Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P04179 (MnSOD)
 2,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To test directly whether mitochondrial Mn-superoxide dismutase (Mn-SOD) protects the lung epithelium from oxygen-induced injury, transgenic mice were produced in which the expression of human Mn-SOD mRNA was directly by transcriptional elements from the human pulmonary surfactant protein C gene. Human Mn-SOD mRNA was expressed in a lung-specific manner, and increased Mn-SOD protein was detected within mitochondria of alveolar Type II and nonciliated bronchiolar cells of the distal respiratory epithelium of the transgenic mice. The activity of Mn-SOD, but not catalase, CuZn-SOD, or glutathione peroxidase, was increased in lungs of transgenic mice. Transgenic mice were highly protected from lung injury during exposure to 95% oxygen, surviving significantly longer than nontransgenic littermates. Pulmonary pathology demonstrated decreased hemorrhage, hyaline membrane formation, and alveolar and interstitial edema in transgenic animals. The finding that increased Mn-SOD in distal respiratory epithelial cells confers protection from oxygen injury provides a basis for novel therapies to protect lung from injury during oxygen therapy of acute and chronic lung diseases.
 ...
PMID:Human Mn-superoxide dismutase in pulmonary epithelial cells of transgenic mice confers protection from oxygen injury. 138 28

Hypoxic injury of rat astroglial cells in primary culture initiates several modifications of their functional integrity. A significant decrease of the cellular oxygen consumption was observed in astrocytes submitted to a 15 h low oxygen pressure. The addition of almitrine (dialylamino-4',6'-triazinyl 2')-1-(bis-parafluorobenzydryl)-4-piperazine, a chemoreceptor agonist, restored almost completely the respiratory activity of the hypoxia treated cells. In order to test the hypothesis that oxygen free radical formation may contribute to the cellular damage resulting from ischemia, the activities of the following antioxidant enzymatic systems have been determined in the cultured astrocytes: Cu,Zn- and Mn-superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), glutathione reductase (GSH-RED), and catalase (CAT). Only a significant and specific decrease of the Mn-SOD activity was observed after the hypoxia-normoxia exposure. The other oxygen radical scavenging systems were not modified. The addition of almitrine antagonized the decrease of the Mn-SOD activity observed in the low oxygen pressure treated cells, but results clearly point-out the importance of oxygen radical production in the astroglial response after hypoxic injury. A beneficial effect of almitrine toward the observed alteration has been underlined. It is suggested that some mitochondrial alterations could be related to some aspects of the astroglial hypoxic stress.
 ...
PMID:Free radical scavenging systems of rat astroglial cells in primary culture: effects of anoxia and drug treatment. 140 63

The lung activity of the antioxidant enzymes (AOEs) copper, zinc superoxide dismutase (Cu,Zn SOD), catalase (CAT), and glutathione peroxidase (GP), but not manganese superoxide dismutase (Mn SOD), increases in rats during late gestation; the concentrations of Cu,Zn SOD mRNA and CAT mRNA also rise. During early postnatal exposure to > 95% O2, the lung activity of Cu,Zn SOD, CAT, and GP increases. We now show 1) the lung concentration of Mn SOD mRNA and GP mRNA does not increase in late gestation; 2) Mn SOD activity and the concentration of its mRNA and of GP mRNA increase during exposure of neonatal rats to > 95% O2; and 3) as previously shown for CAT mRNA, the increase in lung concentration of the mRNAs for Cu,Zn SOD, Mn SOD, and GP during early postnatal hyperoxia occurs with a 70-80% prolongation of the half-life of these mRNAs. We conclude that 1) in late gestation the level at which lung AOE gene expression is regulated differs among the enzymes, 2) the level at which lung AOE gene expression is regulated shortly after birth in response to > 95% O2 is uniform among the enzymes, and 3) the lung's AOE response to neonatal hyperoxia is not merely a step-up of its prenatal regulation but involves different regulatory mechanisms based on increased stability of AOE mRNAs.
 ...
PMID:Rat lung antioxidant enzymes: differences in perinatal gene expression and regulation. 141 24

