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Leibold NS, Despa F. Neuroinflammation induced by amyloid-forming pancreatic amylin: Rationale for a mechanistic hypothesis. Biophys Chem 2024; 310:107252. [PMID: 38663120 PMCID: PMC11111340 DOI: 10.1016/j.bpc.2024.107252] [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: 11/15/2023] [Revised: 04/18/2024] [Accepted: 04/21/2024] [Indexed: 05/15/2024]
Abstract
Amylin is a systemic neuroendocrine hormone co-expressed and co-secreted with insulin by pancreatic β-cells. In persons with thype-2 diabetes, amylin forms pancreatic amyloid triggering inflammasome and interleukin-1β signaling and inducing β-cell apoptosis. Here, we summarize recent progress in understanding the potential link between amyloid-forming pancreatic amylin and Alzheimer's disease (AD). Clinical data describing amylin pathology in AD alongside mechanistic studies in animals are reviewed. Data from multiple research teams indicate higher amylin concentrations are associated with increased frequency of cognitive impairment and amylin co-aggregates with β-amyloid in AD-type dementia. Evidence from rodent models further suggests cerebrovascular amylin accumulation as a causative factor underlying neurological deficits. Analysis of relevant literature suggests that modulating the amylin-interleukin-1β pathway may provide an approach for counteracting neuroinflammation in AD.
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Affiliation(s)
- Noah S Leibold
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Florin Despa
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA.
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2
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Su Y, Ye L, Hu C, Zhang Y, Liu J, Shao L. Periodontitis as a promoting factor of T2D: current evidence and mechanisms. Int J Oral Sci 2023; 15:25. [PMID: 37321994 DOI: 10.1038/s41368-023-00227-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 04/12/2023] [Accepted: 04/26/2023] [Indexed: 06/17/2023] Open
Abstract
Periodontitis is an infectious disease caused by an imbalance between the local microbiota and host immune response. Epidemiologically, periodontitis is closely related to the occurrence, development, and poor prognosis of T2D and is recognized as a potential risk factor for T2D. In recent years, increasing attention has been given to the role of the virulence factors produced by disorders of the subgingival microbiota in the pathological mechanism of T2D, including islet β-cell dysfunction and insulin resistance (IR). However, the related mechanisms have not been well summarized. This review highlights periodontitis-derived virulence factors, reviews how these stimuli directly or indirectly regulate islet β-cell dysfunction. The mechanisms by which IR is induced in insulin-targeting tissues (the liver, visceral adipose tissue, and skeletal muscle) are explained, clarifying the influence of periodontitis on the occurrence and development of T2D. In addition, the positive effects of periodontal therapy on T2D are overviewed. Finally, the limitations and prospects of the current research are discussed. In summary, periodontitis is worthy of attention as a promoting factor of T2D. Understanding on the effect of disseminated periodontitis-derived virulence factors on the T2D-related tissues and cells may provide new treatment options for reducing the risk of T2D associated with periodontitis.
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Affiliation(s)
- Yuan Su
- Stomatology Center, Shunde Hospital, Southern Medical University (The First People's Hospital of Shunde), Foshan, China
- Stomatological Hospital, School of Stomatology, Southern Medical University, Guangzhou, China
| | - Leilei Ye
- Stomatological Hospital, School of Stomatology, Southern Medical University, Guangzhou, China
| | - Chen Hu
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yanli Zhang
- Stomatological Hospital, School of Stomatology, Southern Medical University, Guangzhou, China
| | - Jia Liu
- Stomatological Hospital, School of Stomatology, Southern Medical University, Guangzhou, China
| | - Longquan Shao
- Stomatological Hospital, School of Stomatology, Southern Medical University, Guangzhou, China.
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Serbis A, Giapros V, Tsamis K, Balomenou F, Galli-Tsinopoulou A, Siomou E. Beta Cell Dysfunction in Youth- and Adult-Onset Type 2 Diabetes: An Extensive Narrative Review with a Special Focus on the Role of Nutrients. Nutrients 2023; 15:2217. [PMID: 37432389 PMCID: PMC10180650 DOI: 10.3390/nu15092217] [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: 04/22/2023] [Revised: 05/04/2023] [Accepted: 05/06/2023] [Indexed: 07/12/2023] Open
Abstract
Traditionally a disease of adults, type 2 diabetes (T2D) has been increasingly diagnosed in youth, particularly among adolescents and young adults of minority ethnic groups. Especially, during the recent COVID-19 pandemic, obesity and prediabetes have surged not only in minority ethnic groups but also in the general population, further raising T2D risk. Regarding its pathogenesis, a gradually increasing insulin resistance due to central adiposity combined with a progressively defective β-cell function are the main culprits. Especially in youth-onset T2D, a rapid β-cell activity decline has been observed, leading to higher treatment failure rates, and early complications. In addition, it is well established that both the quantity and quality of food ingested by individuals play a key role in T2D pathogenesis. A chronic imbalance between caloric intake and expenditure together with impaired micronutrient intake can lead to obesity and insulin resistance on one hand, and β-cell failure and defective insulin production on the other. This review summarizes our evolving understanding of the pathophysiological mechanisms involved in defective insulin secretion by the pancreatic islets in youth- and adult-onset T2D and, further, of the role various micronutrients play in these pathomechanisms. This knowledge is essential if we are to curtail the serious long-term complications of T2D both in pediatric and adult populations.
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Affiliation(s)
- Anastasios Serbis
- Department of Pediatrics, School of Medicine, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece;
| | - Vasileios Giapros
- Neonatal Intensive Care Unit, School of Medicine, University of Ioannina, St. Νiarhcos Avenue, 45500 Ioannina, Greece (F.B.)
| | - Konstantinos Tsamis
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece
| | - Foteini Balomenou
- Neonatal Intensive Care Unit, School of Medicine, University of Ioannina, St. Νiarhcos Avenue, 45500 Ioannina, Greece (F.B.)
