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1.
为探讨紫外线对晶状体的损伤机制,用RT-PCR方法(reversetranscription-polymerasechainreaction,反转录聚合酶链反应),研究经紫外线照射后大鼠晶状体抗氧化相关酶,包括铜锌-超氧化物歧化酶(copper-zinc-superoxidedismutase,Cu-Zn-SOD),谷胱甘肽过氧化物酶(glu-tathioneperoxidase,GSH-Px)和过氧化氢酶(catalase,CAT)等mRNA的表达.结果显示,短时间的照射(2~5min),抗氧化相关酶的mRNA表达水平有增高表现,随后其mRNA表达水平开始下降,15min时抗氧化相关酶mRNA的表达下降更为明显,与对照组相比有非常显著性差异(P<0.001).照射后24h,抗氧化相关酶的mRNA表达有不同程度的恢复;照射后48h,其mRNA表达水平基本恢复,与对照组相比没有显著性差异.从而从基因水平上初步探讨了紫外线的氧化损伤机制  相似文献   

2.
复方抗敏灵对哮喘大鼠自由基影响的实验研究   总被引:2,自引:0,他引:2  
为了研究中药复方抗敏灵抗哮喘的作用机理,本实验测定了复方抗敏灵对哮喘大鼠红细胞中的丙二醛(MDA)、共轭双烯(CD)以及谷光甘肽过氧化物酶(GSH-Px)、过氧化氢酶(Cat)变化的影响。观察结果哮喘大鼠血中MDa、CD含量明显升高,GSH-Px、Cat活性明显降低,而中西药均能降低MDA、CD含量,提高GSH-Px和Cat活性.且中药组效果明显优于西药组。表明中药复方抗拉灵具有调解过氧化反应与抗氧化酶之间平衡的功能,对支气管哮喘起到一定的防治作用。  相似文献   

3.
Extremely low‐frequency electromagnetic fields (ELF‐EMFs) may cause negative health effects. This study aimed to investigate the direct and indirect effects of chronic exposure to extremely low‐frequency electric and magnetic fields on the prevalence of musculoskeletal disorders (MSDs). In this cross‐sectional study, 152 power plant workers were enrolled. The exposure level of employees was measured based on the IEEE Std C95.3.1 standard. Superoxide dismutase (SOD), catalase (Cat), glutathione peroxidase (GPx), total antioxidant capacity (TAC), and malondialdehyde (MDA) (independent variables) were measured in the serum of subjects. The Nordic musculoskeletal questionnaire was used to assess MSDs (dependent variable). The mean exposure of electric and magnetic fields were 4.09 V/m (standard deviation [SD] = 4.08) and 16.27 µT (SD = 22.99), respectively. Increased levels of SOD, Cat, GPx, and MDA had a direct significant relation with MSDs. In the logistic regression model, SOD (odds ratio [OR] = 0.952, P = 0.026), GPx (OR = 0.991, P = 0.048), and MDA (OR = 0.741, P = 0.021) were significant predictors of MSDs. ELF‐EMFs were not related to MSDs directly; however, increased levels of oxidative stress may cause MSDs. Bioelectromagnetics. 2019;40:354–360. © 2019 Bioelectromagnetics Society.  相似文献   

4.
It has been reported that acetyl-l-carnitine (AcCn) can reduce the degenerative processes in the central nervous system of rats, modify the fluidity of membranes and decrease the accumulation of lipofuscins in neurones. In light of these considerations we have assayed the in vitro effect of acetyl-l-carnitine on spontaneous and induced lipoperoxidation in rat skeletal muscle; in addition, the effect of AcCn on XD/XO ratio was evaluated. The presence of AcCn (10–40 mM) in incubation medium significantly reduced MDA and conjugated diene formation in rat skeletal muscle; moreover, a significant decrease in induced MDA levels was observed when microsomal preparation where incubated in the presence of 10–40 mM AcCn. Since a significant reduction of XO activity was detected in the presence of 10–80 mM AcCn, the reduced lipid peroxidation by AcCn seems to be due to an inhibition of XO activity.  相似文献   

