UNIPROT:P30044 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Target Concepts:

Query: UNIPROT:P30044 (antioxidant enzyme)
8,037 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thioredoxin reductase (TrxR) is one of a number of flavoproteins that catalyze the transfer of electrons between pyridine nucleotides and a specific disulfide-containing substrate. Thioredoxin reductase from Streptomyces aureofaciens 3239 has been purified to homogeneity by a two-step chromatographic procedure including anion-exchange chromatography and affinity chromatography on 2'5'-ADP-Sepharose 4B. Molar mass determined by chromatography on Superose 12 HR 10/30 and sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed 69 kDa for the native protein and 34.8 kDa for the enzyme subunit. The isoelectric point determined by isoelectric focusing gel electrophoresis was 4.3. TrxR effectively catalyzed the reduction of DTNB in the presence of S. aureofaciens thioredoxin-1. TrxR activity in the presence of S. aureofaciens thioredoxin-2 was only 1/4 of the activity with thioredoxin-1 (1). The activity of pure TrxR decreased drastically in the presence of NADPH, while NADP+ as well as Streptomyces aureofaciens thioredoxin-1 protected the enzyme from inactivation. These results indicate that thioredoxin reductase activity in bacteria could be modulated by the redox status of NADP+/NADPH and thioredoxin pools.
...
PMID:Purification and partial characterization of thioredoxin reductase from Streptomyces aureofaciens. 984 25

The experimental study carried out with white rats Wistar trend, which were introduced of sodium nitrate at a rate of 9.6 g/kg of their mass. It follows to the development of considerable activation of lipid peroxidation and depression of antioxidant system in liver. The obtained results permit supposing the significant role of nitric oxide (NO) in liver as a factor resulting in accumulation of peroxidation products. The research has stated that the use hyperbaric oxygenation (HBO) prevents considerable activation of lipid peroxidation and the decrease of antioxidant enzyme (catalase and superoxide dismutase) activity. The results permit supposing that the effect HBO is connected with the decrease of the rate of reduction of nitrate-ions to NO.
...
PMID:[Effect of hyperbaric oxygenation of lipid peroxidation and the antioxidant system in liver of white rats with acute sodium nitrate poisoning]. 984 87

Protective effects of sodium tanshinone IIA sulphonate against adriamycin-induced lipid peroxidation were investigated. Data showed that treatment with sodium tanshinone IIA sulphonate could prevent mice from decrease in body weight caused by adriamycin. It was found that myocardial lipid peroxidation in sodium tanshinone IIA sulphonate-treated mice was lower compared with that in adriamycin-treated ones. The activities of some endogenous antioxidant enzymes, such as superoxide dismutase, glutathione peroxidase and catalase, were higher in the sodium tanshinone IIA sulphonate group than that in the adriamycin group. In vitro experiments showed that sodium tanshinone IIA sulphonate could inhibit adriamycin-induced mitochondrial lipid peroxidation and swelling. Sodium tanshinone IIA sulphonate could scavenge adriamycin semiquinone free radical in heart homogenate dose-dependently. Thus, protective effects of sodium tanshinone IIA sulphonate may not only be related to its antioxidant activity but also to its regulation of antioxidant enzyme activities in the heart.
...
PMID:Protective effects of sodium tanshinone IIA sulphonate against adriamycin-induced lipid peroxidation in mice hearts in vivo and in vitro. 1066 Sep 46

Three terrestrial plant species, oat (Avena sativa ), Chinese cabbage (Brassica campestris cv. chinensis) and lettuce (Lactuca sativa), were exposed to different concentrations of herbicide TCA (sodium trichloroacetate) in a growth test according to guideline OECD # 208. Classical (i.e. germination and biomass) and biochemical (i.e., antioxydant enzyme activities) endpoints were investigated. Germination rate decreased significantly at 3.9 mg TCA kg dry soil(-1) (for oat and lettuce) and 62.5 mg TCA kg dry soil(-1) (for Chinese cabbage). Biomass decreased significantly only at 1.9 mg TCA kg dry soil(-1) (for oat and lettuce) and 15.6 mg TCA kg dry soil(-1) (for Chinese cabbage). The activities of superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), peroxidase (EC 1.11.1.7) and glutathione reductase (EC 1.6.4.2) increased significantly at the lowest concentration of TCA tested, i.e. 0.03 mg TCA kg dry soil(-1) (for oat and lettuce) and 0.48 mg TCA kg dry soil(-1) (for Chinese cabbage). Our results showed a ranking of sensitivity among the different endpoints for the three plant species: enzyme activities>biomass>germination rate. The increase in antioxidant enzyme activities observed in this study ensured the detoxification of increased levels of active oxygen species, and presumably prevented the plants from undergoing oxidative stress damage. Thus, the use of enzyme activities will permit the detection of early injury in plant growth testing.
...
PMID:Classical and biochemical endpoints in the evaluation of phytotoxic effects caused by the herbicide trichloroacetate. 1106 42

