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)

Dominant mutations in the copper/zinc superoxide dismutase (SOD1) gene have been observed in 15-20% of familial amyotrophic lateral sclerosis (FALS) cases. The mechanism by which SOD1 mutations result in motor neuron degeneration in FALS mice partly involves oxidative damage and an increased peroxidase activity of the mutant SOD1. A new therapeutic approach designed to eliminate the substrate of this peroxidase activity was examined in two lines of transgenic mice expressing the FALS-linked mutation glycine to alanine (G93A). We investigated the ability of putrescine-modified catalase (PUT-CAT), an antioxidant enzyme that removes hydrogen peroxide and has increased permeability at the blood-brain barrier, to modify the time course of the SOD1 mutation-induced motor neuron disease in these FALS mice. Continuous, subcutaneous administration of PUT-CAT significantly delayed the age at which onset of clinical disease occurred (indicated by loss of splay and/or tremors of hindlimbs) in a high-expressor line of FALS transgenic mice. Intraperitoneal injection of PUT-CAT given two times per week also significantly delayed the onset of clinical disease in a low-expressor line of FALS mice. PUT-CAT also significantly delayed the age at which clinical weakness developed (quantified by measuring the shortening of stride length) in both lines of FALS animals. No significant changes were observed in the survival times of the high-expressor FALS mice in any of the treatment groups. However, a trend toward a prolongation of survival was observed in the PUT-CAT-treated low-expressor FALS mice. These results support the role of free radical-mediated damage in the cascade of events leading to motor neurodegeneration in FALS and indicate that PUT-CAT interacts with a critical step in this cascade to delay the onset of clinical disease as well as the development of clinical weakness in FALS transgenic mice.
Exp Neurol 1999 Sep
PMID:Therapeutic benefits of putrescine-modified catalase in a transgenic mouse model of familial amyotrophic lateral sclerosis. 1048 88

The absence of the antioxidant enzyme Cu,Zn-superoxide dismutase (SOD1) is shown here to cause vacuolar fragmentation in Saccharomyces cerevisiae. Wild-type yeast have 1-3 large vacuoles whereas the sod1Delta yeast have as many as 50 smaller vacuoles. Evidence that this fragmentation is oxygen-mediated includes the findings that aerobically (but not anaerobically) grown sod1Delta yeast exhibit aberrant vacuoles and genetic suppressors of other oxygen-dependent sod1 null phenotypes rescue the vacuole defect. Surprisingly, iron also is implicated in the fragmentation process as iron addition exacerbates the sod1Delta vacuole defect while iron starvation ameliorates it. Because the vacuole is reported to be a site of iron storage and iron reacts avidly with reactive oxygen species to generate toxic side products, we propose that vacuole damage in sod1Delta cells arises from an elevation of iron-mediated oxidation within the vacuole or from elevated pools of "free" iron that may bind nonproductively to vacuolar ligands. Furthermore, additional pleiotropic phenotypes of sod1Delta cells (including increased sensitivity to pH, nutrient deprivation, and metals) may be secondary to vacuolar compromise. Our findings support the hypothesis that oxidative stress alters cellular iron homeostasis which in turn increases oxidative damage. Thus, our findings may have medical relevance as both oxidative stress and alterations in iron homeostasis have been implicated in diverse human disease processes. Our findings suggest that strategies to decrease intracellular iron may significantly reduce oxidatively induced cellular damage.
J Biol Chem 1999 Sep 24
PMID:Oxidative stress and iron are implicated in fragmenting vacuoles of Saccharomyces cerevisiae lacking Cu,Zn-superoxide dismutase. 1048 97

The effects of two oleic-acid-rich diets (containing olive oil, OO, and high-oleic-acid sunflower oil, HOSO) on plasma and liver lipid composition detoxification enzyme activities, were compared with those of a fish-oil (FO) diet and a control diet. Compared with the control diet, plasma and hepatic total triacylglycerol concentrations were increased in the animals fed on the HOSO and OO diets and decreased in those fed on the FO diet. The animals fed on FO showed the highest level of cholesterol in the liver and had lower plasma cholesterol concentrations when compared with those fed on the two oleic-acid-rich diets. In comparison with the animals fed on the diets enriched in oleic acid, the FO group showed higher hepatic levels of polyunsaturated fatty acids of the n-3 series and lower levels of fatty acids of the n-6 series. Livers of FO-fed rats, compared with those of OO- and HOSO-fed rats showed: (1) significantly higher activities of catalase (EC 1.11.1.6) glutathione peroxidase (EC 1.11.1.9) and Cu/Zn superoxide dismutase (EC 1.15.1.1); (2) no differences in the NADPH-cytochrome c reductase (EC 1.6.99.3) activity. The HOSO diet had a similar effect on liver antioxidant enzyme activities as the OO diet. In conclusion, it appears that changes in the liver fatty acid composition due mainly to n-3 lipids may enhance the efficiency of the antioxidant defence system. The two monounsaturated fatty acids oils studied (OO and HOSO), with the same high content of oleic acid but different contents of natural antioxidants, had similar effects on the antioxidant enzyme activities measured.
Br J Nutr 1999 Sep
PMID:Effects of dietary fats (fish, olive and high-oleic-acid sunflower oils) on lipid composition and antioxidant enzymes in rat liver. 1065 70

