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Stamateris RE, Landa-Galvan HV, Sharma RB, Darko C, Redmond D, Rane SG, Alonso LC. Noncanonical CDK4 signaling rescues diabetes in a mouse model by promoting β cell differentiation. J Clin Invest 2023; 133:e166490. [PMID: 37712417 PMCID: PMC10503800 DOI: 10.1172/jci166490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 07/27/2023] [Indexed: 09/16/2023] Open
Abstract
Expanding β cell mass is a critical goal in the fight against diabetes. CDK4, an extensively characterized cell cycle activator, is required to establish and maintain β cell number. β cell failure in the IRS2-deletion mouse type 2 diabetes model is, in part, due to loss of CDK4 regulator cyclin D2. We set out to determine whether replacement of endogenous CDK4 with the inhibitor-resistant mutant CDK4-R24C rescued the loss of β cell mass in IRS2-deficient mice. Surprisingly, not only β cell mass but also β cell dedifferentiation was effectively rescued, despite no improvement in whole body insulin sensitivity. Ex vivo studies in primary islet cells revealed a mechanism in which CDK4 intervened downstream in the insulin signaling pathway to prevent FOXO1-mediated transcriptional repression of critical β cell transcription factor Pdx1. FOXO1 inhibition was not related to E2F1 activity, to FOXO1 phosphorylation, or even to FOXO1 subcellular localization, but rather was related to deacetylation and reduced FOXO1 abundance. Taken together, these results demonstrate a differentiation-promoting activity of the classical cell cycle activator CDK4 and support the concept that β cell mass can be expanded without compromising function.
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Affiliation(s)
- Rachel E. Stamateris
- MD/PhD Program, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Huguet V. Landa-Galvan
- Division of Endocrinology, Diabetes and Metabolism and the Joan and Sanford I. Weill Center for Metabolic Health and
| | - Rohit B. Sharma
- Division of Endocrinology, Diabetes and Metabolism and the Joan and Sanford I. Weill Center for Metabolic Health and
| | - Christine Darko
- Division of Endocrinology, Diabetes and Metabolism and the Joan and Sanford I. Weill Center for Metabolic Health and
| | - David Redmond
- Hartman Institute for Therapeutic Regenerative Medicine, Division of Regenerative Medicine, Department of Medicine, Weill Cornell Medicine, New York, New York, USA
| | - Sushil G. Rane
- Integrative Cellular Metabolism Section, Diabetes, Endocrinology and Obesity Branch, National Institute for Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Laura C. Alonso
- Division of Endocrinology, Diabetes and Metabolism and the Joan and Sanford I. Weill Center for Metabolic Health and
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Yin Y, Tan M, Han L, Zhang L, Zhang Y, Zhang J, Pan W, Bai J, Jiang T, Li H. The hippo kinases MST1/2 in cardiovascular and metabolic diseases: A promising therapeutic target option for pharmacotherapy. Acta Pharm Sin B 2023; 13:1956-1975. [PMID: 37250161 PMCID: PMC10213817 DOI: 10.1016/j.apsb.2023.01.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 09/09/2022] [Accepted: 11/18/2022] [Indexed: 02/05/2023] Open
Abstract
Cardiovascular diseases (CVDs) and metabolic disorders are major components of noncommunicable diseases, causing an enormous health and economic burden worldwide. There are common risk factors and developmental mechanisms among them, indicating the far-reaching significance in exploring the corresponding therapeutic targets. MST1/2 kinases are well-established proapoptotic effectors that also bidirectionally regulate autophagic activity. Recent studies have demonstrated that MST1/2 influence the outcome of cardiovascular and metabolic diseases by regulating immune inflammation. In addition, drug development against them is in full swing. In this review, we mainly describe the roles and mechanisms of MST1/2 in apoptosis and autophagy in cardiovascular and metabolic events as well as emphasis on the existing evidence for their involvement in immune inflammation. Moreover, we summarize the latest progress of pharmacotherapy targeting MST1/2 and propose a new mode of drug combination therapy, which may be beneficial to seek more effective strategies to prevent and treat CVDs and metabolic disorders.
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Affiliation(s)
- Yunfei Yin
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Mingyue Tan
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Lianhua Han
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Lei Zhang
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Yue Zhang
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Jun Zhang
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Wanqian Pan
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Jiaxiang Bai
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
- Department of Orthopedics, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
- Department of Orthopedics, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230001, China
| | - Tingbo Jiang
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Hongxia Li
- Department of Cardiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China
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Kim HS, Lee D, Seo YH, Ryu SM, Lee AY, Moon BC, Kim WJ, Kang KS, Lee J. Chemical Constituents from the Roots of Angelica reflexa That Improve Glucose-Stimulated Insulin Secretion by Regulating Pancreatic β-Cell Metabolism. Pharmaceutics 2023; 15:pharmaceutics15041239. [PMID: 37111724 PMCID: PMC10146581 DOI: 10.3390/pharmaceutics15041239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 04/07/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
The aim of this study was to discover bioactive constituents of Angelica reflexa that improve glucose-stimulated insulin secretion (GSIS) in pancreatic β-cells. Herein, three new compounds, namely, koseonolin A (1), koseonolin B (2), and isohydroxylomatin (3), along with 28 compounds (4-31) were isolated from the roots of A. reflexa by chromatographic methods. The chemical structures of new compounds (1-3) were elucidated through spectroscopic/spectrometric methods such as NMR and HRESIMS. In particular, the absolute configuration of the new compounds (1 and 3) was performed by electronic circular dichroism (ECD) studies. The effects of the root extract of A. reflexa (KH2E) and isolated compounds (1-31) on GSIS were detected by GSIS assay, ADP/ATP ratio assay, and Western blot assay. We observed that KH2E enhanced GSIS. Among the compounds 1-31, isohydroxylomatin (3), (-)-marmesin (17), and marmesinin (19) increased GSIS. In particular, marmesinin (19) was the most effective; this effect was superior to treatment with gliclazide. GSI values were: 13.21 ± 0.12 and 7.02 ± 0.32 for marmesinin (19) and gliclazide at a same concentration of 10 μM, respectively. Gliclazide is often performed in patients with type 2 diabetes (T2D). KH2E and marmesinin (19) enhanced the protein expressions associated with pancreatic β-cell metabolism such as peroxisome proliferator-activated receptor γ, pancreatic and duodenal homeobox 1, and insulin receptor substrate-2. The effect of marmesinin (19) on GSIS was improved by an L-type Ca2+ channel agonist and K+ channel blocker and was inhibited by an L-type Ca2+ channel blocker and K+ channel activator. Marmesinin (19) may improve hyperglycemia by enhancing GSIS in pancreatic β-cells. Thus, marmesinin (19) may have potential use in developing novel anti-T2D therapy. These findings promote the potential application of marmesinin (19) toward the management of hyperglycemia in T2D.
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Affiliation(s)
- Hyo-Seon Kim
- Herbal Medicine Resources Research Center, Korea Institute of Oriental Medicine (KIOM), Naju 58245, Republic of Korea
| | - Dahae Lee
- Cooperative-Center of Natural Product Central Bank for Biological Evaluation, College of Korean Medicine, Gachon University, Seongnam 13120, Republic of Korea
| | - Young-Hye Seo
- Herbal Medicine Resources Research Center, Korea Institute of Oriental Medicine (KIOM), Naju 58245, Republic of Korea
| | - Seung-Mok Ryu
- Herbal Medicine Resources Research Center, Korea Institute of Oriental Medicine (KIOM), Naju 58245, Republic of Korea
| | - A-Yeong Lee
- Herbal Medicine Resources Research Center, Korea Institute of Oriental Medicine (KIOM), Naju 58245, Republic of Korea
| | - Byeong-Cheol Moon
- Herbal Medicine Resources Research Center, Korea Institute of Oriental Medicine (KIOM), Naju 58245, Republic of Korea
| | - Wook-Jin Kim
- Herbal Medicine Resources Research Center, Korea Institute of Oriental Medicine (KIOM), Naju 58245, Republic of Korea
| | - Ki-Sung Kang
- Cooperative-Center of Natural Product Central Bank for Biological Evaluation, College of Korean Medicine, Gachon University, Seongnam 13120, Republic of Korea
| | - Jun Lee
- Herbal Medicine Resources Research Center, Korea Institute of Oriental Medicine (KIOM), Naju 58245, Republic of Korea
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4
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Molecular dissection of cellular response of pancreatic islet cells to Bisphenol-A (BPA): a comprehensive review. Biochem Pharmacol 2022; 201:115068. [DOI: 10.1016/j.bcp.2022.115068] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/11/2022] [Accepted: 04/25/2022] [Indexed: 12/15/2022]
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5
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Asrih M, Dusaulcy R, Gosmain Y, Philippe J, Somm E, Jornayvaz FR, Kang BE, Jo Y, Choi MJ, Yi HS, Ryu D, Gariani K. Growth differentiation factor-15 prevents glucotoxicity and connexin-36 downregulation in pancreatic beta-cells. Mol Cell Endocrinol 2022; 541:111503. [PMID: 34763008 DOI: 10.1016/j.mce.2021.111503] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 10/26/2021] [Accepted: 10/29/2021] [Indexed: 01/11/2023]
Abstract
Pancreatic beta cell dysfunction is a hallmark of type 2 diabetes. Growth differentiation factor 15 (GDF15), which is an energy homeostasis regulator, has been shown to improve several metabolic parameters in the context of diabetes. However, its effects on pancreatic beta-cell remain to be identified. We, therefore, performed experiments using cell models and histological sectioning of wild-type and knock-out GDF15 mice to determine the effect of GDF15 on insulin secretion and cell viability. A bioinformatics analysis was performed to identify GDF15-correlated genes. GDF15 prevents glucotoxicity-mediated altered glucose-stimulated insulin secretion (GSIS) and connexin-36 downregulation. Inhibition of endogenous GDF15 reduced GSIS in cultured mouse beta-cells under standard conditions while it had no impact on GSIS in cells exposed to glucolipotoxicity, which is a diabetogenic condition. Furthermore, this inhibition exacerbated glucolipotoxicity-reduced cell survival. This suggests that endogenous GDF15 in beta-cell is required for cell survival but not GSIS in the context of glucolipotoxicity.
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Affiliation(s)
- Mohamed Asrih
- Service of Endocrinology, Diabetes, Nutrition and Patient Therapeutic Education, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland; University of Geneva Medical School, 1211, Geneva, Switzerland
| | - Rodolphe Dusaulcy
- Service of Endocrinology, Diabetes, Nutrition and Patient Therapeutic Education, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland; University of Geneva Medical School, 1211, Geneva, Switzerland
| | - Yvan Gosmain
- Service of Endocrinology, Diabetes, Nutrition and Patient Therapeutic Education, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland; University of Geneva Medical School, 1211, Geneva, Switzerland
| | - Jacques Philippe
- Service of Endocrinology, Diabetes, Nutrition and Patient Therapeutic Education, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland; University of Geneva Medical School, 1211, Geneva, Switzerland
| | - Emmanuel Somm
- Service of Endocrinology, Diabetes, Nutrition and Patient Therapeutic Education, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland; University of Geneva Medical School, 1211, Geneva, Switzerland
| | - François R Jornayvaz
- Service of Endocrinology, Diabetes, Nutrition and Patient Therapeutic Education, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland; University of Geneva Medical School, 1211, Geneva, Switzerland
| | - Baeki E Kang
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, 16419, Suwon, Republic of Korea
| | - Yunju Jo
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, 16419, Suwon, Republic of Korea
| | - Min Jeong Choi
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University Hospital, Chungnam National University School of Medicine, 35015, Daejeon, Republic of Korea; Department of Medical Science, Chungnam National University School of Medicine, 35015, Daejeon, Republic of Korea
| | - Hyon-Seung Yi
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University Hospital, Chungnam National University School of Medicine, 35015, Daejeon, Republic of Korea; Department of Medical Science, Chungnam National University School of Medicine, 35015, Daejeon, Republic of Korea
| | - Dongryeol Ryu
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, 16419, Suwon, Republic of Korea; Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, 16419, Suwon, Republic of Korea; Samsung Biomedical Research Institute, Samsung Medical Center, 06351, Seoul, Republic of Korea
| | - Karim Gariani
- Service of Endocrinology, Diabetes, Nutrition and Patient Therapeutic Education, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland; University of Geneva Medical School, 1211, Geneva, Switzerland.