Estrogens exert profound effects on the physiology of diverse target cells and these effects appear to be mediated by two estrogen receptor (ER) subtypes, ERalpha and ERbeta. We have investigated how ER ligands, ranging from pure agonists to antagonists, interact with ERalpha and ERbeta, and regulate their transcriptional activity on different genes. Mutational mapping-structure activity studies indicate that different residues of the ER ligand binding domain are involved in the recognition of structurally distinct estrogens and antiestrogens. We have identified from ligands of diverse structure, several particularly interesting ones that are high potency selective agonists via ERalpha and others that are full agonists through ERalpha while being full antagonists through ERbeta. Antiestrogens such as hydroxytamoxifen, which are mixed agonist/antagonists through ERalpha, are pure antagonists through ERbeta at estrogen response element-containing gene sites. Studies with ERalpha/beta chimeric proteins reveal that tamoxifen agonism requires the activation function 1 region of ERalpha. Through two-hybrid assays, we have isolated an ER-specific coregulator that potentiates antiestrogen antagonist effectiveness and represses ER transcriptional activity. We have also focused on understanding the distinct pharmacologies of antiestrogen- and estrogen-regulated genes. Although antiestrogens are thought to largely act by antagonizing the actions of estrogens, we have found among several new ER-regulated genes, quinone reductase (QR), a detoxifying phase II antioxidant enzyme, that has its activity up-regulated by antiestrogens in an ER-dependent manner in breast cancer cells. This response is antagonized by estrogens, thus showing 'reversed pharmacology'. Increased QR activity by antiestrogens requires a functional ER (ERalpha or ERbeta) and is, interestingly, mediated via the electrophile response element in the QR gene 5' regulatory region. The up-regulation of QR may contribute to the beneficial effects of tamoxifen, raloxifene, and other antiestrogens in breast cancer prevention and treatment. Estrogens rapidly up-regulate expression of several genes associated with cell cytoarchitectural changes including NHE-RF, the sodium hydrogen exchanger regulatory factor, also known as EBP50. NHE-RF/EBP50 is enriched in microvilli, and may serve as a scaffold adaptor protein in regulating early changes in cell architecture and signal transduction events induced by estrogen. Analyses of the regulatory regions of these primary response genes, and the antioxidant and other signaling pathways involved, are providing considerable insight into the mechanisms by which ligands, that function as selective estrogen receptor modulators or SERMs, exert their marked effects on the activities and properties of target cells. The intriguing biology of estrogens in its diverse target cells is thus determined by the structure of the ligand, the ER subtype involved, the nature of the hormone-responsive gene promoter, and the character and balance of coactivators and corepressors that modulate the cellular response to the ER-ligand complex. The continuing development of ligands that function as selective estrogens or antiestrogens for ERalpha or ERbeta should allow optimized tissue selectivity of these agents for menopausal hormone replacement therapy and the treatment and prevention of breast cancer.
...
PMID:Molecular mechanisms of estrogen action: selective ligands and receptor pharmacology. 1116 36

