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Herb M. NADPH Oxidase 3: Beyond the Inner Ear. Antioxidants (Basel) 2024; 13:219. [PMID: 38397817 PMCID: PMC10886416 DOI: 10.3390/antiox13020219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
Reactive oxygen species (ROS) were formerly known as mere byproducts of metabolism with damaging effects on cellular structures. The discovery and description of NADPH oxidases (Nox) as a whole enzyme family that only produce this harmful group of molecules was surprising. After intensive research, seven Nox isoforms were discovered, described and extensively studied. Among them, the NADPH oxidase 3 is the perhaps most underrated Nox isoform, since it was firstly discovered in the inner ear. This stigma of Nox3 as "being only expressed in the inner ear" was also used by me several times. Therefore, the question arose whether this sentence is still valid or even usable. To this end, this review solely focuses on Nox3 and summarizes its discovery, the structural components, the activating and regulating factors, the expression in cells, tissues and organs, as well as the beneficial and detrimental effects of Nox3-mediated ROS production on body functions. Furthermore, the involvement of Nox3-derived ROS in diseases progression and, accordingly, as a potential target for disease treatment, will be discussed.
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Affiliation(s)
- Marc Herb
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine, University Hospital Cologne, University of Cologne, 50935 Cologne, Germany;
- German Centre for Infection Research, Partner Site Bonn-Cologne, 50931 Cologne, Germany
- Cologne Cluster of Excellence on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50931 Cologne, Germany
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Thome T, Kim K, Dong G, Ryan TE. The Role of Mitochondrial and Redox Alterations in the Skeletal Myopathy Associated with Chronic Kidney Disease. Antioxid Redox Signal 2023; 38:318-337. [PMID: 36245209 PMCID: PMC9986033 DOI: 10.1089/ars.2022.0143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 09/28/2022] [Accepted: 10/01/2022] [Indexed: 11/12/2022]
Abstract
Significance: An estimated 700 million people globally suffer from chronic kidney disease (CKD). In addition to increasing cardiovascular disease risk, CKD is a catabolic disease that results in a loss of muscle mass and function, which are strongly associated with mortality and a reduced quality of life. Despite the importance of muscle health and function, there are no treatments available to prevent or attenuate the myopathy associated with CKD. Recent Advances: Recent studies have begun to unravel the changes in mitochondrial and redox homeostasis within skeletal muscle during CKD. Impairments in mitochondrial metabolism, characterized by reduced oxidative phosphorylation, are found in both rodents and patients with CKD. Associated with aberrant mitochondrial function, clinical and preclinical findings have documented signs of oxidative stress, although the molecular source and species are ill-defined. Critical Issues: First, we review the pathobiology of CKD and its associated myopathy, and we review muscle cell bioenergetics and redox biology. Second, we discuss evidence from clinical and preclinical studies that have implicated the involvement of mitochondrial and redox alterations in CKD-associated myopathy and review the underlying mechanisms reported. Third, we discuss gaps in knowledge related to mitochondrial and redox alterations on muscle health and function in CKD. Future Directions: Despite what has been learned, effective treatments to improve muscle health in CKD remain elusive. Further studies are needed to uncover the complex mitochondrial and redox alterations, including post-transcriptional protein alterations, in patients with CKD and how these changes interact with known or unknown catabolic pathways contributing to poor muscle health and function. Antioxid. Redox Signal. 38, 318-337.
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Affiliation(s)
- Trace Thome
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Kyoungrae Kim
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Gengfu Dong
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
- Center for Exercise Science, University of Florida, Gainesville, Florida, USA
- Myology Institute, University of Florida, Gainesville, Florida, USA
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Jardel HV, Engel LS, Lawrence KG, Stewart PA, Stenzel MR, Curry MD, Kwok RK, Sandler DP. The association between oil spill cleanup-related total hydrocarbon exposure and diabetes. ENVIRONMENTAL RESEARCH 2022; 212:113591. [PMID: 35661735 PMCID: PMC9267393 DOI: 10.1016/j.envres.2022.113591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/21/2022] [Accepted: 05/29/2022] [Indexed: 05/23/2023]
Abstract
BACKGROUND Although evidence suggests relationships between some crude oil components and glycemic dysregulation, no studies have examined oil spill-related chemical exposures in relation to type 2 diabetes mellitus (DM) risk. This study examined the relationship between total hydrocarbon (THC) exposure among workers involved in the 2010 Deepwater Horizon (DWH) oil spill and risk of DM up to 6 years afterward. METHODS Participants comprised 2660 oil-spill cleanup or response workers in the prospective GuLF Study who completed a clinical exam and had no self-reported DM diagnosis prior to the spill. Maximum THC exposure was estimated with a job-exposure matrix based on interview data and personal measurements taken during cleanup operations. We defined incident DM by self-reported physician diagnosis of DM, antidiabetic medication use, or a measured hemoglobin A1c value ≥ 6.5%. We used log binomial regression to estimate risk ratios (RRs) for DM across ordinal categories of THC exposure. The fully adjusted model controlled for age, sex, race/ethnicity, education, employment status, and health insurance status. We also stratified on clinical body mass index categories. RESULTS We observed an exposure-response relationship between maximum daily ordinal THC exposure level and incident DM, especially among overweight participants. RRs among overweight participants were 0.99 (95% CI: 0.37, 2.69), 1.46 (95% CI: 0.54, 3.92), and 2.11 (95% CI: 0.78, 5.74) for exposure categories 0.30-0.99 ppm, 1.00-2.99 ppm, and ≥3.00 ppm, respectively (ptrend = 0.03). CONCLUSION We observed suggestively increasing DM risk with increasing THC exposure level among overweight participants, but not among normal weight or obese participants.
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Affiliation(s)
- H V Jardel
- Department of Epidemiology, UNC Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA.
| | - L S Engel
- Department of Epidemiology, UNC Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA; Epidemiology Branch, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC, USA
| | - K G Lawrence
- Epidemiology Branch, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC, USA
| | - P A Stewart
- Stewart Exposure Assessments, LLC North Arlington, Virginia, USA
| | - M R Stenzel
- Exposure Assessment Applications LLC Arlington, Virginia, USA
| | - M D Curry
- Social and Scientific Systems, Inc., a DLH Holding Company Durham, NC, USA
| | - R K Kwok
- Epidemiology Branch, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC, USA; Office of the Director, National Institute of Environmental Health Sciences, NIH, DHHS, Bethesda, MD, USA
| | - D P Sandler
- Epidemiology Branch, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC, USA
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Colomeu TC, de Figueiredo D, de Matos da Silva P, Fernandes LGR, Zollner RDL. Antiproliferative and Pro-Oxidant Effect of Polyphenols in Aqueous Leaf Extract of Passiflora alata Curtis on Activated T Lymphocytes from Non-Obese Diabetic (NOD SHILT/J) Mice. Antioxidants (Basel) 2022; 11:antiox11081503. [PMID: 36009222 PMCID: PMC9405454 DOI: 10.3390/antiox11081503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 07/18/2022] [Accepted: 07/22/2022] [Indexed: 12/10/2022] Open
Abstract
The antioxidant, anti-inflammatory and antiproliferative properties of Passiflora alata Curtis are due to the presence of polyphenols in its composition. Our previous work showed that non-obese diabetic (NOD) mice undergoing treatment with aqueous leaf extract of P. alata present reduced insulitis in the pancreas, possibly due to its anti-inflammatory properties. However, depending on the concentration and their ability to interact with other molecules, these phenolic compounds may promote oxidation reactions in some cellular components, such as proteins and lipids, thus presenting a pro-oxidant effect. The present work aimed to evaluate the in vitro effects of aqueous leaf extract of P. alata and its polyphenols (vitexin, isoorientin, rutin and catechin) on lymphocyte proliferation and viability, the cell cycle and oxidative stress. Our results showed that T lymphocytes stimulated with concanavalin A mitogen (ConA) and in the presence of IC50 concentrations of P. alata extract and polyphenols undergo cell injury via inhibition of proliferation, with these effects being more pronounced concerning CD4+ T cells (P. alata, 3.54 ± 0.34%; isoorientin, 57.07 ± 6.4%; vitexin, 16.95 ± 1.11%; catechin, 37.9 ± 4.2% and rutin, 40.14 ± 4.5%), compared to the non-treated group (77.17 ± 6.29) (p < 0.0001 for all comparisons). This process includes late apoptosis/necrosis induction (P. alata, 77.5 ± 0.7%; vitexin, 83 ± 3.3%; isoorientin, 83.8 ± 1.4%; catechin, 83 ± 1.9% and rutin, 74.9 ± 3.2, while the control presented 53.6% ± 3.1 (p < 0.0001 for all comparisons)) and mitochondrial depolarization leading to cell-death induction. Furthermore, an in vitro model of a mixed culture of NOD mice T cells with a mouse pancreatic beta-cell line (MIN6) showed increased intracellular nitric oxide and lipid peroxidation in NOD T cells submitted to P. alata extract (46.41 ± 3.08) compared to the untreated control group (33.57 ± 1.99, p = 0.01315). These results suggest that aqueous leaf extract of P. alata and the polyphenols in these leaves represent a target for translational research showing the plant’s benefits for developing new drugs with immunomodulatory properties against inflammatory diseases such as diabetes mellitus.
