Nitric Oxide, Oxidative Stress, andp66ShcInterplay in Diabetic Endothelial Dysfunction

Increased oxidative stress and reduced nitric oxide (NO) bioavailability play a causal role in endothelial cell dysfunction occurring in the vasculature of diabetic patients. In this review, we summarized the molecular mechanisms underpinning diabetic endothelial and vascular dysfunction. In particular, we focused our attention on the complex interplay existing among NO, reactive oxygen species (ROS), and one crucial regulator of intracellular ROS production,p66Shcprotein.

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Organic Nitrates and Nitrate Resistance in Diabetes: The Role of Vascular Dysfunction and Oxidative Stress with Emphasis on Antioxidant Properties of Pentaerithrityl Tetranitrate

Experimental Diabetes Research ◽

10.1155/2010/213176 ◽

2010 ◽

Vol 2010 ◽

pp. 1-13 ◽

Cited By ~ 17

Author(s):

Matthias Oelze ◽

Swenja Schuhmacher ◽

Andreas Daiber

Keyword(s):

Oxidative Stress ◽

Diabetes Mellitus ◽

Vascular Dysfunction ◽

Antioxidant Properties ◽

Nitrate Tolerance ◽

Diabetic Patients ◽

Organic Nitrates ◽

Common Principle ◽

No Bioavailability

Organic nitrates represent a class of drugs which are clinically used for treatment of ischemic symptoms of angina as well as for congestive heart failure based on the idea to overcome the impaired NO bioavailability by “NO” replacement therapy. The present paper is focused on parallels between diabetes mellitus and nitrate tolerance, and aims to discuss the mechanisms underlying nitrate resistance in the setting of diabetes. Since oxidative stress was identified as an important factor in the development of tolerance to organic nitrates, but also represents a hallmark of diabetic complications, this may represent a common principle for both disorders where therapeutic intervention should start. This paper examines the evidence supporting the hypothesis that pentaerithrityl tetranitrate may represent a nitrate for treatment of ischemia in diabetic patients. This evidence is based on the considerations of parallels between diabetes mellitus and nitrate tolerance as well as on preliminary data from experimental diabetes studies.

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Healthberry 865® and Its Related, Specific, Single Anthocyanins Exert a Direct Vascular Action, Modulating Both Endothelial Function and Oxidative Stress

Antioxidants ◽

10.3390/antiox10081191 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1191

Author(s):

Albino Carrizzo ◽

Rosario Lizio ◽

Paola Di Pietro ◽

Michele Ciccarelli ◽

Antonio Damato ◽

...

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Nadph Oxidase ◽

Intracellular Signaling ◽

Vascular Reactivity ◽

Molecular Mechanisms ◽

Vascular Dysfunction ◽

Epidemiological Studies ◽

Direct Role ◽

And Oxidative Stress

In recent years, epidemiological studies have identified a relationship between diet and cerebro–cardiovascular disease (CVD). In this regard, there is a promising dietary group for cardiovascular protection are polyphenols, especially anthocyanins. Vascular reactivity studies were performed using Healthberry 865® and constituent single anthocyanins to characterize vasomotor responses; immunofluorescence analysis with dichlorofluorescein diacetate and dihydroethidium were used to evaluate nitric oxide and oxidative stress; lucigenin assay was used to measure NADPH oxidase activity; and gel electrophoresis and immunoblotting were used to dissect the molecular mechanisms involved. We demonstrated that Healthberry 865® exerts an important vasorelaxant effect of resistance artery functions in mice. Its action is mediated by nitric oxide release through the intracellular signaling PI3K/Akt. Moreover, behind its capability of modulating vascular tone, it also exerts an important antioxidant effect though the modulation of the NADPH oxidase enzyme. Interestingly, its cardiovascular properties are mediated by the selective action of different anthocyanins. Finally, the exposure of human dysfunctional vessels to Healthberry 865® significantly reduces oxidative stress and improves NO bioavailability. Although further investigations are needed, our data demonstrate the direct role of Healthberry 865® on the modulation of vasculature, both on the vasorelaxation and on oxidative stress; thus, supporting the concept that a pure mixture of anthocyanins could be helpful in preventing the onset of vascular dysfunction associated with the development of CVD.