Nitric oxide (*NO) and its by-products modulate many physiological functions of skeletal muscle including blood flow, metabolism, glucose uptake, and contractile function. However, growing evidence suggests that an overproduction of nitric oxide contributes to muscle wasting in a number of pathologies including chronic heart failure, sepsis, COPD, muscular dystrophy, and extreme disuse. Limited data point to the potential of inhibition various enzymes by reactive nitrogen species (RNS), including (.)NO and its downstream products such as peroxynitrite, primarily in purified systems. We hypothesized that exposure of skeletal muscle to RNS donors would reduce or downregulate activities of the crucial antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX). Diaphragm muscle fiber bundles were extracted from 4-month-old Fischer-344 rats and, in a series of experiments, exposed to either (a) 0 (control), 1, or 5 mM diethylamine NONOate (DEANO: *NO donor); (b) 0, 100, 500 microM, or 1 mM sodium nitroprusside (SNP: *NO donor); (c) 0 or 2 mM S-nitroso-acetylpenicillamine (SNAP: *NO donor); or (d) 0 or 500 microM SIN-1 (peroxynitrite donor) for 60 min. DEANO resulted in a 50% reduction in CAT, GPX, and a dose-dependent inhibition of Cu, Zn-SOD. SNP resulted in significantly lower activities for total SOD, Mn-SOD isoform, Cu, Zn-SOD isoform, CAT, and GPX in a dose-dependent fashion. Two millimolar SNAP and 500 microM SIN-1 also resulted in a large and significant inhibition of total SOD and CAT. These data indicate that reactive nitrogen species impair antioxidant enzyme function in an RNS donor-specific and dose-dependent manner and are consistent with the hypothesis that excess RNS production contributes to skeletal muscle oxidative stress and muscle dysfunction.
...
PMID:Specificity of antioxidant enzyme inhibition in skeletal muscle to reactive nitrogen species donors. 1207 89

Mutations in Cu/Zn superoxide dismutase (SOD1), a major cytosolic antioxidant enzyme in eukaryotic cells, have been reported in approximately 20% of familial amyotrophic lateral sclerosis (FALS) patients. Hereditary canine spinal muscular atrophy (HCSMA), a fatal inherited motor neuron disease in Brittany spaniels, shares many clinical and pathological features with human motor neuron disease, including FALS. The SOD1 coding region has been sequenced and cloned from several animal species, but not from the dog. We have mapped the chromosomal location, sequenced, and characterized the canine SOD1 gene. Extending this analysis, we have evaluated SOD1 as a candidate for HCSMA. The 462 bp SOD1 coding region in the dog encodes 153 amino acid residues and exhibits more than 83% and 79% sequence identity to other mammalian homologues at both the nucleotide and amino acid levels, respectively. The canine SOD1 gene maps to CFA31 close to syntenic group 13 on the radiation hybrid (RH) map in the vicinity of sodium myo/inositol transporter (SMIT) gene. The human orthologous SOD1 and SMIT genes have been localized on HSA 21q22.1 and HSA 21q21, respectively, confirming the conservation of synteny between dog syntenic group 13 and HSA 21. Direct sequencing of SOD1 cDNA from six dogs with HCSMA revealed no mutations. Northern analysis indicated no differences in steady-state levels of SOD1 mRNA.
...
PMID:Structure, chromosomal location, and analysis of the canine Cu/Zn superoxide dismutase (SOD1) gene. 1214 Feb 71

The inhibitory effects of isoflavones (genistin, daidzin and their aglycones genistein, daidzein) on sodium nitroprusside (SNP; nitric oxide donor)- or peroxynitrite-mediated DNA damage in intact cells and in plasmid DNA was investigated. RAW 264.7 cells, a murine macrophage cell line, are capable of producing nitric oxide and superoxide anion. However, macrophages themselves are also shown to be more sensitive to nitric oxide or peroxynitrite, and were therefore used in these studies. Results from single-cell gel electrophoresis (the comet assay) showed that these isoflavones, at the concerning of 25-200 microM, inhibited the induction of nitric oxide- or peroxynitrite-mediated macrophage genotoxicity, with genistein showing the greatest inhibition. Genistein and daidzein, at a concentration of 1-25 microm, dose-dependently inhibited peroxynitrite-induced phiX174 DNA degradation based on the results of agarose gel electrophoretic analysis. Although SNP could increase the cellular GSH level, no significant differences in the glutathione content or the GSH:GSSG ratio were observed for genistein and daidzein in the presence or absence of SNP as compared with SNP-only treated RAW 264.7 cells. Exposure of RAW 264.7 cells to SNP caused the enzyme activities of GSH peroxidase, GSH reductase and catalase decrease to 44, 20 and 34% of that of untreated cells, respectively. On the contrary, exposure of RAW 264.7 cells to SNP in the presence of 100 microm of genistein or daidzein caused the enzyme activities of GSH peroxidase, GSH reductase and catalase decrease to 18, 9 and 12% (genistein) or 13, 9 and 19% (daidzein) of that of untreated cells, respectively. These results suggest that the inhibition by isoflavones of SNP- or peroxynitrite- mediated DNA damage could be attributed to their nitric oxide or peroxynitrite scavenging activities and their prevention of antioxidant enzyme inactivation.
...
PMID:Inhibitory effects of isoflavones on nitric oxide- or peroxynitrite-mediated DNA damage in RAW 264.7 cells and phiX174 DNA. 1238 5