| | - Assimina Galli-Tsinopoulou
- Second Department of Pediatrics, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, AHEPA University Hospital, Stilponos Kyriakidi 1, 54636 Thessaloniki, Greece;
| | - Ekaterini Siomou
- Department of Pediatrics, School of Medicine, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece;
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Mazzoli A, Sardi C, Breasson L, Theilig F, Becattini B, Solinas G. JNK1 ablation improves pancreatic β-cell mass and function in db/db diabetic mice without affecting insulin sensitivity and adipose tissue inflammation. FASEB Bioadv 2021; 3:94-107. [PMID: 33615154 PMCID: PMC7876705 DOI: 10.1096/fba.2020-00081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/12/2020] [Accepted: 12/16/2020] [Indexed: 12/15/2022] Open
Abstract
The cJun N‐terminal Kinases (JNK) emerged as a major link between obesity and insulin resistance, but their role in the loss of pancreatic β‐cell mass and function driving the progression from insulin resistance to type‐2 diabetes and in the complications of diabetes was not investigated to the same extent. Furthermore, it was shown that pan‐JNK inhibition exacerbates kidney damage in the db/db model of obesity‐driven diabetes. Here we investigate the role of JNK1 in the db/db model of obesity‐driven type‐2 diabetes. Mice with systemic ablation of JNK1 (JNK1−/−) were backcrossed for more than 10 generations in db/+ C57BL/KS mice to generate db/db‐JNK1−/− mice and db/db control mice. To define the role of JNK1 in the loss of β‐cell mass and function occurring during obesity‐driven diabetes we performed comprehensive metabolic phenotyping, evaluated steatosis and metabolic inflammation, performed morphometric and cellular composition analysis of pancreatic islets, and evaluated kidney function in db/db‐JNK1−/− mice and db/db controls. db/db‐JNK1−/− mice and db/db control mice developed insulin resistance, fatty liver, and metabolic inflammation to a similar extent. However, db/db‐JNK1−/− mice displayed better glucose tolerance and improved insulin levels during glucose tolerance test, higher pancreatic insulin content, and larger pancreatic islets with more β‐cells than db/db mice. Finally, albuminuria, kidney histopathology, kidney inflammation and oxidative stress in db/db‐JNK1−/− mice and in db/db mice were similar. Our data indicate that selective JNK1 ablation improves glucose tolerance in db/db mice by reducing the loss of functional β‐cells occurring in the db/db mouse model of obesity‐driven diabetes, without significantly affecting metabolic inflammation, steatosis, and insulin sensitivity. Furthermore, we have found that, differently from what previously reported for pan‐JNK inhibitors, selective JNK1 ablation does not exacerbate kidney dysfunction in db/db mice. We conclude that selective JNK1 inactivation may have a superior therapeutic index than pan‐JNK inhibition in obesity‐driven diabetes.
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Affiliation(s)
- Arianna Mazzoli
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research Department of Molecular and Clinical Medicine Institute of Medicine University of Gothenburg Gothenburg Sweden
| | - Claudia Sardi
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research Department of Molecular and Clinical Medicine Institute of Medicine University of Gothenburg Gothenburg Sweden
| | - Ludovic Breasson
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research Department of Molecular and Clinical Medicine Institute of Medicine University of Gothenburg Gothenburg Sweden
| | - Franziska Theilig
- Institute of Anatomy Christian Albrechts-University Kiel Kiel Germany
| | - Barbara Becattini
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research Department of Molecular and Clinical Medicine Institute of Medicine University of Gothenburg Gothenburg Sweden
| | - Giovanni Solinas
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research Department of Molecular and Clinical Medicine Institute of Medicine University of Gothenburg Gothenburg Sweden
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Templin AT, Mellati M, Meier DT, Esser N, Hogan MF, Castillo JJ, Akter R, Raleigh DP, Zraika S, Hull RL, Kahn SE. Low concentration IL-1β promotes islet amyloid formation by increasing hIAPP release from humanised mouse islets in vitro. Diabetologia 2020; 63:2385-2395. [PMID: 32728889 PMCID: PMC7529980 DOI: 10.1007/s00125-020-05232-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/05/2020] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS Aggregation of the beta cell secretory product human islet amyloid polypeptide (hIAPP) results in islet amyloid deposition, a pathological feature of type 2 diabetes. Amyloid formation is associated with increased levels of islet IL-1β as well as beta cell dysfunction and death, but the mechanisms that promote amyloid deposition in situ remain unclear. We hypothesised that physiologically relevant concentrations of IL-1β stimulate beta cell islet amyloid polypeptide (IAPP) release and promote amyloid formation. METHODS We used a humanised mouse model of endogenous beta cell hIAPP expression to examine whether low (pg/ml) concentrations of IL-1β promote islet amyloid formation in vitro. Amyloid-forming islets were cultured for 48 h in the presence or absence of IL-1β with or without an IL-1β neutralising antibody. Islet morphology was assessed by immunohistochemistry and islet mRNA expression, hormone content and release were also quantified. Cell-free thioflavin T assays were used to monitor hIAPP aggregation kinetics in the presence and absence of IL-1β. RESULTS Treatment with a low concentration of IL-1β (4 pg/ml) for 48 h increased islet amyloid prevalence (93.52 ± 3.89% vs 43.83 ± 9.67% amyloid-containing islets) and amyloid severity (4.45 ± 0.82% vs 2.16 ± 0.50% amyloid area/islet area) in hIAPP-expressing mouse islets in vitro. This effect of IL-1β was reduced when hIAPP-expressing islets were co-treated with an IL-1β neutralising antibody. Cell-free hIAPP aggregation assays showed no effect of IL-1β on hIAPP aggregation in vitro. Low concentration IL-1β did not increase markers of the unfolded protein response (Atf4, Ddit3) or alter proIAPP processing enzyme gene expression (Pcsk1, Pcsk2, Cpe) in hIAPP-expressing islets. However, release of IAPP and insulin were increased over 48 h in IL-1β-treated vs control islets (IAPP 0.409 ± 0.082 vs 0.165 ± 0.051 pmol/5 islets; insulin 87.5 ± 8.81 vs 48.3 ± 17.3 pmol/5 islets), and this effect was blocked by co-treatment with IL-1β neutralising antibody. CONCLUSIONS/INTERPRETATION Under amyloidogenic conditions, physiologically relevant levels of IL-1β promote islet amyloid formation by increasing beta cell release of IAPP. Neutralisation of this effect of IL-1β may decrease the deleterious effects of islet amyloid formation on beta cell function and survival.
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Affiliation(s)
- Andrew T Templin
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Mahnaz Mellati
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Daniel T Meier
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Nathalie Esser
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Meghan F Hogan
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Joseph J Castillo
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Rehana Akter
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA
| | - Daniel P Raleigh
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA
| | - Sakeneh Zraika
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Rebecca L Hull
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA
| | - Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, Veteran Affairs Puget Sound Health Care System (151) and University of Washington, 1660 S. Columbian Way, Seattle, WA, 98108, USA.
