Changes in Superoxide Dismutase Activity in Liver and Lung of Old Rats

Superoxide dismutase activity was measured in liver and lung from 3 and 24 month-old rats. Both total SOD and Mn-SOD activity decreased significantly in the liver of old rats. Recent results from our laboratory have indicated that during aging, the activity of Cu/Zn-SOD decreases in rat liver and that there is an accumulation of altered protein. It was also shown that the old Cu/Zn-SOD had one histidine fewer than the young one. In the present study, the immunoprecipitation experiments showed that the amount of immunoprecipitable Mn-SOD from liver of old rats was greater than from young ones, but when amino acid residues were measured in purified young and old Mn-SOD from liver, no change was observed. In lung, no significant age-related differences in total SOD, Cu/Zn-SOD and Mn-SOD activity were found, nor was there accumulation of altered protein during aging.     

Vulnerability of the mid aged rat myocardium to the age-induced oxidative stress: Influence of exercise training on antioxidant defense system

This study investigated the onset of age-related changes in the myocardial antioxidant defense system (ADS) and the vulnerability of the myocardium to oxidative stress following exercise training. Few studies have investigated the influence of the most prevalent life-prolonging strategy physical exercise, on the age-dependent alterations in the myocardial antioxidant enzyme system of female rats at mid age and to determine whether exercise-induced ADS could attenuate lipid peroxidation. Two age groups young (3 months old) and mid age (12 months old) Wistar strain female albino rats were given chronic exercise training for a period of 12 weeks. We found a striking decrease (p < 0.01) in the activity levels of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) in the myocardium of mid aged rats when compared to young rats by 36, 50 and 29%, respectively, suggesting the onset of age-dependent decrease in the myocardial ADS. A similar age-related decrease (p < 0.01) was observed in the reduced glutathione (GSH) content (36%). Despite the reduction in ADS, lipid peroxidation (LPO) (20%) was also decreased. In contrast, exercise training significantly elevated (p < 0.01) these antioxidant enzyme activities and the content of GSH. The increase in SOD and CAT activities were more pronounced in the mid aged rats when compared to younger rats, but increased the level of lipid peroxidation to higher levels in the mid-age group following the training regimen. The findings of the present study suggest that, although the activity levels of the myocardial antioxidant enzymes were elevated with the 12 weeks of exercise training, the changes were not sufficient enough in attenuating oxidative stress in the myocardium of female rats during this short period of exercise training.     

超氧化物歧化酶(SOD)研究进展

环境胁迫使植物细胞中积累大量的活性氧,从而导致蛋白质、膜脂、DNA及其它细胞组分的严重损伤。植物体内有效清除活性氧的酶类包括超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、过氧化氢酶(CAT)等,其中研究最深入的是SOD。利用基因工程策略增加这些物质在植物体内的含量,从而获得抗逆转基因植株。     

Isolation and genetic analysis of a mutation that suppresses the auxotrophies of superoxide dismutase-deficient Escherichia coli K12

Summary The most striking phenotype associated with superoxide dismutase (SOD) deficiency in Escherichia coli is the inability to grow in aerobic minimal medium, which is due to the sensitivity of several amino acid biosynthetic pathways to superoxide. We have isolated two classes of pseudorevertants that grow on minimal medium at modest rates. Of these, the class that exhibited the faster growth carries mutations at a single locus, denoted ssa, which was mapped to 4 min on the E. coli chromosome. This class constituted the majority of the spontaneous pseudorevertants that were selected by the transfer of independent SOD-deficient cultures in minimal medium from anaerobic to aerobic growth conditions. Pseudoreversion at ssa suppressed requirements for a variety of unrelated amino acid supplements. Further, the SOD-deficient strains were unable to assimilate diaminopimelic acid from the growth medium, whereas the ssa pseudorevertants did so. The viability of these pseudorevertants indicates that superoxide-sensitive biosynthetic enzymes do retain some function in SOD-deficient cells during aerobic growth.     

