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)

The involvement of oxidative mechanisms in the pathogenesis of rickettsiosis was investigated using infection of C3H/HeN mice with sub-lethal and lethal infectious doses of Rickettsia conorii, the causative agent of Mediterranean spotted fever. Microscopic examination of tissues at 48 and 96 h post-infection revealed characteristic pathologic features and the presence of rickettsiae in the endothelium of infected tissues. Activities of key antioxidant enzymes, namely glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase, and superoxide dismutase, at these times exhibited a pattern of differential and selective modulation in brain, lungs, and testes of mice infected with viable organisms, whereas heat-inactivated or sonically disrupted rickettsiae had no effect. Of these, most significant changes were evident in the lungs of infected animals. Adaptive alterations in oxidant-scavenging enzymes occurred in apparent correlation with the dose and duration of infection. Treatment with an antioxidant, alpha-lipoic acid, protected against infection-induced oxidative injury via regulation of antioxidant enzyme activities and maintenance of reduced glutathione levels. These results suggest the involvement of regulatory enzymes of glutathione redox and superoxide scavenging systems in the antioxidant response during in vivo infection, the extent of which varies with the titer of viable rickettsiae in different organs of the host.
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PMID:Selective modulation of antioxidant enzyme activities in host tissues during Rickettsia conorii infection. 1512 Jan 55

Effect of prefeeding dehydrated amaranth (A. gangeticus) leaves at 10 and 20% levels on a chemical toxicant, dimethylhydrazine (DMH)-induced free radical stress in rat liver was evaluated. DMH-induced rise in hepatic malondialdehyde (MDA), was diminished by AL. AL intake resulted in a significant increase in hepatic glutathione (GSH). The feeding of AL at 10% level increased the hepatic glucose-6-phosphate dehydrogenase (G-6-PDH) activity, while that at 20% level increased the hepatic glutathione reductase (GSSGR) as well, in addition to G-6-PDH. Amaranth leaves at 10 and 20% levels of feeding diminished the hepatic superoxide dismutase and glutathione peroxidase (GSH-Px) activities. DMH influenced adversely the hepatic antioxidant enzyme activities. Simultaneous administration of DMH and feeding of AL enhanced the DMH-induced decrease in hepatic GSH-Px. DMH enhanced formation of micronuclei was reverted significantly by AL intake. Hence, it was concluded that the consumption of AL at 20% level reduced DMH-induced impaired antioxidant status in rat liver.
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PMID:Effect of amaranth leaves on dimethylhydrazine-induced changes in multicomponent antioxidant system of rat liver. 1526 Jan 11

The aim of this study was to investigate effect of antiemetics on G6PD and antioxidant enzymes. Antiemetics are currently being used to reduce or prevent nausea and vomiting in patients. This is the first study to show effect of antiemetics on glucose-6-phosphate dehydrogenase (G6PD) and antioxidant enzyme activities. For in vitro studies, G6PD was purified from human erythrocyte, 10, 26-fold in a yield of 51.3% by using ammonium sulphate precipitation and 2',5'-ADP-Sepharose 4B affinity gel. The purified enzyme showed a single band on sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE). The effects of four different antiemetics (granisetron hydrochloride, ondansetron hydrochloride, metoclopramide hydrochloride, trimethobenzamide hydrochloride) were investigated on the purified enzyme. Granisetron hydrochloride and ondansetron hydrochloride inhibited the enzyme activity (Ki values; 5.05 mM and 0.034 mM, I50 values; 3.9 mM and 0.036 mM, respectively). Metoclopramide hydrochloride, trimethobenzamide hydrochloride showed no inhibition effects. In addition, in vivo studies, effects of ondansetron hydrochloride on the G6PD, glutathione reductase (GR), glutathione peroxidase (GPx) and catalase (CAT) were examined in the rat erythrocytes. G6PD (49% of control), GR (55% of control), CAT (60% of control) activities in erythrocytes were significantly decreased whereas GPx (183% of control) was significantly increased. A marked alteration in these enzymes may be result of oxidative stress in the rats receiving ondansetron hydrochloride.
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PMID:Effects of antiemetic drugs on glucose 6-phosphate dehydrogenase and some antioxidant enzymes. 1545 70

