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71.
大豆黄酮抗热应激作用   总被引:1,自引:0,他引:1  
江芸  高峰 《中国公共卫生》2006,22(2):169-170
目的研究大豆黄酮对热应激小鼠谷胱甘肽过氧化物酶(GSH-Px)活力及丙二醛(MDA)含量的影响。方法将30只小鼠随机分为正常对照组、热应激组和大豆黄酮热应激组,以(45±1)℃持续20 min的热应激模式,观察热应激后小鼠肝、脾、肾及血清中GSH-Px活力及MDA含量变化。结果与正常对照组相比,热应激后小鼠肝脏、脾脏及肾脏GSH-Px活力升高,其中肝脏酶活力显著升高(P<0.05);大豆黄酮热应激组酶活力显著高于正常对照组(P<0.05或P<0.01),肝脏、脾脏酶活力显著高于应激组(P<0.05)。热应激后2组MDA含量均比正常对照组升高,其中肝脏和血清上升显著(P<0.05);大豆黄酮热应激组比应激组有所下降,但差异无统计学意义(P>0.05)。结论大豆黄酮可增强应激机体的抗氧化能力。  相似文献   
72.
三种饮用水对小鼠抗过氧化酶影响比较   总被引:1,自引:0,他引:1  
目的比较不同饮用水对小鼠的抗过氧化酶的影响。方法ICR小鼠随机分为三组,每组雌雄各半,分别用矿泉水、自来水和纯净水喂养。经过一年时间喂养后,取其肺、肝、脑、心制成匀浆测定谷胱甘肽过氧化物酶(GSH-Px)、总超氧化物歧化酶(SOD)活力。结果矿泉水组小鼠的心匀浆GSH-Px活力较纯净水组高,有显著差异(P<0.05);而SOD活力矿泉水组除在肺匀浆中明显高于其他两组(P<0.05),肝中SOD纯净水组高于矿泉水组。结论不同饮用水对小鼠组织器官的抗氧化酶影响不同,表现出不同的抗氧化/致氧化效应。  相似文献   
73.
The potential health benefits of tea have long been studied. This study examined the role of powdered sea buckthorn leaf tea (SLT) in high-fat diet-induced obese mice. The mice were fed two different doses of SLT (1% and 5%, wt/wt) for six weeks. SLT suppressed body weight gain in a dose-dependent manner and significantly reduced visceral fat, plasma levels of leptin, triglyceride and total cholesterol and ALT activity compared with the high-fat-fed control mice. SLT also decreased hepatic triglyceride and cholesterol concentrations and lipid accumulation, whereas elevated fecal lipid excretion. High-fat feeding resulted in simultaneously decreasing hepatic FAS and G6PD activities and increasing PAP, β-oxidation and CPT activities. However, SLT supplementation during high-fat feeding led to a significant decrease in PAP, β-oxidation and CPT activities with a simultaneous increase in G6PD activity. The hepatic CYP2E1 activity and hepatic and erythrocyte lipid peroxides were significantly lowered with SLT supplements. Hepatic and erythrocyte SOD and CAT activities were also increased with SLT supplements in a dose-dependent manner, whereas GSH-Px activity was increased in erythrocytes only. These results indicate that SLT has potential anti-visceral obesity and antioxidant effects mediated by the regulation of lipid and antioxidant metabolism in high-fat diet-induced obese mice.  相似文献   
74.
