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)

Increasing attention has been given recently to the role of free radicals in the pathogenesis of ulcerative colitis, since the inflamed intestine is exposed to oxidative stress generated by infiltrating macrophages and neutrophils within the lamina propia. The overall goal of this study was to evaluate whether experimental ulcerative colitis induces significant changes in the antioxidant defense system in an experimental model induced by the intrarectal administration of 2,4,6-trinitrobenzenesulfonic acid. Twenty rats were treated with 80 mg/kg body weight of trinitrobenzenesulfonic acid and 20 with the same volume of 0.9% NaCl. Rats were killed at one and two weeks after treatment to evaluate colon damage by light and electron transmission microscopy. The degree of tissue injury and inflammation was determined by measuring alkaline phosphatase, gamma-glutamyltranspeptidase, and myeloperoxidase activities and prostaglandin E2 and leukotriene B4. Glutathione levels and the activity of the enzymes of the antioxidant defense system were determined. Enzymatic markers of colon injury showed higher activities in rats with ulcerative colitis. Concentrations of prostaglandin E2 and leukotriene B4 were higher in the groups treated for one week with trinitrobenzenesulfonic acid and markers decreased after two weeks of treatment. All antioxidant enzyme activities were higher at one and two weeks after treatment; however, a significant decrease in total glutathione content was also observed. In conclusion, ulcerative colitis induced by trinitrobenzenesulfonic acid damages the intestinal mucosa and is accompanied by a shift in the antioxidant enzyme activities, and low levels of glutathione. This deficiency in glutathione could be a target for new therapies to treat ulcerative colitis.
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PMID:Experimental ulcerative colitis impairs antioxidant defense system in rat intestine. 1105 26

There has been no investigation to determine if the widely used over-the-counter, water-soluble antioxidants vitamin C and N-acetyl-cysteine (NAC) could act as pro-oxidants in humans during inflammatory conditions. We induced an acute-phase inflammatory response by an eccentric arm muscle injury. The inflammation was characterized by edema, swelling, pain, and increases in plasma inflammatory indicators, myeloperoxidase and interleukin-6. Immediately following the injury, subjects consumed a placebo or vitamin C (12.5 mg/kg body weight) and NAC (10 mg/kg body weight) for 7 d. The resulting muscle injury caused increased levels of serum bleomycin-detectable iron and the amount of iron was higher in the vitamin C and NAC group. The concentrations of lactate dehydrogenase (LDH), creatine kinase (CK), and myoglobin were significantly elevated 2, 3, and 4 d postinjury and returned to baseline levels by day 7. In addition, LDH and CK activities were elevated to a greater extent in the vitamin C and NAC group. Levels of markers for oxidative stress (lipid hydroperoxides and 8-iso prostaglandin F2alpha; 8-Iso-PGF2alpha) and antioxidant enzyme activities were also elevated post-injury. The subjects receiving vitamin C and NAC had higher levels of lipid hydroperoxides and 8-Iso-PGF2alpha 2 d after the exercise. This acute human inflammatory model strongly suggests that vitamin C and NAC supplementation immediately post-injury, transiently increases tissue damage and oxidative stress.
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PMID:Supplementation with vitamin C and N-acetyl-cysteine increases oxidative stress in humans after an acute muscle injury induced by eccentric exercise. 1155 12