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Marchetti P, Suleiman M, De Luca C, Baronti W, Bosi E, Tesi M, Marselli L. A direct look at the dysfunction and pathology of the β cells in human type 2 diabetes. Semin Cell Dev Biol 2020; 103:83-93. [PMID: 32417220 DOI: 10.1016/j.semcdb.2020.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/27/2020] [Accepted: 04/09/2020] [Indexed: 12/25/2022]
Abstract
β cells uniquely produce and secrete insulin under the control of several, integrated signals, to maintain blood glucose concentrations within a narrow physiological interval. β cell failure is key to the onset and progression of type 2 diabetes, due to impaired function and reduced mass. In this review we focus on several features of human β cell dysfunction and pathology in type 2 diabetes, as revealed by direct assessment of isolated islet traits and examination of pancreatic tissue from organ donors, surgical samples or autoptic specimens. Insulin secretion defects and pathology findings are discussed in relation to some of the major underlying mechanisms, to also provide clues for conceiving better prevention and treatment of type 2 diabetes by targeting the pancreatic β cells.
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Affiliation(s)
- Piero Marchetti
- Department of Clinical and Experimental Medicine - University of Pisa, Via Savi 10, Pisa, Italy.
| | - Mara Suleiman
- Department of Clinical and Experimental Medicine - University of Pisa, Via Savi 10, Pisa, Italy
| | - Carmela De Luca
- Department of Clinical and Experimental Medicine - University of Pisa, Via Savi 10, Pisa, Italy
| | - Walter Baronti
- Department of Clinical and Experimental Medicine - University of Pisa, Via Savi 10, Pisa, Italy
| | - Emanuele Bosi
- Department of Clinical and Experimental Medicine - University of Pisa, Via Savi 10, Pisa, Italy
| | - Marta Tesi
- Department of Clinical and Experimental Medicine - University of Pisa, Via Savi 10, Pisa, Italy
| | - Lorella Marselli
- Department of Clinical and Experimental Medicine - University of Pisa, Via Savi 10, Pisa, Italy
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7
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Ibrahim M, MacFarlane EM, Matteo G, Hoyeck MP, Rick KRC, Farokhi S, Copley CM, O'Dwyer S, Bruin JE. Functional cytochrome P450 1A enzymes are induced in mouse and human islets following pollutant exposure. Diabetologia 2020; 63:162-178. [PMID: 31776611 PMCID: PMC6890627 DOI: 10.1007/s00125-019-05035-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 08/30/2019] [Indexed: 02/08/2023]
Abstract
AIMS/HYPOTHESIS Exposure to environmental pollution has been consistently linked to diabetes incidence in humans, but the potential causative mechanisms remain unclear. Given the critical role of regulated insulin secretion in maintaining glucose homeostasis, environmental chemicals that reach the endocrine pancreas and cause beta cell injury are of particular concern. We propose that cytochrome P450 (CYP) enzymes, which are involved in metabolising xenobiotics, could serve as a useful biomarker for direct exposure of islets to pollutants. Moreover, functional CYP enzymes in islets could also impact beta cell physiology. The aim of this study was to determine whether CYP1A enzymes are activated in islets following direct or systemic exposure to environmental pollutants. METHODS Immortalised liver (HepG2) and rodent pancreatic endocrine cell lines (MIN6, βTC-6, INS1, α-TC1, α-TC3), as well as human islets, were treated in vitro with known CYP1A inducers 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 3-methylcholanthrene (3-MC). In addition, mice were injected with either a single high dose of TCDD or multiple low doses of TCDD in vivo, and islets were isolated 1, 7 or 14 days later. RESULTS CYP1A enzymes were not activated in any of the immortalised beta or alpha cell lines tested. However, both 3-MC and TCDD potently induced CYP1A1 gene expression and modestly increased CYP1A1 enzyme activity in human islets after 48 h. The induction of CYP1A1 in human islets by TCDD was prevented by cotreatment with a cytokine mixture. After a systemic single high-dose TCDD injection, CYP1A1 enzyme activity was induced in mouse islets ~2-fold, ~40-fold and ~80-fold compared with controls after 1, 7 and 14 days, respectively, in vivo. Multiple low-dose TCDD exposure in vivo also caused significant upregulation of Cyp1a1 in mouse islets. Direct TCDD exposure to human and mouse islets in vitro resulted in suppressed glucose-induced insulin secretion. A single high-dose TCDD injection resulted in lower plasma insulin levels, as well as a pronounced increase in beta cell death. CONCLUSIONS/INTERPRETATION Transient exposure to TCDD results in long-term upregulation of CYP1A1 enzyme activity in islets. This provides evidence for direct exposure of islets to lipophilic pollutants in vivo and may have implications for islet physiology.
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Affiliation(s)
- Muna Ibrahim
- Laboratory of Molecular and Cellular Medicine, Department of Cellular & Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Erin M MacFarlane
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Geronimo Matteo
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Myriam P Hoyeck
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Kayleigh R C Rick
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Salar Farokhi
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Catherine M Copley
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Shannon O'Dwyer
- Laboratory of Molecular and Cellular Medicine, Department of Cellular & Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Jennifer E Bruin
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada.
- Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada.
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Gerst F, Wagner R, Oquendo MB, Siegel-Axel D, Fritsche A, Heni M, Staiger H, Häring HU, Ullrich S. What role do fat cells play in pancreatic tissue? Mol Metab 2019; 25:1-10. [PMID: 31113756 PMCID: PMC6600604 DOI: 10.1016/j.molmet.2019.05.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 04/10/2019] [Accepted: 05/01/2019] [Indexed: 02/07/2023] Open
Abstract
Background It is now generally accepted that obesity is a major risk factor for type 2 diabetes mellitus (T2DM). Hepatic steatosis in particular, as well as visceral and ectopic fat accumulation within tissues, is associated with the development of the disease. We recently presented the first study on isolated human pancreatic adipocytes and their interaction with islets [Gerst, F., Wagner, R., Kaiser, G., Panse, M., Heni, M., Machann, J., et al., 2017. Metabolic crosstalk between fatty pancreas and fatty liver: effects on local inflammation and insulin secretion. Diabetologia 60(11):2240–2251.]. The results indicate that the function of adipocytes depends on the overall metabolic status in humans which, in turn, differentially affects islet hormone release. Scope of Review This review summarizes former and recent studies on factors derived from adipocytes and their effects on insulin-secreting β-cells, with particular emphasis on the human pancreas. The adipocyte secretome is discussed with a special focus on its influence on insulin secretion, β-cell survival and apoptotic β-cell death. Major Conclusions Human pancreatic adipocytes store lipids and release adipokines, metabolites, and pro-inflammatory molecules in response to the overall metabolic, humoral, and neuronal status. The differentially regulated adipocyte secretome impacts on endocrine function, i.e., insulin secretion, β-cell survival and death which interferes with glycemic control. This review attempts to explain why the extent of pancreatic steatosis is associated with reduced insulin secretion in some studies but not in others.
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Affiliation(s)
- Felicia Gerst
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Robert Wagner
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Morgana Barroso Oquendo
- German Center for Diabetes Research (DZD), Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Dorothea Siegel-Axel
- German Center for Diabetes Research (DZD), Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Andreas Fritsche
- German Center for Diabetes Research (DZD), Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Martin Heni
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Harald Staiger
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Institute of Pharmaceutical Sciences, Department of Pharmacy and Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Hans-Ulrich Häring
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Susanne Ullrich
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany.
