The regulation of oxidative metabolism by nitric oxide protects β-cells from DNA damage-induced cell death

2018 ◽  
Vol 128 ◽  
pp. S96
Author(s):  
Chay Teng Yeo ◽  
Bryndon Oleson ◽  
Katarzyna Broniowska ◽  
Aaron Naatz ◽  
Jamie Schnuck ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Dna Damage ◽  
Cell Death ◽  
Oxidative Metabolism ◽  
Β Cells

scholarly journals The Role of Metabolic Flexibility in the Regulation of the DNA Damage Response by Nitric Oxide

2019 ◽  
Vol 39 (18) ◽  
Author(s):  
Bryndon J. Oleson ◽  
Katarzyna A. Broniowska ◽  
Chay Teng Yeo ◽  
Michael Flancher ◽  
Aaron Naatz ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Dna Damage ◽  
Dna Damage Response ◽  
Oxidative Metabolism ◽  
Protective Mechanism ◽  
Metabolic Flexibility ◽  
Β Cells ◽  
Β Cell ◽  
Damage Response ◽  
Mitochondrial Toxins

ABSTRACTIn this report, we show that nitric oxide suppresses DNA damage response (DDR) signaling in the pancreatic β-cell line INS 832/13 and rat islets by inhibiting intermediary metabolism. Nitric oxide is known to inhibit complex IV of the electron transport chain and aconitase of the Krebs cycle. Non-β cells compensate by increasing glycolytic metabolism to maintain ATP levels; however, β cells lack this metabolic flexibility, resulting in a nitric oxide-dependent decrease in ATP and NAD+. Like nitric oxide, mitochondrial toxins inhibit DDR signaling in β cells by a mechanism that is associated with a decrease in ATP. Non-β cells compensate for the effects of mitochondrial toxins with an adaptive shift to glycolytic ATP generation that allows for DDR signaling. Forcing non-β cells to derive ATP via mitochondrial respiration (replacing glucose with galactose in the medium) and glucose deprivation sensitizes these cells to nitric oxide-mediated inhibition of DDR signaling. These findings indicate that metabolic flexibility is necessary to maintain DDR signaling under conditions in which mitochondrial oxidative metabolism is inhibited and support the inhibition of oxidative metabolism (decreased ATP) as one protective mechanism by which nitric oxide attenuates DDR-dependent β-cell apoptosis.

scholarly journals Differential responses of pancreatic β-cells to ROS and RNS

2013 ◽  
Vol 304 (6) ◽  
pp. E614-E622 ◽  
Author(s):  
Gordon P. Meares ◽  
Dominique Fontanilla ◽  
Katarzyna A. Broniowska ◽  
Teresa Andreone ◽  
Jack R. Lancaster ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Dna Damage ◽  
Cell Death ◽  
Cell Viability ◽  
Cell Fate ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Unfolded Protein ◽  
Heat Shock Responses ◽  
Reduce Cell Viability

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) direct the activation of distinct signaling pathways that determine cell fate. In this study, the pathways activated and the mechanisms by which ROS and RNS control the viability of pancreatic β-cells were examined. Although both nitric oxide and hydrogen peroxide (H2O2) induce DNA damage, reduce cell viability, and activate AMPK, the mechanisms of AMPK activation and cell death induction differ between each reactive species. Nitric oxide activates the unfolded protein and heat shock responses and MAPK kinase signaling, whereas H2O2 stimulates p53 stabilization and poly(ADP-ribose) polymerase (PARP) activation but fails to induce the unfolded protein or heat shock responses or MAPK activation. The control of cell fate decisions is selective for the form of stress. H2O2-mediated reduction in β-cell viability is controlled by PARP, whereas cell death in response to nitric oxide is PARP independent but associated with the nuclear localization of GAPDH. These findings show that both ROS and RNS activate AMPK, induce DNA damage, and reduce cell viability; however, the pathways controlling the responses of β-cells are selective for the type of reactive species.

scholarly journals Nitric oxides mediates a shift from early necrosis to late apoptosis in cytokine-treated β-cells that is associated with irreversible DNA damage

2009 ◽  
Vol 297 (5) ◽  
pp. E1187-E1196 ◽  
Author(s):  
Katherine J. Hughes ◽  
Kari T. Chambers ◽  
Gordon P. Meares ◽  
John A. Corbett
Keyword(s):  
Nitric Oxide ◽  
Dna Damage ◽  
Cell Death ◽  
Caspase 3 ◽  
Cell Types ◽  
Caspase Activity ◽  
Nitric Oxides ◽  
Β Cells ◽  
Caspase Cleavage ◽  
Endogenous Nitric Oxide

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.

scholarly journals Inhibition of oxidative metabolism by nitric oxide restricts EMCV replication selectively in pancreatic beta-cells

