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PDX-1: A Promising Therapeutic Target to Reverse Diabetes. Biomolecules 2022; 12:biom12121785. [PMID: 36551213 PMCID: PMC9775243 DOI: 10.3390/biom12121785] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/18/2022] [Accepted: 11/19/2022] [Indexed: 12/02/2022] Open
Abstract
The pancreatic duodenum homeobox-1 (PDX-1) is a transcription factor encoded by a Hox-like homeodomain gene that plays a crucial role in pancreatic development, β-cell differentiation, and the maintenance of mature β-cell functions. Research on the relationship between PDX-1 and diabetes has gained much attention because of the increasing prevalence of diabetes melitus (DM). Recent studies have shown that the overexpression of PDX-1 regulates pancreatic development and promotes β-cell differentiation and insulin secretion. It also plays a vital role in cell remodeling, gene editing, and drug development. Conversely, the absence of PDX-1 increases susceptibility to DM. Therefore, in this review, we summarized the role of PDX-1 in pancreatic development and the pathogenesis of DM. A better understanding of PDX-1 will deepen our knowledge of the pathophysiology of DM and provide a scientific basis for exploring PDX-1 as a potential target for treating diabetes.
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Dos Santos RS, Medina-Gali RM, Babiloni-Chust I, Marroqui L, Nadal A. In Vitro Assays to Identify Metabolism-Disrupting Chemicals with Diabetogenic Activity in a Human Pancreatic β-Cell Model. Int J Mol Sci 2022; 23:ijms23095040. [PMID: 35563431 PMCID: PMC9102687 DOI: 10.3390/ijms23095040] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/21/2022] [Accepted: 04/29/2022] [Indexed: 11/22/2022] Open
Abstract
There is a need to develop identification tests for Metabolism Disrupting Chemicals (MDCs) with diabetogenic activity. Here we used the human EndoC-βH1 β-cell line, the rat β-cell line INS-1E and dispersed mouse islet cells to assess the effects of endocrine disruptors on cell viability and glucose-stimulated insulin secretion (GSIS). We tested six chemicals at concentrations within human exposure (from 0.1 pM to 1 µM). Bisphenol-A (BPA) and tributyltin (TBT) were used as controls while four other chemicals, namely perfluorooctanoic acid (PFOA), triphenylphosphate (TPP), triclosan (TCS) and dichlorodiphenyldichloroethylene (DDE), were used as “unknowns”. Regarding cell viability, BPA and TBT increased cell death as previously observed. Their mode of action involved the activation of estrogen receptors and PPARγ, respectively. ROS production was a consistent key event in BPA-and TBT-treated cells. None of the other MDCs tested modified viability or ROS production. Concerning GSIS, TBT increased insulin secretion while BPA produced no effects. PFOA decreased GSIS, suggesting that this chemical could be a “new” diabetogenic agent. Our results indicate that the EndoC-βH1 cell line is a suitable human β-cell model for testing diabetogenic MDCs. Optimization of the test methods proposed here could be incorporated into a set of protocols for the identification of MDCs.
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Affiliation(s)
- Reinaldo Sousa Dos Santos
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche, 03202 Elche, Spain; (R.S.D.S.); (R.M.M.-G.); (I.B.-C.); (L.M.)
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Regla María Medina-Gali
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche, 03202 Elche, Spain; (R.S.D.S.); (R.M.M.-G.); (I.B.-C.); (L.M.)
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Ignacio Babiloni-Chust
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche, 03202 Elche, Spain; (R.S.D.S.); (R.M.M.-G.); (I.B.-C.); (L.M.)
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Laura Marroqui
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche, 03202 Elche, Spain; (R.S.D.S.); (R.M.M.-G.); (I.B.-C.); (L.M.)
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Angel Nadal
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche, 03202 Elche, Spain; (R.S.D.S.); (R.M.M.-G.); (I.B.-C.); (L.M.)
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Correspondence:
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Alhaidan Y, Christesen HT, Lundberg E, Balwi MAA, Brusgaard K. CRISPR/Cas9 ADCY7 Knockout Stimulates the Insulin Secretion Pathway Leading to Excessive Insulin Secretion. Front Endocrinol (Lausanne) 2021; 12:657873. [PMID: 34177802 PMCID: PMC8231291 DOI: 10.3389/fendo.2021.657873] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 05/18/2021] [Indexed: 11/15/2022] Open
Abstract
AIM Despite the enormous efforts to understand Congenital hyperinsulinism (CHI), up to 50% of the patients are genetically unexplained. We aimed to functionally characterize a novel candidate gene in CHI. PATIENT A 4-month-old boy presented severe hyperinsulinemic hypoglycemia. A routine CHI genetic panel was negative. METHODS A trio-based whole-exome sequencing (WES) was performed. Gene knockout in the RIN-m cell line was established by CRISPR/Cas9. Gene expression was performed using real-time PCR. RESULTS Hyperinsulinemic hypoglycemia with diffuse beta-cell involvement was demonstrated in the patient, who was diazoxide-responsive. By WES, compound heterozygous variants were identified in the adenylyl cyclase 7, ADCY7 gene p.(Asp439Glu) and p.(Gly1045Arg). ADCY7 is calcium-sensitive, expressed in beta-cells and converts ATP to cAMP. The variants located in the cytoplasmic domains C1 and C2 in a highly conserved and functional amino acid region. RIN-m(-/-Adcy7) cells showed a significant increase in insulin secretion reaching 54% at low, and 49% at high glucose concentrations, compared to wild-type. In genetic expression analysis Adcy7 loss of function led to a 34.1-fold to 362.8-fold increase in mRNA levels of the insulin regulator genes Ins1 and Ins2 (p ≤ 0.0002), as well as increased glucose uptake and sensing indicated by higher mRNA levels of Scl2a2 and Gck via upregulation of Pdx1, and Foxa2 leading to the activation of the glucose stimulated-insulin secretion (GSIS) pathway. CONCLUSION This study identified a novel candidate gene, ADCY7, to cause CHI via activation of the GSIS pathway.
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Affiliation(s)
- Yazeid Alhaidan
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
- Department of Medical Genomics Research, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- *Correspondence: Yazeid Alhaidan,
| | - Henrik Thybo Christesen
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
- Hans Christian Andersen Children’s Hospital, Odense University Hospital, Odense, Denmark
- Odense Pancreas Center, Odense, Denmark
| | - Elena Lundberg
- Institute of Clinical Science, Pediatrics, Umea University, Umeå, Sweden
| | - Mohammed A. Al Balwi
- Department of Medical Genomics Research, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, NGHA, Riyadh, Saudi Arabia
| | - Klaus Brusgaard
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
- Near East University, Nicosia, Cyprus
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Goenka V, Borkar T, Desai A, Das RK. Therapeutic potential of mesenchymal stem cells in treating both types of diabetes mellitus and associated diseases. J Diabetes Metab Disord 2020; 19:1979-1993. [PMID: 33520872 PMCID: PMC7843693 DOI: 10.1007/s40200-020-00647-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 09/24/2020] [Indexed: 10/23/2022]
Abstract
Diabetes mellitus is a common lifestyle disease which can be classified into type 1 diabetes mellitus and type 2 diabetes mellitus. While both result in hyperglycemia due to lack of insulin action and further associated chronic ailments, there is a marked distinction in the cause for each type due to which both require a different prophylaxis. As observed, type 1 diabetes is caused due to the autoimmune action of the body resulting in the destruction of pancreatic islet cells. On the other hand, type 2 diabetes is caused either due to insulin resistance of target cells or lack of insulin production as per physiological requirements. Attempts to cure the disease have been made by bringing drastic changes in the patients' lifestyle; parenteral administration of insulin; prescription of drugs such as biguanides, meglitinides, and amylin; pancreatic transplantation; and immunotherapy. While these attempts cause a certain degree of relief to the patient, none of these can cure diabetes mellitus. However, a new treatment strategy led by the discovery of mesenchymal stem cells and their unique immunomodulatory and multipotent properties has inspired therapies to treat diabetes by essentially reversing the conditions causing the disease. The current review aims to enumerate the role of various mesenchymal stem cells and the different approaches to treat both types of diabetes and its associated diseases as well.
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Affiliation(s)
- Vidul Goenka
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu India
| | - Tanhai Borkar
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu India
| | - Aska Desai
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu India
| | - Raunak Kumar Das
- Centre for Biomaterials, Cellular and Molecular Theranostics, Vellore Institute of Technology, Vellore, Tamil Nadu India
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Berger C, Zdzieblo D. Glucose transporters in pancreatic islets. Pflugers Arch 2020; 472:1249-1272. [PMID: 32394191 PMCID: PMC7462922 DOI: 10.1007/s00424-020-02383-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 02/07/2023]
Abstract
The fine-tuning of glucose uptake mechanisms is rendered by various glucose transporters with distinct transport characteristics. In the pancreatic islet, facilitative diffusion glucose transporters (GLUTs), and sodium-glucose cotransporters (SGLTs) contribute to glucose uptake and represent important components in the glucose-stimulated hormone release from endocrine cells, therefore playing a crucial role in blood glucose homeostasis. This review summarizes the current knowledge about cell type-specific expression profiles as well as proven and putative functions of distinct GLUT and SGLT family members in the human and rodent pancreatic islet and further discusses their possible involvement in onset and progression of diabetes mellitus. In context of GLUTs, we focus on GLUT2, characterizing the main glucose transporter in insulin-secreting β-cells in rodents. In addition, we discuss recent data proposing that other GLUT family members, namely GLUT1 and GLUT3, render this task in humans. Finally, we summarize latest information about SGLT1 and SGLT2 as representatives of the SGLT family that have been reported to be expressed predominantly in the α-cell population with a suggested functional role in the regulation of glucagon release.
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Affiliation(s)
- Constantin Berger
- Tissue Engineering & Regenerative Medicine, University Hospital Würzburg, Röntgenring 11, 97070, Würzburg, Germany
| | - Daniela Zdzieblo
- Tissue Engineering & Regenerative Medicine, University Hospital Würzburg, Röntgenring 11, 97070, Würzburg, Germany.
- Fraunhofer Institute for Silicate Research (ISC), Translational Center Regenerative Therapies, Neunerplatz 2, 97082, Würzburg, Germany.
