Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.9.3.1 (cytochrome oxidase)
8,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

Neonatal, adult, and fetal rat lungs of 18, 20, and 22 d gestation from four to six litters were examined for cytochrome oxidase, glucose-6-phosphate dehydrogenase, catalase, glutathione peroxidase, copper-zinc and manganese superoxide dismutase activities. All results were corrected for the contribution of enzymes in blood that contaminate homogenates. Because lung protein/DNA ratios and body water change significantly with gestational age, enzyme activities were expressed as U/mg DNA. All activities were low in d 18 lung and increased with advancing gestational age. Only catalase and copper-zinc superoxide dismutase increased activity in response to air breathing, suggesting that maturation of the antioxidant enzyme system is virtually complete before delivery. Activities of glucose-6-phosphate dehydrogenase, catalase, glutathione peroxidase, and manganese superoxide dismutase were higher in neonatal than in adult lung.
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PMID:Pulmonary antioxidant enzyme maturation in the fetal and neonatal rat. I. Developmental profiles. 608 81

We have investigated the effect of doxorubicin (Adriamycin) on the yeast Saccharomyces cerevisiae. Drug treatment was found to be cytotoxic to wild-type strains, in a concentration-dependent manner, whereas a petite mutant lacking the cytochrome oxidase (EC 1.9.3.1) subunit IV gene was resistant to doxorubicin. Transformation of the doxorubicin-resistant mutant with a yeast in vivo expression vector harboring the cytochrome oxidase subunit IV gene restored both respiration and sensitivity to doxorubicin. Another petite strain, with a mutation in the mitochondrial adenine nucleotide translocator (pet9), did not display doxorubicin resistance. However, in contrast to the subunit IV mutant, it possesses a functional respiratory chain. We also compared the cytotoxic effect of doxorubicin with those of daunorubicin and mitoxantrone in yeast. We found comparable levels of cytotoxicity for doxorubicin and daunorubicin, which were significantly greater than that for mitoxantrone. Finally, we constructed a yeast strain that overexpresses manganese superoxide dismutase (EC 1.15.1.1), an antioxidant enzyme present in mitochondria. Overexpression of manganese superoxide dismutase protected significantly against doxorubicin and daunorubicin cytotoxicity but only slightly against mitoxantrone cytotoxicity. Collectively, our results provide direct in vivo evidence that superoxide radicals participate in doxorubicin- and daunorubicin-induced cytotoxicity in yeast. Furthermore, these results indicate that mitochondrial respiration is a crucial factor in anthracycline, and perhaps mitoxantrone, cytotoxicity in yeast.
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PMID:Doxorubicin, daunorubicin, and mitoxantrone cytotoxicity in yeast. 780 47

Human blood mononuclear cells exposed to visible light increase their antioxidant enzyme (superoxide dismutase, catalase, and glutathione peroxidase) and DT-diaphorase activities. The activities of CuZn-superoxide dismutase (3.70 +/- 0.25 U/mg protein), catalase (4.60 +/- 0.39 U/mg protein), and DT-diaphorase (1.40 +/- 0.11 mumol DCPIP/min.mg protein) increased 1.5-fold when mononuclear cells were exposed at 38 W/m2 for 4 h. Se-containing glutathione peroxidase activity (6.76 +/- 0.21 mU/mg protein) increased 1.3 times after 3 h of exposure to 38 W/m2. Conversely, Mn-superoxide dismutase (2.20 +/- 0.20 U/mg protein), succinate dehydrogenase (0.86 +/- 0.04 mumol DCPIP/min.mg protein), and cytochrome oxidase (0.54 +/- 0.04 min-1 (k')/mg protein) activities remained constant during this period of exposure. The treatment of cells with cycloheximide prevented the response triggered by light exposure. These results introduce new insight to the adaptive response of human cells to light stress suggesting that: (a) the response observed might be ascribed to synthesis of stress proteins rather than to activation of a preexisting pool, and (b) that DT-diaphorase and CuZn-superoxide dismutase may operate biologically in a concerted fashion resulting in antioxidant activity.
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PMID:Induction of antioxidant enzymes and DT-diaphorase in human blood mononuclear cells by light stress. 837 61