2020 ◽  
Vol 295 (52) ◽  
pp. 18189-18198
Author(s):  
Joshua D. Stafford ◽  
Chay Teng Yeo ◽  
John A. Corbett
Keyword(s):  
Nitric Oxide ◽  
Insulin Secretion ◽  
Oxidative Metabolism ◽  
Mitochondrial Respiration ◽  
Pancreatic Beta Cells ◽  
Encephalomyocarditis Virus ◽  
Β Cells ◽  
Β Cell ◽  
Atp Levels ◽  
Mitochondrial Oxidative Metabolism

Environmental factors, such as viral infection, are proposed to play a role in the initiation of autoimmune diabetes. In response to encephalomyocarditis virus (EMCV) infection, resident islet macrophages release the pro-inflammatory cytokine IL-1β, to levels that are sufficient to stimulate inducible nitric oxide synthase (iNOS) expression and production of micromolar levels of the free radical nitric oxide in neighboring β-cells. We have recently shown that nitric oxide inhibits EMCV replication and EMCV-mediated β-cell lysis and that this protection is associated with an inhibition of mitochondrial oxidative metabolism. Here we show that the protective actions of nitric oxide against EMCV infection are selective for β-cells and associated with the metabolic coupling of glycolysis and mitochondrial oxidation that is necessary for insulin secretion. Inhibitors of mitochondrial respiration attenuate EMCV replication in β-cells, and this inhibition is associated with a decrease in ATP levels. In mouse embryonic fibroblasts (MEFs), inhibition of mitochondrial metabolism does not modify EMCV replication or decrease ATP levels. Like most cell types, MEFs have the capacity to uncouple the glycolytic utilization of glucose from mitochondrial respiration, allowing for the maintenance of ATP levels under conditions of impaired mitochondrial respiration. It is only when MEFs are forced to use mitochondrial oxidative metabolism for ATP generation that mitochondrial inhibitors attenuate viral replication. In a β-cell selective manner, these findings indicate that nitric oxide targets the same metabolic pathways necessary for glucose stimulated insulin secretion for protection from viral lysis.

scholarly journals Inhibition of mitochondrial oxidative metabolism attenuates EMCV replication and protects β-cells from virally mediated lysis

2020 ◽  
Vol 295 (49) ◽  
pp. 16655-16664 ◽  
Author(s):  
Joshua D. Stafford ◽  
Zachary R. Shaheen ◽  
Chay Teng Yeo ◽  
John A. Corbett
Keyword(s):  
Nitric Oxide ◽  
Viral Replication ◽  
Viral Infection ◽  
Oxidative Metabolism ◽  
Cell Lysis ◽  
Encephalomyocarditis Virus ◽  
Dependent Manner ◽  
Β Cells ◽  
Β Cell ◽  
Mitochondrial Oxidative Metabolism

Viral infection is one environmental factor that may contribute to the initiation of pancreatic β-cell destruction during the development of autoimmune diabetes. Picornaviruses, such as encephalomyocarditis virus (EMCV), induce a pro-inflammatory response in islets leading to local production of cytokines, such as IL-1, by resident islet leukocytes. Furthermore, IL-1 is known to stimulate β-cell expression of iNOS and production of the free radical nitric oxide. The purpose of this study was to determine whether nitric oxide contributes to the β-cell response to viral infection. We show that nitric oxide protects β-cells against virally mediated lysis by limiting EMCV replication. This protection requires low micromolar, or iNOS-derived, levels of nitric oxide. At these concentrations nitric oxide inhibits the Krebs enzyme aconitase and complex IV of the electron transport chain. Like nitric oxide, pharmacological inhibition of mitochondrial oxidative metabolism attenuates EMCV-mediated β-cell lysis by inhibiting viral replication. These findings provide novel evidence that cytokine signaling in β-cells functions to limit viral replication and subsequent β-cell lysis by attenuating mitochondrial oxidative metabolism in a nitric oxide–dependent manner.

2-Methoxy-6-Acetyl-7-Methyljuglone (MAM) Induces iNOS/NO-mediated DNA Damage Response through Activation of MAPKs Pathways

2018 ◽  
Vol 18 (6) ◽  
pp. 903-913 ◽  
Author(s):  
Yanan Niu ◽  
Renyikun Yuan ◽  
Hongwei Gao ◽  
Jin-Jian Lu ◽  
Qi Kong ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Dna Damage ◽  
Cell Death ◽  
Dna Damage Response ◽  
Cancer Progression ◽  
A549 Cells ◽  
No Production ◽  
Damage Response