The present study aims to investigate whether Lycium barbarum polysaccharides (LBP) could protect against acute doxorubicin (DOX)-induced cardiotoxicity. Rats received daily treatment of either distilled water (4 ml/kg) or LBP (200 mg/kg) for 10 days and then followed by an intravenous injection at day 7 of either saline (10 ml/kg) or DOX (10 mg/kg). DOX induced significantly myocardial damage in rats, which were characterized as conduction abnormalities, decreased heart-to-body weight ratio, increased serum CK, and myofibrillar disarrangement. DOX treatment also increased MDA and decreased SOD and GSH-Px activity in cardiac tissues. Pretreatment with LBP significantly reduced DOX-induced oxidative injury in cardiac tissue, suggesting by the fact that LBP significantly attenuated DOX-induced cardiac myofibrillar disarrangement and LBP was effective in decreasing the levels of serum CK and thus improving conduction abnormalities caused by DOX. LBP treatment significantly increased SOD and GSH-Px activity and decreased the MDA level of heart tissues damaged by DOX exposure in rats. Furthermore, the cytotoxic study showed that LBP protect against cytotoxicity of DOX in cardiac myoblasts H9c2 but dose not attenuate the anti-tumor activity of DOX. In summary, our evidence indicates that LBP elicited a typical protective effect on DOX-induced acute cardiotoxicity via suppressing oxidative stress.  相似文献   
75.
背景与目的:探讨不同浓度的葡萄籽提取物(GSE)对老龄大鼠抗氧化的作用.材料与方法:取wistar大鼠40只,设葡萄籽提取物0.1、0.5、2.5 g/kg 3个剂量组和1个溶剂对照组,每组10只,灌胃给予受试物,每天1次,连续60 d.于第61 d股静脉取血并杀鼠取肝脏制备肝匀浆,分别测定血清过氧化脂质(MDA)和谷胱甘肽氧化酶(GSH-Px)、肝组织超氧化歧化酶(SOD).结果:3个剂量组SOD活性与溶剂对照组比较差异均无统计学意义(P>0.05).仅2.5 g/kg剂量组所测的MDA含量和GSH-Px与溶剂对照组比较差异均有统计学意义(P<0.01).结论:葡萄籽提取物有降低雌性老年大鼠(鼠龄15个月)血清中MDA含量、升高血清中GSH-Px活性的作用,提示其具有一定的抗氧化作用.  相似文献   
76.
中药白芍水煎剂给予老龄小鼠灌胃(10g/kg),每日一次,连用4周。采用邻苯三酚自氧化法、DTNB和TBA比色法测定红细胞超氧化物歧化酶(SOD)活性,全血谷胱甘肽过氧化物酶(GSH-Px)活力和红细胞中及血浆中MDA含量。结果表明,白芍水煎剂能显著增强老龄小鼠红细胞SOD活性、全血GSH-Px的活力,而且可显著降低红细胞和血浆中MDA含量,故具有延缓衰老作用。  相似文献   
77.
Aluminium is present in many manufactured foods and medicines and is also added to drinking water during purification purposes. Therefore, the present experiment was undertaken to determine the effectiveness of propolis in alleviating the toxicity of aluminium chloride (AlCl3) on biochemical parameters, antioxidant enzymes and lipid peroxidation of male Wistar Albino rats. Animals were assigned to 1 of 4 groups: control; 34 mg AlCl3/kg bw; 50 mg propolis/kg bw; AlCl3 (34 mg/kg bw) plus propolis (50 mg/kg bw), respectively. Rats were orally administered their respective doses daily for 70 days. The levels of thiobarbituric acid reactive substances (TBARS) was increased, and the activities of glutathione S-transferase, superoxide dismutase, catalase and glutathione peroxidase were decreased in liver, kidney and brain of rats treated with AlCl3. While, TBARS was decreased and the antioxidant enzymes were increased in rats treated with propolis alone. Plasma transaminases, lactate dehydrogenase, glucose, urea, creatinine, bilirubin, total lipid, cholesterol, triglyceride and LDL-c were increased, while total protein, albumin and high HDL-c were decreased due to AlCl3 administration. The presence of propolis with AlCl3 alleviated its toxic effects in rats treated with AlCl3. It can be concluded that propolis has beneficial influences and could be able to antagonize AlCl3 toxicity.  相似文献   
78.
