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)

Rat Sertoli and germ cells express extracellular superoxide dismutase (SOD(EX)), however, the relative level of SOD(EX) expressed by these cells was not known. We report herein germ cells consisting largely of spermatogonia, spermatocytes, and round spermatids expressed only one-third SOD(EX) as that of Sertoli cells when examined by semi-quantitative RT-PCR. While cocultures of germ cells with Sertoli cells failed to induce any changes in SOD(EX) expression possibly due to the limited number of cells that can be supported by the in vitro culture system dissimilar to the in vivo condition, incubation of total germ cell-conditioned medium with Sertoli cells was able to significantly inhibit Sertoli cell SOD(EX) expression dose-dependently suggesting a germ cell-derived soluble factor(s) may regulate SOD(EX) in the testis. On the other hand, cytokines such as TGF-beta1, beta-NGF, or FGF and steroid hormones such as estradiol-17beta, progesterone, testosterone, and DHT were unable to effect the expression of Sertoli cell SOD(EX). However, FSH at 100 ng/dish was able to induce a significant increase in Sertoli cell SOD(EX) expression. While cytokines, the known mediators of the inflammatory response, were unable to affect Sertoli cell SOD(EX) expression, the induction of generalized inflammation in vivo was able to cause a 2- to 2.5-fold increase in testicular SOD(EX) expression concomitant with a transient increase in the liver but not in the brain. Taken collectively, these results demonstrate that while SOD(EX) is an important antioxidant enzyme protecting the testis from reactive oxygen species, the mechanism(s) regulating its expression may involve an array of molecules and is a complicated cellular event.
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PMID:In vitro regulation of extracellular superoxide dismutase in sertoli cells. 1090 Dec 81

Experimental rats with hypertriglyceridemia were prepared by feeding a high-fructose diet. Dried Anka powder (2%), a rice product fermented with Monascus sp., was mixed with basic high-fructose (30%) or basal-diet feed. Serum and liver lipids were measured after 6 months. The concentrations of serum triglycerides, total cholesterol, VLDL-C, and LDL-C had significantly decreased, whereas that of HDL-C had slightly increased in 30% fructose-Anka-fed rats as compared with the 30% fructose-fed rats, but hepatic lipase activity had increased in the Anka-fed groups. The ratio of lipoprotein lipase/hepatic lipase was not significantly different between 30% fructose-Anka-fed rats and 30% fructose-fed rats. The dietary intake and weight of these two groups were approximately the same. Similar results were obtained in noninduced hypertriglyceridemic rats. The concentrations of triglycerides and cholesterol did not significantly differ in the liver. Interestingly, Anka can suppress serum triglycerides in rats with induced hypertriglyceridemia. The antioxidant enzyme SOD activity was also measured in serum, and no significant change was observed. On the basis of these findings, we suggest that Anka may be used to suppress hypertriglyceridemia and hyperlipidemia in rats and possibly in man.
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PMID:Hypotriglyceridemic effect of Anka (a fermented rice product of monascus sp.) in rats. 1095 89

Antioxidant defense system prevents the organism from the detrimental effects of free radicals via scavenging or inhibiting their formation. Changes in the antioxidant defense mechanisms and alterations of several essential trace elements in both plasma and various tissues of ob/ob mice have been reported previously. Recent finding of the restoration of the defective antioxidant enzyme activity after leptin treatment in ob/ob mice suggests a putative role of leptin in modulation of antioxidant enzyme activity. Therefore, the aim of this study was to investigate whether antioxidant enzymes and trace elements could also be altered in patients with leptin gene mutation. Seven patients (five men and two women, two of them are homozygous and 5 are heterozygous) with leptin gene mutation and 31 healthy, sex- and age-matched and non-related to the patients (24 male and 9 female), control volunteers were enrolled in the study. Plasma and erythrocyte glutathione peroxidase (GSH-Px) and erythrocyte copper-zinc superoxide dismutase (CuZn-SOD) activities were measured spectrophotometrically. Plasma selenium (Se), manganese (Mn), zinc (Zn), copper (Cu), and iron (Fe) levels were measured by atomic absorption spectrophotometry. Mean Cu and Fe levels in patients were not significantly different than those in controls whereas mean Se, Zn and Mn levels were significantly lower in patients than those of controls (P=0.007, P=0.001, and P=0.001, respectively). Erythrocyte GSH-Px (39%), plasma GSH-Px (24%) and erythrocyte CuZn-SOD activities (32%) were significantly lower than those of the control group (P=0.001, P=0.002, P=0.001, respectively). In conclusion, our results demonstrate that the activity of antioxidant enzymes and plasma levels of Se, Zn and Mn levels were decreased in both homozygous and heterozygous subjects with leptin gene mutation. We suggest that both leptin and trace elements might be involved in the modulation of antioxidant defense system.
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PMID:Defective antioxidant defense system in patients with a human leptin gene mutation. 1096 32