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Pathological and Pharmacological Roles of Mitochondrial Reactive Oxygen Species in Malignant Neoplasms: Therapies Involving Chemical Compounds, Natural Products, and Photosensitizers

Molecules ◽

10.3390/molecules25225252 ◽

2020 ◽

Vol 25 (22) ◽

pp. 5252

Author(s):

Yasuyoshi Miyata ◽

Yuta Mukae ◽

Junki Harada ◽

Tsuyoshi Matsuda ◽

Kensuke Mitsunari ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Molecular Mechanisms ◽

Malignant Tumors ◽

Reactive Oxygen ◽

Chemotherapeutic Agents ◽

Malignant Neoplasms ◽

Oxygen Species ◽

Efficient Treatment ◽

Intracellular Ros

Oxidative stress plays an important role in cellular processes. Consequently, oxidative stress also affects etiology, progression, and response to therapeutics in various pathological conditions including malignant tumors. Oxidative stress and associated outcomes are often brought about by excessive generation of reactive oxygen species (ROS). Accumulation of ROS occurs due to dysregulation of homeostasis in an otherwise strictly controlled physiological condition. In fact, intracellular ROS levels are closely associated with the pathological status and outcome of numerous diseases. Notably, mitochondria are recognized as the critical regulator and primary source of ROS. Damage to mitochondria increases mitochondrial ROS (mROS) production, which leads to an increased level of total intracellular ROS. However, intracellular ROS level may not always reflect mROS levels, as ROS is not only produced by mitochondria but also by other organelles such as endoplasmic reticulum and peroxisomes. Thus, an evaluation of mROS would help us to recognize the biological and pathological characteristics and predictive markers of malignant tumors and develop efficient treatment strategies. In this review, we describe the pathological significance of mROS in malignant neoplasms. In particular, we show the association of mROS-related signaling in the molecular mechanisms of chemically synthesized and natural chemotherapeutic agents and photodynamic therapy.

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Regulation of reactive oxygen species by p53: implications for nitric oxide-mediated apoptosis

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00535.2009 ◽

2010 ◽

Vol 298 (6) ◽

pp. H2192-H2200 ◽

Cited By ~ 33

Author(s):

Daniel A. Popowich ◽

Ashley K. Vavra ◽

Christopher P. Walsh ◽

Hussein A. Bhikhapurwala ◽

Nicholas B. Rossi ◽

...

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Reactive Oxygen Species ◽

Reactive Oxygen ◽

Cell Types ◽

Oxygen Species ◽

Antioxidant Protein ◽

Intracellular Ros ◽

Stressed Cells ◽

Induced Apoptosis

Nitric oxide (NO) induces vascular smooth muscle cell (VSMC) apoptosis in part through activation of p53. Traditionally, p53 has been thought of as the gatekeeper, determining if a cell should undergo arrest and repair or apoptosis following exposure to DNA-damaging agents, depending on the severity of the damage. However, our laboratory previously demonstrated that NO induces apoptosis to a much greater extent in p53−/− compared with p53+/+ VSMC. Increased reactive oxygen species (ROS) within VSMC has been shown to induce VSMC apoptosis, and recently it was found that the absence of, or lack of, functional p53 leads to increased ROS and oxidative stress within different cell types. This study investigated the differences in intracellular ROS levels between p53−/− and p53+/+ VSMC and examined if these differences were responsible for the increased susceptibility to NO-induced apoptosis observed in p53−/− VSMC. We found that p53 actually protects VSMC from NO-induced apoptosis by increasing antioxidant protein expression [i.e., peroxiredoxin-3 (PRx-3)], thereby reducing ROS levels and cellular oxidative stress. We also observed that the NO-induced apoptosis in p53−/− VSMC was largely abrogated by pretreatment with catalase. Furthermore, when the antioxidant protein PRx-3 and its specific electron acceptor thioredoxin-2 were silenced within p53+/+ VSMC with small-interfering RNA, not only did these cells exhibit greater ROS production, but they also exhibited increased NO-induced apoptosis similar to that observed in p53−/− VSMC. These findings suggest that ROS mediate NO-induced VSMC apoptosis and that p53 protects VSMC from NO-induced apoptosis by decreasing intracellular ROS. This research demonstrates that p53 has antioxidant functions in stressed cells and also suggests that p53 has antiapoptotic properties.