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Jara MA, Werneck-De-Castro JP, Lubaczeuski C, Johnson JD, Bernal-Mizrachi E. Pancreatic and duodenal homeobox-1 (PDX1) contributes to β-cell mass expansion and proliferation induced by Akt/PKB pathway. Islets 2020; 12:32-40. [PMID: 32876522 PMCID: PMC7527019 DOI: 10.1080/19382014.2020.1762471] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Maintenance of pancreatic β-cell mass and function is fundamental to glucose homeostasis and to prevent diabetes. The PI3 K-Akt-mTORC1 pathway is critical for β-cells mass and function, while PDX1 has been implicated in β-cell development, maturation, and function. Here we tested whether Akt signaling requires PDX1 expression to regulate β-cell mass, proliferation, and glucose homeostasis. In order to address that, we crossed a mouse model overexpressing constitutively active Akt mutant in β-cells (β-caAkt) with mice lacking one allele of PDX1gene (β-caAkt/pdx1+/-). While the β-caAkt mice exhibit higher plasma insulin levels, greater β-cell mass and improved glucose tolerance compared to control mice, the β-caAkt/pdx1+/- mice are hyperglycemic and intolerant to glucose. The changes in glucose homeostasis in β-caAkt/pdx1+/- were associated with a 60% reduction in β-cell mass compared to β-caAkt mice. The impaired β-cell mass in the β-caAkt/pdx1+/- mice can be explained by a lesser β-cell proliferation measured by the number of Ki67 positive β-cells. We did not observe any differences in apoptosis between β-caAkt/pdx1+/- and β-caAkt mice. In conclusion, PDX1 contributes to β-cell mass expansion and glucose metabolism induced by activation of Akt signaling.
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Affiliation(s)
- Mark Anthony Jara
- Department of Internal Medicine, Division of Endocrinology, Diabetes and Metabolism, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Joao Pedro Werneck-De-Castro
- Department of Internal Medicine, Division of Endocrinology, Diabetes and Metabolism, Miller School of Medicine, University of Miami, Miami, FL, USA
- Miami VA Health Care System, Miami, FL, USA
| | - Camila Lubaczeuski
- Department of Internal Medicine, Division of Endocrinology, Diabetes and Metabolism, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - James D. Johnson
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
| | - Ernesto Bernal-Mizrachi
- Department of Internal Medicine, Division of Endocrinology, Diabetes and Metabolism, Miller School of Medicine, University of Miami, Miami, FL, USA
- Miami VA Health Care System, Miami, FL, USA
- CONTACT Ernesto Bernal-Mizrachi Department Of Internal Medicine, Division Of Endocrinology, Diabetes and Metabolism, University of Miami Miller School of Medicine, Miami, FL33136, USA
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Aydın S, Demirci S, Doğan A, Sağraç D, Kaşıkcı E, Şahin F. Boron containing compounds promote the survival and the maintenance of pancreatic β-cells. Mol Biol Rep 2019; 46:5465-5478. [PMID: 31368021 DOI: 10.1007/s11033-019-05002-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 07/24/2019] [Indexed: 01/11/2023]
Abstract
Diabetes mellitus is worldwide disease. The life of diabetic patients are dependent on exogenous insulin. Pancreas or particularly islet transplantations are performed for reducing external insulin dependency. External substances are also used to protect the β-cells from the death or increase insulin secretion. In the current study, two different boron containing compounds (sodium pentaborate pentahydrate-NaB and boric acid-BA) were investigated for their effect on pancreatic cells in terms of pro-apoptotic and anti-apoptotic markers, genes related to insulin production mechanism, pancreatic development and glucose metabolism, some antioxidant enzymes, and genes for the initiation of diabetes, insulin secretion and antioxidant enzyme activities in vitro. The results revealed that boron containing compounds did not lead to apoptosis. On the contrary, they increased cell viability, antioxidant enzyme activities and the level of genes related to insulin production. Overall evaluation, data in the current study showed that boron containing compounds might be promising therapeutic agents for type 1 diabetes. However, additional investigations are strictly needed to elucidate molecular mechanisms of boron containing compounds.
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Affiliation(s)
- Safa Aydın
- Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Yeditepe University, Istanbul, Turkey
| | - Selami Demirci
- Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes and National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ayşegül Doğan
- Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Yeditepe University, Istanbul, Turkey
| | - Derya Sağraç
- Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Yeditepe University, Istanbul, Turkey
| | - Ezgi Kaşıkcı
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Fikrettin Şahin
- Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Yeditepe University, Istanbul, Turkey.
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8
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Horiguchi M, Yoshida M, Hirata K, Furuyama K, Masui T, Uemoto S, Kawaguchi Y. Senescence caused by inactivation of the homeodomain transcription factor Pdx1 in adult pancreatic acinar cells in mice. FEBS Lett 2019; 593:2226-2234. [PMID: 31240701 DOI: 10.1002/1873-3468.13504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/04/2019] [Accepted: 06/16/2019] [Indexed: 11/11/2022]
Abstract
In this study, we used tamoxifen-inducible Elastase-Cre-mediated inactivation of pancreatic and duodenal homeobox1 (Pdx1), an indispensable gene during embryonic pancreatogenesis, to investigate the role of Pdx1 in adult pancreatic exocrine tissue. We found that Pdx1 depletion in approximately 50% of acinar cell mass did not show any macroscopic phenotype. Lineage tracing experiments revealed that the percentage of Pdx1-depleted cells did not change initially but gradually decreased, while the proliferation of Pdx1-preserved cells increased. Electron microscopic analysis showed the emergence of round-shaped mitochondria with less cristae, dilated ER lumen and increased number of autophagosomes but no apoptosis. Instead, Pdx1-depleted acinar cells became senescent. These findings indicate that intracellular stress caused by Pdx1 inactivation triggers the senescence-associated secretory phenotype to maintain organ homeostasis in this model.
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Affiliation(s)
- Masashi Horiguchi
- Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Clinical Application, Center for iPS cell Research and Application, Kyoto, Japan
| | - Masahiro Yoshida
- Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Clinical Application, Center for iPS cell Research and Application, Kyoto, Japan
| | - Koji Hirata
- Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Clinical Application, Center for iPS cell Research and Application, Kyoto, Japan
| | - Kenichiro Furuyama
- Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Clinical Application, Center for iPS cell Research and Application, Kyoto, Japan
| | - Toshihiko Masui
- Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Clinical Application, Center for iPS cell Research and Application, Kyoto, Japan
| | - Shinji Uemoto
- Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yoshiya Kawaguchi
- Department of Clinical Application, Center for iPS cell Research and Application, Kyoto, Japan
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9
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Rout M, Lulu S S. Molecular and disease association of gestational diabetes mellitus affected mother and placental datasets reveal a strong link between insulin growth factor (IGF) genes in amino acid transport pathway: A network biology approach. J Cell Biochem 2019; 120:1577-1587. [PMID: 30335885 DOI: 10.1002/jcb.27418] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 07/12/2018] [Indexed: 01/24/2023]
Abstract
Discerning the relationship between molecules involved in diseases based on their underlying biological mechanisms is one of the greatest challenges in therapeutic development today. Gestational diabetes mellitus (GDM) is one of the most common complications during pregnancy, which adversely affects both mothers and offspring during and after pregnancy. We have constructed two datasets of (GDM associated genes from affected mother and placenta to systematically analyze and evaluate their interactions like gene-gene, gene-protein, gene-microRNA (miRNA), gene-transcription factors, and gene-associated diseases to enhance our current knowledge, which may lead to further advancements in disease diagnosis, prognosis, and treatment. The results identify the key genes with respect to maternal dataset as insulin receptor, insulin (INS), leptin (LEP), glucokinase, and hepatocyte nuclear factor 1 alpha, whereas from placenta include insulin-like growth factor 1, growth hormone receptor, and breast cancer anti-estrogen resistance protein 1, which are found to be highly enriched in pancreas, ovary, adipocyte, heart, and placental tissues. The key transcription factors include Sp1 transcription factor, pancreatic and duodenal homeobox 1, and hepatocyte nuclear factor 4 alpha, whereas miRNA includes has-miR-5699-5p and has-miR-3158-3p. The study also reveals that GDM has associations with diseases like type I and II diabetes mellitus, obesity, and preeclampsia. More significantly, we could trace out a significant connection between the key molecules like LEP and placental growth hormone from mother and placental dataset, which plays a critical role in INS secretion, INS signaling, and β-cell dysfunction pathways.
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Affiliation(s)
- Madhusmita Rout
- Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Sajitha Lulu S
- Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, India
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10
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Lupin gamma conglutin protein: effect on Slc2a2, Gck and Pdx-1 gene expression and GLUT2 levels in diabetic rats. REVISTA BRASILEIRA DE FARMACOGNOSIA-BRAZILIAN JOURNAL OF PHARMACOGNOSY 2018. [DOI: 10.1016/j.bjp.2018.08.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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11
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Lu B, Kurmi K, Munoz-Gomez M, Jacobus Ambuludi EJ, Tonne JM, Rakshit K, Hitosugi T, Kudva YC, Matveyenko AV, Ikeda Y. Impaired β-cell glucokinase as an underlying mechanism in diet-induced diabetes. Dis Model Mech 2018; 11:dmm033316. [PMID: 29915142 PMCID: PMC6031355 DOI: 10.1242/dmm.033316] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 04/26/2018] [Indexed: 12/22/2022] Open
Abstract
High-fat diet (HFD)-fed mouse models have been widely used to study early type 2 diabetes. Decreased β-cell glucokinase (GCK) expression has been observed in HFD-induced diabetes. However, owing to its crucial roles in glucose metabolism in the liver and in islet β-cells, the contribution of decreased GCK expression to the development of HFD-induced diabetes is unclear. Here, we employed a β-cell-targeted gene transfer vector and determined the impact of β-cell-specific increase in GCK expression on β-cell function and glucose handling in vitro and in vivo Overexpression of GCK enhanced glycolytic flux, ATP-sensitive potassium channel activation and membrane depolarization, and increased proliferation in Min6 cells. β-cell-targeted GCK transduction did not change glucose handling in chow-fed C57BL/6 mice. Although adult mice fed a HFD showed reduced islet GCK expression, impaired glucose tolerance and decreased glucose-stimulated insulin secretion (GSIS), β-cell-targeted GCK transduction improved glucose tolerance and restored GSIS. Islet perifusion experiments verified restored GSIS in isolated HFD islets by GCK transduction. Thus, our data identify impaired β-cell GCK expression as an underlying mechanism for dysregulated β-cell function and glycemic control in HFD-induced diabetes. Our data also imply an etiological role of GCK in diet-induced diabetes.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Brian Lu
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Virology and Gene Therapy Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN 55905, USA
| | - Kiran Kurmi
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Molecular Pharmacology and Experimental Therapeutics Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN 55905, USA
| | | | | | - Jason M Tonne
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Kuntol Rakshit
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA
| | - Taro Hitosugi
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA
| | - Yogish C Kudva
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic, Rochester, MN 55905, USA
| | - Aleksey V Matveyenko
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA
| | - Yasuhiro Ikeda
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
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12
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Pancreatic Inflammation Redirects Acinar to β Cell Reprogramming. Cell Rep 2017; 17:2028-2041. [PMID: 27851966 DOI: 10.1016/j.celrep.2016.10.068] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 09/06/2016] [Accepted: 10/19/2016] [Indexed: 12/11/2022] Open
Abstract
Using a transgenic mouse model to express MafA, Pdx1, and Neurog3 (3TF) in a pancreatic acinar cell- and doxycycline-dependent manner, we discovered that the outcome of transcription factor-mediated acinar to β-like cellular reprogramming is dependent on both the magnitude of 3TF expression and on reprogramming-induced inflammation. Overly robust 3TF expression causes acinar cell necrosis, resulting in marked inflammation and acinar-to-ductal metaplasia. Generation of new β-like cells requires limiting reprogramming-induced inflammation, either by reducing 3TF expression or by eliminating macrophages. The new β-like cells were able to reverse streptozotocin-induced diabetes 6 days after inducing 3TF expression but failed to sustain their function after removal of the reprogramming factors.