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Inhibition Mechanism of Components Isolated from Morus alba Branches on Diabetes and Diabetic Complications via Experimental and Molecular Docking Analyses. Antioxidants (Basel) 2022; 11:antiox11020383. [PMID: 35204264 PMCID: PMC8869400 DOI: 10.3390/antiox11020383] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/09/2022] [Accepted: 02/10/2022] [Indexed: 02/04/2023] Open
Abstract
Previously, we reported the anti-diabetic effect of Morus alba root bark and the compounds therein. In our continuous study of other parts of this plant, the ability of the branch of Morus alba to inhibit α-glucosidase, protein tyrosine phosphatase 1B (PTP1B), and advanced glycation end products (AGEs) formation was evaluated. Moreover, there are no previous studies that have performed enzyme kinetics and molecular docking analyses, along with assessments of peroxynitrite (ONOO−) inhibitory activities. Since the Morus alba branch exhibited favorable inhibitory effects, repeated column chromatography was performed to obtain eight compounds, including four flavonoids (1, 3, 6, 8), one arylbenzofuran (2), one stilbene (5), one Diels–Alder-type adduct (7), and one sterol (4). Among them, compounds 1–3 and 5–7 were mixed-type inhibitors of α-glucosidase, sharing the same catalytic residues with acarbose and the same allosteric sites with (Z)-3-bytylidenephthalide. On the other hand, kuwanon C (1) and oxyresveratrol (5) interacted with residues of the allosteric site (α3 and α6 helices) of PTP1B, indicating their use as non-competitive inhibitors. Interestingly, kuwanon G (7) directly bound the catalytic site, or interrupted the binding between the substrate and the active site, as a mixed-type inhibitor. Moreover, most of the compounds exhibited greater activity against AGE formation and ONOO− than positive controls. The IC50 values required to inhibit ONOO− using compounds 1, 3, 5, 6, and 7 were reported for the first time, and range from 1.08 to 12.92 μM. Based on the structure–activity relationship, the presence of hydroxyl, resorcinol, and prenyl moieties was important in the prevention of diabetes’ pathological mechanisms, and these findings have been further supported by molecular docking analysis. These computational and experimental results will be useful in the development of therapeutic candidates to prevent/treat diabetes and its complications.
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Impairment of IGF-1 Signaling and Antioxidant Response Are Associated with Radiation Sensitivity and Mortality. Int J Mol Sci 2021; 22:ijms22010451. [PMID: 33466349 PMCID: PMC7795011 DOI: 10.3390/ijms22010451] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/19/2020] [Accepted: 12/29/2020] [Indexed: 02/03/2023] Open
Abstract
Following exposure to high doses of ionizing radiation, diverse strains of vertebrate species will manifest varying levels of radiation sensitivity. To understand the inter-strain cellular and molecular mechanisms of radiation sensitivity, two mouse strains with varying radiosensitivity (C3H/HeN, and CD2F1), were exposed to total body irradiation (TBI). Since Insulin-like Growth Factor-1 (IGF-1) signaling pathway is associated with radiosensitivity, we investigated the link between systemic or tissue-specific IGF-1 signaling and radiosensitivity. Adult male C3H/HeN and CD2F1 mice were irradiated using gamma photons at Lethal Dose-70/30 (LD70/30), 7.8 and 9.35 Gy doses, respectively. Those mice that survived up to 30 days post-irradiation, were termed the survivors. Mice that were euthanized prior to 30 days post-irradiation due to deteriorated health were termed decedents. The analysis of non-irradiated and irradiated survivor and decedent mice showed that inter-strain radiosensitivity and post-irradiation survival outcomes are associated with activation status of tissue and systemic IGF-1 signaling, nuclear factor erythroid 2-related factor 2 (Nrf2) activation, and the gene expression profile of cardiac mitochondrial energy metabolism pathways. Our findings link radiosensitivity with dysregulation of IGF-1 signaling, and highlight the role of antioxidant gene response and mitochondrial function in radiation sensitivity.
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Glutathione Peroxidase 1 Promotes NSCLC Resistance to Cisplatin via ROS-Induced Activation of PI3K/AKT Pathway. BIOMED RESEARCH INTERNATIONAL 2019; 2019:7640547. [PMID: 31032363 PMCID: PMC6457285 DOI: 10.1155/2019/7640547] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 02/07/2019] [Accepted: 02/19/2019] [Indexed: 01/15/2023]
Abstract
Purpose Reactive oxygen species (ROS)-induced cytotoxicity is an important mechanism by which cisplatin kills tumor cells. Glutathione peroxidase family (GPXs) is an important member of antioxidant system which metabolizes intracellular ROS and maintains homeostasis of cells. Altered expressions of GPXs enzymes, especially GPX1, have been described in a variety of human cancers. However, their functional roles in cisplatin-based chemoresistance in human malignancies including non-small cell lung cancer have never been explored. Methods A panel of NSCLC cell lines were selected for this study. GPX1 expression was detected using quantitative RT-PCR and Western blot. Cisplatin-induced cell killing was analyzed by CCK8 assay. Intracellular ROS levels were detected by fluorescence-based flow cytometry analysis. In vitro overexpression and knockdown of GPX1 expression were performed using GPX1 expression vector and siRNA approaches. Protein levels of PTEN, NF-κB, BCL2, Bax, and phosphorylated AKT were detected with western blot analysis using specific antibodies. Results GPX1 expression was upregulated in a subset of NSCLC cell lines resistant to cisplatin treatment. Expression vector-mediated forced overexpression of GPX1 significantly increased cisplatin resistance in NSCLC cell lines, whereas RNA inference-mediated downregulation of GPX1 could restore sensitivity to cisplatin. Overexpression of GPX1 significantly suppressed elevation of intracellular ROS and activation of AKT pathway when NSCLC cell lines were exposed to different concentrations of cisplatin. Activation of the AKT pathway inhibited proapoptotic cascade and subsequently led to cisplatin resistance in NSCLC cells. Inhibition of NF-κB by its chemical inhibitor BAY can significantly downregulate GPX1 expression and restore the cisplatin sensitivity of the cell lines resistant to cisplatin. Conclusions Our findings suggested that overexpression of GPX1 is a novel molecular mechanism for cisplatin-based chemoresistance in NSCLC. GPX1 overexpression blocks cisplatin-induced ROS intracellular accumulation, activates PI3K-AKT pathway by increased AKT phosphorylation, and further leads to cisplatin resistance in NSCLC cells. Inhibition of NF-κB signaling may be an alternative approach for restoring cisplatin sensitivity for NSCLC cells resistant to cisplatin-based chemotherapy.
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Yang X, Zhao Y, Sun Q, Yang Y, Gao Y, Ge W, Liu J, Xu X, Zhang J. An Intermediary Role of Adenine Nucleotides on Free Fatty Acids-Induced Hyperglycemia in Obese Mice. Front Endocrinol (Lausanne) 2019; 10:497. [PMID: 31447776 PMCID: PMC6691070 DOI: 10.3389/fendo.2019.00497] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/09/2019] [Indexed: 12/17/2022] Open
Abstract
Increased plasma free fatty acids (FFA) level plays a central role in the development of type 2 diabetes. Our previous studies have shown that plasma 5'-adenosine monophosphate (5'-AMP) elevates and acts as a potential upstream regulator of hyperglycemia in diabetic db/db mice. The relationship between FFA and plasma adenosine nucleotides in type 2 diabetes remains unclear. Here we found that plasma 5'-AMP level was also increased in diabetic mice induced by a high-fat diet and streptozotocin (HFD-STZ), as observed in diabetic db/db mice. The metabolites of adenosine nucleotides in plasma were increased in obese mice compared to lean mice. An acute oil gavage to lean mice increased both FFA and plasma purine metabolites, accompanying with glucose intolerance. 5'-AMP administration resulted in an increase in dose-dependent purine metabolites and different levels of glucose intolerance. FFA induced a release of adenine nucleotides from cultural human umbilical vein endothelial cells (HUVECs) prior to induction of their apoptosis. FFA also reduced red blood cells (RBCs) resistance to reactive oxygen species (ROS), leading to hemolysis, thereby increasing plasma nucleotides. Our results suggest that plasma adenine nucleotides play an intermediary role in FFA-induced glucose intolerance and hyperglycemia in obese mice.
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Chronic stress of high dietary carbohydrate level causes inflammation and influences glucose transport through SOCS3 in Japanese flounder Paralichthys olivaceus. Sci Rep 2018; 8:7415. [PMID: 29743495 PMCID: PMC5943576 DOI: 10.1038/s41598-018-25412-w] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 03/13/2018] [Indexed: 02/06/2023] Open
Abstract
Carnivorous fish is thought to be high-glucose intolerance. But the reasons were still unclear. The aim of the present study is to investigate the effects of high level of dietary carbohydrate on the survival, growth and immune responses of Paralichthys olivaceus, and the underlying molecular mechanism related to the immune and glucose metabolism. P. olivaceus were fed with 8%, 16% and 24% of dietary carbohydrate for 10 weeks, respectively. After that, a glucose tolerance test (GTT) was conducted. Results showed that excessive (24%) dietary carbohydrate significantly decreased the growth and glucose tolerance ability according to the GTT. It significantly increased hepatic NADPH oxidase activity and malondialdehyde content and serum contents of IL-6 and advanced glycation end products. The expressions of glucose transport-relevant genes in liver and the content of related hormones in serum were analyzed. In conclusion, it was confirmed that IL-6 increased the expression of suppressor of cytokine signaling 3 (SOCS3) and regulated the downstream targets of PI3K-AKT mediated signal transduction, and then downregulated the glucose transporter 2 activity in liver of P. olivaceus fed diet with excessive carbohydrate level. It was suggested that SOCS3 served as a bridge between immune response and glucose metabolism in P. olivaceus.
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Reductive Stress in Inflammation-Associated Diseases and the Pro-Oxidant Effect of Antioxidant Agents. Int J Mol Sci 2017; 18:ijms18102098. [PMID: 28981461 PMCID: PMC5666780 DOI: 10.3390/ijms18102098] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 09/16/2017] [Accepted: 09/30/2017] [Indexed: 12/18/2022] Open
Abstract
Abstract: Reductive stress (RS) is the counterpart oxidative stress (OS), and can occur in response to conditions that shift the redox balance of important biological redox couples, such as the NAD⁺/NADH, NADP⁺/NADPH, and GSH/GSSG, to a more reducing state. Overexpression of antioxidant enzymatic systems leads to excess reducing equivalents that can deplete reactive oxidative species, driving the cells to RS. A feedback regulation is established in which chronic RS induces OS, which in turn, stimulates again RS. Excess reducing equivalents may regulate cellular signaling pathways, modify transcriptional activity, induce alterations in the formation of disulfide bonds in proteins, reduce mitochondrial function, decrease cellular metabolism, and thus, contribute to the development of some diseases in which NF-κB, a redox-sensitive transcription factor, participates. Here, we described the diseases in which an inflammatory condition is associated to RS, and where delayed folding, disordered transport, failed oxidation, and aggregation are found. Some of these diseases are aggregation protein cardiomyopathy, hypertrophic cardiomyopathy, muscular dystrophy, pulmonary hypertension, rheumatoid arthritis, Alzheimer's disease, and metabolic syndrome, among others. Moreover, chronic consumption of antioxidant supplements, such as vitamins and/or flavonoids, may have pro-oxidant effects that may alter the redox cellular equilibrium and contribute to RS, even diminishing life expectancy.
