a perennial herb belonging to the family Compositae and has a history of medicinal use in humans, particularly for treatment of diabetes. AIM OF THE STUDY In this study a defined plant extract from A. dracunculus L. (termed PMI-5011) is used to improve beta(β) cells function and maintain β cell number in pancreatic islets as an alternative drug approach for successful treatment of diabetes. MATERIALS AND METHODS Mouse and human pancreatic beta cells were treated with defined plant extract of A. dracunculus L. (PMI-5011) to understand the mechanism(s) that influence beta cell function and β cell number. RESULTS We found that the PMI-5011 enhances insulin release from primary β cells, isolated mouse and human islets and it maintains β cell number. Insulin released by PMI-5011 is associated with the activation of AMP-activated protein kinase (AMPK), and protein kinase B (PKB). Furthermore, PMI-5011 suppresses LPS/INFγ-induced inflammation and inflammatory mediator(s) in macrophages. PMI-5011 inhibited Nitric oxide (NO) production and expression of inducible nitric oxide synthase (iNOS) at the protein level and also attenuated pro-inflammatory cytokine (IL-6) production in macrophages. CONCLUSION PMI-5011 has potential therapeutic value for diabetes treatment via increasing insulin release from β cells and decreases capacity of macrophages to combat inflammation.
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Affiliation(s)
- Sita Aggarwal
- William Hansel Cancer Prevention Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA.
| | - Giri Shailendra
- Department of Experimental Pathology, Mayo Clinic, Rochester, MN 55905, USA
| | - David M Ribnicky
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ 08901-8521, USA
| | - David Burk
- Cell Biology and Bio-imaging, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA
| | - Namrata Karki
- William Hansel Cancer Prevention Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - M S Qingxia Wang
- William Hansel Cancer Prevention Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
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14
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Zhou H, Wang SP, Herath K, Kasumov T, Sadygov RG, Previs SF, Kelley DE. Tracer-based estimates of protein flux in cases of incomplete product renewal: evidence and implications of heterogeneity in collagen turnover. Am J Physiol Endocrinol Metab 2015; 309:E115-21. [PMID: 26015435 PMCID: PMC4596733 DOI: 10.1152/ajpendo.00435.2014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 05/04/2015] [Indexed: 11/22/2022]
Abstract
The synthesis of various molecules can be estimated by measuring the incorporation of a labeled precursor into a product of interest. Unfortunately, a central problem in many studies has been an inability to estimate the intracellular dilution of the precursor and therein correctly calculate the synthesis of the product; it is generally assumed that measuring the true product labeling is straightforward. We initiated a study to examine liver collagen synthesis and identified an apparent problem with assumptions regarding measurements of the product labeling. Since it is well known that collagen production is relatively slow, we relied on the use of [(2)H]H2O labeling (analogous to a primed infusion) and sampled animals over the course of 16 days. Although the water labeling (the precursor) remained stable and we observed the incorporation of labeled amino acids into collagen, the asymptotic protein labeling was considerably lower than what would be expected based on the precursor labeling. Although this observation is not necessarily surprising (i.e., one might expect that a substantial fraction of the collagen pool would appear "inert" or turn over at a very slow rate), its implications are of interest in certain areas. Herein, we discuss a novel situation in which tracers are used to quantify rates of flux under conditions where a product may not undergo complete replacement. We demonstrate how heterogeneity in the product pool can lead one to the wrong conclusions regarding estimates of flux, and we outline an approach that may help to minimize errors surrounding data interpretation.
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Affiliation(s)
- Haihong Zhou
- Cardiometabolic Disease, Merck Research Laboratories, Kenilworth, New Jersey
| | - Sheng-Ping Wang
- Cardiometabolic Disease, Merck Research Laboratories, Kenilworth, New Jersey
| | - Kithsiri Herath
- Cardiometabolic Disease, Merck Research Laboratories, Kenilworth, New Jersey
| | - Takhar Kasumov
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, Ohio; and
| | - Rovshan G Sadygov
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Stephen F Previs
- Cardiometabolic Disease, Merck Research Laboratories, Kenilworth, New Jersey;
| | - David E Kelley
- Cardiometabolic Disease, Merck Research Laboratories, Kenilworth, New Jersey
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15
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Tomasetti C, Vogelstein B. Cancer etiology. Variation in cancer risk among tissues can be explained by the number of stem cell divisions. Science 2015; 347:78-81. [PMID: 25554788 PMCID: PMC4446723 DOI: 10.1126/science.1260825] [Citation(s) in RCA: 1194] [Impact Index Per Article: 132.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Some tissue types give rise to human cancers millions of times more often than other tissue types. Although this has been recognized for more than a century, it has never been explained. Here, we show that the lifetime risk of cancers of many different types is strongly correlated (0.81) with the total number of divisions of the normal self-renewing cells maintaining that tissue's homeostasis. These results suggest that only a third of the variation in cancer risk among tissues is attributable to environmental factors or inherited predispositions. The majority is due to "bad luck," that is, random mutations arising during DNA replication in normal, noncancerous stem cells. This is important not only for understanding the disease but also for designing strategies to limit the mortality it causes.
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Affiliation(s)
- Cristian Tomasetti
- Division of Biostatistics and Bioinformatics, Department of Oncology, Sidney Kimmel Cancer Center, Johns Hopkins University School of Medicine and Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, 550 North Broadway, Baltimore, MD 21205, USA.
| | - Bert Vogelstein
- Ludwig Center for Cancer Genetics and Therapeutics and Howard Hughes Medical Institute, Johns Hopkins Kimmel Cancer Center, 1650 Orleans Street, Baltimore, MD 21205, USA.
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16
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Abstract
Because obesity rates have increased dramatically over the past 3 decades, type 2 diabetes has become increasingly prevalent as well. Type 2 diabetes is associated with decreased pancreatic β-cell mass and function, resulting in inadequate insulin production. Conversely, in nondiabetic obesity, an expansion in β-cell mass occurs to provide sufficient insulin and to prevent hyperglycemia. This expansion is at least in part due to β-cell proliferation. This review focuses on the mechanisms regulating obesity-induced β-cell proliferation in humans and mice. Many factors have potential roles in the regulation of obesity-driven β-cell proliferation, including nutrients, insulin, incretins, hepatocyte growth factor, and recently identified liver-derived secreted factors. Much is still unknown about the regulation of β-cell replication, especially in humans. The extracellular signals that activate proliferative pathways in obesity, the relative importance of each of these pathways, and the extent of cross-talk between these pathways are important areas of future study.