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13
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Yamamoto Y, Miyatsuka T, Sasaki S, Miyashita K, Kubo F, Shimo N, Takebe S, Watada H, Kaneto H, Matsuoka TA, Shimomura I. Preserving expression of Pdx1 improves β-cell failure in diabetic mice. Biochem Biophys Res Commun 2016; 483:418-424. [PMID: 28017717 DOI: 10.1016/j.bbrc.2016.12.128] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 02/01/2023]
Abstract
Pdx1, a β-cell-specific transcription factor, has been shown to play a crucial role in maintaining β-cell function through transactivation of β-cell-related genes. In addition, it has been reported that the expression levels of Pdx1 are compromised under diabetic conditions in human and rodent models. We therefore aimed to clarify the possible beneficial role of Pdx1 against β-cell failure and generated the transgenic mouse that expressed Pdx1 conditionally and specifically in β cells (βPdx1) and crossed these mice with Ins2Akita diabetic mice. Whereas Pdx1 mRNA levels were reduced in Ins2Akita mice compared with their non-diabetic littermates, the mRNA levels of Pdx1 were significantly recovered in the islets of βPdx1; Ins2Akita mice. The βPdx1; Ins2Akita mice exhibited significantly improved glucose tolerance, compared with control Ins2Akita littermates, accompanied by increased insulin secretion after glucose loading. Furthermore, histological examination demonstrated that βPdx1; Ins2Akita mice had improved localization of SLC2A2 (GLUT2), and quantitative RT-PCR showed the recovered expression of Mafa and Gck mRNAs in the islets of βPdx1; Ins2Akita mice. These findings suggest that the sustained expression of Pdx1 improves β-cell failure in Ins2Akita mice, at least partially through the preserving expression of β-cell-specific genes as well as improved localization of GLUT2.
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Affiliation(s)
- Yuichi Yamamoto
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Takeshi Miyatsuka
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan; Department of Metabolism and Endocrinology, Juntendo University, Graduate School of Medicine, Tokyo, Japan.
| | - Shugo Sasaki
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Kazuyuki Miyashita
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Fumiyo Kubo
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Naoki Shimo
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Satomi Takebe
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Hirotaka Watada
- Department of Metabolism and Endocrinology, Juntendo University, Graduate School of Medicine, Tokyo, Japan
| | - Hideaki Kaneto
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Taka-Aki Matsuoka
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Iichiro Shimomura
- Department of Metabolic Medicine, Osaka University, Graduate School of Medicine, Osaka, Japan
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14
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Zhang Y, Feng F, Chen T, Li Z, Shen QW. Antidiabetic and antihyperlipidemic activities of Forsythia suspensa (Thunb.) Vahl (fruit) in streptozotocin-induced diabetes mice. JOURNAL OF ETHNOPHARMACOLOGY 2016; 192:256-263. [PMID: 27377336 DOI: 10.1016/j.jep.2016.07.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 06/03/2016] [Accepted: 07/01/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The fruit of Forsythia suspense (Thunb.) Vahl, a well-known Chinese Materia Medica, has been traditionally used in traditional Chinese medicine for the treatment of diabetes and some other diseases, but the rational for the usage of this plant is unclear. The aim of this study was to investigate the therapeutic effect and potential mechanism of the fruit of F. suspensa using streptozotocin (STZ)-induced diabetic mice. MATERIALS AND METHODS Crude methanol extract of F. suspense fruit was fractionated with different solvents and the ethyl acetate fraction (EAF) was selected for in vivo studies based on the in vitro α-amylase and HMG-CoA reductase (3-hydroxy-3-methyl-glutaryl coenzyme A) inhibiting activities. For in vivo study, diabetes mellitus was induced in mice with STZ. Diabetic mice were orally administrated with 50, 100 and 200mg/kg body weight of EAF for 4 weeks. Mouse body weight, blood glucose, glucose tolerance, biochemical parameters and gene expression related to pancreas and liver function were analyzed after EAF administration. RESULTS After 4 weeks of EAF intervention, a significant decrease in blood glucose, triglyceride, creatinine total cholesterol, acid phosphatase, alkaline phosphatase, aspartate transaminase, alanine transaminase, and hepatic lipid (triglycerides and cholesterol) content as well as a significant increase in body weight, insulin secretion and glucose tolerance was observed in EAF treated diabetic mice. qRT-PCR analysis revealed that EAF antagonized STZ-induced alteration of the expression of rate-limiting enzymes (glucokinase and phosphorenolpyruvate carboxykinase) in liver and insulin secretion related genes insulin-1, insulin-2 and duodenal homeobox factor-1 in pancreas. CONCLUSION The ethyl acetate extract of Forsythia suspense (Thunb.) Vahl fruit has potency to develop an antihyperglycemic and antihyperlipidemic agent for the treatment of diabetes mellitus via modulation of oxidative stress, the hepatic glucose metabolism and pancreatic insulin secretion.
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Affiliation(s)
- Yanyan Zhang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fu Feng
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ting Chen
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zhongwen Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Qingwu W Shen
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China; College of Food Science and Technology, Hunan Agricultural University, Changsha, Hunan 410128, China.
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15
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Diabetes Caused by Elastase-Cre-Mediated Pdx1 Inactivation in Mice. Sci Rep 2016; 6:21211. [PMID: 26887806 PMCID: PMC4758062 DOI: 10.1038/srep21211] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/19/2016] [Indexed: 02/06/2023] Open
Abstract
Endocrine and exocrine pancreas tissues are both derived from the posterior foregut endoderm, however, the interdependence of these two cell types during their formation is not well understood. In this study, we generated mutant mice, in which the exocrine tissue is hypoplastic, in order to reveal a possible requirement for exocrine pancreas tissue in endocrine development and/or function. Since previous studies showed an indispensable role for Pdx1 in pancreas organogenesis, we used Elastase-Cre-mediated recombination to inactivate Pdx1 in the pancreatic exocrine lineage during embryonic stages. Along with exocrine defects, including impaired acinar cell maturation, the mutant mice exhibited substantial endocrine defects, including disturbed tip/trunk patterning of the developing ductal structure, a reduced number of Ngn3-expressing endocrine precursors, and ultimately fewer β cells. Notably, postnatal expansion of the endocrine cell content was extremely poor, and the mutant mice exhibited impaired glucose homeostasis. These findings suggest the existence of an unknown but essential factor(s) in the adjacent exocrine tissue that regulates proper formation of endocrine precursors and the expansion and function of endocrine tissues during embryonic and postnatal stages.
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16
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Chen F, Sha M, Wang Y, Wu T, Shan W, Liu J, Zhou W, Zhu Y, Sun Y, Shi Y, Bleich D, Han X. Transcription factor Ets-1 links glucotoxicity to pancreatic beta cell dysfunction through inhibiting PDX-1 expression in rodent models. Diabetologia 2016; 59:316-24. [PMID: 26564177 DOI: 10.1007/s00125-015-3805-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Accepted: 10/14/2015] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS 'Glucotoxicity' is a term used to convey the negative effect of hyperglycaemia on beta cell function; however, the underlying molecular mechanisms that impair insulin secretion and gene expression are poorly defined. Our objective was to define the role of transcription factor v-ets avian erythroblastosis virus E26 oncogene homologue 1 (Ets-1) in beta cell glucotoxicity. METHODS Primary islets and Min6 cells were exposed to high glucose and Ets-1 expression was measured. Recombinant adenovirus and transgenic mice were used to upregulate Ets-1 expression in beta cells in vitro and in vivo, and insulin secretion was assessed. The binding activity of H3/H4 histone on the Ets-1 promoter, and that of forkhead box (FOX)A2, FOXO1 and Ets-1 on the Pdx-1 promoter was measured by chromatin immunoprecipitation and quantitative real-time PCR assay. RESULTS High glucose induced upregulation of Ets-1 expression and hyperacetylation of histone H3 and H4 at the Ets-1 gene promoter in beta cells. Ets-1 overexpression dramatically suppressed insulin secretion and biosynthesis both in vivo and in vitro. Besides, Ets-1 overexpression increased the activity of FOXO1 but decreased that of FOXA2 binding to the pancreatic and duodenal homeobox 1 (PDX-1) homology region 2 (PH2), resulting in inhibition of Pdx-1 promoter activity and downregulation of PDX-1 expression and activity. In addition, high glucose promoted the interaction of Ets-1 and FOXO1, and the activity of Ets-1 binding to the Pdx-1 promoter. Importantly, PDX-1 overexpression reversed the defect in pancreatic beta cells induced by Ets-1 excess, while knockdown of Ets-1 prevented hyperglycaemia-induced dysfunction of pancreatic beta cells. CONCLUSIONS/INTERPRETATION Our observations suggest that Ets-1 links glucotoxicity to pancreatic beta cell dysfunction through inhibiting PDX-1 expression in type 2 diabetes.
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MESH Headings
- Animals
- Blood Glucose/physiology
- Cells, Cultured
- Diabetes Mellitus, Experimental/blood
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/physiopathology
- Diabetes Mellitus, Type 2/complications
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/physiopathology
- Gene Expression Regulation
- Homeodomain Proteins/genetics
- Homeodomain Proteins/metabolism
- Hyperglycemia/blood
- Hyperglycemia/genetics
- Hyperglycemia/physiopathology
- Insulin-Secreting Cells/metabolism
- Insulin-Secreting Cells/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Proto-Oncogene Protein c-ets-1/physiology
- Rats
- Rats, Sprague-Dawley
- Trans-Activators/genetics
- Trans-Activators/metabolism
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Affiliation(s)
- Fang Chen
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Min Sha
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Yanyang Wang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Tijun Wu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Wei Shan
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Jia Liu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Wenbo Zhou
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Yunxia Zhu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Yujie Sun
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China
| | - Yuguang Shi
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center, San Antonio, TX, USA
| | - David Bleich
- Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Xiao Han
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, People's Republic of China.
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17
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Uncovering the mechanisms of beta-cell neogenesis and maturation toward development of a regenerative therapy for diabetes. Diabetol Int 2015. [DOI: 10.1007/s13340-015-0233-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Kaneto H, Matsuoka TA. Role of pancreatic transcription factors in maintenance of mature β-cell function. Int J Mol Sci 2015; 16:6281-97. [PMID: 25794287 PMCID: PMC4394532 DOI: 10.3390/ijms16036281] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/10/2015] [Accepted: 02/16/2015] [Indexed: 12/12/2022] Open
Abstract
A variety of pancreatic transcription factors including PDX-1 and MafA play crucial roles in the pancreas and function for the maintenance of mature β-cell function. However, when β-cells are chronically exposed to hyperglycemia, expression and/or activities of such transcription factors are reduced, which leads to deterioration of β-cell function. These phenomena are well known as β-cell glucose toxicity in practical medicine as well as in the islet biology research area. Here we describe the possible mechanism for β-cell glucose toxicity found in type 2 diabetes. It is likely that reduced expression levels of PDX-1 and MafA lead to suppression of insulin biosynthesis and secretion. In addition, expression levels of incretin receptors (GLP-1 and GIP receptors) in β-cells are decreased, which likely contributes to the impaired incretin effects found in diabetes. Taken together, down-regulation of insulin gene transcription factors and incretin receptors explains, at least in part, the molecular mechanism for β-cell glucose toxicity.