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Dose-dependent effect of Bisphenol-A on insulin signaling molecules in cardiac muscle of adult male rat. Chem Biol Interact 2017; 266:10-16. [DOI: 10.1016/j.cbi.2017.01.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/20/2017] [Accepted: 01/26/2017] [Indexed: 01/16/2023]
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Effects of methyl mercury on the activity and gene expression of mouse Langerhans islets and glucose metabolism. Food Chem Toxicol 2016; 93:119-28. [DOI: 10.1016/j.fct.2016.05.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 04/29/2016] [Accepted: 05/06/2016] [Indexed: 01/01/2023]
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Gounden S, Phulukdaree A, Moodley D, Chuturgoon A. Increased SIRT3 Expression and Antioxidant Defense under Hyperglycemic Conditions in HepG2 Cells. Metab Syndr Relat Disord 2015; 13:255-63. [DOI: 10.1089/met.2014.0140] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Shivona Gounden
- Discipline of Medical Biochemistry, University of KwaZulu-Natal, Durban, South Africa
| | - Alisa Phulukdaree
- Discipline of Medical Biochemistry, University of KwaZulu-Natal, Durban, South Africa
| | - Devapregasan Moodley
- Discipline of Medical Biochemistry, University of KwaZulu-Natal, Durban, South Africa
| | - Anil Chuturgoon
- Discipline of Medical Biochemistry, University of KwaZulu-Natal, Durban, South Africa
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Jiang S, Wang Y, Ren D, Li J, Yuan G, An L, Du P, Ma J. Antidiabetic mechanism of Coptis chinensis polysaccharide through its antioxidant property involving the JNK pathway. PHARMACEUTICAL BIOLOGY 2015; 53:1022-1029. [PMID: 25858018 DOI: 10.3109/13880209.2014.952838] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
CONTEXT Antidiabetic activity of Coptis chinensis Franch (Ranunculaceae) polysaccharide (CCPW) has been reported. However, its molecular mechanism remains unclear. OBJECTIVE An attempt was made to further verify the antidiabetic activity of CCPW on type 2 diabetes mellitus (T2DM) and elucidate the mechanism of antidiabetic activity. MATERIALS AND METHODS Male Wistar rats were fed with high-fat diet (HFD) and injected with streptozotocin (STZ) to generate a T2DM model. Effects of CCPW on fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), glutathione (GSH), glutathione peroxidases (GSH-Px), superoxide dismutases (SOD), catalase (CAT), malondialdehyde (MDA), c-jun n-terminal kinase (JNK), phosphorylated insulin receptor substrate 1 (phospho-IRS1), phosphorylated phosphatidylinositol 3 kinase (phospho-PI3Kp85) and glucose transporter 4 (Glut4) were investigated. RESULTS FBG level of diabetic rats could be significantly inhibited by 51.2, 42.7, and 23.3% through administration of CCPW at doses of 200, 100, and 50 mg/kg b.w., respectively (p < 0.01). CCPW also could significantly reduce TG by 19.2, 12.1, and 7.4%, and TC by 24.2, 20.9, and 18.7%, respectively (p < 0.05 or p < 0.01). CCPW showed an obvious antioxidant effect through increasing GSH-Px, SOD, and CAT activities, and decreasing GSH and MDA contents (p < 0.05 or p < 0.01). Furthermore, CCPW could inhibit JNK and phospho-IRS1 expression and promote the expression of phospho-PI3Kp85 and Glut4 compared with those in the DM group (p < 0.05 or p < 0.01). DISCUSSION AND CONCLUSION CCPW can produce antidiabetic activity in rats with T2DM through its antioxidative effect, which is closely related to the JNK/IRS1/PI3K pathway.
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Affiliation(s)
- Shuang Jiang
- College of Basic Medical Sciences, Changchun University of Chinese Medicine , Changchun, Jilin , PR China
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Aon MA, Tocchetti CG, Bhatt N, Paolocci N, Cortassa S. Protective mechanisms of mitochondria and heart function in diabetes. Antioxid Redox Signal 2015; 22:1563-86. [PMID: 25674814 PMCID: PMC4449630 DOI: 10.1089/ars.2014.6123] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
SIGNIFICANCE The heart depends on continuous mitochondrial ATP supply and maintained redox balance to properly develop force, particularly under increased workload. During diabetes, however, myocardial energetic-redox balance is perturbed, contributing to the systolic and diastolic dysfunction known as diabetic cardiomyopathy (DC). CRITICAL ISSUES How these energetic and redox alterations intertwine to influence the DC progression is still poorly understood. Excessive bioavailability of both glucose and fatty acids (FAs) play a central role, leading, among other effects, to mitochondrial dysfunction. However, where and how this nutrient excess affects mitochondrial and cytoplasmic energetic/redox crossroads remains to be defined in greater detail. RECENT ADVANCES We review how high glucose alters cellular redox balance and affects mitochondrial DNA. Next, we address how lipid excess, either stored in lipid droplets or utilized by mitochondria, affects performance in diabetic hearts by influencing cardiac energetic and redox assets. Finally, we examine how the reciprocal energetic/redox influence between mitochondrial and cytoplasmic compartments shapes myocardial mechanical activity during the course of DC, focusing especially on the glutathione and thioredoxin systems. FUTURE DIRECTIONS Protecting mitochondria from losing their ability to generate energy, and to control their own reactive oxygen species emission is essential to prevent the onset and/or to slow down DC progression. We highlight mechanisms enforced by the diabetic heart to counteract glucose/FAs surplus-induced damage, such as lipid storage, enhanced mitochondria-lipid droplet interaction, and upregulation of key antioxidant enzymes. Learning more on the nature and location of mechanisms sheltering mitochondrial functions would certainly help in further optimizing therapies for human DC.
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Affiliation(s)
- Miguel A Aon
- Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Carlo G Tocchetti
- Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Niraj Bhatt
- Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Nazareno Paolocci
- Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Sonia Cortassa
- Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Differential thiol oxidation of the signaling proteins Akt, PTEN or PP2A determines whether Akt phosphorylation is enhanced or inhibited by oxidative stress in C2C12 myotubes derived from skeletal muscle. Int J Biochem Cell Biol 2015; 62:72-9. [DOI: 10.1016/j.biocel.2015.02.015] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 02/17/2015] [Accepted: 02/20/2015] [Indexed: 11/17/2022]
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17
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Bahadar H, Maqbool F, Mostafalou S, Baeeri M, Rahimifard M, Navaei-Nigjeh M, Abdollahi M. Assessment of benzene induced oxidative impairment in rat isolated pancreatic islets and effect on insulin secretion. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2015; 39:1161-1169. [PMID: 25935538 DOI: 10.1016/j.etap.2015.04.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 04/04/2015] [Accepted: 04/10/2015] [Indexed: 06/04/2023]
Abstract
Benzene (C6H6) is an organic compound used in petrochemicals and numerous other industries. It is abundantly released to our environment as a chemical pollutant causing widespread human exposure. This study mainly focused on benzene induced toxicity on rat pancreatic islets with respect to oxidative damage, insulin secretion and glucokinase (GK) activity. Benzene was dissolved in corn oil and administered orally at doses 200, 400 and 800mg/kg/day, for 4 weeks. In rats, benzene significantly raised the concentration of plasma insulin. Also the effect of benzene on the release of glucose-induced insulin was pronounced in isolated islets. Benzene caused oxidative DNA damage and lipid peroxidation, and also reduced the cell viability and total thiols groups, in the islets of exposed rats. In conclusion, the current study revealed that pancreatic glucose metabolism is susceptible to benzene toxicity and the resultant oxidative stress could lead to functional abnormalities in the pancreas.
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Affiliation(s)
- Haji Bahadar
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Faheem Maqbool
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Sara Mostafalou
- School of Pharmacy, Ardebil University of Medical Sciences, Ardebil, Iran
| | - Maryam Baeeri
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Mahban Rahimifard
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mona Navaei-Nigjeh
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Abdollahi
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran; Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
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18
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Gremmels H, Bevers LM, Fledderus JO, Braam B, van Zonneveld AJ, Verhaar MC, Joles JA. Oleic acid increases mitochondrial reactive oxygen species production and decreases endothelial nitric oxide synthase activity in cultured endothelial cells. Eur J Pharmacol 2015; 751:67-72. [PMID: 25595727 DOI: 10.1016/j.ejphar.2015.01.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 12/23/2014] [Accepted: 01/06/2015] [Indexed: 02/07/2023]
Abstract
Elevated plasma levels of free fatty acids (FFA) are associated with increased cardiovascular risk. This may be related to FFA-induced elevation of oxidative stress in endothelial cells. We hypothesized that, in addition to mitochondrial production of reactive oxygen species, endothelial nitric oxide synthase (eNOS)-mediated reactive oxygen species production contributes to oleic acid (OA)-induced oxidative stress in endothelial cells, due to eNOS uncoupling. We measured reactive oxygen species production and eNOS activity in cultured endothelial cells (bEnd.3) in the presence of OA bound to bovine serum albumin, using the CM-H2DCFDA assay and the L-arginine/citrulline conversion assay, respectively. OA induced a concentration-dependent increase in reactive oxygen species production, which was inhibited by the mitochondrial complex II inhibitor thenoyltrifluoroacetone (TTFA). OA had little effect on eNOS activity when stimulated by a calcium-ionophore, but decreased both basal and insulin-induced eNOS activity, which was restored by TTFA. Pretreatment of bEnd.3 cells with tetrahydrobiopterin (BH4) prevented OA-induced reactive oxygen species production and restored inhibition of eNOS activity by OA. Elevation of OA levels leads to both impairment in receptor-mediated stimulation of eNOS and to production of mitochondrial-derived reactive oxygen species and hence endothelial dysfunction.