In this study, we investigated the impact of ischemia-reperfusion on antioxidant enzyme activities and trace element concentrations. For this purpose, ischemia was initiated by clamping superior mesenteric artery of Wistar (albino) rats for 30 min, followed by reperfusion for 20 min. Immediately after reperfusion, blood samples were taken and examined for red cell copper-zinc superoxide dismutase (Cu-Zn-SOD), catalase (CAT), and glutathione peroxidase (GPx) activities spectrophotometrically and plasma zinc, copper, and magnesium concentrations by atomic absorption spectrophotometer. In the ischemia-reperfusion group, red cell Cu-Zn-SOD activity and plasma zinc and copper concentrations were increased significantly (p < 0.001) when compared to the control group; however, the increases in GPx activity and plasma magnesium concentration were not significant (p > 0.05). We also found a significant (p < 0.01) decrease in catalase activity. Free radicals released as a consequence of ischemia-reperfusion caused significant alterations in antioxidant enzymes and in the concentrations of trace elements.
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PMID:Antioxidant enzyme activities and trace element concentrations in ischemia-reperfusion. 1099 27

Excessive generation of reactive oxygen intermediates can induce changes in the cellular antioxidant defence system. In this study we examine the antioxidant enzyme status and the expression of fibrosis-related marker proteins in the Adriamycin model of chronic renal failure in the rat. Twenty weeks after Adriamycin treatment, rats have overt nephrotic syndrome and renal failure with development of tubulo-interstitial fibrosis and glomerulosclerosis. Lipids accumulate in blood and in both glomeruli and tubulo-interstitial tissue. Desmin and alpha-smooth muscle actin expression increases in glomeruli and in the tubulo-interstitial area. Renal cortex antioxidant enzyme activities are decreased 20 weeks after Adriamycin injection (to 41% for catalase, to 56% for total superoxide dismutase and to 69% for glutathione peroxidase). The mRNA levels of catalase, Cu/Zn-superoxide dismutase and glutathione peroxidase-1 evaluated by Northern blot are decreased by more than 50% for catalase, Cu/Zn-superoxide dismutase and glutathione peroxidase-1. We conclude that in the rat Adriamycin-induced model of chronic renal failure with fibrosis, the combination of decreased antioxidant enzyme status in renal cortex with high concentrations of lipids in blood and renal tissue facilitates oxidative damage. Development of fibrosis is paralleled by increased expression of desmin and alpha-smooth muscle actin.
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PMID:Renal antioxidant enzymes and fibrosis-related markers in the rat adriamycin model. 1101 87

The mechanism for copper loading of the antioxidant enzyme copper, zinc superoxide dismutase (SOD1) by its partner metallochaperone protein is not well understood. Here we show the human copper chaperone for Cu,Zn-SOD1 (hCCS) activates either human or yeast enzymes in vitro by direct protein to protein transfer of the copper cofactor. Interestingly, when denatured with organic solvents, the apo-form of human SOD1 cannot be reactivated by added copper ion alone, suggesting an additional function of hCCS such as facilitation of an active folded state of the enzyme. While hCCS can bind several copper ions, metal binding studies in the presence of excess copper scavengers that mimic the intracellular chelation capacity indicate a limiting stoichiometry of one copper and one zinc per hCCS monomer. This protein is active and unlike the yeast protein, is a homodimer regardless of copper occupancy. Matrix-assisted laser desorption ionization-mass spectrometry and metal binding studies suggest that Cu(I) is bound by residues from the first and third domains and no bound copper is detected for the second domain of hCCS in either the full-length or truncated forms of the protein. Copper-induced conformational changes in the essential C-terminal peptide of hCCS are consistent with a "pivot, insert, and release" mechanism that is similar to one proposed for the well characterized metal handling enzyme, mercuric ion reductase.
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PMID:Mechanism of Cu,Zn-superoxide dismutase activation by the human metallochaperone hCCS. 1101 45