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Affiliation(s)
- Hideaki Kaneto
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577, Matsushima, Kurashiki 701-0192, Japan.
| | - Taka-aki Matsuoka
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan.
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19
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Wang H, Shi S, Bao B, Li X, Wang S. Structure characterization of an arabinogalactan from green tea and its anti-diabetic effect. Carbohydr Polym 2015; 124:98-108. [PMID: 25839799 DOI: 10.1016/j.carbpol.2015.01.070] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 01/17/2015] [Accepted: 01/26/2015] [Indexed: 12/26/2022]
Abstract
A water-soluble polysaccharide, 7WA, with an average molecular mass of 7.1×10(4)Da, was isolated from the leaves of green tea. Monosaccharide composition analysis indicated that 7WA mainly contained Arabinose and Galactose in the molar ratio of 1.0:0.96. By using the methods of methylation analysis, partial hydrolysis, and NMR, 7WA was characterized to possess a backbone consisting of 1,3- and 1,6-linked galactopyranosyl residues, with branches attached to O-3 of 1,6-linked galactose residues, and O-4 and O-6 of 1,3-linked galactose residues. The results of glucose-stimulated insulin secretion (GSIS) showed that 7WA significantly augmented insulin secretion at high glucose level (25mM), however, such effect was not seen at low glucose level (5mM). The mechanism study results indicated 7WA, a type II arabinogalactan from Green Tea, enhances GSIS through cAMP-PKA pathway.
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Affiliation(s)
- Huijun Wang
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SATCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, PR China
| | - Songshan Shi
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SATCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, PR China
| | - Bin Bao
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SATCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, PR China
| | - Xiaojun Li
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SATCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, PR China
| | - Shunchun Wang
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SATCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, PR China.
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20
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Kong X, Zhang L, Hua X, Ma X. Squamosamide Derivative FLZ Protects Pancreatic β-Cells from Glucotoxicity by Stimulating Akt-FOXO1 Pathway. J Diabetes Res 2015; 2015:803986. [PMID: 26167511 PMCID: PMC4488173 DOI: 10.1155/2015/803986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 04/29/2015] [Indexed: 01/17/2023] Open
Abstract
Chronic hyperglycemia increases apoptosis and reduces glucose-stimulated insulin secretion. Although protective agents have been searched extensively, none has been found so far. Here we tested FLZ, a synthetic derivative of squamosamide from a Chinese herb, as a potential candidate for antiglucotoxicity in INS-1E cells and mouse islets. Chronic culture of β-cells in 30 mM glucose caused progressive reduction of cell viability, accompanied with increased apoptosis and reduced insulin secretion. These effects on apoptosis and insulin were reversed by FLZ in a dose-dependent manner. FLZ treatment also increased forkhead box O1 protein phosphorylation and reduced its nuclear location. On the contrary, FLZ increased pancreatic and duodenal homeobox-1 expression and its nuclear localization, an effect mediated by increased p-Akt. Consistently, Akt selective inhibitor MK-2206 completely abolished antiglucotoxicity effect of FLZ. Furthermore, FLZ treatment increased cytosolic ATP/ADP ratio. Taken together, our results suggest that FLZ could be a potential therapeutic agent to treat the hyperglycemia-induced β-cell failure.
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Affiliation(s)
- Xiangchen Kong
- Diabetes Center, Shenzhen University, Shenzhen 518060, China
| | - Longmei Zhang
- Diabetes Center, Shenzhen University, Shenzhen 518060, China
| | - Xianxin Hua
- Diabetes Center, Shenzhen University, Shenzhen 518060, China
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Xiaosong Ma
- Diabetes Center, Shenzhen University, Shenzhen 518060, China
- *Xiaosong Ma:
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21
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Kim JY, Hwang JY, Lee DY, Song EH, Park KJ, Kim GH, Jeong EA, Lee YJ, Go MJ, Kim DJ, Lee SS, Kim BJ, Song J, Roh GS, Gao B, Kim WH. Chronic ethanol consumption inhibits glucokinase transcriptional activity by Atf3 and triggers metabolic syndrome in vivo. J Biol Chem 2014; 289:27065-27079. [PMID: 25074928 PMCID: PMC4175344 DOI: 10.1074/jbc.m114.585653] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Chronic ethanol consumption induces pancreatic β-cell dysfunction through glucokinase (Gck) nitration and down-regulation, leading to impaired glucose tolerance and insulin resistance, but the underlying mechanism remains largely unknown. Here, we demonstrate that Gck gene expression and promoter activity in pancreatic β-cells were suppressed by chronic ethanol exposure in vivo and in vitro, whereas expression of activating transcription factor 3 (Atf3) and its binding to the putative Atf/Creb site (from −287 to −158 bp) on the Gck promoter were up-regulated. Furthermore, in vitro ethanol-induced Atf3 inhibited the positive effect of Pdx-1 on Gck transcriptional regulation, enhanced recruitment of Hdac1/2 and histone H3 deacetylation, and subsequently augmented the interaction of Hdac1/Pdx-1 on the Gck promoter, which were diminished by Atf3 siRNA. In vivo Atf3-silencing reversed ethanol-mediated Gck down-regulation and β-cell dysfunction, followed by the amelioration of impaired glucose tolerance and insulin resistance. Together, we identified that ethanol-induced Atf3 fosters β-cell dysfunction via Gck down-regulation and that its loss ameliorates metabolic syndrome and could be a potential therapeutic target in treating type 2 diabetes. The Atf3 gene is associated with the induction of type 2 diabetes and alcohol consumption-induced metabolic impairment and thus may be the major negative regulator for glucose homeostasis.
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Affiliation(s)
- Ji Yeon Kim
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Joo-Yeon Hwang
- Division of Structural and Functional Genomics, Center for Genomic Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Dae Yeon Lee
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea; Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | - Eun Hyun Song
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Keon Jae Park
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea; Division of Cardiology, Department of Internal Medicine, Chungbuk National University School of Medicine, Cheongju 361-763, Korea, and
| | - Gyu Hee Kim
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Eun Ae Jeong
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Yoo Jeong Lee
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Min Jin Go
- Division of Structural and Functional Genomics, Center for Genomic Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Dae Jin Kim
- Departments of Psychiatry and College of Medicine, Catholic University, Bucheon 420-743, Korea
| | - Seong Su Lee
- Departments of Endocrinology, College of Medicine, Catholic University, Bucheon 420-743, Korea
| | - Bong-Jo Kim
- Division of Structural and Functional Genomics, Center for Genomic Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Jihyun Song
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Gu Seob Roh
- Department of Anatomy and Neurobiology, Institute of Health Sciences, Gyeongsang National University, Jinju, Gyeongnam 660-751, Korea
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland 20892
| | - Won-Ho Kim
- Division of Metabolic Disease, Center for Biomedical Science, National Institutes of Health, Osong-eup, Cheongwon-gun, Chungbuk 363-951, Korea.
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22
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Avolio F, Pfeifer A, Courtney M, Gjernes E, Ben-Othman N, Vieira A, Druelle N, Faurite B, Collombat P. From pancreas morphogenesis to β-cell regeneration. Curr Top Dev Biol 2014; 106:217-38. [PMID: 24290351 DOI: 10.1016/b978-0-12-416021-7.00006-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Type 1 diabetes is a metabolic disease resulting in the selective loss of pancreatic insulin-producing β-cells and affecting millions of people worldwide. The side effects of diabetes are varied and include cardiovascular, neuropathologic, and kidney diseases. Despite the most recent advances in diabetes care, patients suffering from type 1 diabetes still display a shortened life expectancy compared to their healthy counterparts. In an effort to improve β-cell-replacement therapies, numerous approaches are currently being pursued, most of these aiming at finding ways to differentiate stem/progenitor cells into β-like cells by mimicking embryonic development. Unfortunately, these efforts have hitherto not allowed the generation of fully functional β-cells. This chapter summarizes recent findings, allowing a better insight into the molecular mechanisms underlying the genesis of β-cells during the course of pancreatic morphogenesis. Furthermore, a focus is made on new research avenues concerning the conversion of pre-existing pancreatic cells into β-like cells, such approaches holding great promise for the development of type 1 diabetes therapies.
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Affiliation(s)
- Fabio Avolio
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, Nice, France; Inserm, iBV, U1091, Nice, France; CNRS, iBV, UMR 7277, Nice, France
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23
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Van Pham P, Thi-My Nguyen P, Thai-Quynh Nguyen A, Minh Pham V, Nguyen-Tu Bui A, Thi-Tung Dang L, Gia Nguyen K, Kim Phan N. Improved differentiation of umbilical cord blood-derived mesenchymal stem cells into insulin-producing cells by PDX-1 mRNA transfection. Differentiation 2014; 87:200-8. [DOI: 10.1016/j.diff.2014.08.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 08/04/2014] [Accepted: 08/18/2014] [Indexed: 02/08/2023]
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24
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Niki Boroujeni Z, Aleyasin A. Human umbilical cord-derived mesenchymal stem cells can secrete insulinin vitroandin vivo. Biotechnol Appl Biochem 2014; 61:82-92. [DOI: 10.1002/bab.1127] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2013] [Accepted: 05/17/2013] [Indexed: 01/01/2023]
Affiliation(s)
| | - Ahmad Aleyasin
- National Institute of Genetic Engineering and Biotechnology; Tehran Iran
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25
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Aziz MTA, El-Asmar MF, Rezq AM, Wassef MAA, Fouad H, Roshdy NK, Ahmed HH, Rashed LA, Sabry D, Taha FM, Hassouna A. Effects of a novel curcumin derivative on insulin synthesis and secretion in streptozotocin-treated rat pancreatic islets in vitro. Chin Med 2014; 9:3. [PMID: 24422903 PMCID: PMC3896850 DOI: 10.1186/1749-8546-9-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 01/13/2014] [Indexed: 12/29/2022] Open
Abstract
Background Hyperglycemia induces activation of the c-Jun N-terminal kinase (JNK) pathway, which suppresses insulin gene expression and reduces DNA binding of pancreatic and duodenal homeobox factor (PDX)-1. This study aims to investigate the effects of a novel curcumin derivative (NCD) on JNK signaling pathway on insulin synthesis and secretion in streptozotocin (STZ)-treated rat pancreatic islets in vitro. Methods Isolated rat pancreatic islets were divided into five groups: untreated control group; group treated with NCD (10 μM); group exposed to STZ (5 mM); group treated with NCD (10 μM) and then exposed to STZ (5 mM); and group exposed to STZ (5 mM) and then treated with NCD (10 μM). The pancreatic islets from all groups were used for DNA fragmentation assays and quantitative assessments of the JNK, Pdx1, glucose transporter-2 (GLUT2), heme oxygenase (HO)-1, transcription factor 7-like 2 (TCF7L2), and glucagon-like peptide (GLP)-1 gene expression levels. The intracellular calcium, zinc, and the phosphorylated and total JNK protein levels were assessed. The insulin (secreted/total) and C-peptide levels were examined in islet culture medium. Results NCD protected pancreatic islets against STZ-induced DNA damage, improved total insulin (P = 0.001), secreted insulin (P = 0.001), and C-peptide levels (P = 0.001), normalized mRNA expressions of insulin, Pdx1, and GLUT2 (P = 0.0001), and significantly elevated calcium and zinc levels (P = 0.0001). All effects were significant when islets were treated with NCD before STZ (P = 0.05). JNK gene overexpression and JNK protein levels induced by STZ were significantly inhibited after NCD treatment of islets ( P = 0.0001). NCD-treated islets showed significantly elevated gene expressions of HO-1, TCF7L2, and GLP-1 (P = 0.0001), and these upregulated gene expressions were more significantly elevated with NCD treatment before STZ than after STZ (P = 0.05). Conclusions NCD improved insulin synthesis and secretion in vitro in isolated pancreatic islets treated with STZ through inhibition of the JNK pathway, up-regulation of the gene expressions of HO-1, TCF7L2, and GLP-1 and enhancing effects on calcium and zinc levels.
