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Chong ACN, Vandana JJ, Jeng G, Li G, Meng Z, Duan X, Zhang T, Qiu Y, Duran-Struuck R, Coker K, Wang W, Li Y, Min Z, Zuo X, de Silva N, Chen Z, Naji A, Hao M, Liu C, Chen S. Checkpoint kinase 2 controls insulin secretion and glucose homeostasis. Nat Chem Biol 2024; 20:566-576. [PMID: 37945898 PMCID: PMC11062908 DOI: 10.1038/s41589-023-01466-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 10/03/2023] [Indexed: 11/12/2023]
Abstract
After the discovery of insulin, a century ago, extensive work has been done to unravel the molecular network regulating insulin secretion. Here we performed a chemical screen and identified AZD7762, a compound that potentiates glucose-stimulated insulin secretion (GSIS) of a human β cell line, healthy and type 2 diabetic (T2D) human islets and primary cynomolgus macaque islets. In vivo studies in diabetic mouse models and cynomolgus macaques demonstrated that AZD7762 enhances GSIS and improves glucose tolerance. Furthermore, genetic manipulation confirmed that ablation of CHEK2 in human β cells results in increased insulin secretion. Consistently, high-fat-diet-fed Chk2-/- mice show elevated insulin secretion and improved glucose clearance. Finally, untargeted metabolic profiling demonstrated the key role of the CHEK2-PP2A-PLK1-G6PD-PPP pathway in insulin secretion. This study successfully identifies a previously unknown insulin secretion regulating pathway that is conserved across rodents, cynomolgus macaques and human β cells in both healthy and T2D conditions.
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Affiliation(s)
- Angie Chi Nok Chong
- Department of Surgery, Weill Cornell Medicine, New York City, NY, USA
- Center for Genomic Health, Weill Cornell Medicine, New York City, NY, USA
| | - J Jeya Vandana
- Department of Surgery, Weill Cornell Medicine, New York City, NY, USA
- Center for Genomic Health, Weill Cornell Medicine, New York City, NY, USA
- Tri-Institutional PhD Program in Chemical Biology, New York City, NY, USA
| | - Ginnie Jeng
- Department of Urology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ge Li
- Department of Medicine, Weill Cornell Medicine, New York City, NY, USA
- Department of Biological Sciences, Bronx Community College, City University of New York, Bronx, NY, USA
| | - Zihe Meng
- Department of Surgery, Weill Cornell Medicine, New York City, NY, USA
- Center for Genomic Health, Weill Cornell Medicine, New York City, NY, USA
| | - Xiaohua Duan
- Department of Surgery, Weill Cornell Medicine, New York City, NY, USA
- Center for Genomic Health, Weill Cornell Medicine, New York City, NY, USA
| | - Tuo Zhang
- Department of Microbiology and Immunology, Weill Cornell Medicine, New York City, NY, USA
| | - Yunping Qiu
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Raimon Duran-Struuck
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Kimberly Coker
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Wei Wang
- Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Yanjing Li
- Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Zaw Min
- Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Xi Zuo
- Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Neranjan de Silva
- Department of Surgery, Weill Cornell Medicine, New York City, NY, USA
| | - Zhengming Chen
- Department of Population Health Sciences, Weill Cornell Medicine, New York City, NY, USA
| | - Ali Naji
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Mingming Hao
- Department of Biochemistry, Weill Cornell Medicine, New York City, NY, USA
| | - Chengyang Liu
- Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
| | - Shuibing Chen
- Department of Surgery, Weill Cornell Medicine, New York City, NY, USA.
- Center for Genomic Health, Weill Cornell Medicine, New York City, NY, USA.