5.
Maras Powder (MP) is a special kind of smokeless tobacco widely used in the southeast region of Turkey especially in Kahramanmaras and Gaziantep and other southeastern cities. It is obtained from a tobacco species, Nicotiana rustica L and ash of oak or grapevine wood. Tobacco may increase oxidative stress, which is related to the products of the oxygen metabolism taking place in all cells. Cellular antioxidants, e.g. catalase (CAT), superoxide dismutase (SOD) and glucose 6-phosphate dehydrogenase (G6PD) protect the cell against oxidative damage. An imbalance between the ROS and antioxidants in favour of ROS is described as oxidative stress. In this study, we aimed to investigate the effect of MP on antioxidant enzyme levels and lipid peroxidation. We measured malondialdehyde (MDA), CAT, SOD and G6PD levels in blood of 68 MP users and 30 healthy controls who did not use MP. CAT, SOD and G6PD levels were lower in MP users than in the controls. On the other hand, lipid peroxidation levels (MDA), one of the best indicators of cytological damage, was increased in MP users compared with the controls. The present study showed that MP increases oxidative stress, which may cause many systemic disorders, including arteriosclerosis.  相似文献   

6.
The objective of the study was to investigate the effect of moderate glomerular dysfunction on oxidative stress. We determined the plasma and erythrocyte malondialdehyde (MDA) levels, as a marker of lipid peroxidation, erythrocyte glutathione (GSH) levels and activities of GSH-Px, GSH Red and SOD as an antioxidant enzymes, and plasma trace element levels containing Fe, Cu and Zn in twenty proteinuric patients (6.8 +/- 5.1 g/day) with moderate glomerular function and in 20 anemic control subjects. We found that the erythrocyte and plasma MDA levels and erythrocyte GSH-Px activities were significantly higher (p < 0.001, p < 0.001, p < 0.001, respectively) and the erythrocyte GSH levels and activities of GSH-Red and SOD activities were significantly lower (p < 0.001, p < 0.001, p < 0.001, respectively) in the patients than in the anemic subjects. Plasma Fe and Zn levels were not to be found significantly different in the patients compared to the anemic subjects. But plasma Cu levels were significantly higher in the patients (p < 0.05) when compared with the levels of anemic subjects. This study was concluded that cellular antioxidant activity decreases in proteinuric patients with moderate glomerular function. This may increase lipid peroxidation reactions by causing oxidative stress in erythrocyte membranes.  相似文献   

7.
甜杨6-磷酸葡萄糖脱氢酶在抗冻性低温诱导中的作用   总被引:5,自引:0,他引:5  
对-20℃低温锻炼及脱锻炼过程中甜杨(Populus suaveolens)幼苗的G6PDH、SOD和POD活性、MDA含量和半致死温度(LT50)进行了测定和分析.结果发现,低温锻炼在一定程度上提高了幼苗6-磷酸葡萄糖脱氢酶(G6PDH)、SOD和POD活性,降低了MDA含量和幼苗半致死温度(LT50).另外,将幼苗放回常温(脱锻炼)2 d能引起幼苗的G6PDH、SOD和POD活性的显著下降,并使LT50和MDA含量的迅速回升.结果表明,低温锻炼中G6PDH活性的增加有助于SOD和POD活性的提高,进而对幼苗的LT50和MDA含量的降低有明显的促进作用,G6PDH可能参与了SOD和POD活性的调节和抗冻性的低温诱导.  相似文献   