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6
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HDL and Diabetes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1377:119-127. [DOI: 10.1007/978-981-19-1592-5_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Jiang Y, Zhu L, Wu D, Ni Y, Huang C, Ye H, Yang Y, Liu R, Li Y. Type IIB PKA is highly expressed in β cells and controls cell proliferation via regulating Cyclin D1 expression. FEBS J 2021; 289:2865-2876. [PMID: 34839588 DOI: 10.1111/febs.16302] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/09/2021] [Accepted: 11/26/2021] [Indexed: 12/01/2022]
Abstract
β cell number is maintained mainly by cell proliferation and cell apoptosis. Protein kinase A (PKA) pathway is an important intracellular signalling-mediating β cell proliferation. However, the precise roles of PKA isoforms are not well-defined. We found that the RIIB subunit of PKA is expressed specifically by β cells of mouse and human islets. Sixty percent pancreatectomy caused increased β cell proliferation. Deletion of type IIB PKA by disruption of RIIB expression further promoted β cell proliferation, leading to enhanced β cell mass expansion. RIIB KO mice also showed increased insulin levels and improved glucose tolerance. Mechanistically, activation of type IIB PKA decreased Cyclin D1 levels and inhibition of RIIB expression increased Cyclin D1 levels. Consistently, activation of type IIB PKA inhibited cell cycle entry. These results suggest that type IIB PKA plays a pivotal role in β cell proliferation via regulating Cyclin D1 expression.
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Affiliation(s)
- Yaojing Jiang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Lu Zhu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Di Wu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Yunzhi Ni
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Chuxin Huang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Hongying Ye
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Yehong Yang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Rui Liu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
| | - Yiming Li
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai, China
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Lee D, Qi Y, Kim R, Song J, Kim H, Kim HY, Jang DS, Kang KS. Methyl Caffeate Isolated from the Flowers of Prunus persica (L.) Batsch Enhances Glucose-Stimulated Insulin Secretion. Biomolecules 2021; 11:biom11020279. [PMID: 33672801 PMCID: PMC7917615 DOI: 10.3390/biom11020279] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 02/03/2023] Open
Abstract
Phenolic compounds from natural products are considered effective enhancers of insulin secretion to prevent and treat type 2 diabetes (T2DM). The flowers of Prunus persica (L.) Batsch also contain many phenolic compounds. In this study, the extract of flowers of P. persica (PRPE) exhibited an insulin secretion effect in a glucose-stimulated insulin secretion (GSIS) assay, which led us to isolate and identify the bioactive compound(s) responsible for these effects. Compounds isolated from PRPE were screened for their efficacy in INS-1 rat pancreatic β-cells. Among them, caffeic acid (5), methyl caffeate (6), ferulic acid (7), chlorogenic acid (8), naringenin (11), nicotiflorin (12), and astragalin (13) isolated from PRPE increased GSIS without inducing cytotoxicity. Interestingly, the GSIS effect of methyl caffeate (6) as a phenolic compound was similar to gliclazide, an antidiabetic sulfonylurea drug. Western blot assay showed that methyl caffeate (6) enhanced the related signaling proteins of the activated pancreatic and duodenal homeobox-1 (PDX-1) and peroxisome proliferator-activated receptor-γ (PPAR-γ), but also the phosphorylation of the total insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3-kinase (PI3K), and Akt, which influence β-cell function and insulin secretion. This study provides evidence that methyl caffeate (6) isolated from PRPE may aid in the management of T2DM.
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Affiliation(s)
- Dahae Lee
- College of Korean Medicine, Gachon University, Seongnam 13120, Korea;
| | - Yutong Qi
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Korea; (Y.Q.); (R.K.)
| | - Ranhee Kim
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Korea; (Y.Q.); (R.K.)
| | - Jungbin Song
- Department of Herbal Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea; (J.S.); (H.K.)
| | - Hocheol Kim
- Department of Herbal Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea; (J.S.); (H.K.)
| | - Hyun Young Kim
- Department of Food Science, Gyeongnam National University of Science and Technology, Jinju 52725, Korea;
| | - Dae Sik Jang
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Korea; (Y.Q.); (R.K.)
- Correspondence: (D.S.J.); (K.S.K.); Tel.: +82-2-961-0719 (D.S.J.); +82-31-750-5402 (K.S.K.)
| | - Ki Sung Kang
- College of Korean Medicine, Gachon University, Seongnam 13120, Korea;
- Correspondence: (D.S.J.); (K.S.K.); Tel.: +82-2-961-0719 (D.S.J.); +82-31-750-5402 (K.S.K.)
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Pereira de Arruda EH, Vieira da Silva GL, da Rosa-Santos CA, Arantes VC, de Barros Reis MA, Colodel EM, Gaspar de Moura E, Lisboa PC, Carneiro EM, Damazo AS, Latorraca MQ. Protein restriction during pregnancy impairs intra-islet GLP-1 and the expansion of β-cell mass. Mol Cell Endocrinol 2020; 518:110977. [PMID: 32791189 DOI: 10.1016/j.mce.2020.110977] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 07/14/2020] [Accepted: 08/03/2020] [Indexed: 12/26/2022]
Abstract
We evaluated whether protein restriction during pregnancy alters the morphometry of pancreatic islets, the intra-islet glucagon-like peptide-1 (GLP-1) production, and the anti-apoptotic signalling pathway modulated by GLP-1. Control non-pregnant (CNP) and control pregnant (CP) rats were fed a 17% protein diet, and low-protein non-pregnant (LPNP) and low-protein pregnant (LPP) groups were fed a 6% protein diet. The masses of islets and β-cells were similar in the LPNP group and the CNP group but were higher in the CP group than in the CNP group and were equal in the LPP group and the LPNP group. Both variables were lower in the LPP group than in the CP group. Prohormone convertase 2 and GLP-1 fluorescence in α-cells was lower in the low-protein groups than in the control groups. The least PC2/glucagon colocalization was observed in the LPP group, and the most was observed in the CP group. There was less prohormone convertase 1/3/glucagon colocalization in the LPP group than in the CP group. GLP-1/glucagon colocalization was similar in the LPP, CP and CNP groups, which showed less GLP-1/glucagon colocalization than the LPNP group. The mRNA Pka, Creb and Pdx-1 contents were higher in islets from pregnant rats than in islets from non-pregnant rats. Protein restriction during pregnancy impaired the mass of β-cells and the intra-islet GLP-1 production but did not interfere with the transcription of genes of the anti-apoptotic signalling pathway modulated by GLP-1.
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Affiliation(s)
| | | | - Chaiane Aline da Rosa-Santos
- Mestrado em Nutrição, Alimentos e Metabolismo, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil
| | - Vanessa Cristina Arantes
- Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil
| | | | - Edson Moleta Colodel
- Departamento de Clínica Médica Veterinária, Faculdade de Agronomia e Medicina Veterinária, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil
| | - Egberto Gaspar de Moura
- Laboratório de Fisiologia Endócrina, Departamento de Ciências Fisiológicas, Instituto de Biologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Patrícia Cristina Lisboa
- Laboratório de Fisiologia Endócrina, Departamento de Ciências Fisiológicas, Instituto de Biologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Everardo Magalhães Carneiro
- Departamento de Anatomia, Biologia Cellular, Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Amílcar Sabino Damazo
- Departamento de Ciências Básicas da Saúde, Faculdade de Medicina, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil
| | - Márcia Queiroz Latorraca
- Departamento de Alimentos e Nutrição, Faculdade de Nutrição, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil.
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10
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Chen C, Shiota C, Agostinelli G, Ridley D, Jiang Y, Ma J, Prasadan K, Xiao X, Gittes GK. Evidence of a developmental origin for β-cell heterogeneity using a dual lineage-tracing technology. Development 2019; 146:dev.164913. [PMID: 31160417 DOI: 10.1242/dev.164913] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 05/23/2019] [Indexed: 12/24/2022]
Abstract
The Cre/loxP system has been used extensively in mouse models with a limitation of one lineage at a time. Differences in function and other properties among populations of adult β-cells is termed β-cell heterogeneity, which was recently associated with diabetic phenotypes. Nevertheless, the presence of a developmentally derived β-cell heterogeneity is unclear. Here, we have developed a novel dual lineage-tracing technology, using a combination of two recombinase systems, Dre/RoxP and Cre/LoxP, to independently trace green fluorescent Pdx1-lineage cells and red fluorescent Ptf1a-lineage cells in the developing and adult mouse pancreas. We detected a few Pdx1+/Ptf1a- lineage cells in addition to the vast majority of Pdx1+/Ptf1a+ lineage cells in the pancreas. Moreover, Pdx1+/Ptf1a+ lineage β-cells had fewer Ki-67+ proliferating β-cells, and expressed higher mRNA levels of insulin, Glut2, Pdx1, MafA and Nkx6.1, but lower CCND1 and CDK4 levels, compared with Pdx1+/Ptf1a- lineage β-cells. Furthermore, more TSQ-high, SSC-high cells were detected in the Pdx1+Ptf1a+ lineage population than in the Pdx1+Ptf1a- lineage population. Together, these data suggest that differential activation of Ptf1a in the developing pancreas may correlate with this β-cell heterogeneity.
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Affiliation(s)
- Congde Chen
- Department of Pediatric Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, China.,Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Chiyo Shiota
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA.,Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Guy Agostinelli
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Daniel Ridley
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Yinan Jiang
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Jie Ma
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Krishna Prasadan
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Xiangwei Xiao
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - George K Gittes
- Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
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11
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Abstract
Reduction of insulin/insulin-like growth factor 1 (IGF1) signaling (IIS) extends the lifespan of various species. So far, several longevity mouse models have been developed containing mutations related to growth signaling deficiency by targeting growth hormone (GH), IGF1, IGF1 receptor, insulin receptor, and insulin receptor substrate. In addition, p70 ribosomal protein S6 kinase 1 (S6K1) knockout leads to lifespan extension. S6K1 encodes an important kinase in the regulation of cell growth. S6K1 is regulated by mechanistic target of rapamycin (mTOR) complex 1. The v-myc myelocytomatosis viral oncogene homolog (MYC)-deficient mice also exhibits a longevity phenotype. The gene expression profiles of these mice models have been measured to identify their longevity mechanisms. Here, we summarize our knowledge of long-lived mouse models related to growth and discuss phenotypic characteristics, including organ-specific gene expression patterns.
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Affiliation(s)
- Seung-Soo Kim
- Institute of Animal Molecular Biotechnology, Korea University, Seoul 02841, Korea
| | - Cheol-Koo Lee
- Institute of Animal Molecular Biotechnology, Korea University, Seoul 02841; Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 02481, Korea
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Subramanian M, Thotakura B, Chandra Sekaran SP, Jyothi AK, Sundaramurthi I. Naringin (4',5,7-Trihydroxyflavanone 7-Rhamnoglucoside) Attenuates β-Cell Dysfunction in Diabetic Rats through Upregulation of PDX-1. Cells Tissues Organs 2018; 206:133-143. [PMID: 30884485 DOI: 10.1159/000496506] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 12/28/2018] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Pancreatic duodenal homeobox-1 (PDX-1) is a key transcription factor which regulates Insulin gene expression and insulin secretion in adult β-cells and helps to maintain β-cells mass. Naringin, a flavanone, owing to its anti-oxidant property, is reported to have antidiabetic effects. OBJECTIVES The present study tries to evaluate the role of naringin on the β-cell-specific transcription factor PDX-1 in diabetic rats. METHODS Diabetes was induced in male rats using streptozotocin and treated with naringin (100 mg/kg) orally for 4 and 8 weeks. Serum insulin level, Pdx-1 and Insulin gene expression, and PDX-1 protein expression were assessed in the rat pancreas. Histopathological and ultrastructural changes in the islet and β-cells were observed. RESULTS Naringin prevented leukocytic infiltration in the pancreas of diabetic rats and recouped the β-cells with adequate secretory granules. Naringin-treated diabetic rats showed significantly increased mRNA expression of Pdx-1 and Insulin genes, increased expression of transcription factor PDX-1, and higher serum insulin levels than the diabetic control animals. These changes were more pronounced in the 8-week naringin-treated diabetic animals. CONCLUSIONS Naringin was found to be an effective antidiabetic agent which increased Insulin gene expression and insulin secretion by upregulating the PDX-1 gene and protein expression.
