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Srisutha J, Watari I, Akakura M, Watanabe M, Changsiripun C, Ono T. P2X7R and P2X4R expression of mice submandibular gland in high-fat diet/streptozotocin-induced type 2 diabetes. Sci Rep 2024; 14:10855. [PMID: 38740782 PMCID: PMC11091137 DOI: 10.1038/s41598-024-60519-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 04/24/2024] [Indexed: 05/16/2024] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a chronic inflammatory disease that can compromise the functioning of various organs, including the salivary glands (SG). The purinergic system is one of the most important inflammatory pathways in T2DM condition, and P2X7R and P2X4R are the primary purinergic receptors in SG that regulate inflammatory homeostasis. This study aimed to evaluate P2X7R and P2X4R expression, and morphological changes in the submandibular gland (SMG) in T2DM. Twenty-four 5-week-old mice were randomly assigned to control (CON) and diabetes mellitus (DM) groups (n = 12 each). Body weight, diet, and blood glucose levels were monitored weekly. The histomorphology of the SMG and the expression of the P2X7R, and P2X7R was evaluated by immunohistochemistry (IHC) staining and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) at 11 and 13 weeks of age. Our findings indicate a significant increase in food consumption, body weight, and blood glucose levels in the DM group. Although a significant increase in P2X7R and P2X4R expression was observed in the DM groups, the receptor location remained unchanged. We also observed a significant increase in the acinar area in the DM13w group, and a significant decrease in the ductal area in the DM11w and DM13w groups. Targeting purinergic receptors may offer novel therapeutic methods for diabetic complications.
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MESH Headings
- Animals
- Mice
- Blood Glucose/metabolism
- Body Weight
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 2/chemically induced
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Diet, High-Fat/adverse effects
- Mice, Inbred C57BL
- Receptors, Purinergic P2X4/metabolism
- Receptors, Purinergic P2X4/genetics
- Receptors, Purinergic P2X7/metabolism
- Receptors, Purinergic P2X7/genetics
- Streptozocin
- Submandibular Gland/metabolism
- Submandibular Gland/pathology
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Affiliation(s)
- Jiratchaya Srisutha
- Department of Orthodontic Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo city, Tokyo, 113-8510, Japan
- Department of Orthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Ippei Watari
- Department of Orthodontic Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo city, Tokyo, 113-8510, Japan.
| | - Masato Akakura
- Department of Orthodontic Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo city, Tokyo, 113-8510, Japan
| | - Minami Watanabe
- Department of Orthodontic Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo city, Tokyo, 113-8510, Japan
| | - Chidsanu Changsiripun
- Department of Orthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Takashi Ono
- Department of Orthodontic Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo city, Tokyo, 113-8510, Japan
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2
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Walker JT, Saunders DC, Rai V, Chen HH, Orchard P, Dai C, Pettway YD, Hopkirk AL, Reihsmann CV, Tao Y, Fan S, Shrestha S, Varshney A, Petty LE, Wright JJ, Ventresca C, Agarwala S, Aramandla R, Poffenberger G, Jenkins R, Mei S, Hart NJ, Phillips S, Kang H, Greiner DL, Shultz LD, Bottino R, Liu J, Below JE, Parker SCJ, Powers AC, Brissova M. Genetic risk converges on regulatory networks mediating early type 2 diabetes. Nature 2023; 624:621-629. [PMID: 38049589 DOI: 10.1038/s41586-023-06693-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 09/28/2023] [Indexed: 12/06/2023]
Abstract
Type 2 diabetes mellitus (T2D), a major cause of worldwide morbidity and mortality, is characterized by dysfunction of insulin-producing pancreatic islet β cells1,2. T2D genome-wide association studies (GWAS) have identified hundreds of signals in non-coding and β cell regulatory genomic regions, but deciphering their biological mechanisms remains challenging3-5. Here, to identify early disease-driving events, we performed traditional and multiplexed pancreatic tissue imaging, sorted-islet cell transcriptomics and islet functional analysis of early-stage T2D and control donors. By integrating diverse modalities, we show that early-stage T2D is characterized by β cell-intrinsic defects that can be proportioned into gene regulatory modules with enrichment in signals of genetic risk. After identifying the β cell hub gene and transcription factor RFX6 within one such module, we demonstrated multiple layers of genetic risk that converge on an RFX6-mediated network to reduce insulin secretion by β cells. RFX6 perturbation in primary human islet cells alters β cell chromatin architecture at regions enriched for T2D GWAS signals, and population-scale genetic analyses causally link genetically predicted reduced RFX6 expression with increased T2D risk. Understanding the molecular mechanisms of complex, systemic diseases necessitates integration of signals from multiple molecules, cells, organs and individuals, and thus we anticipate that this approach will be a useful template to identify and validate key regulatory networks and master hub genes for other diseases or traits using GWAS data.
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Affiliation(s)
- John T Walker
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Diane C Saunders
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Vivek Rai
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Hung-Hsin Chen
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Peter Orchard
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Chunhua Dai
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yasminye D Pettway
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Alexander L Hopkirk
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Conrad V Reihsmann
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yicheng Tao
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Simin Fan
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Shristi Shrestha
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Arushi Varshney
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Lauren E Petty
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jordan J Wright
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Christa Ventresca
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
| | - Samir Agarwala
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Radhika Aramandla
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Greg Poffenberger
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Regina Jenkins
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Shaojun Mei
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Nathaniel J Hart
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sharon Phillips
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Hakmook Kang
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Dale L Greiner
- Department of Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, MA, USA
| | | | - Rita Bottino
- Imagine Pharma, Devon, PA, USA
- Institute of Cellular Therapeutics, Allegheny-Singer Research Institute, Allegheny Health Network, Pittsburgh, PA, USA
| | - Jie Liu
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Jennifer E Below
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Stephen C J Parker
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA.
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA.
- Department of Biostatistics, University of Michigan, Ann Arbor, MI, USA.
| | - Alvin C Powers
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA.
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
- VA Tennessee Valley Healthcare System, Nashville, TN, USA.
| | - Marcela Brissova
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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Asuaje Pfeifer M, Langehein H, Grupe K, Müller S, Seyda J, Liebmann M, Rustenbeck I, Scherneck S. PyCreas: a tool for quantification of localization and distribution of endocrine cell types in the islets of Langerhans. Front Endocrinol (Lausanne) 2023; 14:1250023. [PMID: 37772078 PMCID: PMC10523144 DOI: 10.3389/fendo.2023.1250023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 08/25/2023] [Indexed: 09/30/2023] Open
Abstract
Manifest diabetes, but also conditions of increased insulin resistance such as pregnancy or obesity can lead to islet architecture remodeling. The contributing mechanisms are as poorly understood as the consequences of altered cell arrangement. For the quantification of the different cell types but also the frequency of different cell-cell contacts within the islets, different approaches exist. However, few methods are available to characterize islet cell distribution in a statistically valid manner. Here we describe PyCreas, an open-source tool written in Python that allows semi-automated analysis of islet cell distribution based on images of pancreatic sections stained by immunohistochemistry or immunofluorescence. To ensure that the PyCreas tool is suitable for quantitative analysis of cell distribution in the islets at different metabolic states, we studied the localization and distribution of alpha, beta, and delta cells during gestation and prediabetes. We compared the islet cell distribution of pancreatic islets from metabolically healthy NMRI mice with that of New Zealand obese (NZO) mice, which exhibit impaired glucose tolerance (IGT) both preconceptionally and during gestation, and from C57BL/6 N (B6) mice, which acquire this IGT only during gestation. Since substrain(s) of the NZO mice are known to show a variant in the Abcc8 gene, we additionally examined preconceptional SUR1 knock-out (SUR1-KO) mice. PyCreas provided quantitative evidence that alterations in the Abcc8 gene are associated with an altered distribution pattern of islet cells. Moreover, our data indicate that this cannot be a consequence of prolonged hyperglycemia, as islet architecture is already altered in the prediabetic state. Furthermore, the quantitative analysis suggests that states of transient IGT, such as during common gestational diabetes mellitus (GDM), are not associated with changes in islet architecture as observed during long-term IGT. PyCreas provides the ability to systematically analyze the localization and distribution of islet cells at different stages of metabolic disease to better understand the underlying pathophysiology.
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Affiliation(s)
| | | | | | | | | | | | | | - Stephan Scherneck
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, Braunschweig, Germany
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St. Clair JR, Westacott MJ, Miranda J, Farnsworth NL, Kravets V, Schleicher WE, Dwulet JM, Levitt CH, Heintz A, Ludin NWF, Benninger RKP. Restoring connexin-36 function in diabetogenic environments precludes mouse and human islet dysfunction. J Physiol 2023; 601:4053-4072. [PMID: 37578890 PMCID: PMC10508056 DOI: 10.1113/jp282114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 07/27/2023] [Indexed: 08/16/2023] Open
Abstract
The secretion of insulin from β-cells in the islet of Langerhans is governed by a series of metabolic and electrical events, which can fail during the progression of type 2 diabetes (T2D). β-cells are electrically coupled via connexin-36 (Cx36) gap junction channels, which coordinates the pulsatile dynamics of [Ca2+ ] and insulin release across the islet. Factors such as pro-inflammatory cytokines and free fatty acids disrupt gap junction coupling under in vitro conditions. Here we test whether gap junction coupling and coordinated [Ca2+ ] dynamics are disrupted in T2D, and whether recovery of gap junction coupling can recover islet function. We examine islets from donors with T2D, from db/db mice, and islets treated with pro-inflammatory cytokines (TNF-α, IL-1β, IFN-ɣ) or free fatty acids (palmitate). We modulate gap junction coupling using Cx36 over-expression or pharmacological activation via modafinil. We also develop a peptide mimetic (S293) of the c-terminal regulatory site of Cx36 designed to compete against its phosphorylation. Cx36 gap junction permeability and [Ca2+ ] dynamics were disrupted in islets from both human donors with T2D and db/db mice, and in islets treated with pro-inflammatory cytokines or palmitate. Cx36 over-expression, modafinil treatment and S293 peptide all enhanced Cx36 gap junction coupling and protected against declines in coordinated [Ca2+ ] dynamics. Cx36 over-expression and S293 peptide also reduced apoptosis induced by pro-inflammatory cytokines. Critically, S293 peptide rescued gap junction coupling and [Ca2+ ] dynamics in islets from both db/db mice and a sub-set of T2D donors. Thus, recovering or enhancing Cx36 gap junction coupling can improve islet function in diabetes. KEY POINTS: Connexin-36 (Cx36) gap junction permeability and associated coordination of [Ca2+ ] dynamics is diminished in human type 2 diabetes (T2D) and mouse models of T2D. Enhancing Cx36 gap junction permeability protects against disruptions to the coordination of [Ca2+ ] dynamics. A novel peptide mimetic of the Cx36 c-terminal regulatory region protects against declines in Cx36 gap junction permeability. Pharmacological elevation in Cx36 or Cx36 peptide mimetic recovers [Ca2+ ] dynamics and glucose-stimulated insulin secretion in human T2D and mouse models of T2D.
