Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30044 (antioxidant enzyme)
8,037 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We previously showed that during protoplast isolation, an oxidative burst occurred and the generation of active oxygen species was differentially mediated in tobacco (Nicotiana tabacum) and grapevine (Vitis vinifera), accompanied by significant quantitative differences (A.K. Papadakis, K.A. Roubelakis-Angelakis [1999] Plant Physiol 127: 197-205). We have now further tested if the expression of totipotency in protoplasts is related to the activity of cellular antioxidant machinery during protoplast culture. Totipotent (T) tobacco protoplasts had 2-fold lower contents of intracellular O2*- and H2O2 and 7-fold lower levels of O2*- and H2O2 in the culture medium, compared with non-totipotent (NT) tobacco protoplasts. Addition of alkaline dimethylsulfoxide, known to generate O2*-, resulted in isolation of tobacco protoplasts with reduced viability and cell division potential during subsequent culture. Active oxygen species levels decreased in tobacco and grapevine protoplasts during culturing, although higher contents of O2*- and H2O2 were still found in NT- compared with T-tobacco protoplasts, after 8 d in culture. In T-tobacco protoplasts, the reduced forms of ascorbate and glutathione predominated, whereas in NT-tobacco and grapevine protoplasts, the oxidized forms predominated. In addition, T-tobacco protoplasts exhibited severalfold lower lipid peroxidation than NT-tobacco and grapevine protoplasts. Furthermore, several antioxidant enzyme activities were increased in T-tobacco protoplasts. Superoxide dismutase activity increased in tobacco, but not in grapevine protoplasts during culturing due to the increased expression of cytoplasmic Cu/Zn-superoxide dismutase. The increase was only sustained in T-tobacco protoplasts for d 8. Together, these results suggest that suppressed expression of totipotency in protoplasts is correlated with reduced activity of the cellular antioxidant machinery.
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PMID:Reduced activity of antioxidant machinery is correlated with suppression of totipotency in plant protoplasts. 1135 Nov 5

The main components of antioxidant enzyme system (AOS) are superoxide dismutase (SOD) and glutathione reductase (GR) catalyses the conversion of the superoxide anion. The important role in AOS belongs to catalase and glutathione peroxidase which perform H2O2 to nontoxic products. Simultaneous determination of AOS activity and malonic dialdehide (MDA) concentration (the index of lipid peroxidation in tissues and blood) characterize cells complex resistance to damage factor. The effect of L-arginine, as a precursor of nitric oxide synthesis and blocator NO-synthase (Nw-nitro-L-arginine) on AOS of rats with different resistance to hypoxia under stress condition is unknown and were subject of our investigation. Experiments were done on liver and blood tissues of white laboratory rats. The experimental animals were divided on two groups depending on hypoxia factor: high resistance (HR) and low resistance (LR). The type of resistance was determined by the time of ability to respire in barocamera with oxygen deficient equal to 12.000 meters over sea level. The animals adaptation to laboratory conditions continue during 14 days after in barocamera presence. All animals were divided dependent on experiment conditions on fourth groups. The first group: intact (HR and LR) animals parentherally injected by 1 ml of 0.9% NaCl solution. The second group was subject of stress condition. The third group: HR and LR animals injected parentherally by 1 ml L-arginine (Sigma, USA) dose (600 mg/kg body weight). The fourth one: rats injected by 1 ml Nw-nitro-L-arginine (L-NNA, Sigma, USA)--the blocator of NO-synthase. The animals were decapitated 30 min after injection and stress condition under ethereal anesthesia. Activity of antioxidant system enzymes superoxide dismutase (SOD), catalase (CAT); glutathione reductase (GR), glutathione peroxidase (GP) were measured spectrophotometrically. Also was investigated the concentration of serum antioxidant ceruloplasmin (CP). Level of lipid peroxidation was estimate by examination of concentration of lipids of hydroperoxides (LHP) and malonic dialdehyde (MDA). Our data confirm suggesting that nitric oxide (NO) is a major regulator in the AOS enzymes activity and limit damage influence of AOF. Action precursor NO L-arginine might be capable of protective role in various disorders which are connected with hypoxia factor. Following thing can be interred the investigation of influence of nitric oxide adaptive answers in stress condition modelling of pathological processes in rats with different resistance to hypoxia and reflect the biological qualities data stady on AOZ and LP.
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PMID:[Effect of nitric oxide synthase inhibitor L-NNA on the activities of antioxidant enzymes and lipid peroxidation in blood and tissues of rats with different resistance to hypoxia]. 1139 15