Cellular protection against free radical reactions was measured in myocardium from ethanol-fed rats using ethanol administration in drinking water as a model of moderate alcohol intoxication. The activities of Cu,Zn-superoxide dismutase (SOD) and glutathione-S-transferase were higher in ethanol-fed rats than in controls, whereas Mn-SOD, catalase and glutathione peroxidase activities were not altered by ethanol treatment. Myocardial zinc was higher and selenium concentration lower in ethanol-fed rats than in controls. Ethanol consumption, which failed to modify the myocardial vitamin E level, did not result in increased lipid peroxidation, but decreased cytosolic and membraneous protein thiols.
 ...
PMID:Effects of chronic ethanol administration on free radical defence in rat myocardium. 141 73

We have previously shown that the polyethylene glycol conjugated superoxide dismutase (SOD), which has a plasma half-life of more than 24 h, protects the blood perfused rabbit heart against injury during ischaemia and reperfusion. However, the profile for the dose-dependency of protection was bell-shaped with loss of efficacy below 6000 and above 30,000 U/kg. In the present study, isolated rabbit hearts, perfused with blood from support rabbits, were subjected to a 2 min infusion with St Thomas' Hospital cardioplegic solution followed by 60 min of global ischaemia (37 degrees C) and 60 min of reperfusion. PEG-SOD was administered 1 h or 12-24 h before ischaemia. We assessed the effect of PEG-SOD on ischaemia- and reperfusion-induced changes in: (i) the tissue content of reduced glutathione (GSH), oxidized glutathione (GSSG) and malondialdehyde (MDA) and (ii) the activity of CuZn-SOD, Mn-SOD and glutathione peroxidase and reductase (GPD and GRD). Ischaemia and reperfusion reduced tissue GSH content by 70% and increased GSSG content by 400% (from their fresh aerobic values of 13.1.9 and 0.09 +/- 0.01 nmol/mg protein, respectively). PEG-SOD, given intravenously at various doses to donor and support rabbits 1 h or 12-24 h before ischaemia, protected against these changes with a bell-shaped dose-response relationship. Thus, with 0, 3000, 6000, 12,000, 30,000 and 60,000 U/kg, GSH content was 4.1 +/- 0.4, 4.8 +/- 0.4, 8.5 +/- 0.5, 12.3 +/- 1.6, 12.3 +/- 1.6 and 5.0 +/- 0.5 nmol/mg protein in the 1 h pretreatment group and 4.1 +/- 0.4, 4.2 +/- 0.5, 10.4 +/- 1.5, 11.2 +/- 1.1, 11.4 +/- 0.7 and 4.7 +/- 0.6 nmol/mg protein in the 12-24 h pretreatment group (means +/- S.E.M.). For GSSG the corresponding values were 0.36 +/- 0.04, 0.34 +/- 0.03, 0.12 +/- 0.01, 0.12 +/- 0.01, 0.11 +/- 0.01 and 0.41 +/- 0.03 nmol/mg protein for the 1 h group and 0.36 +/- 0.04, 0.35 +/- 0.02, 0.15 +/- 0.01, 0.12 +/- 0.01, 0.11 +/- 0.01 and 0.34 +/- 0.02 nmol/mg protein for the 12-24 h group. Ischaemia and reperfusion had no effect on tissue MDA content or CuZn-SOD, GDP and GRD activity, and in general, PEG-SOD also lacked significant effect on any of these variables at any dose studied. However, Mn-SOD activity was severely reduced by ischaemia and reperfusion (from 42 +/- 7 U/mg protein in fresh aerobic controls to 6 +/- 1 U/mg protein at the end of reperfusion).(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:PEG-SOD and myocardial antioxidant status during ischaemia and reperfusion: dose-response studies in the isolated blood perfused rabbit heart. 143 18

Enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were determined in the liver as well as several specific brain regions of young and old Fischer-344 rats of both sexes. In the liver of male rats, activities of CAT as well as Mn-SOD were lower, while activities of Cu Zn-SOD were higher in old (30-month-old) rats than in young (7-month-old) ones. Activities of total SOD as well as GSH Px were comparable for young and old male rat livers. In contrast to male rats, in female rat livers, activities of CAT were significantly higher in old (28-months-old) rats, while activities of Mn-SOD were slightly (but significantly) higher in old rat livers. In old male rats, activities of Mn-SOD were significantly higher than in young males in several specific regions of the brain (the substantia nigra (s. nigra), striatum, hippocampus) but lower in the cerebellum. In particular, SOD activities in s. nigra, striatum and hippocampus in old male rats were several fold higher than corresponding values in young male rats. Activities of Cu Zn-SOD were generally unchanged with age. Activities of CAT as well as GSH-Px (both Se-dependent and non-Se-dependent forms) were also relatively unaffected by age. In female rat brains, activities of Mn-SOD as well as those of others all remained mostly unaffected by aging, although there was a general tendency of slightly higher activities in most cerebral regions for Mn-SOD in old female rats. Thus, age-related changes of these antioxidant enzymes in the liver and brain are markedly sex dependent and some enzyme activities (such as CAT in the liver) change in an opposite direction with age. Changes of Mn-SOD in the brain were markedly region-specific in male rats. Results suggest that the significance of the changes of these antioxidant enzyme activities during aging needs to be carefully interpreted, taking into consideration the fact that changes are markedly variable depending on sex as well as the organs and brain regions examined.
 ...
PMID:Age-related changes in antioxidant enzyme activities are region and organ, as well as sex, selective in the rat. 143 48

Recent studies have demonstrated that intracolonic administration of trinitrobenzenesulfonic acid (TNB) dissolved in ethanol produces chronic colitis in rats, and that this model shares many features of human inflammatory bowel disease (IBD), particularly Crohn's disease. We investigated the role of free radicals in the pathogenesis of this colitis model. In the early stage of this colitis, antioxidant enzymes (such as superoxide dismutase, glutathione peroxidase) and an antioxidant, alpha-tocopherol, were significantly decreased with the severity of colonic damage. Mn-SOD at a dose of 50000 U/kg attenuated this colitis when preadministered subcutaneously one hour before the induction of colitis. These results suggest that oxygen-derived free radicals may play an important role in this colitis.
 ...
PMID:Possible role of free radicals in the chronic inflammation of the gut. 145 May 97

An in vitro model of alveolar epithelial oxidant injury was developed based on exposure to hyperoxia of cultured guinea pig type II pneumocytes using a biphasic cell culture system in aerobiosis. The present study investigates the roles of intracellular antioxidant enzymes and of glutathione in providing protection against hyperoxia. A 2-day type II cell culture in normoxia was associated with a significant decrease in protein, catalase, and Cu-Zn SOD cell content, whereas ATP cell content, Mn-SOD, and glutathione peroxidase (GPx) activities did not change and glutathione cell content significantly increased. Exposure of type II cells to hyperoxia did not induce significant changes in cell content in protein, SOD, catalase, GPx, or glutathione cell content when compared to control cells (exposed to normoxia). With ATP cell content expressed as a cell injury index (CII), type II cell injury was found to increase with increasing O2 concentrations. Indeed, a 2-day 50% O2 and 95% O2 exposure resulted in a CII of -7.5 +/- 6.2% and 17.9 +/- 5.9%, respectively, LDH release by type II cells was not significantly increased after hypoxic exposure. Cell injury effects of hyperoxia did not correlate with the endogenous antioxidant enzyme activities (SOD, Mn-SOD, catalase). In marked contrast, there was a significant correlation between the CII and total glutathione content of type II cells (p < .01). This correlation was largely due to the close relationship between CII and reduced glutathione. Hyperoxic induced cell injury (as demonstrated by CII > 0) was clearly associated with significantly lower intracellular glutathione level when compared to experiments without hyperoxia induced cell injury (CII < 0). In addition, in the presence of buthionine sulfoximine (BSO), the ability of type II cells to synthetize new glutathione was severely impaired, whereas ATP cell content and cell antioxidant enzyme activities did not change. As a consequence, the reduction of intracellular glutathione significantly increased the susceptibility of cells to hyperoxia injury (p < .05). The results strongly support the hypothesis that the regulation of glutathione levels is an important mechanism in protecting hyperoxia-induced type II cell injury.
 ...
PMID:In vitro effects of hyperoxia on alveolar type II pneumocytes: inhibition of glutathione synthesis increases hyperoxic cell injury. 146 13

