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)

Activated oxygen species produced during merocyanine 540 (MC540)-mediated photosensitization have been examined by electron spin resonance (ESR) spin trapping and by trapping reactive intermediates with salicylic acid using HPLC with electrochemical detection (HPLC-EC) for product analysis. Visible light irradiation of MC540 associated with dilauroylphosphatidylcholine liposomes in the presence of the spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) gave an ESR spectrum characteristic of the DMPO-hydroxyl radical spin adduct (DMPO/.OH). Addition of ethanol or methanol produced additional hyperfine splittings due to the respective hydroxyalkyl radical adducts, indicating the presence of free.OH.DMPO/.OH formation was not significantly inhibited by Desferal, catalase, or superoxide dismutase (SOD). Production of DMPO/.OH was strongly inhibited by azide and enhanced in samples prepared with deuterated phosphate buffer (PB-D2O), suggesting that singlet molecular oxygen (1O2) was an important intermediate. When MC540-treated liposomes were irradiated in the presence of salicylic acid (SA), HPLC-EC analysis indicated almost exclusive formation of 2,5-dihydroxybenzoic acid (2,5-DHBA), with production of very little 2,3-DHBA, in contrast to .OH generated by uv photolysis of H2O2, which gave nearly equimolar amounts of the two products. 2,5-DHBA production was enhanced in PB-D2O and inhibited by azide, again consistent with 1O2 intermediacy. 2,5-DHBA formation was significantly reduced in samples saturated with N2 or argon, and such samples showed no D2O enhancement. Ethanol had no effect on 2,5-DHBA production, even when present in large excess. Catalase and SOD also had no effect, and only a small inhibition was observed with Desferal. DMPO inhibited 2,5-DHBA production in a concentration-dependent fashion and enhanced formation of 2,3-DHBA. We propose that 1O2 reacts with DMPO to give an intermediate which decays to form DMPO/.OH and free.OH, and that the reaction between 1O2 and SA preferentially forms the 2,5-DHBA isomer. This latter process may provide the basis for a sensitive analytical method to detect 1O2 intermediacy. Singlet oxygen appears to be the principle activated oxygen species produced during MC540-mediated photosensitization.
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PMID:Production of singlet oxygen-derived hydroxyl radical adducts during merocyanine-540-mediated photosensitization: analysis by ESR-spin trapping and HPLC with electrochemical detection. 165 88

Copper Fenton systems (Cu(II)/H2O2 and Cu(II)/Asc) inactivated the lipoamide reductase and enhanced the diaphorase activity of pig-heart lipoamide dehydrogenase (LADH). Cupric ions alone were less effective. As a result of Cu(II)/H2O2 treatment, the number of titrated thiols in LADH decreased from 6 to 1 per subunit. NADH and ADP (not NAD+ or ATP) enhanced LADH inactivation by Cu(II). NADH also enhanced the effect of Cu(II)/H2O2. Dihydrolipoamide, dihydrolipoic acid, Captopril, acetylcysteine, EDTA, DETAPAC, histidine, bathocuproine, GSSG and trypanothione prevented LADH inactivation. 100 microM GSH, DL-dithiothreitol, N-(2-mercaptopropionylglicine) and penicillamine protected LADH against Cu(II)/Asc and Cu(II), whereas 1.0 mm GSH and DL-dithiothreitol also protected LADH against Cu(II)/H2O2. Allopurinol provided partial protection against Cu(II)/H2O2. Ethanol, mannitol, Na benzoate and superoxide dismutase failed to prevent LADH inactivation by Cu(II)/H2O2 or Cu(II). Catalase (native or denaturated) and bovine serum albumin protected LADH but that protection should be due to Cu binding. LADH inhibited deoxyribose oxidation and benzoate hydroxylation by Cu(II)/H2O2. It is concluded that site-specifically generated HO, radicals were responsible for LADH inactivation by Cu(II) Fenton systems. The latter effect is discussed in the context of ischemia-reoxygenation myocardial injury.
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PMID:Inactivation of heart dihydrolipoamide dehydrogenase by copper Fenton systems. Effect of thiol compounds and metal chelators. 775

The neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been shown to generate reactive oxygen species during its interaction with monoamine oxidase type B (MAO-B). The kinetic parameters, Km and Vmax, for MAO-B-catalyzed oxidation of MPTP to the corresponding species MPDP+ were found to be 0.194 mM and 0.335 microM/min, respectively. The generation of superoxide (.O2-) and hydroxyl (.OH) radicals was detected as the 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) spin adduct by spin-trapping in combination with EPR techniques. Addition of Fe2+ (10 microM) to this system caused a 5-fold enhancement in EPR signal intensity of the DMPO-OH adduct. Catalase, a scavenger of hydrogen peroxide (H2O2), inhibited the DMPO-OH spin adduct formation in a dose-dependent manner, indicating that H2O2 is produced in the MAO-B catalyzed oxidation of MPTP. Ethanol, a well known scavenger of hydroxyl radical, rapidly produced an alpha-hydroxyethyl radical signal. Superoxide dismutase inhibited the formation of DMPO-O2- and DMPO-OH spin adducts in a dose-dependent fashion. These data suggest that superoxide radicals are produced during the oxidation of MPTP by MAO-B and that the generation of H2O2 and .OH was secondary to the production of .O2-. It appears likely that the nigrostriatal toxicity of MPTP leading to Parkinson's disease-like syndrome may in part be mediated via these reactive oxygen species.
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PMID:Generation of reactive oxygen species during the monoamine oxidase-catalyzed oxidation of the neurotoxicant, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. 839 68

Ethanol can be oxidized to the 1-hydroxyethyl radical (HER) by rat and deer mice liver microsomal systems. Experiments were carried out to evaluate the ability of human liver microsomes to catalyze this reaction, compare the effectiveness of NADH with that of NADPH, and assess the possible role of cytochrome b5 in HER formation. HER was detected as the alpha-(4-pyridly-1 -oxide)-N-t-butylnitrone/HER adduct. Human liver microsomes catalyzed HER formation with either NADPH or NADH as cofactor; rates with NADH were approximately 50% those found with NADPH. Chelex-100 treatment of the reaction mixture produced marked inhibition of HER formation, suggesting that a transition metal, such as iron, was required to catalyze the reaction. The addition of ferric chloride restore HER formation. Catalase (2600 units/ml) and superoxide dismutases (500 units/ml) nearly completely inhibited the reaction with either NADPH or NADH. The NADH-dependent rates of superoxide production, detected as 5,5-dimethyl-1-pyrroline-N-oxide-O2H, were approximately 50% the NADPH-dependent rates, which is consistent with the rates of HER formation. Anti-cytochrome b5 IgG decreased NADPH- and NADH-dependent HER formation, and this was associated with inhibition of superoxide formation with both reductants. These results indicate that human liver microsomes can catalyze the oxidation of ethanol of HER with either NADPH or NADH as reductant. The effectiveness of NADH may be significant in view of the increased NADH/NAD+ redox ratio in the liver as a consequence of ethanol oxidation by alcohol dehydrogenase. HER formation by human liver microsomes seems to be catalyzed by an oxidant derived from the interaction of iron with superoxide or H2O2, and a close association exists between HER formation and superoxide production. Cytochrome b5 seems to play a role in HER formation, most likely due to its effect on superoxide production.
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PMID:1-Hydroxyethyl radical formation during NADPH- and NADH-dependent oxidation of ethanol by human liver microsomes. 862 31

This study investigates the interactive effects of chronic ethanol ingestion and exercise training on the antioxidant system and lipid peroxidation in cortex, cerebellum, medulla, striatum and hypothalamus of the rat brain. Exercise training (6.5 weeks) significantly increased superoxide dismutase (SOD) activity in striatum, the region associated with motor activity, but decreased SOD activity in other brain regions. Catalase (CAT) activity decreased significantly in hypothalamus, the region associated with behavior, due to exercise. The training significantly increased glutathione peroxidase (GSH-Px) activity in brain regions studied with the exception of cerebellum. In addition, glutathione reductase (GR) activity increased in brain regions, with the exception of medulla. The training significantly decreased malondialdehyde (MDA) levels in all brain regions studied, which is due to training adaptation. Ethanol (20%) (2.0 g kg[-1], p.o. for 6.5 weeks) significantly decreased SOD activity in all regions except cortex, CAT activity in cortex, striatum and hypothalamus, GSH-Px activity in cerebellum and GR activity in medulla. Similarly, ethanol significantly decreased the GSH level in cortex, medulla and striatum and the GSH/GSSG ratio in medulla and cerebellum. Conversely, ethanol significantly augmented GR activity in cortex, cerebellum and striatum. When ethanol and exercise were combined, there was significantly increased SOD and CAT activity in striatum, GSH-Px activity in cortex, striatum and hypothalamus and GR activity in cortex and striatum. The GSH level was significantly depleted in cortex, striatum and medulla. Combining training and ethanol also decreased MDA levels in medulla and cerebellum. In conclusion, the sensitivity of specific brain regions in reaction to chronic ethanol ingestion or training is a function of variability in antioxidant system activity. Thus, exercise training protects specific brain regions against ethanol-induced oxidative injury.
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PMID:Interaction of exercise training and chronic ethanol ingestion on antioxidant system of rat brain regions. 933 46