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Affiliation(s)
- Hendrik Gremmels
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Lonneke M Bevers
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Joost O Fledderus
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Branko Braam
- Department of Medicine, Division of Nephrology and Immunology, University of Alberta Hospital, Edmonton, Canada; Department of Physiology, University of Alberta, Edmonton, Canada
| | - Anton Jan van Zonneveld
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marianne C Verhaar
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jaap A Joles
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands.
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19
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Mesarwi OA, Sharma EV, Jun JC, Polotsky VY. Metabolic dysfunction in obstructive sleep apnea: A critical examination of underlying mechanisms. Sleep Biol Rhythms 2014; 13:2-17. [PMID: 26412981 DOI: 10.1111/sbr.12078] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
It has recently become clear that obstructive sleep apnea (OSA) is an independent risk factor for the development of metabolic syndrome, a disorder of defective energy storage and use. Several mechanisms have been proposed to explain this finding, drawing upon the characteristics that define OSA. In particular, intermittent hypoxia, sleep fragmentation, elevated sympathetic tone, and oxidative stress - all consequences of OSA - have been implicated in the progression of poor metabolic outcomes in OSA. In this review we examine the evidence to support each of these disease manifestations of OSA as a unique risk for metabolic dysfunction. Tissue hypoxia and sleep fragmentation are each directly connected to insulin resistance and hypertension, and each of these also may increase sympathetic tone, resulting in defective glucose homeostasis, excessive lipolysis, and elevated blood pressure. Oxidative stress further worsens insulin resistance and in turn, metabolic dysfunction also increases oxidative stress. However, despite many studies linking each of these individual components of OSA to the development of metabolic syndrome, there are very few reports that actually provide a coherent narrative about the mechanism underlying metabolic dysfunction in OSA.
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Affiliation(s)
- Omar A Mesarwi
- Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Jonathan C Jun
- Johns Hopkins University School of Medicine, Baltimore, Maryland
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20
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Higashi Y, Quevedo HC, Tiwari S, Sukhanov S, Shai SY, Anwar A, Delafontaine P. Interaction between insulin-like growth factor-1 and atherosclerosis and vascular aging. FRONTIERS OF HORMONE RESEARCH 2014; 43:107-24. [PMID: 24943302 DOI: 10.1159/000360571] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The process of vascular aging encompasses alterations in the function of endothelial (ECs) and vascular smooth muscle cells (VSMCs) via oxidation, inflammation, cell senescence and epigenetic modifications, increasing the probability of atherosclerosis. Aged vessels exhibit decreased endothelial antithrombogenic properties, increased reactive oxygen species generation, inflammatory signaling and migration of VSMCs to the subintimal space, impaired angiogenesis and increased elastin degradation. The key initiating step in atherogenesis is subendothelial accumulation of apolipoprotein B-containing low-density lipoproteins resulting in activation of ECs and recruitment of monocytes. Activated ECs secrete 'chemokines' that interact with cognate chemokine receptors on monocytes and promote directional migration. Recruitment of immune cells establishes a proinflammatory status, further causing elevated oxidative stress, which in turn triggers a series of events including apoptotic or necrotic death of vascular and nonvascular cells. Increased oxidative stress is also considered to be a key factor in mechanisms of aging-associated changes in tissue integrity and function. Experimental evidence indicates that insulin-like growth factor-1 exerts antioxidant, anti-inflammatory and pro-survival effects on the vasculature, reducing atherosclerotic plaque burden and promoting features of atherosclerotic plaque stability.
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Affiliation(s)
- Yusuke Higashi
- Tulane University School of Medicine, Tulane University Heart and Vascular Institute, New Orleans, La., USA
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21
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Anti-diabetic effects of benfotiamine on an animal model of type 2 diabetes mellitus. ACTA ACUST UNITED AC 2014. [DOI: 10.14405/kjvr.2014.54.1.21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Gratas-Delamarche A, Derbré F, Vincent S, Cillard J. Physical inactivity, insulin resistance, and the oxidative-inflammatory loop. Free Radic Res 2013; 48:93-108. [PMID: 24060092 DOI: 10.3109/10715762.2013.847528] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Epidemiological data indicate that physical inactivity, a main factor of global energetic imbalance, is involved in the worldwide epidemic of obesity and metabolic disorders such as insulin resistance. Although the complex pathogenesis of insulin resistance is not fully understood, literature data accumulated during the past decades clearly indicate that the activation of the oxidative-inflammatory loop plays a major role. By activating the oxidative-inflammatory loop in insulin-sensitive tissues, fat gain and adipose tissue dysfunction likely contribute to induce insulin resistance during chronic and prolonged physical inactivity. However, in the past years, evidence has emerged showing that early insulin resistance also occurs after very short-term exposure to physical inactivity (1-7 days) without any fat gain or energetic imbalance. The possible role of liver disturbances or endothelial dysfunction is suggested, but further studies are necessary to really conclude. Inactive skeletal muscle probably constitutes the primary triggering tissue for the development of early insulin resistance. In the present review, we discuss on the current knowledge about the effect of physical inactivity on whole-body and peripheral insulin sensitivity, and how local inflammation and oxidative stress arising with physical inactivity could potentially induce insulin resistance. We assume that early muscle insulin resistance allows the excess nutrients to shift in the storage tissues to withstand starvation through energy storage. We also consider when chronic and prolonged, physical inactivity over an extended period of time is an underestimated contributor to pathological insulin resistance and hence indirectly to numerous chronic diseases.
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Affiliation(s)
- A Gratas-Delamarche
- University Rennes 2 - ENS Cachan - Antenne de Bretagne, Laboratory "Movement, Sport and Health Sciences" (M2S) , Rennes , France
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23
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Pomytkin IA. H2O2 Signalling Pathway: A Possible Bridge between Insulin Receptor and Mitochondria. Curr Neuropharmacol 2013; 10:311-20. [PMID: 23730255 PMCID: PMC3520041 DOI: 10.2174/157015912804143559] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 06/07/2012] [Accepted: 06/24/2012] [Indexed: 01/20/2023] Open
Abstract
This review is focused on the mechanistic aspects of the insulin-induced H2O2 signalling pathway in neurons and the molecules affecting it, which act as risk factors for developing central insulin resistance. Insulin-induced H2O2 promotes insulin receptor activation and the mitochondria act as the insulin-sensitive H2O2 source, providing a direct molecular link between mitochondrial dysfunction and irregular insulin receptor activation. In this view, the accumulation of dysfunctional mitochondria during chronological ageing and Alzheimer's disease (AD) is a risk factor that may contribute to the development of dysfunctional cerebral insulin receptor signalling and insulin resistance. Due to the high significance of insulin-induced H2O2 for insulin receptor activation, oxidative stress-induced upregulation of antioxidant enzymes, e.g., in AD brains, may represent another risk factor contributing to the development of insulin resistance. As insulin-induced H2O2 signalling requires fully functional mitochondria, pharmacological strategies based on activating mitochondria biogenesis in the brain are central to the treatment of diseases associated with dysfunctional insulin receptor signalling in this organ.
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24
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Styskal J, Nwagwu FA, Watkins YN, Liang H, Richardson A, Musi N, Salmon AB. Methionine sulfoxide reductase A affects insulin resistance by protecting insulin receptor function. Free Radic Biol Med 2013; 56:123-32. [PMID: 23089224 PMCID: PMC3578155 DOI: 10.1016/j.freeradbiomed.2012.10.544] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 10/07/2012] [Accepted: 10/15/2012] [Indexed: 02/06/2023]
Abstract
Oxidative stress plays a significant role in the development of insulin resistance; however, the cellular targets of oxidation that cause insulin resistance have yet to be fully elucidated. Methionine sulfoxide reductases reduce oxidized methionine residues, thereby repairing and protecting proteins from oxidation. Recently, several genome-wide analyses have found human obesity to be strongly correlated with polymorphisms near the methionine sulfoxide reductase A (MsrA) locus. In this study, we tested whether modulation of MsrA expression significantly alters the development of obesity and/or insulin resistance in mice. We show that mice lacking MsrA (MsrA(-/-)) are prone to the development of high-fat-diet-induced insulin resistance and a reduced physiological insulin response compared to high-fat-fed wild-type mice. We also show that oxidative stress in C2C12 cell cultures reduces both insulin-stimulated phosphorylation and autophosphorylation of the insulin receptor. Tissues from high-fat-fed mice show similar reduction in insulin receptor function and increase in insulin receptor oxidation, which are further exacerbated by the lack of MsrA. Together, these data demonstrate for the first time that MsrA and protein oxidation play a role in the regulation of glucose homeostasis. In addition, these data support a novel hypothesis that obesity-induced insulin resistance is caused in part by reduced function of insulin signaling proteins arising from protein oxidation.
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Affiliation(s)
- JennaLynn Styskal
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Cellular & Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Florence A. Nwagwu
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Yvonne N. Watkins
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Hanyu Liang
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Division of Diabetes, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Arlan Richardson
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Cellular & Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, 78229
| | - Nicolas Musi
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Division of Diabetes, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, 78229
| | - Adam B. Salmon
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, 78229
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25
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Teodoro JS, Rolo AP, Palmeira CM. The NAD ratio redox paradox: why does too much reductive power cause oxidative stress? Toxicol Mech Methods 2013; 23:297-302. [PMID: 23256455 DOI: 10.3109/15376516.2012.759305] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The reductive power provided by nicotinamide adenine dinucleotides is invaluable for several cellular processes. It drives metabolic reactions, enzymatic activity, regulates genetic expression and allows for the maintenance of a normal cell redox status. Therefore, the balance between the oxidized (NAD(+)) and the reduced (NADH) forms is critical for the cell's proper function and ultimately, for its survival. Being intimately associated with the cells' metabolism, it is expected that alterations to the NAD(+)/NADH ratio are to be found in situations of metabolic diseases, as is the case of diabetes. NAD(+) is a necessary cofactor for several enzymes' activity, many of which are related to metabolism. Therefore, a decrease in the NAD(+)/NADH ratio causes these enzymes to decrease in activity (reductive stress), resulting in an altered metabolic situation that might be the first insult toward several pathologies, such as diabetes. Here, we review the importance of nicotinamide adenine dinucleotides in the liver cell and its fluctuations in a state of type 2 diabetes mellitus.