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Affiliation(s)
- Manickam Subramanian
- Department of Anatomy, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Chennai, India,
| | - Balaji Thotakura
- Department of Anatomy, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Chennai, India
| | | | - Ashok Kumar Jyothi
- Department of Anatomy, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Chennai, India
| | - Indumathi Sundaramurthi
- Department of Anatomy, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Chennai, India
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13
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Affiliation(s)
- Aaron R Cox
- McNair Medical Institute and Pediatric Diabetes and Endocrinology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX
| | - Jake A Kushner
- McNair Medical Institute and Pediatric Diabetes and Endocrinology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX
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14
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Bai C, Gao Y, Zhang X, Yang W, Guan W. MicroRNA-34c acts as a bidirectional switch in the maturation of insulin-producing cells derived from mesenchymal stem cells. Oncotarget 2017; 8:106844-106857. [PMID: 29290993 PMCID: PMC5739778 DOI: 10.18632/oncotarget.21883] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/21/2017] [Indexed: 01/08/2023] Open
Abstract
miRNAs regulate insulin secretion, pancreatic development, and beta-cell differentiation. However, their function in the differentiation of IPCs from MSCs is poorly understood. In this study, to screen for miRNAs and their targets that function during the formation of IPCs from MSCs, we examined the miRNA expression profiles of MSCs and IPCs using RNA-seq and qPCR to confirm the above results. We found that miR-34c exhibited transient upregulation at an early stage of the formation of IPCs derived from MSCs. Next, we analyzed the biological function of miR-34c by predicting its targets using bioinformatic tools. Combining our data with those from previous reports, we found that miR-34c and its targets play an important role in the formation of IPCs. Therefore, we overexpressed miR-34c and expressed small interfering RNAs of its targets in MSCs to investigate their functions in IPC formation. We found that miR-34c acts as a bidirectional switch in the formation of IPCs derived from MSCs by regulating the expression of targets to affect insulin synthesis and secretion. miR-34c was shown to downregulate its targets, including PDE7B, PDGFRA, and MAP2K1, to increase proinsulin synthesis, but when miR-34c continually dysregulated such expression, it suppressed the expression of other targets, namely ACSL4 and SAR1A, weakening insulin secretion in IPCs. These results suggest that endogenous miRNAs involved in the formation of IPCs from stem cells should be considered in the development of effective cell transplant therapy for diabetes.
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Affiliation(s)
- Chunyu Bai
- Key Laboratory of Precision Oncology of Shandong Higher Education, Institute of Precision Medicine, Jining Medical University, Jining, 272067, PR China.,Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Yuhua Gao
- College of Basic Medicine, Jining Medical University, Jining, 272067, PR China.,Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Xiangyang Zhang
- College of Basic Medicine, Jining Medical University, Jining, 272067, PR China
| | - Wancai Yang
- Key Laboratory of Precision Oncology of Shandong Higher Education, Institute of Precision Medicine, Jining Medical University, Jining, 272067, PR China.,Department of Pathology, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Weijun Guan
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
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Self-Transducible Bimodal PDX1-FOXP3 Protein Lifts Insulin Secretion and Curbs Autoimmunity, Boosting Tregs in Type 1 Diabetic Mice. Mol Ther 2017; 26:184-198. [PMID: 28988715 DOI: 10.1016/j.ymthe.2017.08.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 08/09/2017] [Accepted: 08/16/2017] [Indexed: 12/15/2022] Open
Abstract
Type 1 diabetes (T1D) is characterized by massive destruction of insulin-producing β cells by autoreactive T lymphocytes, arising via defective immune tolerance. Therefore, effective anti-T1D therapeutics should combine autoimmunity-preventing and insulin production-restoring properties. We constructed a cell-permeable PDX1-FOXP3-TAT fusion protein (FP) composed of two transcription factors: forkhead box P3 (FOXP3), the master regulator of differentiation and functioning of self-tolerance-promoting Tregs, and pancreatic duodenal homeobox-1 (PDX1), the crucial factor supporting β cell development and maintenance. The FP was tested in vitro and in a non-obese diabetic mouse T1D model. In vitro, FP converted naive CD4+ T cells into a functional "Treg-like" subset, which suppressed cytokine secretion, downregulated antigen-specific responses, and curbed viability of diabetogenic effector cells. In hepatic stem-like cells, FP potentiated endocrine transdifferentiation, inducing expression of Insulin2 and other β lineage-specific genes. In vivo, FP administration to chronically diabetic mice triggered (1) a significant elevation of insulin and C-peptide levels, (2) the formation of insulin-containing cell clusters in livers, and (3) a systemic anti-inflammatory shift (higher Foxp3+CD4+CD25+ T cell frequencies, elevated rates of IL-10-producing cells, and reduced rates of IFN-γ-secreting cells). Overall, in accordance with its design, PDX1-FOXP3-TAT FP delivered both Treg-stabilizing anti-autoimmune and de novo insulin-producing effects, proving its anti-T1D therapeutic potential.
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16
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Teucrium polium extract reverses symptoms of streptozotocin-induced diabetes in rats via rebalancing the Pdx1 and FoxO1 expressions. Biomed Pharmacother 2017; 93:1033-1039. [PMID: 28738518 DOI: 10.1016/j.biopha.2017.06.082] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 05/30/2017] [Accepted: 06/20/2017] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND AND OBJECTIVE Teucrium polium Lamiaceae. an antidiabetic traditional medicine was observed to stimulate insulin secretion and β-cell mass restoration in pancreatic of diabetic rats. Bioactive compounds in T. polium such as terpenoids and flavonoids have a wide range of antioxidant properties. Given this background, our research was aimed at probing the effective molecular mechanism of T. polium which in turn protects the pancreatic β-cells of diabetic rats through attenuation of streptozotocin-induced oxidative stress. MATERIALS AND METHODS Induction of diabetes by streptozotocin (STZ) injection followed by treatment of the rats with T. polium extract (0.5g/kg) and glibenclamide as a standard drug (600μg/kg) for six consecutive weeks. Besides, biochemical indexes including sera glucose and lipids were investigated once every two weeks. Moreover, oxidative stress markers were also measured in the sixth week of treatment to assess the antioxidant capacity of T. polium. Prior to sacrifice of rats, the oral glucose tolerance test was carried out and thereafter western blot analysis was performed on pancreatic tissues to detect the expression of JNK, FoxO1 and Pdx1 proteins in the experimental groups. RESULTS Oral administration of T. polium extract not only disclosed the significant anti-hyperglycemic potential of the plant, but also relieved dyslipidemia and oxidative stress related to diabetes. Furthermore, remarkable improvement of glucose tolerance was exhibited among the treated groups, confirming the presence of insulin in the blood. Subsequently, the effective molecular mechanism of T. polium was partially revealed by western blot analyses which detected considerable up-regulation of p-FoxO1 and Pdx1 proteins parallel to reduction of p-JNK expression among the treated diabetic rats. CONCLUSION This study demonstrates that T. polium extract is able to restore the β-cell mass and insulin secretion by regulation of pivotal transcription factor of the pancreatic β-cells Pdx1 in JNK pathway.
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Hani H, Allaudin ZN, Mohd-Lila MA, Sarsaifi K, Rasouli M, Tam YJ, Tengku-Ibrahim TA, Othman AM. Improvement of isolated caprine islet survival and functionality in vitro by enhancing of PDX1 gene expression. Xenotransplantation 2017; 24. [PMID: 28397308 DOI: 10.1111/xen.12302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 02/03/2017] [Accepted: 03/09/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Dead islets replaced with viable islets are a promising offer to restore normal insulin production to a person with diabetes. The main reason for establishing a new islet source for transplantation is the insufficiency of human donor pancreas while using xenogeneic islets perhaps assists this problem. The expression of PDX1 is essential for the pancreas expansion. In mature β-cells, PDX1 has several critical roles such as glucose sensing, insulin synthesis, and insulin secretion. In this study, we aimed to evaluate the expression of pancreatic duodenal homeobox-1 (PDX1) in treated caprine islets in culture and to assess the protective effects of antioxidant factors on the PDX1 gene in cultured caprine islets. MATERIALS AND METHODS Purified islets were treated with serum-free, serum, IBMX, tocopherol, or IBMX and tocopherol media. Quantitative polymerase chain reaction and Western blotting were carried out to compare the expression levels of PDX1 in treated purified islets cultured with different media. RESULTS Islets treated with IBMX/tocopherol exhibited the highest fold change in the relative expression of PDX1 on day 5 post-treatment (relative expression: 6.80±2.08), whereas serum-treated islets showed the lowest fold changes in PDX1 expression on day 5 post-treatment (0.67±0.36), as compared with the expression on day 1 post-treatment. Insulin production and viability tests of purified islets showed superiority of islet at supplemented serum-free media with IBMX/tocopherol compared to other cultures (53.875%±1.59%). CONCLUSIONS Our results indicated that supplemented serum-free medium with tocopherol and IBMX enhances viability and PDX1 gene expression compared to serum-added and serum-free media.
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Affiliation(s)
- Homayoun Hani
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Zeenathul Nazariah Allaudin
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Mohd-Azmi Mohd-Lila
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Kazhal Sarsaifi
- Department of Veterinary Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Mina Rasouli
- Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Yew Joon Tam
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Tengku-Azmi Tengku-Ibrahim
- Department of Veterinary Preclinical, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Abas Mazni Othman
- Department of Animal Reproduction, Agro-Biotechnology Institute Malaysia, Serdang, Selangor, Malaysia
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18
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Bai C, Gao Y, Li X, Wang K, Xiong H, Shan Z, Zhang P, Wang W, Guan W, Ma Y. MicroRNAs can effectively induce formation of insulin-producing cells from mesenchymal stem cells. J Tissue Eng Regen Med 2017; 11:3457-3468. [DOI: 10.1002/term.2259] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 03/28/2016] [Accepted: 07/03/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Chunyu Bai
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Yuhua Gao
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Xiangchen Li
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Kunfu Wang
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Hui Xiong
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Zhiqiang Shan
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Ping Zhang
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Wenjie Wang
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Weijun Guan
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
| | - Yuehui Ma
- Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
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Chang H, Wang D, Xia W, Pan X, Huo W, Xu S, Li Y. Epigenetic disruption and glucose homeostasis changes following low-dose maternal bisphenol A exposure. Toxicol Res (Camb) 2016; 5:1400-1409. [PMID: 30090444 PMCID: PMC6061978 DOI: 10.1039/c6tx00047a] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 06/19/2016] [Indexed: 12/19/2022] Open
Abstract
Developmental exposure to bisphenol A (BPA) has been linked to impaired glucose homeostasis and pancreatic function in adulthood, which has been hypothesized to result from the disruption of pancreatic β-cell development at early life. Here we evaluated whether maternal BPA exposure disrupts β-cell development and glucose tolerance and the role of epigenetic modifications of key regulator in this process. We found that maternal exposure to BPA (10 μg kg-1 d-1) reduced the pancreatic β-cell mass and the expression of pancreatic and duodenal homeobox 1 (Pdx1) at birth, as well as the expression of Pdx1 at gestational day (GD) 15.5. In parallel with the decreased expression of Pdx1, histones H3 and H4 deacetylation, along with demethylation of histone 3 lysine 4 (H3K4) and methylation of histone 3 lysine 9 (H3K9), were found at the promoter of Pdx1, while no significant changes in DNA methylation status were detected at this region. Moreover, these alterations were observed in adult life along with impaired glucose tolerance. We conclude that maternal exposure to BPA reduces pancreatic β-cell mass at birth by reducing PDX1+ progenitors during fetal development through altering the histone modifications of Pdx1, which can be propagated to later life and increase the susceptibility to glucose intolerance.