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9
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Yan C, Deng C, Liu X, Chen Y, Ye J, Cai R, Shen Y, Tang H. TNF-α induction of IL-6 in alveolar type II epithelial cells: Contributions of JNK/c-Jun/AP-1 element, C/EBPδ/C/EBP binding site and IKK/NF-κB p65/κB site. Mol Immunol 2018; 101:585-596. [PMID: 29887504 DOI: 10.1016/j.molimm.2018.05.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/26/2018] [Accepted: 05/07/2018] [Indexed: 10/14/2022]
Abstract
Although participation of IL-6 in lung inflammation has been widely elucidated, the transcriptional regulation of its generation in alveolar type II cells stimulated by TNF-α remain unclear. Here, we find that TNF-α significantly induces IL-6 production, and TNF-α induction of IL-6 is mainly regulated at transcriptional level. Upon stimulated by TNF-α, Activator Protein-1 (AP-1)-mediated transcriptional activity is apparently increased in alveolar type II epithelial cells, which might be derived from elevated phosphorylation of JNK and subsequent activation of c-Jun. Either down-regulation of c-Jun or the AP-1 site mutation leads to significant reduction of IL-6 expression. In contrast, ectopic expression of c-Jun notably increases IL-6 generation. So, c-Jun, one of the AP-1 family members, plays a pivotal role in TNF-α-induced IL-6 generation. CCAAT/enhancer binding protein δ (C/EBPδ) expression is significantly amplified by TNF-α, which may contribute to the rise of C/EBP activity in alveolar type II cells. C/EBPδ shRNA treatment results in attenuation of IL-6 expression in the cells, which is consistent with data by introduction of mutations into the C/EBP site in the promoter. However, overexpression of C/EBPδ greatly increases the IL-6 promoter activity. In addition, data regarding another transactivator in the family-C/EBPβ show that it does not affect IL-6 production. We also find that the IKK/NF-κB p65 pathway is activated in TNF-α-treated alveolar type II epithelial cells, and plays an essential role in positive regulation of IL-6 expression in TNF-α-treated alveolar type II epithelial cells via knockdown or forced expression of NF-κB p65, or elimination of κB sites in the IL-6 promoter. Notably, IL-6 promoter-driven luciferase production in primary alveolar type II epithelial cells can also be increased by the ectopic expression of c-Jun, C/EBPδ, and NF-κB p65, respectively. Collectively, our data provide insights into molecular mechanism involved in IL-6 expression in alveolar type II epithelial cells on TNF-α treatment, which provides a theoretical basis for specific inhibition of IL-6 production at the transcriptional level.
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Affiliation(s)
- Chunguang Yan
- Department of Pathogenic Biology and Immunology, Medical School of Southeast University, Nanjing, 210009, China.
| | - Chunmin Deng
- Department of Pathogenic Biology and Immunology, Medical School of Southeast University, Nanjing, 210009, China.
| | - Xiufang Liu
- Department of Pathogenic Biology and Immunology, Medical School of Southeast University, Nanjing, 210009, China
| | - Yutong Chen
- Department of Pathogenic Biology and Immunology, Medical School of Southeast University, Nanjing, 210009, China
| | - Jiawei Ye
- Department of Pathogenic Biology and Immunology, Medical School of Southeast University, Nanjing, 210009, China
| | - Rentian Cai
- Department of Infectious Diseases, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, China
| | - Yanfei Shen
- Department of Bioengineering, Medical School of Southeast University, Nanjing, 210009, China
| | - Huifang Tang
- Zhejiang Respiratory Drugs Research Laboratory of the State Food and Drug Administration of China, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China.
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10
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Reddy S, Krogvold L, Martin C, Holland R, Choi J, Woo H, Wu F, Dahl-Jørgensen K. Distribution of IL-1β immunoreactive cells in pancreatic biopsies from living volunteers with new-onset type 1 diabetes: comparison with donors without diabetes and with longer duration of disease. Diabetologia 2018; 61:1362-1373. [PMID: 29589071 DOI: 10.1007/s00125-018-4600-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 02/14/2018] [Indexed: 10/17/2022]
Abstract
AIMS/HYPOTHESIS Although IL-1β is considered a key mediator of beta cell destruction, its cellular expression in islets during early type 1 diabetes remains unclear. We compared its expression in rare pancreatic biopsies from new-onset living volunteers with its expression in cadaveric pancreas sections from non-diabetic autoantibody-positive and -negative individuals and those with long-standing disease. METHODS Pancreatic biopsy sections from six new-onset living volunteers (group 1) and cadaveric sections from 13 non-diabetic autoantibody-negative donors (group 2), four non-diabetic autoantibody-positive donors (group 3) and nine donors with diabetes of longer duration (0.25-12 years of disease; group 4) were triple-immunostained for IL-1β, insulin and glucagon. Intra- and peri-islet IL-1β-positive cells in insulin-positive and -negative islets and in random exocrine fields were enumerated. RESULTS The mean number of IL-1β-positive cells per islet from each donor in peri- and intra-islet regions was <1.25 and <0.5, respectively. In all study groups, the percentage of islets with IL-1β cells in peri- and/or intra-islet regions was highly variable and ranged from 4.48% to 17.59% in group 1, 1.42% to 44.26% in group 2, 7.93% to 17.53% in group 3 and 3.85% to 42.86% in group 4, except in a single case where the value was 75%. In 25/32 donors, a higher percentage of islets showed IL-1β-positive cells in peri-islet than in intra-islet regions. In sections from diabetic donors (groups 1 and 4), a higher mean number of IL-1β-positive cells occurred in insulin-positive islets than in insulin-negative islets. In group 2, 70-90% of islets in 3/13 sections had weak-to-moderate IL-1β staining in alpha cells but staining was virtually absent or substantially reduced in the remaining groups. The mean number of exocrine IL-1β-positive cells in group 1 was lower than in the other groups. CONCLUSIONS/INTERPRETATION At onset of type 1 diabetes, the low number of islet-associated IL-1β-positive cells may be insufficient to elicit beta cell destruction. The variable expression in alpha cells in groups 2-4 suggests their cellular heterogeneity and probable physiological role. The significance of a higher but variable number of exocrine IL-1β-positive cells seen in non-diabetic individuals and those with long-term type 1 diabetes remains unclear.