8.
The activity of glucose-6-phosphate dehydrogenase (G6PD) was studied in five brain areas of rats aged 5 to 90 days. The areas studied were: the olfactory bulb (OB), cortex, hippocampus, striatum and septum. The G6PD activity increased more than 2-fold from 5 to 90 days in the OB, while it was almost constant in the other areas. At every stage of development, the G6PD activity was significantly higher in the OB than in the other areas. The G6PD pattern was compared with 6-phosphogluconate dehydrogenase (6PGD), glutathione reductase (GR); glutathione peroxidase (GPX), catalase (CAT) and superoxide dismutase (SOD) in order to find synergistic interactions among activities of these enzymes during development. Over the considered period, the activity of 6PGD increased significantly in the OB, while no significant difference in activity was detected in the other areas. GR increased significantly and progressively at each developmental stage in all areas. GPX showed a progressive increase in the OB, while in other areas a significant increase was detected at 90 days only. CAT and SOD showed a different and independent pattern which differred from the G6PD pattern. CAT showed the highest level of activity at 5 days then progressively decreased or was constant until 90 days; SOD had the highest value at 5 days, than it decreased at 10 days and increased from 10 to 90 days. In all areas, G6PD activity showed three electrophoretic bands, whose relative activity changed with development. At histochemical level, we found a marked G6PD activity in the periglomerular zone of the OB, which increased with age, while other areas showed a homogeneous staining. The present results demonstrate that G6PD activity increases in the OB during the developmental stages and there is a coordinated simultaneous activation of 6PGD, GPX and GR. It is likely that this enzyme induction increases the antioxidant defense of periglomerular cells that are subject to a rapid renewal and thus much more exposed to oxidant stress.  相似文献   

9.
1. Glyceraldehyde-3-phosphate dehydrogenase (G3PD) is a glycolytic enzyme that has also been implicated in a wide variety of functions within neurons. Because of the well-documented role of G3PD as an actin-binding protein, we sought evidence for a G3PD–actin complex in synaptosomes and postsynaptic densities (PSDs).2. We have shown G3PD association with 0.5-m synaptosomal particles by immunofluorescence as similarly demonstrated for actin (Toh et al., Nature 264:648–650, 1976). An immunoblot analysis also showed G3PD and actin to be enriched in synaptosomes. Further analysis of subcellular fractions from synaptosomes showed the PSD but not the synaptosomal plasma membranes to be enriched in G3PD and actin.3. Highest levels of G3PD catalytic activity were found in synaptosomes and PSDs. Although synaptosomes showed significant activity for phosphoglyceratekinase (PGK), an enzyme in sequence with G3PD for ATP production in the glycolytic pathway, no such activity was detected in the PSD fraction.4. Our studies indicate that a G3PD–actin complex may exist at the synapse. A physical association of G3PD with endogenous F-actin in synaptosomes and PSDs was demonstrated by combined phalloidin shift velocity sedimentation/immunoblot studies. By this approach, synaptosomal G3PD–actin complexes were also found to be significantly less dense than the PSD G3PD–actin complexes.5. G3PD and PGK catalytic activity in synaptosomes suggests a role in glycolysis, as well as actin binding, in the presynaptic terminals. On the other hand, the high levels of G3PD activity in PSDs but lack of PGK activity suggests that G3PD is involved in nonglycolytic functions, such as actin binding and actin filament network organization.  相似文献   

10.
Acne vulgaris is one of the common dermatological diseases and its pathogenesis is multifactorial. In this study, we aim to determine the effects of oxidative stress in acne vulgaris. Forty-three consecutive acne patients and 46 controls were enrolled. The parameters of oxidative stress such as catalase (CAT), glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase (SOD), and malondialdehyde (MDA) in the venous blood of cases were measured spectrophotometrically. The values compared with control group, the relation between the severity and distribution of acne, and the correlation of each enzyme level were researched. CAT and G6PD levels in patients were found to be statistically decreased, and SOD and MDA levels were found to be statistically increased (P < .001). However, any statistical difference and correlation could not be found between the severity and distribution of lesions and the mean levels of enzymes. In addition, we found that each enzyme is correlated with one another. Our findings show that oxidative stress exists in the acne patients. It will be useful to apply at least one antioxidant featured drug along with the combined acne treatment.  相似文献   