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Affiliation(s)
- Huailong Chang
- Key Laboratory of Environment and Health , Ministry of Education & Ministry of Environmental Protection , and State Key Laboratory of Environmental Health (incubating) , School of Public Health , Tongji Medical College , Huazhong University of Science and Technology , Wuhan 430030 , China . ; ; ; Tel: +86-27-83693417, 86-27-83657705
| | - Danqi Wang
- School of Public Health , Changsha Medical University , Changsha 410219 , China
| | - Wei Xia
- Key Laboratory of Environment and Health , Ministry of Education & Ministry of Environmental Protection , and State Key Laboratory of Environmental Health (incubating) , School of Public Health , Tongji Medical College , Huazhong University of Science and Technology , Wuhan 430030 , China . ; ; ; Tel: +86-27-83693417, 86-27-83657705
| | - Xinyun Pan
- Key Laboratory of Environment and Health , Ministry of Education & Ministry of Environmental Protection , and State Key Laboratory of Environmental Health (incubating) , School of Public Health , Tongji Medical College , Huazhong University of Science and Technology , Wuhan 430030 , China . ; ; ; Tel: +86-27-83693417, 86-27-83657705
| | - Wenqian Huo
- Key Laboratory of Environment and Health , Ministry of Education & Ministry of Environmental Protection , and State Key Laboratory of Environmental Health (incubating) , School of Public Health , Tongji Medical College , Huazhong University of Science and Technology , Wuhan 430030 , China . ; ; ; Tel: +86-27-83693417, 86-27-83657705
| | - Shunqing Xu
- Key Laboratory of Environment and Health , Ministry of Education & Ministry of Environmental Protection , and State Key Laboratory of Environmental Health (incubating) , School of Public Health , Tongji Medical College , Huazhong University of Science and Technology , Wuhan 430030 , China . ; ; ; Tel: +86-27-83693417, 86-27-83657705
| | - Yuanyuan Li
- Key Laboratory of Environment and Health , Ministry of Education & Ministry of Environmental Protection , and State Key Laboratory of Environmental Health (incubating) , School of Public Health , Tongji Medical College , Huazhong University of Science and Technology , Wuhan 430030 , China . ; ; ; Tel: +86-27-83693417, 86-27-83657705
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Ardestani A, Maedler K. MST1: a promising therapeutic target to restore functional beta cell mass in diabetes. Diabetologia 2016; 59:1843-9. [PMID: 27053234 DOI: 10.1007/s00125-016-3892-9] [Citation(s) in RCA: 40] [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: 11/16/2015] [Accepted: 12/23/2015] [Indexed: 12/31/2022]
Abstract
The loss of insulin-producing beta cells by apoptosis is a hallmark of all forms of diabetes mellitus. Strategies to prevent beta cell apoptosis and dysfunction are urgently needed to restore the insulin-producing cells and to prevent severe diabetes progression. We recently identified the serine/threonine kinase known as mammalian sterile 20-like kinase 1 (MST1) as a critical regulator of apoptotic beta cell death and dysfunction. MST1 activates several apoptotic signalling pathways, which further stimulate its own cleavage, leading to a vicious cycle of cell death. This led us to hypothesise that MST1 signalling is central to the initiation of beta cell death in diabetes. We found that MST1 is strongly activated in a diabetic beta cell and induces not only its death but also directly impairs insulin secretion through promoting proteasomal degradation of key beta cell transcription factor, pancreatic and duodenal homeobox 1 (PDX1), which is critical for insulin production.Pre-clinical studies in various animal models of diabetes have reported that MST1 deficiency remarkably restores normoglycaemia and beta cell function and prevents the development of diabetes. Importantly, MST1 deficiency can revert fully diabetic beta cells to a non-diabetic state. MST1 may serve as a target for the development of novel therapies for diabetes that trigger the cause of the disease, namely, the destruction of the beta cells. The major current focus of our investigation is to identify and test the efficacy of potent inhibitors of this death signalling pathway to protect beta cells against the effects of autoimmune attack in type 1 diabetes and to preserve beta cell mass and function in type 2 diabetes. This review summarises a presentation given at the 'Can we make a better beta cell?' symposium at the 2015 annual meeting of the EASD. It is accompanied by two other reviews on topics from this symposium (by Heiko Lickert and colleagues, DOI: 10.1007/s00125-016-3949-9 , and by Harry Heimberg and colleagues, DOI: 10.1007/s00125-016-3879-6 ) and a commentary by the Session Chair, Shanta Persaud (DOI: 10.1007/s00125-016-3870-2 ).
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Affiliation(s)
- Amin Ardestani
- Islet Biology Laboratory, Centre for Biomolecular Interactions Bremen, University of Bremen, Leobener Straße NW2, Room B2080, 28359, Bremen, Germany.
| | - Kathrin Maedler
- Islet Biology Laboratory, Centre for Biomolecular Interactions Bremen, University of Bremen, Leobener Straße NW2, Room B2080, 28359, Bremen, Germany.
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Bai C, Li X, Gao Y, Yuan Z, Hu P, Wang H, Liu C, Guan W, Ma Y. Melatonin improves reprogramming efficiency and proliferation of bovine-induced pluripotent stem cells. J Pineal Res 2016; 61:154-67. [PMID: 27090494 DOI: 10.1111/jpi.12334] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 04/12/2016] [Indexed: 12/18/2022]
Abstract
Melatonin can modulate neural stem cell (NSC) functions such as proliferation and differentiation into NSC-derived pluripotent stem cells (N-iPS) in brain tissue, but the effect and mechanism underlying this are unclear. Thus, we studied how primary cultured bovine NSCs isolated from the retinal neural layer could transform into N-iPS cell. NSCs were exposed to 0.01, 0.1, 1, 10, or 100 μm melatonin, and cell viability studies indicated that 10 μm melatonin can significantly increase cell viability and promote cell proliferation in NSCs in vitro. Thus, 10 μm melatonin was used to study miR-302/367-mediated cell reprogramming of NSCs. We noted that this concentration of melatonin increased reprogramming efficiency of N-iPS cell generation from primary cultured bovine NSCs and that this was mediated by downregulation of apoptosis-related genes p53 and p21. Then, N-iPS cells were treated with 1, 10, 100, or 500 μm melatonin, and N-iPS (M-N-iPS) cell proliferation was measured. We noted that 100 μm melatonin increased proliferation of N-iPS cells via increased phosphorylation of intracellular ERK1/2 via activation of its pathway in M-N-iPS via melatonin receptors 1 (MT1). Finally, we verified that N-iPS cells and M-N-iPS cells are similar to typical embryonic stem cells including the expression of pluripotency markers (Oct4 and Nanog), the ability to form teratomas in vivo, and the capacity to differentiate into all three embryonic germ layers.
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Affiliation(s)
- Chunyu Bai
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiangchen Li
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuhua Gao
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- College of Wildlife Resources, Northeast Forestry University, Harbin, China
| | - Ziao Yuan
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- College of Wildlife Resources, Northeast Forestry University, Harbin, China
| | - Pengfei Hu
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Hui Wang
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Department of Food Science and Engineering, Liaoning Medical University, Jinzhou, China
| | - Changqing Liu
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Department of Bioscience, Bengbu Medical College, Bengbu, China
| | - Weijun Guan
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuehui Ma
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
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22
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Yang P, Pei Q, Yu T, Chang Q, Wang D, Gao M, Zhang X, Liu Y. Compromised Wound Healing in Ischemic Type 2 Diabetic Rats. PLoS One 2016; 11:e0152068. [PMID: 27028201 PMCID: PMC4814123 DOI: 10.1371/journal.pone.0152068] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 03/07/2016] [Indexed: 02/06/2023] Open
Abstract
Ischemia is one of the main epidemic factors and characteristics of diabetic chronic wounds, and exerts a profound effect on wound healing. To explore the mechanism of and the cure for diabetic impaired wound healing, we established a type 2 diabetic rat model. We used an 8weeks high fat diet (HFD) feeding regimen followed by multiple injections of streptozotocin (STZ) at a dose of 10mg/kg to induce Wister rat to develop type 2 diabetes. Metabolic characteristics were assessed at the 5th week after the STZ injections to confirm the establishment of diabetes mellitus on the rodent model. A bipedicle flap, with length to width ratio 1.5, was performed on the back of the rat to make the flap area ischemic. Closure of excisional wounds on this bipedicle flap and related physiological and pathological changes were studied using histological, immunohistochemical, real time PCR and protein immunoblot approaches. Our results demonstrated that a combination of HFD feeding and a low dose of STZ is capable of inducing the rats to develop type 2 diabetes with noticeable insulin resistance, persistent hyperglycemia, moderate degree of insulinemia, as well as high serum cholesterol and high triglyceride levels. The excision wounds on the ischemic double pedicle flap showed deteriorative healing features comparing with non-ischemic diabetic wounds, including: delayed healing, exorbitant wound inflammatory response, excessive and prolonged ROS production and excessive production of MMPs. Our study suggested that HFD feeding combined with STZ injection could induce type 2 diabetes in rat. Our ischemic diabetic wound model is suitable for the investigation of human diabetic related wound repair; especically for diabetic chronic wounds.
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Affiliation(s)
- Peilang Yang
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
| | - Qing Pei
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
| | - Tianyi Yu
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
| | - Qingxuan Chang
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
| | - Di Wang
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
| | - Min Gao
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
| | - Xiong Zhang
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
| | - Yan Liu
- Department of Burn and Plastic Surgery, Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
- * E-mail:
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Role of microRNA-21 in the formation of insulin-producing cells from pancreatic progenitor cells. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1859:280-93. [DOI: 10.1016/j.bbagrm.2015.12.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 11/17/2015] [Accepted: 12/02/2015] [Indexed: 12/20/2022]
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Ma CT, Wu YJ, Huang HH, Kang PL, Hsiao KY, Lo DY, Kuo SM. In vitro and in vivo evaluation of the effect of nano-sized collagen molecules and nicotinamide on mesenchymal stem cell differentiation. J Mater Chem B 2016; 4:3892-3902. [DOI: 10.1039/c6tb00731g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Advances and improvements in mesenchymal stromal/stem cells (MSCs) and cell replacement therapies have been promising approaches to treat diabetes mellitus (DM) since their potent capacities for differentiation into various functional cells match the demands of tissue repair and regeneration.
