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Ding M, Fang QH, Cui YT, Shen QL, Liu Q, Wang PH, Yu DM, Li CJ. Liraglutide prevents β-cell apoptosis via inactivation of NOX2 and its related signaling pathway. J Diabetes Complications 2019; 33:267-277. [PMID: 30772113 DOI: 10.1016/j.jdiacomp.2018.12.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/20/2018] [Accepted: 12/26/2018] [Indexed: 01/01/2023]
Abstract
AIMS High glucose (HG)-induced pancreatic β-cell apoptosis may be a major contributor to the progression of diabetes mellitus (DM). NADPH oxidase (NOX2) has been considered a crucial regulator in β-cell apoptosis. This study was designed to evaluate the impact of GLP-1 receptor agonist (GLP-1Ra) liraglutide on pancreatic β-cell apoptosis in diabetes and the underlying mechanisms involved. METHODS The diabetic rat models induced by streptozotocin (STZ) and a high fat diet (HFD) received 12 weeks of liraglutide treatment. Hyperglycemic clamp test was carried out to evaluate β-cell function in vivo. Flow cytometry analysis was used to measure apoptosis rates in vitro. DCFH-DA method was used to detected ROS level in vivo and in vitro. RESULTS Liraglutide significantly improved islet function and morphology in diabetic rats and decreased cell apoptosis rates. Thr183/Thr185 p-JNK1/2 and NOX2 levels reduced in diabetic rats and HG-induced INS-1 cell following liraglutide treatment. In addition, liraglutide upregulated the phosphorylation of AMPKα (p-AMPKα), which prevented NOX2 activation and alleviated HG-induced β-cell apoptosis. CONCLUSION The p-AMPKα/NOX2/JNK1/2 pathway is essential for liraglutide to attenuate HG-induced β-cell apoptosis, which further proves that GLP-1Ras may become promising therapeutics for diabetes mellitus.
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Affiliation(s)
- Min Ding
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Qian-Hua Fang
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Yuan-Tao Cui
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Qi-Ling Shen
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Qian Liu
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Peng-Hua Wang
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - De-Min Yu
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China.
| | - Chun-Jun Li
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China.
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Memory-like Liver Natural Killer Cells are Responsible for Islet Destruction in Secondary Islet Transplantation. Sci Rep 2019; 9:1022. [PMID: 30705364 PMCID: PMC6355863 DOI: 10.1038/s41598-018-37395-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 12/06/2018] [Indexed: 12/13/2022] Open
Abstract
We previously demonstrated the pivotal role of natural killer (NK) cells in islet graft loss during the early phase after intraportal syngeneic islet transplantation (IT). Liver-resident DX5- NK cells were reported to possess memory-like properties, distinguishing them from conventional DX5+ NK cells. Here, we investigated the impact of primary IT-induced liver DX5- NK cells on the engraftment of secondary-transplanted islets in mice. The culture of liver NK cells isolated from naive mice with TNF-α, IFN-γ, and IL-lβ, mimicking instant blood-mediated inflammatory reaction, led to significantly increased DX5- NK cell percentage among total liver NK cells. Consistently, the prolonged expansion of DX5- CD69+ TRAIL+ CXCR3+ NK cells was observed after intraportal IT of 300 syngeneic islets (marginal mass). In most diabetic mice, 400 syngeneic islets of primary IT were sufficient to achieve normoglycaemia, whereas the same mass after secondary IT failed to induce normoglycaemia in mice that received 200 syngeneic islets during primary IT. These findings indicated that liver-resident DX5- NK cells significantly expanded even after syngeneic IT, and that these memory-like NK cells may target both originally engrafted and secondary-transplanted islets. Furthermore, anti-TNF-α treatment suppressed the expansion of liver-resident DX5- NK cells, resulting in successful islet engraftment after sequential ITs.
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Chen J, Stimpson SE, Fernandez-Bueno GA, Mathews CE. Mitochondrial Reactive Oxygen Species and Type 1 Diabetes. Antioxid Redox Signal 2018; 29:1361-1372. [PMID: 29295631 PMCID: PMC6166689 DOI: 10.1089/ars.2017.7346] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
SIGNIFICANCE The complex etiology of type 1 diabetes (T1D) is the outcome of failures in regulating immunity in combination with beta cell perturbations. Mitochondrial dysfunction in beta cells and immune cells may be involved in T1D pathogenesis. Mitochondrial energy production is essential for the major task of beta cells (the secretion of insulin in response to glucose). Mitochondria are a major site of reactive oxygen species (ROS) production. Under immune attack, mitochondrial ROS (mtROS) participate in beta cell damage. Similarly, T cell fate during immune responses is tightly regulated by mitochondrial physiology, morphology, and metabolism. Production of mtROS is essential for signaling in antigen-specific T cell activation. Mitochondrial dysfunction in T cells has been noted as a feature of some human autoimmune diseases. Recent Advances: Preclinical and clinical studies indicate that mitochondrial dysfunction in beta cells sensitizes these cells to immune-mediated destruction via direct or indirect mechanisms. Sensitivity of beta cells to mtROS is associated with genetic T1D risk loci in human and the T1D-prone nonobese diabetic (NOD) mouse. Mitochondrial dysfunction and altered metabolism have also been observed in immune cells of NOD mice and patients with T1D. This immune cell mitochondrial dysfunction has been linked to deleterious functional changes. CRITICAL ISSUES It remains unclear how mitochondria control T cell receptor signaling and downstream events, including calcium flux and activation of transcription factors during autoimmunity. FUTURE DIRECTIONS Mechanistic studies are needed to investigate the mitochondrial pathways involved in autoimmunity, including T1D. These studies should seek to identify the role of mitochondria in regulating innate and adaptive immune cell activity and beta cell failure.
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Affiliation(s)
- Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
| | - Scott E Stimpson
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
| | - Gabriel A Fernandez-Bueno
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
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Oleson BJ, Corbett JA. Dual Role of Nitric Oxide in Regulating the Response of β Cells to DNA Damage. Antioxid Redox Signal 2018; 29:1432-1445. [PMID: 28978225 PMCID: PMC6166691 DOI: 10.1089/ars.2017.7351] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 09/09/2017] [Indexed: 01/09/2023]
Abstract
SIGNIFICANCE Cytokines released in and around pancreatic islets during islet inflammation are believed to contribute to impaired β cell function and β cell death during the development of diabetes. Nitric oxide, produced by β cells in response to cytokine exposure, controls many of the responses of β cells during islet inflammation. Recent Advances: Although nitric oxide has been shown to inhibit insulin secretion and oxidative metabolism and induce DNA damage in β cells, it also activates protective pathways that promote recovery of insulin secretion and oxidative metabolism and repair of damaged DNA. Recent studies have identified a novel role for nitric oxide in selectively regulating the DNA damage response in β cells. CRITICAL ISSUES Does nitric oxide mediate cytokine-induced β cell damage, or is nitric oxide produced by β cells in response to cytokines to protect β cells from damage? FUTURE DIRECTIONS β cells appear to be the only islet endocrine cell type capable of responding to proinflammatory cytokines with the production of nitric oxide, and these terminally differentiated cells have a limited capacity to regenerate. It is likely that there is a physiological purpose for this response, and understanding this could open new areas of study regarding the loss of functional β cell mass during diabetes development.
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Affiliation(s)
- Bryndon J. Oleson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - John A. Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
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Burg AR, Tse HM. Redox-Sensitive Innate Immune Pathways During Macrophage Activation in Type 1 Diabetes. Antioxid Redox Signal 2018; 29:1373-1398. [PMID: 29037052 PMCID: PMC6166692 DOI: 10.1089/ars.2017.7243] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
SIGNIFICANCE Type 1 diabetes (T1D) is an autoimmune disease resulting in β-cell destruction mediated by islet-infiltrating leukocytes. The role of oxidative stress in human and murine models of T1D is highly significant as these noxious molecules contribute to diabetic complications and β-cell lysis, but their direct impact on dysregulated autoimmune responses is highly understudied. Pro-inflammatory macrophages play a vital role in the initiation and effector phases of T1D by producing free radicals and pro-inflammatory cytokines to facilitate β-cell destruction and to present antigen to autoreactive T cells. Recent Advances: Redox modulation of macrophage functions may play critical roles in autoimmunity. These include enhancing pro-inflammatory innate immune signaling pathways in response to environmental triggers, enforcing an M1 macrophage differentiation program, controlling antigen processing, and altering peptide recognition by oxidative post-translational modification. Therefore, an oxidative environment may act on multiple macrophage functions to orchestrate T1D pathogenesis. CRITICAL ISSUES Mechanisms involved in the initiation of T1D remain unclear, making preventive and early therapeutics difficult to develop. Although many of these advances in the redox regulation of macrophages are in their infancy, they provide insight into how oxidative stress aids in the precipitating event of autoimmune activation. FUTURE DIRECTIONS Future studies should be aimed at mechanistically determining which redox-regulated macrophage functions are pertinent in T1D pathogenesis, as well as at investigating potential targetable therapeutics to halt and/or dampen innate immune activation in T1D.