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Affiliation(s)
| | - Mieke Baan
- Division of Endocrinology, Department of Medicine, and,School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI; and
| | - Dawn Belt Davis
- Division of Endocrinology, Department of Medicine, and William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin
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17
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Nichols RJ, New C, Annes JP. Adult tissue sources for new β cells. Transl Res 2014; 163:418-31. [PMID: 24345765 PMCID: PMC3976738 DOI: 10.1016/j.trsl.2013.11.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Revised: 11/04/2013] [Accepted: 11/20/2013] [Indexed: 12/25/2022]
Abstract
The diabetes pandemic incurs extraordinary public health and financial costs that are projected to expand for the foreseeable future. Consequently, the development of definitive therapies for diabetes is a priority. Currently, a wide spectrum of therapeutic strategies-from implantable insulin delivery devices to transplantation-based cell replacement therapy, to β-cell regeneration-focus on replacing the lost insulin-producing capacity of individuals with diabetes. Among these, β-cell regeneration remains promising but heretofore unproved. Indeed, recent experimental work has uncovered surprising biology that underscores the potential therapeutic benefit of β-cell regeneration. These studies have elucidated a variety of sources for the endogenous production of new β cells from existing cells. First, β cells, long thought to be postmitotic, have demonstrated the potential for regenerative capacity. Second, the presence of pancreatic facultative endocrine progenitor cells has been established. Third, the malleability of cellular identity has availed the possibility of generating β cells from other differentiated cell types. Here, we review the exciting developments surrounding endogenous sources of β-cell production and consider the potential of realizing a regenerative therapy for diabetes from adult tissues.
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Affiliation(s)
| | - Connie New
- Department of Medicine, Stanford University Medical School, Stanford, Calif
| | - Justin P Annes
- Department of Medicine, Stanford University Medical School, Stanford, Calif.
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18
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Espes D, Martinell M, Carlsson PO. Increased circulating betatrophin concentrations in patients with type 2 diabetes. Int J Endocrinol 2014; 2014:323407. [PMID: 24963292 PMCID: PMC4055101 DOI: 10.1155/2014/323407] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 05/07/2014] [Indexed: 12/31/2022] Open
Abstract
Betatrophin has recently been described as a key hormone to stimulate beta-cell mass expansion in response to insulin resistance and obesity in mice. The finding has generated an interest in the development of antidiabetic drugs with betatrophin as the active component. However, the circulating levels of betatrophin in patients with type 2 diabetes are not well known. Betatrophin concentrations in plasma of 27 type 2 diabetes patients and 18 gender-, age-, and BMI-matched controls were measured. Study participants were characterized with regard to BMI, waist and hip circumference, blood pressure, and fasting plasma blood lipids, creatinine, glucose, HbA1c, and C-peptide. HOMA2 indices were calculated. Betatrophin was 40% higher in patients with type 2 diabetes (893 ± 80 versus 639 ± 66 pg/mL). Betatrophin positively correlated with age in the controls and with HbA1c in the type 2 diabetes patients. All study participants were insulin resistant with mean HOMA2B IR in both groups exceeding 2 and HOMA2%S < 50%. Control individuals had impaired fasting glucose concentrations. In this report on betatrophin concentrations in type 2 diabetes and insulin resistance, elevated betatrophin levels were measured in the patients with type 2 diabetes. Future studies are clearly needed to delineate the exact role, if any, of betatrophin in regulating human beta-cell mass.
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Affiliation(s)
- Daniel Espes
- Department of Medical Cell Biology, Uppsala University, Husargatan 3, P.O. Box 571, 75123 Uppsala, Sweden
- Department of Medical Sciences, Uppsala University Hospital, Uppsala University, 75185 Uppsala, Sweden
| | - Mats Martinell
- Department of Public Health Care, Uppsala University, Husargatan 3, P.O. Box 564, 75122 Uppsala, Sweden
| | - Per-Ola Carlsson
- Department of Medical Cell Biology, Uppsala University, Husargatan 3, P.O. Box 571, 75123 Uppsala, Sweden
- Department of Medical Sciences, Uppsala University Hospital, Uppsala University, 75185 Uppsala, Sweden
- *Per-Ola Carlsson:
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19
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Plaisance V, Waeber G, Regazzi R, Abderrahmani A. Role of microRNAs in islet beta-cell compensation and failure during diabetes. J Diabetes Res 2014; 2014:618652. [PMID: 24734255 PMCID: PMC3964735 DOI: 10.1155/2014/618652] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 01/24/2014] [Indexed: 12/12/2022] Open
Abstract
Pancreatic beta-cell function and mass are markedly adaptive to compensate for the changes in insulin requirement observed during several situations such as pregnancy, obesity, glucocorticoids excess, or administration. This requires a beta-cell compensation which is achieved through a gain of beta-cell mass and function. Elucidating the physiological mechanisms that promote functional beta-cell mass expansion and that protect cells against death, is a key therapeutic target for diabetes. In this respect, several recent studies have emphasized the instrumental role of microRNAs in the control of beta-cell function. MicroRNAs are negative regulators of gene expression, and are pivotal for the control of beta-cell proliferation, function, and survival. On the one hand, changes in specific microRNA levels have been associated with beta-cell compensation and are triggered by hormones or bioactive peptides that promote beta-cell survival and function. Conversely, modifications in the expression of other specific microRNAs contribute to beta-cell dysfunction and death elicited by diabetogenic factors including, cytokines, chronic hyperlipidemia, hyperglycemia, and oxidized LDL. This review underlines the importance of targeting the microRNA network for future innovative therapies aiming at preventing the beta-cell decline in diabetes.
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Affiliation(s)
- Valérie Plaisance
- Lille 2 University, European Genomic Institute for Diabetes (EGID), FR 3508, UMR-8199 Lille, France
| | - Gérard Waeber
- Service of Internal Medicine, Hospital-University of Lausanne (CHUV), 1011 Lausanne, Switzerland
| | - Romano Regazzi
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Amar Abderrahmani
- Lille 2 University, European Genomic Institute for Diabetes (EGID), FR 3508, UMR-8199 Lille, France
- *Amar Abderrahmani:
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20
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Diaz-de-Durana Y, Lau J, Knee D, Filippi C, Londei M, McNamara P, Nasoff M, DiDonato M, Glynne R, Herman AE. IL-2 immunotherapy reveals potential for innate beta cell regeneration in the non-obese diabetic mouse model of autoimmune diabetes. PLoS One 2013; 8:e78483. [PMID: 24205242 PMCID: PMC3813455 DOI: 10.1371/journal.pone.0078483] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 09/12/2013] [Indexed: 01/09/2023] Open
Abstract
Type-1 diabetes (T1D) is an autoimmune disease targeting insulin-producing beta cells, resulting in dependence on exogenous insulin. To date, significant efforts have been invested to develop immune-modulatory therapies for T1D treatment. Previously, IL-2 immunotherapy was demonstrated to prevent and reverse T1D at onset in the non-obese diabetic (NOD) mouse model, revealing potential as a therapy in early disease stage in humans. In the NOD model, IL-2 deficiency contributes to a loss of regulatory T cell function. This deficiency can be augmented with IL-2 or antibody bound to IL-2 (Ab/IL-2) therapy, resulting in regulatory T cell expansion and potentiation. However, an understanding of the mechanism by which reconstituted regulatory T cell function allows for reversal of diabetes after onset is not clearly understood. Here, we describe that Ab/IL-2 immunotherapy treatment, given at the time of diabetes onset in NOD mice, not only correlated with reversal of diabetes and expansion of Treg cells, but also demonstrated the ability to significantly increase beta cell proliferation. Proliferation appeared specific to Ab/IL-2 immunotherapy, as anti-CD3 therapy did not have a similar effect. Furthermore, to assess the effect of Ab/IL-2 immunotherapy well after the development of diabetes, we tested the effect of delaying treatment for 4 weeks after diabetes onset, when beta cells were virtually absent. At this late stage after diabetes onset, Ab/IL-2 treatment was not sufficient to reverse hyperglycemia. However, it did promote survival in the absence of exogenous insulin. Proliferation of beta cells could not account for this improvement as few beta cells remained. Rather, abnormal insulin and glucagon dual-expressing cells were the only insulin-expressing cells observed in islets from mice with established disease. Thus, these data suggest that in diabetic NOD mice, beta cells have an innate capacity for regeneration both early and late in disease, which is revealed through IL-2 immunotherapy.