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Affiliation(s)
- Joshua R St. Clair
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Matthew J Westacott
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Jose Miranda
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Nikki L Farnsworth
- Barbara Davis Center for Diabetes, University of Colorado
Denver | Anschutz Medical Campus, Aurora, CO
| | - Vira Kravets
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Wolfgang E Schleicher
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - JaeAnn M Dwulet
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Claire H Levitt
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Audrey Heintz
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Nurin WF Ludin
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
| | - Richard KP Benninger
- Department of Bioengineering, University of Colorado Denver
| Anschutz Medical Campus, Aurora, CO
- Barbara Davis Center for Diabetes, University of Colorado
Denver | Anschutz Medical Campus, Aurora, CO
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5
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Iftikhar A, Nausheen R, Khurshid M, Iqbal RK, Muzaffar H, Malik A, Ali Khan A, Batool F, Akhtar S, Yasin A, Anwar H. Pancreatic regenerative potential of manuka honey evidenced through pancreatic histology and levels of transcription factors in diabetic rat model. Heliyon 2023; 9:e20017. [PMID: 37809953 PMCID: PMC10559747 DOI: 10.1016/j.heliyon.2023.e20017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/18/2023] [Accepted: 09/08/2023] [Indexed: 10/10/2023] Open
Abstract
Background Diabetes mellitus is a commonly occurring metabolic disorder accompanied by high morbidity and alarming mortality. Besides various available therapies, induction of pancreatic regeneration has emerged as a promising strategy for alleviating the damaging effect of diabetes. Honey, a potent antioxidative and anti-inflammatory agent, has been reported in the literature archive to exhibit favourable results in the regeneration process of several organ systems. Design The current research work was intended to explore the potential role of manuka honey in pancreatic regeneration in alloxan-induced diabetic rats by accessing the pancreatic histology and levels of relevant transcription factors, including MAFA, PDX-1, INS-1, INS-2, NEUROG3, NKX6-1, and NEUROD. An equal number of rats were allocated to all four experimental groups: normal, negative control, positive control, and treatment group. Diabetes was induced in all groups except normal through a single intraperitoneal dose of alloxan monohydrate. No subsequent treatment was given to the negative control group, while the positive control and treatment groups were supplemented with metformin (150 mg/kg/day) and manuka honey (3 g/kg/day), respectively. Results Statistical comparison of glucose and insulin levels, oxidative stress indicators, changes in the architecture of pancreatic islets, and expression levels of regeneration-associated transcription factors advocated the potential role of manuka honey in ameliorating the alloxan-induced hyperglycaemia, hyperinsulinemia, oxidative stress, and necrotic changes in islets along with significant upregulation of relevant transcription factors. Conclusion This suggests to us the auspicious role of antioxidants in honey in pancreatic regeneration and advocates the favourable role of manuka honey in combating diabetes mellitus.
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Affiliation(s)
- Arslan Iftikhar
- Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Rimsha Nausheen
- Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Mohsin Khurshid
- Institute of Microbiology, Government College University, Faisalabad, Pakistan
| | - Rana Khalid Iqbal
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan
| | - Humaira Muzaffar
- Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Abdul Malik
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Azmat Ali Khan
- Pharmaceutical Biotechnology Laboratory, Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Farwah Batool
- Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Suhail Akhtar
- Department of Biochemistry, A.T. Still University of Health Sciences, Kirksville, MO, USA
| | - Ayesha Yasin
- Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Haseeb Anwar
- Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
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Khalifa J, Bourgault S, Gaudreault R. Interactions of Polyphenolic Gallotannins with Amyloidogenic Polypeptides Associated with Alzheimer's Disease: From Molecular Insights to Physiological Significance. Curr Alzheimer Res 2023; 20:603-617. [PMID: 38270140 DOI: 10.2174/0115672050277001231213073043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/30/2023] [Accepted: 11/10/2023] [Indexed: 01/26/2024]
Abstract
Polyphenols are natural compounds abundantly found in plants. They are known for their numerous benefits to human health, including antioxidant properties and anti-inflammatory activities. Interestingly, many studies have revealed that polyphenols can also modulate the formation of amyloid fibrils associated with disease states and can prevent the formation of cytotoxic oligomer species. In this review, we underline the numerous effects of four hydrolysable gallotannins (HGTs) with high conformational flexibility, low toxicity, and multi-targeticity, e.g., tannic acid, pentagalloyl glucose, corilagin, and 1,3,6-tri-O-galloyl-β-D-glucose, on the aggregation of amyloidogenic proteins associated with the Alzheimer's Disease (AD). These HGTs have demonstrated interesting abilities to reduce, at different levels, the formation of amyloid fibrils involved in AD, including those assembled from the amyloid β-peptide, the tubulin-associated unit, and the islet amyloid polypeptide. HGTs were also shown to disassemble pre-formed fibrils and to diminish cognitive decline in mice. Finally, this manuscript highlights the importance of further investigating these naturally occurring HGTs as promising scaffolds to design molecules that can interfere with the formation of proteotoxic oligomers and aggregates associated with AD pathogenesis.
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Affiliation(s)
- Jihane Khalifa
- Département de Chimie, Université du Québec à Montréal, 2101 Rue Jeanne-Mance, Montréal, QC, H2X 2J6, Canada
- Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Canada
- Quebec Centre for Advanced Materials (QCAM), 3420 University Street, Montréal, QC, H2X 3Y7, Canada
| | - Steve Bourgault
- Département de Chimie, Université du Québec à Montréal, 2101 Rue Jeanne-Mance, Montréal, QC, H2X 2J6, Canada
- Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Canada
| | - Roger Gaudreault
- Département de Chimie, Université du Québec à Montréal, 2101 Rue Jeanne-Mance, Montréal, QC, H2X 2J6, Canada
- Quebec Centre for Advanced Materials (QCAM), 3420 University Street, Montréal, QC, H2X 3Y7, Canada
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Mkolo NM, Olaokun OO, King PH, Janse van Rensburg I, Eloff JN, Naidoo V. Verification of the folkloric and anecdotal antidiabetic effects of Hypoxis hemerocallidea (Fisch., C.A. Mey. & Avé-Lall) and isolated, β-sitosterol using early-stage type II spontaneous diabetic mutant BKS-Leprdb mice. BMC Complement Med Ther 2022; 22:163. [PMID: 35725532 PMCID: PMC9208228 DOI: 10.1186/s12906-022-03640-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 06/09/2022] [Indexed: 11/25/2022] Open
Abstract
Background Previous studies in our laboratory in ex vivo assays have demonstrated H. hemerocallidea extract as potential antidiabetic agent through increased insulin release from pancreatic beta cells. Thus, for this study the early stage type II spontaneous diabetic mutant mice model was used to evaluate and determine the degree of the antidiabetic efficacy of H. hemerocallidea. Methods Eight-weeks-old type II spontaneous pre-diabetic mutant BKS-Leprdb mice were fed with feed supplemented with either H. hemerocallidea extract, isolated compound (β-sitosterol) or chlorpropamide (positive control) for 4 weeks. The haematological parameters, clinical chemistry, glucose tolerance, feed intake, faecal output and body weights were measured. Results The blood glucose concentrations of all the animals treated with plant extract, β-sitosterol compound and non-treated pre-diabetic animals did not return to baseline levels. Only the β-sitosterol treatment and positive control groups resulted in a respective small decrease of 5.8 and 5.2% in the mouse weights over the study period, with no significant changes (p > 0.05) in food intake. However, there was a general trend for decrease in faecal output for all the groups. Albumin, triglycerides, and total cholesterol levels in β-sitosterol and chlorpropamide-treated animals were lower, relative to untreated-animals. Animals fed with plant extract showed large amounts of internal fat. There were no significant changes (p > 0.05) in total serum protein, globulin, alanine aminotransferase, alkaline phosphatase, urea nitrogen and creatinine attributed to administration of treatments. In all groups, some animals showed lesions associated with cardiac puncture. Few animals except animals treated with plant extract, showed presence of a left-ventricular hypertrophic cardiomyopathy. The liver and kidneys for all groups appeared macroscopically normal and the thymuses were small (±2 mg). There were pathological signs in some of the animals particularly in myocardial fibres, renal tubular, glomerular, hepatocyte granularity and pancreas islets. However, there was no significance trend between the groups. Conclusion Based on the results, none of the treatments could be considered highly effective for the management of type II pre-diabetes as sole therapeutic intervention. Supplementary Information The online version contains supplementary material available at 10.1186/s12906-022-03640-y.
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Walker JT, Saunders DC, Brissova M, Powers AC. The Human Islet: Mini-Organ With Mega-Impact. Endocr Rev 2021; 42:605-657. [PMID: 33844836 PMCID: PMC8476939 DOI: 10.1210/endrev/bnab010] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Indexed: 02/08/2023]
Abstract
This review focuses on the human pancreatic islet-including its structure, cell composition, development, function, and dysfunction. After providing a historical timeline of key discoveries about human islets over the past century, we describe new research approaches and technologies that are being used to study human islets and how these are providing insight into human islet physiology and pathophysiology. We also describe changes or adaptations in human islets in response to physiologic challenges such as pregnancy, aging, and insulin resistance and discuss islet changes in human diabetes of many forms. We outline current and future interventions being developed to protect, restore, or replace human islets. The review also highlights unresolved questions about human islets and proposes areas where additional research on human islets is needed.
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Affiliation(s)
- John T Walker
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Diane C Saunders
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Marcela Brissova
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Alvin C Powers
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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Garba HA, Mohammed A, Ibrahim MA, Shuaibu MN. Effect of lemongrass (Cymbopogon citratus Stapf) tea in a type 2 diabetes rat model. CLINICAL PHYTOSCIENCE 2020. [DOI: 10.1186/s40816-020-00167-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Lemongrass (Cymbopogon citratus Stapf) tea is a widely consumed beverage for nourishment and the remedy of diabetes mellitus (DM) in Africa locally. The aim of the present study was to investigate the antidiabetic action of lemongrass tea (LGT) in a type 2 diabetes (T2D) model of rats.
Methods
The fructose-streptozotocin (STZ) animal model for T2D was used and the LGT was prepared by boiling for 10 min in water, allowed to cool and administered at 0.25 or 0.5% (ad libitum), for 4 weeks to the T2D rats.
Results
The LGT showed higher phytochemical contents compared to the cold-water extract. The diabetic untreated animals exhibited significantly (p < 0.05) higher serum glucose and lipids, insulin resistance (HOMA-IR) index with a significantly lower (p < 0.05) levels of serum insulin, β-cell function (HOMA-β) and liver glycogen compared to the normal animals. Oral supplemented of LGT for 4 weeks improved these changes comparable to the metformin treated group.
Conclusion
The data suggests that LGT intake had excellent antidiabetic effect in a T2D model of rats attributed to the higher content of the ingredients.
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Maternal N-Acetyl Cysteine Intake Improved Glucose Tolerance in Obese Mice Offspring. Int J Mol Sci 2020; 21:ijms21061981. [PMID: 32183232 PMCID: PMC7139991 DOI: 10.3390/ijms21061981] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/20/2020] [Accepted: 03/09/2020] [Indexed: 12/17/2022] Open
Abstract
Exposure to certain environmental factors during the early stages of development was found to affect health in adulthood. Among other environmental factors, oxidative stress has been suggested to be involved in fetal programming, leading to elevated risk for metabolic disorders, including type 2 diabetes; however, the possibility that antioxidant consumption during early life may affect the development of diabetes has scarcely been studied. The aim of this study was to investigate the effects of N-acetyl-l-cysteine (NAC) given during pregnancy and lactation on the susceptibility of offspring to develop glucose intolerance at adulthood. C57bl6/J mice were given NAC during pregnancy and lactation. High fat diet (HFD) was given to offspring at an age of 6 weeks for an additional 9 weeks, till the end of the study. Isolated islets of NAC-treated offspring (6 weeks old, before HFD feeding) had an increased efficacy of glucose-stimulated insulin secretion and a higher resistance to oxidative damage. Following HFD feeding, glucose tolerance and insulin sensitivity of NAC-treated offspring were improved. In addition, islet diameter was lower in male offspring of NAC-treated mice compared to their HFD-fed littermates. NAC consumption during early life improves glucose tolerance in adulthood in mice.
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11
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Yadav R, Dey DK, Vij R, Meena S, Kapila R, Kapila S. Evaluation of anti-diabetic attributes of Lactobacillus rhamnosus MTCC: 5957, Lactobacillus rhamnosus MTCC: 5897 and Lactobacillus fermentum MTCC: 5898 in streptozotocin induced diabetic rats. Microb Pathog 2018; 125:454-462. [PMID: 30316007 DOI: 10.1016/j.micpath.2018.10.015] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/09/2018] [Accepted: 10/10/2018] [Indexed: 12/11/2022]
Abstract
Interest in probiotics has grown significantly in the last decades due to their reported nutritional and health promoting effects. The aim of this study is to investigate the therapeutic potential of probiotic fermented milk (PFM) prepared using three different probiotic strains i.e. Lactobacillus rhamnosus MTCC: 5957, Lactobacillus rhamnosus MTCC: 5897 and Lactobacillus fermentum MTCC: 5898; independently or in combination, for treating streptozotocin induced type-1 diabetes in male Wistar rats. Diabetic rats were fed with PFM preparations for 6 weeks and then analyzed for the various biochemical parameters associated. The results indicated that feeding of PFM significantly improved glucose metabolism (fasting blood glucose, glycated hemoglobin, serum insulin), serum inflammation status (tumor necrosis factor-α, and serum interleukin-6), oxidative stress (thiobarbituric acid reactive substance, catalase, superoxide dismutase and glutathione peroxidase activities in liver and kidney), serum lipid profile (total cholesterol, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol, triglycerides) in diabetic rats. In addition, feeding of PFM has significantly reduced mRNA expression of pepck and g6pase genes that code the key enzymes of gluconeogenesis pathway. The results of this study showed that daily consumption of PFM can be effective in combating of type -1 diabetes and its complications.
