Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.15.1.1 (superoxide dismutase)
 58,858 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to elucidate the exact role of antioxidant enzyme activities such as superoxide dismutase (SOD) in the aging process of animals, we compared various enzyme activities in different brain regions and in the liver of young (6-8 mo) and old (28-30 mo) Fischer-344 (F-344) rats. While Mn-SOD activities were elevated 3-5-fold in specific brain regions such as hippocampus, striatum and substantia nigra in brains of old male rats compared with the young, in females both forms of SOD (Cu, Zn- and Mn-) enzyme activities remained essentially unchanged with aging. Continued subcutaneous infusion of deprenyl for 3 weeks caused a 2-3-fold increase in activities of both Cu Zn- and Mn-SOD and a 50-60% increase in CAT activities in striatum and substantia nigra but not in hippocampus, cerebellum or the liver. Further, long-term treatment of old male rats with deprenyl caused a significant increase in the remaining life expectancy from 24 months of age by 34%. In conclusion, activities of antioxidant enzymes in these regions examined do not show any uniform age-associated change, suggesting that changes in these enzyme activities do not have any specific role in the life span of rodents in general terms. In contrast, the results of our deprenyl study suggests the possibility that the protection of catecholaminergic neurons by an upregulation of SOD and CAT activities plays a significant role in the life span of animals.
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PMID:Upregulation of antioxidant enzyme activities by deprenyl. Implications for life span extension. 868 37

For evaluation of the effects of different free-radical scavengers on biochemical changes in lens-induced uveitis (LIU), ten male Wistar rats were sensitized for 8 weeks using bovine lens protein and Freund's adjuvant. The uveitis was induced by disruption of the lens capsule. One group of animals received superoxide dismutase and catalase (SOD/CAT); a second group of animals was treated with vitamin E. Lipid peroxides (LPO) of the retinal tissue and aqueous humor served as parameter of oxidative tissue damage. Glutathione (GSH/GSSG) of the aqueous humor was evaluated as a parameter of the tissue's redox state. For evaluation of the inflammatory response, myeloperoxidase activity (MPO) was determined in the iris/ciliary-body complex. SOD/CAT produced no improvement in the significantly (P < 0.05) elevated MPO and LPO values recorded for untreated control animals. Following vitamin E treatment the GSH/GSSG and LPO values in aqueous humor were markedly improved as compared with controls. Retinal LPO values were significantly (P < 0.05) reduced as compared with controls. No change in MPO levels was observed. The results demonstrate that enzymes such as SOD and CAT do not influence tissue damage at a significant level, whereas radical chain breakers such as vitamin E can do so. However, the inflammatory response itself is not reduced. To achieve global results, drugs are necessary that act on both free radicals produced by noninflammatory pathways and those originating from inflammation.
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PMID:Effects of different antioxidants on lens-induced uveitis. 885

The activities of antioxidant enzymes i.e. Cu, Zn-SOD, Mn-SOD, CAT, and GSH-Px in the normal brain and brain tumors, as well as the two varieties of SOD in the mitochondria were examined and correlated to the histopathological diagnosis and the degree of malignancy of tumors. It was found that these scavenging enzymes of oxygen free radicals were expressed with great regularity in brain tumors. Both Cu, Zn-SOD and Mn-SOD were decreased in descending order in meningiomas, low grade astrocytomas, high grade astrocytomas and medulloblastomas. Furthermore, the reduction of Mn-SOD in mitochondria was proportionate to that of the whole tissues. While in contrast to the SODs, the CAT levels were significantly increased in ascending order in high grade astrocytomas, low grade astrocytomas and meningiomas. GSH-Px increased in meningiomas but not in gliomas.
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PMID:Study of the antioxidant enzymes in human brain tumors. 885 16