We attempted to determine the level and form of selenium (Se) that yielded the maximum Se status of yeast cells, for their evaluation as a source of Se for chemopreventive action. The influence of various Se concentrations from organic (selenomethionine) and inorganic (sodium selenite) Se compounds on growth pattern and cell viability and the alterations in the antioxidant enzyme system of yeast were evaluated. A continuous decrease in cell and colony-forming units counts was observed with increasing concentrations of Se from either source. Increasing Se status of yeast cells was found with increasing concentrations of Se with both forms, with much greater uptake for organic Se at maximum Se concentrations. A continuous increase in glutathione peroxidase (GSH-Px) activity with increasing Se concentrations in both forms revealed an active Se response in terms of antioxidant activity, with a more pronounced percentage increase with selenomethionine. A highly significant increase in total glutathione was observed with selenomethionine supplementation, compared with sodium selenite. A decreasing trend in reduced glutathione was observed with increasing organic or inorganic Se concentrations. An increasing trend in glutathione-S-transferase activity was observed with increasing Se concentrations for both forms. Significantly higher values of glutathione-S-transferase were associated with the organic form at higher Se concentrations. There was normal activity of Se in mammalian cells. The results showed that an organic Se source more greatly enhances the Se status of yeast cells and hence could help in chemoprevention if consumed by the population.
...
PMID:Growth characteristics and selenium status changes of yeast cells with inorganic and organic selenium supplementation: selenium, a chemopreventive agent. 1248 55

The neuropathology of Parkinson's disease (PD) involves a reduction of endogenous antioxidant enzyme systems, heightened oxidative stress and mitochondrial aberrations in the region of the substantia nigra. Similarly, neurotoxins commonly used to investigate PD pathology include 6-hydroxydopamine (6-OHDA), a powerful hydrogen peroxide (H(2)0(2)) pro-oxidant and 1-methyl-4-phenylpyridinium ion (MPP+), a mitochondrial complex I inhibitor that exerts detrimental effects on cellular energy production. Pyruvic acid is a neuronal metabolic energy fuel that can also rapidly undergo decarboxylation to diffuse H(2)0(2) into H(2)0. In this study, we investigated the effect of pyruvic acid against 6-OHDA, MPP+ and H(2)0(2) toxicity in murine brain neuroblastoma cells. The results obtained indicated that the toxicity of 6-OHDA was inversely related to the autoxidative formation of H(2)0(2). Pyruvic acid exhibited powerful non-enzymatic stoichiometric H(2)0(2) trapping properties, and protected against both 6-OHDA and H(2)0(2) toxicity. While both sodium pyruvate and pyruvate were highly protective against oxidative stress, pyruvate in its free acid form only was protective against MPP+, indicating a requirement for effective transport in order to fuel glycolysis. The protective properties of glucose were compared to pyruvic acid, and the data indicated that glucose did not exhibit antioxidant properties and was effective in blocking MPP+, but not 6-OHDA or H(2)0(2) toxicity. On the other hand, pyruvic acid was protective against all three toxins, and unlike glucose, completely blocked MPP+ toxicity in a combination insult model with up to 500 microM of H(2)0(2). Moreover, the data obtained indicate that pyruvic acid exerts powerful neuroprotective properties by providing simultaneous resistance to oxidative stress and mitochondrial insult. These protective effects are the result of a unique dual property of pyruvic acid with concurrent ability to serve as an effective neuronal energy substrate for glycolysis and to act as an exceptionally powerful antioxidant.
...
PMID:Pyruvic acid cytoprotection against 1-methyl-4-phenylpyridinium, 6-hydroxydopamine and hydrogen peroxide toxicities in vitro. 1252 92

<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>