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Affiliation(s)
- Chin-Tsu Ma
- Department of Biomedical Engineering
- I-Shou University
- Kaohsiung City 82445
- Taiwan
| | - Yi-Jhen Wu
- Department of Biomedical Engineering
- I-Shou University
- Kaohsiung City 82445
- Taiwan
| | - Han Hsiang Huang
- Department of Veterinary Medicine
- National Chiayi University
- Chiayi City
- Taiwan
| | - Pei-Leun Kang
- Cardiac Surgery
- Kaohsiung Veterans General Hospital
- Kaohsiung City
- Taiwan
| | - Kuan Yin Hsiao
- Department of Biomedical Engineering
- I-Shou University
- Kaohsiung City 82445
- Taiwan
| | - Dan Yuan Lo
- Department of Veterinary Medicine
- National Chiayi University
- Chiayi City
- Taiwan
| | - Shyh Ming Kuo
- Department of Biomedical Engineering
- I-Shou University
- Kaohsiung City 82445
- Taiwan
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The Soybean Peptide Vglycin Preserves the Diabetic β-cells through Improvement of Proliferation and Inhibition of Apoptosis. Sci Rep 2015; 5:15599. [PMID: 26510947 PMCID: PMC4625148 DOI: 10.1038/srep15599] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 09/29/2015] [Indexed: 01/18/2023] Open
Abstract
Replenishment of insulin-producing pancreatic β-cells would be beneficial in diabetes. The number of β-cells is maintained primarily by self-neogenesis to compensate for β-cell failure, loss or dedifferentiation. We present here a polypeptide vglycin, which was isolated and purified from germinating pea seeds. Vglycin exhibited positive effects in our diabetic models by promoting the proliferation and suppressing the apoptosis and dedifferentiation of β-cells. Vglycin promoted the restoration of β-cells in both young streptozotocin (STZ)-induced type 1 diabetic SD rats and in aged high-fat diet with (or without) STZ-induced type 2 diabetic C57BL/6 mice. We demonstrated that vglycin triggers this positive signaling by activating the insulin receptor and corresponding transcription factors. Impaired insulin sensitivity and glucose tolerance in aged T2DM mice were dramatically improved after long-term vglycin treatment, consistent with the altered level of inflammatory factor IL-1β/6. In addition, energy expenditure and body weights were significantly decreased in the mouse models after vglycin therapy. These results provide insight into the protective effects of vglycin on ameliorating β-cell function in standing glucolipotoxicity. Thus, vglycin may represent a new therapeutic agent for preventing and treating diabetes by replenishing endogenous insulin-positive cells.
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Muller YL, Hanson RL, Wiessner G, Nieboer L, Kobes S, Piaggi P, Abdussamad M, Okani C, Knowler WC, Bogardus C, Baier LJ. Assessing FOXO1A as a potential susceptibility locus for type 2 diabetes and obesity in American Indians. Obesity (Silver Spring) 2015; 23:1960-5. [PMID: 26337673 PMCID: PMC4586407 DOI: 10.1002/oby.21236] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 07/03/2015] [Indexed: 01/17/2023]
Abstract
OBJECTIVE A prior genome-wide association study (GWAS) in Pima Indians identified variation within FOXO1A that modestly associated with early-onset (onset age < 25 years) type 2 diabetes (T2D). FOXO1A encodes the forkhead transcription factor involved in pancreatic β-cell growth and hypothalamic energy balance; therefore, FOXO1A was analyzed as a candidate gene for T2D and obesity in a population-based sample of 7,710 American Indians. METHODS Tag SNPs in/near FOXO1A (minor allele frequency ≥ 0.05) were analyzed for association with T2D at early onset (n = 1,060) and all ages (n = 7,710) and with insulin secretion (n = 298). SNPs were also analyzed for association with maximum body mass index (BMI) in adulthood (n = 5,918), maximum BMI z-score in childhood (n = 5,350), and % body fat (n = 555). RESULTS An intronic SNP rs2297627 associated with early-onset T2D [OR = 1.34 (1.13-1.58), P = 8.7 × 10(-4)] and T2D onset at any age [OR = 1.19 (1.09-1.30), P = 1 × 10(-4) ]. The T2D risk allele also associated with lower acute insulin secretion (β = 0.88, as a multiplier, P = 0.02). Another intronic SNP (rs1334241, D' = 0.99, r(2) = 0.49 with rs2297627) associated with maximum adulthood BMI (β = 1.02, as a multiplier, P = 3 × 10(-5)), maximum childhood BMI z-score (β = 0.08, P = 3 × 10(-4)), and % body fat (β = 0.83%, P = 0.04). CONCLUSIONS Common variation in FOXO1A may modestly affect risk for T2D and obesity in American Indians.
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Affiliation(s)
- Yunhua L Muller
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Robert L Hanson
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Gregory Wiessner
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Lori Nieboer
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Sayuko Kobes
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Paolo Piaggi
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Mahdi Abdussamad
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Chidinma Okani
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - William C Knowler
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Clifton Bogardus
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
| | - Leslie J Baier
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes Of Health, Phoenix, Arizona, USA
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Alvarez-Perez JC, Rosa TC, Casinelli GP, Valle SR, Lakshmipathi J, Rosselot C, Rausell-Palamos F, Vasavada RC, García-Ocaña A. Hepatocyte growth factor ameliorates hyperglycemia and corrects β-cell mass in IRS2-deficient mice. Mol Endocrinol 2015; 28:2038-48. [PMID: 25361392 DOI: 10.1210/me.2014-1207] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Insulin resistance, when combined with decreased β-cell mass and relative insufficient insulin secretion, leads to type 2 diabetes. Mice lacking the IRS2 gene (IRS2(-/-) mice) develop diabetes due to uncompensated insulin resistance and β-cell failure. Hepatocyte growth factor (HGF) activates the phosphatidylinositol 3-kinase/Akt signaling pathway in β-cells without recruitment of IRS1 or IRS2 and increases β-cell proliferation, survival, mass, and function when overexpressed in β-cells of transgenic (TG) mice. We therefore hypothesized that HGF may protect against β-cell failure in IRS2 deficiency. For that purpose, we cross-bred TG mice overexpressing HGF in β-cells with IRS2 knockout (KO) mice. Glucose homeostasis analysis revealed significantly reduced hyperglycemia, compensatory hyperinsulinemia, and improved glucose tolerance in TG/KO mice compared with those in KO mice in the context of similar insulin resistance. HGF overexpression also increased glucose-stimulated insulin secretion in IRS2(-/-) islets. To determine whether this glucose homeostasis improvement correlated with alterations in β-cells, we measured β-cell mass, proliferation, and death in these mice. β-Cell proliferation was increased and death was decreased in TG/KO mice compared with those in KO mice. As a result, β-cell mass was significantly increased in TG/KO mice compared with that in KO mice, reaching levels similar to those in wild-type mice. Analysis of the intracellular targets involved in β-cell failure in IRS2 deficiency showed Pdx-1 up-regulation, Akt/FoxO1 phosphorylation, and p27 down-regulation in TG/KO mouse islets. Taken together, these results indicate that HGF can compensate for IRS2 deficiency and subsequent insulin resistance by normalizing β-cell mass and increasing circulating insulin. HGF may be of value as a therapeutic agent against β-cell failure.
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Affiliation(s)
- Juan C Alvarez-Perez
- Diabetes, Obesity and Metabolism Institute (J.C.A.-P., J.L., C.R., F.R.-P., R.C.V., A.G.-O.), Division of Endocrinology, Diabetes and Bone Diseases, The Mindich Child Health and Development Institute, Icahn School of Medicine at Mt Sinai, New York, New York 10029; and Department of Medicine (T.C.R., G.P.C., S.R.V.), Division of Endocrinology and Metabolism, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
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Hughey CC, Wasserman DH, Lee-Young RS, Lantier L. Approach to assessing determinants of glucose homeostasis in the conscious mouse. Mamm Genome 2014; 25:522-38. [PMID: 25074441 DOI: 10.1007/s00335-014-9533-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 07/04/2014] [Indexed: 01/11/2023]
Abstract
Obesity and type 2 diabetes lessen the quality of life of those afflicted and place considerable burden on the healthcare system. Furthermore, the detrimental impact of these pathologies is expected to persist or even worsen. Diabetes is characterized by impaired insulin action and glucose homeostasis. This has led to a rapid increase in the number of mouse models of metabolic disease being used in the basic sciences to assist in facilitating a greater understanding of the metabolic dysregulation associated with obesity and diabetes, the identification of therapeutic targets, and the discovery of effective treatments. This review briefly describes the most frequently utilized models of metabolic disease. A presentation of standard methods and technologies on the horizon for assessing metabolic phenotypes in mice, with particular emphasis on glucose handling and energy balance, is provided. The article also addresses issues related to study design, selection and execution of metabolic tests of glucose metabolism, the presentation of data, and interpretation of results.
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Affiliation(s)
- Curtis C Hughey
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University, 823 Light Hall, 2215 Garland Ave, Nashville, TN, 37232, USA,
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29
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Liu Y, Jiang X, Zeng Y, Zhou H, Yang J, Cao R. Proliferating pancreatic beta-cells upregulate ALDH. Histochem Cell Biol 2014; 142:685-91. [PMID: 25028343 DOI: 10.1007/s00418-014-1248-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2014] [Indexed: 12/15/2022]
Abstract
High levels of aldehyde dehydrogenase (ALDH) activity have been regarded as a specific feature of progenitor cells and stem cells. Hence, as an indicator of ALDH activity, aldefluor fluorescence has been widely used for the identification and isolation of stem and progenitor cells. ALDH activity was recently detected in embryonic mouse pancreas, and specifically and exclusively in adult centroacinar and terminal duct cells, suggesting that these duct cells may harbor cells of endocrine and exocrine differentiation potential in the adult pancreas. Here, we report the presence of aldefluor+ beta-cells in a beta-cell proliferation model, partial pancreatectomy. The aldefluor+ beta-cells are essentially all positive for Ki-67 and expressed high levels of cell-cycle activators such as CyclinD1, CyclinD2, and CDK4, suggesting that they are mitotic cells. Our data thus reveal a potential change in ALDH activity of proliferating beta-cells, which provides a novel method for the isolation and analysis of proliferating beta-cells. Moreover, our data also suggest that aldefluor lineage-tracing is not a proper method for analyzing progenitor or stem activity in the adult pancreas.
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Affiliation(s)
- Yinglan Liu
- Department of Endocrinology, The First Affiliated Hospital of Nanhua University, No. 69 Chuanshan Road, Hengyang, 421001, Hunan Province, China
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Mangiferin facilitates islet regeneration and β-cell proliferation through upregulation of cell cycle and β-cell regeneration regulators. Int J Mol Sci 2014; 15:9016-35. [PMID: 24853132 PMCID: PMC4057772 DOI: 10.3390/ijms15059016] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 04/21/2014] [Accepted: 04/24/2014] [Indexed: 11/17/2022] Open
Abstract
Mangiferin, a xanthonoid found in plants including mangoes and iris unguicularis, was suggested in previous studies to have anti-hyperglycemic function, though the underlying mechanisms are largely unknown. This study was designed to determine the therapeutic effect of mangiferin by the regeneration of β-cells in mice following 70% partial pancreatectomy (PPx), and to explore the mechanisms of mangiferin-induced β-cell proliferation. For this purpose, adult C57BL/6J mice after 7–14 days post-PPx, or a sham operation were subjected to mangiferin (30 and 90 mg/kg body weight) or control solvent injection. Mangiferin-treated mice exhibited an improved glycemia and glucose tolerance, increased serum insulin levels, enhanced β-cell hyperplasia, elevated β-cell proliferation and reduced β-cell apoptosis. Further dissection at the molecular level showed several key regulators of cell cycle, such as cyclin D1, D2 and cyclin-dependent kinase 4 (Cdk4) were significantly up-regulated in mangiferin-treated mice. In addition, critical genes related to β-cell regeneration, such as pancreatic and duodenal homeobox 1 (PDX-1), neurogenin 3 (Ngn3), glucose transporter 2 (GLUT-2), Forkhead box protein O1 (Foxo-1), and glucokinase (GCK), were found to be promoted by mangiferin at both the mRNA and protein expression level. Thus, mangiferin administration markedly facilitates β-cell proliferation and islet regeneration, likely by regulating essential genes in the cell cycle and the process of islet regeneration. These effects therefore suggest that mangiferin bears a therapeutic potential in preventing and/or treating the diabetes.