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Affiliation(s)
- João Soeiro Teodoro
- Center for Neurosciences and Cell Biology, Department of Life Sciences of the University of Coimbra , Coimbra , Portugal
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26
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Salmon AB. Oxidative stress in the etiology of age-associated decline in glucose metabolism. LONGEVITY & HEALTHSPAN 2012; 1:7. [PMID: 24764512 PMCID: PMC3922939 DOI: 10.1186/2046-2395-1-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 07/09/2012] [Indexed: 12/25/2022]
Abstract
One of the most common pathologies in aging humans is the development of glucose metabolism dysfunction. The high incidence of metabolic dysfunction, in particular type 2 diabetes mellitus, is a significant health and economic burden on the aging population. However, the mechanisms that regulate this age-related physiological decline, and thus potential preventative treatments, remain elusive. Even after accounting for age-related changes in adiposity, lean mass, blood lipids, etc., aging is an independent factor for reduced glucose tolerance and increased insulin resistance. Oxidative stress has been shown to have significant detrimental impacts on the regulation of glucose homeostasis in vitro and in vivo. Furthermore, oxidative stress has been shown to be modulated by age and diet in several model systems. This review provides an overview of these data and addresses whether increases in oxidative stress with aging may be a primary determinant of age-related metabolic dysfunction.
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Affiliation(s)
- Adam B Salmon
- The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, Audie L. Murphy Hospital, San Antonio, TX, 78229, USA ; Department of Molecular Medicine, The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, 15355 Lambda Drive, MSC 7755, San Antonio, TX, 78245-3207, USA
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27
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Abstract
Hypertension is a leading cause of morbidity and mortality worldwide. Individuals with hypertension are at an increased risk for stroke, heart disease and kidney failure. Essential hypertension results from a combination of genetic and lifestyle factors. One such lifestyle factor is diet, and its role in the control of blood pressure has come under much scrutiny. Just as increased salt and sugar are known to elevate blood pressure, other dietary factors may have antihypertensive effects. Studies including the Optimal Macronutrient Intake to Prevent Heart Disease (OmniHeart) study, Multiple Risk Factor Intervention Trial (MRFIT), International Study of Salt and Blood Pressure (INTERSALT) and Dietary Approaches to Stop Hypertension (DASH) study have demonstrated an inverse relationship between dietary protein and blood pressure. One component of dietary protein that may partially account for its antihypertensive effect is the nonessential amino acid cysteine. Studies in hypertensive humans and animal models of hypertension have shown that N-acetylcysteine, a stable cysteine analogue, lowers blood pressure, which substantiates this idea. Cysteine may exert its antihypertensive effects directly or through its storage form, glutathione, by decreasing oxidative stress, improving insulin resistance and glucose metabolism, lowering advanced glycation end products, and modulating levels of nitric oxide and other vasoactive molecules. Therefore, adopting a balanced diet containing cysteine-rich proteins may be a beneficial lifestyle choice for individuals with hypertension. An example of such a diet is the DASH diet, which is low in salt and saturated fat; includes whole grains, poultry, fish and nuts; and is rich in vegetables, fruits and low-fat dairy products.
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Affiliation(s)
- Sudesh Vasdev
- Discipline of Medicine, Faculty of Medicine, Health Sciences Centre, Memorial University, St John's, Newfoundland
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28
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Higashi Y, Sukhanov S, Anwar A, Shai SY, Delafontaine P. Aging, atherosclerosis, and IGF-1. J Gerontol A Biol Sci Med Sci 2012; 67:626-39. [PMID: 22491965 PMCID: PMC3348497 DOI: 10.1093/gerona/gls102] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 03/01/2012] [Indexed: 12/18/2022] Open
Abstract
Insulin-like growth factor 1 (IGF-1) is an endocrine and autocrine/paracrine growth factor that circulates at high levels in the plasma and is expressed in most cell types. IGF-1 has major effects on development, cell growth and differentiation, and tissue repair. Recent evidence indicates that IGF-1 reduces atherosclerosis burden and improves features of atherosclerotic plaque stability in animal models. Potential mechanisms for this atheroprotective effect include IGF-1-induced reduction in oxidative stress, cell apoptosis, proinflammatory signaling, and endothelial dysfunction. Aging is associated with increased vascular oxidative stress and vascular disease, suggesting that IGF-1 may exert salutary effects on vascular aging processes. In this review, we will provide a comprehensive update on IGF-1's ability to modulate vascular oxidative stress and to limit atherogenesis and the vascular complications of aging.
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Affiliation(s)
- Yusuke Higashi
- Tulane University Heart & Vascular Institute, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA
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29
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D’Cruz SC, Jubendradass R, Jayakanthan M, Rani SJA, Mathur PP. Bisphenol A impairs insulin signaling and glucose homeostasis and decreases steroidogenesis in rat testis: An in vivo and in silico study. Food Chem Toxicol 2012; 50:1124-33. [DOI: 10.1016/j.fct.2011.11.041] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Revised: 11/22/2011] [Accepted: 11/22/2011] [Indexed: 10/14/2022]
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30
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Styskal J, Van Remmen H, Richardson A, Salmon AB. Oxidative stress and diabetes: what can we learn about insulin resistance from antioxidant mutant mouse models? Free Radic Biol Med 2012; 52:46-58. [PMID: 22056908 PMCID: PMC3249484 DOI: 10.1016/j.freeradbiomed.2011.10.441] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 10/12/2011] [Accepted: 10/13/2011] [Indexed: 01/18/2023]
Abstract
The development of metabolic dysfunctions like diabetes and insulin resistance in mammals is regulated by a myriad of factors. Oxidative stress seems to play a central role in this process as recent evidence shows a general increase in oxidative damage and a decrease in oxidative defense associated with several metabolic diseases. These changes in oxidative stress can be directly correlated with increased fat accumulation, obesity, and consumption of high-calorie/high-fat diets. Modulation of oxidant protection through either genetic mutation or treatment with antioxidants can significantly alter oxidative stress resistance and accumulation of oxidative damage in laboratory rodents. Antioxidant mutant mice have previously been utilized to examine the role of oxidative stress in other disease models, but have been relatively unexplored as models to study the regulation of glucose metabolism. In this review, we will discuss the evidence for oxidative stress as a primary mechanism linking obesity and metabolic disorders and whether alteration of antioxidant status in laboratory rodents can significantly alter the development of insulin resistance or diabetes.
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Affiliation(s)
- Jennalynn Styskal
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78245-3207, USA
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31
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Schinzari F, Tesauro M, Rovella V, Galli A, Mores N, Porzio O, Lauro D, Cardillo C. Generalized impairment of vasodilator reactivity during hyperinsulinemia in patients with obesity-related metabolic syndrome. Am J Physiol Endocrinol Metab 2010; 299:E947-52. [PMID: 20923961 DOI: 10.1152/ajpendo.00426.2010] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Defective insulin-dependent vasodilation might contribute importantly to metabolic and vascular abnormalities of the metabolic syndrome (MetS). However, despite extensive investigation, the precise mechanisms involved in insulin's vasoactive effects have not been fully elucidated. Therefore, this study sought to better characterize insulin's physiological actions on vascular reactivity and their potential derangement in the MetS. Forearm blood flow responses to graded doses of acetylcholine, sodium nitroprusside, and verapamil were assessed by strain-gauge plethysmography in patients with obesity-related MetS (n = 20) and in matched controls (n = 18) before and after intra-arterial infusion of insulin (0.2 mU·kg(-1)·min(-1)). Possible involvement of increased oxidative stress in the impaired insulin-stimulated vasodilator responsiveness of patients with MetS (n = 12) was also investigated using vitamin C (25 mg/min). In control subjects, significant potentiation of the vasodilator responses to acetylcholine, nitroprusside, and verapamil was observed after insulin infusion (all P < 0.05). However, no significant change in vasodilator reactivity to either of these drugs was observed following hyperinsulinemia in patients with MetS (all P > 0.05). Interestingly, administration of vitamin C to patients with MetS during hyperinsulinemia significantly enhanced the vasodilator responsiveness to acetylcholine, nitroprusside, and verapamil (all P < 0.05 vs. hyperinsulinemia alone). In conclusion, insulin exerts a generalized facilitatory action on vasodilator reactivity, and this effect is impaired in patients with MetS likely because of increased oxidative stress. Given the importance of vasodilator reactivity in affecting glucose disposal and vascular homeostasis, this defect may then contribute to the development of metabolic and vascular complications in insulin-resistant states.
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32
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Higashi Y, Sukhanov S, Anwar A, Shai SY, Delafontaine P. IGF-1, oxidative stress and atheroprotection. Trends Endocrinol Metab 2010; 21:245-54. [PMID: 20071192 PMCID: PMC2848911 DOI: 10.1016/j.tem.2009.12.005] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 12/10/2009] [Accepted: 12/11/2009] [Indexed: 01/30/2023]
Abstract
Atherosclerosis is a chronic inflammatory disease in which early endothelial dysfunction and subintimal modified lipoprotein deposition progress to complex, advanced lesions that are predisposed to erosion, rupture and thrombosis. Oxidative stress plays a crucial role not only in initial lesion formation but also in lesion progression and destabilization. Although most growth factors are thought to promote vascular smooth muscle cell proliferation and migration, thereby increasing neointima, recent animal studies indicate that insulin-like growth factor (IGF)-1 exerts both pleiotropic anti-oxidant effects and anti-inflammatory effects, which together reduce atherosclerotic burden. This review discusses the effects of IGF-1 in models of vascular injury and atherosclerosis, emphasizing the relationship between oxidative stress and potential atheroprotective actions of IGF-1.