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Affiliation(s)
- Yaiza Diaz-de-Durana
- Genetics Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
| | - Janet Lau
- Genetics Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
| | - Deborah Knee
- Biotherapeutics Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
| | - Christophe Filippi
- Genetics Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
| | - Marco Londei
- Translational Medicine, Novartis Institutes of Biomedical Research, San Diego, California, United States of America
| | - Peter McNamara
- Pharmacology Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
| | - Marc Nasoff
- Biotherapeutics Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
| | - Michael DiDonato
- Structural Biology Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
| | - Richard Glynne
- Genetics Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
- * E-mail:
| | - Ann E. Herman
- Genetics Department, Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America
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21
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Gargani S, Thévenet J, Yuan JE, Lefebvre B, Delalleau N, Gmyr V, Hubert T, Duhamel A, Pattou F, Kerr-Conte J. Adaptive changes of human islets to an obesogenic environment in the mouse. Diabetologia 2013; 56. [PMID: 23192693 PMCID: PMC3536990 DOI: 10.1007/s00125-012-2775-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AIMS/HYPOTHESIS In this study, we used an immunodeficient mouse model to explore, in vivo, the longitudinal adaptation of human islets to an obesogenic environment. METHODS Non-diabetic Rag2 (-/-) mice (n = 61) were transplanted with human islets (400 islet equivalents [IEQ]) from six pancreases: four non-diabetic and two with overt metabolic dysfunction (older, high HbA(lc) or history of diabetes). Animals were fed for 12 weeks with a control or high-fat diet (HFD), and followed for weight, serum triacylglycerol, fasting blood glucose and human C-peptide. After the mice were killed, human grafts and the endogenous pancreas were analysed for endocrine volume, distribution of beta and alpha cells, and proliferation. RESULTS Transplanted mice on an HFD gained significantly more weight (p < 0.001) and had higher fasting glycaemia (2-12 weeks; p = 0.0002) and consistently higher fasting human C-peptide levels (2-12 weeks; p = 0.04) compared with those on the control diet. Histology demonstrated doubling of human islet graft volume at 12 weeks in animals on the HFD and increased beta cell volume (p < 0.001), but no change in alpha cell volume. Human islet function (hyperbolic product HOMA2%BS) at 12 weeks was four times lower in HFD animals (p < 0.001 vs controls) because of insufficient beta cell adaptation to decreased (70%) sensitivity (HOMA%S). Human islets obtained from donors with metabolic dysfunction failed to adapt to the HFD. CONCLUSIONS/INTERPRETATION This longitudinal study provides direct evidence that human islets adapt both endocrine and beta cell mass, function and gene expression to obesity in vivo. The present model will facilitate the identification of mechanisms by which human islets adapt to obesity in vivo and the cell type(s) responsible, and factors predisposing human beta cells to decompensation.
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Affiliation(s)
- S. Gargani
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Inserm U859 Biotherapies of Diabetes, Faculty of Medicine, 1 Place de Verdun, F59045 Lille, France
| | - J. Thévenet
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Inserm U859 Biotherapies of Diabetes, Faculty of Medicine, 1 Place de Verdun, F59045 Lille, France
| | - J. E. Yuan
- Université Lille Nord de France, Lille, France
| | - B. Lefebvre
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Present Address: Inserm U837, Alzheimer and Tauopathies, Lille, France
| | - N. Delalleau
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Inserm U859 Biotherapies of Diabetes, Faculty of Medicine, 1 Place de Verdun, F59045 Lille, France
| | - V. Gmyr
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Inserm U859 Biotherapies of Diabetes, Faculty of Medicine, 1 Place de Verdun, F59045 Lille, France
| | - T. Hubert
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Inserm U859 Biotherapies of Diabetes, Faculty of Medicine, 1 Place de Verdun, F59045 Lille, France
| | - A. Duhamel
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Centre Hospitalier Régional Universitaire de Lille, Lille, France
- CERIM, Faculty of Medicine, Lille, France
| | - F. Pattou
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Inserm U859 Biotherapies of Diabetes, Faculty of Medicine, 1 Place de Verdun, F59045 Lille, France
- Centre Hospitalier Régional Universitaire de Lille, Lille, France
| | - J. Kerr-Conte
- Université Lille Nord de France, Lille, France
- UDSL, IMPRT, Lille, France
- Inserm U859 Biotherapies of Diabetes, Faculty of Medicine, 1 Place de Verdun, F59045 Lille, France
- Centre Hospitalier Régional Universitaire de Lille, Lille, France
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Caballero F, Siniakowicz K, Hollister-Lock J, Duran L, Katsuta H, Yamada T, Lei J, Deng S, Westermark GT, Markmann J, Bonner-Weir S, Weir GC. Birth and death of human β-cells in pancreases from cadaver donors, autopsies, surgical specimens, and islets transplanted into mice. Cell Transplant 2013; 23:139-51. [PMID: 23321263 DOI: 10.3727/096368912x659916] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
There is great interest in the potential of the human endocrine pancreas for regeneration by β-cell replication or neogenesis. Our aim was to explore this potential in adult human pancreases and in both islet and exocrine tissue transplanted into mice. The design was to examine pancreases obtained from cadaver donors, autopsies, and fresh surgical specimens and compare these findings with those obtained from islet and duct tissue grafted into the kidney. Islets and exocrine tissue were transplanted into normoglycemic ICR-SCID mice and studied 4 and 14 weeks later. β-Cell replication, as assessed by double staining for insulin and Ki67, was 0.22 ± 0.03% at 4 weeks and 0.13 ± 0.03% at 14 weeks. In contrast, no evidence of β-cell replication could be found in 11 cadaver donor and 10 autopsy pancreases. However, Ki67 staining of β-cells in frozen sections obtained at surgery was comparable to that found in transplanted islets. Evidence for neogenesis in transplanted pancreatic exocrine tissue was supported by finding β-cells within the duct epithelium and the presence of cells double stained for insulin and cytokeratin 19 (CK19). However, β-cells within the ducts never constituted more than 1% of the CK19-positive cells. With confocal microscopy, 7 of 12 examined cells expressed both markers, consistent with a neogeneic process. Mice with grafts containing islet or exocrine tissue were treated with various combinations of exendin-4, gastrin, and epidermal growth factor; none increased β-cell replication or stimulated neogenesis. In summary, human β-cells replicate at a low level in islets transplanted into mice and in surgical pancreatic frozen sections, but rarely in cadaver donor or autopsy pancreases. The absence of β-cell replication in many adult cadaver or autopsy pancreases could, in part, be an artifact of the postmortem state. Thus, it appears that adult human β-cells maintain a low level of turnover through replication and neogenesis.
