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)

Polyclonal antisera to manganese and copper-zinc superoxide dismutases, catalase, glutathione peroxidase (GPx), and isozymes of glutathione S-transferase (liver and placental isolates, GST-L and GST-P, respectively) were used to localize these enzymes in normal rat lung by immunostaining. Light-microscopic results, using an immunoperoxidase technique, were expanded on by electron-microscopic immunogold localization. The findings were consistent with previous biochemical work. However, both GPx and GST-P were predominantly localized to extracellular connective tissue of the lung. These findings demonstrate the basal antioxidant enzyme phenotypes for parenchymal lung tissue at light- and electron-microscopic levels. Significant components of enzymatic defense to oxidant stress are heterogeneously distributed throughout rat lung tissue including both epithelial cell surfaces and the extracellular matrix.
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PMID:Immunolocalization of antioxidant enzymes and isozymes of glutathione S-transferase in normal rat lung. 128 3

Copper-zinc-superoxide dismutase (CuZn-SOD), a cytosolic antioxidant enzyme that is specific for scavenging superoxide radicals, is involved in neuroprotective mechanisms in brain injury following trauma and cerebral ischemia. Liposome-entrapped CuZn-SOD exhibit beneficial effects in vivo on cold-induced vasogenic edema and on blood-brain barrier disruption. The increased levels of edema and infarction following a focal cerebral ischemia also are decreased by the pretreatment of liposome-entrapped CuZn-SOD. The protective role of SOD on brain injury was further extended and confirmed in studies using transgenic mice overexpressing human CuZn-SOD. Our studies so far suggest that increased cerebral levels of SOD, either by means of external pharmacological application or by genetic manipulations, ameliorate brain edema and infarction induced by trauma and focal cerebral ischemia.
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PMID:Antioxidant-dependent amelioration of brain injury: role of CuZn-superoxide dismutase. 131 99

Influences of dietary selenium (Se) deficiency, physical training and an acute bout of exercise on myocardial antioxidant enzyme activity, lipid peroxidation and related biochemical properties were investigated in post-weanling male Sprague-Dawley rats. An experimental group was fed a diet containing less than 0.01 mg Se/kg and had free access to distilled water (Se-D), whereas control rats were supplemented with 0.5 mg Se/l in drinking water (Se-A). Se deficiency depleted heart mitochondrial and cytosolic Se-dependent glutathione peroxidase activity to 24 and 3%, respectively, of those in Se-A rats. Heart mitochondrial superoxide dismutase (Mn SOD) activity was 24% higher (p less than 0.05) in Se-D than in Se-A rats. Cytosolic (copper-zinc) SOD and catalase activities were not altered, whereas glutathione S-transferase activity was significantly decreased in Se-D (p less than 0.01). Myocardial antioxidant enzyme activities were not affected by either training or an acute exercise bout. Heart lipid peroxidation and activities of several enzymes in substrate metabolism were also unaffected by Se or exercise. It is concluded that rat heart has sufficient reserve of antioxidant enzyme capacity in coping with oxidative stress imposed by Se deficiency or exercise. The adaptation of Mn SOD may reveal its potential role in myocardial antioxidant defense.
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PMID:Antioxidant enzyme response to selenium deficiency in rat myocardium. 153 41

Copper,zinc superoxide dismutase (CuZnSOD), an antioxidant enzyme, is unique in requiring two essential metals for catalytic function. Yet, only one, copper, seems to regulate the expression of functional activity. Restricting dietary copper quickly impairs catalytic functioning of CuZnSOD in numerous tissues. Diets supplemented with copper or small amounts of CuCl2 administered intraperitoneally restore the enzyme activity in animals deprived of copper. Thus, CuZnSOD has been considered a good marker of copper status. A metal-free (apo) form of CuZnSOD could exist in tissues at all times, but especially when an animal is deprived of copper. Restoring CuZnSOD activity with copper permits elucidation of the pathway of copper incorporation into the enzyme. Ceruloplasmin and albumin transport copper to the enzyme in vitro. K562 cells, a human erythroleukemic cell line, can extract copper from ceruloplasmin and incorporate it into CuZnSOD. Ascorbic acid stimulates the transfer of 67Cu transfer from ceruloplasmin to the cells, and somewhat unexpectedly, appears to restrict the amount of transferred copper that becomes bound to the enzyme. Reactivation of CuZnSOD in healthy individuals has the potential of being a useful tool for assessing copper status. This approach has merit, but one must consider that the levels of apo-enzyme that prevail in tissue could be influenced by other metals.
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PMID:Copper as a cofactor and regulator of copper,zinc superoxide dismutase. 154 24