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Affiliation(s)
- Radha Yadav
- Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
| | - Debpriyo Kumar Dey
- Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
| | - Rishika Vij
- Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
| | - Sunita Meena
- Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
| | - Rajeev Kapila
- Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
| | - Suman Kapila
- Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
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Lundberg M, Stenwall A, Tegehall A, Korsgren O, Skog O. Expression profiles of stress-related genes in islets from donors with progressively impaired glucose metabolism. Islets 2018; 10:69-79. [PMID: 29446696 PMCID: PMC5895176 DOI: 10.1080/19382014.2018.1433980] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
It is currently unknown how the islet transcriptional pattern changes as glucose metabolism deteriorates and progresses to fulminant type 2 diabetes (T2D). In this study, we hypothesized that islets from donors with elevated HbA1c levels, but not yet diagnosed with T2D, would show signs of cell stress on a transcriptional level. Laser capture microdissection and qPCR arrays including 330 genes related to mitochondria, oxidative stress, or the unfolded protein response were used to extract and analyze islets from organ donors with HbA1c <5.5% (37 mmol/mol), elevated HbA1c (6.0-6.5% (42-48 mmol/mol)), high HbA1c (>6.5% (48 mmol/mol)) or established T2D. Principal component analysis and hierarchical clustering based on the expression of all 330 genes displayed no obvious separation of the four different donor groups, indicating that the inter-donor variations were larger than the differences between groups. However, 44 genes were differentially expressed (P < 0.05, false discovery rate <30%) between islets from donors with HbA1c <5.5% (37 mmol/mol) compared with islets from T2D subjects. Twelve genes were differentially expressed compared to control islets in both donors with established T2D and donors with elevated HbA1c (6.0-6.5% (42-48 mmol/mol)). Overexpressed genes were related mainly to the unfolded protein response, whereas underexpressed genes were related to mitochondria. Our data on transcriptional changes in human islets retrieved by LCM from high-quality biopsies, as pre-diabetes progresses to established T2D, increase our understanding on how islet stress contributes to the disease development.
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Affiliation(s)
- Marcus Lundberg
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
- CONTACT Marcus Lundberg Uppsala University, Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory C11, 751 85 Uppsala, Sweden
| | - Anton Stenwall
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Angie Tegehall
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Olle Korsgren
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
- Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Oskar Skog
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
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Wedgwood KCA, Satin LS. Six degrees of depolarization: Comment on "Network science of biological systems at different scales: A review" by Marko Gosak et al. Phys Life Rev 2018; 24:136-139. [PMID: 29395878 DOI: 10.1016/j.plrev.2018.01.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Accepted: 01/18/2018] [Indexed: 11/17/2022]
Affiliation(s)
| | - Leslie S Satin
- University of Michigan Medical School, Ann Arbor, MI, USA
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14
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Thivolet C, Vial G, Cassel R, Rieusset J, Madec AM. Reduction of endoplasmic reticulum- mitochondria interactions in beta cells from patients with type 2 diabetes. PLoS One 2017; 12:e0182027. [PMID: 28742858 PMCID: PMC5526536 DOI: 10.1371/journal.pone.0182027] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Accepted: 07/11/2017] [Indexed: 11/18/2022] Open
Abstract
Type 2 diabetes develops when beta cells are not able to fulfill insulin needs. The role of the endoplasmic reticulum-mitochondria junction in coordinating the functions of these two organelles throughout the natural history of type 2 diabetes is determinant and may explain the alterations of insulin biosynthesis. Our goal was to study endoplasmic reticulum and mitochondrial interactions in human beta cells from organ donors with type 2 diabetes. Pancreas samples were obtained via the network for pancreatic organ donors with diabetes (nPOD) based on disease status with 12 subjects with type 2 diabetes and 9 non-diabetic controls. We examined pancreatic specimens by immunofluorescence, in situ hybridization and in situ proximity ligation assay and compared the results to an in vitro model of beta-cell dysfunction. Expression of proteins that enable tethering and exchanges between endoplasmic reticulum (ER) and mitochondria and quantification of interconnection through mitochondria associated membranes (MAM) was investigated. In beta cells from type 2 diabetic cases as compared to controls, there was a significant increase in reticular expression of inositol triphosphate receptor-2 (IP3R2) both at the protein and mRNA levels, no difference in mitochondrial transit peptide receptor TOM20 and mitofusin-2 expressions, and a decrease in the expression of voltage-dependent anion channel-1 (VDAC-1). The number of IP3R2-VDAC-1 complexes identified by in situ proximity ligation assay was significantly lower in diabetic islets and in beta cells of diabetics as compared to controls. Treatment of Min6-B1 cells with palmitate altered glucose-stimulated insulin secretion, increased ER stress and significantly reduced ER-mitochondrial interactions. We can conclude that specific changes in reticular and mitochondrial beta cell proteins characterize human type 2 diabetes with reduction in organelle interactions. This finding opens new targets of intervention.
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Affiliation(s)
- Charles Thivolet
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
- Hospices Civils de Lyon, Lyon-Sud Hospital, Department of Endocrinology and Diabetes, Pierre-Bénite, France
- * E-mail:
| | - Guillaume Vial
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
| | - Romeo Cassel
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
| | - Jennifer Rieusset
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
| | - Anne-Marie Madec
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
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Lundberg M, Seiron P, Ingvast S, Korsgren O, Skog O. Insulitis in human diabetes: a histological evaluation of donor pancreases. Diabetologia 2017; 60:346-353. [PMID: 27796420 PMCID: PMC6518093 DOI: 10.1007/s00125-016-4140-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/27/2016] [Indexed: 01/05/2023]
Abstract
AIMS/HYPOTHESIS According to the consensus criteria developed for type 1 diabetes, an individual can be diagnosed with insulitis when ≥ 15 CD45+ cells are found within the parenchyma or in the islet-exocrine interface in ≥ 3 islets. The aim of this study was to determine the frequency of individuals with type 2 diabetes fulfilling these criteria with reference to non-diabetic and type 1 diabetic individuals. METHODS Insulitis was determined by examining CD45+ cells in the pancreases of 50, 13 and 44 organ donors with type 2 diabetes, type 1 diabetes and no diabetes, respectively. CD3+ cells (T cells) infiltrating the islets were evaluated in insulitic donors. In insulitic donors with type 2 diabetes, the pancreases were characterised according to the presence of CD68 (macrophages), myeloperoxidase (MPO; neutrophils), CD3, CD20 (B cells) and HLA class I hyperstained islets. In all type 2 diabetic donors, potential correlations of insulitis with dynamic glucose-stimulated insulin secretion in vitro or age, BMI, HbA1c or autoantibody positivity were examined. RESULTS Overall, 28% of the type 2 diabetic donors fulfilled the consensus criteria for insulitis developed for type 1 diabetes. Of the type 1 diabetic donors, 31% fulfilled the criteria. None of the non-diabetic donors met the criteria. Only type 1 diabetic donors had ≥ 15 CD3+ cells in ≥ 3 islets. Type 2 diabetic donors with insulitis also had a substantial number of CD45+ cells in the exocrine parenchyma. Macrophages constituted the largest fraction of CD45+ cells, followed by neutrophils and T cells. Of type 2 diabetic pancreases with insulitis, 36% contained islets that hyperstained for HLA class I. Isolated islets from type 2 diabetic donors secreted less insulin than controls, although with preserved dynamics. Insulitis in the type 2 diabetic donors did not correlate with glucose-stimulated insulin secretion, the presence of autoantibodies, BMI or HbA1c. CONCLUSIONS/INTERPRETATION The current definition of insulitis cannot be used to distinguish pancreases retrieved from individuals with type 1 diabetes from those with type 2 diabetes. On the basis of our findings, we propose a revised definition of insulitis, with a positive diagnosis when ≥ 15 CD3+ cells, not CD45+ cells, are found in ≥ 3 islets.
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Affiliation(s)
- Marcus Lundberg
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory C11, Clinical Immunology, Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden.
| | - Peter Seiron
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory C11, Clinical Immunology, Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Sofie Ingvast
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory C11, Clinical Immunology, Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Olle Korsgren
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory C11, Clinical Immunology, Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Oskar Skog
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory C11, Clinical Immunology, Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
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16
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Erickson RI, Schutt LK, Tarrant JM, McDowell M, Liu L, Johnson AR, Lewin-Koh SC, Hedehus M, Ross J, Carano RAD, Staflin K, Zhong F, Crawford JJ, Zhong S, Reif K, Katewa A, Wong H, Young WB, Dambach DM, Misner DL. Bruton’s Tyrosine Kinase Small Molecule Inhibitors Induce a Distinct Pancreatic Toxicity in Rats. J Pharmacol Exp Ther 2016; 360:226-238. [DOI: 10.1124/jpet.116.236224] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 10/31/2016] [Indexed: 12/21/2022] Open
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Abstract
OBJECTIVE Abnormalities in exocrine pancreatic function have been reported in diabetes mellitus (DM). We reviewed published literature to determine the nature of structural and functional alterations in the exocrine pancreas in DM. METHODS We identified and abstracted data from original studies (n = 50) describing morphological, structural, and functional changes in the exocrine pancreas in types 1 and 2 DM. RESULTS Pancreatic weight and volume are markedly lower in type 1 DM (P < 0.005) with insignificant decrease in type 2 DM compared with age-, sex-, and body mass index-matched controls. Pancreatic histopathological changes seen in most subjects with DM at autopsy (n = 7 studies, 1272 autopsies) include mild-to-marked interacinar fibrosis, scant inflammatory infiltrate, no pancreatic ductal changes, and hyalinization of arteries. In subjects with DM, pooled prevalence of decreased fecal elastase 1 (<200 μg/g) is higher, coefficient of fat absorption is near normal (mean, 91%-94%), and pancreatic exocrine dysfunction is nonprogressive over time. Diabetes mellitus is asymptomatic in regard to the exocrine pancreas. CONCLUSIONS In types 1 and 2 DM, moderate-to-severe subclinical pancreatic fibrosis and modest exocrine dysfunction occurs in the absence of clinical or histopathological evidence of chronic pancreatitis. We call this novel entity "diabetic exocrine pancreatopathy."
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18
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Tomita T. Apoptosis in pancreatic β-islet cells in Type 2 diabetes. Bosn J Basic Med Sci 2016; 16:162-79. [PMID: 27209071 DOI: 10.17305/bjbms.2016.919] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 01/16/2016] [Accepted: 01/20/2016] [Indexed: 12/25/2022] Open
Abstract
Apoptosis plays important roles in the pathophysiology of Type 2 diabetes mellitus (T2DM). The etiology of T2DM is multifactorial, including obesity-associated insulin resistance, defective insulin secretion, and loss of β-cell mass through β-cell apoptosis. β-cell apoptosis is mediated through a milliard of caspase family cascade machinery in T2DM. The glucose-induced insulin secretion is the principle pathophysiology of diabetes and insufficient insulin secretion results in chronic hyperglycemia, diabetes. Recently, hyperglycemia-induced β-cell apoptosis has been extensively studied on the balance of pro-apoptotic Bcl-2 proteins (Bad, Bid, Bik, and Bax) and anti-apoptotic Bcl family (Bcl-2 and Bcl-xL) toward apoptosis in vitro isolated islets and insulinoma cell culture. Apoptosis can only occur when the concentration of pro-apoptotic Bcl-2 exceeds that of anti-apoptotic proteins at the mitochondrial membrane of the intrinsic pathway. A bulk of recent research on hyperglycemia-induced apoptosis on β-cells unveiled complex details on glucose toxicity on β-cells in molecular levels coupled with cell membrane potential by adenosine triphosphate generation through K+ channel closure, opening Ca2+ channel and plasma membrane depolarization. Furthermore, animal models using knockout mice will shed light on the basic understanding of the pathophysiology of diabetes as a glucose metabolic disease complex, on the balance of anti-apoptotic Bcl family and pro-apoptotic genes. The cumulative knowledge will provide a better understanding of glucose metabolism at a molecular level and will lead to eventual prevention and therapeutic application for T2DM with improving medications.