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31
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Retinal neurodegenerative changes in the adult insulin receptor substrate-2 deficient mouse. Exp Eye Res 2014; 124:1-10. [PMID: 24792588 DOI: 10.1016/j.exer.2014.04.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 04/17/2014] [Accepted: 04/22/2014] [Indexed: 11/23/2022]
Abstract
Insulin receptor substrate-2 (Irs2) mediates peripheral insulin action and is essential for retinal health. Previous investigations have reported severe photoreceptor degeneration and abnormal visual function in Irs2-deficient mice. However, molecular changes in the Irs2(-)(/)(-) mouse retina have not been described. In this study, we examined retinal degenerative changes in neuronal and glial cells of adult (9- and 12-week old) Irs2(-)(/)(-) mice by immunohistochemistry. 9-week old Irs2(-)(/)(-) mice showed significant thinning of outer retinal layers, concomitant to Müller and microglial cell activation. Photoreceptor cells displayed different signs of degeneration, such as outer/inner segment atrophy, redistribution of rod- and cone-opsins and spatial disorganization of cone cells. This was accompanied by synaptic changes at the outer plexiform layer, including the retraction of rod-spherules, reduction of photoreceptor synaptic ribbons and synaptic remodeling in second order neurons (i.e. loss and sprouting of dendritic processes in rod bipolar and horizontal cells). By 12 weeks of age, the thickness of inner retinal layers was severely affected. Although inner plexiform layer stratification remained unchanged at this stage, rod bipolar cell axon terminals were significantly depleted. Significant loss of Brn3a(+) retinal ganglion cells occurred in 12-week old Irs2(-)(/)(-) mice, in contrast to younger ages. Adult Irs2(-)(/)(-) mice showed clear hallmarks of neurodegeneration and disruption of the inner retina with increasing age. Pharmacological stimulation of Irs2 signaling pathway may provide additional neuroprotection in certain degenerative retinopathies.
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32
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Zhang X, Han W, Jiang X, Li M, Gao L, Zhao JJ. Chronic leucine exposure results in reduced but reversible glucose-stimulated insulin secretion in INS-1 cells. Mol Med Rep 2014; 9:2554-8. [PMID: 24715028 DOI: 10.3892/mmr.2014.2122] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 03/03/2014] [Indexed: 11/05/2022] Open
Abstract
Previous studies have demonstrated that sustained high leucine exposure decreases glucose-stimulated insulin secretion (GSIS). However, whether this effect is recoverable following the removal of leucine is unclear. Pancreatic/duodenal homeobox-1 (PDX-1) and its downstream target, glucose transporter 2 (GLUT2), are reported to be positively associated with insulin secretion. However, it also remains unclear whether the effect of leucine on GSIS is accompanied by alterations in PDX-1 and GLUT2. In the present study, insulin secretion, insulin content, PDX-1 and GLUT2 protein expression in INS-1 (rat insulinoma cell line) cells were assessed following a 24-h incubation in 40 mmol/l leucine. Half of the cells were incubated in leucine-free media for a further 24 h to observe the abovementioned effects. In contrast to the control, 40 mmol/l leucine for 24 or 48 h diminished GSIS at high glucose concentrations by 11% (P=0.026) or 22% (P=0.003), insulin content by 14% (P=0.008) or 20% (P=0.002), as well as decreasing PDX-1 and GLUT2 expression. When leucine was removed from the media for a further 24-h incubation, in comparison with those cells that were maintained in leucine treatment for 24 and 48 h, the high GSIS increased by 13% (P=0.032) and 27% (P=0.002), insulin content was augmented by 10% (P=0.014) and 20% (P=0.003), and the protein expression of PDX-1 and GLUT2 also increased. The present study demonstrates that sustained high concentrations of leucine induce a reversible impairment of GSIS and alter insulin content, which is mediated by PDX-1 and GLUT2, in INS-1 cells.
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Affiliation(s)
- Xiujuan Zhang
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Wenxia Han
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Xiuyun Jiang
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Min Li
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Ling Gao
- The Scientific Center, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Jia Jun Zhao
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
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Chen Z, Morris DL, Jiang L, Liu Y, Rui L. SH2B1 in β-cells regulates glucose metabolism by promoting β-cell survival and islet expansion. Diabetes 2014; 63:585-95. [PMID: 24150605 PMCID: PMC3900537 DOI: 10.2337/db13-0666] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
IGF-1 and insulin promote β-cell expansion by inhibiting β-cell death and stimulating β-cell proliferation, and the phosphatidylinositol (PI) 3-kinase/Akt pathway mediates insulin and IGF-1 action. Impaired β-cell expansion is a risk factor for type 2 diabetes. Here, we identified SH2B1, which is highly expressed in β-cells, as a novel regulator of β-cell expansion. Silencing of SH2B1 in INS-1 832/13 β-cells attenuated insulin- and IGF-1-stimulated activation of the PI 3-kinase/Akt pathway and increased streptozotocin (STZ)-induced apoptosis; conversely, overexpression of SH2B1 had the opposite effects. Activation of the PI 3-kinase/Akt pathway in β-cells was impaired in pancreas-specific SH2B1 knockout (PKO) mice fed a high-fat diet (HFD). HFD-fed PKO mice also had increased β-cell apoptosis, decreased β-cell proliferation, decreased β-cell mass, decreased pancreatic insulin content, impaired insulin secretion, and exacerbated glucose intolerance. Furthermore, PKO mice were more susceptible to STZ-induced β-cell destruction, insulin deficiency, and hyperglycemia. These data indicate that SH2B1 in β-cells is an important prosurvival and proproliferative protein and promotes compensatory β-cell expansion in the insulin-resistant state and in response to β-cell stress.
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Affiliation(s)
- Zheng Chen
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - David L. Morris
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Lin Jiang
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Yong Liu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Liangyou Rui
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
- Corresponding author: Liangyou Rui,
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Role of the mammalian target of rapamycin (mTOR) complexes in pancreatic β-cell mass regulation. VITAMINS AND HORMONES 2014; 95:425-69. [PMID: 24559928 DOI: 10.1016/b978-0-12-800174-5.00017-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Exquisite regulation of insulin secretion by pancreatic β-cells is essential to maintain metabolic homeostasis. β-Cell mass must be accordingly adapted to metabolic needs and can be largely modified under different situations. The mammalian target of rapamycin (mTOR) complexes has been consistently identified as key modulators of β-cell mass. mTOR can be found into two different complexes, mTORC1 and mTORC2. Under systemic insulin resistance, mTORC1/mTORC2 signaling in β-cells is needed to increase β-cell mass and insulin secretion. However, type 2 diabetes arises when these compensatory mechanisms fail, being the role of mTOR complexes still obscure in β-cell failure. In this chapter, we introduce the protein composition and regulation of mTOR complexes and their role in pancreatic β-cells. Furthermore, we describe their main signaling effectors through the review of numerous animal models, which indicate the essential role of mTORC1/mTORC2 in pancreatic β-cell mass regulation.
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Oliveira JM, Rebuffat SA, Gasa R, Burks DJ, Garcia A, Kalko SG, Zafra D, Guinovart JJ, Gomis R. Tungstate promotes β-cell survival in Irs2-/- mice. Am J Physiol Endocrinol Metab 2014; 306:E36-47. [PMID: 24253047 DOI: 10.1152/ajpendo.00409.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Pancreatic β-cells play a central role in type 2 diabetes (T2D) development, which is characterized by the progressive decline of the functional β-cell mass that is associated mainly with increased β-cell apoptosis. Thus, understanding how to enhance survival of β-cells is key for the management of T2D. The insulin receptor substrate-2 (IRS-2) protein is pivotal in mediating the insulin/IGF signaling pathway in β-cells. In fact, IRS-2 is critically required for β-cell compensation in conditions of increased insulin demand and for β-cell survival. Tungstate is a powerful antidiabetic agent that has been shown to promote β-cell recovery in toxin-induced diabetic rodent models. In this study, we investigated whether tungstate could prevent the onset of diabetes in a scenario of dysregulated insulin/IGF signaling and massive β-cell death. To this end, we treated mice deficient in IRS2 (Irs2(-/-)), which exhibit severe β-cell loss, with tungstate for 3 wk. Tungstate normalized glucose tolerance in Irs2(-/-) mice in correlation with increased β-cell mass, increased β-cell replication, and a striking threefold reduction in β-cell apoptosis. Islets from treated Irs2(-/-) exhibited increased phosphorylated Erk1/2. Interestingly, tungstate repressed apoptosis-related genes in Irs2(-/-) islets in vitro, and ERK1/2 blockade abolished some of these effects. Gene expression profiling showed evidence of a broad impact of tungstate on cell death pathways in islets from Irs2(-/-) mice, consistent with reduced apoptotic rates. Our results support the finding that β-cell death can be arrested in the absence of IRS2 and that therapies aimed at reversing β-cell mass decline are potential strategies to prevent the progression to T2D.
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Affiliation(s)
- Joana Moitinho Oliveira
- Diabetes and Obesity Research Laboratory, Institut d'Investigations Biomediques August Pi i Sunyer, Barcelona, Spain
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Auffret J, Freemark M, Carré N, Mathieu Y, Tourrel-Cuzin C, Lombès M, Movassat J, Binart N. Defective prolactin signaling impairs pancreatic β-cell development during the perinatal period. Am J Physiol Endocrinol Metab 2013; 305:E1309-18. [PMID: 24064341 PMCID: PMC3840213 DOI: 10.1152/ajpendo.00636.2012] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Prolactin (PRL) and placental lactogens stimulate β-cell replication and insulin production in pancreatic islets and insulinoma cells through binding to the PRL receptor (PRLR). However, the contribution of PRLR signaling to β-cell ontogeny and function in perinatal life and the effects of the lactogens on adaptive islet growth are poorly understood. We provide evidence that expansion of β-cell mass during both embryogenesis and the postnatal period is impaired in the PRLR(-/-) mouse model. PRLR(-/-) newborns display a 30% reduction of β-cell mass, consistent with reduced proliferation index at E18.5. PRL stimulates leucine incorporation and S6 kinase phosphorylation in INS-1 cells, supporting a role for β-cell mTOR signaling in PRL action. Interestingly, a defect in the development of acini is also observed in absence of PRLR signaling, with a sharp decline in cellular size in both endocrine and exocrine compartments. Of note, a decrease in levels of IGF-II, a PRL target, in the Goto-Kakizaki (GK) rat, a spontaneous model of type 2 diabetes, is associated with a lack of PRL-mediated β-cell proliferation in embryonic pancreatic buds. Reduced pancreatic IGF-II expression in both rat and mouse models suggests that this factor may constitute a molecular link between PRL signaling and cell ontogenesis. Together, these results provide evidence that PRL signaling is essential for pancreas ontogenesis during the critical perinatal window responsible for establishing functional β-cell reserve.
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Zhu Y, You W, Wang H, Li Y, Qiao N, Shi Y, Zhang C, Bleich D, Han X. MicroRNA-24/MODY gene regulatory pathway mediates pancreatic β-cell dysfunction. Diabetes 2013; 62:3194-206. [PMID: 23761103 PMCID: PMC3749364 DOI: 10.2337/db13-0151] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Overnutrition and genetics both contribute separately to pancreatic β-cell dysfunction, but how these factors interact is unclear. This study was aimed at determining whether microRNAs (miRNAs) provide a link between these factors. In this study, miRNA-24 (miR-24) was highly expressed in pancreatic β-cells and further upregulated in islets from genetic fatty (db/db) or mice fed a high-fat diet, and islets subject to oxidative stress. Overexpression of miR-24 inhibited insulin secretion and β-cell proliferation, potentially involving 351 downregulated genes. By using bioinformatic analysis combined with luciferase-based promoter activity assays and quantitative real-time PCR assays, we identified two maturity-onset diabetes of the young (MODY) genes as direct targets of miR-24. Silencing either of these MODY genes (Hnf1a and Neurod1) mimicked the cellular phenotype caused by miR-24 overexpression, whereas restoring their expression rescued β-cell function. Our findings functionally link the miR-24/MODY gene regulatory pathway to the onset of type 2 diabetes and create a novel network between nutrient overload and genetic diabetes via miR-24.