To test the hypothesis that oxygen radicals play an important role in the nonvagal component of the noncholinergic bronchoconstriction in vivo, 37 guinea pigs weighing 329 +/- 8 g were randomly divided into five groups: group 1, vagotomy; group 2, vagotomy + CAT (catalase); group 3, vagotomy + SOD (superoxide dismutase); group 4, vagotomy + PBN (alpha-phenyl-N-tert-butyl nitrone); and group 5, capsaicin pretreatment. CAT, SOD, and PBN are antioxidants. Each animal was anesthetized, paralyzed, artificially ventilated, and pretreated with atropine and phenoxybenzamine. Immediately after acute capsaicin challenge, animals in group 1 exhibited decreases in maximal expiratory flow, dynamic respiratory compliance, and total lung capacity, as well as an increase in functional residual capacity, indicating noncholinergic airway constriction. The bronchoconstriction was significantly ameliorated by SOD and PBN, and it was almost abolished by capsaicin pretreatment. Thirty minutes after acute capsaicin challenge, there was a significant decrease in airway NEP activity and an increase in lung substance P level in group 1 but not in other groups. These results indicate that nonvagal component of noncholinergic bronchoconstriction is partially modulated by oxygen radicals.
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PMID:Oxygen radicals in the nonvagal component of noncholinergic airway constriction. 889 67

Superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6) and glutathione peroxidase (GSH-Px; EC 1.19.1.1) were assayed in erythrocytes from neonates over a range of gestational ages. Both SOD and CAT activities were found to increase, but GSH-Px to decline, with gestational age. Enzyme activities in the erythrocytes of 13 babies who had respiratory distress syndrome (RDS) were not significantly different from controls matched for gestational age, but four with bronchopulmonary dysplasia (BPD) were found to have lower SOD activity. The importance of SOD in the preparation for extrauterine life is substantiated.
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PMID:Erythrocyte enzymes decomposing reactive oxygen species and gestational age. 890 59

The effects of the N-formyl methionyl peptide, formyl-methionyl-leucyl phenylalanine (fMLF) on the lateral mobility of the complement receptor type 1 (CR1/CD35) in glass-adherent human neutrophils were investigated, using fluorescence recovery after photobleaching (FRAP) and confocal microscopy (CSLM). It was found that addition of 0.1-1 microM fMLF increased the diffusion constant (D) of CR1/CD35 to 167-228% of controls. No effect was observed on the receptor distribution or the mobile fraction of receptors. The effect of fMLF on the lateral diffusion of CR1/CD35 could be totally inhibited by addition of pertussis toxon (PD, 250 ng/ml) or of the free radical scavenger enzymes superoxide dismutase (SOD, 2000 U/ml) and catalase (CAT, 200 U/ml), added together the results show that oxidative metabolites produced by neutrophils in response to fMLF can modulate CR1/CD35 diffusion, and indicate a regulatory role for oxygen radicals in phagocytosis.
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PMID:The N-formyl methionyl peptide, formyl-methionyl-leucyl phenylalanine (fMLF) increases the lateral diffusion of complement receptor 1 (CR1/CD35) in human neutrophils; a causative role for oxidative metabolites? 891 29

The Cu/Zn superoxide dismutase (SOD1) is one of the key enzymes that protect cells against oxidative stress. It catalyzes the dismutation of superoxide radicals (O2-) to oxygen and hydrogen peroxide. To study the transcriptional regulation of the human Cu/Zn SOD gene, we began by analyzing the 1.5-kb upstream region of the gene (see Kim et al., 1994). The element from nucleotides (nt) -116 to -45 increased the transcriptional activity of Cu/Zn SOD. Analyses by DNase I footprinting and electrophoretic mobility shift assay (EMSA) showed that Sp1 binds to the region from nt -104 to -89 and C/EBP-related factors to the region from nt -64 to -55. Studies using two mutant versions of this promoter, in which the Sp1 and C/EBP-related factor binding sites were deleted, respectively, revealed that Sp1 and C/EBP-related factors activate the transcription of SOD1 gene. An Sp1 expression plasmid, pPacSp1, stimulated the SOD1-linked CAT expression. Cotransfection of the element from nt -116 to -45 with the C/EBP alpha expression vector, pMSV-C/EBP, increased the transcriptional activity of the Cu/Zn SOD in HepG2 cells, but barely in HeLa cells. Because Sp1 is a ubiquitously expressed transcriptional factor, the binding of Sp1 to the proximal upstream region of the Cu/Zn SOD might explain the expression of Cu/Zn SOD in a wide variety of cells.
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PMID:Sp1 and C/EBP-related factor regulate the transcription of human Cu/Zn SOD gene. 892 11