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19
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Cheng Y, Shen J, Ren W, Hao H, Xie Z, Liu J, Mu Y, Han W. Mild hyperglycemia triggered islet function recovery in streptozotocin-induced insulin-deficient diabetic rats. J Diabetes Investig 2016; 8:44-55. [PMID: 27184687 PMCID: PMC5217940 DOI: 10.1111/jdi.12540] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/26/2016] [Accepted: 05/10/2016] [Indexed: 01/09/2023] Open
Abstract
Aims/Introduction Moderate elevation of glucose level has been shown to effectively promote β‐cell replication in various models in vitro and in normal rodents. Here, we aimed to test the effect of moderately elevated glucose on β‐cell mass expansion and islet function recovery in diabetic animal models. Materials and Methods A single high dose of streptozotocin was given to induce insulin‐deficient diabetes in adult male Sprague–Dawley rats. Then, 48 h after streptozotocin injection, newly diabetic rats were randomly divided into three groups: (i) no treatment to maintain hyperglycemia; (ii) daily exogenous long‐acting human insulin analog injection that maintained mild hyperglycemia (15 mmol/L < blood glucose < 18 mmol/L); (iii) daily exogenous long‐acting human insulin analog injection to restore normoglycemia (blood glucose <8 mmol/L) as a control. Islet function, β‐cell regeneration and β‐cell replication were monitored during the entire analysis period. Results A single high dose of streptozotocin induced massive loss of β‐cells, resulting in irreversible hyperglycemia. Mild hyperglycemia markedly promoted β‐cell proliferation, leading to robust β‐cell regeneration. Importantly, rats that maintained mild hyperglycemia showed nearly normal glucose‐stimulated insulin secretion, glucose disposal and random blood glucose levels, suggesting almost full restoration of the islet function. Normalization of blood glucose levels profoundly blunted β‐cell replication, regeneration and islet function recovery observed in mild hyperglycemia. Conclusions Our research provides a feasible approach to stimulate in situ β‐cell regeneration in diabetic rats, offering new perspectives for diabetes therapy.
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Affiliation(s)
- Yu Cheng
- Department of Endocrinology, Chinese PLA General Hospital, Beijing, China.,Department of Molecular Biology, Institute of Basic Medicine, School of Life Science, Chinese PLA General Hospital, Beijing, China
| | - Jing Shen
- Department of Endocrinology, Chinese PLA 309 Hospital, Beijing, China
| | | | - Haojie Hao
- Department of Molecular Biology, Institute of Basic Medicine, School of Life Science, Chinese PLA General Hospital, Beijing, China
| | - Zongyan Xie
- Department of Endocrinology, Chinese PLA General Hospital, Beijing, China.,Department of Molecular Biology, Institute of Basic Medicine, School of Life Science, Chinese PLA General Hospital, Beijing, China
| | - Jiejie Liu
- Department of Molecular Biology, Institute of Basic Medicine, School of Life Science, Chinese PLA General Hospital, Beijing, China
| | - Yiming Mu
- Department of Endocrinology, Chinese PLA General Hospital, Beijing, China
| | - Weidong Han
- Department of Molecular Biology, Institute of Basic Medicine, School of Life Science, Chinese PLA General Hospital, Beijing, China
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20
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Striegel DA, Hara M, Periwal V. Adaptation of pancreatic islet cyto-architecture during development. Phys Biol 2016; 13:025004. [PMID: 27063927 DOI: 10.1088/1478-3975/13/2/025004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Plasma glucose in mammals is regulated by hormones secreted by the islets of Langerhans embedded in the exocrine pancreas. Islets consist of endocrine cells, primarily α, β, and δ cells, which secrete glucagon, insulin, and somatostatin, respectively. β cells form irregular locally connected clusters within islets that act in concert to secrete insulin upon glucose stimulation. Varying demands and available nutrients during development produce changes in the local connectivity of β cells in an islet. We showed in earlier work that graph theory provides a framework for the quantification of the seemingly stochastic cyto-architecture of β cells in an islet. To quantify the dynamics of endocrine connectivity during development requires a framework for characterizing changes in the probability distribution on the space of possible graphs, essentially a Fokker-Planck formalism on graphs. With large-scale imaging data for hundreds of thousands of islets containing millions of cells from human specimens, we show that this dynamics can be determined quantitatively. Requiring that rearrangement and cell addition processes match the observed dynamic developmental changes in quantitative topological graph characteristics strongly constrained possible processes. Our results suggest that there is a transient shift in preferred connectivity for β cells between 1-35 weeks and 12-24 months.
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Mohammed A, Koorbanally NA, Islam MS. Anti-diabetic effect of Xylopia aethiopica (Dunal) A. Rich. (Annonaceae) fruit acetone fraction in a type 2 diabetes model of rats. JOURNAL OF ETHNOPHARMACOLOGY 2016; 180:131-139. [PMID: 26795545 DOI: 10.1016/j.jep.2016.01.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 12/20/2015] [Accepted: 01/11/2016] [Indexed: 06/05/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE In traditional medicine from West Africa, the fruit decoction of Xylopia aethiopica (Dunal) A. Rich. is widely used for the treatment of diabetes mellitus (DM) either alone or in combination with other plants. The present study is designed to investigate the anti-diabetic effects of X. aethiopica acetone fraction (XAAF) from fruit ethanolic extract in a type 2 diabetes (T2D) model of rats. MATERIALS AND METHODS T2D was induced in rats by feeding a 10% fructose solution ad libitum for 2 weeks followed by a single intraperitoneal injection of streptozotocin (40 mg/kg body weight) and the animals were orally treated with 150 or 300 mg/kg body weight (bw) of the XAAF once daily for four weeks. RESULTS After 4 weeks study period, diabetic untreated animals (DBC) exhibited significantly higher serum glucose, serum fructosamine, LDH, CK-MB, serum lipids, liver glycogen, insulin resistance (HOMA-IR), AI, CRI and lower serum insulin, β-cell function (HOMA-β) and glucose tolerance ability compared to the normal animals. Histopathological examination of their pancreas revealed corresponding pathological changes in the islets and β-cells. These alterations were reverted to near-normal after the treatment of XAAF at 150 (DXAL) and 300 (DXAH) mg/kg bw with the effects being more pronounced in the DXAH group compared to the DXAL group. Moreover, the effects in the animals of DXAH group were comparable to the diabetic metformin (DMF) treated animals. In addition, no significant alterations were observed in non-diabetic animals treated with 300 mg/kg bw of XAAF (NXAH). CONCLUSION The results of our study suggest that XAAF treatment showed excellent anti-diabetic effects in a T2D model of rats.
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Affiliation(s)
- Aminu Mohammed
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal, (Westville Campus), Durban 4000, South Africa; Department of Biochemistry, Faculty of Science, Ahmadu Bello University, Zaria, Nigeria
| | - Neil Anthony Koorbanally
- Department of Chemistry, School of Chemistry and Physics, University of KwaZulu-Natal, (Westville Campus), Durban 4000, South Africa
| | - Md Shahidul Islam
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal, (Westville Campus), Durban 4000, South Africa.
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Lavallard V, Armanet M, Parnaud G, Meyer J, Barbieux C, Montanari E, Meier R, Morel P, Berney T, Bosco D. Cell rearrangement in transplanted human islets. FASEB J 2016; 30:748-760. [PMID: 26534832 DOI: 10.1096/fj.15-273805] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 10/13/2015] [Indexed: 11/03/2023]
Abstract
The major feature of the human pancreatic islet architecture is the organization of endocrine cells into clusters comprising central β cells and peripheral α cells surrounded by vasculature. To have an insight into the mechanisms that govern this unique islet architecture, islet cells were isolated, and reaggregation of α and β cells into islet-like structures (pseudoislets) after culture or transplantation into mice was studied by immunohistology. The pseudoislets formed in culture displayed an unusual cell arrangement, contrasting with the transplanted pseudoislets, which exhibited a cell arrangement similar to that observed in native pancreatic islet subunits. The pattern of revascularization and the distribution of extracellular matrix around transplanted pseudoislets were alike to those observed in native pancreatic islets. This organization of transplanted pseudoislets occurred also when revascularization was abolished by treating mice with an anti-VEGF antibody, but not when contact with extracellular matrix was prevented by encapsulation of pseudoislets within alginate hydrogel. These results indicate that the maintenance of islet cell arrangement is dependent on in vivo features such as extracellular matrix but independent of vascularization.
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Affiliation(s)
- Vanessa Lavallard
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Mathieu Armanet
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Géraldine Parnaud
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Jérémy Meyer
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Charlotte Barbieux
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Elisa Montanari
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Raphaël Meier
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Philippe Morel
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Thierry Berney
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
| | - Domenico Bosco
- *Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Cell Therapy Unit, Hôpital Saint Louis, Assistance Publique-Hôpitaux de Paris, and University Paris 7, Paris, France; and Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche Scientifique 1138, Centre de Recherches des Cordeliers, Paris, France
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Striegel DA, Hara M, Periwal V. The Beta Cell in Its Cluster: Stochastic Graphs of Beta Cell Connectivity in the Islets of Langerhans. PLoS Comput Biol 2015; 11:e1004423. [PMID: 26266953 PMCID: PMC4534467 DOI: 10.1371/journal.pcbi.1004423] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 07/02/2015] [Indexed: 12/25/2022] Open
Abstract
Pancreatic islets of Langerhans consist of endocrine cells, primarily α, β and δ cells, which secrete glucagon, insulin, and somatostatin, respectively, to regulate plasma glucose. β cells form irregular locally connected clusters within islets that act in concert to secrete insulin upon glucose stimulation. Due to the central functional significance of this local connectivity in the placement of β cells in an islet, it is important to characterize it quantitatively. However, quantification of the seemingly stochastic cytoarchitecture of β cells in an islet requires mathematical methods that can capture topological connectivity in the entire β-cell population in an islet. Graph theory provides such a framework. Using large-scale imaging data for thousands of islets containing hundreds of thousands of cells in human organ donor pancreata, we show that quantitative graph characteristics differ between control and type 2 diabetic islets. Further insight into the processes that shape and maintain this architecture is obtained by formulating a stochastic theory of β-cell rearrangement in whole islets, just as the normal equilibrium distribution of the Ornstein-Uhlenbeck process can be viewed as the result of the interplay between a random walk and a linear restoring force. Requiring that rearrangements maintain the observed quantitative topological graph characteristics strongly constrained possible processes. Our results suggest that β-cell rearrangement is dependent on its connectivity in order to maintain an optimal cluster size in both normal and T2D islets. High or low blood glucose levels are detrimental to human health. The hormone-secreting cells primarily responsible for maintaining glucose at physiologically appropriate levels are embedded in small clusters within the pancreas, the so-called islets of Langerhans. These islets have an irregular arrangement of cells, β cells that secrete insulin, α cells that secrete glucagon, and other cells with less well-understood functions. While the arrangement of β cells is irregular, these cells need to be touching for the islet to respond to glucose with insulin secretion. We first use a mathematical formalism called graph theory to show that cell arrangements in islets from diabetic and control donors are significantly different. The question we then address is: Is there some set of moves of islet cells that will preserve the observed arrangement? The aim is to gain insight into the biological processes by which islets are formed and maintained. We find moves on β-cell graphs that leave the same significant aspects of cell arrangements unchanged. These moves turn out to be severely restricted, and suggest that β cells may prefer to move from larger clusters but can move to a cluster of any size, possibly to maximize their exposure to blood vessels.