Respiratory function of mitochondria is compromised in aging human tissues and severely impaired in the patients with mitochondrial disease. A wide spectrum of mitochondrial DNA (mtDNA) mutations has been established to associate with mitochondrial diseases. Some of these mtDNA mutations also occur in various human tissues in an age-dependent manner. These mtDNA mutations cause defects in the respiratory chain due to impairment of the gene expression and structure of respiratory chain polypeptides that are encoded by the mitochondrial genome. Since defective mitochondria generate more reactive oxygen species (ROS) such as O2- and H2O2 via electron leak, we hypothesized that oxidative stress is a contributory factor for aging and mitochondrial disease. This hypothesis has been supported by the findings that oxidative stress and oxidative damage in tissues and culture cells are increased in elderly subjects and patients with mitochondrial diseases. Another line of supporting evidence is our recent finding that the enzyme activities of Cu,Zn-SOD, catalase and glutathione peroxidase (GPx) decrease with age in skin fibroblasts. By contrast, Mn-SOD activity increases up to 65 years of age and then slightly declines thereafter. On the other hand, we observed that the RNA, protein and activity levels of Mn-SOD are increased two- to three-fold in skin fibroblasts of the patients with CPEO syndrome but are dramatically decreased in patients with MELAS or MERRF syndrome. However, the other antioxidant enzymes did not change in the same manner. The imbalance in the expression of these antioxidant enzymes indicates that the production of ROS is in excess of their removal, which in turn may elicit an elevation of oxidative stress in the fibroblasts. Indeed, it was found that intracellular levels of H2O2 and oxidative damage to DNA and lipids in skin fibroblasts from elderly subjects or patients with mitochondrial diseases are significantly increased as compared to those of age-matched controls. Furthermore, Mn-SOD or GPx-1 gene knockout mice were found to display neurological disorders and enhanced oxidative damage similar to those observed in the patients with mitochondrial disease. These observations are reviewed in this article to support that oxidative stress elicited by defective respiratory function and impaired antioxidant enzyme system plays a key role in the pathophysiology of mitochondrial disease and human aging.
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PMID:Oxidative stress in human aging and mitochondrial disease-consequences of defective mitochondrial respiration and impaired antioxidant enzyme system. 1140 14

Oxidative stress has been causally linked to a variety of neurodegenerative diseases. To clarify the role of the antioxidant enzyme (AOE) system in oxidative brain damage primary cultures of rat astroglial cells were exposed to hydrogen peroxide (H2O2). Expression of AOEs and several parameters for cell viability and functionality were measured. In our experiments astrocytes responded to low concentrations of H2O2 exposure with a pronounced generation of ROS which ran parallel with induction of lipid peroxidation. This distinct oxidative stress was not reflected in cell viability or functionality parameters measured. Cytotoxicity, a decrease in glutathione content of astrocytes, and impairment of mitochondrial functions became obvious only for higher concentrations of H2O2. After H2O2 exposure catalase, manganese superoxide dismutase, and glutathione peroxidase expression levels were found to be increased, whereas copper/zinc superoxide dismutase mRNA expression was not affected. These data indicate that the AOE system of astrocytes can be directly regulated by oxidative stress and may thus contribute to protection of cells against oxidative insults.
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PMID:Changes in antioxidant enzyme expression in response to hydrogen peroxide in rat astroglial cells. 1140 37

Catalase is an important antioxidant enzyme that detoxifies H2O2 into oxygen and water and thus limits the deleterious effects of reactive oxygen species (ROS). Because chronic exposure to excess ROS may contribute to vascular damage, we investigated whether genetic variation in catalase was associated with susceptibility to essential hypertension (EHYT) in 324 individuals (at least 50 years old) who were randomly sampled from an isolated population living in Xiangchang, China. They were screened for genetic variation in the promoter of catalase by direct sequencing. In total, four single nucleotide polymorphisms (SNPs) were identified. The association between the SNPs and EHYT was investigated by a linear regression model under phenotypic selection; in our analyses, we used both SBP>150 mmHg and SBP>160 mmHg as thresholds. A SNP 844 bp upstream of the start codon (SNP-844) demonstrated strong evidence of association with EHYT (SBP>150 mmHg: F=5.09, P=0.008; SBP>160 mmHg: F=7.13, P=0.002). This is the first study to implicate genetic variation in catalase in susceptibility to EHYT and suggests that polymorphisms in promoter regions may be particularly relevant to the study of complex diseases.
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PMID:A polymorphism in the promoter region of catalase is associated with blood pressure levels. 1147 40

