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)

Human fibroblasts (HFW) were 10-fold more susceptible than Chinese hamster ovary (CHO-K1) cells to sodium arsenite. Comparison of cellular antioxidant enzyme activities showed that CHO-K1 cells contained 3- and 8-fold more glutathione-peroxidase and catalase activities, respectively, than HFW cells. Since vitamin E, methylamine, and benzyl alcohol could prevent, in part, the arsenite-induced killing of HFW cells, we suggest that arsenite can induce oxidative damage in HFW cells. We have also established arsenic-resistant cells, SA7 and CL3R, from CHO cells and from a human lung adenocarcinoma cell line (CL3), respectively. The arsenic resistance of SA7 cells was attributed mainly to elevation of glutathione S-transferase pi levels, and that of CL3R cells was possibly due to an increase in heme oxygenase activity. Since induction of heme oxygenase is a general response to oxidative stress, we suspect that the differential toxicity of arsenic to human and animal cells could be due to arsenic's more efficient induction of oxidative damage in human cells.
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PMID:Differential cytotoxic effects of arsenic on human and animal cells. 784 80

The apparent anticarcinogenic effect of cruciferous vegetables found in numerous epidemiological and experimental studies has been associated with their influence on phase I and phase II metabolising enzymes as well as on the antioxidant status. In the present study we investigated the effect of administration of a Brussels sprouts extract on the expression at the mRNA level and/or catalytic activity in rat liver of three phase I enzymes [cytochrome P450-1A2 (CYP1A2),-2B1/2 (CYP2B1/2) and-2E1 (CYP2E1)] and two phase II enzyme [NADPH:quinone reductase (QR) and glutathione S-transferase pi 7 (GSTpi)], all previously suggested to be induced by vegetables. We also examined the activity and/or expression of several important antioxidant enzymes: glutathione peroxidase (GPx), catalase and gamma-glutamyl-cysteine synthetase (GCS) and the activity of the repair enzyme 8-oxoguanine DNA glycosylase (OGG1). QR, GPx and catalase activity was also assessed in the kidneys. In order to examine a possible effect of the Brussels sprouts related to oxidative stress, we measured oxidative DNA damage in terms of 7-hydro-8-oxo-2'-deoxyguanosine (8-oxodG) and lipid peroxidation in terms of malondialdehyde (MDA) formation in the liver. Oral administration of an aqueous Brussels sprouts extract for 4 days was found to induce the expression of GST 1.3-fold (P < 0.05) and the activity of QR 2.6-fold in rat liver (P < 0.05). No significant differences were seen in the expression of the phase I enzymes. No differences in antioxidant enzyme activity/expression or OGG1 activity were observed. In a second experiment, administration of the Brussels sprouts extract for 3 or 7 days was found to increase the level of 8-oxodG in rat liver from 0.75 to 0.97 per 10(5) dG and from 0.81 to 0.97 per 10(5) dG, respectively (P < 0.05). No effects on MDA levels were found. The present results support the data obtained in several studies that consumption of cruciferous vegetables is capable of inducing various phase II enzyme systems. However, the observed increase in oxidative DNA damage raises the question of whether greatly increased ingestion of cruciferous vegetables is beneficial.
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PMID:Effects of a Brussels sprouts extract on oxidative DNA damage and metabolising enzymes in rat liver. 1134 82