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Affiliation(s)
- Yunxia Zhu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Weiyan You
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Hongdong Wang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Yating Li
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Nan Qiao
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Yuguang Shi
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Chenyu Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, People’s Republic of China
| | - David Bleich
- University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey
| | - Xiao Han
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
- Corresponding author: Xiao Han,
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Pdx-1 activates islet α- and β-cell proliferation via a mechanism regulated by transient receptor potential cation channels 3 and 6 and extracellular signal-regulated kinases 1 and 2. Mol Cell Biol 2013; 33:4017-29. [PMID: 23938296 DOI: 10.1128/mcb.00469-13] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The homeodomain transcription factor Pdx-1 has important roles in pancreatic development and β-cell function and survival. In the present study, we demonstrate that adenovirus-mediated overexpression of Pdx-1 in rat or human islets also stimulates cell replication. Moreover, cooverexpression of Pdx-1 with another homeodomain transcription factor, Nkx6.1, has an additive effect on proliferation compared to either factor alone, implying discrete activating mechanisms. Consistent with this, Nkx6.1 stimulates mainly β-cell proliferation, whereas Pdx-1 stimulates both α- and β-cell proliferation. Furthermore, cyclins D1/D2 are upregulated by Pdx-1 but not by Nkx6.1, and inhibition of cdk4 blocks Pdx-1-stimulated but not Nkx6.1-stimulated islet cell proliferation. Genes regulated by Pdx-1 but not Nkx6.1 were identified by microarray analysis. Two members of the transient receptor potential cation (TRPC) channel family, TRPC3 and TRPC6, are upregulated by Pdx-1 overexpression, and small interfering RNA (siRNA)-mediated knockdown of TRPC3/6 or TRPC6 alone inhibits Pdx-1-induced but not Nkx6.1-induced islet cell proliferation. Pdx-1 also stimulates extracellular signal-regulated kinase 1 and 2 (ERK1/2) phosphorylation, an effect partially blocked by knockdown of TRPC3/6, and blockade of ERK1/2 activation with a MEK1/2 inhibitor partially impairs Pdx-1-stimulated proliferation. These studies define a pathway by which overexpression of Pdx-1 activates islet cell proliferation that is distinct from and additive to a pathway activated by Nkx6.1.
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Nakajima K, Jain S, Ruiz de Azua I, McMillin SM, Rossi M, Wess J. Minireview: Novel aspects of M3 muscarinic receptor signaling in pancreatic β-cells. Mol Endocrinol 2013; 27:1208-16. [PMID: 23820900 DOI: 10.1210/me.2013-1084] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The release of insulin from pancreatic β-cells is regulated by a considerable number of G protein-coupled receptors. During the past several years, we have focused on the physiological importance of β-cell M3 muscarinic acetylcholine receptors (M3Rs). At the molecular level, the M3R selectively activates G proteins of the G(q) family. Phenotypic analysis of several M3R mutant mouse models, including a mouse strain that lacks M3Rs only in pancreatic β-cells, indicated that β-cell M3Rs play a key role in maintaining blood glucose levels within a normal range. Additional studies with transgenic M3R mouse models strongly suggest that strategies aimed to enhance signaling through β-cell M3Rs may prove useful in the treatment of type 2 diabetes. More recently, we analyzed transgenic mice that expressed an M3R-based designer receptor in a β-cell-specific fashion, which enabled us to chronically activate a β-cell G(q)-coupled receptor by a drug that is otherwise pharmacologically inert. Drug-dependent activation of this designer receptor stimulated the sequential activation of G(q), phospholipase C, ERK1/2, and insulin receptor substrate 2 signaling, thus triggering a series of events that greatly improved β-cell function. Most importantly, chronic stimulation of this pathway protected mice against experimentally induced diabetes and glucose intolerance, induced either by streptozotocin or by the consumption of an energy-rich, high-fat diet. Because β-cells are endowed with numerous receptors that mediate their cellular effects via activation of G(q)-type G proteins, these findings provide a rational basis for the development of novel antidiabetic drugs targeting this class of receptors.
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Affiliation(s)
- Kenichiro Nakajima
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
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Dave SD, Vanikar AV, Trivedi HL. In-vitro generation of human adipose tissue derived insulin secreting cells: up-regulation of Pax-6, Ipf-1 and Isl-1. Cytotechnology 2013; 66:299-307. [PMID: 23657630 DOI: 10.1007/s10616-013-9573-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 04/16/2013] [Indexed: 10/26/2022] Open
Abstract
We present a study of up-regulation of genes responsible for pancreatic development in glucose-sensitive insulin-secreting mesenchymal stem cells (IS-MSC) generated and differentiated from human adipose tissue (h-AD), with use of our specific differentiation media and without use of any xenogenic material. Anterior wall abdominal fat was collected from 56 volunteers and cultured in self-designed proliferation medium for 10 days. Cells were harvested by trypsinization and differentiated into insulin-expressing cells using self-designed differentiation medium for 3 days followed by evaluation for transcriptional factors Pax-6, Ipf-1, Isl-1, C-peptide and insulin secretion. Generated IS-MSC showed expression of Pax-6, Pdx-6 and Isl-1. Non-differentiated MSC as well as their further culture in absence of differentiation medium were used as negative controls. Generated 56 IS-MSC cell-lines were glucose responsive i.e. mean C-Peptide and insulin secretion levels were measured 0.41 ng/ml and 13.13 μU/ml, respectively, in absence of glucose which rose to 1.18 ng/ml and 83.42 μU/ml, respectively, following glucose challenge (p < 0.001). The mean rise in C-peptide and insulin secretion levels was 2.88 and 6.35 fold, respectively. To conclude insulin-secreting h-AD-MSC can be generated safely and effectively with application of specific differentiation media without xenogeneic material/any genetic modification, showing expression of transcriptional factors Pax-6, Ipf-1 and Isl-1.
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Affiliation(s)
- Shruti D Dave
- Stem Cell Lab, Transplantation Biology Research Centre, Department of Pathology, Laboratory Medicine, Transfusion Services and Immunohematology, G. R. Doshi and K. M. Mehta Institute of Kidney Diseases & Research Centre (IKDRC), Dr. H.L. Trivedi Institute of Transplantation Sciences (ITS), Civil Hospital Campus, Asarwa, Ahmedabad, 380016, Gujarat, India,
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Rankin MM, Wilbur CJ, Rak K, Shields EJ, Granger A, Kushner JA. β-Cells are not generated in pancreatic duct ligation-induced injury in adult mice. Diabetes 2013; 62:1634-45. [PMID: 23349489 PMCID: PMC3636617 DOI: 10.2337/db12-0848] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The existence of adult β-cell progenitors remains the most controversial developmental biology topic in diabetes research. It has been reported that β-cell progenitors can be activated by ductal ligation-induced injury of adult mouse pancreas and apparently act in a cell-autonomous manner to double the functional β-cell mass within a week by differentiation and proliferation. Here, we demonstrate that pancreatic duct ligation (PDL) does not activate progenitors to contribute to β-cell mass expansion. Rather, PDL stimulates massive pancreatic injury, which alters pancreatic composition and thus complicates accurate measurement of β-cell content via traditional morphometry methodologies that superficially sample the pancreas. To overcome this potential bias, we quantified β-cells from the entire pancreas and observed that β-cell mass and insulin content are totally unchanged by PDL-induced injury. Lineage-tracing studies using sequential administration of thymidine analogs, rat insulin 2 promoter-driven cre-lox, and low-frequency ubiquitous cre-lox reveal that PDL does not convert progenitors to the β-cell lineage. Thus, we conclude that β-cells are not generated in injured adult mouse pancreas.
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Affiliation(s)
- Matthew M. Rankin
- Division of Endocrinology and Diabetes, Children’s Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Christopher J. Wilbur
- Division of Endocrinology and Diabetes, Children’s Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Kimberly Rak
- Division of Endocrinology and Diabetes, Children’s Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Emily J. Shields
- Division of Endocrinology and Diabetes, Children’s Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Anne Granger
- Division of Endocrinology and Diabetes, Children’s Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Jake A. Kushner
- McNair Medical Institute, Pediatric Diabetes and Endocrinology, Baylor College of Medicine, Houston, Texas
- Texas Children’s Diabetes and Endocrinology Center, Texas Children’s Hospital, Houston, Texas
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Jain S, Ruiz de Azua I, Lu H, White MF, Guettier JM, Wess J. Chronic activation of a designer G(q)-coupled receptor improves β cell function. J Clin Invest 2013; 123:1750-62. [PMID: 23478411 DOI: 10.1172/jci66432] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 01/17/2013] [Indexed: 12/12/2022] Open
Abstract
Type 2 diabetes (T2D) has emerged as a major threat to human health in most parts of the world. Therapeutic strategies aimed at improving pancreatic β cell function are predicted to prove beneficial for the treatment of T2D. In the present study, we demonstrate that drug-mediated, chronic, and selective activation of β cell G(q) signaling greatly improve β cell function and glucose homeostasis in mice. These beneficial metabolic effects were accompanied by the enhanced expression of many genes critical for β cell function, maintenance, and differentiation. By employing a combination of in vivo and in vitro approaches, we identified a novel β cell pathway through which receptor-activated G(q) leads to the sequential activation of ERK1/2 and IRS2 signaling, thus triggering a series of events that greatly improve β cell function. Importantly, we found that chronic stimulation of a designer G(q)-coupled receptor selectively expressed in β cells prevented both streptozotocin-induced diabetes and the metabolic deficits associated with the consumption of a high-fat diet in mice. Since β cells are endowed with numerous receptors that mediate their cellular effects via activation of G(q)-type G proteins, our findings provide a rational basis for the development of novel antidiabetic drugs targeting this class of receptors.
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Affiliation(s)
- Shalini Jain
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
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Nakamura A, Togashi Y, Orime K, Sato K, Shirakawa J, Ohsugi M, Kubota N, Kadowaki T, Terauchi Y. Control of beta cell function and proliferation in mice stimulated by small-molecule glucokinase activator under various conditions. Diabetologia 2012; 55:1745-54. [PMID: 22456697 DOI: 10.1007/s00125-012-2521-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 02/20/2012] [Indexed: 12/15/2022]
Abstract
AIMS/HYPOTHESIS We investigated changes in the expression of genes involved in beta cell function and proliferation in mouse islets stimulated with glucokinase activator (GKA) in order to elucidate the mechanisms by which GKA stimulates beta cell function and proliferation. METHODS Islets isolated from mice were used to investigate changes in the expression of genes related to beta cell function and proliferation stimulated by GKA. In addition, Irs2 knockout (Irs2 (-/-)) mice on a high-fat diet or a high-fat diet containing GKA were used to investigate the effects of GKA on beta cell proliferation in vivo. RESULTS In wild-type mice, Irs2 and Pdx1 expression was increased by GKA. In Irs2 (-/-) mice, GKA administration increased the glucose-stimulated secretion of insulin and Pdx1 expression, but not beta cell proliferation. It was particularly noteworthy that oxidative stress inhibited the upregulation of the Irs2 and Pdx1 genes induced by GKA. Moreover, whereas neither GKA alone nor exendin-4 alone upregulated the expression of Irs2 and Pdx1 in the islets of db/db mice, prior administration of exendin-4 to the mice caused GKA to increase the expression of these genes. CONCLUSIONS/INTERPRETATION GKA-stimulated IRS2 production affected beta cell proliferation but not beta cell function. Oxidative stress diminished the effects of GKA on the changes in expression of genes involved in beta cell function and proliferation. A combination of GKA and an incretin-related agent might therefore be effective in therapy.