Increased oxidative stress resulting from free radical damage to cellular function is associated with a number of neurodegenerative diseases, in particular with Alzheimer's disease (AD). The deposition of amyloid beta-peptide (Abeta), the major pathological hallmark for AD, has been suggested as the central disease-causing and disease-promoting event for the disease, and the pathological role of Abeta was partially mediated by oxidative stress. Here we compared the effects of huperzine A (HupA) and tacrine, two acetylcholinesterase (AChE) inhibitors available for AD, on Abeta-induced cell lesion, level of lipid peroxidation, and antioxidant enzyme activities in rat PC12 and primary cultured cortical neurons. Following exposure of both cells to different concentrations of an active fragment of Abeta, a marked reduction in cell survival and activities of glutathione peroxidase (GSH-Px) and catalase (CAT), as well as increased production of malondialdehyde (MDA) and superoxide dismutase (SOD), were observed. Pretreatment of the cells with HupA or tacrine (0.1-10 microM) prior to Abeta exposure significantly elevated the cell survival and GSH-Px and CAT activities and decreased the level of MDA. Both drugs have similar protection against Abeta insult. Our results indicate that HupA and tacrine exert neuroprotective effects against Abeta toxicity, which might be of importance and might contribute to their clinical efficacy for the treatment of AD.
J Neurosci Res 2000 Sep 01
PMID:Huperzine A and tacrine attenuate beta-amyloid peptide-induced oxidative injury. 1095 26

Because of their antioxidant properties, carotenoids may have beneficial effects in preventing cancer and cardiovascular disease. However, in humans consuming carotenoid-rich vegetables, data concerning the antioxidant effects of carotenoids are rather scarce. A human intervention trial was conducted, therefore, to determine whether a moderately increased consumption of carotenoid-rich vegetables would influence the antioxidant status in 23 healthy men. This short-term feeding study lasted 8 wk during which the men consumed a low carotenoid diet. A 2-wk low carotenoid period was followed by daily consumption of 330 mL tomato juice, then by 330 mL carrot juice and then by 10 g of spinach powder, each for 2 wk. Antioxidant status [water-soluble antioxidants in serum, ferric reducing ability of plasma (FRAP) and antioxidant enzyme activities] and lipid peroxidation (plasma malondialdehyde and ex vivo oxidation of LDL) were determined. In a subgroup of 10 men, lipoprotein carotenoids were measured. The consumption of carotenoid-rich vegetables significantly increased selected carotenoids in lipoproteins but had only minor effects on their relative distribution pattern. Tomato juice consumption reduced plasma thiobarbituric acid reactive substances (TBARS) by 12% (P: < 0.05) and lipoprotein oxidizability in terms of an increased lag time (18%, P: < 0.05). Carrot juice and spinach powder had no effect on lipid peroxidation. Water-soluble antioxidants, FRAP, glutathione peroxidase and reductase activities did not change during any study period. In evaluating the low carotenoid diet, we conclude that the additional consumption of carotenoid-rich vegetable products enhanced lipoprotein carotenoid concentrations, but only tomato juice reduced LDL oxidation in healthy men.
J Nutr 2000 Sep
PMID:Moderate intervention with carotenoid-rich vegetable products reduces lipid peroxidation in men. 1095 13

Diesel exhaust particles (DEP) contain organic chemicals that contribute to the adverse health effects of inhaled particulate matter. Because DEP induce oxidative stress in the lung and in macrophages, effective antioxidant defenses are required. One type of defense is through the expression of the antioxidant enzyme, heme oxygenase I (HO-1). HO-1 as well as phase II detoxifying enzymes are induced via antioxidant response elements (ARE) in their promoters of that gene. We show that a crude DEP total extract, aromatic and polar DEP fractions, a benzo(a)pyrene quinone, and a phenolic antioxidant induce HO-1 expression in RAW264.7 cells in an ARE-dependent manner. N-acetyl cysteine and the flavonoid, luteolin, inhibited HO-1 protein expression. We also demonstrate that the same stimuli induce HO-1 mRNA expression in parallel with the activation of the SX2 enhancer of that gene. Mutation of the ARE core, but not the overlapping AP-1 binding sequence, disrupted SX2 activation. Finally, we show that biological agents, such as oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine, could also induce HO-1 expression via an ARE-dependent mechanism. Prior induction of HO-1 expression, using cobalt-protoporphyrin, protected RAW264.7 cells against DEP-induced toxicity. Taken together, these data show that HO-1 plays an important role in cytoprotection against redox-active DEP chemicals, including quinones.
J Immunol 2000 Sep 15
PMID:Induction of heme oxygenase-1 expression in macrophages by diesel exhaust particle chemicals and quinones via the antioxidant-responsive element. 1097 58