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Affiliation(s)
- Francisco Caballero
- Section on Islet Cell and Regenerative Biology, Research Division, Joslin Diabetes Center, Boston, MA, USA
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Bonner-Weir S, Guo L, Li WC, Ouziel-Yahalom L, Lysy PA, Weir GC, Sharma A. Islet neogenesis: a possible pathway for beta-cell replenishment. Rev Diabet Stud 2012; 9:407-16. [PMID: 23804276 DOI: 10.1900/rds.2012.9.407] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Diabetes, particularly type 1 diabetes, results from the lack of pancreatic β-cells. β-cell replenishment can functionally reverse diabetes, but two critical challenges face the field: 1. protection of the new β-cells from autoimmunity and allorejection, and 2. development of β-cells that are readily available and reliably functional. This chapter will examine the potential of endogenous replenishment of pancreatic β-cells as a possible therapeutic tool if autoimmunity could be blunted. Two pathways for endogenous replenishment exist in the pancreas: replication and neogenesis, defined as the formation of new islet cells from pancreatic progenitor/stem cells. These pathways of β-cell expansion are not mutually exclusive and both occur in embryonic development, in postnatal growth, and in response to some injuries. Since the β-cell population is dramatically reduced in the pancreas of type 1 diabetes patients, with only a small fraction of the β-cells surviving years after onset, replication of preexisting β-cells would not be a reasonable start for replenishment. However, induction of neogenesis could provide a starting population that could be further expanded by replication. It is widely accepted that neogenesis occurs in the initial embryonic formation of the endocrine pancreas, but its occurrence anytime after birth has become controversial because of discordant data from lineage tracing experiments. However, the concept was built upon many observations from different models and species over many years. Herein, we discuss the role of neogenesis in normal growth and regeneration, as learned from rodent models, followed by an analysis of what has been found in humans.
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Affiliation(s)
- Susan Bonner-Weir
- Joslin Diabetes Center, Department of Medicine, Harvard Medical School, 1 Joslin Place, Boston, MA 02215, USA.
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Adenosine kinase inhibition selectively promotes rodent and porcine islet β-cell replication. Proc Natl Acad Sci U S A 2012; 109:3915-20. [PMID: 22345561 DOI: 10.1073/pnas.1201149109] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Diabetes is a pathological condition characterized by relative insulin deficiency, persistent hyperglycemia, and, consequently, diffuse micro- and macrovascular disease. One therapeutic strategy is to amplify insulin-secretion capacity by increasing the number of the insulin-producing β cells without triggering a generalized proliferative response. Here, we present the development of a small-molecule screening platform for the identification of molecules that increase β-cell replication. Using this platform, we identify a class of compounds [adenosine kinase inhibitors (ADK-Is)] that promote replication of primary β cells in three species (mouse, rat, and pig). Furthermore, the replication effect of ADK-Is is cell type-selective: treatment of islet cell cultures with ADK-Is increases replication of β cells but not that of α cells, PP cells, or fibroblasts. Short-term in vivo treatment with an ADK-I also increases β-cell replication but not exocrine cell or hepatocyte replication. Therefore, we propose ADK inhibition as a strategy for the treatment of diabetes.
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Levitt HE, Cyphert TJ, Pascoe JL, Hollern DA, Abraham N, Lundell RJ, Rosa T, Romano LC, Zou B, O'Donnell CP, Stewart AF, Garcia-Ocaña A, Alonso LC. Glucose stimulates human beta cell replication in vivo in islets transplanted into NOD-severe combined immunodeficiency (SCID) mice. Diabetologia 2011; 54:572-82. [PMID: 20936253 PMCID: PMC3034833 DOI: 10.1007/s00125-010-1919-1] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 08/31/2010] [Indexed: 12/22/2022]
Abstract
AIMS/HYPOTHESIS We determined whether hyperglycaemia stimulates human beta cell replication in vivo in an islet transplant model METHODS Human islets were transplanted into streptozotocin-induced diabetic NOD-severe combined immunodeficiency mice. Blood glucose was measured serially during a 2 week graft revascularisation period. Engrafted mice were then catheterised in the femoral artery and vein, and infused intravenously with BrdU for 4 days to label replicating beta cells. Mice with restored normoglycaemia were co-infused with either 0.9% (wt/vol.) saline or 50% (wt/vol.) glucose to generate glycaemic differences among grafts from the same donors. During infusions, blood glucose was measured daily. After infusion, human beta cell replication and apoptosis were measured in graft sections using immunofluorescence for insulin, and BrdU or TUNEL. RESULTS Human islet grafts corrected diabetes in the majority of cases. Among grafts from the same donor, human beta cell proliferation doubled in those exposed to higher glucose relative to lower glucose. Across the entire cohort of grafts, higher blood glucose was strongly correlated with increased beta cell replication. Beta cell replication rates were unrelated to circulating human insulin levels or donor age, but tended to correlate with donor BMI. Beta cell TUNEL reactivity was not measurably increased in grafts exposed to elevated blood glucose. CONCLUSIONS/INTERPRETATION Glucose is a mitogenic stimulus for transplanted human beta cells in vivo. Investigating the underlying pathways may point to mechanisms capable of expanding human beta cell mass in vivo.
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Affiliation(s)
- H E Levitt
- Division of Endocrinology and Metabolism, University of Pittsburgh School of Medicine, 200 Lothrop St, BST E1140, Pittsburgh, PA 15261, USA
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26
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Bonner-Weir S, Li WC, Ouziel-Yahalom L, Guo L, Weir GC, Sharma A. Beta-cell growth and regeneration: replication is only part of the story. Diabetes 2010; 59:2340-8. [PMID: 20876724 PMCID: PMC3279552 DOI: 10.2337/db10-0084] [Citation(s) in RCA: 195] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Susan Bonner-Weir
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA.