We have studied the pattern of enzymatic antioxidant activities (Cu-Zn superoxide dismutase = SOD, Mn-SOD and glutathione peroxidase = GSH-Px) in brain cortex of rats subjected to experimental induction of subarachnoid hemorrhage (SAH), in order to discuss the modifications of antioxidant systems in relation to the development of lipid peroxidative processes occurring in brain cortex. Lipid peroxidation (quantified as TBRAs content) did not show significantly changes, when sham-operated and SAH rats were compared; meanwhile at 1 hour TBARs content shows an increasing trend both in sham-operated and hemorrhagic rats. The release of leukotriene C4, the major lipoxygenase metabolite, is significantly enhanced at 1, 6 and 48 hours after SAH induction. Cu-Zn SOD activity is significantly reduced at 6 and 48 hours after SAH induction; Mn-SOD activity is significantly affected at 1, 6 and 48 hours after the hemorrhage. GSH-Px activity is significantly reduced only in the late phase (48 hours) after SAH. The results of the present study suggests that: (a) in brain compartment a significant reduction of antioxidant enzymatic activities is related to the increasing trend of enzymatic lipid peroxidation; (b) antioxidant activities showed specific time-dependent modifications: Cu-Zn and Mn SOD activities, which are specific scavengers of superoxide radicals, showed an early impairment, while GSH-Px activity is significantly reduced only after 48 hours; (c) the enhancement of enzymatic lipid peroxidation via the lipoxygenase pathway seems to play a primary role in brain response to SAH. These results should be considered the rationale for pharmacological treatment with antioxidant compounds for brain protection against detrimental effects of subarachnoid hemorrhage.
 ...
PMID:Brain damage following subarachnoid hemorrhage: the imbalance between anti-oxidant systems and lipid peroxidative processes. 150 Sep 55

The developmental expression of catalase, superoxide dismutase (both Mn-SOD and Cu/Zn-SOD) and glutathione peroxide activities were determined in human lung and liver from 10 wk gestation to 3 months following birth. Pulmonary superoxide dismutase and glutathione peroxidase activities did not change appreciably over this period. Catalase activity however, increased from 20.9 +/- 7.8 U/mg protein (n = 29) at 11-20 wk gestation to 73 +/- 27.5 U/mg protein (n = 30; P less than 0.001) following normal delivery (41-60 wk post-conceptual age). Lung catalase activity was temporally associated with the late gestational increase in the fractional content of lung DPPC (r = 0.79, P less than 0.01). In contrast with the lung, liver total superoxide dismutase activity increased from 2.5 +/- 0.6 U/mg protein (n = 27) between 11 and 20 wk gestation to 9.4 +/- 4.4 U/mg protein after term (n = 22; P less than 0.001). Since hepatic Mn-superoxide dismutase activity did not change over this period, the increase was attributed to elevated expression of Cu/Zn-superoxide dismutase. Liver glutathione peroxidase activities remained relatively constant during the same period, while hepatic catalase activity, although constant during gestation (60 +/- 15.6 microU/mg protein), increased significantly following birth (99.7 +/- 33.0 microU/mg protein; P less than 0.001). These results demonstrate that the developmental expression of antioxidant enzymes differs between tissues and that, unlike many commonly used laboratory species, only increased expression of catalase activity is associated with human lung development.
 ...
PMID:Catalase, superoxide dismutase and glutathione peroxidase activities of lung and liver during human development. 152 75


1 2 3 4 5 6 7 8 9 10 Next >>