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Affiliation(s)
- Ashley R Burg
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham , Birmingham, Alabama
| | - Hubert M Tse
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham , Birmingham, Alabama
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Wang X, Xi W, Qin J, Lv J, Wang Y, Zhang T, Li SJ. Deficiency of voltage-gated proton channel Hv1 attenuates streptozotocin-induced β-cell damage. Biochem Biophys Res Commun 2018; 498:975-980. [DOI: 10.1016/j.bbrc.2018.03.092] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 03/13/2018] [Indexed: 10/17/2022]
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Das UN. Is There a Role for Bioactive Lipids in the Pathobiology of Diabetes Mellitus? Front Endocrinol (Lausanne) 2017; 8:182. [PMID: 28824543 PMCID: PMC5539435 DOI: 10.3389/fendo.2017.00182] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/10/2017] [Indexed: 12/12/2022] Open
Abstract
Inflammation, decreased levels of circulating endothelial nitric oxide (eNO) and brain-derived neurotrophic factor (BDNF), altered activity of hypothalamic neurotransmitters (including serotonin and vagal tone) and gut hormones, increased concentrations of free radicals, and imbalance in the levels of bioactive lipids and their pro- and anti-inflammatory metabolites have been suggested to play a role in diabetes mellitus (DM). Type 1 diabetes mellitus (type 1 DM) is due to autoimmune destruction of pancreatic β cells because of enhanced production of IL-6 and tumor necrosis factor-α (TNF-α) and other pro-inflammatory cytokines released by immunocytes infiltrating the pancreas in response to unknown exogenous and endogenous toxin(s). On the other hand, type 2 DM is due to increased peripheral insulin resistance secondary to enhanced production of IL-6 and TNF-α in response to high-fat and/or calorie-rich diet (rich in saturated and trans fats). Type 2 DM is also associated with significant alterations in the production and action of hypothalamic neurotransmitters, eNO, BDNF, free radicals, gut hormones, and vagus nerve activity. Thus, type 1 DM is because of excess production of pro-inflammatory cytokines close to β cells, whereas type 2 DM is due to excess of pro-inflammatory cytokines in the systemic circulation. Hence, methods designed to suppress excess production of pro-inflammatory cytokines may form a new approach to prevent both type 1 and type 2 DM. Roux-en-Y gastric bypass and similar surgeries ameliorate type 2 DM, partly by restoring to normal: gut hormones, hypothalamic neurotransmitters, eNO, vagal activity, gut microbiota, bioactive lipids, BDNF production in the gut and hypothalamus, concentrations of cytokines and free radicals that results in resetting glucose-stimulated insulin production by pancreatic β cells. Our recent studies suggested that bioactive lipids, such as arachidonic acid, eicosapentaneoic acid, and docosahexaenoic acid (which are unsaturated fatty acids) and their anti-inflammatory metabolites: lipoxin A4, resolvins, protectins, and maresins, may have antidiabetic actions. These bioactive lipids have anti-inflammatory actions, enhance eNO, BDNF production, restore hypothalamic dysfunction, enhance vagal tone, modulate production and action of ghrelin, leptin and adiponectin, and influence gut microbiota that may explain their antidiabetic action. These pieces of evidence suggest that methods designed to selectively deliver bioactive lipids to pancreatic β cells, gut, liver, and muscle may prevent type 1 and type 2 DM.
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Affiliation(s)
- Undurti N. Das
- BioScience Research Centre, Department of Medicine, Gayatri Vidya Parishad Hospital, GVP College of Engineering Campus, Visakhapatnam, India
- UND Life Sciences, Battle Ground, WA, United States
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Zhang J, Chen Z, Zhou Z, Yang P, Wang CY. Sumoylation Modulates the Susceptibility to Type 1 Diabetes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 963:299-322. [DOI: 10.1007/978-3-319-50044-7_18] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Gusdon AM, Fernandez-Bueno GA, Wohlgemuth S, Fernandez J, Chen J, Mathews CE. Respiration and substrate transport rates as well as reactive oxygen species production distinguish mitochondria from brain and liver. BMC BIOCHEMISTRY 2015; 16:22. [PMID: 26358560 PMCID: PMC4564979 DOI: 10.1186/s12858-015-0051-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 09/02/2015] [Indexed: 12/04/2022]
Abstract
BACKGROUND Aberrant mitochondrial function, including excessive reactive oxygen species (ROS) production, has been implicated in the pathogenesis of human diseases. The use of mitochondrial inhibitors to ascertain the sites in the electron transport chain (ETC) resulting in altered ROS production can be an important tool. However, the response of mouse mitochondria to ETC inhibitors has not been thoroughly assessed. Here we set out to characterize the differences in phenotypic response to ETC inhibitors between the more energetically demanding brain mitochondria and less energetically demanding liver mitochondria in commonly utilized C57BL/6J mice. RESULTS We show that in contrast to brain mitochondria, inhibiting distally within complex I or within complex III does not increase liver mitochondrial ROS production supported by complex I substrates, and liver mitochondrial ROS production supported by complex II substrates occurred primarily independent of membrane potential. Complex I, II, and III enzymatic activities and membrane potential were equivalent between liver and brain and responded to ETC. inhibitors similarly. Brain mitochondria exhibited an approximately two-fold increase in complex I and II supported respiration compared with liver mitochondria while exhibiting similar responses to inhibitors. Elevated NADH transport and heightened complex II-III coupled activity accounted for increased complex I and II supported respiration, respectively in brain mitochondria. CONCLUSIONS We conclude that important mechanistic differences exist between mouse liver and brain mitochondria and that mouse mitochondria exhibit phenotypic differences compared with mitochondria from other species.
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Affiliation(s)
- Aaron M Gusdon
- Department of Pathology, Immunology, and Laboratory Medicine, The University of Florida College of Medicine, Gainesville, FL, 32610, USA.
- Department of Neurology, Weill Cornell Medical Center/NewYork-Presbyterian Hospital, New York, NY, 10065, USA.
| | - Gabriel A Fernandez-Bueno
- Department of Pathology, Immunology, and Laboratory Medicine, The University of Florida College of Medicine, Gainesville, FL, 32610, USA.
| | - Stephanie Wohlgemuth
- Department of Animal Sciences, Institute of Food and Agricultural Sciences, The University of Florida, Gainesville, FL, 32610, USA.
| | - Jenelle Fernandez
- Department of Pathology, Immunology, and Laboratory Medicine, The University of Florida College of Medicine, Gainesville, FL, 32610, USA.
| | - Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, The University of Florida College of Medicine, Gainesville, FL, 32610, USA.
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, The University of Florida College of Medicine, Gainesville, FL, 32610, USA.
- , Present address: 1275 Center Dr, Room J597, P.O. Box 100275, Gainesville, FL, 32610-0275, USA.
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Oleson BJ, McGraw JA, Broniowska KA, Annamalai M, Chen J, Bushkofsky JR, Davis DB, Corbett JA, Mathews CE. Distinct differences in the responses of the human pancreatic β-cell line EndoC-βH1 and human islets to proinflammatory cytokines. Am J Physiol Regul Integr Comp Physiol 2015; 309:R525-34. [PMID: 26084699 DOI: 10.1152/ajpregu.00544.2014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 06/15/2015] [Indexed: 11/22/2022]
Abstract
While insulinoma cells have been developed and proven to be extremely useful in studies focused on mechanisms controlling β-cell function and viability, translating findings to human β-cells has proven difficult because of the limited access to human islets and the absence of suitable insulinoma cell lines of human origin. Recently, a human β-cell line, EndoC-βH1, has been derived from human fetal pancreatic buds. The purpose of this study was to determine whether human EndoC-βH1 cells respond to cytokines in a fashion comparable to human islets. Unlike most rodent-derived insulinoma cell lines that respond to cytokines in a manner consistent with rodent islets, EndoC-βH1 cells fail to respond to a combination of cytokines (IL-1, IFN-γ, and TNF) in a manner consistent with human islets. Nitric oxide, produced following inducible nitric oxide synthase (iNOS) expression, is a major mediator of cytokine-induced human islet cell damage. We show that EndoC-βH1 cells fail to express iNOS or produce nitric oxide in response to this combination of cytokines. Inhibitors of iNOS prevent cytokine-induced loss of human islet cell viability; however, they do not prevent cytokine-induced EndoC-βH1 cell death. Stressed human islets or human islets expressing heat shock protein 70 (HSP70) are resistant to cytokines, and, much like stressed human islets, EndoC-βH1 cells express HSP70 under basal conditions. Elevated basal expression of HSP70 in EndoC-βH1 cells is consistent with the lack of iNOS expression in response to cytokine treatment. While expressing HSP70, EndoC-βH1 cells fail to respond to endoplasmic reticulum stress activators, such as thapsigargin. These findings indicate that EndoC-βH1 cells do not faithfully recapitulate the response of human islets to cytokines. Therefore, caution should be exercised when making conclusions regarding the actions of cytokines on human islets when using this human-derived insulinoma cell line.