A number of studies indicate that free radicals are involved in the neurodegeneration in Alzheimer's disease (AD). The present study was mainly conducted to examine the effect of Huperzine B on H(2)O(2) induced toxicity in rat pheochromocytoma line PC12 by measuring cell lesion, level of lipid peroxidation and antioxidant enzyme activities. Following a 30 min exposure of the cells to H(2)O(2) (150 microM), a marked decrease in cell survival, activities of glutathione peroxidase and catalase as well as increased production of malondialdehyde (MDA) were found. Pretreatment of the cells with huperzine B (10-100 microM) prior to H(2)O(2) exposure significantly elevated the cell survival, antioxidant enzyme activities and decreased the level of MDA. The above-mentioned neuroprotective effects are also observed with tacrine (1 microM), donepezil (10 microM) and galanthamine (10 microM), suggesting that the neuroprotective effects of cholinesterase inhibitor might partly contribute to the clinical efficacy in AD treatment.
Neurosci Lett 2000 Sep 29
PMID:Huperzine B, a novel acetylcholinesterase inhibitor, attenuates hydrogen peroxide induced injury in PC12 cells. 1099 45

Retina and pigment epithelium of eyes are prone to increased production of reactive oxygen species and are susceptible to oxidative damage. We studied antioxidant enzyme activities in eye tissues exposed to prolonged low intensity (2000 lx) and short-term high intensity light (50000 lx) of visible range. Both prolonged low intensity and short-term intensive light increased superoxide dismutase, glutathione peroxidase and catalase activities in the pigment epithelium of frogs' eyes, while the activity of these enzymes in the retina remained unchanged. Our results suggest that visible light may increase oxidative stress and cause compensatory up-regulation of antioxidant enzyme activities in frogs' eyes.
Pathophysiology 2000 Sep
PMID:Light exposure induces antioxidant enzyme activities in eye tissues of frogs. 1099 14

Reactive oxygen species play a critical role in inflammatory processes including rheumatoid disorders. Antioxidant therapy strategies have been postulated for the treatment of rheumatoid diseases. In this study, we investigated activities and therapeutic implications of antioxidant enzymes in rheumatoid disorders. Activities of antioxidant enzymes glutathione peroxidase, glutathione reductase and catalase were examined in the blood of rheumatic patients and healthy controls. Activity of catalase was decreased significantly, while activities of glutathione peroxidase and glutathione reductase remained unchanged. Thioredoxin reductase is an antioxidant enzyme having an important regulatory task of thiol redox status and intracellular signaling processes coupled with the glutathione system. We also observed that in liver mitochondrial calf thioredoxin reductase was inhibited by antirheumatic drug goldthioglucose in the manner similar to intracellular thioredoxin reductase. Furthermore, during the treatment by goldthioglucose, gold is accumulated in lysosomes of macrophages. Our results suggest that although antioxidant enzyme activities were down-regulated in rheumatoid patients, we can decrease ROS generation by macrophages via inhibition thioredoxin reductase by goldthioglucose.
Pathophysiology 2000 Sep
PMID:Antioxidant enzymes; possible mechanism of gold compound treatment in rheumatoid arthritis. 1099 15

Potassium dichromate was given to female Swiss mice (25 mg/kg per day) orally in water for 1-3 days. Brain homogenates were prepared to evaluate the occurrence of oxidative stress in this organ through the measurement of the antioxidant defense levels, and the extent of lipid peroxidation. In addition, mitochondrial fractions were isolated from brain homogenates to determine the production of reactive oxygen species in this subcellular fraction. The administration of potassium dichromate for 3 days caused increases of 72 and 74% in superoxide dismutase and catalase activities, respectively, in the homogenates. The treatment with this metal for 3 days increased brain homogenate chemiluminescence and thiobarbituric acid-reactive substances by 34 and 29%, respectively. The brain contents of the non-enzymatic antioxidants alpha-tocopherol and sulfhydryl groups decreased by 35 and 32%, respectively. Ascorbic acid levels were not modified by the administration of potassium dichromate. Finally, there was a significant increment in the mitochondrial production of oxidants in the brain of treated mice as compared with controls. These results suggest that chromium(VI) produces an increased formation of reactive oxygen species and brain lipid peroxidation. The increase in the antioxidant enzyme activities reflects an adaptive response against oxidative stress, while the reduction in the levels of non-enzymatic antioxidants might be due to their reaction with reactive oxygen species generated during the metabolism of chromium(VI).
Toxicology 2000 Sep 07
PMID:Chromium(VI) induces oxidative stress in the mouse brain. 1133 12


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