The effect of 3,4-di(OH)-phenylpropionic acid (L-phenylalanine methyl ester) amide (SL-1063), a synthetic derivative of 3,4-di(OH)-cinnamate, on the cholesterol metabolism and antioxidant enzyme system was examined in rats. Diets that included either SL-1063 (0.046%, w/w) or lovastatin (0.02%, w/w) as a supplement, plus 1 g cholesterol/100 g diet were fed to rats ad libitum for 5 weeks. The total plasma cholesterol and triglyceride levels were significantly lowered by the SL-1063 supplement compared to the control group. Meanwhile, the levels of plasma HDL-cholesterol and ratio of HDL-cholesterol/total cholesterol (%) were significantly higher in the SL-1063 group than in the control group. However, the lovastatin supplement did not affect the plasma lipid level. The hepatic cholesterol level and 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase activity were significantly lowered in the lovastatin group compared to the SL-1063 group; however, the hepatic triglyceride level did not differ among the groups. The activity of hepatic acyl CoA: cholesterol acyltransferase (ACAT), the enzyme that catalyzes hepatic cholesterol esterification, was significantly lower in the lovastatin and SL-1063 groups than in the control group. Furthermore, the SL-1063 supplement elevated the excretion of fecal sterols. As regards the hepatic antioxidant enzyme system, the superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione reductase (GR) activities were all significantly higher in the SL-1063 group compared to the control group, whereas only the GR activity was significantly increased by the lovastatin supplement. No marked difference in the GSH levels and glucose-6-phosphate dehydrogenase (G6PD) activities was observed among the groups. The levels of plasma and hepatic thiobarbituric acid reactive substances (TBARS) were lowered by the SL-1063 supplement compared to the control group. Accordingly, the current results suggest that SL-1063, a synthetic derivative of 3,4-di(OH)-cinnamate, is effective in lowering the plasma lipids and improving the antioxidant enzyme system.
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PMID:Effect of 3,4-di(OH)-cinnamate synthetic derivative on plasma and hepatic cholesterol level and antioxidant enzyme activities in high cholesterol-fed rats. 1554 4

In preliminary experiments it was found that Escherichia coli strains AB1157 and KS400 are different in their abilities to grow under various oxygen levels in cultivation medium: the first strain does not grow under high oxygen conditions, unlike the second one. To investigate whether the damage to cellular components due to production of reactive oxygen species (ROS) was responsible for this difference, the intensity of free radical oxidation of proteins and lipids as well as the activities of selected antioxidant and associated enzymes (superoxide dismutase, catalase, peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase) were compared in the two strains. The level of thiobarbituric acid-reactive substances was 1.8-2.5-fold higher in AB1157 than in KS400, but the concentration of carbonyl proteins was lower in the AB1157 strain. In both strains growth under higher oxygen levels resulted in higher superoxide dismutase and peroxidase activities in both exponential and stationary phases. Overall, the activities of antioxidant enzymes were always higher in the KS400 strain than in AB1157. The results for both lipid and protein oxidative damage and antioxidant enzyme activities suggest that the differences in oxygen tolerance between these two strains may be due to their different abilities to cope with ROS.
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PMID:Possible reasons for difference in sensitivity to oxygen of two Escherichia coli strains. 1589 8

The yeast Saccharomyces cerevisiae cells had higher antioxidant enzyme activities under growth in ethanol than that in glucose as a carbon and energy source. The correlations between catalase activity and protein carbonyl level (r(2)=0.857), between catalase and glucose-6-phosphate dehydrogenase activities (r(2)=0.924) and between protein carbonyl levels and glucose-6-phosphate dehydrogenase activity (r(2)=0.988) under growth in ethanol were found. Growing in ethanol the strain deficient in cytosolic and peroxisomal catalases had 7.1-fold higher level of carbonyl proteins than that of wild-type strain. Our data suggest that in vivo catalases may protect glucose-6-phosphate dehydrogenase against oxidative inactivation.
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PMID:Catalases protect cellular proteins from oxidative modification in Saccharomyces cerevisiae. 1589 81

Corticosteroids are anti-inflammatory drugs that are similar to the natural corticosteroid hormones produced by the cortex of the adrenal glands. The objective of this study was to scrutinize effects of some corticosteroids on glucose-6-phosphate dehydrogenase (G6PD) and some antioxidant enzymes. Initially, G6PD was purified from human erythrocytes by using ammonium sulphate precipitation and affinity chromatography. The two drugs, dexamethasone phosphate and prednisolone, investigated on the purified enzyme inhibited the enzyme activity. Comparative in vivo studies were performed to determine the effects of dexamethasone phosphate on the antioxidant enzyme activities using Spraque-Dawley rats. G6PD and catalase (CAT) activities were found significantly lower than in the control, whereas glutathione peroxidase (GP) activity was significantly increased in the erythrocytes of rats the receiving drug; glutathione reductase (GR) activity was unaffected. The results imply that dexamethasone phosphate may affect oxidative stress by changing antioxidant enzyme activities.
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PMID:Evaluation of effect of some corticosteroids on glucose-6-phosphate dehydrogenase and comparative study of antioxidant enzyme activities. 1589 80