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Kara N, Ayoub N, Ilgu H, Fotiadis D, Ilgu M. Aptamers Targeting Membrane Proteins for Sensor and Diagnostic Applications. Molecules 2023; 28:molecules28093728. [PMID: 37175137 PMCID: PMC10180177 DOI: 10.3390/molecules28093728] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/07/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023] Open
Abstract
Many biological processes (physiological or pathological) are relevant to membrane proteins (MPs), which account for almost 30% of the total of human proteins. As such, MPs can serve as predictive molecular biomarkers for disease diagnosis and prognosis. Indeed, cell surface MPs are an important class of attractive targets of the currently prescribed therapeutic drugs and diagnostic molecules used in disease detection. The oligonucleotides known as aptamers can be selected against a particular target with high affinity and selectivity by iterative rounds of in vitro library evolution, known as Systematic Evolution of Ligands by EXponential Enrichment (SELEX). As an alternative to antibodies, aptamers offer unique features like thermal stability, low-cost, reuse, ease of chemical modification, and compatibility with various detection techniques. Particularly, immobilized-aptamer sensing platforms have been under investigation for diagnostics and have demonstrated significant value compared to other analytical techniques. These "aptasensors" can be classified into several types based on their working principle, which are commonly electrochemical, optical, or mass-sensitive. In this review, we review the studies on aptamer-based MP-sensing technologies for diagnostic applications and have included new methodological variations undertaken in recent years.
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Affiliation(s)
- Nilufer Kara
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
| | - Nooraldeen Ayoub
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
- Institute of Biochemistry and Molecular Medicine, University of Bern, CH-3012 Bern, Switzerland
| | - Huseyin Ilgu
- Institute of Biochemistry and Molecular Medicine, University of Bern, CH-3012 Bern, Switzerland
| | - Dimitrios Fotiadis
- Institute of Biochemistry and Molecular Medicine, University of Bern, CH-3012 Bern, Switzerland
| | - Muslum Ilgu
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA 50011, USA
- Aptalogic Inc., Ames, IA 50014, USA
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Wang H, Yuan YC, Chang C, Izumi T, Wang HH, Yang JK. The signaling protein GIV/Girdin mediates the Nephrin-dependent insulin secretion of pancreatic islet β cells in response to high glucose. J Biol Chem 2023; 299:103045. [PMID: 36822326 PMCID: PMC10040812 DOI: 10.1016/j.jbc.2023.103045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 02/10/2023] [Accepted: 02/12/2023] [Indexed: 02/23/2023] Open
Abstract
Glucose-stimulated insulin secretion of pancreatic β cells is essential in maintaining glucose homeostasis. Recent evidence suggests that the Nephrin-mediated intercellular junction between β cells is implicated in the regulation of insulin secretion. However, the underlying mechanisms are only partially characterized. Herein we report that GIV is a signaling mediator coordinating glucose-stimulated Nephrin phosphorylation and endocytosis with insulin secretion. We demonstrate that GIV is expressed in mouse islets and cultured β cells. The loss of function study suggests that GIV is essential for the second phase of glucose-stimulated insulin secretion. Next, we demonstrate that GIV mediates the high glucose-stimulated tyrosine phosphorylation of GIV and Nephrin by recruiting Src kinase, which leads to the endocytosis of Nephrin. Subsequently, the glucose-induced GIV/Nephrin/Src signaling events trigger downstream Akt phosphorylation, which activates Rac1-mediated cytoskeleton reorganization, allowing insulin secretory granules to access the plasma membrane for the second-phase secretion. Finally, we found that GIV is downregulated in the islets isolated from diabetic mice, and rescue of GIV ameliorates the β-cell dysfunction to restore the glucose-stimulated insulin secretion. We conclude that the GIV/Nephrin/Akt signaling axis is vital to regulate glucose-stimulated insulin secretion. This mechanism might be further targeted for therapeutic intervention of diabetic mellitus.
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Affiliation(s)
- Hao Wang
- Beijing Key Laboratory of Diabetes Research and Care, Beijing Diabetes Institute, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
| | - Ying-Chao Yuan
- Beijing Key Laboratory of Diabetes Research and Care, Beijing Diabetes Institute, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Cong Chang
- College of Biology, Hunan University, Changsha, Hunan, China; Hunan Food and Drug Vocational College, Changsha, Hunan, China
| | - Tetsuro Izumi
- Laboratory of Molecular Endocrinology and Metabolism, Department of Molecular Medicine, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, Japan
| | - Hong-Hui Wang
- College of Biology, Hunan University, Changsha, Hunan, China.