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Affiliation(s)
- Shiva Reddy
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
| | - Lars Krogvold
- Division of Paediatric and Adolescent Medicine, Oslo University Hospital, Oslo, Norway
- Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Charlton Martin
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Rebecca Holland
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Jaimin Choi
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Hannah Woo
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Fiona Wu
- Diabetes Unit, Auckland District Health Board, Auckland, New Zealand
| | - Knut Dahl-Jørgensen
- Division of Paediatric and Adolescent Medicine, Oslo University Hospital, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
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11
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Llacua LA, Faas MM, de Vos P. Extracellular matrix molecules and their potential contribution to the function of transplanted pancreatic islets. Diabetologia 2018; 61:1261-1272. [PMID: 29306997 PMCID: PMC6449002 DOI: 10.1007/s00125-017-4524-8] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 10/18/2017] [Indexed: 12/18/2022]
Abstract
Extracellular matrix (ECM) molecules are responsible for structural and biochemical support, as well as for regulation of molecular signalling and tissue repair in many organ structures, including the pancreas. In pancreatic islets, collagen type IV and VI, and laminins are the most abundant molecules, but other ECM molecules are also present. The ECM interacts with specific combinations of integrin α/β heterodimers on islet cells and guides many cellular processes. More specifically, some ECM molecules are involved in beta cell survival, function and insulin production, while others can fine tune the susceptibility of islet cells to cytokines. Further, some ECM induce release of growth factors to facilitate tissue repair. During enzymatic isolation of islets for transplantation, the ECM is damaged, impacting islet function. However, restoration of the ECM in human islets (for example by adding ECM to the interior of immunoprotective capsules) has been shown to enhance islet function. Here, we provide current insight into the role of ECM molecules in islet function and discuss the clinical potential of ECM manipulation to enhance pancreatic islet function and survival.
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Affiliation(s)
- L Alberto Llacua
- Section of Immunoendocrinology, Department of Pathology and Medical Biology, University of Groningen, Hanzeplein 1 EA11, 9700 RB, Groningen, the Netherlands.
- University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
| | - Marijke M Faas
- Section of Immunoendocrinology, Department of Pathology and Medical Biology, University of Groningen, Hanzeplein 1 EA11, 9700 RB, Groningen, the Netherlands
- University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Paul de Vos
- Section of Immunoendocrinology, Department of Pathology and Medical Biology, University of Groningen, Hanzeplein 1 EA11, 9700 RB, Groningen, the Netherlands
- University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
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12
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Kycia I, Wolford BN, Huyghe JR, Fuchsberger C, Vadlamudi S, Kursawe R, Welch RP, Albanus RD, Uyar A, Khetan S, Lawlor N, Bolisetty M, Mathur A, Kuusisto J, Laakso M, Ucar D, Mohlke KL, Boehnke M, Collins FS, Parker SCJ, Stitzel ML. A Common Type 2 Diabetes Risk Variant Potentiates Activity of an Evolutionarily Conserved Islet Stretch Enhancer and Increases C2CD4A and C2CD4B Expression. Am J Hum Genet 2018; 102:620-635. [PMID: 29625024 DOI: 10.1016/j.ajhg.2018.02.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 02/22/2018] [Indexed: 01/17/2023] Open
Abstract
Genome-wide association studies (GWASs) and functional genomics approaches implicate enhancer disruption in islet dysfunction and type 2 diabetes (T2D) risk. We applied genetic fine-mapping and functional (epi)genomic approaches to a T2D- and proinsulin-associated 15q22.2 locus to identify a most likely causal variant, determine its direction of effect, and elucidate plausible target genes. Fine-mapping and conditional analyses of proinsulin levels of 8,635 non-diabetic individuals from the METSIM study support a single association signal represented by a cluster of 16 strongly associated (p < 10-17) variants in high linkage disequilibrium (r2 > 0.8) with the GWAS index SNP rs7172432. These variants reside in an evolutionarily and functionally conserved islet and β cell stretch or super enhancer; the most strongly associated variant (rs7163757, p = 3 × 10-19) overlaps a conserved islet open chromatin site. DNA sequence containing the rs7163757 risk allele displayed 2-fold higher enhancer activity than the non-risk allele in reporter assays (p < 0.01) and was differentially bound by β cell nuclear extract proteins. Transcription factor NFAT specifically potentiated risk-allele enhancer activity and altered patterns of nuclear protein binding to the risk allele in vitro, suggesting that it could be a factor mediating risk-allele effects. Finally, the rs7163757 proinsulin-raising and T2D risk allele (C) was associated with increased expression of C2CD4B, and possibly C2CD4A, both of which were induced by inflammatory cytokines, in human islets. Together, these data suggest that rs7163757 contributes to genetic risk of islet dysfunction and T2D by increasing NFAT-mediated islet enhancer activity and modulating C2CD4B, and possibly C2CD4A, expression in (patho)physiologic states.
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Affiliation(s)
- Ina Kycia
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Brooke N Wolford
- National Human Genome Research Institute, NIH, Bethesda, MD 20892, USA
| | - Jeroen R Huyghe
- Department of Biostatistics and Center for Statistical Genetics, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA
| | - Christian Fuchsberger
- Department of Biostatistics and Center for Statistical Genetics, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Romy Kursawe
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Ryan P Welch
- Department of Biostatistics and Center for Statistical Genetics, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ricardo d'Oliveira Albanus
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Asli Uyar
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Shubham Khetan
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Nathan Lawlor
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Mohan Bolisetty
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Anubhuti Mathur
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Johanna Kuusisto
- Department of Medicine, University of Eastern Finland and Kuopio University Hospital, 70210 Kuopio, Finland
| | - Markku Laakso
- Department of Medicine, University of Eastern Finland and Kuopio University Hospital, 70210 Kuopio, Finland
| | - Duygu Ucar
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA; Institute of Systems Genomics, University of Connecticut Health Center, Farmington, CT 06032, USA
| | - Karen L Mohlke
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Michael Boehnke
- Department of Biostatistics and Center for Statistical Genetics, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA
| | - Francis S Collins
- National Human Genome Research Institute, NIH, Bethesda, MD 20892, USA
| | - Stephen C J Parker
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA; Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael L Stitzel
- Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA; Institute of Systems Genomics, University of Connecticut Health Center, Farmington, CT 06032, USA.
