柠檬酸对小鼠睾丸组织抗氧化酶活性的影响

为研究柠檬酸对小鼠睾丸组织抗氧化酶活性的影响,将40只健康昆明系小鼠随机分为对照组(生理盐水)、柠檬酸低(180mg/kg)、中(270mg/kg)、高(360mg/kg)剂量组,各组小鼠每周腹腔注射相应剂量试剂0.2mL,连续注射3周,第3次注射后的第7天时颈椎脱臼处死小鼠,取其睾丸组织制作匀浆液检测过氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、乳酸脱氢酶(LDH)、总一氧化氮合酶(T-NOS)活性及丙二醛(MDA)含量。结果表明,与对照组相比,中、高柠檬酸剂量组小鼠睾丸组织SOD活性显著降低(P<0.05);柠檬酸处理组GSH-Px活性、MDA含量均显著下降(P<0.05);随着柠檬酸剂量的增加,LDH、NOS活性分别呈下降、上升趋势。此结果提示,一定剂量的柠檬酸可以降低小鼠睾丸组织SOD、GSH-Px活性,但可能通过NO途径减少睾丸细胞膜脂质过氧化,提高细胞膜的稳定性。     

柔嫩艾美耳球虫感染雏鸡LPO含量和抗自由基酶活性的动力学

通过测定柔嫩艾美耳球虫 (Eimeria tenella)感染鸡的盲肠、肝脏、脾脏和法氏囊组织中脂质过氧化物 (L PO)含量和超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GXH- Px)及过氧化氢酶 (CAT)活性 ,研究雏鸡感染球虫后机体内自由基生成和抗自由基反应。结果表明 ,雏鸡感染 E.tenella后 ,盲肠、肝脏和脾脏组织中的 L PO含量在感染后显著 (P<0 .0 5 )或极显著 (P<0 .0 1)升高 ,T- SOD、Mn- SOD、Cu、Zn- SOD、GSH- Px和 CAT活性水平不同程度下降。试验结果说明在 E.tenella感染后 ,鸡体内的氧自由基生成反应加剧 ,氧自由基参与了球虫的致病过程。     

天然芸苔素内酯缓解胺苯磺隆对后茬水稻药害的作用机理初探

通过测定天然芸苔素内酯对水稻幼苗谷胱甘肽(GSH)含量、谷胱甘肽-S-转移酶(GST)活性以及在离体和活体条件下对水稻幼苗乙酰乳酸合成酶(ALS)活力的影响,研究天然芸苔素内酯减轻胺苯磺隆对水稻药害的作用机理。结果表明,其作用机理与水稻幼苗GSH含量、GST活性变化没有太大相关性,可能与其能间接激活水稻幼苗ALS活力有较大相关。     

重组GSTA3蛋白对福美双诱导的肉鸡TD中抗凋亡基因BAG-3表达的影响

【目的】肉鸡胫骨软骨发育不良(TD)是肉鸡常见的一种骨骼性疾病,研究重组GSTA3蛋白对福美双诱导的TD肉鸡软骨细胞中抗凋亡基因BAG-3表达的影响,为治疗TD提供新的思路和方法。【方法】将120羽1周龄肉雏鸡随机分为6组(编号为A、B、C、D、E、F组)。A、B、C组为基础日粮对照组,D、E、F组为添加福美双日粮诱导TD组。试验饲喂福美双2 d诱发TD,在添加福美双第1、3、5、7天,腿部肌肉注射重组鸡GSTA3蛋白和磷酸盐缓冲液,A组与D组注射(100μg·kg-1)磷酸盐缓冲液;B组与E组注射低剂量(100μg·kg-1)GSTA3;C组与F组注射高剂量(200μg·kg-1)GSTA3。试验历时23 d。添加福美双后1、2、4、6、10和15 d采集胫骨生长板。通过Real-time qPCR检测BAG-3基因的mRNA水平,利用免疫组化来检测BAG-3蛋白表达水平。【结果】Real-time qPCR结果显示,TD损伤修复期内,相比较于基础日粮对照组,福美双对照组肉鸡胫骨生长板中BAG-3mRNA的表达水平基本都显著上调(P<0.05);相比较于福美双对照组,E和F组在...     