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Affiliation(s)
- Bryndon J Oleson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Jennifer A McGraw
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | | | - Mani Annamalai
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| | - Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| | - Justin R Bushkofsky
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin, Madison, Wisconsin; and
| | - Dawn B Davis
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin, Madison, Wisconsin; and William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin;
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
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Broniowska KA, Oleson BJ, McGraw J, Naatz A, Mathews CE, Corbett JA. How the location of superoxide generation influences the β-cell response to nitric oxide. J Biol Chem 2015; 290:7952-60. [PMID: 25648890 DOI: 10.1074/jbc.m114.627869] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cytokines impair the function and decrease the viability of insulin-producing β-cells by a pathway that requires the expression of inducible nitric oxide synthase (iNOS) and generation of high levels of nitric oxide. In addition to nitric oxide, excessive formation of reactive oxygen species, such as superoxide and hydrogen peroxide, has been shown to cause β-cell damage. Although the reaction of nitric oxide with superoxide results in the formation of peroxynitrite, we have shown that β-cells do not have the capacity to produce this powerful oxidant in response to cytokines. When β-cells are forced to generate peroxynitrite using nitric oxide donors and superoxide-generating redox cycling agents, superoxide scavenges nitric oxide and prevents the inhibitory and destructive actions of nitric oxide on mitochondrial oxidative metabolism and β-cell viability. In this study, we show that the β-cell response to nitric oxide is regulated by the location of superoxide generation. Nitric oxide freely diffuses through cell membranes, and it reacts with superoxide produced within cells and in the extracellular space, generating peroxynitrite. However, only when it is produced within cells does superoxide attenuate nitric oxide-induced mitochondrial dysfunction, gene expression, and toxicity. These findings suggest that the location of radical generation and the site of radical reactions are key determinants in the functional response of β-cells to reactive oxygen species and reactive nitrogen species. Although nitric oxide is freely diffusible, its biological function can be controlled by the local generation of superoxide, such that when this reaction occurs within β-cells, superoxide protects β-cells by scavenging nitric oxide.
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Affiliation(s)
- Katarzyna A Broniowska
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and
| | - Bryndon J Oleson
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and
| | - Jennifer McGraw
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and
| | - Aaron Naatz
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and
| | - Clayton E Mathews
- the Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, Florida 32610
| | - John A Corbett
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and
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Herold Z, Nagy P, Patócs A, Somogyi A. [The role of chromogranin-A and its derived peptide, WE-14 in the development of type 1 diabetes mellitus]. Orv Hetil 2015; 156:163-70. [PMID: 25618857 DOI: 10.1556/oh.2015.30087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Chromogranin-A is a member of the granine protein family. It is produced in neuroendocrine cells via secretory granules. Many cleavage proteins are formed from chromogranin-A, from which some have well known biological activity, while the function of others is not yet fully known. Serum chromogranin-A levels are used in neuroendocrine tumour diagnostics. Recent studies showed that one of its cleavage protein, WE-14 may also play a role in the development of type 1 diabetes. WE-14 may function as an autoantigen for T-cells involved in the destruction of β-cells. This mechanism was previously observed only in non-obese diabetic mice. Novel results show that WE-14 also serves as a target for autoreactive cells in newly diagnosed type 1 diabetic patients as well, which reaction can be increased with transglutaminase. In this paper the authors summarize the recent knowledge about chromogranin-A and its potential role in the pathomechanism of type 1 diabetes mellitus.
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Affiliation(s)
- Zoltán Herold
- Szent István Egyetem Állatorvos-tudományi Kar Budapest Semmelweis Egyetem, Általános Orvostudományi Kar II. Belgyógyászati Klinika Budapest Szentkirályi utca 46. 1088
| | - Péter Nagy
- Semmelweis Egyetem, Általános Orvostudományi Kar I. Patológiai és Kísérleti Rákkutató Intézet Budapest
| | - Attila Patócs
- Semmelweis Egyetem, Általános Orvostudományi Kar Laboratóriumi Medicina Intézet Budapest MTA-SE "Lendület" Örökletes Endokrin Daganatok Kutatócsoport Budapest
| | - Anikó Somogyi
- Semmelweis Egyetem, Általános Orvostudományi Kar II. Belgyógyászati Klinika Budapest Szentkirályi utca 46. 1088
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Mahmoud AM, Ahmed OM, Ashour MB, Abdel-Moneim A. In vivo and in vitro antidiabetic effects of citrus flavonoids; a study on the mechanism of action. Int J Diabetes Dev Ctries 2015. [DOI: 10.1007/s13410-014-0268-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Sleem M, Taye A, El-Moselhy MA, Mangoura SA. Combination therapy with losartan and l-carnitine protects against endothelial dysfunction of streptozotocin-induced diabetic rats. Eur J Pharmacol 2014; 744:10-7. [DOI: 10.1016/j.ejphar.2014.09.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 09/17/2014] [Accepted: 09/18/2014] [Indexed: 12/24/2022]
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15
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Broniowska KA, Mathews CE, Corbett JA. Do β-cells generate peroxynitrite in response to cytokine treatment? J Biol Chem 2013; 288:36567-78. [PMID: 24194521 DOI: 10.1074/jbc.m113.522243] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The purpose of this study was to determine the reactive species that is responsible for cytokine-mediated β-cell death. Inhibitors of inducible nitric oxide synthase prevent this death, and addition of exogenous nitric oxide using donors induces β-cell death. The reaction of nitric oxide with superoxide results in the generation of peroxynitrite, and this powerful oxidant has been suggested to be the mediator of β-cell death in response to cytokine treatment. Recently, coumarin-7-boronate has been developed as a probe for the selective detection of peroxynitrite. Using this reagent, we show that addition of the NADPH oxidase activator phorbol 12-myristate 13-acetate to nitric oxide-producing macrophages results in peroxynitrite generation. Using a similar approach, we demonstrate that cytokines fail to stimulate peroxynitrite generation by rat islets and insulinoma cells, either with or without phorbol 12-myristate 13-acetate treatment. When forced to produce superoxide using redox cyclers, this generation is associated with protection from nitric oxide toxicity. These findings indicate that: (i) nitric oxide is the likely mediator of the toxic effects of cytokines, (ii) β-cells do not produce peroxynitrite in response to cytokines, and (iii) when forced to produce superoxide, the scavenging of nitric oxide by superoxide is associated with protection of β-cells from nitric oxide-mediated toxicity.
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Affiliation(s)
- Katarzyna A Broniowska
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and
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Leiter EH, Schile A. Genetic and Pharmacologic Models for Type 1 Diabetes. CURRENT PROTOCOLS IN MOUSE BIOLOGY 2013; 3:9-19. [PMID: 24592352 PMCID: PMC3936677 DOI: 10.1002/9780470942390.mo120154] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Type 1 diabetes (T1D) is characterized by a partial or total insufficiency of insulin. The premiere animal model of autoimmune T cell-mediated T1D is the NOD mouse. A dominant negative mutation in the mouse insulin 2 gene (Ins2Akita ) produces a severe insulin deficiency syndrome without autoimmune involvement, as do a variety of transgenes overexpressed in beta cells. Pharmacologically-induced T1D (without autoimmunity) elicted by alloxan or streptozotocin at high doses can generate hyperglycemia in almost any strain of mouse by direct toxicity. Multiple low doses of streptozotocin combine direct beta cell toxicity with local inflammation to elicit T1D in a male sex-specific fashion. A summary of protocols relevant to the management of these different mouse models will be covered in this overview.
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Affiliation(s)
- Edward H. Leiter
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, Tel: 207-288-6370, FAX: 207-288-6077
| | - Andrew Schile
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, Tel: 207-288-6370, FAX: 207-288-6077
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Padgett LE, Broniowska KA, Hansen PA, Corbett JA, Tse HM. The role of reactive oxygen species and proinflammatory cytokines in type 1 diabetes pathogenesis. Ann N Y Acad Sci 2013; 1281:16-35. [PMID: 23323860 PMCID: PMC3715103 DOI: 10.1111/j.1749-6632.2012.06826.x] [Citation(s) in RCA: 192] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Type 1 diabetes (T1D) is a T cell–mediated autoimmune disease characterized by the destruction of insulin-secreting pancreatic β cells. In humans with T1D and in nonobese diabetic (NOD) mice (a murine model for human T1D), autoreactive T cells cause β-cell destruction, as transfer or deletion of these cells induces or prevents disease, respectively. CD4+ and CD8+ T cells use distinct effector mechanisms and act at different stages throughout T1D to fuel pancreatic β-cell destruction and disease pathogenesis. While these adaptive immune cells employ distinct mechanisms for β-cell destruction, one central means for enhancing their autoreactivity is by the secretion of proinflammatory cytokines, such as IFN-γ, TNF-α, and IL-1. In addition to their production by diabetogenic T cells, proinflammatory cytokines are induced by reactive oxygen species (ROS) via redox-dependent signaling pathways. Highly reactive molecules, proinflammatory cytokines are produced upon lymphocyte infiltration into pancreatic islets and induce disease pathogenicity by directly killing β cells, which characteristically possess low levels of antioxidant defense enzymes. In addition to β-cell destruction, proinflammatory cytokines are necessary for efficient adaptive immune maturation, and in the context of T1D they exacerbate autoimmunity by intensifying adaptive immune responses. The first half of this review discusses the mechanisms by which autoreactive T cells induce T1D pathogenesis and the importance of ROS for efficient adaptive immune activation, which, in the context of T1D, exacerbates autoimmunity. The second half provides a comprehensive and detailed analysis of (1) the mechanisms by which cytokines such as IL-1 and IFN-γ influence islet insulin secretion and apoptosis and (2) the key free radicals and transcription factors that control these processes.