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Affiliation(s)
- Yusuke Higashi
- Tulane University School of Medicine, 1430 Tulane Avenue, SL 48, New Orleans, LA 70112, USA
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Lastra G, Habibi J, Whaley-Connell AT, Manrique C, Hayden MR, Rehmer J, Patel K, Ferrario C, Sowers JR. Direct renin inhibition improves systemic insulin resistance and skeletal muscle glucose transport in a transgenic rodent model of tissue renin overexpression. Endocrinology 2009; 150:2561-8. [PMID: 19246535 PMCID: PMC2689809 DOI: 10.1210/en.2008-1391] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Renin is the rate-limiting enzyme in renin-angiotensin system (RAS) activation. We sought to determine the impact of renin inhibition on whole-body insulin sensitivity and skeletal muscle RAS, oxidative stress, insulin signaling, and glucose transport in the transgenic TG(mRen2)27 rat (Ren2), which manifests increased tissue RAS activity, elevated serum aldosterone, hypertension, and insulin resistance. Young (aged 6-9 wk) Ren2 and age-matched Sprague Dawley control rats were treated with aliskiren [50 mg/kg . d, ip] or placebo for 21 d and administered an ip glucose tolerance test. Insulin metabolic signaling and 2-deoxyglucose uptake in soleus muscle were examined in relation to tissue renin-angiotensin-aldosterone system [angiotensin (Ang) II, mineralocorticoid receptor (MR), and Ang type I receptor (AT(1)R)] and measures of oxidative stress as well as structural changes evaluated by light and transmission electron microscopy. Ren2 rats demonstrated systemic insulin resistance with decreased skeletal muscle insulin metabolic signaling and glucose uptake. This was associated with increased Ang II, MR, AT(1)R, oxidative stress, and reduced tyrosine insulin receptor substrate-1 phosphorylation, protein kinase B/(Akt) phosphorylation and glucose transporter-4 immunostaining. The Ren2 also demonstrated perivascular fibrosis and mitochondrial remodeling. Renin inhibition improved systemic insulin sensitivity, insulin metabolic signaling, and glucose transport along with normalization of Ang II, AT(1)R, and MR levels, oxidative stress markers, fibrosis, and mitochondrial structural abnormalities. Our data suggest that renin inhibition improves systemic insulin sensitivity, skeletal muscle insulin metabolic signaling, and glucose transport in Ren2 rats. This is associated with reductions in skeletal muscle tissue Ang II, AT(1)R, and MR expression; oxidative stress; fibrosis; and mitochondrial abnormalities.
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Affiliation(s)
- Guido Lastra
- Department of Internal Medicine, University of Missouri-Columbia School of Medicine, Columbia, Missouri 65212, USA
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Kobayashi H, Matsuda M, Fukuhara A, Komuro R, Shimomura I. Dysregulated glutathione metabolism links to impaired insulin action in adipocytes. Am J Physiol Endocrinol Metab 2009; 296:E1326-34. [PMID: 19366877 DOI: 10.1152/ajpendo.90921.2008] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Oxidative stress plays an important role in obesity-related metabolic diseases. Glutathione peroxidase (GPX) is an antioxidant enzyme downregulated in adipose tissue of obese mice. However, the role of GPX in adipocytes remains elusive. The objective of this study was to clarify the pathophysiological changes in GPX activity and glutathione metabolism and their roles in the pathogenesis of insulin resistance in adipocytes. To achieve this goal, we measured cellular GPX activity, glutathione (GSH) contents, GSH/GSSG ratio, and mRNA expression of gamma-glutamylcysteine synthetase (gamma-GCS), a rate-limiting enzyme for de novo GSH synthesis, in adipose tissue of control and ob/ob mice and in 3T3-L1 adipocytes treated with insulin, H(2)O(2), free fatty acid (FFA), or TNFalpha. Furthermore, we investigated the effects of GPX inhibition with a specific GPX inhibitor or RNA interference against GPX, H(2)O(2), and reduced GSH on insulin signaling in 3T3-L1 adipocytes. ob/ob Mice showed not only a decrease in cellular activity of GPXs (GPX1, -4, and -7) but also an increase in gamma-GCS expression, resulting in increased GSH contents in adipose tissue. These alterations in glutathione metabolism were also observed during differentiation of 3T3-L1 cells and their exposure to insulin, FFA, or H(2)O(2). Inhibition of GPX activity, addition of GSH, and H(2)O(2) resulted in impaired insulin signaling in 3T3-L1 adipocytes. These results suggest that decreased GPX activity and increased gamma-GCS expression lead to overaccumulation of GSH, which might be involved in the pathogenesis of insulin resistance in obesity.
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Affiliation(s)
- Hironori Kobayashi
- Dept. of Metabolic Medicine, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
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Bashan N, Kovsan J, Kachko I, Ovadia H, Rudich A. Positive and negative regulation of insulin signaling by reactive oxygen and nitrogen species. Physiol Rev 2009; 89:27-71. [PMID: 19126754 DOI: 10.1152/physrev.00014.2008] [Citation(s) in RCA: 351] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Regulated production of reactive oxygen species (ROS)/reactive nitrogen species (RNS) adequately balanced by antioxidant systems is a prerequisite for the participation of these active substances in physiological processes, including insulin action. Yet, increasing evidence implicates ROS and RNS as negative regulators of insulin signaling, rendering them putative mediators in the development of insulin resistance, a common endocrine abnormality that accompanies obesity and is a risk factor of type 2 diabetes. This review deals with this dual, seemingly contradictory, function of ROS and RNS in regulating insulin action: the major processes for ROS and RNS generation and detoxification are presented, and a critical review of the evidence that they participate in the positive and negative regulation of insulin action is provided. The cellular and molecular mechanisms by which ROS and RNS are thought to participate in normal insulin action and in the induction of insulin resistance are then described. Finally, we explore the potential usefulness and the challenges in modulating the oxidant-antioxidant balance as a potentially promising, but currently disappointing, means of improving insulin action in insulin resistance-associated conditions, leading causes of human morbidity and mortality of our era.
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Affiliation(s)
- Nava Bashan
- Department of Clinical Biochemistry, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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Papaconstantinou J. Insulin/IGF-1 and ROS signaling pathway cross-talk in aging and longevity determination. Mol Cell Endocrinol 2009; 299:89-100. [PMID: 19103250 PMCID: PMC2873688 DOI: 10.1016/j.mce.2008.11.025] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 11/11/2008] [Accepted: 11/12/2008] [Indexed: 01/29/2023]
Abstract
Regulation of hormonal, insulin/IGF-1 (Ins/IGF-1) signaling activities, and pathways of the intrinsic generation of reactive oxygen species (ROS) play a role in aging and longevity determination. In this review we discuss the cross-talk between these pathways as mechanisms of signaling that may be important factors in the regulation of aging and longevity. The balance of physiological processes controlling the rate of aging and longevity in several mouse mutants suggests the involvement of cross-talk mechanisms of regulation of the insulin/IGF1 signaling pathway vs. the ROS signaling pathways. In mice, modulation of the Ins/IGF-1 signaling pathways resulting from the Prop1(df), Pit1(dw) and Igf1 receptor mutations exemplify the hormonal pathways associated with aging and longevity determination. These pathways are also targets of the ROS-mediated redox pathways. Similarly, the Klotho and p66(Shc) mutants link regulation of ROS signaling pathways to aging and longevity determination. Both of these models also display altered insulin signaling activity, a characteristic associated with longevity. The Ins/IGF-1 signaling pathway is of particular interest because of its decreased activity due to genetic manipulation vs. its responsiveness to ROS levels.
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Affiliation(s)
- John Papaconstantinou
- Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, 301 University Blvd, Mail Route 0643, Galveston, TX 77555-0643, United States.
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Glutathione peroxidase 3 mediates the antioxidant effect of peroxisome proliferator-activated receptor gamma in human skeletal muscle cells. Mol Cell Biol 2008; 29:20-30. [PMID: 18936159 DOI: 10.1128/mcb.00544-08] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Oxidative stress plays an important role in the pathogenesis of insulin resistance and type 2 diabetes mellitus and in diabetic vascular complications. Thiazolidinediones (TZDs), a class of peroxisome proliferator-activated receptor gamma (PPARgamma) agonists, improve insulin sensitivity and are currently used for the treatment of type 2 diabetes mellitus. Here, we show that TZD prevents oxidative stress-induced insulin resistance in human skeletal muscle cells, as indicated by the increase in insulin-stimulated glucose uptake and insulin signaling. Importantly, TZD-mediated activation of PPARgamma induces gene expression of glutathione peroxidase 3 (GPx3), which reduces extracellular H(2)O(2) levels causing insulin resistance in skeletal muscle cells. Inhibition of GPx3 expression prevents the antioxidant effects of TZDs on insulin action in oxidative stress-induced insulin-resistant cells, suggesting that GPx3 is required for the regulation of PPARgamma-mediated antioxidant effects. Furthermore, reduced plasma GPx3 levels were found in patients with type 2 diabetes mellitus and in db/db/DIO mice. Collectively, these results suggest that the antioxidant effect of PPARgamma is exclusively mediated by GPx3 and further imply that GPx3 may be a therapeutic target for insulin resistance and diabetes mellitus.