The defenses against the production of free radicals and reactive oxygen species (ROS) are to be found in plasma (ascorbate, urate, alpha tocopherol) and in erythrocytes (superoxide dismutase or SOD; catalase or CAT; glutathione peroxidase or GPx). In chronic renal failure, an increased lipid peroxidation and a reduced antioxidant activity seem to be present, but previous reports are conflicting. To clarify the peroxidative status and the defense mechanisms taking place in patients on dialysis, in 30 patients on dialysis (15 men, 15 women) and in 20 control subjects (10 men, 10 women), the following parameters were measured: plasma 4-hydroxinonenal (4-HNE) and erythrocyte reduced glutathione (GSH), SOD, GPx, and glucose-6-phosphate dehydrogenase (G-6-PD). Patients on dialysis, in comparison with control subjects, had 1) increased levels of 4-HNE (p < 0.001); 2) a significant increase in erythrocyte-GSH (p < 0.05); and 3) significant decreases in erythrocyte-SOD (p < 0.001), erythrocyte-G-6-PD (p < 0.005), and the erythrocyte-SOD/GPx ratio (p < 0.001). The dialysis procedure induced a certain reduction in plasma 4-HNE, an increase in erythrocyte-SOD activity, and an important consumption of erythrocyte-GSH, while the erythrocyte-SOD/GPx ratio changed. The current study supports the view that 1) erythrocytes act as small detoxifying packets; 2) in chronic renal failure, the antioxidant system is largely inadequate; and 3) in patients on dialysis, the antioxidant mechanism of erythrocytes in scavenging ROS is effectively exerted during dialysis but remains largely inadequate, as signs of lipid peroxidation persist with time.
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PMID:The role of erythrocytes in the deperoxidative processes in people on hemodialysis. 894 13

In this study, superoxide dismutase (SOD) and catalase activities were determinated in the erythrocytes (RBC) from patients with chronic renal failure. The study included healthy subjects (n = 7), patients on hemodialysis (HD) using polyacrylonitrile-type dialysis membrane (before and after HD) (n = 10), patients on HD using cuprophane-type dialysis membrane (before and after HD) (n = 6), and patients on continuous ambulatory peritoneal dialysis (CAPD) (n = 11). A significant decrease in SOD activity was found in HD groups using polyacrylonitrile- or cuprophane-type dialysis membrane. SOD activity was found to increase in patients undergoing CAPD. We have found that CAT activity is higher in all the CRF groups in respect to the control: with polyacrylonitrile-type dialysis membrane, with cuprophane-type dialysis membrane, and in CAPD treatment.
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PMID:Superoxide dismutase and catalase activities in patients undergoing hemodialysis and continuous ambulatory peritoneal dialysis. 894 28

The efficiency with which beta-carotene protects against oxidative stress in chicken embryo fibroblasts (CEF) at low O2 partial pressures was assessed. Primary cultures of CEF were grown at low O2 partial pressures and oxidatively stressed by exposure to paraquat (PQ). Activities of the antioxidant enzymes superoxide dismutase (EC 1.15.1.1; SOD), catalase (EC 1.11.1.6; CAT) and glutathione peroxidase (EC 1.11.1.9; GSH-Px) were measured as indices of oxidative stress. CEF incubated with 0.25-1.0 mM-PQ for 18 h exhibited increased SOD and CAT activities compared with non-PQ-treated control cells (P < 0.001). No cytotoxicity as indicated by lactate dehydrogenase (EC 1.1.1.27; LDH) release was observed at PQ concentrations below 2.0 mM. Incorporation of added beta-carotene into 0.25 mM-PQ-treated cells prevented the PQ-induced increases in SOD and CAT, and activities were similar to those seen in non-PQ-treated control cells. GSH-Px activity decreased relative to its control value on exposure to 0.25 mM-PQ and beta-carotene prevented this decrease in a dose-dependent manner. The proportion of LDH released from the CEF treated with beta-carotene remained below the control value of 2.5% at all times.
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PMID:Modulation of paraquat toxicity by beta-carotene at low oxygen partial pressure in chicken embryo fibroblasts. 905 36


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