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13
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Kaminitz A, Ash S, Askenasy N. Neutralization Versus Reinforcement of Proinflammatory Cytokines to Arrest Autoimmunity in Type 1 Diabetes. Clin Rev Allergy Immunol 2018; 52:460-472. [PMID: 27677500 DOI: 10.1007/s12016-016-8587-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
As physiological pathways of intercellular communication produced by all cells, cytokines are involved in the pathogenesis of inflammatory insulitis as well as pivotal mediators of immune homeostasis. Proinflammatory cytokines including interleukins, interferons, transforming growth factor-β, tumor necrosis factor-α, and nitric oxide promote destructive insulitis in type 1 diabetes through amplification of the autoimmune reaction, direct toxicity to β-cells, and sensitization of islets to apoptosis. The concept that neutralization of cytokines may be of therapeutic benefit has been tested in few clinical studies, which fell short of inducing sustained remission or achieving disease arrest. Therapeutic failure is explained by the redundant activities of individual cytokines and their combinations, which are rather dispensable in the process of destructive insulitis because other cytolytic pathways efficiently compensate their deficiency. Proinflammatory cytokines are less redundant in regulation of the inflammatory reaction, displaying protective effects through restriction of effector cell activity, reinforcement of suppressor cell function, and participation in islet recovery from injury. Our analysis suggests that the role of cytokines in immune homeostasis overrides their contribution to β-cell death and may be used as potent immunomodulatory agents for therapeutic purposes rather than neutralized.
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Affiliation(s)
- Ayelet Kaminitz
- The Leah and Edward M. Frankel Laboratory of Experimental Bone Marrow Transplantation, 14 Kaplan Street, Petach Tikva, Israel, 49202
| | - Shifra Ash
- The Leah and Edward M. Frankel Laboratory of Experimental Bone Marrow Transplantation, 14 Kaplan Street, Petach Tikva, Israel, 49202
| | - Nadir Askenasy
- The Leah and Edward M. Frankel Laboratory of Experimental Bone Marrow Transplantation, 14 Kaplan Street, Petach Tikva, Israel, 49202.
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14
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Kosobrodova E, Gan WJ, Kondyurin A, Thorn P, Bilek MMM. Improved Multiprotein Microcontact Printing on Plasma Immersion Ion Implanted Polystyrene. ACS APPLIED MATERIALS & INTERFACES 2018; 10:227-237. [PMID: 29211435 DOI: 10.1021/acsami.7b15545] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Multiprotein micropatterning allows the creation of complex, controlled microenvironments for single cells that can be used for the study of the localized effects of various proteins and signals on cell survival, development, and functions. To enable analysis of cell interactions with microprinted proteins, the multiprotein micropattern must have low cross-contamination and high long-term stability in a cell culture medium. To achieve this, we employed an optimized plasma ion immersion implantation (PIII) treatment to provide polystyrene (PS) with the ability to covalently immobilize proteins on contact while retaining sufficient transparency and suitable surface properties for contact printing and retention of protein activity. The quality and long-term stability of the micropatterns on untreated and PIII treated PS were compared with those on glass using confocal microscopy. The protein micropattern on the PIII treated PS was more uniform and had a significantly higher contrast that was not affected by long-term incubation in cell culture media because the proteins were covalently bonded to PIII treated PS. The immunostaining of mouse pancreatic β cells interacting with E-cadherin and fibronectin striped surfaces showed phosphorylated paxillin concentrated on cell edges over the fibronectin stripes. This indicates that multiprotein micropatterns printed on PIII treated PS can be used for high-resolution studies of local influence on cell morphology and protein production.
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Affiliation(s)
- E Kosobrodova
- The School of Physics, University of Sydney , Sydney, New South Wales 2006, Australia
| | - W J Gan
- Department of Physiology, Sydney Medical School, Charles Perkins Centre, University of Sydney , Sydney, New South Wales 2006, Australia
| | - A Kondyurin
- The School of Physics, University of Sydney , Sydney, New South Wales 2006, Australia
| | - P Thorn
- Department of Physiology, Sydney Medical School, Charles Perkins Centre, University of Sydney , Sydney, New South Wales 2006, Australia
| | - M M M Bilek
- The School of Physics, University of Sydney , Sydney, New South Wales 2006, Australia
- Department of Physiology, Sydney Medical School, Charles Perkins Centre, University of Sydney , Sydney, New South Wales 2006, Australia
- The School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney , Sydney, New South Wales 2006, Australia
- The Australian Institute of Nanoscale Science and Technology, University of Sydney , Sydney, New South Wales 2006, Australia
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15
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Garcia-Contreras M, Tamayo-Garcia A, Pappan KL, Michelotti GA, Stabler CL, Ricordi C, Buchwald P. Metabolomics Study of the Effects of Inflammation, Hypoxia, and High Glucose on Isolated Human Pancreatic Islets. J Proteome Res 2017; 16:2294-2306. [PMID: 28452488 PMCID: PMC5557342 DOI: 10.1021/acs.jproteome.7b00160] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The transplantation of human pancreatic islets is a therapeutic possibility for a subset of type 1 diabetic patients who experience severe hypoglycemia. Pre- and post-transplantation loss in islet viability and function, however, is a major efficacy-limiting impediment. To investigate the effects of inflammation and hypoxia, the main obstacles hampering the survival and function of isolated, cultured, and transplanted islets, we conducted a comprehensive metabolomics evaluation of human islets in parallel with dynamic glucose-stimulated insulin release (GSIR) perifusion studies for functional evaluation. Metabolomics profiling of media and cell samples identified a total of 241 and 361 biochemicals, respectively. Metabolites that were altered in highly significant manner in both included, for example, kynurenine, kynurenate, citrulline, and mannitol/sorbitol under inflammation (all elevated) plus lactate (elevated) and N-formylmethionine (depressed) for hypoxia. Dynamic GSIR experiments, which capture both first- and second-phase insulin release, found severely depressed insulin-secretion under hypoxia, whereas elevated baseline and stimulated insulin-secretion was measured for islet exposed to the inflammatory cytokine cocktail (IL-1β, IFN-γ, and TNF-α). Because of the uniquely large changes observed in kynurenine and kynurenate, they might serve as potential biomarkers of islet inflammation, and indoleamine-2,3-dioxygenase on the corresponding pathway could be a worthwhile therapeutic target to dampen inflammatory effects.
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Affiliation(s)
- Marta Garcia-Contreras
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, FL, USA
- Ri.Med, Palermo, Italy
- Catholyc University of Valencia, Valencia, Spain
| | | | | | | | - Cherie L. Stabler
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Camillo Ricordi
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, FL, USA
- Ri.Med, Palermo, Italy
| | - Peter Buchwald
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, FL, USA
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16
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Arous C, Wehrle-Haller B. Role and impact of the extracellular matrix on integrin-mediated pancreatic β-cell functions. Biol Cell 2017; 109:223-237. [PMID: 28266044 DOI: 10.1111/boc.201600076] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/01/2017] [Accepted: 03/02/2017] [Indexed: 12/17/2022]
Abstract
Understanding the organisation and role of the extracellular matrix (ECM) in islets of Langerhans is critical for maintaining pancreatic β-cells, and to recognise and revert the physiopathology of diabetes. Indeed, integrin-mediated adhesion signalling in response to the pancreatic ECM plays crucial roles in β-cell survival and insulin secretion, two major functions, which are affected in diabetes. Here, we would like to present an update on the major components of the pancreatic ECM, their role during integrin-mediated cell-matrix adhesions and how they are affected during diabetes. To treat diabetes, a promising approach consists in replacing β-cells by transplantation. However, efficiency is low, because β-cells suffer of anoikis, due to enzymatic digestion of the pancreatic ECM, which affects the survival of insulin-secreting β-cells. The strategy of adding ECM components during transplantation, to reproduce the pancreatic microenvironment, is a challenging task, as many of the regulatory mechanisms that control ECM deposition and turnover are not sufficiently understood. A better comprehension of the impact of the ECM on the adhesion and integrin-dependent signalling in β-cells is primordial to improve the healthy state of islets to prevent the onset of diabetes as well as for enhancing the efficiency of the islet transplantation therapy.