Cu has long been known to influence immune responses. An in vitro model system was established in which human myeloid (HL-60), B-lymphoid (Raji) and T-lymphoid (Molt-3) cell lines could be grown in culture media of varying Cu levels. Initially Cu was removed from the medium by dialysis of fetal calf serum against a metal-ion chelator, minor depletion of other trace metals being obviated by repletion with appropriate metal salts. The growth rate of HL-60 was significantly (P < 0.05) inhibited by 72 h Cu depletion. Molt-3 cells required a longer period, up to 144 h, in Cu-depleted medium before growth was impaired. Raji-cell growth was not affected. These results confirmed clinical observations that T-cell functions were more sensitive to Cu deprivation than B cells. Analysis of intracellular metal levels in Molt-3 cells showed that Cu levels had been significantly lowered (P < 0.05) although Ca2+ levels were raised. Intracellular activity of the antioxidant enzyme superoxide dismutase (EC 1.15.1.1) was significantly impaired (P < 0.05) in Molt-3 cells grown in Cu-depleted medium. Activity of the mitochondrial enzyme cytochrome c oxidase (EC 1.9.3.1) was also significantly impaired (P < 0.05) by Cu depletion. Each of these findings indicates an increase in the potential for cellular damage by reduced antioxidant activity, impairment of normal mitochondrial activity and excessive Ca2+ influx. A major consequence of the type of damage occurring under these circumstances is membrane disruption. This was confirmed by scanning electron microscopy of Molt-3 cells grown under varying Cu levels.
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PMID:The effects of copper deficiency on human lymphoid and myeloid cells: an in vitro model. 878 94

Human blood mononuclear cells exposed to UVB radiation develop increased antioxidant enzyme activities. Catalase (5.50 +/- 0.65 pmol (mg protein)-1), CuZn-superoxide dismutase (16.7 +/- 2.1 pmol (mg protein)-1), Mn-superoxide dismutase (11.3 +/- 1.7 pmol (mg protein)-1), Se-dependent glutathione peroxidase (13.2 +/- 1.5 mU (mg protein)-1) and Se-independent glutathione peroxidase (3.30 +/- 0.52 mU (mg protein)-1) activities increase by 1.3-1.5-fold from the control activities after exposure to 0.3 W m-2 of 280-315 nm light for 15 min and a 3 h dark incubation period. DT-diaphorase activity (2.86 +/- 0.21 mumol DCPIP min-1 (mg protein)-1) increases threefold from the indicated control values. In contrast, cytochrome oxidase (0.36 +/- 0.04 min-1 (k') (mg protein)-1) and succinate dehydrogenase (3.06 +/- 0.25 mumol DCPIP min-1 (mg protein)-1) activities remain unchanged during the same irradiation and incubation period. The treatment of cells with cycloheximide prevents the response triggered by UVB exposure. These findings suggest that an inducible antioxidant defence mechanism operates on photo-oxidative stress and that both superoxide dismutase and DT-diaphorase may display a concerted antioxidant role.
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PMID:Antioxidant adaptive response in human blood mononuclear cells exposed to UVB. 920 76