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Affiliation(s)
- Lindsey E Padgett
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Li R, Liang T, Xu L, Li Y, Zhang S, Duan X. Protective effect of cinnamon polyphenols against STZ-diabetic mice fed high-sugar, high-fat diet and its underlying mechanism. Food Chem Toxicol 2013; 51:419-25. [DOI: 10.1016/j.fct.2012.10.024] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 10/20/2012] [Accepted: 10/22/2012] [Indexed: 12/28/2022]
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Driver JP, Chen YG, Mathews CE. Comparative genetics: synergizing human and NOD mouse studies for identifying genetic causation of type 1 diabetes. Rev Diabet Stud 2012; 9:169-87. [PMID: 23804259 DOI: 10.1900/rds.2012.9.169] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Although once widely anticipated to unlock how human type 1 diabetes (T1D) develops, extensive study of the nonobese diabetic (NOD) mouse has failed to yield effective treatments for patients with the disease. This has led many to question the usefulness of this animal model. While criticism about the differences between NOD and human T1D is legitimate, in many cases disease in both species results from perturbations modulated by the same genes or different genes that function within the same biological pathways. Like in humans, unusual polymorphisms within an MHC class II molecule contributes the most T1D risk in NOD mice. This insight supports the validity of this model and suggests the NOD has been improperly utilized to study how to cure or prevent disease in patients. Indeed, clinical trials are far from administering T1D therapeutics to humans at the same concentration ranges and pathological states that inhibit disease in NOD mice. Until these obstacles are overcome it is premature to label the NOD mouse a poor surrogate to test agents that cure or prevent T1D. An additional criticism of the NOD mouse is the past difficulty in identifying genes underlying T1D using conventional mapping studies. However, most of the few diabetogenic alleles identified to date appear relevant to the human disorder. This suggests that rather than abandoning genetic studies in NOD mice, future efforts should focus on improving the efficiency with which diabetes susceptibility genes are detected. The current review highlights why the NOD mouse remains a relevant and valuable tool to understand the genes and their interactions that promote autoimmune diabetes and therapeutics that inhibit this disease. It also describes a new range of technologies that will likely transform how the NOD mouse is used to uncover the genetic causes of T1D for years to come.
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Affiliation(s)
- John P Driver
- Department of Animal Science, University of Florida, Gainesville, FL 32610, USA
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Bobbala D, Chen XL, Leblanc C, Mayhue M, Stankova J, Tanaka T, Chen YG, Ilangumaran S, Ramanathan S. Interleukin-15 plays an essential role in the pathogenesis of autoimmune diabetes in the NOD mouse. Diabetologia 2012; 55:3010-20. [PMID: 22890824 DOI: 10.1007/s00125-012-2675-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 07/05/2012] [Indexed: 12/21/2022]
Abstract
AIMS/HYPOTHESIS IL-15, induced by innate immune stimuli, promotes rheumatoid arthritis and inflammatory bowel disease. However, its role in autoimmune type 1 diabetes is unclear. Our aim is to define the role of IL-15 in the pathogenesis of diabetes in the NOD mouse model. METHODS We generated NOD.Il15(-/-) mice expressing a polyclonal repertoire of T cell antigen receptor (TCR) or a transgenic TCR and monitored diabetes onset and insulitis. NOD Scid.Il15(-/-) (full name NOD.CB17-Prkdc (scid)/NCrCrl) and NOD Scid.gamma (full name NOD.Cg-Prkdc(scid) Il2rg ( tm1Wjl )/SzJ) mice were used to distinguish the requirement for IL-15 signalling in CD8(+) T cells and antigen-presenting cells (APCs) to induce disease. We examined the effect of blocking IL-15 signalling on diabetes onset in NOD mice. RESULTS At 7 months of age, more than 75% of the NOD Il15(-/-) female mice remained diabetes free compared with only 30% in the control group. Diabetes incidence was also decreased in 8.3-NOD (full name NOD Cg-Tg[TcraTcrbNY8.3]-1Pesa/DvsJ).Il15(-/-) mice expressing a highly pathogenic transgenic TCR on CD8(+) T cells. Adoptive transfer of splenocytes from diabetic NOD and 8.3-NOD donors induced disease in NOD Scid recipients but not in NOD Scid.Il15(-/-) or NOD Scid.gamma mice. Transient blockade of IL-15 signalling at the onset of insulitis prevented diabetes in NOD mice. CONCLUSIONS/INTERPRETATION Our results show that IL-15 is needed for the initial activation of diabetogenic CD8(+) T cells as well as for sustaining the diabetogenic potential of antigen-stimulated cells, acting on both CD8(+) T cells and on APCs. Our findings demonstrate a critical role for IL-15 in the pathogenesis of autoimmune diabetes and suggest that IL-15 is a promising therapeutic target.
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Affiliation(s)
- D Bobbala
- CRC 4855, Immunology Division, Department of Pediatrics, Faculty of Medicine and Health Sciences, 3001 North 12th Avenue, Sherbrooke, Quebec J1H 5N4, Canada
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21
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Abstract
Autoimmune Type 1 A Diabetes (T1D) is characterized by dependence on exogenous insulin consequential to the autoimmune attack and destruction of insulin-producing islet beta cells. Pancreatic islet cell inflammation, or insulitis, precedes beta cell death and T1D onset. In the insulitic lesion, innate immune cells produce chemokines and cytokines that recruit and activate adaptive immune cells (Eizirik D et al., Nat Rev Endocrinol 5:219-226, 2009). Locally produced cytokines not only increase immune surveillance of beta cells (Hanafusa T and Imagawa A, Ann NY Acad Sci 1150:297-299, 2008), but also cause beta cell dysfunction and decreased insulin secretion due to the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) by the beta cells. This, coupled to the high levels of ROS and RNS secreted by activated macrophages and the low antioxidant capacities of beta cells (Huurman VA, PLoS One 3:e2435, 2008; Schatz D, Pediatr Diabetes 5:72-79, 2004; Verge CF, Diabetes 44:1176-1179, 1995), implicates free radicals as important effectors in T1D pathogenesis (Eizirik D et al., Nat Rev Endocrinol 5:219-226, 2009; Hanafusa T and Imagawa A, Ann NY Acad Sci 1150:297-299, 2008; Eisenbarth GS and Jeffrey J, Arq Bras Endocrinol Metabol 52:146-155, 2008; Pietropaolo M et al., Pediatr Diabetes 6:184-192, 2005).
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Affiliation(s)
- Yaíma L Lightfoot
- Department of Pathology, University of Florida College of Medicine, Gainesville, FL, USA
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Thayer TC, Delano M, Liu C, Chen J, Padgett LE, Tse HM, Annamali M, Piganelli JD, Moldawer LL, Mathews CE. Superoxide production by macrophages and T cells is critical for the induction of autoreactivity and type 1 diabetes. Diabetes 2011; 60:2144-51. [PMID: 21715554 PMCID: PMC3142064 DOI: 10.2337/db10-1222] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE The role of reactive oxygen species (ROS) and their dissipation in type 1 diabetes pathogenesis have garnered considerable controversy. Our recent work has demonstrated the importance of NADPH oxidase (NOX) activity for type 1 diabetes development and modulating T-cell autoreactivity. We previously linked decreased monocyte ROS with diabetes resistance in the alloxan-resistant mouse, and NOD-Ncf1(m1J) mice with a genetic ablation of NOX activity had reduced and delayed type 1 diabetes compared with NOD mice. RESEARCH DESIGN AND METHODS To determine the required cellular sources of ROS that are necessary for type 1 diabetes initiation, we used antibody depletion and adoptive transfer experiments into NOD and NOD-Scid females, respectively. After receiving treatment, female mice were monitored for hyperglycemia and overt diabetes. RESULTS Depletion of macrophages and neutrophils fully protected NOD mice from type 1 diabetes. However, elimination of neutrophils alone showed no significant reduction or delay. Type 1 diabetes induction in NOD-Scid mice by adoptive transfer with NOD-Ncf1(m1J) splenocytes was significantly delayed compared with NOD splenocytes, suggesting macrophage ROS and modulation of effector responses are critical for diabetes. The adaptive immune response was also altered by the absence of NOX activity, as purified T cells from NOD-Ncf1(m1J) mice exhibited delayed transfer kinetics. Cotransfer experiments demonstrated the defect was intrinsic to NOX-deficient CD8(+) T cells. After stimulation, cytotoxic T cells exhibited decreased effector function in the absence of superoxide production. CONCLUSIONS These data demonstrate that the impaired autoreactive response of NOX-deficient NOD-Ncf1(m1J) immune system results from an alteration in the antigen-presenting cell-T-cell axis rather than failure of neutrophils to act as effector cells and that ROS signaling is important for the initiation of β-cell-directed autoimmunity by T cells.