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Affiliation(s)
- Deborah A. Striegel
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Manami Hara
- Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Vipul Periwal
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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24
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Spijker HS, Song H, Ellenbroek JH, Roefs MM, Engelse MA, Bos E, Koster AJ, Rabelink TJ, Hansen BC, Clark A, Carlotti F, de Koning EJP. Loss of β-Cell Identity Occurs in Type 2 Diabetes and Is Associated With Islet Amyloid Deposits. Diabetes 2015; 64:2928-38. [PMID: 25918235 DOI: 10.2337/db14-1752] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 04/10/2015] [Indexed: 01/06/2023]
Abstract
Loss of pancreatic islet β-cell mass and β-cell dysfunction are central in the development of type 2 diabetes (T2DM). We recently showed that mature human insulin-containing β-cells can convert into glucagon-containing α-cells ex vivo. This loss of β-cell identity was characterized by the presence of β-cell transcription factors (Nkx6.1, Pdx1) in glucagon(+) cells. Here, we investigated whether the loss of β-cell identity also occurs in vivo, and whether it is related to the presence of (pre)diabetes in humans and nonhuman primates. We observed an eight times increased frequency of insulin(+) cells coexpressing glucagon in donors with diabetes. Up to 5% of the cells that were Nkx6.1(+) but insulin(-) coexpressed glucagon, which represents a five times increased frequency compared with the control group. This increase in bihormonal and Nkx6.1(+)glucagon(+)insulin(-) cells was also found in islets of diabetic macaques. The higher proportion of bihormonal cells and Nkx6.1(+)glucagon(+)insulin(-) cells in macaques and humans with diabetes was correlated with the presence and extent of islet amyloidosis. These data indicate that the loss of β-cell identity occurs in T2DM and could contribute to the decrease of functional β-cell mass. Maintenance of β-cell identity is a potential novel strategy to preserve β-cell function in diabetes.
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Affiliation(s)
- H Siebe Spijker
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Heein Song
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Johanne H Ellenbroek
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Maaike M Roefs
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Marten A Engelse
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Erik Bos
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Abraham J Koster
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Ton J Rabelink
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Barbara C Hansen
- Departments of Internal Medicine and Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Anne Clark
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Churchill Hospital, Oxford, U.K
| | - Françoise Carlotti
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Eelco J P de Koning
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands Hubrecht Institute, Utrecht, the Netherlands
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25
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Guardado Mendoza R, Perego C, Finzi G, La Rosa S, Capella C, Jimenez-Ceja LM, Velloso LA, Saad MJA, Sessa F, Bertuzzi F, Moretti S, Dick EJ, Davalli AM, Folli F. Delta cell death in the islet of Langerhans and the progression from normal glucose tolerance to type 2 diabetes in non-human primates (baboon, Papio hamadryas). Diabetologia 2015; 58:1814-26. [PMID: 26049399 PMCID: PMC5603258 DOI: 10.1007/s00125-015-3625-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 04/21/2015] [Indexed: 12/16/2022]
Abstract
AIMS/HYPOTHESIS The cellular composition of the islet of Langerhans is essential to ensure its physiological function. Morphophysiological islet abnormalities are present in type 2 diabetes but the relationship between fasting plasma glucose (FPG) and islet cell composition, particularly the role of delta cells, is unknown. We explored these questions in pancreases from baboons (Papio hamadryas) with FPG ranging from normal to type 2 diabetic values. METHODS We measured the volumes of alpha, beta and delta cells and amyloid in pancreatic islets of 40 baboons (Group 1 [G1]: FPG < 4.44 mmol/l [n = 10]; G2: FPG = 4.44-5.26 mmol/l [n = 9]; G3: FPG = 5.27-6.94 mmol/l [n = 9]; G4: FPG > 6.94 mmol/l [n = 12]) and correlated islet composition with metabolic and hormonal variables. We also performed confocal microscopy including TUNEL, caspase-3, and anti-caspase cleavage product of cytokeratin 18 (M30) immunostaining, electron microscopy, and immuno-electron microscopy with anti-somatostatin antibodies in baboon pancreases. RESULTS Amyloidosis preceded the decrease in beta cell volume. Alpha cell volume increased ∼ 50% in G3 and G4 (p < 0.05), while delta cell volume decreased in these groups by 31% and 39%, respectively (p < 0.05). In G4, glucagon levels were higher, while insulin and HOMA index of beta cell function were lower than in the other groups. Immunostaining of G4 pancreatic sections with TUNEL, caspase-3 and M30 showed apoptosis of beta and delta cells, which was also confirmed by immuno-electron microscopy with anti-somatostatin antibodies. CONCLUSIONS/INTERPRETATION In diabetic baboons, changes in islet composition correlate with amyloid deposition, with increased alpha cell and decreased beta and delta cell volume and number due to apoptosis. These data argue for an important role of delta cells in type 2 diabetes.
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Affiliation(s)
- Rodolfo Guardado Mendoza
- Department of Medicine, Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229-3900, USA
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26
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Colegrove KM, Venn-Watson S. Histomorphology of the bottlenose dolphin (Tursiops truncatus) pancreas and association of increasing islet β-cell size with chronic hypercholesterolemia. Gen Comp Endocrinol 2015; 214:17-23. [PMID: 25745813 DOI: 10.1016/j.ygcen.2015.02.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 12/12/2014] [Accepted: 02/14/2015] [Indexed: 01/09/2023]
Abstract
Bottlenose dolphins (Tursiops truncatus) can develop metabolic states mimicking prediabetes, including hyperinsulinemia, hyperlipidemia, elevated glucose, and fatty liver disease. Little is known, however, about dolphin pancreatic histomorphology. Distribution and area of islets, α, β, and δ cells were evaluated in pancreatic tissue from 22 dolphins (mean age 25.7years, range 0-51). Associations of these measurements were evaluated by sex, age, percent high glucose and lipids during the last year of life, and presence or absence of fatty liver disease and islet cell vacuolation. The most common pancreatic lesions identified were exocrine pancreas fibrosis (63.6%) and mild islet cell vacuolation (47.4%); there was no evidence of insulitis or amyloid deposition, changes commonly associated with type 2 diabetes. Dolphin islet architecture appears to be most similar to the pig, where α and β cells are localized to the central or periphery of the islet, respectively, or are well dispersed throughout the islet. Unlike pigs, large islets (greater than 10,000μm(2)) were common in dolphins, similar to that found in humans. A positive linear association was identified between dolphin age and islet area average, supporting a compensatory response similar to other species. The strongest finding in this study was a positive linear association between islet size, specifically β-cells, and percent blood samples with high cholesterol (greater than 280mg/dl, R(2)=0.57). This study is the most comprehensive assessment of the dolphin pancreas to date and may help direct future studies, including associations between chronic hypercholesterolemia and β-cell size.
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Affiliation(s)
- Kathleen M Colegrove
- Zoological Pathology Program, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, LUMC, Building 101, Room 0745, Maywood, IL 60153, USA.
| | - Stephanie Venn-Watson
- Translational Medicine and Research Program, National Marine Mammal Foundation, 2240 Shelter Island Suite 200, San Diego, CA 92106, USA.
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Javeed N, Sagar G, Dutta SK, Smyrk TC, Lau JS, Bhattacharya S, Truty M, Petersen GM, Kaufman RJ, Chari ST, Mukhopadhyay D. Pancreatic Cancer-Derived Exosomes Cause Paraneoplastic β-cell Dysfunction. Clin Cancer Res 2015; 21:1722-33. [PMID: 25355928 PMCID: PMC4383684 DOI: 10.1158/1078-0432.ccr-14-2022] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 10/11/2014] [Indexed: 12/14/2022]
Abstract
PURPOSE Pancreatic cancer frequently causes diabetes. We recently proposed adrenomedullin as a candidate mediator of pancreatic β-cell dysfunction in pancreatic cancer. How pancreatic cancer-derived adrenomedullin reaches β cells remote from the cancer to induce β-cell dysfunction is unknown. We tested a novel hypothesis that pancreatic cancer sheds adrenomedullin-containing exosomes into circulation, which are transported to β cells and impair insulin secretion. EXPERIMENTAL METHODS We characterized exosomes from conditioned media of pancreatic cancer cell lines (n = 5) and portal/peripheral venous blood of patients with pancreatic cancer (n = 20). Western blot analysis showed the presence of adrenomedullin in pancreatic cancer-exosomes. We determined the effect of adrenomedullin-containing pancreatic cancer exosomes on insulin secretion from INS-1 β cells and human islets, and demonstrated the mechanism of exosome internalization into β cells. We studied the interaction between β-cell adrenomedullin receptors and adrenomedullin present in pancreatic cancer-exosomes. In addition, the effect of adrenomedullin on endoplasmic reticulum (ER) stress response genes and reactive oxygen/nitrogen species generation in β cells was shown. RESULTS Exosomes were found to be the predominant extracellular vesicles secreted by pancreatic cancer into culture media and patient plasma. Pancreatic cancer-exosomes contained adrenomedullin and CA19-9, readily entered β cells through caveolin-mediated endocytosis or macropinocytosis, and inhibited insulin secretion. Adrenomedullin in pancreatic cancer exosomes interacted with its receptor on β cells. Adrenomedullin receptor blockade abrogated the inhibitory effect of exosomes on insulin secretion. β cells exposed to adrenomedullin or pancreatic cancer exosomes showed upregulation of ER stress genes and increased reactive oxygen/nitrogen species. CONCLUSIONS Pancreatic cancer causes paraneoplastic β-cell dysfunction by shedding adrenomedullin(+)/CA19-9(+) exosomes into circulation that inhibit insulin secretion, likely through adrenomedullin-induced ER stress and failure of the unfolded protein response.
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Affiliation(s)
- Naureen Javeed
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Gunisha Sagar
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Shamit K Dutta
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Thomas C Smyrk
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Julie S Lau
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Santanu Bhattacharya
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Mark Truty
- Department of Surgery, Mayo Clinic, Rochester, Minnesota
| | - Gloria M Petersen
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | - Randal J Kaufman
- Degenerative Disease Research Program, Sanford Burnham Medical Research Institute, La Jolla, California
| | - Suresh T Chari
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota.
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28
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Javeed N, Sagar G, Dutta SK, Smyrk TC, Lau JS, Bhattacharya S, Truty M, Petersen GM, Kaufman RJ, Chari ST, Mukhopadhyay D. Pancreatic Cancer-Derived Exosomes Cause Paraneoplastic β-cell Dysfunction. Clin Cancer Res 2014. [PMID: 25355928 DOI: 10.1158/1078-0432.ccr-14-2022.pancreatic] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
PURPOSE Pancreatic cancer frequently causes diabetes. We recently proposed adrenomedullin as a candidate mediator of pancreatic β-cell dysfunction in pancreatic cancer. How pancreatic cancer-derived adrenomedullin reaches β cells remote from the cancer to induce β-cell dysfunction is unknown. We tested a novel hypothesis that pancreatic cancer sheds adrenomedullin-containing exosomes into circulation, which are transported to β cells and impair insulin secretion. EXPERIMENTAL METHODS We characterized exosomes from conditioned media of pancreatic cancer cell lines (n = 5) and portal/peripheral venous blood of patients with pancreatic cancer (n = 20). Western blot analysis showed the presence of adrenomedullin in pancreatic cancer-exosomes. We determined the effect of adrenomedullin-containing pancreatic cancer exosomes on insulin secretion from INS-1 β cells and human islets, and demonstrated the mechanism of exosome internalization into β cells. We studied the interaction between β-cell adrenomedullin receptors and adrenomedullin present in pancreatic cancer-exosomes. In addition, the effect of adrenomedullin on endoplasmic reticulum (ER) stress response genes and reactive oxygen/nitrogen species generation in β cells was shown. RESULTS Exosomes were found to be the predominant extracellular vesicles secreted by pancreatic cancer into culture media and patient plasma. Pancreatic cancer-exosomes contained adrenomedullin and CA19-9, readily entered β cells through caveolin-mediated endocytosis or macropinocytosis, and inhibited insulin secretion. Adrenomedullin in pancreatic cancer exosomes interacted with its receptor on β cells. Adrenomedullin receptor blockade abrogated the inhibitory effect of exosomes on insulin secretion. β cells exposed to adrenomedullin or pancreatic cancer exosomes showed upregulation of ER stress genes and increased reactive oxygen/nitrogen species. CONCLUSIONS Pancreatic cancer causes paraneoplastic β-cell dysfunction by shedding adrenomedullin(+)/CA19-9(+) exosomes into circulation that inhibit insulin secretion, likely through adrenomedullin-induced ER stress and failure of the unfolded protein response.
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Affiliation(s)
- Naureen Javeed
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Gunisha Sagar
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Shamit K Dutta
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Thomas C Smyrk
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Julie S Lau
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Santanu Bhattacharya
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Mark Truty
- Department of Surgery, Mayo Clinic, Rochester, Minnesota
| | - Gloria M Petersen
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | - Randal J Kaufman
- Degenerative Disease Research Program, Sanford Burnham Medical Research Institute, La Jolla, California
| | - Suresh T Chari
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota.