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Effect of Shuangdan Mingmu capsule, a Chinese herbal formula, on oxidative stress-induced apoptosis of pericytes through PARP/GAPDH pathway

BMC Complementary Medicine and Therapies ◽

10.1186/s12906-021-03238-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Fujiao Nie ◽

Jiazhao Yan ◽

Yanjun Ling ◽

Zhengrong Liu ◽

Chaojun Fu ◽

...

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Oxidative Damage ◽

Damage Model ◽

B Cell Lymphoma ◽

Cell Counting ◽

Network Pharmacology ◽

Diabetic Patients ◽

Induced Apoptosis

Abstract Background Diabetic retinopathy (DR) has become a worldwide concern because of the rising prevalence rate of diabetes mellitus (DM). Despite much energy has been committed to DR research, it remains a difficulty for diabetic patients all over the world. Since apoptosis of retinal microvascular pericytes (RMPs) is the early characteristic of DR, this study aimed to reveal the mechanism of Shuangdan Mingmu (SDMM) capsule, a Chinese patent medicine, on oxidative stress-induced apoptosis of pericytes implicated with poly (ADP-ribose) polymerase (PARP) / glyceraldehyde 3-phosphate dehydrogenase (GAPDH) pathway. Methods Network pharmacology approach was performed to predict biofunction of components of SDMM capsule dissolved in plasma on DR. Both PARP1 and GAPDH were found involved in the hub network of protein-protein interaction (PPI) of potential targets and were found to take part in many bioprocesses, including responding to the regulation of reactive oxygen species (ROS) metabolic process, apoptotic signaling pathway, and response to oxygen levels through enrichment analysis. Therefore, in vitro research was carried out to validate the prediction. Human RMPs cultured with media containing 0.5 mM hydrogen oxide (H2O2) for 4 h was performed as an oxidative-damage model. Different concentrations of SDMM capsule, PARP1 inhibitor, PARP1 activation, and GAPDH inhibitor were used to intervene the oxidative-damage model with N-Acetyl-L-cysteine (NAC) as a contrast. Flow cytometry was performed to determine the apoptosis rate of cells and the expression of ROS. Cell counting kit 8 (CCK8) was used to determine the activity of pericytes. Moreover, nitric oxide (NO) concentration of cells supernatant and expression of endothelial nitric oxide synthase (eNOS), superoxide dismutase (SOD), B cell lymphoma 2 (BCL2), vascular endothelial growth factor (VEGF), endothelin 1 (ET1), PARP1, and GAPDH were tested through RT-qPCR, western blot (WB), or immunocytochemistry (ICC). Results Overproduction of ROS, high apoptotic rate, and attenuated activity of pericytes were observed after cells were incubated with media containing 0.5 mM H2O2. Moreover, downregulation of SOD, NO, BCL2, and GAPDH, and upregulation of VEGFA, ET1, and PARP1 were discovered after cells were exposed to 0.5 mM H2O2 in this study, which could be improved by PARP1 inhibitor and SDMM capsule in a dose-dependent way, whereas worsened by PARP1 activation and GAPDH inhibitor. Conclusions SDMM capsule may attenuate oxidative stress-induced apoptosis of pericytes through downregulating PARP expression and upregulating GAPDH expression.