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Tesauro M, Schinzari F, Rovella V, Melina D, Mores N, Barini A, Mettimano M, Lauro D, Iantorno M, Quon MJ, Cardillo C. Tumor necrosis factor-alpha antagonism improves vasodilation during hyperinsulinemia in metabolic syndrome. Diabetes Care 2008; 31:1439-41. [PMID: 18390795 PMCID: PMC2453644 DOI: 10.2337/dc08-0219] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Obesity is associated with chronic inflammation due to overproduction of proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha. We assessed the effects of TNF-alpha neutralization by infliximab on vascular reactivity during hyperinsulinemia in obesity-related metabolic syndrome. RESEARCH DESIGN AND METHODS Vascular responses to intra-arterial infusion of acetylcholine (ACh) and sodium nitroprusside (SNP) were assessed in patients with metabolic syndrome, before and after administration of infliximab. RESULTS Patients had blunted vasodilator responses to ACh and SNP during hyperinsulinemia compared with control subjects; a potentiation of the responsiveness to both ACh and SNP, however, was observed in patients following infliximab. The antioxidant vitamin C improved the vasodilator response to ACh in patients with metabolic syndrome, but its effect was not further enhanced by concurrent administration of infliximab. CONCLUSIONS TNF-alpha neutralization ameliorates vascular reactivity in metabolic syndrome during hyperinsulinemia, likely in relation to decreased oxidative stress, thereby suggesting an involvement of inflammatory cytokines in vascular dysfunction of these patients.
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Kim SH, Youm JH, Lee DK, Park SY, Shin CY, Ryu JS, La HO, Song HJ, Min YS, Sohn UD. Effect of hydrogen peroxide on VIP-induced relaxation of the cat lower esophageal sphincter. Arch Pharm Res 2008; 30:1419-25. [PMID: 18087810 DOI: 10.1007/bf02977366] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We investigated the effects of hydrogen peroxide (H2O2) on relaxation of the cat lower esophageal sphincter (LES). Vasoactive intestinal peptide (VIP) caused dose-dependent relaxation of LES, and H2O2 reduced VIP-induced relaxation. Relaxation was also attenuated by pertussis toxin (PTX), indicating a Gi/o component. VIP treatment increased [35S]GTPgammaS binding to Gs and Gi3 protein, but not to Go, Gq, Gil or Gi2. This increase in Gs or Gi3 binding was reduced by H2O2. However, the relaxation induced by sodium nitroprusside (SNP), 3-morpholino sydnomine (SIN-1), 8-br cGMP (cGMP analog), forskolin (adenylate cyclase activator), and dibutyryl-cAMP (a stable cAMP analog) was not reduced by H2O2. These data suggest that H202 inhibits VIP-induced relaxation via a Gi-dependent pathway, perhaps by inhibiting the activation of G(i3) or Gs downstream of the VIP receptor and independent of cAMP or NO-cGMP signaling.
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Affiliation(s)
- Sung Hyo Kim
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul 156-756, Korea
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Abstract
Glutathione peroxidase-1 (GPX1) represents the first identified mammalian selenoprotein, and our understanding in the metabolic regulation and function of this abundant selenoenzyme has greatly advanced during the past decade. Selenocysteine insertion sequence-associating factors, adenosine, and Abl and Arg tyrosine kinases are potent, Se-independent regulators of GPX1 gene, protein, and activity. Overwhelming evidences have been generated using the GPX1 knockout and transgenic mice for the in vivo protective role of GPX1 in coping with oxidative injury and death mediated by reactive oxygen species. However, GPX1 exerts an intriguing dual role in reactive nitrogen species (RNS)-related oxidative stress. Strikingly, knockout of GPX1 rendered mice resistant to toxicities of drugs including acetaminophen and kainic acid, known as RNS inducers. Intracellular and tissue levels of GPX1 activity affect apoptotic signaling pathway, protein kinase phosphorylation, and oxidant-mediated activation of NFkappaB. Data are accumulating to link alteration or abnormality of GPX1 expression to etiology of cancer, cardiovascular disease, neurodegeneration, autoimmune disease, and diabetes. Future research should focus on the mechanism of GPX1 in the pathogeneses and potential applications of GPX1 manipulation in the treatment of these disorders.
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Affiliation(s)
- Xin Gen Lei
- Department of Animal Science, Cornell University, Ithaca, NY 14853, USA.
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Clavreul N, Bachschmid MM, Hou X, Shi C, Idrizovic A, Ido Y, Pimentel D, Cohen RA. S-Glutathiolation of p21ras by Peroxynitrite Mediates Endothelial Insulin Resistance Caused by Oxidized Low-Density Lipoprotein. Arterioscler Thromb Vasc Biol 2006; 26:2454-61. [PMID: 16931794 DOI: 10.1161/01.atv.0000242791.28953.4c] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To understand the mechanism by which oxidants are linked to insulin resistance, bovine aortic endothelial cells were exposed to oxidized low-density lipoproteins (oxLDL) or peroxynitrite. METHODS AND RESULTS OxLDL transiently increased phosphorylation of Erk and Akt within 5 minutes, but 60 minutes later, resulted in decreased insulin-induced Akt phosphorylation. OxLDL promoted a 2- to 5-fold increase in oxidant generation as measured by dihydrorhodamine or dihydroethidium oxidation that was ascribed to peroxynitrite. Exogenous peroxynitrite (25 to 100 micromol/L) or oxidized glutathione mimicked the effects of oxLDL. OxLDL increased the S-glutathiolation of p21ras, and adenoviral transfection with either a mutant p21ras (C118S) lacking the predominant site of S-glutathiolation or a dominant-negative mutant restored insulin-induced Akt phosphorylation. The requirement for oxidant-mediated S-glutathiolation and activation of p21ras in mediating insulin resistance was further implicated by showing that insulin signaling was restored by Mek inhibitors or by overexpression of glutaredoxin-1. Furthermore, oxLDL increased Erk-dependent phosphorylation of insulin receptor substrate-1 serine-616 that was prevented by inhibiting oxidant generation, Erk activation, or by the p21ras C118S mutant. CONCLUSIONS This study provides direct evidence for a novel molecular mechanism by which oxidants can induce insulin resistance via S-glutathiolation of p21ras and Erk-dependent inhibition of insulin signaling.
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Affiliation(s)
- Nicolas Clavreul
- Director, Vascular Biology Unit, 650 Albany Street, X704, Boston, MA 02118.
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Carnesecchi S, Carpentier JL, Foti M, Szanto I. Insulin-induced vascular endothelial growth factor expression is mediated by the NADPH oxidase NOX3. Exp Cell Res 2006; 312:3413-24. [PMID: 16949073 DOI: 10.1016/j.yexcr.2006.07.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 06/24/2006] [Accepted: 07/14/2006] [Indexed: 11/24/2022]
Abstract
Vascular endothelial growth factor (VEGF) is the most potent stimulatory factor of angiogenesis. Its expression is induced by reactive oxygen species (ROS) in hypoxic conditions and by insulin in normoxic cells. Both ROS and insulin can activate mitogen-activated protein kinases (MAPKs) and induce the transcriptional factor Sp1, components that are essential for VEGF gene expression. The aim of this study was to investigate the role of ROS producing NADPH oxidase enzymes (NOX-es) in insulin-regulated VEGF gene activation. To achieve this goal we chose HepG2 cells as our model system as these cells express the NADPH oxidase isoform NOX3 and respond to insulin stimulation with enhanced ROS production and mRNA transcription and production of VEGF. We demonstrate that in control cells insulin stimulation leads to H2O2 generation, a biphasic activation of p42/44 MAPK and the induction of both Sp1 and HIF-1alpha. Transfection of NOX3-specific siRNA abrogates H2O2 production and inhibits exclusively the second phase of p42/44 MAPK phosphorylation and Sp1 DNA binding and thus prevents upregulation of VEGF-A mRNA expression. In conclusion, our results demonstrate that NOX3, a ROS generating NADPH oxidase, plays an integral role in insulin-induced p42/44 MAPK signal transmission and VEGF-A production.
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Affiliation(s)
- Stephanie Carnesecchi
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
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Jin D, Ryu SH, Kim HW, Yang EJ, Lim SJ, Ryang YS, Chung CH, Park SK, Lee KJ. Anti-diabetic effect of alkaline-reduced water on OLETF rats. Biosci Biotechnol Biochem 2006; 70:31-7. [PMID: 16428818 DOI: 10.1271/bbb.70.31] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alkalin-reduced water (ARW) is known to exert several anti-cancer effects, as well as to scavenge reactive oxygen species (ROS) and reduce blood-glucose levels. This study was performed in order to determine the effects of ARW on the control of spontaneous diabetes in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. We assigned 16 male OLETF rats (4 wk) to two groups: an experimental group, which was given ARW, and a control group, which received laboratory tap water. From week 6 to 32, the body weight, lipid composition, and glucose levels in the blood of the rats were measured. The glucose levels of both groups tended to increase. However, the ARW group's glucose levels were significantly lower than those of the control group after 12 weeks (p<0.05). The total cholesterol and triglyceride levels in the ARW group were found to be significantly lower than those of the control group during the experimental period. These results suggest that ARW spurred the growth of OLETF rats during the growth stage, and that long-term ingestion of ARW resulted in a reduction in the levels of glucose, triglycerides, and total cholesterol in the blood.
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Affiliation(s)
- Dan Jin
- Department of Microbiology, Wonju College of Medicine, Yonsei University, Korea
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Tabet F, Schiffrin EL, Touyz RM. Mitogen-activated protein kinase activation by hydrogen peroxide is mediated through tyrosine kinase-dependent, protein kinase C-independent pathways in vascular smooth muscle cells: upregulation in spontaneously hypertensive rats. J Hypertens 2006; 23:2005-12. [PMID: 16208142 DOI: 10.1097/01.hjh.0000185715.60788.1b] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To investigate the putative molecular mechanisms underlying mitogen-activated protein (MAP) kinase activation by hydrogen peroxide (H(2)O(2)) in vascular smooth muscle cells (VSMC) and to evaluate whether H(2)O(2)-induced actions are altered in VSMC from spontaneously hypertensive rats (SHR). METHOD VSMC from mesenteric arteries of Wistar-Kyoto rats (WKY) and SHR were stimulated with H(2)O(2) (2-30 min). The phosphorylation of extracellular signal-regulated kinases (ERK)1/2 and p38MAP kinase was determined by immunoblotting. The involvement of tyrosine kinase and protein kinase C (PKC) was evaluated using pharmacological inhibitors, tyrphostin (A23 and A9) and GF109203X, respectively. The role of receptor tyrosine kinases (RTK) was assessed with AG1478, AG1296 and AG1024, selective inhibitors of epidermal growth factor receptor, platelet-derived growth factor receptor and insulin-like growth factor receptor, respectively. Non-receptor tyrosine kinases (NRTK) were studied using AG490 (JAK2 inhibitor) and PP2 (Src inhibitor). RESULTS H(2)O(2) stimulated phosphorylation of ERK1/2 and p38MAP kinase in a time-dependent manner. This increase was significantly greater in SHR versus WKY (P < 0.01). The activation of MAP kinases was unaffected by GF109203X but was decreased by tyrphostins (P < 0.01). The inhibition of NRTK attenuated H(2)O(2)-mediated phosphorylation of ERK1/2 (P < 0.001) but not of p38MAP kinase, whereas Src and JAK2 inhibition significantly decreased phosphorylation of both MAP kinases (P < 0.01). CONCLUSION These data indicate that H(2)O(2) increases ERK1/2 and p38MAP kinase activation through tyrosine kinase-dependent, PKC-independent mechanisms. Whereas ERK1/2 is regulated by both RTK and NRTK, p38MAP kinase is regulated by NRTK. Our findings identify an important role for tyrosine kinases, but not PKC, in H(2)O(2)-induced phosphorylation of ERK1/2 and p38MAP kinase in VSMC. The upregulation of these processes may contribute to enhanced redox-dependent MAP kinase signaling in SHR VSMC.