Previous studies from this lab have shown NO-mediated modulation of free radical generation from polymorphonuclear leukocytes (PMNs), following hypoxic-reoxygenation as well as in the normoxic cells. The present study is an attempt to investigate further the regulation of NO and free radical generation in the lipopolysaccharide (LPS)-treated PMNs. PMNs were isolated from the rat blood and peritoneal cavity, 4 h after LPS (1 mg/kg, i.p.) treatment. Nitric oxide synthase (NOS) activity and nitrite content were increased in the peripheral and peritoneal PMNs following LPS treatment. An increase in the apparent V(max) for l-arginine uptake was also observed in the LPS-treated peripheral PMNs, while peritoneal PMNs exhibited increase in both apparent V(max) and affinity for l-arginine. Synthesis of nitrite did not augment after increasing the availability of substrate to control PMNs, however, peripheral and peritoneal PMNs from LPS-treated rats utilized l-arginine more efficiently for nitrite synthesis. NOS activity, l-arginine uptake, and its utilization were maximal in the peritoneal PMNs. Arachidonic acid (AA, 1 x 10(-6) M)-induced free radical generation from PMNs was also enhanced significantly after LPS treatment. Preincubation of PMNs with nitrite elevated the free radical generation and myeloperoxidase (MPO) release. MPO and antioxidant enzyme activity in the PMNs was significantly augmented after LPS treatment. NOS inhibitors, aminoguanidine and 7-nitroindazole, inhibited arachidonic acid-induced free radical generation from LPS treated PMNs. The results obtained thus indicate that augmentation of free radical generation from rat PMNs following LPS treatment appears to be regulated by NO and MPO.
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PMID:Nitric oxide- and oxygen-derived free radical generation from control and lipopolysaccharide-treated rat polymorphonuclear leukocyte. 1158 63

Olive oil, the main fat component of the Mediterranean diet, has been found to be protective against oxidative stress and could be beneficial in inflammatory and gastrointestinal disorders. First-pressed, extra-virgin olive oil (EVOO) has appreciable amounts of powerful antioxidants such as polyphenolic compounds that prevent its autoxidation and are responsible for its high stability. The aim of the present study was to determine whether diets supplemented with EVOO could reduce the severity of indomethacin-induced gastric oxidative damage and also to study changes in the activities of certain oxidative stress-related enzymes such as xanthine oxidase, myeloperoxidase as a marker of neutrophil infiltration, and the antioxidant enzyme superoxide dismutase. Lipid peroxidation and possible modifications in gluthatione metabolism were also studied. Weanling rats were maintained on semisynthetic diet for 6 weeks; a standard diet containing 5% (w/w) of fat as control or EVOO supplemented diets (5% and 20% w/w). Gastric lesions were induced on the last day by oral administration of indomethacin (60 mg/kg body wt). In animals fed EVOO diets, gastric lesions were decreased significantly and in parallel with dietary fat, when compared to animals consuming a standard diet. These protective effects were related to a reduction of lipid peroxides generation, neutrophil infiltration, and xanthine oxidase activity. Superoxide dismutase, an important enzyme to scavenger of lipid peroxides, was unaffected by feeding conditions. On the other hand, dietary supplementation with EVOO significantly increased both glutathione peroxidase activity and total glutathione content. In conclusion, this study provides evidence that fat diets containing EVOO reduces indomethacin-induced gastric damage in rats. This effect may be partly due not only to reducing oxidative stress and neutrophil-induced toxicity but also to enhancing the glutathione antioxidant defense system.
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PMID:Extra-virgin olive oil-enriched diets reduce indomethacin-induced gastric oxidative damage in rats. 1249 2

In this study, the main antioxidant enzymes (AOE) of glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT) and myeloperoxidase (MPO) were identified, and the influence of sex and age in healthy human polymorphonuclear leukocytes (PMNL) was determined. The SOD, GPX, CAT and MPO activities were investigated in intestinal parasite negative human PMNL from 109 healthy subjects aged from 6 to 70 years (55 males and 54 females) using simple and sensitive enzyme assays. Blood cells, such as eosinophils, platelets, neutrophils, monocytes, and macrophages also synthesize antioxidant enzymes (AOE). They constitute an important proportion and are also the major participants in a number of pathological conditions that suggest the involvement of AOE. A linear effect of age on SOD activity (p < 0.05) both in males and females was found. A similar effect with GPX activity (p < 0.05) was observed in males only. This showed that the activities of all these enzymes increase with age. In addition, SOD activity was significantly higher in females than males between the age of 19 and 70 years (p < 0.001). This analysis also showed that there is a negative correlation between the CAT-GPX (p < 0.05) activities and positive correlations between MPO-GPX (p < 0.05) activities only in females. No correlation among the other enzyme activities was found in either sex group. This study showed the activities of antioxidant enzyme activities and the correlations of these enyzmes activities with each other in healthy human PMNLs were age- and sex-dependent. This information may assisit in understanding the importance of antioxidant enzymes in the physiological and pathological conditions associated with PMNL.
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PMID:Influence of sex and age on the activity of antioxidant enzymes of polymorphonuclear leukocytes in healthy subjects. 1261 69