11.
目的 探讨半夏总生物碱(total alkaloids from Pinellia Ternate,TAPT)对帕金森病模型大鼠的防治作用及其抗氧化机制.方法 采用脑内定位注射6-羟基多巴胺(6-OHDA)建立帕金森病大鼠模型,在模型建立成功的同时给予半夏总生物碱预防性治疗.采用Morris水迷宫进行帕金森病大鼠的行为学检测,用化学比色法检测大脑皮质及血清超氧化物歧化酶(SOD)活力、丙二醛(MDA)、过氧化氢(H2O2)和还原型谷胱甘肽(GSH)的含量.结果 与正常组比较,帕金森病模型组大鼠的逃避潜伏期明显延长(P<0.01),跨越平台次数明显减少(P<0.01);经半夏总生物碱治疗组,大鼠逃避潜伏期明显缩短(P<0.05,P<0.01),跨越平台次数明显增加(P<0.01).帕金森病模型组大鼠脑皮质及血清中MDA、H2O2的含量增加,SOD活性及GSH的含量降低(P<0.01);经半夏总生物碱治疗组,脑皮质MDA、H2O2的含量显著减少(P<0.01),皮质GSH、SOD含量显著增加(P<0.01);半夏总生物碱给药组中低浓度组、中浓度组血清MDA的含量无统计学意义(P>0.05),高浓度组血清MDA含量下降(P<0.01),各治疗组中血清H2O2含量明显下降(P<0.01),血清GSH含量显著增加(P<0.01).结论 半夏总生物碱具有改善学习记忆能力,对抗大鼠神经系统的退行性变有一定的作用,可能通过改变帕金森病模型大鼠皮质部分及血清SOD、GSH的含量,而抑制了MDA和H2O2的产生.  相似文献   

12.
The activities of catalase (Cat), superoxide dismutase (SOD), glutathione peroxidase (GSHPx), glutathione transferase (GST), glucose-6-phosphate dehydrogenase (G6PD) and glyceraldehyde3-phosphate dehydrogenase (G3PD) were studied in tissue and hemolymph of susceptible (S) (EgBS(2)) and resistant (R) (EgBR(2)) Biomphalaria alexandrina snails. The results showed that CAT and GST were higher in the hemolymph of snails susceptible to Schistosoma mansoni than in that of snails resistant to infestation, while SOD and G3PD were lower in the susceptible snails. The role of these enzymes as free radical scavengers was traced 1 and 24 h after infection of the two snail lines with S. mansoni. Moreover, the activities of SOD and G3PD were also measured 2 and 4 weeks post infection. The results revealed that the overall enzymatic activities were higher in susceptible than in resistant snail tissues. After 1 h of infection, all enzymes were increased in R and S snails except GST and G6PD which decreased in S snails. After 24 h of infection, GST increased in S snails and G3PD decreased in both S and R snails while other enzymes reached normal levels.  相似文献   

13.
Comparison of oxidative stress status between subjects with or without warts is absent in the literature. In this study, we evaluated 31 consecutive patients with warts (15 female, 16 male) and 36 control cases with no evidence of disease to determine the effects of oxidative stress in patients with warts. The patients were classified according to the wart type, duration, number, and location of lesions. We measured the indicators of oxidative stress such as catalase (CAT), glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase (SOD), and malondialdehyde (MDA) in the venous blood by spectrophotometry. There was a statistically significant increase in levels of CAT, G6PD, SOD activities and MDA in the patients with warts compared to the control group (P< .05). However, we could not define a statistically significant correlation between these increased enzyme activities and MDA levels and the type, the duration, the number, and the location of lesions. We determined possible suppression of T cells during oxidative stress that might have a negative effect on the prognosis of the disease. Therefore, we propose an argument for the appropriateness to give priority to immunomodulatory treatment alternatives instead of destructive methods in patients with demonstrated oxidative stress.  相似文献   