The comparative effects of fish oil given by gavage and fish oil enriched diet on metabolism and function of lymphocytes and macrophages were investigated. For this purpose, the following parameters were examined: 1) phagocytosis capacity, production of superoxide (O2*-) and hydrogen peroxide (H2O2) by macrophages, 2) lymphocytes proliferation capacity, 3) antioxidant enzyme activities in the mesenteric lymph nodes (MEN) and liver, 4) Thiobarbituric Acid Reactive Substances (TBARS) content in MLN, liver, and plasma, 5) total antioxidant capacity of the plasma, and 6) fatty acid composition of macrophages, MLN, liver and plasma. Both FO treatments did not affect phagocytosis capacity but increased hydrogen peroxide production by macrophages in the presence of PMA. FO given by gavage markedly increased lymphocytes proliferation both in the absence (5.8-fold) and in the presence (16.7-fold) of Con A, whereas FO-rich diet showed an increase in the presence of Con A only (53.3%). FO given by gavage raised the proliferation index by 2.9-fold and FO-rich diet increased by 29% only as compared to controls. Concomitantly, FO given by gavage was more effective to increase TBARS content in plasma. The proportion of some fatty acids in the tissues and cells was also differently changed depending on the way FO was administered to rats: in particular: myristic, arachidonic, and eicosapentaenoic acids. This fact may partially explain the differences between both FO treatments.
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PMID:Comparative effects of fish oil given by gavage and fish oil-enriched diet on leukocytes. 1166 36

The consumption of a cholesterol-enriched diet increases the degree of lipid peroxidation, which is one of the early processes of atherosclerosis. The aim of this trial was to determine the antioxidative effects of the citrus bioflavonoid, naringin, a potent cholesterol-lowering agent, compared to the cholesterol-lowering drug, lovastatin, in rabbits fed a high cholesterol diet. Male rabbits were served a high-cholesterol (0.5%, w/w) diet or high-cholesterol diet supplemented with either naringin (0.5% cholesterol, 0.05% naringin, w/w) or lovastatin (0.5% cholesterol, 0.03% lovastatin, w/w) for 8 weeks to determine the plasma and hepatic lipid peroxide, plasma vitamin A and E levels, and hepatic hydrogen peroxide levels, along with the hepatic antioxidant enzyme activities and gene expressions. Only the lovastatin group showed significantly lower plasma and hepatic lipid peroxide levels compared to the control group. The naringin supplementation significantly increased the activities of both hepatic SOD and catalase by 33% and 20%, respectively, whereas the lovastatin supplementation only increased the catalase activity by 23% compared to control group. There was no difference in the GSH-Px activities between the various groups. Content of H2O2 in hepatic mitochondria was significantly lower in groups supplemented with lovastatin and naringin than in control group. However, there was no difference in cytosolic H2O2 content in liver between groups. The concentration of plasma vitamin E was significantly increased by the naringin supplementation. When comparing the antioxidant enzyme gene expression, the mRNA expression of SOD, catalase and GSH-Px was significantly up-regulated in the naringin-supplemented group. Accordingly, these results would appear to indicate that naringin, a citrus bioflavonoid, plays an important role in regulating antioxidative capacities by increasing the SOD and catalase activities, up-regulating the gene expressions of SOD, catalase, and GSH-Px, and protecting the plasma vitamin E. In contrast, lovastatin exhibited an inhibitory effect on the plasma and hepatic lipid peroxidation and increased the hepatic catalase activity in high-cholesterol fed rabbits.
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PMID:Antioxidative activity of naringin and lovastatin in high cholesterol-fed rabbits. 1172 89