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Abstract
Gut microbiota is an assortment of microorganisms inhabiting the length and width of the mammalian gastrointestinal tract. The composition of this microbial community is host specific, evolving throughout an individual's lifetime and susceptible to both exogenous and endogenous modifications. Recent renewed interest in the structure and function of this "organ" has illuminated its central position in health and disease. The microbiota is intimately involved in numerous aspects of normal host physiology, from nutritional status to behavior and stress response. Additionally, they can be a central or a contributing cause of many diseases, affecting both near and far organ systems. The overall balance in the composition of the gut microbial community, as well as the presence or absence of key species capable of effecting specific responses, is important in ensuring homeostasis or lack thereof at the intestinal mucosa and beyond. The mechanisms through which microbiota exerts its beneficial or detrimental influences remain largely undefined, but include elaboration of signaling molecules and recognition of bacterial epitopes by both intestinal epithelial and mucosal immune cells. The advances in modeling and analysis of gut microbiota will further our knowledge of their role in health and disease, allowing customization of existing and future therapeutic and prophylactic modalities.
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Affiliation(s)
- Inna Sekirov
- Michael Smith Laboratories, Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
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beta-cell function in obese-hyperglycemic mice [ob/ob Mice]. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 654:463-77. [PMID: 20217510 DOI: 10.1007/978-90-481-3271-3_20] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
This review summarizes key aspects of what has been learned about the physiology of pancreatic islets and leptin deficiency from studies in obese ob/ob mice. ob/ob Mice lack functional leptin. They are grossly overweight and hyperphagic particularly at young ages and develop severe insulin resistance with hyperglycemia and hyperinsulinemia. ob/ob Mice have large pancreatic islets. The beta-cells respond adequately to most stimuli, and ob/ob mice have been used as a rich source of pancreatic islets with high insulin release capacity. ob/ob Mice can perhaps be described as a model for the prediabetic state. The large capacity for islet growth and insulin release makes ob/ob mice a good model for studies on how beta-cells can cope with prolonged functional stress.
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Abstract
Prospects for inducing endogenous beta-cell regeneration in the pancreas, one of the most attractive approaches to reverse type 1 and type 2 diabetes, have gained substantially from recent evidence that cells in the adult pancreas exhibit more plasticity than previously recognized. There are two major pathways to beta-cell regeneration, beta-cell replication and beta-cell neogenesis. Substantial evidence for a role for both processes exists in different models. While beta-cell replication clearly occurs during development and early in life, the potential for replication appears to decline substantially with age. In contrast, we have demonstrated that the exocrine compartment of the adult human pancreas contains a facultative stem cell that can differentiate into beta-cells under specific circumstances. We have favoured the idea that, similar to models described in liver regeneration, beta-cell mass can be increased either by neogenesis or replication, depending on the intensity of different stimuli or stressors. Understanding the nature of endocrine stem/progenitor cells and the mechanism by which external stimuli mobilize them to exhibit endocrine differentiation is central for success in therapeutic approaches to induce meaningful endogenous beta-cell neogenesis.
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Affiliation(s)
- C Demeterco
- Department of Pediatrics, University of California San Diego, Rady Children's Hospital, La Jolla, USA
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30
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Comparative study of regenerative potential of beta cells from young and aged donor mice using a novel islet transplantation model. Transplantation 2009; 88:496-503. [PMID: 19696632 DOI: 10.1097/tp.0b013e3181b0d2ee] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND The effect of ageing on beta-cell regeneration under hyperglycemia has not been defined and may best be addressed using a unique islet-transplantation model. METHODS Streptozotocin-induced diabetic FVB/NJ mice were rendered normoglycemic with a therapeutic mass of syngeneic islets implanted in the epididymal fat pad, followed by a subrenal capsular implantation of a subtherapeutic mass of 25 islets from young (3 months) or old (24 months) mice. Three weeks after the second transplant, the islet containing fat pad was removed to reintroduce hyperglycemia. Bromodeoxyuridine (BrdU) was provided to mice continuously in drinking water. Islet grafts under the kidney capsule were harvested at different time points and examined for markers of beta-cell regeneration by immunohistochemistry. RESULTS After a 7-day labeling, BrdU was detected in 54.2% or 53.0% beta cells of the young or old islet grafts, respectively, under hyperglycemia when compared with 3.3% in grafts under normoglycemia. Ki67-positive beta cells were enhanced from a baseline level of 0.5% to 5.2% (young islets) or 4.0% (old islets) on day 7 of hyperglycemia, then decreased to 2.4% on day 21, at which time point an accumulative 75.3% or 66.8% BrdU-positive beta cells was detected in the young or old grafts, respectively. No statistic difference in the percent BrdU- or Ki67-positive beta cells was detected between the young and aged grafts at any time point studied. CONCLUSIONS These data reveal that islet beta cells from aged mice can replicate in response to hyperglycemia after transplantation at a capacity and frequencies not significantly different than that of the young adult ones.
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Andersson A, Carlsson PO, Carlsson C, Olsson R, Nordin A, Johansson M, Palm F, Tyrberg B, Källskog O, Tillmar L, Welsh N, Mattsson G, Jansson L. Promoting islet cell function after transplantation. Cell Biochem Biophys 2009; 40:55-64. [PMID: 15289643 DOI: 10.1385/cbb:40:3:55] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Engraftment (i.e., the adaptation of transplanted pancreatic islets to their new surroundings with regard to revascularization, reinnervation, and reorganization of other stromal compartments) is of crucial importance for the survival and function of the endocrine cells. Previous studies suggest that transplantation induces both vascular and stromal dysfunctions in the implanted islets when compared with endogenous islets. Thus the vascular density and the blood perfusion of islet grafts is decreased and accompanied with a capillary hypertension. This leads to hypoxic conditions, with an associated shift toward anaerobic metabolism in grafted islets. An improved engraftment will prevent or compensate for the vascular/stromal dysfunction seen in transplanted islets and thereby augment survival of the islet implant. By such means the number of islets needed to cure the recipient will be lessened. This will increase the number of patients that can be transplanted with the limited material available.
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Affiliation(s)
- Arne Andersson
- Department of Medical Cell Biology, Biomedical Centre, Uppsala University, Uppsala, Sweden.
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32
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Abstract
Transplantation of pancreatic islets offers a direct treatment for type 1 diabetes and in some cases, insulin-dependent type 2 diabetes. However, its widespread use is hampered by a shortage of donor organs. Many extant studies have focused on deriving beta-cell progenitors from pancreas and pluripotent stem cells. Efforts to generate beta-cells in vitro will help elucidate the mechanisms of beta-cell formation and thus provide a versatile in vivo system to evaluate the therapeutic potential of these cells to treat diabetes. Various successful experiments using beta-cells in animal models have generated extensive interest in using human embryonic stem cells to restore normoglycemia in diabetic patients. While new techniques are continually unveiled, the success of beta-cell generation rests upon successful manipulation of culture conditions and the induction of key regulatory genes implicated in pancreas development. In this review, we compare successfully conducted protocols, highlight essential steps and identify some of the remarkable shortfalls common to these methods. In addition, we discuss recent advancements in the derivation of patient-specific pluripotent stem cells that may facilitate the use of autologous beta-cells in stem cell therapy.