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Affiliation(s)
| | | | | | | | - Hanan Fouad
- Medical Biochemistry Department, Faculty of Medicine, Cairo University, POB 11562, Cairo, Egypt.
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Glucose regulates protein kinase CK2 in pancreatic β-cells and its interaction with PDX-1. Int J Biochem Cell Biol 2013; 45:2786-95. [DOI: 10.1016/j.biocel.2013.10.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 09/19/2013] [Accepted: 10/01/2013] [Indexed: 12/13/2022]
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Lee J, Kim SC, Kim SJ, Lee H, Jung EJ, Jung SH, Han DJ. Differentiation of human adipose tissue-derived stem cells into aggregates of insulin-producing cells through the overexpression of pancreatic and duodenal homeobox gene-1. Cell Transplant 2012; 22:1053-60. [PMID: 23031216 DOI: 10.3727/096368912x657215] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The pancreatic and duodenal homeobox gene 1 (Pdx-1) plays a key role in normal pancreas development and is required for maintaining the normal function of islets. In this study, we examined whether human adipose tissue-derived stem cells (hASCs) could differentiate into insulin-producing cells by exogenously expressed Pdx-1. hASCs were infected with recombinant adenovirus encoding the mouse Pdx-1 gene and differentiated under high-glucose conditions. Insulin transcript levels and the expression of key transcription factors required for pancreatic development including FoxA2, Nkx2.2, and NeuroD were significantly increased by exogenous Pdx-1 overexpression. The expression of Nkx6.1 was found only in Pdx-1-induced hASCs. In addition to transcripts for transcription factors involved in pancreatic development, transcripts for the GLP-1 receptor, glucokinase, and glucose transporter, which are required for maintaining the function of pancreatic β-cells, were observed only in Pdx-1-induced hASCs. Pdx-1-induced hASCs exhibited insulin secretion in response to glucose challenge in vitro. When Pdx-1-induced hASCs were transplanted into streptozotocin (STZ)-induced diabetic mice, they reduced blood glucose levels, although they did not restore normoglycemia. These results demonstrate that the expression of exogenous Pdx-1 is sufficient to induce pancreatic differentiation in vitro but does not induce the fully functional, mature insulin-producing cells that are required for restoring normoglycemia in vivo.
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Affiliation(s)
- Jiyeon Lee
- Laboratory of Stem Cell Biology and Cell Therapy, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea
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Development of novel cell lines of diabetic dysfunction model fit for cell-based screening tests of medicinal materials. Cytotechnology 2012; 65:105-18. [PMID: 22777586 DOI: 10.1007/s10616-012-9466-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 05/14/2012] [Indexed: 10/28/2022] Open
Abstract
Pdx-1 and Irs-1, genes highly associated with diabetes onset, were knocked down in mouse embryonic stem (ES) cells in order to develop cell line models for diabetes. ES cells with different gene knockdown levels were induced to differentiate to the stage of insulin production. Among the cell lines that differentiated, we identified two in which the levels of expression of both genes were 20-40 % of that of control cells. These cell lines showed appreciable deficiencies in three characteristic malfunctions associated with diabetes, namely, insulin production, insulin reception signaling, and glucose-stimulated insulin secretion. These dysfunctions were consistent with results reported elsewhere from in vivo and in vitro studies. Both cell lines did not show any abnormal morphology such as size, shape, color, and surface roughness. No abnormal expression profiles for 17 genes relevant to diabetes were observed. Therefore, these cell lines fulfilled the criteria for a validated cell model for diabetes. The model cell lines developed here are promising biomaterials for cell-based screening tests of new medicines that may be effective in treating diabetes.
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Chen C, Leavitt T, Sibley E. Intestinal Pdx1 mediates nutrient metabolism gene networks and maternal expression is essential for perinatal growth in mice. Biochem Biophys Res Commun 2012; 424:549-53. [PMID: 22771330 DOI: 10.1016/j.bbrc.2012.06.153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 06/28/2012] [Indexed: 11/17/2022]
Abstract
The homeodomain transcription factor Pdx1 is essential for pancreas formation and functions in pancreatic islets cells to regulate genes involved in maintenance of glucose homeostasis. In order to investigate a role for Pdx1 in intestinal cells, we analyzed the functions and networks associated with genes differentially expressed by Pdx1 overexpression in human Caco-2 cells. In agreement with previous results for intestine isolated from mice with Pdx1 inactivation, functional analysis of genes differentially expressed with Pdx1 overexpression revealed functions significantly associated with nutrient metabolism. Similarly, network analysis examining the interactions among the differentially expressed genes revealed gene networks involved in lipid metabolism. Consistent with defects in maternal nutrient metabolism, mouse pups born to dams with intestine-specific Pdx1 inactivation are underweight and fail to thrive in the neonatal period compared to pups born to control dams. We conclude that Pdx1 mediates lipid metabolism gene networks in intestinal cells and that maternal expression is essential for perinatal growth in mice.
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Affiliation(s)
- Chin Chen
- Division of Pediatric Gastroenterology, Stanford University School of Medicine, Stanford, CA 94305-5208, USA
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Chen C, Fang R, Chou LC, Lowe AW, Sibley E. PDX1 regulation of FABP1 and novel target genes in human intestinal epithelial Caco-2 cells. Biochem Biophys Res Commun 2012; 423:183-7. [PMID: 22640736 DOI: 10.1016/j.bbrc.2012.05.113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 05/18/2012] [Indexed: 10/28/2022]
Abstract
The transcription factor pancreatic and duodenal homeobox 1 (PDX1) plays an essential role in pancreatic development and in maintaining proper islet function via target gene regulation. Few intestinal PDX1 targets, however, have been described. We sought to define novel PDX1-regulated intestinal genes. Caco-2 human intestinal epithelial cells were engineered to overexpress PDX1 and gene expression profiles relative to control cells were assessed. Expression of 80 genes significantly increased while that of 49 genes significantly decreased more than 4-fold following PDX1 overexpression in differentiated Caco-2 cells. Analysis of the differentially regulated genes with known functional annotations revealed genes encoding transcription factors, growth factors, kinases, digestive glycosidases, nutrient transporters, nutrient binding proteins, and structural components. The gene for fatty acid binding protein 1, liver, FABP1, is repressed by PDX1 in Caco-2 cells. PDX1 overexpression in Caco-2 cells also results in repression of promoter activity driven by the 0.6kb FABP1 promoter. PDX1 regulation of promoter activity is consistent with the decrease in FABP1 RNA abundance resulting from PDX1 overexpression and identifies FABP1 as a candidate PDX1 target. PDX1 repression of FABP1, LCT, and SI suggests a role for PDX1 in patterning anterior intestinal development.
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Affiliation(s)
- Chin Chen
- Division of Pediatric Gastroenterology, Stanford University School of Medicine, Stanford, CA 94305-5208, United States
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Frogne T, Sylvestersen KB, Kubicek S, Nielsen ML, Hecksher-Sørensen J. Pdx1 is post-translationally modified in vivo and serine 61 is the principal site of phosphorylation. PLoS One 2012; 7:e35233. [PMID: 22509401 PMCID: PMC3324462 DOI: 10.1371/journal.pone.0035233] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 03/14/2012] [Indexed: 11/19/2022] Open
Abstract
Maintaining sufficient levels of Pdx1 activity is a prerequisite for proper regulation of blood glucose homeostasis and beta cell function. Mice that are haploinsufficient for Pdx1 display impaired glucose tolerance and lack the ability to increase beta cell mass in response to decreased insulin signaling. Several studies have shown that post-translational modifications are regulating Pdx1 activity through intracellular localization and binding to co-factors. Understanding the signaling cues converging on Pdx1 and modulating its activity is therefore an attractive approach in diabetes treatment. We employed a novel technique called Nanofluidic Proteomic Immunoassay to characterize the post-translational profile of Pdx1. Following isoelectric focusing in nano-capillaries, this technology relies on a pan specific antibody for detection and it therefore allows the relative abundance of differently charged protein species to be examined simultaneously. In all eukaryotic cells tested we find that the Pdx1 protein separates into four distinct peaks whereas Pdx1 protein from bacteria only produces one peak. Of the four peaks in eukaryotic cells we correlate one of them to a phosphorylation Using alanine scanning and mass spectrometry we map this phosphorylation to serine 61 in both Min6 cells and in exogenous Pdx1 over-expressed in HEK293 cells. A single phosphorylation is also present in cultured islets but it remains unaffected by changes in glucose levels. It is present during embryogenesis but is not required for pancreas development.