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Affiliation(s)
- Terri C. Thayer
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Matthew Delano
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida
| | - Chao Liu
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| | - Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| | - Lindsey E. Padgett
- Department of Microbiology, University of Alabama–Birmingham School of Medicine, Birmingham, Alabama
| | - Hubert M. Tse
- Department of Microbiology, University of Alabama–Birmingham School of Medicine, Birmingham, Alabama
| | - Mani Annamali
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| | - Jon D. Piganelli
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Lyle L. Moldawer
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida
| | - Clayton E. Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
- Corresponding author: Clayton E. Mathews,
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Lightfoot YL, Chen J, Mathews CE. Role of the mitochondria in immune-mediated apoptotic death of the human pancreatic β cell line βLox5. PLoS One 2011; 6:e20617. [PMID: 21738580 PMCID: PMC3124469 DOI: 10.1371/journal.pone.0020617] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 05/07/2011] [Indexed: 11/19/2022] Open
Abstract
Mitochondria are indispensable in the life and death of many types of eukaryotic cells. In pancreatic beta cells, mitochondria play an essential role in the secretion of insulin, a hormone that regulates blood glucose levels. Unregulated blood glucose is a hallmark symptom of diabetes. The onset of Type 1 diabetes is preceded by autoimmune-mediated destruction of beta cells. However, the exact role of mitochondria has not been assessed in beta cell death. In this study, we examine the role of mitochondria in both Fas- and proinflammatory cytokine-mediated destruction of the human beta cell line, βLox5. IFNγ primed βLox5 cells for apoptosis by elevating cell surface Fas. Consequently, βLox5 cells were killed by caspase-dependent apoptosis by agonistic activation of Fas, but only after priming with IFNγ. This beta cell line undergoes both apoptotic and necrotic cell death after incubation with the combination of the proinflammatory cytokines IFNγ and TNFα. Additionally, both caspase-dependent and -independent mechanisms that require proper mitochondrial function are involved. Mitochondrial contributions to βLox5 cell death were analyzed using mitochondrial DNA (mtDNA) depleted βLox5 cells, or βLox5 ρ0 cells. βLox5 ρ0 cells are not sensitive to IFNγ and TNFα killing, indicating a direct role for the mitochondria in cytokine-induced cell death of the parental cell line. However, βLox5 ρ0 cells are susceptible to Fas killing, implicating caspase-dependent extrinsic apoptotic death is the mechanism by which these human beta cells die after Fas ligation. These data support the hypothesis that immune mediators kill βLox5 cells by both mitochondrial-dependent intrinsic and caspase-dependent extrinsic pathways.
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Affiliation(s)
- Yaíma L. Lightfoot
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, United States of America
| | - Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, United States of America
| | - Clayton E. Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, United States of America
- * E-mail:
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Heiman-Patterson TD, Sher RB, Blankenhorn EA, Alexander G, Deitch JS, Kunst CB, Maragakis N, Cox G. Effect of genetic background on phenotype variability in transgenic mouse models of amyotrophic lateral sclerosis: a window of opportunity in the search for genetic modifiers. ACTA ACUST UNITED AC 2011; 12:79-86. [PMID: 21241159 DOI: 10.3109/17482968.2010.550626] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Transgenic (Tg) mouse models of FALS containing mutant human SOD1 genes (G37R, G85R, D90A, or G93A missense mutations or truncated SOD1) exhibit progressive neurodegeneration of the motor system that bears a striking resemblance to ALS, both clinically and pathologically. The most utilized and best characterized Tg mice are the G93A mutant hSOD1 (Tg(hSOD1-G93A)1GUR mice), abbreviated G93A. In this review we highlight what is known about background-dependent differences in disease phenotype in transgenic mice that carry mutated human or mouse SOD1. Expression of G93A-hSOD1Tg in congenic lines with ALR, NOD.Rag1KO, SJL or C3H backgrounds show a more severe phenotype than in the mixed (B6xSJL) hSOD1Tg mice, whereas a milder phenotype is observed in B6, B10, BALB/c and DBA inbred lines. We hypothesize that the background differences are due to disease-modifying genes. Identification of modifier genes can highlight intracellular pathways already suspected to be involved in motor neuron degeneration; it may also point to new pathways and processes that have not yet been considered. Most importantly, identified modifier genes provide new targets for the development of therapies.
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Hou R, Zhang J, Yin T, Cao H, Zhang N, Li X, Wang L, Xing Y, Li D, Ji Q. Upregulation of PTEN by peroxynitrite contributes to cytokine-induced apoptosis in pancreatic beta-cells. Apoptosis 2010; 15:877-86. [PMID: 20464496 DOI: 10.1007/s10495-010-0510-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Phosphatase and tensin homolog (PTEN), a tumor suppressor gene, by negatively regulating the PI3K-Akt signaling pathway, participates in multiple biological processes such as cell proliferation, apoptosis, differentiation, and migration. Recent studies show that selective deletion of PTEN in pancreatic beta-cells leads to resistance to streptozotocin (STZ)-induced diabetes, but the mechanism is unclear. One major mechanism underlying STZ toxicity is cytokine-mediated beta-cell destruction in which oxidative stress plays a key role. The present study investigated the role of PTEN in cytokine-induced beta-cell apoptosis, and further explored whether oxidative stress, particularly peroxynitrite formation, could regulate PTEN-Akt pathway. Incubation of betaTC-6 cells with cytokine mixture (IL-1beta, TNF-alpha, and IFN-gamma) or exogenous peroxynitrite significantly increased apoptotic cell percentage, elevated PTEN and p-PTEN levels, and inhibited Akt activation. Transfection with PTEN-specific siRNA protected betaTC-6 cells from cytokine or peroxynitrite-mediated cell apoptosis and partially reversed Akt inhibition. Furthermore, nitrotyrosine formation, an indicator of peroxynitrite production, was significantly elevated after cytokine treatment. Preventing peroxynitrite formation by administrating NAC/L: -NMMA, or scavenging peroxynitrite directly by UA, attenuated cytokine-induced PTEN upregulation, Akt inhibition, and beta-cell apoptosis. These findings suggest that peroxynitrite-mediated PTEN upregulation plays an important role in cytokine-induced pancreatic beta-cell apoptosis.
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Affiliation(s)
- Rongrong Hou
- Department of Endocrinology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
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Xiang FL, Lu X, Strutt B, Hill DJ, Feng Q. NOX2 deficiency protects against streptozotocin-induced beta-cell destruction and development of diabetes in mice. Diabetes 2010; 59:2603-11. [PMID: 20627937 PMCID: PMC3279537 DOI: 10.2337/db09-1562] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE The role of NOX2-containing NADPH oxidase in the development of diabetes is not fully understood. We hypothesized that NOX2 deficiency decreases reactive oxygen species (ROS) production and immune response and protects against streptozotocin (STZ)-induced β-cell destruction and development of diabetes in mice. RESEARCH DESIGN AND METHODS Five groups of mice--wild-type (WT), NOX2(-/-), WT treated with apocynin, and WT adoptively transferred with NOX2(-/-) or WT splenocytes--were treated with multiple-low-dose STZ. Blood glucose and insulin levels were monitored, and an intraperitoneal glucose tolerance test was performed. Isolated WT and NOX2(-/-) pancreatic islets were treated with cytokines for 48 h. RESULTS Significantly lower blood glucose levels, higher insulin levels, and better glucose tolerance was observed in NOX2(-/-) mice and in WT mice adoptively transferred with NOX2(-/-) splenocytes compared with the respective control groups after STZ treatment. Compared with WT, β-cell apoptosis, as determined by TUNEL staining, and insulitis were significantly decreased, whereas β-cell mass was significantly increased in NOX2(-/-) mice. In response to cytokine stimulation, ROS production was significantly decreased, and insulin secretion was preserved in NOX2(-/-) compared with WT islets. Furthermore, proinflammatory cytokine release induced by concanavalin A was significantly decreased in NOX2(-/-) compared with WT splenocytes. CONCLUSIONS NOX2 deficiency decreases β-cell destruction and preserves islet function in STZ-induced diabetes by reducing ROS production, immune response, and β-cell apoptosis.