日本看麦娘对精噁唑禾草灵和甲基二磺隆的抗性机制

为明确抗性日本看麦娘种群对精噁唑禾草灵和甲基二磺隆的抗性机制,研究了乙酰辅酶A羧化酶(acetyl-CoA carboxylase,ACCase)和乙酰乳酸合成酶(acetolactate synthase,ALS)基因在抗性和敏感日本看麦娘种群内的差异,以及谷胱甘肽-S-转移酶(glutathione S-transferases,GSTs)的活性差异,同时测定了抗性种群AFT对不同的ACCase和ALS抑制剂类除草剂的交互抗性。结果显示:与敏感种群AH-7相比,抗性种群AFT的ACCase基因CT区的2027位氨基酸和ALS基因的574位氨基酸发生突变;AFT种群的GSTs活性经过精噁唑禾草灵和甲基二磺隆处理后明显增强,且显著强于敏感种群AH-7;抗性种群AFT对炔草酯、烯草酮、氟唑磺隆的抗性倍数分别为27.90、34.43、10.30,表现出高水平的抗性,对唑啉草酯、甲咪唑烟酸、双草醚的抗性倍数分别为5.49、6.42、5.01,表现出中等水平的抗性。经除草剂诱导后,植株体内基于GSTs代谢酶介导的代谢反应水平升高,加快植株对除草剂的代谢解毒反应;抗性种群AFT的ACCase基因和ALS基因中发生的氨基酸突变和GSTs活性的增强可能是其产生抗药性的重要原因。     

Oxidative homeostasis in oocyte competence for in vitro embryo development

The objective of this study was to evaluate the levels of reactive oxygen species (ROS) and glutathione (GSH) in oocytes from follicles of different diameters and their relevance in the in vitro production of embryos (IVPE). Bovine ovaries were aspirated according to the diameter of the follicle [2–8 (general), 4–8 (large), and 2 < 4 mm (small)]. The oocytes were evaluated for levels of ROS, GSH, in vitro maturation, and IVPE. Higher levels of ROS and GSH were observed (p < 0.05) in oocytes of the large group (85.6 ± 7.2 and 140.0 ± 9.6) followed by those in the general (81.1 ± 10.5 and 134.3 ± 7.8) and small (73.5 ± 10.1 and 125.0 ± 10.6) groups. However, the proportion of ROS/GSH did not differ (p > 0.05) between the general, large, and small groups. The maturation was higher (p < 0.05) in the large group (87.8 ± 3.0%) than in the small group (72.2 ± 5.8%), but both were similar (p > 0.05) to that in the general group (82.2 ± 2.5%), whereas the IVPE of the large group (57.3 ± 3.0%) was higher (p < 0.05) than those in the general (44.7 ± 4.4%) and small (34.0 ± 4.0%) groups. We report that oocytes from large follicles are more competent for IVPE, whereas higher levels of ROS and GSH appear to be correlated with oocyte competence, as long as oxidative homeostasis is retained.     

Hepatic endogenous defense potential of propolis after mercury intoxication

Exposure to mercuric chloride (HgCl₂; 5 mg kg^?1 body weight; i.p.) induced oxidative stress in mice and substantially increased lipid peroxidation (LPO) and oxidized glutathione (GSSG) levels, decreased the level of reduced glutathione (GSH) and various antioxidant enzymes in liver and also increased the activities of liver marker enzymes in serum. Therapy with propolis extract, a resinous wax‐like beehive product (200 mg kg^?1 orally, after mercury administration), for 3 days inhibited LPO and the formation of GSSG and increased the level of GSH in the liver. Release of serum transaminases, alkaline phosphatase, lactate dehydrogenase and γ‐glutamyl transpeptidase were significantly restored after propolis treatment. The activities of antioxidant enzymes, that is, superoxide dismutase, catalase, glutathione‐S‐transferase and glucose‐6‐phosphate dehydrogenase, were also concomitantly restored towards normal levels after propolis administration. These observations clearly demonstrate that propolis treatment augments antioxidant defense against mercury‐induced toxicity and provide evidence that propolis has therapeutic potential as a hepatoprotective agent.