14.
There are numerous reports on the effects of electromagnetic radiation (EMR) in various cellular systems. Melatonin and caffeic acid phenethyl ester (CAPE), a component of honeybee propolis, were recently found to be potent free radical scavengers and antioxidants. Mechanisms of adverse effects of EMR indicate that reactive oxygen species may play a role in the biological effects of this radiation. The present study was carried out to compare the efficacy of the protective effects of melatonin and CAPE against retinal oxidative stress due to long-term exposure to 900 MHz EMR emitting mobile phones. Melatonin and CAPE were administered daily for 60 days to the rats prior to their EMR exposure during our study. Nitric oxide (NO, an oxidant product) levels and malondialdehyde (MDA, an index of lipid peroxidation), were used as markers of retinal oxidative stress in rats following to use of EMR. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in retinal tissue. Retinal levels of NO and MDA increased in EMR exposed rats while both melatonin and CAPE caused a significant reduction in the levels of NO and MDA. Likewise, retinal SOD, GSH-Px and CAT activities decreased in EMR exposed animals while melatonin and CAPE caused a significant increase in the activities of these antioxidant enzymes. Treatment of EMR exposed rats with melatonin or CAPE increased the activities of SOD, GSH-Px and CAT to higher levels than those of control rats. In conclusion, melatonin and CAPE reduce retinal oxidative stress after long-term exposure to 900 MHz emitting mobile phone. Nevertheless, there was no statistically significant difference between the efficacies of these two antioxidants against to EMR induced oxidative stress in rat retina. The difference was in only GSH-Px activity in rat retina. Melatonin stimulated the retinal GSH-Px activity more efficiently than CAPE did.  相似文献   

15.
A newborn rat model of retinopathy of prematurity was used to test the hypothesis that a lack of superoxide dismutase contributes to the retinal vaso-attenuation seen during exposure of the animals to hyperoxic conditions. To determine the endogenous superoxide dismutase activity of the retina under hyperoxic conditions, litters of albino rats were placed in either constant 80% ambient oxygen (constant hyperoxia), or placed in 21% oxygen (room air) immediately after birth. Every other day, for 14 days, several rat pups were sacrificed and their retinas removed for the determination of total superoxide dismutase (SOD) activity and manganese-associated SOD activity. An attempt was made to increase retinal SOD activity by intraperitoneal administration of exogenous SOD encapsulated in polyethylene glycol-modified liposomes. Additional litters were exposed to the same oxygen treatments and supplemented twice daily with either liposome-encapsulated superoxide dismutase in saline or liposomes containing saline without SOD. Animals were sacrificed at various time points for the determination of total superoxide dismutase activity and computer-assisted analysis of vessel density and avascular area. Animals raised in an atmosphere of constant 80% oxygen had significantly reduced levels of retinal superoxide dismutase activity through 6 days of life when compared to their room air-raised littermates. At 6 days of age, daily supplementation with liposome-encapsulated SOD had significantly increased retinal superoxide dismutase activity and reduced oxygen-induced vaso-attenuation as evidenced by increased vessel density and decreased avascular area, when compared to littermates exposed to constant hyperoxia that received control liposomes. Superoxide dismutase had no adverse effects on any of the animals regardless of treatment. Tracing experiments demonstrated that liposomes entered the retina and were found in cells morphologically resembling mi-croglia. Delivery of SOD to the retina via long-circulating liposomes proved beneficial, suggesting that restoration and/or supplementation of endogenous antioxidants in oxygen-damaged retinal tissue is a potentially valuable therapeutic strategy.  相似文献   

16.
黄芩黄酮对硒性白内障晶状体抗氧化酶表达的影响   总被引:9,自引:0,他引:9  
为探讨黄芩黄酮防治白内障的作用机理 ,采用半定量RT PCR方法比较正常组、白内障组和中药防治组大鼠晶状体中GSH Px、GR和Cu ZnSOD的mRNA水平 .白内障组GSH Px、GR和Cu ZnSOD的mRNA水平在 15d龄时显著高于正常 ,然后下降 ;在 2 7d和 31d龄 ,GR和Cu ZnSOD的mRNA水平下降至与正常无显著差异 ,GSH PxmRNA水平仍略高于正常 .中药防治组晶状体中 ,3种抗氧化酶的mRNA水平在各实验取样点无明显变化 ;其中 ,GR和Cu ZnSOD的mRNA水平一直与正常无显著差异 ,GSH PxmRNA水平略高于正常 .黄芩黄酮可能通过有效清除亚硒酸钠间接产生的活性氧来防止白内障的发生 ,并使亚硒酸钠对晶状体抗氧化酶表达的影响得以消除  相似文献   