Impairment of mitochondrial functions has been found in ethanol-induced liver injury. Ethanol can be oxidized to the 1-hydroxyethyl radical (HER) by rat liver microsomal systems. Experiments were carried out to evaluate the ability of HER to cause mitochondrial swelling as an indicator of the mitochondrial permeability transition (MPT). Electron spin resonance (ESR) spectroscopy was used to detect HER and to study its interaction with mitochondria. The ESR signal intensity of the spin adduct formed from alpha-(4-pyridyl-1-oxide) N-tert-butylnitrone (POBN) and HER generated from either a thermic decomposition of 1,1'-dihydroxyazoethane (DHAE) or a Fenton reaction system containing ethanol was markedly diminished by the addition of mitochondria, indicating an interaction between HER and mitochondria. Exposure of rat liver mitochondria to HER generated from either system caused swelling, as reflected by a decrease in absorbance at 540 nm, in a HER concentration-dependent and a cyclosporin A-sensitive manner. Mitochondrial swelling was also induced in the Fenton reaction system without ethanol. The DHAE-dependent generation of HER in mitochondrial suspension resulted in a decrease of membrane protein thiols and collapse of the membrane potential (delta psi). The swelling induced by HER was prevented by glutathione and vitamin E, but not by superoxide dismutase. Catalase did not prevent the swelling caused by the acetaldehyde/hydroxylamine O-sulfonate (HOS) system, but was inhibitory in the Fenton reaction system with or without ethanol. These results indicate that HER, as well as hydroxyl radical, can induce the MPT, and suggest the possibility that the collapse of delta psi caused by HER may, at least in part, contribute to impairment of mitochondrial function caused by ethanol and in ethanol-induced liver injury.
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PMID:Mitochondrial permeability transition induced by 1-hydroxyethyl radical. 1128 Dec 95

Research has suggested that catalase plays a role in mediating ethanol's psychopharmacological effects. Catalase is an enzyme that oxidizes ethanol to acetaldehyde. It has been reported that when catalase activity is reduced by 3-amino-1,2,4-triazole (AT), rats reduce their intake and preference for ethanol. The present study assessed the effects of AT on the brain amino acids levels following ethanol administration in Wistar rats. The study consisted of three parts. In the first part, we found no effects of acute and chronic intraperitoneally administered acetaldehyde on amino acids dialysate levels in nucleus accumbens. In the second part, AT was administered five hours prior to ethanol or its vehicle. Ethanol significantly affected the levels of taurine in rat pre-treated with AT. In the final part, ethanol was administered following the pre-treatment with AT but the dependent variable was the concentration of ethanol in the brain.
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PMID:Ethanol but not acetaldehyde induced changes in brain taurine: a microdialysis study. 1504 39

In forensic medicine practice poisonings are rather frequent, and among them, those caused by fatal "substitution" of ethyl alcohol. One of the most frequently encountered "substitutes" for ethyl alcohol is methanol. The purpose of our research was to determine the concentration of malonic dialdehyde as the expression of lipid peroxidation and antioxidant enzyme activity after dosed chronic ethyl and methyl alcohol intoxication. The experiment was conducted on approx. 6 month-old male inbred Lewis rats each weighing approx. 250 g. Ethanol and methanol solution was given in the concentration 1.0 M. The control group of rats received water. Each experimental group numbered 30 rats, this number was divided into three sub-groups, which were put-down at 4, 8 and 12 weeks. The activity of superoxide dismutase (CuZu-SOD) was determined by the Misra-Fridovich method, catalase (CAT) by the Beers-Sizer method. The concentration of malonic dialdehyde (MDA) was determined using the method of Placer et al. by assessing the concentration of TBARS compounds. Results are expressed as a mean +/- SD. The paired Student's test for small groups were used. Superoxide dismutase SOD1 activity decreased compared with the control group throughout the duration of the experiment from 2212 U/gHb to 1676 U/gHb for ethanol and from 2212 U/gHb to 945 U/gHb for methanol. Catalase activity for methanol decreased from 9.1 U/gHb to 5.1 U/gHb, for ethanol to 7.4 U/gHb. In the 4th week of the experiment increase of malonyl dialdehyde concentration for methanol group was observed--from 0.14 umol/gHb to 0.34 umol/Hb; after 8th weeks it decreased to 0.2 umol/gHb and in the 12th week increased to 0.23 umol/gHb. For ethanol these changes was less visible and reached the level of 0.24 umol/l. The statistical processing of the results was performed on the basis of parametric tests (the t-Student test for small experiments) and computer software Statistica. The statistical significance was set for p<0.05.
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PMID:[Selected alcohols on the pro- and anti-oxidative processes in rat erythrocytes]. 1549 56