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Age-Related Macular Degeneration: Role of Oxidative Stress and Blood Vessels

International Journal of Molecular Sciences ◽

10.3390/ijms22031296 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1296

Author(s):

Yue Ruan ◽

Subao Jiang ◽

Adrian Gericke

Keyword(s):

Oxidative Stress ◽

Macular Degeneration ◽

Vascular Function ◽

Vascular Dysfunction ◽

Therapeutic Strategies ◽

Vision Impairment ◽

Age Related Macular Degeneration ◽

Oxygen Species ◽

Age Related

Age-related macular degeneration (AMD) is a common irreversible ocular disease characterized by vision impairment among older people. Many risk factors are related to AMD and interact with each other in its pathogenesis. Notably, oxidative stress and choroidal vascular dysfunction were suggested to be critically involved in AMD pathogenesis. In this review, we give an overview on the factors contributing to the pathophysiology of this multifactorial disease and discuss the role of reactive oxygen species and vascular function in more detail. Moreover, we give an overview on therapeutic strategies for patients suffering from AMD.

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Vitamin E-Coated Dialyzer Inhibits Oxidative Stress

Blood Purification ◽

10.1159/000478971 ◽

2017 ◽

Vol 44 (4) ◽

pp. 288-293 ◽

Cited By ~ 4

Author(s):

Shiho Yamadera ◽

Yuya Nakamura ◽

Masahiro Inagaki ◽

Isao Ohsawa ◽

Hiromichi Gotoh ◽

...

Keyword(s):

Oxidative Stress ◽

Vitamin E ◽

Synthetic Polymer ◽

Intracellular Reactive Oxygen Species ◽

Ros Production ◽

Oxygen Species ◽

In Vitro Methods ◽

Stress Effects ◽

Intracellular Ros

Aim: To examine the effects of vitamin E-coated dialyzer on oxidative stress in vitro. Methods: A dialyzer with a synthetic polymer membrane (APS-11SA) and vitamin E-coated dialyzer (VPS-11SA) were connected to a blood tubing line, and U937 cells were circulated in the device. The circulating fluid was collected at 1, 2, 5, 10, 25, and 50 cycles, which are estimated numbers of passes through the dialyzer. Intracellular reactive oxygen species (ROS) production, malondialdehyde (MDA), and Cu/Zn-superoxide dismutase (SOD) were quantified. Results: Intracellular ROS production was increased in the first cycle by APS-11SA and was decreased throughout the experiment by VPS-11SA. Intracellular ROS production in the VPS-11SA device was lower, and MDA levels were decreased. MDA levels were lower during VPS-11SA processing than during APS-11SA processing. Cu/Zn-SOD levels remained unchanged. Conclusion: Our results highlight anti-oxidative-stress effects of a vitamin E-coated dialyzer.

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The role of oxidative/nitrosative stress in pathogenesis of paracetamol-induced toxic hepatitis

Medicinski pregled ◽

10.2298/mpns1012827r ◽

2010 ◽

Vol 63 (11-12) ◽

pp. 827-832 ◽

Cited By ~ 7

Author(s):