17.
Guo L  Zhang Z  Green K  Stanton RC 《Biochemistry》2002,41(50):14726-14733
In rat pancreatic islets and insulin-producing cell lines, IL-1beta induces expression of inducible nitric oxide synthase and NO production leading to impairment of glucose-stimulated insulin release and decreased cell survival. NADPH is an obligatory cosubstrate for iNOS synthesis of NO. We hypothesized that IL-1beta stimulates an increase in activity of NADPH-producing enzyme(s) prior to NO production and that this increase is necessary for NO production. Using rat insulin-secreting RINm5F cells, we found that (1) IL-1beta caused a biphasic change in the NADPH level (increased by 6 h and decreased after prolonged incubation in the presence of 2 ng/mL IL-1beta); (2) IL-1beta stimulated increased activity of glucose-6-phosphate dehydrogenase (G6PD) in a time- and dose-dependent manner, and G6PD expression was increased by about 80% after exposure to 2 ng/mL IL-1beta for 18 h: (3) IL-1beta-stimulated NO production was positively correlated with increased G6PD activity; (4) IL-1beta did not cause any significant change in enzyme activity of another NADPH-producing enzyme, malic enzyme; (5) IL-1beta-induced NO production was significantly reduced either by inhibiting G6PD activity using an inhibitor of G6PD (dehydroepiandrosterone) or by inhibiting G6PD expression using an antisense oligonucleotide to G6PD mRNA; and (6) IL-1beta stimulated a decrease in the cAMP level. 8-Bromo-cAMP caused decreased G6PD activity, and the protein kinase A inhibitor H89 led to a increase in G6PD activity in RINm5F cells. In conclusion, our data show that IL-1beta stimulated G6PD activity and expression level, providing NADPH that is required by iNOS for NO production in RINm5F cells. Also, inhibition of the cAMP-dependent PKA signal pathway is involved in an IL-1beta-stimulated increase in G6PD activity.  相似文献   

18.
We examined oxidative stress markers of 31 patients suffering from ALS, 24 patients suffering from PD and 30 healthy subjects were included. We determined the plasma levels of lipid peroxidation (malondialdehyde, MDA), of protein oxidative lesions (plasma glutathione, carbonyls and thiols) and the activity of antioxidant enzymes i.e. erythrocyte Cu,Zn-Superoxide dismutase (SOD), Glutathione peroxidase (GSH-Px) and catalase. MDA and thiols were significantly different in both neurodegenerative diseases versus control population. A trend for an enhancement of oxidized glutathione was noted in ALS patients. Univariate analysis showed that SOD activity was significantly decreased in ALS and GSH-Px activity was decreased in PD. After adjusting for demographic parameters and enzyme cofactors, we could emphasize a compensatory increase of SOD activity in PD. Different antioxidant systems were not involved in the same way in ALS and PD, suggesting that oxidative stress may be a cause rather than a consequence of the neuronal death.  相似文献   

19.
Two X-linked mutations that give rise to overproduction of glucose-6-phosphate dehydrogenase (G6PD) were found among the progenies of isogenic strains which had been subjected to selection for high G6PD activity. Mapping of the high-activity factor in these mutants was carried out using car Zw B sw males of low G6PD activity. As a result, the factor mapped 0.02–0.04 unit to the left of the Zw locus. The amount of the G6PD gene was also quantitated utilizing a cloned G6PD gene as a probe, but no significant difference was found between the mutants and low-G6PD activity flies which shared the same X, second, and third chromosomes with the mutants. These findings are consistent with our notion that the mutations might be regulatory mutations, possibly resulting from the insertion of a novel class of transposable genetic elements.This research was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture, Japan.  相似文献   

20.
G6PD from erythrocytes and leukocytes had similar electrophoretic mobility, G6P K m value, 2dG6P utilization rate, and thermostability. This was found in normal subjects and in the deficient variants Canton, B(–)Chinese, and Hong Kong, indicating that the genetic locus for the control of G6PD in both cells is the same. G6PD B(–)Chinese is reported for the first time.  相似文献   

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