We used light microscopic immunohistochemistry to locate manganese superoxide dismutase, copper zinc superoxide dismutase, catalase, and glutathione-S-transferases in demineralized femora from rats of 4-14 weeks of age. Immunoblots confirmed the specificity of the polyclonal antibodies for the rat proteins of interest. Each of the enzymes exhibited a unique staining pattern. Copper-zinc superoxide dismutase was detected within some articular and epiphyseal chondrocytes of younger animals. Manganese superoxide dismutase was detected within some articular and epiphyseal chondrocytes, within some osteoprogenitor cells and osteoblasts, within many osteoclasts, and within some vascular smooth muscle cells. Catalase was identified within articular chondrocytes, epiphyseal chondrocytes, and osteocytes, whereas staining at the periphery of hypertrophic chondrocytes suggested extracellular and/or cell membrane-associted catalase. Glutathione-S-transferases were detected within and at the periphery of epiphyseal and articular chondrocytes and less prominently within cortical osteocytes. There were no major age-related changes in antioxidant enzyme distribution.
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PMID:Immunohistochemical identification of superoxide dismutases, catalase, and glutathione-S-transferases in rat femora. 157 Jul 63

Although the effects of cigarette smoking on a variety of diseases, from cancer through emphysema and cardiovascular illness are well documented, direct effects on the levels of macro- and micronutrients in the body are reported less frequently. In fact, imbalances in these nutrients may have a role in many of the pathological conditions attributed to smoking. Tobacco smoke contains numerous compounds emitted as gases and condensed tar particles, many of them being oxidants and prooxidants, capable of producing free radicals thus enhancing lipid peroxidation in biological membranes. Vitamin E, vitamin C, B-carotene and selenium are involved in the overall cellular anti-oxidant defense against deleterious effects of reactive oxygen species. Smoking has been shown to lower the level of vitamin C and B-carotene in plasma. Cadmium, naturally found in tobacco, decreases the bioavailability of selenium and acts antagonistically to zinc, a cofactor for the antioxidant enzyme, superoxide dismutase. Vitamin E, the principle lipid-soluble antioxidant, may be at suboptimal levels in tissues of smokers. In addition, tobacco constituents have been shown to reduce levels of several vitamins of the B-complex. Nutritional status in smokers may be further compromised by an inadequate diet. Data from the Second National Health and Nutrition Examination Survey indicates that smokers are less likely to consume fruits and vegetables, particularly those high in vitamin C and carotenes. Cessation of smoking is the obvious solution to ending cigarette-related problems. In the world as it is, however, the medical community should be responsible for making recommendations to lower the risk in smokers to tobacco related diseases. Nutritionists could have a role in this process. There exists a lively debate as to where levels of nutrients should be set. Additional vitamin C has already been recommended for smokers. Should other antioxidants also be increased? Arguments for the against are considered.
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PMID:Cigarette smoking-nutritional implications. 178 36

Pretreatment or "priming" with vincristine (VcR) has been documented to radioprotect animals from whole body irradiation by accelerating recovery of hematopoietic marrow. The mechanisms underlying this phenomenon are unclear, but the marked similarities between priming with VcR and with immune stimulants such as endotoxin and glucan have led to speculation that VcR may be inducing such radioprotective immunoregulators as interleukin 1 (IL-1) and tumor necrosis factor (TNF). The radioprotective ability of these cytokines, in turn, has been linked to an induction of the antioxidant enzyme manganese superoxide dismutase (Mn SOD). To establish whether priming with VcR is associated with induction of antioxidant enzymes, the activities of Mn SOD, copper-zinc (Cu-Zn) SOD, catalase (CAT), and glutathione peroxidase (GPX) were measured in the marrow of both LLca tumor-bearing and non-tumor-bearing mice given a priming dose of VcR. Results in non-tumor-bearing mice indicate that, similar to IL-1 and TNF administration, VcR treatment increases Mn-SOD activity, but not Cu-Zn SOD, CAT, or GPX activity. Furthermore, this increase occurs at the time VcR priming has been demonstrated previously to exhibit maximal radioprotection, suggesting that it may be contributing factor. However, VcR priming has been demonstrated to radioprotect both tumor-bearing and non-tumor-bearing animals, and no increase in Mn SOD activity (or the other enzymes monitored) was found in the tumor-bearing group. Rather, the presence of tumor significantly suppressed antioxidant enzyme activity. Collectively, the present data suggest that it is unlikely that increased antioxidant enzyme activity is directly involved in the VcR priming response.
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PMID:Marrow antioxidant enzyme activity in tumor-bearing and non-tumor-bearing mice following vincristine treatment. 199 2