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Affiliation(s)
- Fu-Li Xiang
- From the Departments of Medicine, Physiology, and Pharmacology, University of Western Ontario, Lawson Health Research Institute, London, Ontario, Canada
| | - Xiangru Lu
- From the Departments of Medicine, Physiology, and Pharmacology, University of Western Ontario, Lawson Health Research Institute, London, Ontario, Canada
| | - Brenda Strutt
- From the Departments of Medicine, Physiology, and Pharmacology, University of Western Ontario, Lawson Health Research Institute, London, Ontario, Canada
| | - David J. Hill
- From the Departments of Medicine, Physiology, and Pharmacology, University of Western Ontario, Lawson Health Research Institute, London, Ontario, Canada
| | - Qingping Feng
- From the Departments of Medicine, Physiology, and Pharmacology, University of Western Ontario, Lawson Health Research Institute, London, Ontario, Canada
- Corresponding author: Qingping Feng,
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Tse HM, Thayer TC, Steele C, Cuda CM, Morel L, Piganelli JD, Mathews CE. NADPH oxidase deficiency regulates Th lineage commitment and modulates autoimmunity. THE JOURNAL OF IMMUNOLOGY 2010; 185:5247-58. [PMID: 20881184 DOI: 10.4049/jimmunol.1001472] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Reactive oxygen species are used by the immune system to eliminate infections; however, they may also serve as signaling intermediates to coordinate the efforts of the innate and adaptive immune systems. In this study, we show that by eliminating macrophage and T cell superoxide production through the NADPH oxidase (NOX), T cell polarization was altered. After stimulation with immobilized anti-CD3 and anti-CD28 or priming recall, T cells from NOX-deficient mice exhibited a skewed Th17 phenotype, whereas NOX-intact cells produced cytokines indicative of a Th1 response. These findings were corroborated in vivo by studying two different autoimmune diseases mediated by Th17 or Th1 pathogenic T cell responses. NOX-deficient NOD mice were Th17 prone with a concomitant susceptibility to experimental allergic encephalomyelitis and significant protection against type 1 diabetes. These data validate the role of superoxide in shaping Th responses and as a signaling intermediate to modulate Th17 and Th1 T cell responses.
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Affiliation(s)
- Hubert M Tse
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
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Thayer TC, Wilson SB, Mathews CE. Use of nonobese diabetic mice to understand human type 1 diabetes. Endocrinol Metab Clin North Am 2010; 39:541-61. [PMID: 20723819 PMCID: PMC2925291 DOI: 10.1016/j.ecl.2010.05.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In 1922, Leonard Thompson received the first injections of insulin prepared from the pancreas of canine test subjects. From pancreatectomized dogs to the more recent development of animal models that spontaneously develop autoimmune syndromes, animal models have played a meaningful role in furthering diabetes research. Of these animals, the nonobese diabetic (NOD) mouse is the most widely used for research in type 1 diabetes (T1D) because the NOD shares several genetic and immunologic traits with the human form of the disease. In this article, the authors discuss the similarities and differences in NOD and human T1D and the potential role of NOD mice in future preclinical studies, aiming to provide a better understanding of the genetic and immune defects that lead to T1D.
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Affiliation(s)
- Terri C Thayer
- Department of Pathology, Immunology, and Laboratory Medicine, The University of Florida College of Medicine, Gainesville, FL 32610, USA
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Polewicz D, Cadete VJJ, Doroszko A, Hunter BE, Sawicka J, Szczesna-Cordary D, Light PE, Sawicki G. Ischemia induced peroxynitrite dependent modifications of cardiomyocyte MLC1 increases its degradation by MMP-2 leading to contractile dysfunction. J Cell Mol Med 2010; 15:1136-47. [PMID: 20518849 PMCID: PMC2953580 DOI: 10.1111/j.1582-4934.2010.01094.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Damage to cardiac contractile proteins during ischemia followed by reperfusion is mediated by reactive oxygen species such as peroxynitrite (ONOO−), resulting in impairment of cardiac systolic function. However, the pathophysiology of systolic dysfunction during ischemia only, before reperfusion, remains unclear. We suggest that increased ONOO− generation during ischemia leads to nitration/nitrosylation of myosin light chain 1 (MLC1) and its increased degradation by matrix metalloproteinase-2 (MMP-2), which leads to impairment of cardiomyocyte contractility. We also postulate that inhibition of ONOO− action by use of a ONOO− scavenger results in improved recovery from ischemic injury. Isolated rat cardiomyocytes were subjected to 15 and 60 min. of simulated ischemia. Intact MLC1 levels, measured by 2D gel electrophoresis and immunoblot, were shown to decrease with increasing duration of ischemia, which correlated with increasing levels of nitrotyrosine and nitrite/nitrate. In vitro degradation of human recombinant MLC1 by MMP-2 increased after ONOO− exposure of MLC1 in a concentration-dependent manner. Mass spectrometry analysis of ischemic rat cardiomyocyte MLC1 showed nitration of tyrosines 78 and 190, as well as of corresponding tyrosines 73 and 185 within recombinant human cardiac MLC1 treated with ONOO−. Recombinant human cardiac MLC1 was additionally nitrosylated at cysteine 67 and 76 corresponding to cysteine 81 of rat MLC1. Here we show that increased ONOO− production during ischemia induces MLC1 nitration/nitrosylation leading to its increased degradation by MMP-2. Inhibition of MLC1 nitration/nitrosylation during ischemia by the ONOO− scavenger FeTPPS (5,10,15,20-tetrakis-[4-sulfonatophenyl]-porphyrinato-iron[III]), or inhition of MMP-2 activity with phenanthroline, provides an effective protection of cardiomyocyte contractility.
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Affiliation(s)
- Dorota Polewicz
- Department of Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Takahashi T, Matsumoto S, Matsushita M, Kamachi H, Tsuruga Y, Kasai H, Watanabe M, Ozaki M, Furukawa H, Umezawa K, Todo S. Donor pretreatment with DHMEQ improves islet transplantation. J Surg Res 2010; 163:e23-34. [PMID: 20638688 DOI: 10.1016/j.jss.2010.04.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2009] [Revised: 04/07/2010] [Accepted: 04/23/2010] [Indexed: 01/12/2023]
Abstract
BACKGROUND Currently, pancreatic islet transplantation to achieve normoglycemia in insulin-dependent diabetes mellitus (IDDM) requires two or more donors. This may be due to the inability to transplant functionally preserved and viable islets after isolation. Islets have already been subjected to various harmful stresses during the isolation process leading to apoptosis. One of the intracellular signaling pathways, the transcription factor nuclear factor-kappaB (NF-kappaB)-related pathway, is relevant to the mechanism of beta-cell apoptosis in isolated islets. We attempted to prevent islet apoptosis during isolation by a novel NF-kappaB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ). MATERIALS AND METHODS DHMEQ was injected intraperitoneally into donor mice 2 h prior to isolation. NF-kappaB activation, the functioning of isolated islets, apoptosis after isolation, and cytokine- and apoptosis-related genes were analyzed. After 160 equivalents of islets were transplanted into diabetic mice, graft survival and function were evaluated. RESULTS Intra-islet NF-kappaB was activated immediately after isolation, and DHMEQ inhibited NF-kappaB activation without deterioration of islet function. DHMEQ significantly prevented apoptosis by inhibiting caspase 3/7 activities and down-regulated Bax, a pro-apoptotic gene. Donor pretreatment with DHMEQ significantly improved engraftment in syngeneic islet transplantation in mice, thus preserving insulin contents in the graft liver, as assessed by functional and histologic analyses. CONCLUSIONS DHMEQ is a promising agent in islet transplantation because it protects islets from apoptosis during isolation stress. Donor pretreatment with DHMEQ can significantly affect the success of islet engraftment.
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Affiliation(s)
- Tohru Takahashi
- Department of General Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
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Chromogranin A is an autoantigen in type 1 diabetes. Nat Immunol 2010; 11:225-31. [PMID: 20139986 DOI: 10.1038/ni.1844] [Citation(s) in RCA: 275] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Accepted: 01/15/2010] [Indexed: 12/16/2022]
Abstract
Autoreactive CD4(+) T cells are involved in the pathogenesis of many autoimmune diseases, but the antigens that stimulate their responses have been difficult to identify and in most cases are not well defined. In the nonobese diabetic (NOD) mouse model of type 1 diabetes, we have identified the peptide WE14 from chromogranin A (ChgA) as the antigen for highly diabetogenic CD4(+) T cell clones. Peptide truncation and extension analysis shows that WE14 bound to the NOD mouse major histocompatibility complex class II molecule I-A(g7) in an atypical manner, occupying only the carboxy-terminal half of the I-A(g7) peptide-binding groove. This finding extends the list of T cell antigens in type 1 diabetes and supports the idea that autoreactive T cells respond to unusually presented self peptides.