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Affiliation(s)
- Thomas Frogne
- Department of Beta-cell Regeneration, Hagedorn Research Institute, Gentofte, Denmark
| | | | - Stefan Kubicek
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | | | - Jacob Hecksher-Sørensen
- Department of Beta-cell Regeneration, Hagedorn Research Institute, Gentofte, Denmark
- * E-mail:
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Chen C, Sibley E. Expression profiling identifies novel gene targets and functions for Pdx1 in the duodenum of mature mice. Am J Physiol Gastrointest Liver Physiol 2012; 302:G407-19. [PMID: 22135308 PMCID: PMC3287393 DOI: 10.1152/ajpgi.00314.2011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 11/28/2011] [Indexed: 01/31/2023]
Abstract
Transcription factor pancreatic and duodenal homeobox 1 (Pdx1) plays an essential role in the pancreas to regulate its development and maintain proper islet function. However, the functions of Pdx1 in mature small intestine are less known. We aimed to investigate the intestinal role of Pdx1 by profiling the expression of genes differentially regulated in response to inactivation of Pdx1 specifically in the intestinal epithelium. Pdx1 was conditionally inactivated in the intestinal epithelium of Pdx1(flox/flox);VilCre mice. Total RNA was isolated from the first 5 cm of the small intestine from mature Pdx1(flox/flox);VilCre and littermate control mice. Microarray analysis identified 86 probe sets representing 68 genes significantly upregulated or downregulated 1.5-fold or greater in Pdx(flox/flox);VilCre mice maintained under standard conditions. Ingenuity Pathway Analysis revealed that functions of the differentially expressed genes are significantly associated with metabolism of nutrients including lipids and iron. Network analysis examining the interactions among the differentially expressed genes further supports the notion that Pdx1 may modulate metabolism of lipids and iron from mature intestinal epithelium. Following forced oil feeding, Pdx1(flox/flox);VilCre mice showed diminished lipid staining in the duodenal epithelium and decreased serum triglyceride levels, indicating reduced lipid absorption compared with control duodenal epithelium. Blood samples from Pdx1(flox/flox);VilCre mice have significantly lower mean values for mean corpuscular volume and mean corpuscular hemoglobin, consistent with iron deficiency. The absence of nonheme iron in the villous epithelium and lamina propria of Pdx1(flox/flox);VilCre duodenum indicates that the duodenal epithelium lacking Pdx1 may have defects in importing iron through enterocytes, resulting in iron deficiency in Pdx1(flox/flox);VilCre mice.
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Affiliation(s)
- Chin Chen
- Dept. of Pediatrics, Stanford Univ. School of Medicine, Stanford, CA 94305-5208, USA.
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Abstract
Classic experiments such as somatic cell nuclear transfer into oocytes and cell fusion demonstrated that differentiated cells are not irreversibly committed to their fate. More recent work has built on these conclusions and discovered defined factors that directly induce one specific cell type from another, which may be as distantly related as cells from different germ layers. This suggests the possibility that any specific cell type may be directly converted into any other if the appropriate reprogramming factors are known. Direct lineage conversion could provide important new sources of human cells for modeling disease processes or for cellular-replacement therapies. For future applications, it will be critical to carefully determine the fidelity of reprogramming and to develop methods for robustly and efficiently generating human cell types of interest.
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Affiliation(s)
- Thomas Vierbuchen
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
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Li YG, Ji DF, Zhong S, Lv ZQ, Lin TB, Chen S, Hu GY. Hybrid of 1-deoxynojirimycin and polysaccharide from mulberry leaves treat diabetes mellitus by activating PDX-1/insulin-1 signaling pathway and regulating the expression of glucokinase, phosphoenolpyruvate carboxykinase and glucose-6-phosphatase in alloxan-induced diabetic mice. JOURNAL OF ETHNOPHARMACOLOGY 2011; 134:961-970. [PMID: 21333726 DOI: 10.1016/j.jep.2011.02.009] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2010] [Revised: 11/29/2010] [Accepted: 02/11/2011] [Indexed: 05/30/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE 1-Deoxynojirimycin (DNJ) discovered from mulberry trees has been reported to be a potent inhibitor of intestinal α-glycosidases (sucrase, maltase, glucoamylase), and many polysaccharides were useful in protecting against alloxan-induced pancreatic islets damage through their scavenging ability. This study was aimed to evaluate the therapeutic effect and potential mechanism(s) of the hybrid of DNJ and polysaccharide (HDP) from mulberry leaves on alloxan-induced diabetic mice. MATERIALS AND METHODS Daily oral treatment with HDP (150 mg/kg body weight) to diabetic mice for 12 weeks, body weight and blood glucose were determined every week, oral glucose tolerance test was performed after 4 and 8 weeks, biochemical values were measured using assay kits and gene expressions were investigated by RT-PCR. RESULTS A significant decline in blood glucose, glycosylated hemoglobin, triglyceride, aspartate transaminase and alanine transaminase levels and an evident increase in body weight, plasma insulin level and high density lipoprotein were observed in HDP treated diabetic mice. The polysaccharide (P1) showed a significant scavenging hydroxyl radicals and superoxide anion radical effects in vitro, which indicated that P1 could protect alloxan-induced pancreatic islets from damage by scavenging the free radicals and repaired the destroyed pancreatic β-cells. Pharmacokinetics assay showed that DNJ could be absorbed from the gastrointestinal mucosa and diffused rapidly into the liver, resulted in postprandial blood glucose decrease and alleviated the toxicity caused by sustained supra-physiological glucose to pancreatic β-cells. RT-PCR results indicated that HDP could modulate the hepatic glucose metabolism and gluconeogenesis by up/down-regulating the expression of rate-limiting enzymes (glucokinase, phosphoenolpyruvate carboxykinase and glucose-6-phosphatase) in liver and up-regulating the pancreatic and duodenal homeobox factor-1 (PDX-1), insulin-1 and insulin-2 expressions in pancreas. CONCLUSION These findings suggested that HDP has complimentary potency to develop an antihyperglycemic agent for treatment of diabetes mellitus.
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Affiliation(s)
- You-Gui Li
- Sericultural Research Institute, Zhejiang Academy of Agricultural Science, No. 198 Shiqiao Road, Hangzhou 310021, China
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miRNAs control insulin content in pancreatic β-cells via downregulation of transcriptional repressors. EMBO J 2011; 30:835-45. [PMID: 21285947 DOI: 10.1038/emboj.2010.361] [Citation(s) in RCA: 224] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Accepted: 12/16/2010] [Indexed: 02/08/2023] Open
Abstract
MicroRNAs (miRNAs) were shown to be important for pancreas development, yet their roles in differentiated β-cells remain unclear. Here, we show that miRNA inactivation in β-cells of adult mice results in a striking diabetic phenotype. While islet architecture is intact and differentiation markers are maintained, Dicer1-deficient β-cells show a dramatic decrease in insulin content and insulin mRNA. As a consequence of the change in insulin content, the animals become diabetic. We provide evidence for involvement of a set of miRNAs in regulating insulin synthesis. The specific knockdown of miR-24, miR-26, miR-182 or miR-148 in cultured β-cells or in isolated primary islets downregulates insulin promoter activity and insulin mRNA levels. Further, miRNA-dependent regulation of insulin expression is associated with upregulation of transcriptional repressors, including Bhlhe22 and Sox6. Thus, miRNAs in the adult pancreas act in a new network that reinforces insulin expression by reducing the expression of insulin transcriptional repressors.
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Ait-Lounis A, Bonal C, Seguín-Estévez Q, Schmid CD, Bucher P, Herrera PL, Durand B, Meda P, Reith W. The transcription factor Rfx3 regulates beta-cell differentiation, function, and glucokinase expression. Diabetes 2010; 59:1674-85. [PMID: 20413507 PMCID: PMC2889767 DOI: 10.2337/db09-0986] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Pancreatic islets of perinatal mice lacking the transcription factor Rfx3 exhibit a marked reduction in insulin-producing beta-cells. The objective of this work was to unravel the cellular and molecular mechanisms underlying this deficiency. RESEARCH DESIGN AND METHODS Immunofluorescence studies and quantitative RT-PCR experiments were used to study the emergence of insulin-positive cells, the expression of transcription factors implicated in the differentiation of beta-cells from endocrine progenitors, and the expression of mature beta-cell markers during development in Rfx3(-/-) and pancreas-specific Rfx3-knockout mice. RNA interference experiments were performed to document the consequences of downregulating Rfx3 expression in Min6 beta-cells. Quantitative chromatin immunoprecipitation (ChIP), ChIP sequencing, and bandshift experiments were used to identify Rfx3 target genes. RESULTS Reduced development of insulin-positive cells in Rfx3(-/-) mice was not due to deficiencies in endocrine progenitors or beta-lineage specification, but reflected the accumulation of insulin-positive beta-cell precursors and defective beta-cells exhibiting reduced insulin, Glut-2, and Gck expression. Similar incompletely differentiated beta-cells developed in pancreas-specific Rfx3-deficient embryos. Defective beta-cells lacking Glut-2 and Gck expression dominate in Rfx3-deficent adults, leading to glucose intolerance. Attenuated Glut-2 and glucokinase expression, and impaired glucose-stimulated insulin secretion, were also induced by RNA interference-mediated inhibition of Rfx3 expression in Min6 cells. Finally, Rfx3 was found to bind in Min6 cells and human islets to two well-known regulatory sequences, Pal-1 and Pal-2, in the neuroendocrine promoter of the glucokinase gene. CONCLUSIONS Our results show that Rfx3 is required for the differentiation and function of mature beta-cells and regulates the beta-cell promoter of the glucokinase gene.
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Affiliation(s)
- Aouatef Ait-Lounis
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Centre Médical Universitaire (CMU), Geneva, Switzerland
| | - Claire Bonal
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Queralt Seguín-Estévez
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Centre Médical Universitaire (CMU), Geneva, Switzerland
| | - Christoph D. Schmid
- Swiss Institute of Bioinformatics Ecole Polytechnique Fédeŕale de Lausanne, Institut Suisse de Recherche Expérimentale sur le Cancer, Lausanne, Switzerland
| | - Philipp Bucher
- Swiss Institute of Bioinformatics Ecole Polytechnique Fédeŕale de Lausanne, Institut Suisse de Recherche Expérimentale sur le Cancer, Lausanne, Switzerland
| | - Pedro L. Herrera
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Bénédicte Durand
- University of Lyon, Lyon, France, and Centre National de la Recherche Sciéntifique, Unité Mixte de Recherche 5534, Centre de Génétique Moléculaire et Cellulaire, Villeurbanne, France
| | - Paolo Meda
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Walter Reith
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Centre Médical Universitaire (CMU), Geneva, Switzerland
- Corresponding author: Walter Reith,
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Transcriptional regulation of glucose sensors in pancreatic β-cells and liver: an update. SENSORS 2010; 10:5031-53. [PMID: 22399922 PMCID: PMC3292162 DOI: 10.3390/s100505031] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Revised: 05/07/2010] [Accepted: 05/13/2010] [Indexed: 01/17/2023]
Abstract
Pancreatic β-cells and the liver play a key role in glucose homeostasis. After a meal or in a state of hyperglycemia, glucose is transported into the β-cells or hepatocytes where it is metabolized. In the β-cells, glucose is metabolized to increase the ATP:ADP ratio, resulting in the secretion of insulin stored in the vesicle. In the hepatocytes, glucose is metabolized to CO(2), fatty acids or stored as glycogen. In these cells, solute carrier family 2 (SLC2A2) and glucokinase play a key role in sensing and uptaking glucose. Dysfunction of these proteins results in the hyperglycemia which is one of the characteristics of type 2 diabetes mellitus (T2DM). Thus, studies on the molecular mechanisms of their transcriptional regulations are important in understanding pathogenesis and combating T2DM. In this paper, we will review a recent update on the progress of gene regulation of glucose sensors in the liver and β-cells.