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MESH Headings
- Animals
- Enzyme Activation/drug effects
- ErbB Receptors/metabolism
- Hydrogen Peroxide/pharmacology
- Janus Kinase 2
- Male
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3/metabolism
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Oxidants/pharmacology
- Phosphorylation/drug effects
- Protein Kinase C/metabolism
- Protein Kinases/metabolism
- Protein-Tyrosine Kinases/metabolism
- Proto-Oncogene Proteins/metabolism
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Receptors, Platelet-Derived Growth Factor/metabolism
- Receptors, Somatomedin/metabolism
- Signal Transduction/drug effects
- Up-Regulation/drug effects
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Affiliation(s)
- Fatiha Tabet
- Multidisciplinary Research Group on Hypertension, Clinical Research Institute of Montreal, University of Montreal, Quebec, Canada
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45
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Abstract
Reactive oxygen and nitrogen species (ROS and RNS) recently emerged as critical signaling molecules in cardiovascular research. Several studies over the past decade have shown that physiological effects of vasoactive factors are mediated by these reactive species and, conversely, that altered redox mechanisms are implicated in the occurrence of metabolic and cardiovascular diseases. Oxidant stress occurs when ROS and/or RNS production exceeds the cell natural antioxidant systems, and pathological events ensue. Cardiovascular risk factors are associated with an imbalance of the redox equilibrium toward oxidative stress, leading to endothelial activation and proinflammatory processes implicated in atherogenesis and metabolic disorders. Recent studies indicate that insulin and insulin-sensitizing drugs activate antiinflammatory pathways that may limit oxidant stress in insulin target tissues. The main goal of this brief review is to discuss recent progress in the field of cellular redox signaling as it pertains to insulin modulation of vascular endothelial function in cardiovascular diseases.
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Affiliation(s)
- Raymond Christon
- Lipides Membranaires et Fonctions Cardiovasculaires, UMR INRA-Université Paris XI, Faculté de Pharmacie, Châtenay-Malabry
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46
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Dröge W. Oxidative enhancement of insulin receptor signaling: experimental findings and clinical implications. Antioxid Redox Signal 2005; 7:1071-7. [PMID: 15998262 DOI: 10.1089/ars.2005.7.1071] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Signaling through the insulin receptor and several other receptor tyrosine kinases is subject to redox regulation. Prolonged exposure to hydrogen peroxide impairs the action of insulin, and may account to some extent for the decreased insulin responsiveness in hyperglycemic diabetic patients. However, insulin receptor kinase (IRK) autophosphorylation and/or kinase activity were found to be markedly enhanced by a more limited exposure to hydrogen peroxide or by an oxidative shift in the thiol/disulfide redox status. Oxidative enhancement of IRK function may be mediated by two different mechanisms with similar effects, i.e., by direct oxidative activation of IRK activity or by oxidative inactivation of a protein tyrosine phosphatase, which otherwise down-regulates IRK-mediated signaling. As both mechanisms enhance IRK activity in the absence of insulin, there is a strong possibility that the background IRK activity in the postabsorptive period may be abnormally increased in certain oxidative conditions and thereby disturb the metabolism of glucose and other energy substrates. This remains to be tested. In line with the oxidative enhancement of IRK activity, clinical studies have shown that treatment with a thiol-containing antioxidant increases the postabsorptive glucose and/or insulin concentrations (i.e., the HOMA-R index) at least under certain conditions. This effect may have therapeutic implications.
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Affiliation(s)
- Wulf Dröge
- Tumor Immunology Program, Deutsches Krebsforschungszentrum, Heidelberg, Germany.
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Abstract
Reactive oxygen and nitrogen molecules have been typically viewed as the toxic by-products of metabolism. However, accumulating evidence has revealed that reactive species, including hydrogen peroxide, serve as signaling molecules that are involved in the regulation of cellular function. The chronic and/or increased production of these reactive molecules or a reduced capacity for their elimination, termed oxidative stress, can lead to abnormal changes in intracellular signaling and result in chronic inflammation and insulin resistance. Inflammation and oxidative stress have been linked to insulin resistance in vivo. Recent studies have found that this association is not restricted to insulin resistance in type 2 diabetes, but is also evident in obese, nondiabetic individuals, and in those patients with the metabolic syndrome. An increased concentration of reactive molecules triggers the activation of serine/threonine kinase cascades such as c-Jun N-terminal kinase, nuclear factor-kappaB, and others that in turn phosphorylate multiple targets, including the insulin receptor and the insulin receptor substrate (IRS) proteins. Increased serine phosphorylation of IRS reduces its ability to undergo tyrosine phosphorylation and may accelerate the degradation of IRS-1, offering an attractive explanation for the molecular basis of oxidative stress-induced insulin resistance. Consistent with this idea, studies with antioxidants such as vitamin E, alpha-lipoic acid, and N-acetylcysteine indicate a beneficial impact on insulin sensitivity, and offer the possibility for new treatment approaches for insulin resistance.
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Affiliation(s)
- Joseph L Evans
- Medical Research Institute, San Francisco, CA 94107, USA.
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Frank GD, Eguchi S, Motley ED. The role of reactive oxygen species in insulin signaling in the vasculature. Antioxid Redox Signal 2005; 7:1053-61. [PMID: 15998260 DOI: 10.1089/ars.2005.7.1053] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Although there is an abundance of evidence suggesting that insulin resistance plays a significant role in the vasculature, the precise mechanistic role involved still remains unclear. In this review, we discuss the current background of insulin resistance in the context of insulin signaling and action in the vasculature. Also, studies suggest that insulin resistance, diabetes, and cardiovascular disease all share a common involvement with oxidative stress. Recently, we reported that lysophosphatidylcholine, a major bioactive product of oxidized low-density lipoprotein, and angiotensin II, a vasoactive hormone and a potent inducer of reactive oxygen species (ROS), negatively regulate insulin signaling in vascular smooth muscle cells (VSMCs). In endothelial cells, insulin stimulates the release of nitric oxide, which results in VSMC relaxation and inhibition of atherosclerosis. Other data suggest that angiotensin II inhibits the vasodilator effects of insulin through insulin receptor substrate-1 phosphorylation at Ser312 and Ser616. Moreover, ROS impair insulin-induced vasorelaxation by neutralizing nitric oxide to form peroxynitrite. Thus, evidence is growing to enable us to better understand mechanistically the relationship between insulin/insulin resistance and ROS in the vasculature, and the impact they have on cardiovascular disease.
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Affiliation(s)
- Gerald D Frank
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
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Affiliation(s)
- Ashok K Srivastava
- Laboratory of Cell Signaling, Research Centre, Centre hospitalier de l'Université de Montréal (CHUM)-Hôtel-Dieu and Department of Medicine, Université de Montréal, Montreal, Quebec, Canada
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Taniyama Y, Hitomi H, Shah A, Alexander RW, Griendling KK. Mechanisms of Reactive Oxygen Species–Dependent Downregulation of Insulin Receptor Substrate-1 by Angiotensin II. Arterioscler Thromb Vasc Biol 2005; 25:1142-7. [PMID: 15802620 DOI: 10.1161/01.atv.0000164313.17167.df] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
Angiotensin II has been implicated in the pathogenesis of the vascular complications of insulin resistance. Recently, serine phosphorylation and degradation of insulin receptor substrate-1 (IRS-1) were shown to inhibit Akt activation and reduce glucose uptake. Therefore, we examined the effects of chronic angiotensin II treatment on IRS-1 phosphorylation and protein expression in vascular smooth muscle cells (VSMCs).
Methods and Results—
Using Western analysis, we found that angiotensin II (100 nmol/L; 18 hours) caused a 61±5% degradation of IRS-1 and abolished insulin-induced activation of Akt. Phosphorylation of IRS-1 on Ser307, which leads to subsequent IRS-1 degradation, was stimulated by angiotensin II. This phosphorylation was blocked by the Src inhibitor PP1 and by the antioxidants
N
-acetylcysteine and ebselen. Stable overexpression of catalase abrogated angiotensin II–induced IRS-1 phosphorylation and IRS-1 degradation. Similarly, a mutant phosphoinositide-dependent kinase-1 (PDK1) that cannot associate with Src abolished IRS-1 phosphorylation and degradation induced by angiotensin II. Proteasome inhibitors also prevented IRS-1 degradation.
Conclusions—
Thus, angiotensin II decreases IRS-1 protein levels in VSMCs via Src, PDK1, and reactive oxygen species–mediated phosphorylation of IRS-1 on Ser307 and subsequent proteasome-dependent degradation. These events impair insulin signaling and provide a molecular basis for understanding the clinical observation that angiotensin II type 1 receptor antagonists improve insulin resistance and its associated vasculopathies.
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Affiliation(s)
- Yoshihiro Taniyama
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Ga 30322, USA
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