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29
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Hoang DT, Matsunari H, Nagaya M, Nagashima H, Millis JM, Witkowski P, Periwal V, Hara M, Jo J. A conserved rule for pancreatic islet organization. PLoS One 2014; 9:e110384. [PMID: 25350558 PMCID: PMC4211668 DOI: 10.1371/journal.pone.0110384] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/12/2014] [Indexed: 11/18/2022] Open
Abstract
Morphogenesis, spontaneous formation of organism structure, is essential for life. In the pancreas, endocrine , , and cells are clustered to form islets of Langerhans, the critical micro-organ for glucose homeostasis. The spatial organization of endocrine cells in islets looks different between species. Based on the three-dimensional positions of individual cells in islets, we computationally inferred the relative attractions between cell types, and found that the attractions between homotypic cells were slightly, but significantly, stronger than the attractions between heterotypic cells commonly in mouse, pig, and human islets. The difference between cell attraction and cell attraction was minimal in human islets, maximizing the plasticity of islet structures. Our result suggests that although the cellular composition and attractions of pancreatic endocrine cells are quantitatively different between species, the physical mechanism of islet morphogenesis may be evolutionarily conserved.
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Affiliation(s)
- Danh-Tai Hoang
- Asia Pacific Center for Theoretical Physics, Pohang, Korea
| | - Hitomi Matsunari
- Meiji University International Institute for Bio-Resource Research, Kanagawa, Japan
| | - Masaki Nagaya
- Meiji University International Institute for Bio-Resource Research, Kanagawa, Japan
| | - Hiroshi Nagashima
- Meiji University International Institute for Bio-Resource Research, Kanagawa, Japan
| | - J. Michael Millis
- Department of Surgery, The University of Chicago, Chicago, IL, United States of America
| | - Piotr Witkowski
- Department of Surgery, The University of Chicago, Chicago, IL, United States of America
| | - Vipul Periwal
- Laboratory of Biological Modeling, NIDDK, NIH, Bethesda, MD, United States of America
| | - Manami Hara
- Department of Medicine, The University of Chicago, Chicago, IL, United States of America
- * E-mail: (MH); (JJ)
| | - Junghyo Jo
- Asia Pacific Center for Theoretical Physics, Pohang, Korea
- Department of Physics, POSTECH, Pohang, Korea
- * E-mail: (MH); (JJ)
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Halban PA, Polonsky KS, Bowden DW, Hawkins MA, Ling C, Mather KJ, Powers AC, Rhodes CJ, Sussel L, Weir GC. β-cell failure in type 2 diabetes: postulated mechanisms and prospects for prevention and treatment. J Clin Endocrinol Metab 2014; 99:1983-92. [PMID: 24712577 PMCID: PMC5393482 DOI: 10.1210/jc.2014-1425] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE This article examines the foundation of β-cell failure in type 2 diabetes (T2D) and suggests areas for future research on the underlying mechanisms that may lead to improved prevention and treatment. RESEARCH DESIGN AND METHODS A group of experts participated in a conference on 14-16 October 2013 cosponsored by the Endocrine Society and the American Diabetes Association. A writing group prepared this summary and recommendations. RESULTS The writing group based this article on conference presentations, discussion, and debate. Topics covered include genetic predisposition, foundations of β-cell failure, natural history of β-cell failure, and impact of therapeutic interventions. CONCLUSIONS β-Cell failure is central to the development and progression of T2D. It antedates and predicts diabetes onset and progression, is in part genetically determined, and often can be identified with accuracy even though current tests are cumbersome and not well standardized. Multiple pathways underlie decreased β-cell function and mass, some of which may be shared and may also be a consequence of processes that initially caused dysfunction. Goals for future research include to 1) impact the natural history of β-cell failure; 2) identify and characterize genetic loci for T2D; 3) target β-cell signaling, metabolic, and genetic pathways to improve function/mass; 4) develop alternative sources of β-cells for cell-based therapy; 5) focus on metabolic environment to provide indirect benefit to β-cells; 6) improve understanding of the physiology of responses to bypass surgery; and 7) identify circulating factors and neuronal circuits underlying the axis of communication between the brain and β-cells.
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31
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Halban PA, Polonsky KS, Bowden DW, Hawkins MA, Ling C, Mather KJ, Powers AC, Rhodes CJ, Sussel L, Weir GC. β-cell failure in type 2 diabetes: postulated mechanisms and prospects for prevention and treatment. Diabetes Care 2014; 37:1751-8. [PMID: 24812433 PMCID: PMC4179518 DOI: 10.2337/dc14-0396] [Citation(s) in RCA: 329] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE This article examines the foundation of β-cell failure in type 2 diabetes (T2D) and suggests areas for future research on the underlying mechanisms that may lead to improved prevention and treatment. RESEARCH DESIGN AND METHODS A group of experts participated in a conference on 14-16 October 2013 cosponsored by the Endocrine Society and the American Diabetes Association. A writing group prepared this summary and recommendations. RESULTS The writing group based this article on conference presentations, discussion, and debate. Topics covered include genetic predisposition, foundations of β-cell failure, natural history of β-cell failure, and impact of therapeutic interventions. CONCLUSIONS β-Cell failure is central to the development and progression of T2D. It antedates and predicts diabetes onset and progression, is in part genetically determined, and often can be identified with accuracy even though current tests are cumbersome and not well standardized. Multiple pathways underlie decreased β-cell function and mass, some of which may be shared and may also be a consequence of processes that initially caused dysfunction. Goals for future research include to (1) impact the natural history of β-cell failure; (2) identify and characterize genetic loci for T2D; (3) target β-cell signaling, metabolic, and genetic pathways to improve function/mass; (4) develop alternative sources of β-cells for cell-based therapy; (5) focus on metabolic environment to provide indirect benefit to β-cells; (6) improve understanding of the physiology of responses to bypass surgery; and (7) identify circulating factors and neuronal circuits underlying the axis of communication between the brain and β-cells.
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Affiliation(s)
- Philippe A Halban
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
| | - Kenneth S Polonsky
- Department of Medicine, Section of Endocrinology, University of Chicago, Chicago, IL
| | - Donald W Bowden
- Center for Genomics and Personalized Medicine Research and Center for Diabetes Research, Wake Forest University, Winston-Salem, NC
| | - Meredith A Hawkins
- Department of Medicine (Endocrinology) and Global Diabetes Institute, Albert Einstein College of Medicine, Bronx, NY
| | - Charlotte Ling
- Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kieren J Mather
- Department of Endocrinology, Indiana University, Indianapolis, IN
| | - Alvin C Powers
- Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University School of Medicine, Nashville, TN
| | - Christopher J Rhodes
- Kovler Diabetes Center, Department of Medicine, University of Chicago, Chicago, IL
| | - Lori Sussel
- Naomi Berrie Diabetes Center, Columbia University, New York, NY
| | - Gordon C Weir
- Joslin Diabetes Center, Harvard Medical School, Boston, MA
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32
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Liu XD, Ruan JX, Xia JH, Yang SL, Fan JH, Li K. The study of regulatory effects of Pdx-1, MafA and NeuroD1 on the activity of porcine insulin promoter and the expression of human islet amyloid polypeptide. Mol Cell Biochem 2014; 394:59-66. [DOI: 10.1007/s11010-014-2081-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 05/03/2014] [Indexed: 10/25/2022]
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Levetan CS, Pierce SM. Distinctions between the islets of mice and men: implications for new therapies for type 1 and 2 diabetes. Endocr Pract 2013. [PMID: 23186955 DOI: 10.4158/ep12138.ra] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To elucidate why diabetes is so difficult to treat despite the present tools and pharmacologic armamentarium and to provide insights into emerging therapies by describing human and rodent data that demonstrates the ability to transform progenitor cells within the adult pancreas into new islets. METHODS A literature review focused on the distinctions between human and rodent islets. RESULTS We are beginning to elucidate important differences between the architecture and composition of the islets of Langerhans in humans and rodents. In contrast to rodent islets, human islets are more heterogeneous in cellular composition and have more prominent intra-islet vascularity, with smooth muscle-containing blood vessels that are not present in rodent islets. Some studies report that more than 70% of human beta cells have direct physical contact with other cell types, whereas others describe that smaller human islets possess features more typical of rodents, while larger islets exhibit greater vascularity and a cellular distribution distinct from centrally clustered beta cells surrounded by a mantle of alpha and delta cells found in rodents. CONCLUSIONS The differences between the islets of mice and men may influence why treatments hailed as reversing diabetes among rodents have not been successfully translated into humans. Increased understanding of the complexities within the human islet may yield unique insights into reversing diabetes in humans.
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Affiliation(s)
- Claresa S Levetan
- Division of Diabetes, Endocrinology and Metabolism, Chestnut Hill Hospital, Philadelphia, PA 19118, USA.
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Schmidt S, Jakab M, Jav S, Streif D, Pitschmann A, Zehl M, Purevsuren S, Glasl S, Ritter M. Extracts from Leonurus sibiricus L. increase insulin secretion and proliferation of rat INS-1E insulinoma cells. JOURNAL OF ETHNOPHARMACOLOGY 2013; 150:85-94. [PMID: 23978659 DOI: 10.1016/j.jep.2013.08.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 08/02/2013] [Accepted: 08/03/2013] [Indexed: 06/02/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Traditional Mongolian medicine (TMM) uses preparations from herbs as one form of medication for the treatment of a diversity of diseases including diabetes mellitus (DM). We evaluated the effect of extracts from the plant Leonurus sibiricus L. (LS), used in TMM to treat typical symptoms of type 2 DM, on insulin secretion, electrophysiological properties, intracellular calcium concentration and cell proliferation of INS-1E insulinoma cells under standard cell culture conditions (SCC; 11.1mM glucose). MATERIALS AND METHODS Insulin secretion was measured by ELISA, electrical properties were assessed by whole cell patch clamping, intracellular calcium concentration (Cai) by Fluo-4 time lapse imaging, insulin receptor expression was verified by RT-PCR and cell proliferation assessed by CellTiter-Glo® cell viability assay. RESULTS Insulin released from INS-1E cells into the culture medium over 24h was significantly increased in presence of 500 mg/L aqueous LS extract (LS OWE) as well as methanolic LS extract (LS MeOH/H2O) but not in the presence of the butanol-soluble extract (LS MeOH/BuOH). Acute application of LS OWE resulted in a depolarization of the cell membrane potential paralleled by an initial increase and subsequent decline and silencing of action potential frequency, by KATP channel inhibition, persisting depolarization and an increase in Cai. The electrophysiological effects were comparable to those of 100 μM tolbutamide, which, however failed to elevate insulin secretion under SCC. Furthermore all LS extracts stimulated INS-1E cell proliferation. CONCLUSIONS The finding that extracts from Leonurus sibiricus L. enhance insulin secretion and/or foster cell proliferation may provide possible explanations for the underlying therapeutic principles in the empirical use of LS-containing formulations in DM and DM-related disorders as applied in TMM.
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Affiliation(s)
- S Schmidt
- Institute of Physiology and Pathophysiology, Paracelsus Medical University Salzburg, 5020 Salzburg, Austria.
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Caicedo A. Paracrine and autocrine interactions in the human islet: more than meets the eye. Semin Cell Dev Biol 2012; 24:11-21. [PMID: 23022232 DOI: 10.1016/j.semcdb.2012.09.007] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 09/19/2012] [Indexed: 12/20/2022]
Abstract
The pancreatic islet secretes the hormones insulin and glucagon to regulate glucose metabolism. To generate an adequate secretory response, islet endocrine cells must receive multiple regulatory signals relaying information about changes in the internal and external environments. Islet cells also need to be made aware about the functional status of neighboring cells through paracrine interactions. All this information is used to orchestrate a hormonal response that contributes to glucose homeostasis. Several neurotransmitters have been proposed to work as paracrine signals in the islet. Most of these, however, have yet to meet the criteria to be considered bona fide paracrine signals, in particular in human islets. Here, we review recent findings describing autocrine and paracrine signaling mechanisms in human islets. These recent results are showing an increasingly complex picture of paracrine interactions in the human islet and emphasize that results from other species cannot be readily extrapolated to the human context. Investigators are unveiling new signaling mechanisms or finding new roles for known paracrine signals in human islets. While it is too early to provide a synthesis, the field of islet research is defining the paracrine and autocrine components that will be used to generate models about how islet function is regulated. Meanwhile, the identified signaling pathways can be proposed as therapeutic targets for treating diabetes, a devastating disease affecting millions worldwide.