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Affiliation(s)
- Chee Gee Liew
- Sue and Bill Gross Stem Cell Research Center, 101 Theory, University of California, Irvine, California 92617, USA
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Carbonic anhydrase II-positive pancreatic cells are progenitors for both endocrine and exocrine pancreas after birth. Proc Natl Acad Sci U S A 2008; 105:19915-9. [PMID: 19052237 DOI: 10.1073/pnas.0805803105] [Citation(s) in RCA: 352] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The regenerative process in the pancreas is of particular interest because diabetes results from an inadequate number of insulin-producing beta cells and pancreatic cancer may arise from the uncontrolled growth of progenitor/stem cells. Continued and substantial growth of islet tissue occurs after birth in rodents and humans, with additional compensatory growth in response to increased demand. In rodents there is clear evidence of pancreatic regeneration after some types of injury, with proliferation of preexisting differentiated cell types accounting for some replacement. Additionally, neogenesis or the budding of new islet cells from pancreatic ducts has been reported, but the existence and identity of a progenitor cell have been debated. We hypothesized that the progenitor cells are duct epithelial cells that after replication undergo a regression to a less differentiated state and then can form new endocrine and exocrine pancreas. To directly test whether ductal cells serve as pancreatic progenitors after birth and give rise to new islets, we generated transgenic mice expressing human carbonic anhydrase II (CAII) promoter: Cre recombinase (Cre) or inducible CreER(TM) to cross with ROSA26 loxP-Stop-loxP LacZ reporter mice. We show that CAII-expressing cells within the pancreas act as progenitors that give rise to both new islets and acini normally after birth and after injury (ductal ligation). This identification of a differentiated pancreatic cell type as an in vivo progenitor of all differentiated pancreatic cell types has implications for a potential expandable source for new islets for replenishment therapy for diabetes.
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Otonkoski T, Banerjee M, Korsgren O, Thornell LE, Virtanen I. Unique basement membrane structure of human pancreatic islets: implications for beta-cell growth and differentiation. Diabetes Obes Metab 2008; 10 Suppl 4:119-27. [PMID: 18834439 DOI: 10.1111/j.1463-1326.2008.00955.x] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Basement membranes (BMs) are an important part of the physiological microenvironment of pancreatic islet cells. In mouse islets, beta-cells interact directly with BMs of capillary endothelial cells. We have shown that in the human islets, the capillaries are surrounded by a double BM both in foetal and adult tissues. The endocrine islet cells are facing a BM that is separate from the endothelia. Laminins are the functionally most important component of BMs. The only laminin isoform present in the human endocrine islet BM is laminin-511 (previously known as laminin 10). The islet cells facing this BM have a strong and polarized expression of Lutheran glycoprotein, which is a well-known receptor for the laminin alpha 5 chain. Dispersed human islet cells adhere to purified human laminin-511 and the binding is equally effectively blocked by a soluble form of Lutheran as by antibody against integrin beta1. Our results reveal unique features of the BM structure of human islets, different from rodents. This information has potentially important implications for the generation of an optimal microenvironment for beta-cell function, proliferation and differentiation.
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Affiliation(s)
- T Otonkoski
- Biomedicum Stem Cell Center and Hospital for Children and Adolescents, University of Helsinki, Helsinki, Finland.
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35
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Bonner-Weir S, Sharma A. Are there pancreatic progenitor cells from which new islets form after birth? ACTA ACUST UNITED AC 2007; 2:240-1. [PMID: 16932290 DOI: 10.1038/ncpendmet0186] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2005] [Accepted: 02/20/2006] [Indexed: 12/25/2022]
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Movassat J, Portha B. Models for pharmacological activation of beta-cell regeneration in diabetes. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.ddmod.2007.11.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Gao R, Ustinov J, Korsgren O, Mikkola M, Lundin K, Otonkoski T. Maturation of in vitro-generated human islets after transplantation in nude mice. Mol Cell Endocrinol 2007; 264:28-34. [PMID: 17116362 DOI: 10.1016/j.mce.2006.10.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2006] [Revised: 10/03/2006] [Accepted: 10/03/2006] [Indexed: 11/17/2022]
Abstract
The long-term function of human pancreatic islet grafts may depend on the neogenesis of beta cells from epithelial precursors within the grafted tissue. We have developed an in vitro model for human islet neogenesis. In this study, we have investigated the morphological signs of maturation in cultivated human islet buds (CHIBs) before and after transplantation. Clusterin is a molecule associated with beta-cell differentiation in rodents. In adult human islets, clusterin expression was located only in alpha- and PP-cells, but in CHIBs and human fetal islets, it was distributed in all four types of endocrine cells. Some immature endocrine cells in the CHIBs co-expressed insulin and glucagon. After transplantation, CHIBs became mature with one type of hormone per endocrine cell, and clusterin expression became restricted in alpha-cells. Cells co-expressing endocrine markers and cytokeratin 19, as a sign of ductal to endocrine cell transition, were frequently detected in both fresh islets and CHIBs after transplantation. We conclude that clusterin may be involved in the development of islets, and the in vitro-derived islets become mature after transplantation into nude mice. Ductal cell differentiation into endocrine cells may be an important factor in sustaining the long-term function of islet transplants.
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Affiliation(s)
- Ru Gao
- Program of Developmental and Reproductive Biology, Biomedicum Helsinki, University of Helsinki, Finland.
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Mussmann R, Geese M, Harder F, Kegel S, Andag U, Lomow A, Burk U, Onichtchouk D, Dohrmann C, Austen M. Inhibition of GSK3 promotes replication and survival of pancreatic beta cells. J Biol Chem 2007; 282:12030-7. [PMID: 17242403 DOI: 10.1074/jbc.m609637200] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Recent developments indicate that the regeneration of beta cell function and mass in patients with diabetes is possible. A regenerative approach may represent an alternative treatment option relative to current diabetes therapies that fail to provide optimal glycemic control. Here we report that the inactivation of GSK3 by small molecule inhibitors or RNA interference stimulates replication of INS-1E rat insulinoma cells. Specific and potent GSK3 inhibitors also alleviate the toxic effects of high concentrations of glucose and the saturated fatty acid palmitate on INS-1E cells. Furthermore, treatment of isolated rat islets with structurally diverse small molecule GSK3 inhibitors increases the rate beta cell replication by 2-3-fold relative to controls. We propose that GSK3 is a regulator of beta cell replication and survival. Moreover, our results suggest that specific inhibitors of GSK3 may have practical applications in beta cell regenerative therapies.