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Affiliation(s)
- Caroline Arous
- Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Geneva, Switzerland
| | - Bernhard Wehrle-Haller
- Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Geneva, Switzerland
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17
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Solinas G, Becattini B. JNK at the crossroad of obesity, insulin resistance, and cell stress response. Mol Metab 2016; 6:174-184. [PMID: 28180059 PMCID: PMC5279903 DOI: 10.1016/j.molmet.2016.12.001] [Citation(s) in RCA: 265] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 11/28/2016] [Accepted: 12/02/2016] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The cJun-N-terminal-kinase (JNK) plays a central role in the cell stress response, with outcomes ranging from cell death to cell proliferation and survival, depending on the specific context. JNK is also one of the most investigated signal transducers in obesity and insulin resistance, and studies have identified new molecular mechanisms linking obesity and insulin resistance. Emerging evidence indicates that whereas JNK1 and JNK2 isoforms promote the development of obesity and insulin resistance, JNK3 activity protects from excessive adiposity. Furthermore, current evidence indicates that JNK activity within specific cell types may, in specific stages of disease progression, promote cell tolerance to the stress associated with obesity and type-2 diabetes. SCOPE OF REVIEW This review provides an overview of the current literature on the role of JNK in the progression from obesity to insulin resistance, NAFLD, type-2 diabetes, and diabetes complications. MAJOR CONCLUSION Whereas current evidence indicates that JNK1/2 inhibition may improve insulin sensitivity in obesity, the role of JNK in the progression from insulin resistance to diabetes, and its complications is largely unresolved. A better understanding of the role of JNK in the stress response to obesity and type-2 diabetes, and the development of isoform-specific inhibitors with specific tissue distribution will be necessary to exploit JNK as possible drug target for the treatment of type-2 diabetes.
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Affiliation(s)
- Giovanni Solinas
- The Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, 41345 Gothenburg, Sweden.
| | - Barbara Becattini
- The Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, 41345 Gothenburg, Sweden
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18
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Li Y, Zhang T, Huang Q, Sun Y, Chang X, Zhang H, Zhu Y, Han X. Inhibition of tumor suppressor p53 preserves glycation-serum induced pancreatic beta-cell demise. Endocrine 2016; 54:383-395. [PMID: 27160820 DOI: 10.1007/s12020-016-0979-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 04/30/2016] [Indexed: 12/15/2022]
Abstract
Tumor suppressor p53 is a transcriptional factor that determines cell fate in response to multiple stressors, such as oxidative stress and endoplasmic reticulum stress, in the majority of cells. However, its role in pancreatic beta cells is not well documented. Our previous research has revealed that glycation-serum (GS) induced pancreatic beta-cell demise through the AGEs-RAGE pathway. In the present study, we investigated the role of p53 in GS-related beta-cell demise. Using pancreatic islets beta-cell line INS-1 cells, we found that with GS treatment, the transcriptional activity of p53 was significantly evoked due to the increased amount of nuclear p53 protein. Resveratrol (RSV) was capable of further enhancing this transcriptional ability and consequently increased the population of dead beta cells under GS exposure. In contrast, inhibiting this transcriptional activity via p53 interference greatly protected beta cells from the damage provoked by GS, as well as damage strengthened by RSV. However, the pharmacological activation of PPARγ with troglitazone (TRO) only suppressed GS-induced, not RSV-induced, p53 activity. Moreover, the activation of PPARγ greatly preserved beta cells from GS-induced death. This protective effect recurred due to improved mitochondrial function with Bcl2 overexpression. Further, p53 activation could induce cellular apoptosis in primary rat islets. Our findings explore the broader role of p53 in regulating pancreatic beta-cell demise in the presence of GS and may provide a therapeutic target for the treatment and prevention of diabetes.
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Affiliation(s)
- Y Li
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - T Zhang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Q Huang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Y Sun
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - X Chang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - H Zhang
- Department of Obstetrics and Gynecology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Y Zhu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, 210029, Jiangsu, China.
| | - X Han
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Jiangsu Diabetes Center, Nanjing Medical University, Nanjing, 210029, Jiangsu, China.
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Hajmrle C, Smith N, Spigelman AF, Dai X, Senior L, Bautista A, Ferdaoussi M, MacDonald PE. Interleukin-1 signaling contributes to acute islet compensation. JCI Insight 2016; 1:e86055. [PMID: 27699257 DOI: 10.1172/jci.insight.86055] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
IL-1β is a well-established inducer of both insulin resistance and impaired pancreatic islet function. Despite this, findings examining IL-1 receptor deficiency or antagonism in in vivo animal models, as well as in clinical studies of type 2 diabetic (T2D) patients, have led to conflicting results, suggesting that the actions of IL-1β on glycemic control may be pleiotropic in nature. In the present work, we find that the ability of IL-1β to amplify glucose-stimulated insulin secretion from human islets correlates with donor BMI. Islets from obese donors are sensitized to the insulinotropic effects of this cytokine, whereas the stimulatory effects of IL-1β are lost in islets from obese T2D patients, suggesting a role for IL-1 signaling in islet compensation. Indeed, mice deficient in IL-1 receptor type I become glucose intolerant more rapidly than their WT littermates and have impaired secretory responses during the acute stages of inflammatory and metabolic stress induced by LPS and high-fat diet, respectively. IL-1β directly enhances β cell insulin secretion by increasing granule docking and soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) complex formation at the plasma membrane. Together, our study highlights the importance of IL-1β signaling in islet compensation to metabolic and inflammatory stress.
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20
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Affiliation(s)
- Piero Marchetti
- Department of Clinical and Experimental Medicine, Cisanello University Hospital, University of Pisa, Via Paradisa 2, 56124, Pisa, Italy.