A human Cu,Zn-superoxide dismutase (Cu,Zn-SOD) gene was fused with a gene fragment encoding the nine amino acid transactivator of transcription (Tat) protein transduction domain (RKKRRQRRR) of HIV-1 in a bacterial expression vector to produce a genetic in-frame Tat-SOD fusion protein. The expressed and purified Tat-SOD fusion protein in Escherichia coli can enter HeLa cells in a time- and dose-dependent manner when added exogenously in a culture media. Denatured Tat-SOD protein was transduced much more efficiently into cells than were native proteins. Once inside the cells, transduced Tat-SOD protein was enzymatically active and stable for 24 h. The cell viability of HeLa cells treated with paraquat, an intracellular superoxide anion generator, was increased by transduced Tat-SOD. These lines of results suggest that the transduction of Tat-SOD fusion protein may be one of the ways to replenish the Cu,Zn-SOD in the various disorders related to this antioxidant enzyme.
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PMID:Transduction of Cu,Zn-superoxide dismutase mediated by an HIV-1 Tat protein basic domain into mammalian cells. 1109 60

Due to the role of oxygen free radicals in trophoblast cell differentiation, we used the in vitro model of villous cytotrophoblast differentiation into the syncytiotrophoblast to investigate the modulation of the key antioxidant enzyme copper/zinc superoxide dismutase (SOD-1) in the human trophoblast during pregnancy. Cytotrophoblast cells were isolated from first-trimester and term placentae. SOD-1 mRNA levels were determined using real-time quantitative polymerase chain reaction, protein levels were determined by immunoblotting with a specific monoclonal antibody, and oxidoreductase activity was measured during syncytiotrophoblast formation in vitro. Interestingly, SOD-1 protein levels fell significantly (P< 0.001) during syncytiotrophoblast formation but no corresponding change in enzyme activity was observed. This apparent discrepancy may be related to different amounts of SOD-1 co-factor in the two cell types. Indeed the level of copper was significantly higher (P< 0.05) in syncytiotrophoblast as compared with cytotrophoblast. SOD-1 mRNA levels remained stable during cytotrophoblast differentiation. SOD-1 expression and activity were similar in cytotrophoblast cells isolated from first-trimester and term placentae, and in the differentiated syncytiotrophoblast in vitro. These results underline the need to determine SOD-1 protein expression and activity simultaneously in order to gain a better knowledge of its role in human trophoblast cell differentiation.
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PMID:Modulation of copper/zinc superoxide dismutase expression and activity with in vitro differentiation of human villous cytotrophoblasts. 1109 26

Manganese superoxide dismutase (MnSOD), an inductive antioxidant enzyme, can protect cells from oxidative injury to the mitochondria. The elevation of MnSOD activity in cells can effectively prevent many diseases associated with oxidative stress. Polysaccharide Krestin (PSK), a kind of protein-bound polysaccharide extracted from Coriolus versicolor, is used as an immune response modifier in anti-tumor therapy. We have previously found that PSK could alleviate the oxidative injury that oxidized low density lipoprotein (Ox-LDL) brought to monocytes/macrophages, and therefore had some preventive or therapeutic effect on atherosclerosis. In order to find out if the effects of PSK were associated with the alteration ofantioxidant enzymes, we investigated its effect on MnSOD activity and gene expression in mouse peritoneal macrophages. The results showed that PSK could enhance SOD activity and increase the contents ofMnSOD mRNA in mouse peritoneal macrophages. Furthermore, the induction of MnSOD by PSK could be blocked by cycloheximide and actinomycin D.
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PMID:Polysaccharide Krestin enhances manganese superoxide dismutase activity and mRNA expression in mouse peritoneal macrophages. 1115 46

The role of thyroid hormones in metabolic pathways are well known. However, their involvement in lipid peroxidation and antioxidant enzyme activities is not known. In this study, the in vivo injection of 6-propylthiouracil (6-PTU) did not alter the concentration of malondialdehyde (MDA) and conjugated dienes in liver. The administration of triiodothyronine (T3) or diiodothyronine (T2) increased the peroxidation rate in hypothyroid fish. However, in normal fish, only a high dose of T2 caused increased malondialdehyde (MDA) production, rather than T3. SOD activity was higher in T2-treated groups in both experiments. Glutathione peroxidase (GPx) activity was also high in hypothyroid fish treated with T2. In normal specimens, injections of T3 and T2 had no effect on GPx activity. Glutathione reductase (GR) activity was not altered by hypothyroidism while T3 (1 microg) and T2 (1 microg) increased it. Glutathione content was low in 6-PTU treated fish and high in both T3- and T2-treated groups. Thus it can be concluded that not only T3 but also T2, formed by sequential monodeiodination of T4, is also effective in influencing lipid peroxidation and antioxidant enzyme activities in Anabas. Furthermore, hypothyroidism as well as hyperthyroidism affects lipid peroxidation in this teleost.
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PMID:Thyroid hormones regulate lipid peroxidation and antioxidant enzyme activities in Anabas testudineus (Bloch). 1116 15


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