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Affiliation(s)
- Rainer Mussmann
- DeveloGen AG, Marie-Curie-Strasse 7, Göttingen 37079, Germany
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Gao R, Ustinov J, Korsgren O, Otonkoski T. In vitro neogenesis of human islets reflects the plasticity of differentiated human pancreatic cells. Diabetologia 2005; 48:2296-304. [PMID: 16193291 DOI: 10.1007/s00125-005-1935-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Accepted: 06/16/2005] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS The neogenesis of islets from cultured human adult pancreatic tissue has been reported. The islet progenitors have been thought to be ductal cells. Since previous experiments have been 'contaminated' by a number of pre-existing islet cells, we examined their involvement in islet cell neogenesis. METHODS Fresh human pancreatic cells with different purities of islet cells were grown in monolayer culture and labelled with bromodeoxyuridine. Transitional cells were analysed by double immunofluorescence staining. For purified ductal cell culture, pre-existing islets were eliminated on a magnetic cell separation system. RESULTS We confirmed that less than 1% of the endocrine cells proliferated, mainly during the first 48 h of culture. However, a 10-fold larger proportion of the cells acquired a transitional phenotype by starting to coexpress the ductal marker cytokeratin 19 (CK19). These cells represented more than 10% of all endocrine cells after 1 day in culture, and 6% at 5 days of culture. Using magnetic cell sorting, we eliminated cells expressing neural cell adhesion molecule (N-CAM), after which we obtained 99.7% pure non-endocrine CK19-rich cell populations. These cell populations could be expanded in vitro. However, their endocrine differentiation capacity was severely reduced as compared with the original mixed cell cultures. CONCLUSIONS/INTERPRETATION These results suggest that islet neogenesis in this culture system at least partly represents the de-differentiation of islet cells into a duct-cell-like phenotype, with further re-differentiation in appropriate conditions. The plasticity of differentiated human pancreatic cell types may thus be an important mechanism of human pancreas regeneration.
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Affiliation(s)
- R Gao
- Program of Developmental and Reproductive Biology, Biomedicum Helsinki, University of Helsinki, Finland.
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King A, Lock J, Xu G, Bonner-Weir S, Weir GC. Islet transplantation outcomes in mice are better with fresh islets and exendin-4 treatment. Diabetologia 2005; 48:2074-9. [PMID: 16132945 DOI: 10.1007/s00125-005-1922-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2005] [Accepted: 06/07/2005] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS Although islet transplantation in diabetes holds great promise, two or three donor pancreases are usually required to achieve normoglycaemia in human or rodent recipients. We investigated whether there were differences between fresh and cultured islets in terms of transplantation outcome. We also investigated the effects of normoglycaemia during engraftment and the effects of exendin-4, a glucagon-like peptide-1 receptor agonist, on islet transplantation. MATERIALS AND METHODS Seventy-five fresh islets were transplanted to the right kidney of diabetic mice and 425 fresh islets were transplanted to the left kidney. The mice were treated with exendin-4 or vehicle for 14 days, after which the large graft was removed by left nephrectomy. In a separate set of experiments, islets cultured in the presence or absence of exendin-4 for 72 h, or fresh islets, were transplanted to diabetic mice. In both sets of experiments, blood glucose levels were monitored. RESULTS Compared with cultured islets, fresh islets were more effective at reversing hyperglycaemia in mice. The treatment of the recipient mice with exendin-4 did not have beneficial effects on glucose homeostasis. However, when islets are cultured, exendin-4 treatment increases the rate of reversal of hyperglycaemia, but not to the degree of fresh islets. CONCLUSIONS/INTERPRETATION Fresh islets are more effective than cultured islets at reversing hyperglycaemia. Exendin-4 has beneficial effects on islet transplantation.
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Affiliation(s)
- A King
- Section on Islet Transplantation and Cell Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
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41
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Abstract
Two major initiatives are under way to correct the beta-cell deficit of diabetes: one would generate beta-cells ex vivo that are suitable for transplantation, and the second would stimulate regeneration of beta-cells in the pancreas. Studies of ex vivo expansion suggest that beta-cells have a potential for dedifferentiation, expansion, and redifferentiation. Work with mouse and human embryonic stem (ES) cells has not yet produced cells with the phenotype of true beta-cells, but there has been recent progress in directing ES cells to endoderm. Putative islet stem/progenitor cells have been identified in mouse pancreas, and formation of new beta-cells from duct, acinar and liver cells is an active area of investigation. Peptides, including glucagon-like peptide-1/exendin-4 and the combination of epidermal growth factor and gastrin, can stimulate regeneration of beta-cells in vivo. Recent progress in the search for new sources of beta-cells has opened promising new opportunities and spawned clinical trials.
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Affiliation(s)
- Susan Bonner-Weir
- Section of Islet Transplantation and Cell Biology, Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, Massachusetts 02215, USA.
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Suarez-Pinzon WL, Lakey JRT, Brand SJ, Rabinovitch A. Combination therapy with epidermal growth factor and gastrin induces neogenesis of human islet {beta}-cells from pancreatic duct cells and an increase in functional {beta}-cell mass. J Clin Endocrinol Metab 2005; 90:3401-9. [PMID: 15769977 DOI: 10.1210/jc.2004-0761] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Pancreatic islet transplantation is a viable treatment for type 1 diabetes, but is limited by human donor tissue availability. The combination of epidermal growth factor (EGF) and gastrin induces islet beta-cell neogenesis from pancreatic exocrine duct cells in rodents. In this study we investigated whether EGF and gastrin could expand the beta-cell mass in adult human isolated islets that contain duct as well as endocrine cells. Human islet cells were cultured for 4 wk in serum-free medium (control) or in medium with EGF (0.3 mug/ml), gastrin (1.0 mug/ml), or the combination of EGF and gastrin. beta-Cell numbers were increased in cultures with EGF plus gastrin (+118%) and with EGF (+81%), but not in cultures with gastrin (-3%) or control medium (-62%). After withdrawal of EGF and gastrin and an additional 4 wk in control medium, beta-cell numbers continued to increase only in cultures previously incubated with both EGF and gastrin (+232%). EGF plus gastrin also significantly increased cytokeratin 19-positive duct cells (+678%) in the cultures. Gastrin, alone or in combination with EGF, but not EGF alone, increased the expression of pancreatic and duodenal homeobox factor-1 as well as insulin and C peptide in the cytokeratin 19-positive duct cells. Also, EGF plus gastrin significantly increased beta-cells and insulin content in human islets implanted in immunodeficient nonobese diabetic-severe combined immune deficiency mice as well as insulin secretory responses of the human islet grafts to glucose challenge. In conclusion, combination therapy with EGF and gastrin increases beta-cell mass in adult human pancreatic islets in vitro and in vivo, and this appears to result from the induction of beta-cell neogenesis from pancreatic exocrine duct cells.