| | - Jin-Kui Yang
- Beijing Key Laboratory of Diabetes Research and Care, Beijing Diabetes Institute, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
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Zhang X, Zhu X, Bi X, Huang J, Zhou L. The Insulin Receptor: An Important Target for the Development of Novel Medicines and Pesticides. Int J Mol Sci 2022; 23:ijms23147793. [PMID: 35887136 PMCID: PMC9325136 DOI: 10.3390/ijms23147793] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/10/2022] [Accepted: 07/12/2022] [Indexed: 02/04/2023] Open
Abstract
The insulin receptor (IR) is a transmembrane protein that is activated by ligands in insulin signaling pathways. The IR has been considered as a novel therapeutic target for clinical intervention, considering the overexpression of its protein and A-isoform in multiple cancers, Alzheimer’s disease, and Type 2 diabetes mellitus in humans. Meanwhile, it may also serve as a potential target in pest management due to its multiple physiological influences in insects. In this review, we provide an overview of the structural and molecular biology of the IR, functions of IRs in humans and insects, physiological and nonpeptide small molecule modulators of the IR, and the regulating mechanisms of the IR. Xenobiotic compounds and the corresponding insecticidal chemicals functioning on the IR are also discussed. This review is expected to provide useful information for a better understanding of human IR-related diseases, as well as to facilitate the development of novel small-molecule activators and inhibitors of the IR for use as medicines or pesticides.
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Memon B, Younis I, Abubaker F, Abdelalim EM. PDX1 - /NKX6.1 + progenitors derived from human pluripotent stem cells as a novel source of insulin-secreting cells. Diabetes Metab Res Rev 2021; 37:e3400. [PMID: 32857429 DOI: 10.1002/dmrr.3400] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 12/11/2022]
Abstract
AIM Beta cell replacement strategies are a promising alternative for diabetes treatment. Human pluripotent stem cells (hPSCs) serve as a scalable source for producing insulin-secreting cells for transplantation therapy. We recently generated novel hPSC-derived pancreatic progenitors, expressing high levels of the transcription factor NKX6.1, in the absence of PDX1 (PDX1- /NKX6.1+ ). Herein, our aim was to characterize this novel population and assess its ability to differentiate into insulin-secreting beta cells in vitro. MATERIALS AND METHODS Three different hPSC lines were differentiated into PDX1- /NKX6.1+ progenitors, which were further differentiated into insulin-secreting cells using two different protocols. The progenitors and beta cells were extensively characterized. Transcriptome analysis was performed at different stages and compared with the profiles of various pancreatic counterparts. RESULTS PDX1- /NKX6.1+ progenitors expressed high levels of nestin, a key marker of pancreatic islet-derived progenitors, in the absence of E-cadherin, similar to pancreatic mesenchymal stem cells. At progenitor stage, comparison of the two populations showed downregulation of pancreatic epithelial genes and upregulation of neuronal development genes in PDX1- /NKX6.1+ cells in comparison to the PDX1+ /NKX6.1+ cells. Interestingly, on further differentiation, PDX1- /NKX6.1+ cells generated mono-hormonal insulin+ cells and activated pancreatic key genes, such as PDX1. The transcriptome profile of PDX1- /NKX6.1+ -derived beta (3D-beta) was closely similar to those of human pancreatic islets and purified hPSC-derived beta cells. Also, the 3D-beta cells secreted C-peptide in response to increased glucose concentrations indicating their functionality. CONCLUSION These findings provide a novel source of insulin-secreting cells that can be used for beta cell therapy for diabetes.
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Affiliation(s)
- Bushra Memon
- College of Health and Life Sciences (CHLS), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, Qatar
- Diabetes Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, PO Box 34110,, Qatar
| | - Ihab Younis
- Biological Sciences Program, Carnegie Mellon University in Qatar, Qatar Foundation (QF), Doha, Qatar
| | - Fadhil Abubaker
- Qatar Computing Research Institute (QCRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, Qatar
| | - Essam M Abdelalim
- College of Health and Life Sciences (CHLS), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, Qatar
- Diabetes Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, PO Box 34110,, Qatar
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Negi P, Cheke RS, Patil VM. Recent advances in pharmacological diversification of Src family kinase inhibitors. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2021. [DOI: 10.1186/s43042-021-00172-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Abstract
Background
Src kinase, a nonreceptor protein-tyrosine kinase is composed of 11 members (in human) and is involved in a wide variety of essential functions required to sustain cellular homeostasis and survival.