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McCarty MF, Barroso-Aranda J, Contreras F. High-dose folate and dietary purines promote scavenging of peroxynitrite-derived radicals – Clinical potential in inflammatory disorders. Med Hypotheses 2009; 73:824-34. [DOI: 10.1016/j.mehy.2008.09.058] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Revised: 09/12/2008] [Accepted: 09/18/2008] [Indexed: 01/02/2023]
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Hughes KJ, Chambers KT, Meares GP, Corbett JA. Nitric oxides mediates a shift from early necrosis to late apoptosis in cytokine-treated β-cells that is associated with irreversible DNA damage. Am J Physiol Endocrinol Metab 2009; 297:E1187-96. [PMID: 19738038 PMCID: PMC2781357 DOI: 10.1152/ajpendo.00214.2009] [Citation(s) in RCA: 38] [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] [Indexed: 01/28/2023]
Abstract
For many cell types, including pancreatic β-cells, nitric oxide is a mediator of cell death; however, it is paradoxical that for a given cell type nitric oxide can induce both necrosis and apoptosis. This report tests the hypothesis that cell death mediated by nitric oxide shifts from an early necrotic to a late apoptotic event. Central to this transition is the ability of β-cells to respond and repair nitric oxide-mediated damage. β-Cells have the ability to repair DNA that is damaged following 24-h incubation with IL-1; however, cytokine-induced DNA damage becomes irreversible following 36-h incubation. This irreversible DNA damage following 36-h incubation with IL-1 correlates with the activation of caspase-3 (cleavage and activity). The increase in caspase activity correlates with reductions in endogenous nitric oxide production, as nitric oxide is an inhibitor of caspase activity. In contrast, caspase cleavage or activation is not observed under conditions in which β-cells are capable of repairing damaged DNA (24-h incubation with cytokines). These findings provide evidence that β-cell death in response to cytokines shifts from an early necrotic process to apoptosis and that this shift is associated with irreversible DNA damage and caspase-3 activation.
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Affiliation(s)
- Katherine J Hughes
- The Comprehensive Diabetes Center, Univ. of Alabama Birmingham, 12th Floor Shelby, 1530 3rd Ave. South, Birmingham, AL 35294, USA
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Chen J, Gusdon AM, Thayer TC, Mathews CE. Role of increased ROS dissipation in prevention of T1D. Ann N Y Acad Sci 2009; 1150:157-66. [PMID: 19120287 DOI: 10.1196/annals.1447.045] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Protection of pancreatic beta cells is an approach to prevent autoimmune type 1 diabetes (T1D) and to protect transplanted islets. Reactive oxygen species (ROS) are important mediators of beta cell death during the development of T1D. We have examined the role of elevated ROS dissipation in the prevention of T1D using the ALR mouse strain. The selection of ALR, for resistance against alloxan-induced free radical-mediated diabetes, led to a strain of mice with an elevated systemic as well as pancreatic ROS dissipation. Independent genetic mapping studies have identified ALR-derived diabetes protective loci. Conplastic and congenic mouse as well as cell line studies have confirmed the genetic mapping and demonstrated that the elevated ROS dissipation protects ALR beta cells from autoimmune destruction. Our data support the hypothesis that elevated ROS dissipation protects beta cells against autoimmune destruction and prevents T1D development.
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Affiliation(s)
- Jing Chen
- Department of Pathology, University of Florida College of Medicine, Gainesville, Florida 32610-0275, USA
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Ueno A, Wang J, Cheng L, Im JS, Shi Y, Porcelli SA, Yang Y. Enhanced Early Expansion and Maturation of Semi-Invariant NK T Cells Inhibited Autoimmune Pathogenesis in Congenic Nonobese Diabetic Mice. THE JOURNAL OF IMMUNOLOGY 2008; 181:6789-96. [DOI: 10.4049/jimmunol.181.10.6789] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Chen J, Lu Y, Lee CH, Li R, Leiter EH, Mathews CE. Commonalities of genetic resistance to spontaneous autoimmune and free radical--mediated diabetes. Free Radic Biol Med 2008; 45:1263-70. [PMID: 18718526 PMCID: PMC2872108 DOI: 10.1016/j.freeradbiomed.2008.07.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 07/17/2008] [Accepted: 07/24/2008] [Indexed: 10/21/2022]
Abstract
ALR/Lt, a NOD-related mouse strain, was selected for resistance to alloxan free radical-mediated diabetes (ALD). Despite extensive genomic identity with NOD (>70%), ALR mice display strong resistance to autoimmune type 1 diabetes (T1D) due to both an unusual elevation in systemic antioxidant defenses and a reduction in cellular ROS production that extends to the beta cell level. Reciprocal backcross to NOD previously linked the ALR-derived T1D resistance to Chr. 3, 8, and 17 as well as to the ALR mt-Nd2(a) allele encoded by the mitochondrial genome (mtDNA). To determine whether any of the ALR-derived loci protecting against T1D also protected against ALD, 296 six-week-old F2 mice from reciprocal outcrosses were alloxan-treated and assessed for diabetes onset, and a genome-wide scan (GWS) was conducted. GWS linked mt-Nd2 as well as three nuclear loci with alloxan-induced diabetes. A dominant ALR-derived ALD resistance locus on Chr. 8 colocalized with the ALR-derived T1D resistance locus identified in the previous backcross analysis. In contrast, whereas ALR contributed a novel T1D resistance locus on Chr. 3 marked by Susp, a more proximal ALR-derived region marked by Il-2 contributed ALD susceptibility, not resistance. In addition, a locus was mapped on Chr. 2, where heterozygosity provided heightened susceptibility. Tests for alloxan sensitivity in ALR conplastic mice encoding the NOD mt-Nd2(c) allele and NOD mice congenic for the protective Chr. 8 locus supported our mapping results. Alloxan sensitivity was increased in ALR.mt(NOD) mice, whereas it was decreased by congenic introduction of ALR genome on Chr. 8 into NOD. These data demonstrate both similarities and differences in the genetic control of T1D versus ROS-induced diabetes.
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Affiliation(s)
- Jing Chen
- Department of Pediatrics, The University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- The Jackson Laboratory, Bar Harbor, ME, 04609–1500, USA
| | - Ying Lu
- Department of Pediatrics, The University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Chul-Ho Lee
- The Jackson Laboratory, Bar Harbor, ME, 04609–1500, USA
| | - Renhua Li
- The Jackson Laboratory, Bar Harbor, ME, 04609–1500, USA
| | | | - Clayton E. Mathews
- Department of Pediatrics, The University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- To whom correspondence should be sent: Clayton E. Mathews, 1600 SW Archer Road, P.O. Box 100275, Gainesville, FL, 32610–0275, Phone 352–392–9803, Fax 352–392–5393,
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Kanitkar M, Gokhale K, Galande S, Bhonde RR. Novel role of curcumin in the prevention of cytokine-induced islet death in vitro and diabetogenesis in vivo. Br J Pharmacol 2008; 155:702-13. [PMID: 18695642 DOI: 10.1038/bjp.2008.311] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND AND PURPOSE Oxidative stress caused by cytokine exposure is a major cause of pancreatic islet death in vitro and of diabetogenesis. Antioxidant compounds may prevent cytokine-induced damage to islet cells. Hence, we studied the potential of curcumin, an antioxidant and anti-inflammatory compound, in vitro to protect islets against pro-inflammatory cytokines and in vivo to prevent the progression of diabetes induced by multiple low doses of streptozotocin (MLD-STZ). EXPERIMENTAL APPROACH Pancreatic islets from C57/BL6J mice were pretreated with curcumin (10 microM) and then exposed to a combination of cytokines. Islet viability, reactive oxygen species (ROS), NO, inducible NO synthase and NF-kappaB translocation were studied. Curcumin pretreated (7.5 mg kg(-1) day(-1)) C57/BL6J mice were given MLD-STZ (40 mg kg(-1)), and various parameters of diabetes induction and progression were monitored. KEY RESULTS Curcumin protected islets from cytokine-induced islet death in vitro by scavenging ROS and normalized cytokine-induced NF-kappaB translocation by inhibiting phosphorylation of inhibitor of kappa B alpha (IkappaBalpha). In vivo, curcumin also prevented MLD-STZ, as revealed by sustained normoglycaemia, normal glucose clearance and maintained pancreatic GLUT2 levels. Pro-inflammatory cytokine concentrations in the serum and pancreas were raised in STZ-treated animals, but not in animals pretreated with curcumin before STZ. CONCLUSIONS AND IMPLICATIONS Here, we have demonstrated for the first time that curcumin in vitro protects pancreatic islets against cytokine-induced death and dysfunction and in vivo prevents STZ-induced diabetes.