Tatjana Radosavljevic ◽

Dusan Mladenovic ◽

Danijela Vucevic ◽

Rada Jesic-Vukicevic

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Reactive Oxygen Species ◽

Liver Injury ◽

Kupffer Cells ◽

Reactive Oxygen ◽

Oxygen Species ◽

Severe Liver ◽

Hepatocellular Necrosis

Introduction. Paracetamol is an effective analgesic/antipyretic drug when used at therapeutic doses. However, the overdose of paracetamol can cause severe liver injury and liver necrosis. The mechanism of paracetamol-induced liver injury is still not completely understood. Reactive metabolite formation, depletion of glutathione and alkylation of proteins are the triggers of inhibition of mitochondrial respiration, adenosine triphosphate depletion and mitochondrial oxidant stress leading to hepatocellular necrosis. Role of oxidative stress in paracetamol-induced liver injury. The importance of oxidative stress in paracetamol hepatotoxicity is controversial. Paracetamol induced liver injury cause the formation of reactive oxygen species. The potent sources of reactive oxygen are mitochondria, neutrophils, Kupffer cells and the enzyme xatnine oxidase. Free radicals lead to lipid peroxidation, enzymatic inactivation and protein oxidation. Role of mitochondria in paracetamol-induced oxidative stress. The production of mitochondrial reactive oxygen species is increased, and the glutathione content is decreased in paracetamol overdose. Oxidative stress in mitochondria leads to mito?chondrial dysfunction with adenosine triphosphate depletion, increase mitochondrial permeability transition, deoxyribonu?cleic acid fragmentation which contribute to the development of hepatocellular necrosis in the liver after paracetamol overdose. Role of Kupffer cells in paracetamol-induced liver injury. Paracetamol activates Kupffer cells, which then release numerous cytokines and signalling molecules, including nitric oxide and superoxide. Kupffer cells are important in peroxynitrite formation. On the other hand, the activated Kupffer cells release anti-inflammatory cytokines. Role of neutrophils in paracetamol-induced liver injury. Paracetamol-induced liver injury leads to the accumulation of neutrophils, which release lysosomal enzymes and generate superoxide anion radicals through the enzyme nicotinamide adenine dinucleotide phosphate oxidase. Hydrogen peroxide, which is influenced by the neutrophil-derived enzyme myeloperoxidase, generates hypochlorus acid as a potent oxidant. Role of peroxynitrite in paracetamol-induced oxidative stress. Superoxide can react with nitric oxide to form peroxynitrite, as a potent oxidant. Nitrotyrosine is formed by the reaction of tyrosine with peroxynitrite in paracetamol hepatotoxicity. Conclusion. Overdose of paracetamol may produce severe liver injury with hepatocellular necrosis. The most important mechanisms of cell injury are metabolic activation of paracetamol, glutathione depletion, alkylation of proteins, especially mitochondrial proteins, and formation of reactive oxygen/nitrogen species.

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Abstract 316: Effects of Inhibiting of Inducible Nitric Oxide Synthase in the Pathophysiology of Experimental Preeclampsia

Hypertension ◽

10.1161/hyp.60.suppl_1.a316 ◽

2012 ◽

Vol 60 (suppl_1) ◽

Author(s):

Lorena M Amaral ◽

Ana Carolina T Palei ◽

Lucas C Pinheiro ◽

Jonas T Sertorio ◽

Danielle A Guimaraes ◽

...

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Reactive Oxygen Species ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Inducible Nitric Oxide Synthase ◽

Inos Expression ◽

Oxygen Species ◽

Oxide Synthase ◽

Inducible Nitric Oxide

The pathophysiology of preeclampsia (PE) is not entirely known. However, increased oxidative stress possibly leading to impaired nitric oxide activity has been implicated in the critical condition. Increased oxidative stress with increased levels of highly reactive species including superoxide may generate peroxynitrite. We examined the role of inducible nitric oxide synthase (iNOS) and oxidative stress in the reduced uterine perfusion pressure (RUPP) preeclampsia experimental model. METHODS: RUPP was induced in wistar rats. Pregnant rats in the RUPP group had their aortic artery clipped at day 14 of gestation. After a midline incision, a silver clip (0.203 mm) was placed around the aorta above the iliac bifurcation; silver clips (0.100 mm) were also placed on branches of both the right and left ovarian arteries that supply the uterus. Sham-operated (pregnant control rats) and RUPP rats were treated with oral vehicle or 1 mg/kg/day 1400W (iNOS inhibitor) for 5 days. Mean arterial pressure (MAP) and plasma levels of thiobarbituric acid-reactive species (TBARS) and total radical-trapping antioxidant potential (TRAP) were measured determined. Aortic iNOS expression (Western blotting) and reactive oxygen species (ROS; assessed by fluorescence microscopy with dihydroethidium-DHE) were measured. We found increased mean arterial pressure in RUPP compared with pregnant control rats (MAP= 128±1 vs. 100±1.8 mmHg, respectively; P<0.05) and 1400W exerted antihypertensive effects (MAP= 114±2 vs.128±1 mmHg in RUPP treated and untreated rats, respectively; P<0.05). Higher reactive oxygen species (ROS) concentrations were found in RUPP compared with pregnant control rats (7.1±0.5 vs. 5.1±0.5 arbitrary units (A.U.), respectively; P<0.05) and 1400W decreased ROS production to 5.8±0.02 A.U. in RUPP treated rats, P<0.05. In addition, 1400W attenuated iNOS expression in RUPP rats (0.29±0.02 vs. 0.55±0.8 A.U. in RUPP treated and untreated rats, respectively; P<0.01) and had no effects on plasma TBARS and TRAP levels. Our results suggest that 1400w exerts antihypertensive effects in the RUPP model and suppresses ROS formation. Supported by FAPESP,Cnpq.