An increasing amount of experimental and epidemiological evidence implicates the involvement of oxygen derived radicals in the pathogenesis of cancer development. It is well known that chemical carcinogenesis is multistage process. Free radicals arefound to be involved in both initiation and promotion of multistage carcinogenesis. Tamoxifen (TAM) is a potent antioxidant and a non-steroidal antiestrogen drug most used in the chemotherapy and chemoprevention of breast cancer. Besides its anticarcinogenic potential, it also produces some adverse toxic side effects, while taken for a long time. In order to minimise the side effects and to improve the antioxidant efficacy of tamoxifen, coenzyme Q10 (CoQ10) was added. Hence the present study was designed to investigate the combined efficacy of TAM along with CoQ10 in 7, 12 dimethyl benz(a)anthracene (DMBA) induced peroxidative damage in rat mammary carcinoma. The experimental setup comprised of one control and five experimental groups and it was carried out in adult female Sprague-Dawley rats. Mammary carcinoma was induced by oral administration of DMBA (25 mg kg(-1) body wt) and the treatment was started by the oral administration of TAM (10 mg kg(-1) body wt day(-1)) and CoQ10 (40 mg kg(-1) body wt day(-1)) dissolved in olive oil and continued for 28 days. Rats induced with DMBA showed a decline in the thiol capacity of the cell accompanied by high malondialdehyde content levels along with lowered activities of antioxidant status (superoxide dismutase, catalase, glutathione peroxidase and reduced glutathione). In contrast, glutathione metabolising enzymes (glutathione reductase, glucose-6-phosphate dehydrogenase and glutathione-S-transferase) were increased significantly in chemically induced carcinoma bearing rats. Administration of TAM along with CoQ10 restored the activities to a significant level thereby preventing cancer cell proliferation. This study highlights the increased antioxidant enzyme activities in relation to the susceptibility of cells to carcinogenic agents and the response of tumour cells to the chemotherapeutic agents.
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PMID:Combined efficacy of tamoxifen and coenzyme Q10 on the status of lipid peroxidation and antioxidants in DMBA induced breast cancer. 1601 50

We have shown that a single dose of streptozotocin (STZ) (50 mg/kg body weight) injected into rats caused significant changes in some antioxidant enzyme activities, such as glutathione peroxidase, glutathione reductase, glutathione-S-transferase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase activities, and acid-soluble sulfhydryl levels of the liver tissue with respect to the control rats. Furthermore, these alterations in the activities of the antioxidant enzymes were accompanied by significant changes in the ultrastructure of the liver tissue; mainly intercellular biliary canaliculi were distended and contained stagnant bile, swollen mitochondria in hepatocytes and disoriented and disintegrating cristae, dilatation of the rough endoplasmic reticulum (rER) with detachment of ribosomes, and dissociation of polysomes. Both diabetic and normal rats were treated with sodium selenite (5 micromol/kg/d, intra peritoneally) for 4 wk following 1 wk of diabetes induction. This treatment of diabetic rats improved significantly diabetes-induced alterations in liver antioxidant enzymes. Moreover, treating of diabetic rats with sodium selenite prevented primarily the variation in staining quality of hepatocytes nuclei, increased density and eosinophilia of the cytoplasm, focal sinusoidal dilatation and congestion, and increased numbers of mitochondria with different size and shape. In summary, treatment of diabetic rats with sodium selenite has beneficial effects on both antioxidant system and the ultrastructure of the liver tissue. These findings suggest that diabetes-induced oxidative stress can be responsible for the development of diabetic complications and antioxidant treatment can protect the target organs against diabetes.
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PMID:Selenium treatment protects diabetes-induced biochemical and ultrastructural alterations in liver tissue. 1603 59

Different kinds of oxidative stress cause responses of antioxidant defenses which often act in concert. In previous works, some relationships have been found between oxidative stress markers and antioxidant enzyme activities in goldfish treated with different levels of oxygen or heat shock. This study aimed to check whether or not there are general patterns of relationships between antioxidant enzyme activities and oxidative stress indices in goldfish tissues, regardless of the stressor. For this, goldfish were treated with different concentrations of iron sulphate, 20 or 500 microM, as well as limestone water for 7 days. Both iron ions and limestone water led to a pH shift. Therefore, complex effects of iron ions and/or a pH shift on levels of oxidative stress indices and antioxidant enzyme activities in goldfish liver and kidney were investigated. Experimental conditions resulted in increased protein carbonyl content by 1.5-1.9-fold. Externally added iron ions did not change lipid peroxide levels in the liver but decreased them in the kidney, while levels of thiobarbituric acid reactive substances (TBARS) were elevated by 1.4-2.5-fold. Limestone water raised levels of both lipid peroxidation products in the liver. The treatment affected activities of superoxide dismutase and catalase only slightly, but activities of glutathione-associated enzymes, glutathione-S-transferase (GST), glutathione reductase (GR), and glucose-6-phosphate dehydrogenase (G6PDH) were lowered in many cases. G6PDH activities correlated inversely with protein carbonyl levels (R2 = 0.77-0.97), suggesting possible inactivation of the enzymes due to their carbonylation. Levels of lipid peroxidation products had a positive correlation to activities of catalase in the liver and GR in the kidney (R2 = 0.83), indicating possible up-regulation of the enzymes by these products. A negative link between TBARS levels and GST activities may reflect the involvement of GST in the detoxification of lipid peroxide products. The main conclusions are: (i) experimental conditions resulted in increased levels of protein carbonyls and end products of lipid peroxidation (TBARS); (ii) under oxidative stress, some enzymes can be inactivated due to oxidation; (iii) lipid peroxidation products seem to be involved in up-regulation of some antioxidant enzymes.
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PMID:Coordinated response of goldfish antioxidant defenses to environmental stress. 1673 67


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