Chloroacetonitrile (CAN) is a disinfection by-product of chlorination of drinking water. Epidemiological studies indicate that it might present a potential hazard to human health. The present work provides an evidence for CAN activation to cyanide (CN-) by myeloperoxidase (MPO)/hydrogen peroxide (H2O2)/chloride (Cl-) system in vitro. Optimum conditions for the oxidation of CAN to CN- were characterized with respect to pH, temperature and time of incubation as well as CAN, MPO, H2O2 and KCl concentrations in incubation mixtures. The kinetic parameters governing the reaction; maximum velocity (Vmax) and Michaelis-Menten constant (Km) were assessed. Oxidation of CAN to CN- by NaOCl alone was shown. Addition of the MPO inhibitors; sodium azide (NaN3), 4-amino benzoic acid hydrazine (ABAH) or indomethacin to the reaction mixtures resulted in a significant decrease in the rate of CAN oxidation. Inclusion of the antioxidant enzyme catalase (CAT) in the incubation mixtures resulted in a significant decrease in the rate of CAN oxidation and CN- formation. Addition of the sulfhydryl compounds; glutathione (GSH), N-acetyl-L-cysteine (NAC), L-cysteine or D-penicillamine significantly enhanced the rate of CN- release. In conclusion, MPO/H2O2/Cl- system has the ability of oxidizing CAN to CN-. The present results represent a novel pathway for CAN activation and might be important in explaining CAN-induced toxicity.
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PMID:Myeloperoxidase-catalyzed oxidation of chloroacetonitrile to cyanide. 1468 62

We have investigated the effect of caffeic acid phenethyl ester (CAPE) on cisplatin-induced nephrotoxicity in rats. Administration of a single dose of cisplatin resulted in the elevation of blood urea nitrogen and creatinine in serum, as well as nitric oxide in kidney tissue of rats. Cisplatin also caused reduction of catalase (P < 0.0001), superoxide dismutase (P = 0.149) and glutathrone peroxidase (P < 0.0001) activities in kidney tissue. Although cisplatin caused elevation in malondialdehyde levels and myeloperoxidase activities in kidney tissue, they were not statistically significant. Caffeic acid phenethyl ester was found to be protective against cisplatin-induced antioxidant enzyme reductions. Treatment with free-radical scavenger CAPE attenuated the increase in plasma blood urea nitrogen and kidney nitric oxide levels, and showed histopathological protection against cisplatin-induced acute renal failure. Extensive epithelial cell vacuolization, swelling, desquamation and necrosis were observed in the kidney of the cisplatin-treated rat. There were also larger tubular lumens in cisplatin-treated rats than those of the control and the CAPE groups. Caffeic acid phenethyl ester caused a marked reduction in the extent of tubular damage. It is concluded that administration of cisplatin imposes an oxidative stress to renal tissue and CAPE confers protection against the oxidative damage associated with cisplatin. This mechanism may be attributed to its free-oxygen-radical scavenging activity.
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PMID:Role of caffeic acid phenethyl ester, an active component of propolis, against cisplatin-induced nephrotoxicity in rats. 1474 44