The promoting effect of ethanol against the cytotoxicity of hydrogen peroxide (H2O2) in differentiated PC12 cells was assessed by measuring the effect on the mitochondrial membrane permeability. Treatment of PC12 cells with H2O2 resulted in the nuclear damage, decrease in the mitochondrial transmembrane potential, cytosolic accumulation of cytochrome c, activation of caspase-3, increase in the formation of reactive oxygen species (ROS) and depletion of GSH. In PC12 cells and dopaminergic neuroblastoma SH-SY5Y cells, the promoting effect of ethanol on the H2O2-induced cell death was increased with exposure time. Ethanol promoted the nuclear damage, change in the mitochondrial membrane permeability, ROS formation and decrease in GSH contents due to H2O2 in PC12 cells. Catalase, carboxy-PTIO, Mn-TBAP, N-acetylcysteine, cyclosporin A and trifluoperazine inhibited the H2O2 and ethanol-induced mitochondrial dysfunction and cell injury. The results show that the ethanol treatment promotes the cytotoxicity of H2O2 against PC12 cells. Ethanol may enhance the H2O2-induced viability loss in PC12 cells by promoting the mitochondrial membrane permeability change, release of cytochrome c and subsequent activation of caspase-3, which is associated with the increased formation of ROS and depletion of GSH. The findings suggest that ethanol as a promoting agent for the formation of mitochondrial permeability transition may enhance the neuronal cell injury caused by oxidants.
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PMID:Synergistic effects of hydrogen peroxide and ethanol on cell viability loss in PC12 cells by increase in mitochondrial permeability transition. 1592 45

Although the mechanism of ethanol toxicity during embryogenesis is unknown, our earlier studies on Japanese rice fish (Oryzias latipes) embryos indicated that the effects might be mediated through oxidative stress. In this study we have determined the oxidative stress and the mRNA content of four antioxidant enzymes (catalase, glutathione reductase, glutathione-S-transferase, and superoxide dismutase) during Japanese rice fish embryogenesis (from 0 day post-fertilization to hatching) and after exposing the embryos to ethanol (100 and 300 mM) for 48 h at three stages (0-2, 1-3 and 4-6 days post-fertilization, dpf) of organogenesis. We observed that oxidative stress was minimal in blastula, gastrula or neurula stages, increased gradually with the advancement of morphogenesis and reached its maximum level in hatchlings. The antioxidant enzyme mRNAs were constitutively expressed throughout development; however, the expression pattern was not identical among the enzymes. Catalase and superoxide dismutase (SOD) mRNAs were minimal in the fertilized eggs, but increased significantly in 1 dpf and then either sharply dropped (SOD) or maintained a steady-state (catalase). Glutathione-S-transferase (GST) was very high in fertilized eggs and sharply dropped 1 dpf and then gradually increased thereafter. Glutathione reductase (GR) maintained a steady-state throughout the development. Ethanol was able to attenuate oxidative stress in embryos exposed only to 300 mM 1-3 dpf; no significant difference with controls was observed in other ethanol-treated groups. The antioxidant enzyme mRNAs also remained unaltered after ethanol treatment. From these data we conclude that the attenuation of oxidative stress by ethanol is probably due to the inhibition of normal growth of the embryos rather than by inhibiting catalase, GST, GR or SOD-dependent activities.
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PMID:Ethanol-induced attenuation of oxidative stress is unable to alter mRNA expression pattern of catalase, glutathione reductase, glutathione-S-transferase (GST1A), and superoxide dismutase (SOD3) enzymes in Japanese rice fish (Oryzias latipes) embryogenesis. 2096 76


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