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Affiliation(s)
- Wilma L Suarez-Pinzon
- 430 Heritage Medical Research Center, University of Alberta, Edmonton, Alberta, Canada T6G 2S2
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Lee JA, Kim YK. Measurement of Age-Related Changes in Bone Matrix Using 2H 2O Labeling. Prev Nutr Food Sci 2005. [DOI: 10.3746/jfn.2005.10.1.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Abstract
Post-translational proteolytic processing of the preproglucagon gene in the gut results in the formation of glucagon-like peptide 1 (GLP-1). Owing to its glucose-dependent insulinotropic effect, this hormone was postulated to primarily act as an incretin, i.e. to augment insulin secretion after oral glucose or meal ingestion. In addition, GLP-1 decelerates gastric emptying and suppresses glucagon secretion. Under physiological conditions, GLP-1 acts as a part of the 'ileal brake', meaning that is slows the transition of nutrients into the distal gut. Animal studies suggest a role for GLP-1 in the development and growth of the endocrine pancreas. In light of its multiple actions throughout the body, different therapeutic applications of GLP-1 are possible. Promising results have been obtained with GLP-1 in the treatment of type 2 diabetes, but its potential to reduce appetite and food intake may also allow its use for the treatment of obesity. While rapid in vivo degradation of GLP-1 has yet prevented its broad clinical use, different pharmacological approaches aiming to extend the in vivo half-life of GLP-1 or to inhibit its inactivation are currently being evaluated. Therefore, antidiabetic treatment based on GLP-1 may become available within the next years. This review will summarize the biological effects of GLP-1, characterize its role in human biology and pathology, and discuss potential clinical applications as well as current clinical studies.
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Affiliation(s)
- Juris J Meier
- Larry L. Hillblom Islet Research Center, UCLA School of Medicine, Los Angeles, USA
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Abstract
Insufficient pancreatic beta-cell mass is fundamental to the pathogenesis of both types 1 and 2 diabetes and constitutes the basis for the goal of beta-cell replacement therapy. Current methods for isolating islets from organ donor pancreases do not come close to supplying all in need, thus providing a compelling need to find new sources of insulin-producing cells. Possible sources include generation of cells from embryonic stem cells (ESC), adult stem/precursor cells, transdifferentiation of other cell types and xenodonors. Bioengineering can be used to improve secretory performance and strengthen cells to better withstand the challenges of transplantation. Strategies include protection against hypoxia, inflammation, and immune attack.
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Affiliation(s)
- Gordon C Weir
- Section on Islet Transplantation and Cell Biology, Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA 02215, USA.
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Abstract
This article proposes five stages in the progression of diabetes, each of which is characterized by different changes in beta-cell mass, phenotype, and function. Stage 1 is compensation: insulin secretion increases to maintain normoglycemia in the face of insulin resistance and/or decreasing beta-cell mass. This stage is characterized by maintenance of differentiated function with intact acute glucose-stimulated insulin secretion (GSIS). Stage 2 occurs when glucose levels start to rise, reaching approximately 5.0-6.5 mmol/l; this is a stable state of beta-cell adaptation with loss of beta-cell mass and disruption of function as evidenced by diminished GSIS and beta-cell dedifferentiation. Stage 3 is a transient unstable period of early decompensation in which glucose levels rise relatively rapidly to the frank diabetes of stage 4, which is characterized as stable decompensation with more severe beta-cell dedifferentiation. Finally, stage 5 is characterized by severe decompensation representing a profound reduction in beta-cell mass with progression to ketosis. Movement across stages 1-4 can be in either direction. For example, individuals with treated type 2 diabetes can move from stage 4 to stage 1 or stage 2. For type 1 diabetes, as remission develops, progression from stage 4 to stage 2 is typically found. Delineation of these stages provides insight into the pathophysiology of both progression and remission of diabetes.
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Affiliation(s)
- Gordon C Weir
- Section on Islet Transplantation and Cell Biology, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA.
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Zhang H, Lu A, Zhao H, Li K, Song S, Yan J, Zhang W, Wang S, Li L. Elevation of NMDAR after transplantation of neural stem cells. Neuroreport 2004; 15:1739-43. [PMID: 15257139 DOI: 10.1097/01.wnr.0000131676.38437.2d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cognitive deficits could be alleviated by transplantation of neural stem cells in animals. Grafted cells may differentiate into neurons, thereby improving animal cognition. Alternatively, grafted cells may provide neurotrophic factors to modify neuronal functions and to alleviate cognitive deficits. To test which mechanism is underlying this recovery process, senescence-accelerated mice were transplanted with human neural stem cells into the hippocampus. The effect of cell transplantation was assessed in the Morris water maze. The survival and differentiation of grafted cells and the expression of NMDA receptors were examined. The data suggested that in addition to the neural differentiation of grafted neural stem cells, up-regulation of NMDA receptors after transplantation also contributed to the alleviation of cognitive deficits in this animal model.
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Affiliation(s)
- Huanqing Zhang
- Peking University Stem Cell Research Center, 38 Xueyuan Road, Beijing 100083, P.R. China
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Promoting islet cell function after transplantation. Cell Biochem Biophys 2004. [DOI: 10.1007/bf02739012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Butler AE, Janson J, Soeller WC, Butler PC. Increased beta-cell apoptosis prevents adaptive increase in beta-cell mass in mouse model of type 2 diabetes: evidence for role of islet amyloid formation rather than direct action of amyloid. Diabetes 2003; 52:2304-14. [PMID: 12941770 DOI: 10.2337/diabetes.52.9.2304] [Citation(s) in RCA: 296] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nondiabetic obese humans adapt to insulin resistance by increasing beta-cell mass. In contrast, obese humans with type 2 diabetes have an approximately 60% deficit in beta-cell mass. Recent studies in rodents reveal that beta-cell mass is regulated, increasing in response to insulin resistance through increased beta-cell supply (islet neogenesis and beta-cell replication) and/or decreased beta-cell loss (beta-cell apoptosis). Prospective studies of islet turnover are not possible in humans. In an attempt to establish the mechanism for the deficit in beta-cell mass in type 2 diabetes, we used an obese versus lean murine transgenic model for human islet amyloid polypeptide (IAPP) that develops islet pathology comparable to that in humans with type 2 diabetes. By 40 weeks of age, obese nontransgenic mice did not develop diabetes and adapted to insulin resistance by a 9-fold increase (P < 0.001) in beta-cell mass accomplished by a 1.7-fold increase in islet neogenesis (P < 0.05) and a 5-fold increase in beta-cell replication per islet (P < 0.001). Obese transgenic mice developed midlife diabetes with islet amyloid and an 80% (P < 0.001) deficit in beta-cell mass that was due to failure to adaptively increase beta-cell mass. The mechanism subserving this failed expansion was a 10-fold increase in beta-cell apoptosis (P < 0.001). There was no relationship between the extent of islet amyloid or the blood glucose concentration and the frequency of beta-cell apoptosis. However, the frequency of beta-cell apoptosis was related to the rate of increase of islet amyloid. These prospective studies suggest that the formation of islet amyloid rather than the islet amyloid per se is related to increased beta-cell apoptosis in this murine model of type 2 diabetes. This finding is consistent with the hypothesis that soluble IAPP oligomers but not islet amyloid are responsible for increased beta-cell apoptosis. The current studies also support the concept that replicating beta-cells are more vulnerable to apoptosis, possibly accounting for the failure of beta-cell mass to expand appropriately in response to obesity in type 2 diabetes.
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Affiliation(s)
- Alexandra E Butler
- Division of Endocrinology and Diabetes, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
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