The aim of the present study was to determine the effects of erdosteine, a new antioxidant and anti-inflammatory agent, on lipid peroxidation, neutrophil infiltration, and antioxidant enzyme activities in a rat model of renal ischemia-reperfusion (I/R) injury. Twenty-eight rats were divided into three groups: sham operation, I/R, and I/R plus erdosteine groups. After the experimental procedure, rats were sacrificed and kidneys were removed and prepared for malondialdehyde (MDA) levels, myeloperoxidase (MPO), xanthine oxidase (XO), catalase (CAT) and superoxide dismutase (SOD) activities. MDA level, MPO and XO activities were significantly increased in the I/R group. On the other hand, SOD and CAT activities were found to be decreased in the I/R group compared to the sham group. Pretreatment with erdosteine significantly diminished tissue MDA level, MPO and XO activities. Our data support a role for erdosteine in attenuation in renal damage after I/R injury of the kidney, in part at least by inhibition of neutrophil sequestration and XO activity.
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PMID:Erdosteine improves oxidative damage in a rat model of renal ischemia-reperfusion injury. 1526 25

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a transcription factor that regulates the expression of various gene products that are essential in lipid and glucose metabolism, as well as that of the peroxisome-enriched antioxidant enzyme, catalase. Activation of PPARgamma is linked to anti-inflammatory activities and is beneficial for cardiovascular diseases. However, little is known about its role in intracerebral hemorrhage (ICH). 15-Deoxy-Delta(12,14)-prostaglandin J2 (15d-PGJ2) acts as a physiologic agonist for PPARgamma. In this study, we found that injection of 15d-PGJ2 into the locus of striatal hematoma increased PPARgamma-deoxyribonucleic acid (DNA) binding activity and the expression of catalase messenger ribonucleic acid (mRNA) and protein in the perihemorrhagic area. Additionally, 15d-PGJ2 significantly reduced nuclear factor-kappaB (NF-kappaB) activation and prevented neutrophil infiltration measured by myeloperoxidase (MPO) immunoassay, and also reduced cell apoptosis measured by terminal deoxynucleotide transferase dUTP nick-end labeling (TUNEL). In addition, 15d-PGJ2 reduced behavioral dysfunction produced by the ICH. Altogether, our findings indicate that injection of 15d-PGJ2 at the onset of ICH is associated with activation of PPARgamma and elevation of catalase expression, suppression of NF-kappaB activity, and restricted neutrophil infiltration. All these events predicted reduced behavioral deficit and neuronal damage.
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PMID:15d-Prostaglandin J2 activates peroxisome proliferator-activated receptor-gamma, promotes expression of catalase, and reduces inflammation, behavioral dysfunction, and neuronal loss after intracerebral hemorrhage in rats. 1620 15

Cisplatin is one of the most active cytotoxic agents in the treatment of cancer. High doses of cisplatin have also been known to produce hepatotoxicity. Several studies suggest that supplementation with an antioxidant can influence cisplatin-induced hepatotoxicity. The present study was designed to determine the effects of cisplatin on the liver oxidant/antioxidant system, and the possible protective effects of caffeic acid phenethyl ester (CAPE) on liver toxicity induced by cisplatin. Twenty-four adult female Wistar albino rats were divided into four groups of six rats each: control, cisplatin, CAPE, and cisplatin+CAPE. Cisplatin and CAPE were injected intraperitoneally. Liver tissue was removed to study the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), myeloperoxidase (MPO), xanthine oxidase (XO), adenosine deaminase (ADA), and the levels of malondialdehyde and nitric oxide (NO). The activities of SOD and GSH-Px increased in the cisplatin+CAPE and CAPE groups compared with the cisplatin group. CAT activity was higher in the cisplatin +CAPE group than the other three groups. XO activity was lower in the cisplatin group than the control group. MPO activity was also increased in the cisplatin group compared to the control and CAPE groups. It can be concluded that CAPE may prevent cisplatin-induced oxidative changes in liver by strengthening the antioxidant defence system by reducing reactive oxygen species and increasing antioxidant enzyme activities.
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PMID:Protective effect of caffeic acid phenethyl ester (CAPE) administration on cisplatin-induced oxidative damage to liver in rat. 1643 19


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