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Affiliation(s)
- A Nakamura
- Department of Endocrinology and Metabolism, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
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Karadimos MJ, Kapoor A, El Khattabi I, Sharma A. β-cell preservation and regeneration for diabetes treatment: where are we now? ACTA ACUST UNITED AC 2012; 2:213-222. [PMID: 23049620 DOI: 10.2217/dmt.12.21] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Over the last decade, our knowledge of β-cell biology has expanded with the use of new scientific techniques and strategies. Growth factors, hormones and small molecules have been shown to enhance β-cell proliferation and function. Stem cell technology and research into the developmental biology of the pancreas have yielded new methods for in vivo and in vitro regeneration of β cells from stem cells and endogenous progenitors as well as transdifferentiation of non-β cells. Novel pharmacological approaches have been developed to preserve and enhance β-cell function. Strategies to increase expression of insulin gene transcription factors in dysfunctional and immature β cells have ameliorated these impairments. Hence, we suggest that strategies to minimize β-cell loss and to increase their function and regeneration will ultimately lead to therapy for both Type 1 and 2 diabetes.
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Affiliation(s)
- Michael J Karadimos
- Section of Islet Cell & Regenerative Biology, Joslin Diabetes Center, Boston, MA 02215, USA ; Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
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Wang Y, Liu Y, Wang H, Li C, Qi P, Bao J. Agaricus bisporus lectins mediates islet β-cell proliferation through regulation of cell cycle proteins. Exp Biol Med (Maywood) 2012; 237:287-96. [DOI: 10.1258/ebm.2011.011251] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This study was designed to determine the therapeutic effect of Agaricus bisporus lectins (ABL) by the regeneration of β-cells in mice following 70% partial pancreatectomy (PPx), and to explore the mechanisms of ABL-induced β-cell proliferation. Adult C57BL/6J mice were subjected to a 70% PPx operation or a sham operation, and mice received 10 mg/kg body weight of ABL or saline immediately after surgery. Blood glucose concentrations and insulin secretion levels were measured. To determine the growth rates of β-cells and duct cells, immunohistological analysis of pancreatic tissues was performed. Key cell cycle proteins and β-cell specific genes were measured by realtime polymerase chain reaction, Western blotting and immunohistological staining. In this study, a significant decrease in blood glucose concentrations, increase in glucose tolerance and expanded β-cell mass were observed in the ABL-treated mice. At the same time, after ABL treatment, increased β-cell proliferation rates were observed. Further studies on the expression of cyclin D1, cyclin D2 and Cdk4 demonstrated that these genes were significantly up-regulated in the ABL-treated mice. Meanwhile, Cdk4 activity was also enhanced. Moreover, the expression of PDX-1 (pancreatic and duodenal homeobox 1), Ngn3 (neurogenin 3), insulin, GLUT-1 (glucose transporter 1) and glucokinase was also increased in the ABL-treated mice. These findings demonstrate that ABL administration could partially reverse the impaired β-cell growth potential by regulating cell cycle proteins. Induction of islet β-cell proliferation by ABL suggests the therapeutic potential in preventing and/or treating diabetes.
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Affiliation(s)
- Yi Wang
- School of Life Science, Sichuan University, Chengdu, Sichuan 610064
- Institute of Organ Transplantation, Sichuan Academy of Medical Science & Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072
| | - Yuande Liu
- 91388 Military Hospital, Guangdong, Zhanjiang 524022, China
| | - Hailian Wang
- Institute of Organ Transplantation, Sichuan Academy of Medical Science & Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072
| | - Chunyang Li
- School of Life Science, Sichuan University, Chengdu, Sichuan 610064
| | - Ping Qi
- Institute of Organ Transplantation, Sichuan Academy of Medical Science & Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072
| | - Jinku Bao
- School of Life Science, Sichuan University, Chengdu, Sichuan 610064
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Abstract
Protecting the functional mass of insulin-producing β cells of the pancreas is a major therapeutic challenge in patients with type 1 (T1DM) or type 2 diabetes mellitus (T2DM). The gonadal hormone 17β-oestradiol (E2) is involved in reproductive, bone, cardiovascular and neuronal physiology. In rodent models of T1DM and T2DM, treatment with E2 protects pancreatic β cells against oxidative stress, amyloid polypeptide toxicity, lipotoxicity and apoptosis. Three oestrogen receptors (ERs)--ERα, ERβ and the G protein-coupled ER (GPER)--have been identified in rodent and human β cells. Whereas activation of ERα enhances glucose-stimulated insulin biosynthesis, reduces islet toxic lipid accumulation and promotes β-cell survival from proapoptotic stimuli, activation of ERβ increases glucose-stimulated insulin secretion. However, activation of GPER protects β cells from apoptosis, raises glucose-stimulated insulin secretion and lipid homeostasis without affecting insulin biosynthesis. Oestrogens are also improving islet engraftment in rodent models of pancreatic islet transplantation. This Review describes developments in the role of ERs in islet insulin biosynthesis and secretion, lipid homeostasis and survival. Moreover, we discuss why and how enhancing ER action in β cells without the undesirable effect of general oestrogen therapy is a therapeutic avenue to preserve functional β-cell mass in patients with diabetes mellitus.
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Affiliation(s)
- Joseph P Tiano
- Feinberg School of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine and Comprehensive Center on Obesity, Northwestern University, Chicago, IL 60611, USA
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Shen XX, Li HL, Pan L, Hong J, Xiao J, Hermansen K, Jeppesen PB, Li GW. Glucotoxicity and α cell dysfunction: involvement of the PI3K/Akt pathway in glucose-induced insulin resistance in rat islets and clonal αTC1-6 cells. Endocr Res 2012; 37:12-24. [PMID: 22007944 DOI: 10.3109/07435800.2011.610855] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIM/HYPOTHESIS The objective of this study was to assess how long-term exposure to high glucose affects the α cell function and whether the increased glucagon secretion is mediated via insulin resistance. MATERIALS AND METHODS We established a β cell-depleted rat model to obtain pure primary α cells. Furthermore, isolated rat islets and TC1-6 cells (a clonal α cell line) were exposed to high glucose (25 or 30 mmol/L) and low glucose (5.5 mmol/L) for up to 5 days to evaluate the influence of chronic glucose toxicity on glucagon secretion and glucagon gene expression. Moreover, we added insulin and/or Wortmannin to examine if the inhibitory effect of insulin on glucagon secretion was impaired by high glucose via the phosphatidylinositol 3 kinase/PKB protein kinase B pathway. RESULTS Both glucagon secretion and glucagon gene expression were increased in response to 5 days exposure to high glucose. While a moderate insulin concentration slightly inhibits glucagon secretion from rat islets and α TC1-6 cells at high glucose, a pronounced increase in glucagon secretion was observed at low glucose. We found that the insulin-mediated activity of the phosphatidylinositol 3 kinase/PKB protein kinase B pathway in the α cell was markedly impaired by chronic exposure to high glucose. CONCLUSION The hypersecretion of glucagon induced by glucotoxicity may be secondary to insulin resistance of the α cell induced by impaired activity of the insulin signaling pathway.
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Affiliation(s)
- Xiao-Xia Shen
- Endocrinology and Cardiac Disease Clinical Center, Fuwai Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, PR China.
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Khoo C, Yang J, Rajpal G, Wang Y, Liu J, Arvan P, Stoffers DA. Endoplasmic reticulum oxidoreductin-1-like β (ERO1lβ) regulates susceptibility to endoplasmic reticulum stress and is induced by insulin flux in β-cells. Endocrinology 2011; 152:2599-608. [PMID: 21540283 PMCID: PMC3115612 DOI: 10.1210/en.2010-1420] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Hyperglycemia increases insulin flux through the endoplasmic reticulum (ER) of pancreatic β-cells, and the unfolded protein response pathway is required to enhance insulin processing. Pancreatic and duodenal homeobox 1 (PDX1), a key pancreatic transcription factor, regulates insulin along with targets involved in insulin processing and secretion. Here we find that PDX1 is a direct transcriptional regulator of ER oxidoreductin-1-like β (Ero1lβ), which maintains the oxidative environment of the ER to facilitate disulfide bond formation. PDX1 deficiency reduced Ero1lβ transcript levels in mouse islets and mouse insulinoma (MIN6) cells; moreover, PDX1 occupied the Ero1lβ promoter in β-cells. ERO1lβ levels were induced by high glucose concentrations and by the reducing agent dithiothreitol, indicating potential roles in adaptation to increased oxidative protein folding load in the β-cell ER. In MIN6 cells, small interfering RNA-mediated silencing of Ero1lβ decreased insulin content and increased susceptibility to ER stress-induced apoptosis. These findings demonstrate roles for the PDX1 target ERO1lβ in maintaining insulin content and regulating cell survival during ER stress.
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Affiliation(s)
- Cynthia Khoo
- Institute for Diabetes, Obesity, and Metabolism and Department of Medicine, University of Pennsylvania School of Medicine, Clinical Research Building 726, 415 Curie Boulevard, Philadelphia, Pennsylvania 19104, USA
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Abstract
Insulin resistance is the most important pathophysiological feature in many pre-diabetic states. Type 2 diabetes mellitus is a complex metabolic disease and its pathogenesis involves abnormalities in both peripheral insulin action and insulin secretion by pancreatic beta cells. The creation of monogenic or polygenic genetically manipulated mice models in a tissue-specific manner was of great help to elucidate the tissue-specificity of insulin action and its contribution to the overall insulin resistance. However, complete understanding of the molecular bases of the insulin action and resistance requires the identification of the intracellular pathways that regulate insulin-stimulated proliferation, differentiation and metabolism. Accordingly, cell lines derived from insulin target tissues such as brown adipose tissue, liver and beta islets lacking insulin receptors or sensitive candidate genes such as IRS-1, IRS-2, IRS-3, IR and PTP1B were developed. Indeed, these cell lines have been also very useful to understand the tissue-specificity of insulin action and inaction.
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Affiliation(s)
- Manuel Benito
- Departamento de Bioquímica y Biología Molecular II, Facultad de Farmacia, Universidad Complutense, Madrid, Spain.
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Chen F, Zhu Y, Tang X, Sun Y, Jia W, Sun Y, Han X. Dynamic regulation of PDX-1 and FoxO1 expression by FoxA2 in dexamethasone-induced pancreatic β-cells dysfunction. Endocrinology 2011; 152:1779-88. [PMID: 21385937 DOI: 10.1210/en.2010-1048] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Transcription factors forkhead box (Fox)O1 and pancreatic and duodenal homeobox-1 (PDX-1) are involved in dexamethasone (DEX)-induced dysfunction in pancreatic β-cells. However, the molecular mechanism underlying the regulation of FoxO1 and PDX-1 expression in β-cells treated with DEX is not fully understood. In this study, we found that DEX markedly increased FoxO1 mRNA and protein expression, whereas it decreased PDX-1 mRNA and protein expression in a dose- and time-dependent manner. Further study showed that FoxA2 was involved in regulation of FoxO1 and PDX-1 expression in DEX-induced pancreatic β-cells dysfunction. Interestingly, we demonstrated for the first time that FoxA2 could bind to the FoxO1 gene promoter and positively regulate FoxO1 expression. Moreover, we found that DEX increased the activity of FoxA2 binding to the FoxO1 promoter but decreased the activity of FoxA2 binding to the PDX-1 promoter of RINm5F cells. Knockdown of FoxA2 by RNA interference inhibited FoxO1 expression and restored PDX-1 expression in pancreatic β-cells treated with DEX. However, DEX had no effect on the expression of FoxA2. Together, the results of the present study demonstrated that FoxA2 could dynamically regulate FoxO1 and PDX-1 expression in pancreatic β-cells treated with DEX, which provides new important information on the transcriptional regulation of FoxO1 and PDX-1 in DEX-induced pancreatic β-cells. Inhibition of FoxA2 can effectively protect β-cells against DEX-induced dysfunction.
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Affiliation(s)
- Fang Chen
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Clinical Diabetes Centre of Jiangsu Province, Nanjing Medical University, Nanjing 210029, China.
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