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Affiliation(s)
- Alejandro Caicedo
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA.
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Thole A, Rodrigues-Cunha A, Carvalho S, Garcia-Souza E, Cortez E, Stumbo A, Carvalho L, Moura A. Progenitor cells and TNF-alpha involvement during morphological changes in pancreatic islets of obese mice. Tissue Cell 2012; 44:238-48. [DOI: 10.1016/j.tice.2012.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 03/30/2012] [Accepted: 04/02/2012] [Indexed: 12/28/2022]
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Santos-Silva JC, Carvalho CPDF, de Oliveira RB, Boschero AC, Collares-Buzato CB. Cell-to-cell contact dependence and junctional protein content are correlated with in vivo maturation of pancreatic beta cells. Can J Physiol Pharmacol 2012; 90:837-50. [DOI: 10.1139/y2012-064] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In this study, we investigated the cellular distribution of junctional proteins and the dependence on cell–cell contacts of pancreatic beta cells during animal development. Fetus and newborn rat islets, which display a relatively poor insulin secretory response to glucose, present an immature morphology and cytoarchitecture when compared with young and adult islets that are responsive to glucose. At the perinatal stage, beta cells display a low junctional content of neural cell adhesion molecule (N-CAM), α- and β-catenins, ZO-1, and F-actin, while a differential distribution of N-CAM and Pan-cadherin was seen in beta cells and nonbeta cells only from young and adult islets. In the absence of intercellular contacts, the glucose-stimulated insulin secretion was completely blocked in adult beta cells, but after reaggregation they partially reestablished the secretory response to glucose. By contrast, neonatal beta cells were poorly responsive to sugar, regardless of whether they were arranged as intact islets or as isolated cells. Interestingly, after 10 days of culturing, neonatal beta cells, known to display increased junctional protein content in vitro, became responsive to glucose and concomitantly dependent on cell–cell contacts. Therefore, our data suggest that the developmental acquisition of an adult-like insulin secretory pattern is paralleled by a dependence on direct cell–cell interactions.
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Affiliation(s)
- Junia Carolina Santos-Silva
- Department of Histology and Embryology, Institute of Biology, University of Campinas (UNICAMP), Campinas CEP 13083-970, São Paulo, Brazil
| | - Carolina Prado de França Carvalho
- Department of Histology and Embryology, Institute of Biology, University of Campinas (UNICAMP), Campinas CEP 13083-970, São Paulo, Brazil
| | - Ricardo Beltrame de Oliveira
- Department of Histology and Embryology, Institute of Biology, University of Campinas (UNICAMP), Campinas CEP 13083-970, São Paulo, Brazil
| | - Antonio Carlos Boschero
- Department of Anatomy, Cell Biology and Physiology and Biophysics, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Carla Beatriz Collares-Buzato
- Department of Histology and Embryology, Institute of Biology, University of Campinas (UNICAMP), Campinas CEP 13083-970, São Paulo, Brazil
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Abstract
AIMS/HYPOTHESIS Islet amyloid polypeptide (IAPP) is a chief constituent of amyloid deposits in pancreatic islets, characteristic histopathology for type 2 diabetes. The goal of this study was to analyze islet cell composition in diabetic islets for the process of transforming water-soluble IAPP in β-cells to water-insoluble amyloid deposits by Immunocytochemical staining using different dilutions of anti-IAPP antibody. IAPP in β-cell granules may initiate β-cell necrosis through apoptosis to form interstitial amyloid deposits in type 2 diabetic islets. RESULTS Control islets revealed twice as much β-cells as α-cells whereas 15 of 18 type 2 diabetic cases (83%) revealed α- cells as major cells in larger islets. Diabetic islets consisted of more larger islets with more σ-cells than β-cells, which contribute to hyperglucagonemia. In control islets, percentage of IAPP-positive cells against β-cells was 40-50% whereas percentage for type 2 diabetic islets was about 25%. Amyloid deposits in diabetic islets were not readily immunostained for IAPP using 1: 800 diluted antibody, however, 1: 400 and 1: 200 diluted solutions provided stronger immunostaining in early stages of islet amyloidogenesis after treating the deparaffinized sections with formic acid. METHODS Using commercially available rabbit antihuman IAPP antibody, immunocytochemical staining was performed on 18 cases of pancreatic tissues from type 2 diabetic subjects by systematically immunostaining for insulin, glucagon, somatostatin (SRIF) and IAPP compared with controls. Sizes of islets were measured by 1 cm scale, mounted in 10X eye piece. CONCLUSIONS/INTERPRETATION α cells were major islet cells in majority of diabetic pancreas (83%) and all diabetic islets contained less IAPP-positive cells than controls, indicating that IAPP deficiency in pancreatic islets is responsible for decreased IAPP in blood. In diabetic islets, water-soluble IAPP disappeared in β-cell granules, which transformed to water-insoluble amyloid deposits. Amyloid deposits were not readily immunostained using IAPP 1: 800 diluted antibody but were stronger immunostained for IAPP in early stages of amyloid deposited islets using less diluted solutions after formic acid treatment. In early islet amyloidogenesis, dying β-cell cytoplasm was adjacently located to fine amyloid fibrils, supporting that IAPP in secretary granules from dying β cells served as nidus for islet β-sheet formation.
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Affiliation(s)
- Tatsuo Tomita
- Department of Integrative Bioscience, Oregon National Primate Center, Oregon Health and Science University, Portland, OR, USA.
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Liu C, Koeberlein B, Feldman MD, Mueller R, Wang Z, Li Y, Lane K, Hoyt CC, Tomaszewski JE, Naji A, Rickels MR. Accumulation of intrahepatic islet amyloid in a nonhuman primate transplant model. Endocrinology 2012; 153:1673-83. [PMID: 22355065 PMCID: PMC3320262 DOI: 10.1210/en.2011-1560] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Islet amyloid is hypothesized to play a role in nonimmunologic transplanted islet graft loss. We performed a quantitative histologic analysis of liver biopsies from intrahepatic islet grafts transplanted in streptozotocin-induced diabetic cynomolgus macaques. Seven animals treated with antithymocyte globulin (ATG) and rapamycin or ATG and rituximab experienced islet graft rejection with lymphocytic infiltrates present on islet graft biopsies. Except for one case involving the oldest and largest donor where amyloid was present on initial biopsy 1 month after transplant, none of the six other cases with rejection contained amyloid, including one case biopsied serially to 25 months. In contrast, four out of six animals treated with ATG and rituximab and rapamycin had no evidence of rejection at the time of biopsy (two animals that discontinued rapamycin had mild periislet lymphocytes), and all four cases followed more than 4 months demonstrated amyloid deposition at subsequent time points. Amyloid severity increased with time after transplant (r = 0.68; P < 0.05) and with decreasing islet β-cell area (r = -0.68; P < 0.05). In two islet recipients with no evidence of rejection and still normoglycemic and insulin independent at the first detection of amyloid, β-cell secretory capacity declined over time coincident with increasing amyloid severity and decreasing β-cell area, with both animals eventually becoming hyperglycemic and insulin dependent. Transplanted islet amyloid also developed in autologous islets placed sc. These results indicate that in cynomolgus macaques, transplanted islets may accumulate amyloid over time associated with subsequent decline in β-cell mass and function and support the development of intrahepatic islet amyloid as a potential mechanism for nonimmunologic islet graft loss.
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Affiliation(s)
- Chengyang Liu
- Division of Transplantation, Department of Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104-5160, USA
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Kawamori D, Akiyama M, Hu J, Hambro B, Kulkarni RN. Growth factor signalling in the regulation of α-cell fate. Diabetes Obes Metab 2011; 13 Suppl 1:21-30. [PMID: 21824253 DOI: 10.1111/j.1463-1326.2011.01442.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Glucagon plays critical roles in regulating glucose homeostasis, mainly by counteracting the effects of insulin. Consequently, the dysregulated glucagon secretion that is evident in type 2 diabetes has significant implications in the pathophysiology of the disease. Glucagon secretion from pancreatic α-cells has been suggested to be modulated by blood glucose, signals from the nervous system and endocrine components. In addition to these regulators, intraislet factors acting in a paracrine manner from neighbouring β-cells are emerging as central modulator(s) of α-cell biology. One of the most important of these paracrine factors, insulin, modulates glucagon secretion. Indeed, the α-cell-specific insulin receptor knockout (αIRKO) mouse manifests hypersecretion of glucagon in the postprandial stage and exhibits defective secretion in fasting-induced hypoglycaemia, together mimicking the α-cell defects observed in type 2 diabetes. Interestingly, αIRKO mice display a progressive increase in β-cell mass and a concomitant decrease in α-cells. Lineage trace analyses reveal that the new β-cells originate, in part, from the insulin receptor-deficient α-cells indicating a critical role for α-cell insulin signalling in determining β-cell origin. Our studies also reveal that glucagon-like peptide-1 (GLP-1) treatment of αIRKO mice suppresses glucagon secretion despite absence of functional insulin receptors precluding a role for insulin in GLP-1 action on α-cells in this model. These findings highlight the significance of insulin signalling in the regulation of α-cell biology.
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Affiliation(s)
- D Kawamori
- Section of Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA.
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41
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van Raalte DH, Diamant M. Glucolipotoxicity and beta cells in type 2 diabetes mellitus: target for durable therapy? Diabetes Res Clin Pract 2011; 93 Suppl 1:S37-46. [PMID: 21864750 DOI: 10.1016/s0168-8227(11)70012-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Type 2 diabetes mellitus (T2DM) is characterised by beta-cell failure in the setting of obesity-related insulin resistance. Progressive beta-cell dysfunction determines the course of the disease, regardless of the treatment used. There is mounting evidence that chronically elevated circulating levels of glucose and fatty acids contribute to relentless beta-cell function decline, by endorsing processes commonly referred to as glucolipotoxicity. Mechanisms related to glucolipotoxicity include endoplasmic reticulum (ER) stress, oxidative stress, mitochondrial dysfunction and islet inflammation. The most commonly prescribed blood-glucose lowering agents, metformin and sul-fonylurea, may temporarily improve glycaemic control, however, these drugs do not alter the continuous decline in beta-cell function in T2DM patients. Evidence exists that novel classes of drugs, the thiazolidinediones (TZDs) and incretin-based therapies, may be able to preserve beta-cell function and functional beta-cell mass, amongst others by reducing glucolipotoxicity in the beta cell. The durability of the effects of TZDs and incretin-based therapies on beta-cell function, whether given as monotherapy or combined with other treatment, should be addressed in future, long-term clinical studies.
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Affiliation(s)
- Daniel H van Raalte
- Diabetes Centre, Department of Internal Medicine, VU University Medical Centre, Amsterdam, The Netherlands.