Background：There are inconsistent reports about the role of Nitric Oxide (NO) in cancer progression and prevention. Quinones demonstrate significant anti-cancer activities both in vitro and in vivo. Objective： We investigated the effect of 2-methoxy-6-acetyl-7-methyljuglone (MAM), a natural naphthoquinone isolated from Polygonum cuspidatum Sieb. et Zucc, on NO generation and its role in DNA damage in cancer cells. Methods: BEL-7402 and A549 cells were cultured and treated with MAM. The NO generation, DNA damage, and protein expression were determined. Results: MAM induced inducible nitric oxide synthase (iNOS)/NO-mediated DNA damage response through activation of MAPKs pathways. MAM induced DNA damage by activating ATM/Chk2. MAM increased iNOS expression, NO production, and MAPKs (JNK1/2, ERK1/2, and p38MAPK) phosphorylation in concentrationand time- dependent manners. Furthermore, iNOS inhibitor 1400W, iNOS siRNA, and NO scavenger hemoglobin (Hb) could significantly reverse MAM-induced DNA damage, ATM/Chk2 activation, NO production, and cell death. In addition, MAPKs inhibitors (SP600125, U0126, and SB203580) reversed MAM-induced cell death and ATM/Chk2 activation. MAM-induced cell death was partially reversed by 1400W and Hb but enhanced by L-arginine. Conclusion: These results suggested that MAM induced iNOS/NO activation and generation mediated by MAPKs pathways, which resulted in DNA damage.

scholarly journals Nitric Oxide Suppresses β-Cell Apoptosis by Inhibiting the DNA Damage Response

2016 ◽  
Vol 36 (15) ◽  
pp. 2067-2077 ◽  
Author(s):  
Bryndon J. Oleson ◽  
Katarzyna A. Broniowska ◽  
Aaron Naatz ◽  
Neil Hogg ◽  
Vera L. Tarakanova ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Dna Damage ◽  
Cell Survival ◽  
Dna Damage Response ◽  
Cell Apoptosis ◽  
Β Cells ◽  
Β Cell ◽  
Pancreatic Β Cells ◽  
Damage Response ◽  
Induced Apoptosis

Nitric oxide, produced in pancreatic β cells in response to proinflammatory cytokines, plays a dual role in the regulation of β-cell fate. While nitric oxide induces cellular damage and impairs β-cell function, it also promotes β-cell survival through activation of protective pathways that promote β-cell recovery. In this study, we identify a novel mechanism in which nitric oxide prevents β-cell apoptosis by attenuating the DNA damage response (DDR). Nitric oxide suppresses activation of the DDR (as measured by γH2AX formation and the phosphorylation of KAP1 and p53) in response to multiple genotoxic agents, including camptothecin, H2O2, and nitric oxide itself, despite the presence of DNA damage. While camptothecin and H2O2both induce DDR activation, nitric oxide suppresses only camptothecin-induced apoptosis and not H2O2-induced necrosis. The ability of nitric oxide to suppress the DDR appears to be selective for pancreatic β cells, as nitric oxide fails to inhibit DDR signaling in macrophages, hepatocytes, and fibroblasts, three additional cell types examined. While originally described as the damaging agent responsible for cytokine-induced β-cell death, these studies identify a novel role for nitric oxide as a protective molecule that promotes β-cell survival by suppressing DDR signaling and attenuating DNA damage-induced apoptosis.

scholarly journals Mechanisms of cytokine-induced death of cultured bovine luteal cells

Reproduction ◽  
2001 ◽  
pp. 753-760 ◽  
Author(s):  
MG Petroff ◽  
BK Petroff ◽  
JL Pate
Keyword(s):  
Nitric Oxide ◽  
Dna Damage ◽  
Cell Death ◽  
Culture Media ◽  
Luteal Cell ◽  
Tnf Alpha ◽  
Ifn Gamma ◽  
Luteal Cells ◽  
Arachidonate Metabolism

Tumour necrosis factor alpha (TNF-alpha) and gamma-interferon (IFN-gamma) are cytotoxic to bovine luteal cells in vitro and may contribute to cell death during luteolysis in vivo. In this study, the mechanism by which luteal cells are killed by TNF-alpha and IFN-gamma was investigated. Luteal cells were cultured for 7 days in the presence or absence of TNF-alpha and IFN-gamma. Inhibitors of arachidonate metabolism or scavengers of free radicals were included in the culture media. In addition, the effect of IFN-beta on the viability of cytokine-treated luteal cells was tested. Lastly, untreated and cytokine-treated cells were subjected to single cell gel electrophoresis for quantification of DNA fragmentation. Neither indomethacin nor nordihydroguaiaretic acid, which are inhibitors of cyclooxygenase and lipoxygenase, respectively, were able to prevent cytokine-induced cell death. Similarly, both the phospholipase A(2) inhibitor arachidonyltrifluoromethyl ketone and the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine, were largely without effect. In contrast, while vitamin C did not significantly affect viability, superoxide dismutase plus catalase increased viability of cytokine-treated cells (P < 0.05), and IFN-beta prevented cell death (P < 0.05). Finally, while control cells remained free of DNA damage, TNF-alpha plus IFN-gamma induced significant amounts of DNA damage by 48 h after initiation of treatment (P < 0.05). In conclusion, reactive oxygen species, but not arachidonate metabolism or nitric oxide, contribute to cytokine-induced luteal cell death in vitro, and the process of cell death may be via apoptosis. Furthermore, IFN-beta may confer protective effects against cytokine-induced cell death in bovine luteal cells.

Sign in / Sign up

Export Citation Format

Share Document