Human amyotrophic lateral sclerosis (ALS), a typical motor neuron disease, is characterized pathologically by selective degenerative loss of motoneurons in the CNS. We have demonstrated significant reductions of neurotransmitter-related factors, such as acetylcholine-(ACh)-synthesizing enzyme activity and glutamate and aspartate contents in the ALS, compared to the non-ALS spinal cord obtained at autopsy. We have also shown considerable reductions in activities of cytochrome-c oxidase (CO), an enzyme contributing to aerobic energy production, and transglutaminase (TG), a Ca(2+)-dependent marker enzyme for tissue degeneration, in the ALS spinal cord. We found marked increases in fragmented glial fibrillary acidic protein (GFAP), a filamentous protein specifically associated with reactive astrocytes, in the ALS spinal cord relative to non-ALS tissue. These biochemical results corresponded well to pathomor-phological neuronal degenerative loss and reactive proliferation of astroglial components in the ALS spinal cord tissue. However, these results only indicate the final pathological and biochemical outcomes of ALS, and it is difficult to follow up cause and process in the ALS spinal cord during progression of the disease. Therefore, we used an animal model closely resembling human ALS, motor neuron degeneration (Mnd) mutant mice, a subline of C57BL/6 that shows late-onset progressive degeneration of lower motor neurons with paralytic gait beginning around 6.5 mo of age, to follow the biochemical and pathological alterations during postnatal development. We detected significant decreases in CO activity during early development and in activity of superoxide dismutase (SOD), an antioxidant enzyme, in later stages in Mnd mutant spinal cord tissue. TG activity in the Mnd spinal cord showed gradual increases during early development reaching a maximum at 5 mo, and then tending to decrease thereafter. Amounts of fragmented GFAPs increased continuously during postnatal development in Mnd spinal cord. These biochemical changes were observed prior to the appearance of clinical motor dysfunctions in the Mnd mutant mice. Such biochemical analyses using appropriate animal models will be useful for inferring the origin and progression of human ALS.
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PMID:Neurochemical changes in the spinal cord in degenerative motor neuron diseases. 964 76

Our previous results indicated that 3-d-old dark-grown chilling-sensitive maize (Zea mays L.) seedlings did not survive 7 d of 4[deg]C chilling stress, but 69% of them survived similar stress when the seedlings were either preexposed to 14[deg]C for 3 d or pretreated with 0.1 mM H2O2 for 4 h at 27[deg]C (T.K. Prasad, M.D. Anderson, B.A. Martin, C.R. Stewart [1994] Plant Cell 6: 65-74) or 1 mM abscisic acid (ABA) for 24 h at 27[deg]C (M.D. Anderson, T.K. Prasad, B.A. Martin, C.R. Stewart [1994] Plant Physiol 105: 331-339). We discovered that chilling imposed oxidative stress on the seedlings. Since H2O2 accumulated during the periods of both acclimation and nonacclimation, we concluded that H2O2 had dual effects at low temperature: (a) During acclimation, its early transient accumulation signals the induction of antioxidant enzymes such as catalase 3 and peroxidase to scavenge H2O2; and (b) at 4[deg]C in nonacclimated seedlings, it accumulates to damaging levels in the tissues because of low levels of these and perhaps other antioxidant enzymes. Three-day-old seedlings pretreated with H2O2 (a mild oxidative stress) or ABA showed induced chilling tolerance. In the present study, we investigated whether mitochondria are a target for chilling-induced oxidative stress and, if so, what differences do acclimation, H2O2, or ABA make to protect mitochondria from irreversible chilling injury. The results indicated that chilling, in general, impairs respiratory activity, the cytochrome pathway of electron transport, and ATPase activity regardless of the treatment. In pretreated seedlings, the activities of catalase 3 and peroxidase in the mitochondria increased severalfold compared with control and nonacclimated seedlings. The increases in these antioxidant enzymes imply that mitochondria are under oxidative stress and such increases could initiate a protective mechanism in the mitochondria. Mitochondrial respiration is partially cyanide resistant during chilling stress and also after the 1st d of recovery. Upon further recovery over 3 d, in contrast to nonacclimated seedlings, the mitochondria of acclimation-, H2O2-, and ABA-treated seedlings showed the following recovery features. (a) The mitochondrial respiration changed from a cyanide-resistant to a cyanide-sensitive cytochrome pathway, (b) cytochrome oxidase activity recovered to control levels, (c) the ability of mitochondria to generate ATP was regained, and (d) the antioxidant enzyme activities remained at or above control levels. Based on these results, we conclude that chilling impairs mitochondrial function and that chilling-induced oxidative stress seems to be a factor, at least in part, for causing possible irreversible damage to the mitochondrial membrance components. Acclimation, H2O2, and ABA provide a protective mechanism by inducing antioxidant enzymes to protect mitochondria from irreversible oxidative damage that is absent in nonacclimated seedlings. Therefore, we conclude that the ability of the seedlings to recover from chilling injury is, at least in part, due to the ability of the mitochondria to resume normal function.
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PMID:Acclimation, Hydrogen Peroxide, and Abscisic Acid Protect Mitochondria against Irreversible Chilling Injury in Maize Seedlings. 1223 29