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42
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Henson MS, Hegstad-Davies RL, Wang Q, Hardy RM, Armstrong PJ, Jordan K, Johnson KH, O'Brien TD. Evaluation of plasma islet amyloid polypeptide and serum glucose and insulin concentrations in nondiabetic cats classified by body condition score and in cats with naturally occurring diabetes mellitus. Am J Vet Res 2011; 72:1052-8. [DOI: 10.2460/ajvr.72.8.1052] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Meng F, Raleigh DP. Inhibition of glycosaminoglycan-mediated amyloid formation by islet amyloid polypeptide and proIAPP processing intermediates. J Mol Biol 2010; 406:491-502. [PMID: 21195086 DOI: 10.1016/j.jmb.2010.12.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 12/14/2010] [Accepted: 12/20/2010] [Indexed: 02/07/2023]
Abstract
Islet amyloid polypeptide (IAPP; also known as amylin) is responsible for islet amyloid formation in type 2 diabetes, and IAPP-induced toxicity is believed to contribute to the loss of β-cell mass associated with the late stages of type 2 diabetes. Islet amyloid formation may also play a role in graft failure after transplantation. IAPP is produced as a prohormone, pro-islet amyloid polypeptide (proIAPP), and processed in the secretory granules of the pancreatic β-cells. Partially processed forms of proIAPP are found in amyloid deposits; most notable is a 48-residue intermediate, proIAPP(1-48), which includes the N-terminal pro-extension, but which has been properly processed at the C-terminus. Incomplete processing may play a role in islet amyloid formation by promoting interactions with sulfated proteoglycans of the extracellular matrix, which, in turn, promote amyloid formation. We show that acid fuchsin (3-(1-(4-amino-3-methyl-5-sulphonatophenyl)-1-(4-amino-3-sulphonatophenyl)methylene)cyclohexa-1,4-dienesulphonic acid), a simple sulfonated triphenyl methyl derivative, is a potent inhibitor of amyloid formation by the proIAPP(1-48) intermediate. The more complicated triphenyl methane derivative fast green FCF {ethyl-[4-[[4-[ethyl-[(3-sulfophenyl)methyl]amino]phenyl]-(4-hydroxy-2-sulfophenyl)methylidene]-1-cyclohexa-2,5-dienylidene]-[(3-sulfophenyl)methyl]azanium} also inhibits amyloid formation by IAPP and the proIAPP processing intermediate. Both compounds inhibit amyloid formation by mixtures of the proIAPP intermediate and the model glycosaminoglycan heparan sulfate. Acid fuchsin also inhibits glycosaminoglycan-mediated amyloid formation by mature IAPP. The ability to inhibit amyloid formation is not simply due to the compounds being sulfonated, since the sulfonated inhibitor of amyloid-β, tramiprosate, is not an inhibitor of amyloid formation by proIAPP(1-48).
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Affiliation(s)
- Fanling Meng
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
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44
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Christoffersson G, Henriksnäs J, Johansson L, Rolny C, Ahlström H, Caballero-Corbalan J, Segersvärd R, Permert J, Korsgren O, Carlsson PO, Phillipson M. Clinical and experimental pancreatic islet transplantation to striated muscle: establishment of a vascular system similar to that in native islets. Diabetes 2010; 59:2569-78. [PMID: 20651296 PMCID: PMC3279536 DOI: 10.2337/db10-0205] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Curing type 1 diabetes by transplanting pancreatic islets into the liver is associated with poor long-term outcome and graft failure at least partly due to inadequate graft revascularization. The aim of the current study was to evaluate striated muscle as a potential angiogenic site for islet transplantation. RESEARCH DESIGN AND METHODS The current study presents a new experimental model that is found to be applicable to clinical islet transplantation. Islets were implanted into striated muscle and intraislet vascular density and blood flow were visualized with intravital and confocal microscopy in mice and by magnetic resonance imaging in three autotransplanted pancreatectomized patients. Mice were rendered neutropenic by repeated injections of Gr-1 antibody, and diabetes was induced by alloxan treatment. RESULTS Contrary to liver-engrafted islets, islets transplanted to mouse muscle were revascularized with vessel densities and blood flow entirely comparable with those of islets within intact pancreas. Initiation of islet revascularization at the muscular site was dependent on neutrophils, and the function of islets transplanted to muscle was proven by curing diabetic mice. The experimental data were confirmed in autotransplanted patients where higher plasma volumes were measured in islets engrafted in forearm muscle compared with adjacent muscle tissue through high-resolution magnetic resonance imaging. CONCLUSIONS This study presents a novel paradigm in islet transplantation whereby recruited neutrophils are crucial for the functionally restored intraislet blood perfusion following transplantation to striated muscle under experimental and clinical situations.
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Affiliation(s)
| | | | - Lars Johansson
- Department of Oncology, Radiology and Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Charlotte Rolny
- Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Håkan Ahlström
- Department of Oncology, Radiology and Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - José Caballero-Corbalan
- Department of Oncology, Radiology and Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Ralf Segersvärd
- Department for Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
| | - Johan Permert
- Department for Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
| | - Olle Korsgren
- Department of Oncology, Radiology and Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Per-Ola Carlsson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Mia Phillipson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Corresponding author: Mia Phillipson,
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45
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Paracrinology of islets and the paracrinopathy of diabetes. Proc Natl Acad Sci U S A 2010; 107:16009-12. [PMID: 20798346 DOI: 10.1073/pnas.1006639107] [Citation(s) in RCA: 193] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
New results have brought to light the importance of the regulation of glucagon by β-cells in the development of diabetes. In this perspective, we examine the normal paracrinology of α- and β-cells in nondiabetic pancreatic islets. We propose a Sherringtonian model of coordinated reciprocal secretory responses of these juxtaposed cells that secrete glucagon and insulin, hormones with opposing actions on the liver. As insulin is a powerful inhibitor of glucagon, we propose that within-islet inhibition of α-cells by β-cells creates an insulin-to-glucagon ratio that maintains glycemic stability even in extremes of glucose influx or efflux. By contrast, in type 1 diabetes mellitus, α-cells lack constant action of high insulin levels from juxtaposed β-cells. Replacement with exogenous insulin does not approach paracrine levels of secreted insulin except with high doses that "overinsulinize" the peripheral insulin targets, thereby promoting glycemic volatility. Based on the stable normoglycemia of mice with type 1 diabetes during suppression of glucagon with leptin, we conclude that, in the absence of paracrine regulation of α-cells, tonic inhibition of α-cells improves the dysregulated glucose homeostasis. These results have considerable medical implications, as they suggest new approaches to normalize the extreme volatility of glycemia in diabetic patients.
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46
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Meng F, Abedini A, Plesner A, Middleton CT, Potter KJ, Zanni MT, Verchere CB, Raleigh DP. The sulfated triphenyl methane derivative acid fuchsin is a potent inhibitor of amyloid formation by human islet amyloid polypeptide and protects against the toxic effects of amyloid formation. J Mol Biol 2010; 400:555-66. [PMID: 20452363 DOI: 10.1016/j.jmb.2010.05.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 04/29/2010] [Accepted: 05/02/2010] [Indexed: 01/09/2023]
Abstract
Islet amyloid polypeptide (IAPP), also known as amylin, is responsible for amyloid formation in type 2 diabetes. The formation of islet amyloid is believed to contribute to the pathology of the disease by killing beta-cells, and it may also contribute to islet transplant failure. The design of inhibitors of amyloid formation is an active area of research, but comparatively little attention has been paid to inhibitors of IAPP in contrast to the large body of work on beta-amyloid, and most small-molecule inhibitors of IAPP amyloid are generally effective only when used at a significant molar excess. Here we show that the simple sulfonated triphenyl methane derivative acid fuchsin, 3-(1-(4-amino-3-methyl-5-sulfonatophenyl)-1-(4-amino-3-sulfonatophenyl) methylene) cyclohexa-1,4-dienesulfonic acid, is a potent inhibitor of in vitro amyloid formation by IAPP at substoichiometric levels and protects cultured rat INS-1 cells against the toxic effects of human IAPP. Fluorescence-detected thioflavin-T binding assays, light-scattering, circular dichroism, two-dimensional IR, and transmission electron microscopy measurements confirm that the compound prevents amyloid fibril formation. Ionic-strength-dependent studies show that the effects are mediated in part by electrostatic interactions. Experiments in which the compound is added at different time points during the lag phase after amyloid formation has commenced reveal that it arrests amyloid formation by trapping intermediate species. The compound is less effective against the beta-amyloid peptide, indicating specificity in its ability to inhibit amyloid formation by IAPP. The work reported here provides a new structural class of IAPP amyloid inhibitors and demonstrates the power of two-dimensional infrared spectroscopy for characterizing amyloid inhibitor interactions.
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Affiliation(s)
- Fanling Meng
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
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47
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Steiner DJ, Kim A, Miller K, Hara M. Pancreatic islet plasticity: interspecies comparison of islet architecture and composition. Islets 2010; 2:135-45. [PMID: 20657742 PMCID: PMC2908252 DOI: 10.4161/isl.2.3.11815] [Citation(s) in RCA: 303] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The pancreatic islet displays diverse patterns of endocrine cell arrangement. The prototypic islet, with insulin-secreting beta-cells forming the core surrounded by other endocrine cells in the periphery, is largely based on studies of normal rodent islets. Recent reports on large animals, including humans, show a difference in islet architecture, in which the endocrine cells are randomly distributed throughout the islet. This particular species difference has raised concerns regarding the interpretation of data based on rodent studies to humans. On the other hand, further variations have been reported in marsupials and some nonhuman primates, which possess an inverted ratio of beta-cells to other endocrine cells. This review discusses the striking plasticity of islet architecture and cellular composition among various species including changes in response to metabolic states within a single species. We propose that this plasticity reflects evolutionary acquired adaptation induced by altered physiological conditions, rather than inherent disparities between species.
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Affiliation(s)
| | - Abraham Kim
- Department of Medicine; The University of Chicago; Chicago, IL USA
| | - Kevin Miller
- Department of Medicine; The University of Chicago; Chicago, IL USA
| | - Manami Hara
- Department of Medicine; The University of Chicago; Chicago, IL USA
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48
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Bosco D, Armanet M, Morel P, Niclauss N, Sgroi A, Muller YD, Giovannoni L, Parnaud G, Berney T. Unique arrangement of alpha- and beta-cells in human islets of Langerhans. Diabetes 2010; 59:1202-10. [PMID: 20185817 PMCID: PMC2857900 DOI: 10.2337/db09-1177] [Citation(s) in RCA: 301] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE It is generally admitted that the endocrine cell organization in human islets is different from that of rodent islets. However, a clear description of human islet architecture has not yet been reported. The aim of this work was to describe our observations on the arrangement of human islet cells. RESEARCH DESIGN AND METHODS Human pancreas specimens and isolated islets were processed for histology. Sections were analyzed by fluorescence microscopy after immunostaining for islet hormones and endothelial cells. RESULTS In small human islets (40-60 mum in diameter), beta-cells had a core position, alpha-cells had a mantle position, and vessels laid at their periphery. In bigger islets, alpha-cells had a similar mantle position but were found also along vessels that penetrate and branch inside the islets. As a consequence of this organization, the ratio of beta-cells to alpha-cells was constantly higher in the core than in the mantle part of the islets, and decreased with increasing islet diameter. This core-mantle segregation of islet cells was also observed in type 2 diabetic donors but not in cultured isolated islets. Three-dimensional analysis revealed that islet cells were in fact organized into trilaminar epithelial plates, folded with different degrees of complexity and bordered by vessels on both sides. In epithelial plates, most beta-cells were located in a central position but frequently showed cytoplasmic extensions between outlying non-beta-cells. CONCLUSIONS Human islets have a unique architecture allowing all endocrine cells to be adjacent to blood vessels and favoring heterologous contacts between beta- and alpha-cells, while permitting homologous contacts between beta-cells.
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Affiliation(s)
- Domenico Bosco
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland.
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Kawamori D, Welters HJ, Kulkarni RN. Molecular Pathways Underlying the Pathogenesis of Pancreatic α-Cell Dysfunction. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 654:421-45. [DOI: 10.1007/978-90-481-3271-3_18] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Hellman B, Salehi A, Gylfe E, Dansk H, Grapengiesser E. Glucose generates coincident insulin and somatostatin pulses and antisynchronous glucagon pulses from human pancreatic islets. Endocrinology 2009; 150:5334-40. [PMID: 19819962 DOI: 10.1210/en.2009-0600] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The kinetics of insulin, glucagon and somatostatin release was studied in human pancreatic islets. Batches of 10-15 islets were perifused and the hormones measured with RIA in 30-sec fractions. Increase of glucose from 3 to 20 mm resulted in a brief pulse of glucagon coinciding with suppression of basal insulin and somatostatin release. There was a subsequent drop of glucagon release concomitant with the appearance of a pronounced pulse of insulin and a slightly delayed pulse of somatostatin. Continued exposure to 20 mm glucose generated pulsatile release of the three hormones with 7- to 8-min periods accounting for 60-70% of the secreted amounts. Glucose caused pronounced stimulation of average insulin and somatostatin release. However, the nadirs between the glucagon pulses were lower than the secretion at 3 mm glucose, resulting in 18% suppression of average release. The repetitive glucagon pulses were antisynchronous to coincident pulses of insulin and somatostatin. The resulting greater than 20-fold variations of the insulin to glucagon ratio might be essential for minute-to-minute regulation of the hepatic glucose production.
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Affiliation(s)
- Bo Hellman
- Department of Medical Cell Biology, University of Uppsala, Uppsala, Sweden.
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