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Humphrey RK, Yu SM, Flores LE, Jhala US. Glucose regulates steady-state levels of PDX1 via the reciprocal actions of GSK3 and AKT kinases. J Biol Chem 2010; 285:3406-16. [PMID: 19833727 PMCID: PMC2823452 DOI: 10.1074/jbc.m109.006734] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Revised: 10/09/2009] [Indexed: 12/31/2022] Open
Abstract
The pancreatic beta cell is sensitive to even small changes in PDX1 protein levels; consequently, Pdx1 haploinsufficiency can inhibit beta cell growth and decrease insulin biosynthesis and gene expression, leading to compromised glucose-stimulated insulin secretion. Using metabolic labeling of primary islets and a cultured beta cell line, we show that glucose levels modulate PDX1 protein phosphorylation at a novel C-terminal GSK3 consensus that maps to serines 268 and 272. A decrease in glucose levels triggers increased turnover of the PDX1 protein in a GSK3-dependent manner, such that PDX1 phosphomutants are refractory to the destabilizing effect of low glucose. Glucose-stimulated activation of AKT and inhibition of GSK3 decrease PDX1 phosphorylation and delay degradation. Furthermore, direct pharmacologic inhibition of AKT destabilizes, and inhibition of GSK3 increases PDX1 protein stability. These studies define a novel functional role for the PDX1 C terminus in mediating the effects of glucose and demonstrate that glucose modulates PDX1 stability via the AKT-GSK3 axis.
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Affiliation(s)
- Rohan K. Humphrey
- From the Department of Pediatrics, University of California San Diego, La Jolla, California 92037
| | - Shu-Mei Yu
- From the Department of Pediatrics, University of California San Diego, La Jolla, California 92037
| | - Luis E. Flores
- From the Department of Pediatrics, University of California San Diego, La Jolla, California 92037
| | - Ulupi S. Jhala
- From the Department of Pediatrics, University of California San Diego, La Jolla, California 92037
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Chen C, Fang R, Davis C, Maravelias C, Sibley E. Pdx1 inactivation restricted to the intestinal epithelium in mice alters duodenal gene expression in enterocytes and enteroendocrine cells. Am J Physiol Gastrointest Liver Physiol 2009; 297:G1126-37. [PMID: 19808654 PMCID: PMC2850094 DOI: 10.1152/ajpgi.90586.2008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Null mutant mice lacking the transcription factor pancreatic and duodenal homeobox 1 (Pdx1) are apancreatic and survive only a few days after birth. The role of Pdx1 in regulating intestinal gene expression has therefore yet to be determined in viable mice with normal pancreatic development. We hypothesized that conditional inactivation of Pdx1 restricted to the intestinal epithelium would alter intestinal gene expression and cell differentiation. Pdx1(flox/flox);VilCre mice with intestine-specific Pdx1 inactivation were generated by crossing a transgenic mouse strain expressing Cre recombinase, driven by a mouse villin 1 gene promoter fragment, with a mutant mouse strain homozygous for loxP site-flanked Pdx1. Pdx1 protein is undetectable in all epithelial cells in the intestinal epithelium of Pdx1(flox/flox);VilCre mice. Goblet cell number and mRNA abundance for mucin 3 and mucin 13 genes in the proximal small intestine are comparable between Pdx1(flox/flox);VilCre and control mice. Similarly, Paneth cell number and expression of Paneth cell-related genes Defa1, Defcr-rs1, and Mmp7 in the proximal small intestine remain statistically unchanged by Pdx1 inactivation. Although the number of enteroendocrine cells expressing chromogranin A/B, gastric inhibitory polypeptide (Gip), or somatostatin (Sst) is unaffected in the Pdx1(flox/flox);VilCre mice, mRNA abundance for Gip and Sst is significantly reduced in the proximal small intestine. Conditional Pdx1 inactivation attenuates intestinal alkaline phosphatase (IAP) activity in the duodenal epithelium, consistent with an average 91% decrease in expression of the mouse enterocyte IAP gene, alkaline phosphatase 3 (a novel Pdx1 target candidate), in the proximal small intestine following Pdx1 inactivation. We conclude that Pdx1 is necessary for patterning appropriate gene expression in enterocytes and enteroendocrine cells of the proximal small intestine.
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Affiliation(s)
- Chin Chen
- Stanford Univ. School of Medicine, CA 94305-5208, USA.
| | - Rixun Fang
- 1Division of Pediatric Gastroenterology and
| | - Corrine Davis
- 2Department of Comparative Medicine, Stanford University School of Medicine, Stanford, California
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Naujok O, Francini F, Picton S, Bailey CJ, Lenzen S, Jörns A. Changes in gene expression and morphology of mouse embryonic stem cells on differentiation into insulin-producing cells in vitro and in vivo. Diabetes Metab Res Rev 2009; 25:464-76. [PMID: 19425055 DOI: 10.1002/dmrr.965] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Embryonic stem (ES) cells have the potential to produce unlimited numbers of surrogate insulin-producing cells for cell replacement therapy of type 1 diabetes mellitus. The impact of the in vivo environment on mouse ES cell differentiation towards insulin-producing cells was analysed morphologically after implantation. METHODS ES cells differentiated in vitro into insulin-producing cells according to the Lumelsky protocol or a new four-stage differentiation protocol were analysed morphologically before and after implantation for gene expression by in situ reverse transcription polymerase chain reaction and protein expression by immunohistochemistry and ultrastructural analysis. RESULTS In comparison with nestin positive ES cells developed according to the reference protocol, the number of ES cells differentiated with the four-stage protocol increased under in vivo conditions upon morphological analysis. The cells exhibited, in comparison to the in vitro situation, increased gene and protein expression of Pdx1, insulin, islet amyloid polypeptide (IAPP), the GLUT2 glucose transporter and glucokinase, which are functional markers for glucose-induced insulin secretion of pancreatic beta cells. Renal sub-capsular implantation of ES cells with a higher degree of differentiation achieved by in vitro differentiation with a four-stage protocol enabled further significant maturation for the beta-cell-specific markers, insulin and the co-stored IAPP as well as the glucose recognition structures. In contrast, further in vivo differentiation was not achieved with cells differentiated in vitro by the reference protocol. CONCLUSIONS A sufficient degree of in vitro differentiation is an essential prerequisite for further substantial maturation in a beta-cell-specific way in vivo, supported by cell-cell contacts and vascularisation.
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Affiliation(s)
- Ortwin Naujok
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
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41
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Szabat M, Luciani DS, Piret JM, Johnson JD. Maturation of adult beta-cells revealed using a Pdx1/insulin dual-reporter lentivirus. Endocrinology 2009; 150:1627-35. [PMID: 19095744 DOI: 10.1210/en.2008-1224] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The enigmatic process of beta-cell maturation has significant implications for diabetes pathogenesis, and potential diabetes therapies. This study examined the dynamics and heterogeneity of insulin and pancreatic duodenal homeobox (Pdx)-1 gene expression in adult beta-cells. Insulin and Pdx1 expression were monitored in human and mouse islet cells and MIN6 cells using a Pdx1-monomeric red fluorescent protein/insulin-enhanced green fluorescent protein dual-reporter lentivirus. The majority of fluorescent cells were highly positive for both Pdx1 and insulin. Cells expressing Pdx1 but little or no insulin (Pdx1(+)/Ins(low)) comprised 15-25% of the total population. Time-lapse imaging demonstrated that Pdx1(+)/Ins(low) primary beta-cells and MIN6 cells could convert to Pdx1(+)/Ins(+) cells without cell division. Genes involved in the mature beta-cell phenotype (Glut2, MafA) were expressed at higher levels in Pdx1(+)/Ins(+) cells relative to Pdx1(+)/Ins(low) cells. Conversely, genes implicated in early beta-cell development (MafB, Nkx2.2) were enriched in Pdx1(+)/Ins(low) cells. Sorted Pdx1(+)/Ins(low) MIN6 cells had a higher replication rate and secreted less insulin relative to double-positive cells. Long-term phenotype tracking of Pdx1(+)/Ins(low) cells showed two groups, one that matured into Pdx1(+)/Ins(+) cells and one that remained immature. These results demonstrate that adult beta-cells pass through distinct maturation states, which is consistent with previously observed heterogeneity in insulin and Pdx1 expression in adult beta-cells. At a given time, a proportion of adult beta-cells share similar characteristics to functionally immature embryonic beta-cell progenitors. The maturation of adult beta-cells recapitulates development in that Pdx1 expression precedes the robust expression of insulin and other mature beta-cell genes. These results have implications for harnessing the maturation process for therapeutic purposes.
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Affiliation(s)
- Marta Szabat
- Michael Smith Laboratories, University of British Columbia, Vancouver, Canada
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Peroxisome proliferator-activated receptor gamma activation restores islet function in diabetic mice through reduction of endoplasmic reticulum stress and maintenance of euchromatin structure. Mol Cell Biol 2009; 29:2053-67. [PMID: 19237535 DOI: 10.1128/mcb.01179-08] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR-gamma) is an important target in diabetes therapy, but its direct role, if any, in the restoration of islet function has remained controversial. To identify potential molecular mechanisms of PPAR-gamma in the islet, we treated diabetic or glucose-intolerant mice with the PPAR-gamma agonist pioglitazone or with a control. Treated mice exhibited significantly improved glycemic control, corresponding to increased serum insulin and enhanced glucose-stimulated insulin release and Ca(2+) responses from isolated islets in vitro. This improved islet function was at least partially attributed to significant upregulation of the islet genes Irs1, SERCA, Ins1/2, and Glut2 in treated animals. The restoration of the Ins1/2 and Glut2 genes corresponded to a two- to threefold increase in the euchromatin marker histone H3 dimethyl-Lys4 at their respective promoters and was coincident with increased nuclear occupancy of the islet methyltransferase Set7/9. Analysis of diabetic islets in vitro suggested that these effects resulting from the presence of the PPAR-gamma agonist may be secondary to improvements in endoplasmic reticulum stress. Consistent with this possibility, incubation of thapsigargin-treated INS-1 beta cells with the PPAR-gamma agonist resulted in the reduction of endoplasmic reticulum stress and restoration of Pdx1 protein levels and Set7/9 nuclear occupancy. We conclude that PPAR-gamma agonists exert a direct effect in diabetic islets to reduce endoplasmic reticulum stress and enhance Pdx1 levels, leading to favorable alterations of the islet gene chromatin architecture.
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Abstract
The glucokinase (GCK) gene was one of the first candidate genes to be identified as a human “diabetes gene". Subsequently, important advances were made in understanding the impact of GCK in the regulation of glucose metabolism. Structure elucidation by crystallography provided insight into the kinetic properties of GCK. Protein interaction partners of GCK were discovered. Gene expression studies revealed new facets of the tissue distribution of GCK, including in the brain, and its regulation by insulin in the liver. Metabolic control analysis coupled to gene overexpression and knockout experiments highlighted the unique impact of GCK as a regulator of glucose metabolism. Human GCK mutants were studied biochemically to understand disease mechanisms. Drug development programs identified small molecule activators of GCK as potential antidiabetics. These advances are summarized here, with the aim of offering an integrated view of the role of GCK in the molecular physiology and medicine of glucose homeostasis.