Main body of the abstract
Deregulated activity of Src family kinase is related to malignant transformation. In 2001, Food and Drug Administration approved imatinib for the treatment of chronic myeloid leukemia followed by approval of various other inhibitors from this category as effective therapeutics for cancer patients. In the past decade, Src family kinase has been investigated for the treatment of diverse pathologies in addition to cancer. In this regard, we provide a systematic evaluation of Src kinase regarding its mechanistic role in cancer and other diseases. Here we comment on preclinical and clinical success of Src kinase inhibitors in cancer followed by diabetes, hypertension, tuberculosis, and inflammation.
Short conclusion
Studies focusing on the diversified role of Src kinase as potential therapeutical target for the development of medicinally active agents might produce significant advances in the management of not only various types of cancer but also other diseases which are in demand for potent and safe therapeutics.
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Xu YF, Chen X, Yang Z, Xiao P, Liu CH, Li KS, Yang XZ, Wang YJ, Zhu ZL, Xu ZG, Zhang S, Wang C, Song YC, Zhao WD, Wang CH, Ji ZL, Zhang ZY, Cui M, Sun JP, Yu X. PTP-MEG2 regulates quantal size and fusion pore opening through two distinct structural bases and substrates. EMBO Rep 2021; 22:e52141. [PMID: 33764618 DOI: 10.15252/embr.202052141] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 01/26/2021] [Accepted: 02/18/2021] [Indexed: 02/02/2023] Open
Abstract
Tyrosine phosphorylation of secretion machinery proteins is a crucial regulatory mechanism for exocytosis. However, the participation of protein tyrosine phosphatases (PTPs) in different exocytosis stages has not been defined. Here we demonstrate that PTP-MEG2 controls multiple steps of catecholamine secretion. Biochemical and crystallographic analyses reveal key residues that govern the interaction between PTP-MEG2 and its substrate, a peptide containing the phosphorylated NSF-pY83 site, specify PTP-MEG2 substrate selectivity, and modulate the fusion of catecholamine-containing vesicles. Unexpectedly, delineation of PTP-MEG2 mutants along with the NSF binding interface reveals that PTP-MEG2 controls the fusion pore opening through NSF independent mechanisms. Utilizing bioinformatics search and biochemical and electrochemical screening approaches, we uncover that PTP-MEG2 regulates the opening and extension of the fusion pore by dephosphorylating the DYNAMIN2-pY125 and MUNC18-1-pY145 sites. Further structural and biochemical analyses confirmed the interaction of PTP-MEG2 with MUNC18-1-pY145 or DYNAMIN2-pY125 through a distinct structural basis compared with that of the NSF-pY83 site. Our studies thus provide mechanistic insights in complex exocytosis processes.