Hydrogen peroxide (H(2)O(2)) is present in the atmosphere at concentrations known to induce cell and tissue damage. However, inhaled H(2)O(2) vapor should not reach the lower lung due to its high water solubility. It has been suggested that hygroscopic components of particulate matter (PM) may transport H(2)O(2) into the lower lung and induce tissue injury and this was investigated. Ammonium sulfate [(NH(4))(2)SO(4)] was selected as a model for fine atmospheric PM. Treatment of female Sprague-Dawley rats with (NH(4))(2)SO(4) (429 or 215 microg/m(3); 0.3-0.4 microm mass median diameter) or H(2)O(2) (10, 20, or 100 ppb) alone or in combination for 2 h had no major effect on bronchoalveolar lavage fluid cell number or viability or on protein content or lactate dehydrogenase levels, either immediately or 24 h after exposure, relative to air-exposed rats. However, electron microscopy revealed increased numbers of neutrophils in pulmonary capillaries adhered to the vascular endothelium in rats treated with the combination of (NH(4))(2)SO(4) + H(2)O(2). Exposure of rats to (NH(4))(2)SO(4) + H(2)O(2) also resulted in tumor necrosis factor-alpha (TNF-alpha) production by alveolar macrophages. This was observed immediately and 24 h after exposure. Immediately after inhalation of (NH(4))(2)SO(4) + H(2)O(2), a transient increase in production of superoxide anion by alveolar macrophages was observed. In contrast, nitric oxide production by cells from rats exposed to (NH(4))(2)SO(4) + H(2)O(2) or H(2)O(2) alone was decreased, and this persisted for 24 h. Decreases in nitric oxide may be due to superoxide anion-driven formation of peroxynitrite. In this regard, nitrotyrosine, an in vivo marker of peroxynitrite, was detected in lung tissue after exposure of rats to (NH(4))(2)SO(4) + H(2)O(2) or H(2)O(2). We also found that expression of the antioxidant enzyme heme oxygenase-1 by stimulated alveolar macrophages was increased following exposure of rats to (NH(4))(2)SO(4) + H(2)O(2). Taken together, these studies demonstrate that the biological effects of inhaled fine PM are augmented by H(2)O(2). Moreover, tissue injury induced by fine PM may be related to altered production of cytotoxic mediators by alveolar macrophages.
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PMID:Tissue injury following inhalation of fine particulate matter and hydrogen peroxide is associated with altered production of inflammatory mediators and antioxidants by alveolar macrophages. 1174 18

There is increasing evidence for the generation of reactive oxygen species in skin upon ultraviolet exposure, but little is known about their pathophysiologic relevance in human skin in vivo. We hypothesized that chronic and acute photodamage is mediated by depleted antioxidant enzyme expression and increased oxidative protein modifications. Biopsies from patients with histologically confirmed solar elastosis, from non-ultraviolet-exposed sites of age-matched controls, and from young subjects were analyzed. To evaluate the influence of acute ultraviolet exposures, buttock skin of 12 healthy subjects was irradiated repetitively on 10 d with a solar simulator and compared intraindividually to non-ultraviolet-treated contralateral sites. The antioxidant enzymes catalase, copper-zinc superoxide dismutase, and manganese superoxide dismutase were investigated by immunohistochemistry. Protein carbonyls were analyzed by immunohistochemical and immunoblotting techniques in human skin and in cell models. Whereas overall expression of antioxidant enzymes was very high in the epidermis, low baseline levels were found in the dermis. In photoaged skin, a significant depletion of antioxidant enzyme expression was observed within the stratum corneum and in the epidermis. Importantly, an accumulation of oxidatively modified proteins was found specifically within the upper dermis of photoaged skin. Upon acute ultraviolet exposure of healthy subjects, depleted catalase expression and increased protein oxidation were detected. Exposures of keratinocytes and fibroblasts to ultraviolet B, ultraviolet A, and H2O2 led to dose-dependent protein oxidation and thus confirmed in vivo results. In conclusion, the correlation between photodamage and protein oxidation was demonstrated for the first time, which hence may be a relevant pathophysiologic factor in photoaging.
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PMID:Photoaging is associated with protein oxidation in human skin in vivo. 1191 7

The aims of our study were to assess whether the increased oxidative stress in inflamed joints is reflected by serum lipid peroxidation and also to check alterations in the levels of extracellular antioxidants and antioxidant enzyme activities in patients with rheumatoid arthritis. Serum malondialdehyde and ceruloplasmin levels and the activity of CuZn superoxide dismutase were higher, while transferrin levels and the activities of glutathione peroxidase and catalase were lower in patients (n = 37) than in healthy controls (n = 30). Disease activity score correlated positively with serum malondialdehyde level and CuZn superoxide dismutase activity. Probably, superoxide radicals in serum could be dismutated to produce hydrogen peroxide by increased CuZn superoxide dismutase activity, but hydrogen peroxide could not have been detoxified due to decreased activities of serum glutathione peroxidase and catalase. Hydrogen peroxide possibly converted to hydroxyl radical by iron due to lower transferrin level might have led to increased serum lipid peroxidation in patients with rheumatoid arthritis.
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PMID:Lipid peroxidation, some extracellular antioxidants, and antioxidant enzymes in serum of patients with rheumatoid arthritis. 1195 37


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