Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Effects of antioxidants, reactive oxygen species (ROS) scavengers, and Ca2+ on cisplatin-induced renal cell injury were studied in rabbit renal cortical slices in vitro. Cisplatin induced LDH release and lipid peroxidation, inhibition of PAH uptake, and GSH depletion. These changes were significantly prevented by thiols (DTT and GSH), antioxidants (DPPD and BHA), and an iron chelator (deferoxamine). Superoxide dismutase partially reduced the cisplatin-induced LDH release without affecting the lipid peroxidation and the GSH depletion. Catalase did not affect the LDH release and the lipid peroxidation induced by cisplatin. Hydroxyl radical scavengers prevented the lipid peroxidation, whereas they did not alter the LDH release, the inhibition of PAH uptake, and the GSH depletion induced by cisplatin. Removal of Ca2+ or addition of EGTA to the incubation medium did not alter cisplatin effects on LDH release and lipid peroxidation. Buffering intracellular Ca2+ with quin-2/AM or inhibition of intracellular Ca2+ release with TMB-8 significantly reduced the cisplatin effect on LDH release without any effect on the lipid peroxidation and the GSH depletion. Ruthenium red attenuated the LDH release, the lipid peroxidation, and the inhibition of PAH uptake mediated by cisplatin. La3+ prevented the cisplatin effect on the LDH release, whereas it did not affect the lipid peroxidation, the inhibition of PAH uptake, and the GSH depletion by cisplatin. These results suggest that cisplatin induces a lethal cell injury by lipid peroxidation-dependent and -independent mechanisms and that the cell injury and the lipid peroxidation by cisplatin are iron-dependent. In addition, the data indicate that the Ca2+ released from intracellular stores, but not the Ca2+ moved from extracellular space, plays a role in the cisplatin-induced cell injury independent of lipid peroxidation.
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PMID:Effects of antioxidants and Ca2+ in cisplatin-induced cell injury in rabbit renal cortical slices. 934 94

BACKGROUND: DT diaphorase (DTD; NAD(P)H:quinone oxidoreductase; EC 1.6.99.2) catalyses the two electron reduction of quinones, thus preventing redox cycling and consequently quinone dependent production of reactive oxygen species. In rat and mouse, a wide range of chemicals including polyaromatic hydrocarbons, azo dyes and quinones induces DTD. Bifunctional compounds, such as beta-naphthoflavone (beta-NF) and benzo(a)pyrene (B(a)P), induce DTD together with CYP1A and phase II enzymes by a mechanism involving the aryl hydrocarbon receptor (AHR). Monofunctional induction of DTD is mediated through the antioxidant response element and does not lead to the induction of AHR dependent enzymes, such as CYP1A. The aim of this study was to investigate the effects of prooxidants (both bifunctional and monofunctional) on the activity of hepatic DTD in rainbow trout (Oncorhynchus mykiss) in order to evaluate DTD suitability as a biomarker. We also investigated the effect of beta-NF on hepatic DTD activity in perch (Perca fluviatilis), shorthorn sculpin (Myoxocephalus scorpius), eelpout (Zoarces viviparus), brown trout (Salmo trutta) and carp (Cyprinus carpio). In addition, the effect of short term exposure to prooxidants on catalase activity was investigated. RESULTS: In rainbow trout, hepatic DTD activity is induced by the bifunctional AHR agonists beta-NF and B(a)P and the monofunctional inducers naphthazarin, menadione and paraquat. Although exposure to both B(a)P and beta-NF led to a strong 7-ethoxyresorufin-O-deethylase (EROD) induction, none of the monofunctional compounds affected the rainbow trout EROD activity. DTD was not induced by beta-NF in any of the other fish species. Much higher DTD activities were observed in rainbow trout compared to the other fish species. Catalase activity was less responsive to short term exposure to prooxidants compared to DTD. CONCLUSION: Since rainbow trout hepatic DTD activity is inducible by both monofunctional and bifunctional inducers, it is suggested that rainbow trout DTD may be regulated by the same mechanisms, as in mammals. The fact that DTD is inducible in rainbow trout suggests that the enzyme may be suitable as a part of a biomarker battery when rainbow trout is used in environmental studies. It appears as if DTD activity in rainbow trout is higher and inducible compared to the other fish species studied.
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PMID:Effects of redox cycling compounds on DT diaphorase activity in the liver of rainbow trout (Oncorhynchus mykiss). 1587 34

Ascorbic acid (AA) is one of the most important endogenous reducing agents and can participate in a variety of cellular events. In vitro, AA can act as a potent oxidant agent in the presence of free metals, promote modifications in protein structures and form reactive oxygen species during its oxidation. We have observed that AA (above 6 mmol/l) inactivates delta-aminolevulinate dehidratase (delta-ALA-D), a sulfhydryl-containing enzyme and that the inhibitory action was considerably decreased when 3-morpholinepropanesulfonic acid buffer (MOPS - pH: 6.8; 100 mmol/l) was used in the delta-ALA-D activity assay instead of potassium phosphate buffer (PB - pH: 6.8; 100 mmol/l). delta-ALA-D inhibition, probably, is mediated by the oxidation of -SH groups caused by the auto-oxidation of AA promoted by metals or another oxidizing system present in liver supernatants. This hypothesis was confirmed by studying dithiothreitol (DTT - 400 micromol/l) oxidation, as a model of enzyme thiols, where we observed that the mechanism underlying DTT and delta-ALA-D oxidation caused by ascorbate is the same. The difference observed between different buffers may be related to the oxidation of Fe(II) to Fe(III) that was more accentuated in PB than in MOPS buffer. The presence of ethilenediamintetraacetic acid (EDTA - 100 micromol/l) and Fe(III) (5 micromol/l) stimulated DTT oxidation more in PB than in MOPS buffer. Deferroxamine (DF - 100 micromol/l) considerably decreased DTT oxidation. Catalase (0.4 mg/ml) and Superoxide dismutase (SOD - 300 U/ml) had only a modest effect on DTT oxidation. The present results suggest that delta-ALA-D inhibition by AA is mediated primarily by the oxidized form of AA and reactive oxygen species play only a modest role in the process.
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PMID:Oxidation of delta-ALA-D and DTT mediated by ascorbic acid: modulation by buffers depends on free iron. 1607 98