Chronic fenfluramine treatment of rats with different ages: Effects on brain oxidative stress-related parameters

Fenfluramine is an anorectic drug widely used for the regulation of food intake that presents some adverse effects at the central and peripheral levels. d-Fenfluramine, an isomer of dl-fenfluramine, is postulated to be more effective and to induce less side effects than the racemic compound. These drugs act preferentially on the serotonergic system. Some authors have suggested that fenfluramine causes a degeneration of serotonergic neurons. Alterations of the serotonergic system are also observed during the aging process, and in this case, a relationship with reactive oxygen species has been already established. In view of these data, the present study was conducted to investigate the relationship between fenfluramine and brain antioxidant defense system in mature and aged animals. Rats aged 4 and 17 months were chronically treated with dl-fenfluramine, d-fenfluramine, or saline. Brain activity of superoxide dismutase and glutathione peroxidase was significantly affected by aging. Catalase activity was altered by the treatment. Total glutathione content and chemiluminescence in the brains were also altered by aging. Glutathione levels were altered as a function of the interaction between age and treatment. These findings suggest that treatment with d- or dl-fenfluramine results in alteration of the antioxidant system that could be exacerbated when associated with the aging process. © 1997 John Wiley & Sons, Inc.     

Alterations in Antioxidant Enzymes During Aging in Humans

The oxidative stress theory of aging offers the best mechanistic elucidation of the aging phenomenon and other age-related diseases. The susceptibility of an individual depends on the antioxidant status of the body. In humans, the antioxidant system includes a number of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), nonenzymatic antioxidants such as glutathione (GSH), protein –SH, ascorbic acid, and uric acid, and dietary antioxidants. Antioxidant enzymes form the first line of defense against reactive oxygen species. In an earlier report, we showed that the plasma antioxidant potential in humans decreases as a function of age and that there are compensatory mechanisms operating in the body which are induced to maintain the antioxidant capacity during aging. In the present study, we report the relationship between human aging and antioxidant enzymes SOD and CAT; we also correlate the activity of these enzymes with the antioxidant capacity of the plasma. Our results show a significantly higher plasma SOD and CAT activity in older individuals than in younger individuals. The induction in activity of SOD and CAT during human aging may be a compensatory response of the individual to an increased oxidative stress.     

Age-related increases in superoxide dismutase activity and thiobarbituric acid-reactive substances: Effect of bio-catalyzer in aged rat brain

This study describes, using electron spin resonance spectrometry/spin trapping technique, the increase superoxide dismutase (SOD) activity in the mitochondrial and cytosolic fraction of the cortex, midbrain, pons-medulla oblongata and cerebellum, and in thiobarbituric acid-reactive substances (TBARS) in the cortex, cerebellum and hippocampus of the aged rats. The results show that corresponding to the increased life span and improved physical conditions observed after peroral long-term treatment with Bio-catalyzer, a commercial natural fermented health food supplement marketed in Japan and in the Philippines and earlier reported to be a hydroxyl radical scavenger with weaker scavenging activity on superoxide radical (O ₂ ^– ), SOD which is involved in the metabolic degradation of O ₂ ^– was further increased, whereas TBARS decreased. These findings suggest that the increased SOD activity in the brain as a defense mechanism against age-related accumulation of reactive oxygen species, in particular superoxide radicals, was enhanced with Biocatalyzer treatment while age-related peroxidation of neuronal membrane, as measured by TBARS, was decreased.     

Deterioration of ischemia/reperfusion-induced acute renal failure in SOD1-deficient mice

Reactive oxygen species (ROS) are likely candidates for involvement in ischemia/reperfusion-induced acute renal failure (ARF). In this study, the issue of whether superoxide dismutase (SOD1)-deficiency exacerbates the ischemia/reperfusion-induced ARF was examined. At two weeks after a right nephrectomy of mice, the left renal vessels were clipped to induce renal ischemia and were then released after 45 min. The severe renal damage observed at one day was partially recovered at seven days after the induction of ischemia. SOD1^- / -  mice suffer from severe ARF compared with SOD1^+/ -  and SOD1^+/+ mice. The damage was more evident in aged animals (24-28 week old) than younger ones (10-12 week old). The expression of major antioxidative and redox enzymes, except for CuZnSOD, were substantially unchanged. Thus, the increased ARF in SOD1^- / -  mice appears to be mainly attributable to a deficiency in CuZnSOD. These data support the view that ROS are exacerbating factors in ischemia/reperfusion-induced ARF.     