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Affiliation(s)
- M Kanitkar
- Tissue Engineering and Banking Laboratory, National Centre for Cell Science, Pune, Maharashtra, India
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da Silva Krause M, de Bittencourt PIH. Type 1 diabetes: can exercise impair the autoimmune event? TheL-arginine/glutamine coupling hypothesis. Cell Biochem Funct 2008; 26:406-33. [DOI: 10.1002/cbf.1470] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Chambers KT, Unverferth JA, Weber SM, Wek RC, Urano F, Corbett JA. The role of nitric oxide and the unfolded protein response in cytokine-induced beta-cell death. Diabetes 2008; 57:124-32. [PMID: 17928398 DOI: 10.2337/db07-0944] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE The unfolded protein response (UPR) is a conserved cellular response designed to alleviate damage and promote survival of cells experiencing stress; however, prolonged UPR activation can result in apoptotic cell death. The UPR, activated by cytokine-induced nitric oxide (NO) production, has been proposed to mediate beta-cell death in response to cytokines. In this study, the role of UPR activation in cytokine-induced beta-cell death was examined. RESEARCH DESIGN AND METHODS The effects of cytokine treatment of rat and human islets and RINm5F cells on UPR activation, NO production, and cell viability were examined using molecular and biochemical methodologies. RESULTS UPR activation correlates with beta-cell death in interleukin (IL)-1-treated rat islets. NO mediates both cytokine-induced UPR activation and beta-cell death as NO synthase inhibitors attenuate each of these IL-1-stimulated events. Importantly, cytokines and tunicamycin, a classical UPR activator, induce beta-cell death by different mechanisms. Cell death in response to the classical UPR activator is associated with a 2.5-fold increase in caspase-3 activity, while IL-1 fails to stimulate caspase-3 activity. In addition, cell death is enhanced by approximately 35% in tunicamycin-treated cells expressing an S51A eIF2 alpha mutant that cannot be phosphorylated or in cells lacking PERK (protein kinase regulated by RNA/endoplasmic reticulum-like kinase). In contrast, neither the absence of PERK nor the expression of the S51A eIF2 alpha mutant affects the levels of cytokine-induced death. CONCLUSIONS While cytokine-induced beta-cell death temporally correlates with UPR activation, the lack of caspase activity and the ability of NO to attenuate caspase activity suggest that prolonged UPR activation does not mediate cytokine-induced beta-cell death.
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Affiliation(s)
- Kari T Chambers
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, Saint Louis, Missouri, USA
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Abstract
Inbred mouse strains provide genetic diversity comparable to that of the human population. Like humans, mice have a wide range of diabetes-related phenotypes. The inbred mouse strains differ in the response of their critical physiological functions, such as insulin sensitivity, insulin secretion, beta-cell proliferation and survival, and fuel partitioning, to diet and obesity. Most of the critical genes underlying these differences have not been identified, although many loci have been mapped. The dramatic improvements in genomic and bioinformatics resources are accelerating the pace of gene discovery. This review describes how mouse genetics can be used to discover diabetes-related genes, summarizes how the mouse strains differ in their diabetes-related phenotypes, and describes several examples of how loci identified in the mouse may directly relate to human diabetes.
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Affiliation(s)
- Susanne M Clee
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, Wisconsin 53706-1544, USA
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Gusdon AM, Votyakova TV, Reynolds IJ, Mathews CE. Nuclear and Mitochondrial Interaction Involving mt-Nd2 Leads to Increased Mitochondrial Reactive Oxygen Species Production. J Biol Chem 2007; 282:5171-9. [PMID: 17189252 DOI: 10.1074/jbc.m609367200] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
NADH dehydrogenase subunit 2, encoded by the mtDNA, has been associated with resistance to autoimmune type I diabetes (T1D) in a case control study. Recently, we confirmed a role for the mouse ortholog of the protective allele (mt-Nd2(a)) in resistance to T1D using genetic analysis of outcrosses between T1D-resistant ALR and T1D-susceptible NOD mice. We sought to determine the mechanism of disease protection by elucidating whether mt-Nd2(a) affects basal mitochondrial function or mitochondrial function in the presence of oxidative stress. Two lines of reciprocal conplastic mouse strains were generated: one with ALR nuclear DNA and NOD mtDNA (ALR.mt(NOD)) and the reciprocal with NOD nuclear DNA and ALR mtDNA (NOD.mt(ALR)). Basal mitochondrial respiration, transmembrane potential, and electron transport system enzymatic activities showed no difference among the strains. However, ALR.mt(NOD) mitochondria supported by either complex I or complex II substrates produced significantly more reactive oxygen species when compared with both parental strains, NOD.mt(ALR) or C57BL/6 controls. Nitric oxide inhibited respiration to a similar extent for mitochondria from the five strains due to competitive antagonism with molecular oxygen at complex IV. Superoxide and hydrogen peroxide generated by xanthine oxidase did not significantly decrease complex I function. The protein nitrating agents peroxynitrite or nitrogen dioxide radicals significantly decreased complex I function but with no significant difference among the five strains. In summary, mt-Nd2(a) does not confer elevated resistance to oxidative stress; however, it plays a critical role in the control of the mitochondrial reactive oxygen species production.
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Affiliation(s)
- Aaron M Gusdon
- Department of Pediatrics, the University of Pittsburgh School of Medicine and The Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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Armann B, Hanson MS, Hatch E, Steffen A, Fernandez LA. Quantification of basal and stimulated ROS levels as predictors of islet potency and function. Am J Transplant 2007; 7:38-47. [PMID: 17227556 PMCID: PMC2752033 DOI: 10.1111/j.1600-6143.2006.01577.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We have developed a luminol-based assay using intact islets, which allows for quantification of reactive oxygen species (ROS). In addition, an index capable of characterizing metabolic and mitochondrial integrity prior to transplantation was created based on the capacity of islets to respond to high glucose and rotenone (mitochondrial respiratory chain complex I inhibitor) by production of ROS. To validate this assay, lipid peroxidation and antioxidative defense capacity were evaluated by detection of malondialdehyde (MDA) levels and glutathione peroxidase activity (GPx), respectively. Also, flow cytometric analyses of ROS (dihydroethidine), apoptosis (Annexin V, active caspases), necrosis (Topro3), and mitochondrial membrane potential (JC-1) were done in parallel to correlate with changes in luminol-measured ROS. ATP/ADP ratios were quantified by HPLC and the predictive value of ROS measurement on islet functional potency was correlated with capacity to reverse diabetes in a streptozotocin-induced diabetic NOD.scid mouse model as well as in human transplant recipients. Our data demonstrate that levels of ROS in islets correlate with the percentage of apoptotic cells and their functional potency in vivo. The ROS indices following glucose and rotenone exposure are indicative of metabolic potency and mitochondrial integrity and can be used as surrogate markers to evaluate the quality of islets prior to transplantation.
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Affiliation(s)
- B. Armann
- University of Wisconsin-Madison, Department of Surgery, UW Hospital & Clinics, H5/301, 600 Highland Avenue, Madison, WI, USA
- University of Leipzig, Germany, Department of Surgery, Universitaetsklinikum Leipzig, AoeR, Liebigstrasse 21a, 04305 Leipzig, Germany
| | - M. S. Hanson
- University of Wisconsin-Madison, Department of Surgery, UW Hospital & Clinics, H5/301, 600 Highland Avenue, Madison, WI, USA
| | - E. Hatch
- University of Wisconsin-Madison, Department of Surgery, UW Hospital & Clinics, H5/301, 600 Highland Avenue, Madison, WI, USA
| | - A. Steffen
- University of Wisconsin-Madison, Department of Surgery, UW Hospital & Clinics, H5/301, 600 Highland Avenue, Madison, WI, USA
- University of Leipzig, Germany, Department of Surgery, Universitaetsklinikum Leipzig, AoeR, Liebigstrasse 21a, 04305 Leipzig, Germany
| | - L. A. Fernandez
- University of Wisconsin-Madison, Department of Surgery, UW Hospital & Clinics, H5/301, 600 Highland Avenue, Madison, WI, USA
- Corresponding author: L. A. Fernandez,
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Leiter EH, Lee CH. Mouse models and the genetics of diabetes: is there evidence for genetic overlap between type 1 and type 2 diabetes? Diabetes 2005; 54 Suppl 2:S151-8. [PMID: 16306333 DOI: 10.2337/diabetes.54.suppl_2.s151] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In humans, both type 1 and type 2 diabetes exemplify genetically heterogeneous complex diseases in which epigenetic factors contribute to underlying genetic susceptibility. Extended human pedigrees often show inheritance of both diabetes types. A common pathophysiological denominator in both disease forms is pancreatic beta-cell exposure to proinflammatory cytokines. Hence, it is intuitive that systemically expressed genes regulating beta-cell ability to withstand chronic diabetogenic stress may represent a component of shared susceptibility to both major disease forms. In this review, the authors assemble evidence from genetic experiments using animal models developing clearly distinct diabetes syndromes to inquire whether some degree of overlap in genes contributing susceptibility can be demonstrated. The conclusion is that although overlap exists in the pathophysiological insults leading to beta-cell destruction in the currently studied rodent models, the genetic bases seem quite distinct.
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Affiliation(s)
- Edward H Leiter
- The Jackson Laboratory, 600 Main St., Bar Harbor, Maine 04609, USA.
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