Tissues from adult Syrian hamsters were studied with immunoperoxidase techniques using polyclonal antibodies to three antioxidant enzymes (copper, zinc and manganese forms of superoxide dismutase, and catalase). Tissues from labile organs, in which cell renewal is prominent (uterus, intestine, and transitional epithelium of the urinary tract), showed strong antioxidant enzyme immunostaining in differentiated cells but not in stem cells. In stable organs, in which cell renewal occurs at a high rate only in response to injury (kidney and adrenal), each cell type showed a specific pattern of antioxidant enzyme immunostaining. In permanent organs (brain and heart), antioxidant enzymes were regionally specific markers. Axons of the cerebellum showed more intense antioxidant enzyme staining than those of the cerebral cortex; in the heart, atria stained more intensely than ventricles. Germ cells of the testis resembled cell renewal systems in their antioxidant enzyme-immunostaining pattern: spermatogonia were negative, whereas spermatozoa were strongly positive. The tubules of the kidney showed no antioxidant enzyme immunostaining until after birth. Our results suggest that there is a prominent role for antioxidant enzymes in cell differentiation during development and cell renewal.
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PMID:Immunohistochemical localization of antioxidant enzymes in adult Syrian hamster tissues and during kidney development. 237 42

1. A number of dietary sugars are known to mediate the effects of copper deficiency. The effects of lactose (compared with sucrose) and a dietary Cu deficiency on hepatic and cardiac antioxidant enzyme activities and tissue mineral element status were investigated in the rat. 2. Groups (n 6) of male weanling Wistar rats were provided ad lib. with deionized water and diets containing sucrose (580 g/kg) or sucrose and lactose (387 g/kg and 193 g/kg respectively) with either control (12.0 mg/kg) or deficient (1.5 mg/kg) quantities of Cu for 77 d. 3. Animals consuming the low-Cu diets exhibited significantly decreased tissue Cu levels (P less than 0.01), hepatic and cardiac cytochrome c oxidase (EC 1.9.3.1, CCO) activities (P less than 0.01 and P less than 0.001 respectively) and hepatic Cu-zinc superoxide dismutase (EC 1.15.1.1, CuZnSOD) activity (P less than 0.05). The low-Cu diets also significantly decreased cardiac manganese superoxide dismutase (EC 1.15.1.1, MnSOD), catalase (EC 1.11.1.6) and glutathione peroxidase (EC 1.11.1.9, GSH-Px) activities (P less than 0.01, P less than 0.05 and P less than 0.001 respectively). 4. Hepatic Mn was significantly increased in both lactose-fed (P less than 0.001) and Cu-deficient (P less than 0.01) animals. These increases were unrelated to hepatic MnSOD activity. Cardiac Zn was significantly (P less than 0.01) increased in Cu-deficient animals. 5. Lactose feeding resulted in significantly increased cardiac CCO activity (P less than 0.001) but significantly decreased hepatic CuZnSOD (P less than 0.05), catalase (P less than 0.01) and GSH-Px (P less than 0.001) activities. 6. The activities of lactose dehydrogenase (EC 1.1.1.27, LDH) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49, G6PDH) were found to be significantly (P less than 0.05 and P less than 0.01 respectively) increased in Cu-deficient animals and G6PDH activity was significantly (P less than 0.01) decreased as a result of lactose consumption. 7. The observed changes in antioxidant enzyme activities associated with both Cu deficieny and lactose consumption may have important implications for the development of free radical mediated cell damage. However, no significant differences in either hepatic or cardiac levels of thiobarbituric acid reactive substances, a measure of lipid peroxidation, were found.
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PMID:Effects of copper deficiency on hepatic and cardiac antioxidant enzyme activities in lactose- and sucrose-fed rats. 253 51

Scavenging mechanisms for persistent free radicals were investigated using nitroxide-type radicals as model compounds. The free radical reducing activity of a) isolated thioredoxin reductase, a flavin containing oxidoreductase, b) skin homogenates, and c) the epidermis of hairless mice was studied by electron spin resonance spectroscopy. In all three systems, reduction rates of different classes of nitroxide free radicals exhibited the following order: oxazolidinoxy greater than piperidinoxy greater than dihydropyrroloxy. The main reductant for piperidinoxy radicals in mouse skin homogenate is ascorbic acid. Other reducing activities were stimulated by NAD(P)H and could be inhibited by N-ethyl maleimide, suggesting involvement of thiol-dependent processes. Mammalian thioredoxin, a competitive inhibitor of nitroxide reduction by thioredoxin reductase, significantly stimulates nitroxide scavenging in skin homogenate. Thioredoxin reductase did not significantly participate in nitroxide reduction in skin homogenates. At the surface of mouse epidermis a cationic dihydropyrroloxy nitroxide, which was stable in the presence of mammalian thioredoxin reductase was readily reduced. The epidermal reduction was inhibited by zinc, N-ethyl maleimide, and by heat (70 degrees C, 5 min). At least for mouse epidermis, reduction of a variety of nitroxides is a complex phenomenon involving enzymatic and nonenzymatic mechanisms and cannot be used as a specific assay for an enzyme, e.g., thioredoxin reductase. The study indicates the epidermis contains an effective antioxidant system that scavenges ascorbate-sensitive piperidinoxy nitroxides as well as more reducing radicals exemplified by dihydropyrroloxy nitroxides.
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PMID:Free radical reduction mechanisms in mouse epidermis skin homogenates. 238 May 82


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