Deterioration of ischemia/reperfusion-induced acute renal failure in SOD1-deficient mice

Reactive oxygen species (ROS) are likely candidates for involvement in ischemia/reperfusion-induced acute renal failure (ARF). In this study, the issue of whether superoxide dismutase (SOD1)-deficiency exacerbates the ischemia/reperfusion-induced ARF was examined. At two weeks after a right nephrectomy of mice, the left renal vessels were clipped to induce renal ischemia and were then released after 45 min. The severe renal damage observed at one day was partially recovered at seven days after the induction of ischemia. SOD1^{? / ?} mice suffer from severe ARF compared with SOD1^{+/ ?} and SOD1^+/+ mice. The damage was more evident in aged animals (24–28 week old) than younger ones (10–12 week old). The expression of major antioxidative and redox enzymes, except for CuZnSOD, were substantially unchanged. Thus, the increased ARF in SOD1^{? / ?} mice appears to be mainly attributable to a deficiency in CuZnSOD. These data support the view that ROS are exacerbating factors in ischemia/reperfusion-induced ARF.     

动物抗氧化系统中主要抗氧化酶基因的研究进展

抗氧化系统是机体清除体内多余的活性氧、保护自身免受氧化损伤的重要体系,其中超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶等起主要作用。本文将对动物抗氧化系统中,超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶基因的种类、分布、结构及表达进行综述。     

Effects of a carotene-deficient diet on measures of oxidative susceptibility and superoxide dismutase activity in adult women

The effect of consuming a low carotene diet (≈60 μg carotene/day) on oxidative susceptibility and superoxide dismutase (SOD) activity in women living in a metabolic research unit was evaluated. The diet had sufficient vitamins A, E, and C. The women ate the diet supplemented with 1500 μg/day β-carotene for 4 days (baseline), then the unsupplemented diet for 68 days (depletion), followed by the diet supplemented with > 15,000 μg/day carotene for 28 days (repletion). Production of hexanal, pentanal, and pentane by copper-oxidased plasma low density lipoproteins from carotene-depleted women was greater than their production of these compounds when repleted with carotene. Erythrocyte SOD activity was depressed in carotene-depleted women; it recovered with repletion. Thiobarbituric acid reactive substances in plasma of carotene-depleted women were elevated and diminished with repletion. Dietary carotene seems to be needed, not only as a precursor of vitamin A, but also to inhibit oxidative damage and decrease oxidation susceptibility.     

木脂素类化合物的SOD活性研究

超氧化物歧化酶,是生物体内对超氧阴离子自由基(O_2~-)的最有效的清除剂,但由于SOD分子量大,体内代谢速度快,作为外源性药物有其不足之处。从中草药中寻找具SOD活性的有效成分,更好发掘天然药物的研究。从地血香分离出四种联苯环烯木脂素类化合物,进行了SOD活性研究。实验证明四种化合物的SOD活性不同,分别测定了它们对O_2~-的清除率和抑制率。     

Discovery of superoxide reductase: an historical perspective

For more than 30 years, the only enzymatic system known to catalyze the elimination of superoxide was superoxide dismutase, SOD. SOD has been found in almost all organisms living in the presence of oxygen, including some anaerobic bacteria, supporting the notion that superoxide is a key and general component of oxidative stress. Recently, a new concept in the field of the mechanisms of cellular defense against superoxide has emerged. It was discovered that elimination of superoxide in some anaerobic and microaerophilic bacteria could occur by reduction, a reaction catalyzed by a small metalloenzyme thus named superoxide reductase, SOR. Having played a major role in this discovery, we describe here how the concept of superoxide reduction emerged and how it was experimentally substantiated independently in our laboratory.Abbreviations Dfx desulfoferrodoxin - SOD superoxide dismutase - SOR superoxide reductase