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Effect of extracellular Mg2+ on ROS and Ca2+ accumulation during reoxygenation of rat cardiomyocytes

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.280.1.h344 ◽

2001 ◽

Vol 280 (1) ◽

pp. H344-H353 ◽

Cited By ~ 27

Author(s):

Mohammad N. Sharikabad ◽

Kirsten M. Østbye ◽

Torstein Lyberg ◽

Odd Brørs

Keyword(s):

Nitric Oxide ◽

Reactive Oxygen Species ◽

Flow Cytometry ◽

Lactate Dehydrogenase ◽

Superoxide Anion ◽

Oxygen Species ◽

No Donor ◽

Rat Cardiomyocytes ◽

Intracellular Ros ◽

Ldh Release

The effects of Mg2+ on reactive oxygen species (ROS) and cell Ca2+ during reoxygenation of hypoxic rat cardiomyocytes were studied. Oxidation of 2′,7′-dichlorodihydrofluorescein (DCDHF) to dichlorofluorescein (DCF) and of dihydroethidium (DHE) to ethidium (ETH) within cells were used as markers for intracellular ROS levels and were determined by flow cytometry. DCDHF/DCF is sensitive to H2O2 and nitric oxide (NO), and DHE/ETH is sensitive to the superoxide anion (O2 −·), respectively. Rapidly exchangeable cell Ca2+ was determined by 45Ca2+uptake. Cells were exposed to hypoxia for 1 h and reoxygenation for 2 h. ROS levels, determined as DCF fluorescence, were increased 100–130% during reoxygenation alone and further increased 60% by increasing extracellular Mg2+concentration to 5 mM at reoxygenation. ROS levels, measured as ETH fluorescence, were increased 16–24% during reoxygenation but were not affected by Mg2+. Cell Ca2+ increased three- to fourfold during reoxygenation. This increase was reduced 40% by 5 mM Mg2+, 57% by 10 μM 3,4-dichlorobenzamil (DCB) (inhibitor of Na+/Ca2+ exchange), and 75% by combining Mg2+ and DCB. H2O2 (25 and 500 μM) reduced Ca2+ accumulation by 38 and 43%, respectively, whereas the NO donor S-nitroso- N-acetyl-penicillamine (1 mM) had no effect. Mg2+ reduced hypoxia/reoxygenation-induced lactate dehydrogenase (LDH) release by 90%. In conclusion, elevation of extracellular Mg2+ to 5 mM increased the fluorescence of the H2O2/NO-sensitive probe DCF without increasing that of the O2 −·-sensitive probe ETH, reduced Ca2+ accumulation, and decreased LDH release during reoxygenation of hypoxic cardiomyocytes. The reduction in LDH release, reflecting the protective effect of Mg2+, may be linked to the effect of Mg2+ on Ca2+ accumulation and/or ROS levels.

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