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Affiliation(s)
- Yun-Fei Xu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China.,Department of General Surgery, Qilu Hospital of Shandong University, Jinan, China
| | - Xu Chen
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, Shandong University School of Medicine, Jinan, China
| | - Zhao Yang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Peng Xiao
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Chun-Hua Liu
- Department of Physiology, Shandong First Medical University, Taian, China
| | - Kang-Shuai Li
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China.,Department of General Surgery, Qilu Hospital of Shandong University, Jinan, China
| | - Xiao-Zhen Yang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, China
| | - Yi-Jing Wang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Zhong-Liang Zhu
- School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Zhi-Gang Xu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, China
| | - Sheng Zhang
- Departments of Medicinal Chemistry and Molecular Pharmacology and of Chemistry, Center for Cancer Research, and Institute for Drug Discovery, Purdue University, West Lafayette, IN, USA
| | - Chuan Wang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China
| | - You-Chen Song
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Wei-Dong Zhao
- Department of Developmental Cell Biology, China Medical University, Shenyang, China
| | - Chang-He Wang
- Center for Mitochondrial Biology and Medicine, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Zhi-Liang Ji
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, China
| | - Zhong-Yin Zhang
- Departments of Medicinal Chemistry and Molecular Pharmacology and of Chemistry, Center for Cancer Research, and Institute for Drug Discovery, Purdue University, West Lafayette, IN, USA
| | - Min Cui
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, Shandong University School of Medicine, Jinan, China
| | - Jin-Peng Sun
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, Shandong University School of Medicine, Jinan, China
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Oakie A, Feng ZC, Li J, Silverstein J, Yee SP, Wang R. Long-term c-Kit overexpression in beta cells compromises their function in ageing mice. Diabetologia 2019; 62:1430-1444. [PMID: 31154478 DOI: 10.1007/s00125-019-4890-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 04/04/2019] [Indexed: 12/23/2022]
Abstract
AIMS/HYPOTHESIS c-Kit signalling regulates intracellular pathways that enhance beta cell proliferation, insulin secretion and islet vascularisation in mice up to 28 weeks of age and on short-term high-fat diet. However, long-term c-Kit activation in ageing mouse islets has yet to be examined. This study utilises beta cell-specific c-Kit-overexpressing transgenic (c-KitβTg) ageing mice (~60 weeks) to determine the effect of its activation on beta cell dysfunction and insulin secretion. METHODS Wild-type and c-KitβTg mice, aged 60 weeks, were examined using metabolic tests to determine glucose tolerance and insulin secretion. Pancreas histology and proteins in isolated islets were examined to determine the expression of beta cell transcription factors, proliferation and intracellular signalling. To determine the role of insulin receptor signalling in ageing c-KitβTg mice, we generated beta cell-specific inducible insulin receptor knockout in ageing c-KitβTg mice (c-KitβTg;βIRKO mice) and examined the ageing mice for glucose tolerance and islet histology. RESULTS Ageing c-KitβTg mice progressively developed glucose intolerance, compared with age-matched wild-type littermates, due to impaired insulin secretion. Increased beta cell mass, proliferation and nuclear forkhead box transcription factor O1 (FOXO1) expression and reduced exocytotic protein levels were detected in ageing c-KitβTg mouse islets. Protein analyses of isolated islets showed increased insulin receptor, phosphorylated IRS-1Ser612 and cleaved poly(ADP-ribose) polymerase levels in ageing c-KitβTg mice. Ageing c-KitβTg mouse islets treated ex vivo with insulin demonstrated reduced Akt phosphorylation, indicating that prolonged c-Kit induced beta cell insulin insensitivity. Ageing c-KitβTg;βIRKO mice displayed improved glucose tolerance and beta cell function compared with ageing c-KitβTg mice. CONCLUSIONS/INTERPRETATION These findings indicate that long-term c-Kit overexpression in beta cells has a negative impact on insulin exocytosis and that temporally dependent regulation of c-Kit-insulin receptor signalling is important for optimal beta cell function.
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Affiliation(s)
- Amanda Oakie
- Children's Health Research Institute, University of Western Ontario, Victoria Research Laboratories, Room A5-140, 800 Commissioners Road East, London, ON, N6C 2V5, Canada
- Department of Pathology and Laboratory Medicine, University of Western Ontario, London, ON, Canada
| | - Zhi-Chao Feng
- Children's Health Research Institute, University of Western Ontario, Victoria Research Laboratories, Room A5-140, 800 Commissioners Road East, London, ON, N6C 2V5, Canada
| | - Jinming Li
- Children's Health Research Institute, University of Western Ontario, Victoria Research Laboratories, Room A5-140, 800 Commissioners Road East, London, ON, N6C 2V5, Canada
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | - Jenna Silverstein
- Children's Health Research Institute, University of Western Ontario, Victoria Research Laboratories, Room A5-140, 800 Commissioners Road East, London, ON, N6C 2V5, Canada
| | - Siu-Pok Yee
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT, USA
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, CT, USA
| | - Rennian Wang
- Children's Health Research Institute, University of Western Ontario, Victoria Research Laboratories, Room A5-140, 800 Commissioners Road East, London, ON, N6C 2V5, Canada.
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.
- Department of Medicine, University of Western Ontario, London, ON, Canada.
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