Moderate exercise in a treadmill (10, 15, and 20 cm/s, for 5 min each, weekly) from 28 to 78 wk of age extended male and female mice life span by 19 and 9% accompanied by 36 and 13% and 13 and 9% increased performance in behavioral assays (tightrope and T-maze tests) at 52 wk of age. Moderate exercise significantly decreased the aging-associated development of oxidative stress by preventing 1) the increase in protein carbonyls and thiobarbituric acid-reactive substances contents of submitochondrial membranes; 2) the decrease in antioxidant enzyme activities (Mn- and Cu,Zn-superoxide dismutase and catalase); and 3) the decrease in mitochondrial NADH-cytochrome-c reductase and cytochrome oxidase activities observed at 52 wk of mice age in brain, heart, liver, and kidney. These effects were no longer significant at 78 wk of age in mice. Moderate exercise, started at young age in mice, increased life span, decreased oxidative stress, and prevented the decline of cytochrome oxidase activity and behavioral performance at middle age but not at old age.
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PMID:Beneficial effects of moderate exercise on mice aging: survival, behavior, oxidative stress, and mitochondrial electron transfer. 1461 75

Several studies on mitochondrial functions following brief exposure (5-15 min) to dopamine (DA) in vitro have produced extremely variable results. In contrast, this study demonstrates that a prolonged exposure (up to 2 h) of disrupted or lysed mitochondria to DA (0.1-0.4 mM) causes a remarkable and dose-dependent inhibition of complex I and complex IV activities. The inhibition of complex I and complex IV activities is not prevented by the antioxidant enzyme catalase (0.05 mg/ml) or the metal-chelator diethylenetriaminepentaacetic acid (0.1 mM) or the hydroxyl radical scavengers like mannitol (20 mM) and dimethyl sulphoxide (20 mM) indicating the non-involvement of *OH radicals and Fenton's chemistry in this process. However, reduced glutathione (5 mM), a quinone scavenger, almost completely abolishes the DA effect on mitochondrial complex I and complex IV activities, while tyrosinase (250 units/ml) which catalyses the conversion of DA to quinone products dramatically enhances the former effect. The results suggest the predominant involvement of quinone products instead of reactive oxygen radicals in long-term DA-mediated inactivation of complex I and complex IV. This is further indicated from the fact that significant amount of quinones and quinoprotein adducts (covalent adducts of reactive quinones with protein thiols) are formed during incubation of mitochondria with DA. Monoamine oxidase A (MAO-A) inhibitor clorgyline also provides variable but significant protection against DA induced inactivation of complex I and complex IV activities, presumably again through inhibition of quinoprotein formation. Mitochondrial ability to reduce tetrazolium dye 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) in presence of a respiratory substrate like succinate (10 mM) is also reduced by nearly 85% following 2 h incubation with 0.4 mM DA. This effect of DA on mitochondrial function is also dose-dependent and presumably mediated by quinone products of DA oxidation. The mitochondrial dysfunction induced by dopamine during extended periods of incubation as reported here have important implications in the context of dopaminergic neuronal death in Parkinson's disease (PD).
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PMID:Inhibition of rat brain mitochondrial electron transport chain activity by dopamine oxidation products during extended in vitro incubation: implications for Parkinson's disease. 1592 94


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