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21
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Hong K, Xu G, Grayson TB, Shalev A. Cytokines Regulate β-Cell Thioredoxin-interacting Protein (TXNIP) via Distinct Mechanisms and Pathways. J Biol Chem 2016; 291:8428-39. [PMID: 26858253 DOI: 10.1074/jbc.m115.698365] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Indexed: 11/06/2022] Open
Abstract
Thioredoxin-interacting protein (TXNIP) is a key regulator of diabetic β-cell apoptosis and dysfunction, and TXNIP inhibition prevents diabetes in mouse models of type 1 and type 2 diabetes. Although we have previously shown that TXNIP is strongly induced by glucose, any regulation by the proinflammatory cytokines tumor necrosis factor α (TNFα), interleukin-1β (IL-1β), and interferon γ (IFNγ) has remained largely unexplored. Moreover, even though this three-cytokine mixture is widely used to mimic type 1 diabetes in vitro, the mechanisms involved are not fully understood. Interestingly, we have now found that this cytokine mixture increases β-cell TXNIP expression; however, although TNFα had no effect, IL-1β surprisingly down-regulated TXNIP transcription, whereas IFNγ increased TXNIP levels in INS-1 β-cells and primary islets. Human TXNIP promoter analyses and chromatin immunoprecipitation studies revealed that the IL-1β effect was mediated by inhibition of carbohydrate response element binding protein activity. In contrast, IFNγ increased pro-apoptotic TXNIP post-transcriptionally via induction of endoplasmic reticulum stress, activation of inositol-requiring enzyme 1α (IRE1α), and suppression of miR-17, a microRNA that targets and down-regulates TXNIP. In fact, miR-17 knockdown was able to mimic the IFNγ effects on TXNIP, whereas miR-17 overexpression blunted the cytokine effect. Thus, our results demonstrate for the first time that the proinflammatory cytokines TNFα, IL-1β, and IFNγ each have distinct and in part opposing effects on β-cell TXNIP expression. These findings thereby provide new mechanistic insight into the regulation of TXNIP and β-cell biology and reveal novel links between proinflammatory cytokines, carbohydrate response element binding protein-mediated transcription, and microRNA signaling.
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Affiliation(s)
- Kyunghee Hong
- From the Comprehensive Diabetes Center and Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Guanlan Xu
- From the Comprehensive Diabetes Center and Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Truman B Grayson
- From the Comprehensive Diabetes Center and Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Anath Shalev
- From the Comprehensive Diabetes Center and Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
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Nunemaker CS. Considerations for Defining Cytokine Dose, Duration, and Milieu That Are Appropriate for Modeling Chronic Low-Grade Inflammation in Type 2 Diabetes. J Diabetes Res 2016; 2016:2846570. [PMID: 27843953 PMCID: PMC5097812 DOI: 10.1155/2016/2846570] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/25/2016] [Indexed: 02/07/2023] Open
Abstract
Proinflammatory cytokines have been implicated in the pathophysiology of both type 1 diabetes (T1D) and type 2 diabetes (T2D). T1D is an autoimmune disease involving the adaptive immune system responding to pancreatic beta-cells as antigen-presenting cells. This attracts immune cells that surround pancreatic islets (insulitis) and secrete cytokines, such as IL-1beta, IFN-gamma, and TNF-alpha, in close proximity to pancreatic beta-cells. In contrast, there is little evidence for such a focused autoimmune response in T2D. Instead, the innate immune system, which responds to cellular damage and pathogens, appears to play a key role. There are three major sources of proinflammatory cytokines that may impact islet/beta-cell function in T2D: (1) from islet cells, (2) from increased numbers of intraislet macrophages/immune cells, and (3) from increased circulating levels of proinflammatory cytokines due to obesity, presumably coming from inflamed adipose tissue. These differences between T1D and T2D are reflected by significant differences in the cytokine concentration, duration, and milieu. This review focuses on chronic versus acute cytokine action, cytokine concentrations, and cytokine milieu from the perspective of the pancreatic islet in T2D. We conclude that new cytokine models may be needed to reflect the pathophysiology of T2D more effectively than what are currently employed.
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Affiliation(s)
- Craig S. Nunemaker
- Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
- *Craig S. Nunemaker:
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Arous C, Halban PA. The skeleton in the closet: actin cytoskeletal remodeling in β-cell function. Am J Physiol Endocrinol Metab 2015; 309:E611-20. [PMID: 26286869 DOI: 10.1152/ajpendo.00268.2015] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 08/11/2015] [Indexed: 01/13/2023]
Abstract
Over the last few decades, biomedical research has considered not only the function of single cells but also the importance of the physical environment within a whole tissue, including cell-cell and cell-extracellular matrix interactions. Cytoskeleton organization and focal adhesions are crucial sensors for cells that enable them to rapidly communicate with the physical extracellular environment in response to extracellular stimuli, ensuring proper function and adaptation. The involvement of the microtubular-microfilamentous cytoskeleton in secretion mechanisms was proposed almost 50 years ago, since when the evolution of ever more sensitive and sophisticated methods in microscopy and in cell and molecular biology have led us to become aware of the importance of cytoskeleton remodeling for cell shape regulation and its crucial link with signaling pathways leading to β-cell function. Emerging evidence suggests that dysfunction of cytoskeletal components or extracellular matrix modification influences a number of disorders through potential actin cytoskeleton disruption that could be involved in the initiation of multiple cellular functions. Perturbation of β-cell actin cytoskeleton remodeling could arise secondarily to islet inflammation and fibrosis, possibly accounting in part for impaired β-cell function in type 2 diabetes. This review focuses on the role of actin remodeling in insulin secretion mechanisms and its close relationship with focal adhesions and myosin II.
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Affiliation(s)
- Caroline Arous
- Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland
| | - Philippe A Halban
- Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland
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24
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Morris DL. Minireview: Emerging Concepts in Islet Macrophage Biology in Type 2 Diabetes. Mol Endocrinol 2015; 29:946-62. [PMID: 26001058 DOI: 10.1210/me.2014-1393] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Chronic systemic inflammation is a hallmark feature of obesity and type 2 diabetes. Both resident and recruited islet macrophages contribute to the proinflammatory milieu of the diabetic islet. However, macrophages also appear to be critical for β-cell formation during development and support β-cell replication in experimental models of pancreas regeneration. In light of these findings, perhaps macrophages in the islet need to be viewed more as a fulcrum where deleterious inflammatory activation is balanced with beneficial tissue repair processes. Undoubtedly, defining the factors that contribute to the ontogeny, heterogeneity, and functionality of macrophages in normal, diseased, and regenerating islets will be necessary to determine whether that fulcrum can be moved to preserve functional β-cell mass in persons with diabetes. The intent of this review is to introduce the reader to emerging concepts of islet macrophage biology that may challenge the perception that macrophage accumulation in islets is merely a pathological feature of type 2 diabetes.
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Affiliation(s)
- David L Morris
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202
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