The constitutive and inducible expression of aryl hydrocarbon receptor (AhR) and of the AhR-regulated genes coding for CYP1A1, CYP1A2, CYP1B1, CYP2S1, and Nrf2 was investigated by real-time or traditional PCR in cerebral areas (cortex, cerebellum, midbrain, and hippocampus), blood–brain interfaces (meninges and brain microvessels) and liver obtained from control pigs and from pigs treated with β-naphthoflavone (βNF), a potent AhR agonist. The enzymatic activities of ethoxyresorufin-O-deethylase (EROD), and methoxyresorufin-O-deethylase (MEROD), marker for CYP1A1 and CYP1A2, the GST and various antioxidant enzymes (catalase, superoxide dismutase, GSSG-reductase, and GSH-peroxidase) were also determined in the same CNS regions. The AhR, CYP1A1, CYP1A2, CYP1B1, Nrf2 mRNAs were detected, although at different extent, in all the CNS regions, while CYP2S1 mRNA was detected only in midbrain. In the blood–brain interfaces, the constitutive basal expression of AhR and CYP1A1 was comparable to the hepatic one and even higher for CYP1B1 and Nrf2. The treatment with βNF determined the induction of CYP1A1 and 1B1 (but not of AhR, CYP1A2, and Nrf2) mRNA levels in various CNS areas; notably, CYP1A1 mRNA was increased to about 300-fold in the microvessels. The analysis of enzymatic activities revealed that EROD, but not MEROD, was induced in microsomes but not in mitochondria of all the CNS areas. However, the mitochondrial EROD activities were comparable (in midbrain, meninges) or higher (in cortex, cerebellum, hippocampus) than the microsomal ones, suggesting an important metabolic function of CYP1A1 in this subcellular localization. The activities of GST and antioxidant enzymes were detected in all CNS tissues, with levels lower than the hepatic ones, but found quite evenly distributed and marginally affected by βNF treatment. The high expression of metabolic enzymes found in blood–brain interfaces could represent a very important defence toward toxins of CNS.  相似文献   
79.
作者测定了矽尘作业者和对照组血超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)的活性变化,结果是矽尘作业者和健康对照组SOD、GSH-Px的活性分别为2.396±0.413(×10~3u/gHb)、35.06±6.94(μmol GSH被氧化量/min·gHb)和2.098±0.591(×10~3u/gHb)、27.41±9.20(μmol GSH被氧化量/min·gHb),前者均显著高于后者,同时SOD、GSH-Px活性高尘龄组也显著高于低尘龄组,揭示长期接触矽尘机体内的脂质过氧化和抗过氧化活性均处于亢奋状态。抗脂质过氧化活性的增强,可能是机体的一种防御性机制,是矽尘作业者机体对二氧化硅细胞毒性作用的不同阶段的反应。  相似文献   
80.
李艳红  刘坚  江波  张涛 《营养学报》2008,30(2):161-164
目的研究不同剂量鹰嘴豆蛋白酶解物(CPH)对D-半乳糖致衰小鼠血清、心脏和肝脏抗氧化能力的影响。方法D-半乳糖连续颈部注射制作亚急性衰老的小鼠模型,采用生物化学方法检测各组小鼠血清、心脏和肝组织匀浆中超氧化物岐化酶(SOD)、谷胱苷肽过氧化物酶(GSH-Px)的活力及丙二醛(MDA)的含量。结果D-半乳糖致衰小鼠SOD活力、GSH-Px活力均明显下降,MDA含量明显上升,与正常小鼠比较差异显著;不同剂量的鹰嘴豆蛋白酶解物灌胃给药后均能提高小鼠血清、肝脏和心脏组织中的SOD和GSH-Px,同是降低血清、心脏和肝脏组织中MDA浓度;其效果与VE效果相当。结论鹰嘴豆蛋白酶解物能显著提高亚急性衰老小鼠的抗氧化能力,尤以高剂量组效果最好,具有一定延缓衰老的作用。  相似文献   
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