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Affiliation(s)
- P B Iynedjian
- Department of Cell Physiolgy and Metabolism, University of Geneva School of Medicine, CMU 1 Rue Michel-Servet, 1211 Geneva 4, Switzerland.
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Miyatsuka T, Matsuoka TA, Kaneto H. Transcription factors as therapeutic targets for diabetes. Expert Opin Ther Targets 2009; 12:1431-42. [PMID: 18851698 DOI: 10.1517/14728222.12.11.1431] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Islet cell implantation and pancreas transplantation have been used as treatments for diabetes but are limited by the shortage of donors and the requirement for lifelong immunosuppression. As an alternative, the generation of surrogate insulin-producing cells has been an area of interest for many researchers. Understanding how pancreatic beta-cells are generated during pancreas development will provide information that can be applied to generating surrogate beta-cells. OBJECTIVE To outline the current knowledge of pancreas development and differentiation, with a focus on the regulatory network of pancreas-enriched transcription factors and their targets. METHODS A review of relevant literature. CONCLUSIONS Pancreatic and duodenal homeobox 1 (Pdx1), Neurogenin 3 (Ngn3), and musculoaponeurotic fibrosarcoma oncogene homolog A (MafA) have been shown to play essential roles in pancreas development and beta-cell differentiation, and gain-of-function approaches indicate the potency of these factors for inducing differentiation of non-beta-cells into insulin-producing cells, which could lead to a novel therapy to cure diabetes.
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Affiliation(s)
- Takeshi Miyatsuka
- Osaka University Graduate School of Medicine, Department of Internal Medicine and Therapeutics, 2-2 Yamadaoka, Suita 565-0871, Osaka, Japan
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Nakayama S, Arakawa M, Uchida T, Ogihara T, Kanno R, Ikeda F, Azuma K, Hirose T, Kawamori R, Fujitani Y, Watada H. Dose-dependent requirement of patched homologue 1 in mouse pancreatic beta cell mass. Diabetologia 2008; 51:1883-92. [PMID: 18654758 DOI: 10.1007/s00125-008-1080-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Accepted: 05/23/2008] [Indexed: 12/16/2022]
Abstract
AIMS/HYPOTHESIS Ectopic activation of hedgehog (HH) signalling in pancreas induces various abnormal morphogenetic events in the pancreas. This study analysed the dose-dependent requirement of patched homologue 1 (PTCH1), a negative regulator of HH signalling on pancreatic development. METHODS We used a recessive spontaneous mutant mouse denoted as mes which carries a mutated Ptch1 resulting in deletion of the most carboxy-terminal cytoplasmic domain of the PTCH1 protein. In this study, we analysed pancreatic morphology in Ptch1 ( +/+ ), Ptch1 ( +/mes ), Ptch1 (+/-), Ptch1 ( mes/me ) (s) and Ptch1 (-/mes ) mouse embryos, as well as the islet mass in adult Ptch1 (+/+), Ptch1 (+/mes ) and Ptch1 (+/-) mice. RESULTS Until embryonic day (E) 12.5, no obvious abnormality of pancreas was observed in any of the Ptch1 mutants. The levels of PDX1 and glucagon were also not evidently different among the mice genotypes studied. Thereafter, morphological abnormalities appeared in the Ptch1 mutant mice. The beta, alpha and exocrine cell masses decreased at E18.5 in parallel with increased HH signalling, with beta cell mass showing the highest sensitivity to HH signalling with a significant decrease even in Ptch1 (+/mes ) mice. Adult Ptch1 (+/-) mice also showed a significant decrease in beta cell mass compared with wild-type mice. CONCLUSIONS/INTERPRETATION Our findings indicate that the carboxy-terminal domain of Ptch1 is essential for pancreatic development. In addition, the loss of Ptch1 function decreases both the endocrine and exocrine cell mass in a dose-dependent manner, with beta cells particularly sensitive to changes in HH signalling.
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Affiliation(s)
- S Nakayama
- Department of Medicine, Metabolism and Endocrinology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
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Kaneto H, Miyatsuka T, Kawamori D, Yamamoto K, Kato K, Shiraiwa T, Katakami N, Yamasaki Y, Matsuhisa M, Matsuoka TA. PDX-1 and MafA play a crucial role in pancreatic beta-cell differentiation and maintenance of mature beta-cell function. Endocr J 2008; 55:235-52. [PMID: 17938503 DOI: 10.1507/endocrj.k07e-041] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Pancreatic and duodenal homeobox factor-1 (PDX-1) plays a crucial role in pancreas development, beta-cell differentiation, and maintenance of mature beta-cell function. PDX-1 expression is maintained in pancreatic precursor cells during pancreas development but becomes restricted to beta-cells in mature pancreas. In mature beta-cells, PDX-1 transactivates the insulin and other genes involved in glucose sensing and metabolism such as GLUT2 and glucokinase. MafA is a recently isolated beta-cell-specific transcription factor which functions as a potent activator of insulin gene transcription. Furthermore, these transcription factors play an important role in induction of insulin-producing cells in various non-beta-cells and thus could be therapeutic targets for diabetes. On the other hand, under diabetic conditions, expression and/or activities of PDX-1 and MafA in beta-cells are reduced, which leads to suppression of insulin biosynthesis and secretion. It is likely that alteration of such transcription factors explains, at least in part, the molecular mechanism for beta-cell glucose toxicity found in diabetes.
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Affiliation(s)
- Hideaki Kaneto
- Department of Internal Medicine and Therapeutics (A8), Osaka University Graduate School of Medicine, Osaka, Japan
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Abstract
It is well known that pancreatic and duodenal homeobox factor-1 (PDX-1) plays a pleiotropic role in the pancreas. In the developing pancreas, PDX-1 is involved in both pancreas formation and beta-cell differentiation. In mature beta-cells, PDX-1 transactivates insulin and other beta-cell-related genes such as GLUT2 and glucokinase. Furthermore, PDX-1 plays an important role in the induction of insulin-producing cells in various non-beta-cells and is thereby a possible therapeutic target for diabetes. On the other hand, under diabetic conditions, expression and/or activity of PDX-1 in beta-cells is reduced, which leads to suppression of insulin biosynthesis and secretion. It is likely that PDX-1 inactivation explains, at least in part, the molecular mechanism for beta-cell glucose toxicity found in diabetes.
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Affiliation(s)
- Hideaki Kaneto
- Department of Internal Medicine and Therapeutics (A8), Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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48
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Won KC, Yoon JS. Glucose Toxicity and Pancreatic Beta Cell Dysfunction in Type 2 Diabetes. KOREAN DIABETES JOURNAL 2008. [DOI: 10.4093/kdj.2008.32.3.175] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Kyu Chang Won
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| | - Ji Sung Yoon
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
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Shiraiwa T, Kaneto H, Miyatsuka T, Kato K, Yamamoto K, Kawashima A, Kajimoto Y, Matsuoka TA, Matsuhisa M, Yamasaki Y, Fujitani Y. Establishment of a non-invasive mouse reporter model for monitoring in vivo pdx-1 promoter activity. Biochem Biophys Res Commun 2007; 361:739-44. [PMID: 17678877 DOI: 10.1016/j.bbrc.2007.07.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2007] [Accepted: 07/06/2007] [Indexed: 11/17/2022]
Abstract
It is well known that pancreatic and duodenal homeobox gene-1 (PDX-1) plays a crucial role in beta-cell differentiation, and maintaining mature beta-cell function. Thus, it is important to understand how pdx-1 gene is regulated under various pathophysiological conditions in vivo. In this study, to non-invasively and quantitatively monitor pdx-1 promoter activity in vivo, we constructed a pdx-1 promoter-SEAP-IRES-GFP reporter plasmid. In this construct, the -4.6kb pdx-1 promoter region sufficient for driving beta-cell-selective PDX-1 expression was inserted to the upstream of the secreted alkaline phosphatase (SEAP) reporter gene. It is noted here that the pdx-1 promoter-mediated SEAP activity can be distinguished from endogenous alkaline phosphatase activity. First, we transfected the construct in mouse beta-cell line MIN6 and human hepatocellular carcinoma cell line HepG2. SEAP activity was readily detected in the media of MIN6 cells, but not in HepG2 cells. These results indicate that this construct specifically reports beta-cell-specific pdx-1 promoter activity in a cell culture system. Based on these in vitro findings, we next generated transgenic mice using the same construct. SEAP activity was readily detected in serum of the transgenic mice, but not in their littermate mice. Furthermore, SEAP activity was detected in protein extract from the transgenic pancreas and slightly from the transgenic duodenum, but not from the liver, and brain. These results indicate that serum SEAP activity likely represents in vivo pdx-1 promoter activity. This transgenic mouse model would be useful to non-invasively monitor in vivo pdx-1 promoter activity and to screen new molecules which regulate PDX-1 expression.
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Affiliation(s)
- Toshihiko Shiraiwa
- Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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50
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Babu DA, Deering TG, Mirmira RG. A feat of metabolic proportions: Pdx1 orchestrates islet development and function in the maintenance of glucose homeostasis. Mol Genet Metab 2007; 92:43-55. [PMID: 17659992 PMCID: PMC2042521 DOI: 10.1016/j.ymgme.2007.06.008] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2007] [Revised: 06/14/2007] [Accepted: 06/15/2007] [Indexed: 01/30/2023]
Abstract
Emerging evidence over the past decade indicates a central role for transcription factors in the embryonic development of pancreatic islets and the consequent maintenance of normal glucose homeostasis. Pancreatic and duodenal homeobox 1 (Pdx1) is the best studied and perhaps most important of these factors. Whereas deletion or inactivating mutations of the Pdx1 gene causes whole pancreas agenesis in both mice and humans, even haploinsufficiency of the gene or alterations in its expression in mature islet cells causes substantial impairments in glucose tolerance and the development of a late-onset form of diabetes known as maturity onset diabetes of the young. The study of Pdx1 has revealed crucial phenotypic interrelationships of the varied cell types within the pancreas, particularly as these impinge upon cellular differentiation in the embryo and neogenesis and regeneration in the adult. In this review, we describe the actions of Pdx1 in the developing and mature pancreas and attempt to unify these actions with its known roles in modulating transcriptional complex formation and chromatin structure at the molecular genetic level.
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Affiliation(s)
- Daniella A. Babu
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908 USA
| | - Tye G. Deering
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908 USA
| | - Raghavendra G. Mirmira
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908 USA
- Diabetes Center, Department of Medicine, University of Virginia, Charlottesville, VA 22908 USA
- To whom correspondence should be addressed: University of Virginia Health System, 450 Ray C. Hunt Drive, Box 801407, Charlottesville, VA 22908. E-mail: , Telephone: 434-924-9416, Fax: 434-982-3796
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