还原型谷胱甘肽对氟中毒小鼠附睾的影响

试验旨在研究还原型谷胱甘肽（reduced glutathione,GSH）对氟中毒小鼠附睾的影响。将50只3周龄ICR雄性小鼠随机分为5组,分别为对照组和4组染氟组。对照组饮用蒸馏水,染氟组分别供给含100 mg/L NaF的蒸馏水,自由饮水30 d。之后在染氟组中选择3组每日分别灌胃200、400和800 mg/（kg·只）GSH,同时各组小鼠再自由饮含氟水30 d。试验结束后,摘取小鼠附睾进行活性氧（ROS）、丙二醛（MDA）、GSH含量及谷胱甘肽过氧化物酶（GPx）、谷胱甘肽硫转移酶（GSTs）和谷胱甘肽还原酶（GR）活性检测,同时制作石蜡切片,HE染色后进行组织形态结构分析。结果显示,与对照组相比,100 mg/L NaF组精子密度、精子活力、GSH含量、GPx和GR活性均显著下降（P<0.05）,而GSH添加组较100 mg/L NaF组均有所升高;100 mg/L NaF组精子畸形率、ROS和MDA含量较对照组均显著升高（P<0.05）,而GSH添加组较100 mg/L NaF组均降低,其中800 mg/kg GSH组效果明显。与对照组相比,100 mg/L NaF组附睾头、附睾体及附睾尾管腔厚度升高,管腔内精子数量下降;GSH添加组附睾头、附睾体及附睾尾的管腔厚度与管腔内精子数量都有所恢复,其中800 mg/kg GSH组效果较好。综上所述,添加GSH后氟中毒小鼠谷胱甘肽抗氧化系统酶活性有所升高,附睾组织形态结构一定程度上有所恢复,对附睾有一定的改善作用。     

Effects of the herbicide LASSO MTX (alachlor 42% W/V) on biometric parameters and liver biomarkers in the common carp (Cyprinus carpio)

The aim of the study was to evaluate the effect of subchronic exposure to the herbicide LASSO MTX (alachlor 42% W/V) on biometric parameters and important liver biomarkers in the common carp (Cyprinus carpio). One year old fish were exposed for 28 days to LASSO MTX added to the tank water at concentrations of 240 and 2400 μg L⁻¹. The exposure did not affect fish biometric parameters. Glutathione-S-tranferase (GST) activity in liver (hepatopancreas) remained unchanged in exposed fish when compared to controls. However, significant induction of total cytochrome P 450 (CYP 450), ethoxyresorufin-O-deethylase (EROD) activity and elevated glutathione (GSH) in liver of exposed fish were detected.     

BTH-mediated antioxidant system responses in apple leaf tissues

BTH (S-methylbenzo-1,2,3-thiadiazole-7-carbothiate), an active compound of the commercial preparation Bion, has been studied as an elicitor of resistance to fire blight (Erwinia amylovora) in apple. However, the biochemical mechanisms of its action are not fully elucidated. Our study indicated that BTH at the best time of its protection activity (2–14 days after application) induced changes in prooxidant–antioxidant balance in the leaves of apple trees, but in different ways in the enzymatic and nonenzymatic antioxidants. Glutathione as low molecular antioxidant as well as superoxide anion radical and lipid peroxides as oxidants exhibited changes at the early phase of BTH action. Glutathione-dependent enzymes were strongly affected by the elicitor used. On the 2nd day glutathione transferase (GST) and glutathione peroxidase (GSH-Px) activities increased by about 70% and 30% above the control, respectively. GST activity normalized about the 14th day but GSH-Px at the same time showed 27% of the control value. Among enzymes utilising hydrogen peroxide only catalase showed increase (37%) at the early phase of experiment. Compared with the control, BTH-treated plants did not show changes in ascorbate peroxidase and phenylalanine ammonia-lyase activities. Tocopherol (TOC) level diminished starting from the 7th day after BTH treatment and on the 14th day it was only 28% of the control. It is proposed that extinguishing of BTH-mediated signal resulted from TOC and glutathione action. The diminished ascorbate level at all examined times may play a crucial role in BTH-mediated cell growth regulation. The direct influence of BTH on lipid metabolism should be also taken into consideration.     

Effect of methyl parathion and chlorpyrifos on certain biomarkers in various tissues of guppy fish, Poecilia reticulata

Tests of acute toxicity were performed on the most common species of aquarium fish, Poecilia reticulata. Guppies (P. reticulata) were exposed to progressive concentrations of methyl parathion (MP) and chlorpyrifos (CPF); a semi-static method according to guidelines of OECD was used. Tests of acute toxicity were conducted using 10 fish for each separate concentration and for the control group. The results were subjected to probit analysis to determine the 96 h LC₅₀ values. The 96 h LC₅₀ values of MP and CPF to P. reticulata were 8.48 ppm/L (5.98–10.89) and 0.176 ppm/L (0.313–0.224) respectively. In addition, behavioral changes at each concentration were observed for the individual fish. Fish were exposed for 96 h to different sublethal concentrations of MP and CPF (¼ LC₅₀, 1/8 LC₅₀ and 1/10 LC₅₀) and their oxidative stress-induction potential was estimated in brain, liver and gills of fish. MDA content is induced in all tissues but maximum rise was observed in gills (161% and 153% for MP and CPF respectively). With regard to antioxidant defense system (ADS), GSH level decreased in the brain, liver and gills of tissues of MP treated fishes (22%, 6% and 13% respectively) and showed increase in brain and gills CPF treated (23% and 21% respectively). CAT, GST, GR and SOD levels fluctuated in all treatment groups relative to the control. Brain AChE showed dose-dependent inhibition in fish exposed to the higher concentrations reached 45% and 66% for MP and CPF respectively. Collective findings demonstrated that pesticide exposure of fish induced an increase in MDA and fluctuated ADS along with inhibited AChE. These findings may be used as valuable biomarkers for evaluation of water pollution.     

谷胱甘肽对切花月季‘Samantha’失水胁迫耐性的影响

采用外源谷胱甘肽（GSH）及其生物合成关键酶γ–谷氨酰半胱氨肽合成酶（γ-ECS）的专一抑制剂丁胱亚磺酰胺（BSO）分别处理切花月季‘Samantha’花枝基部,以提高或降低花瓣中的GSH含量,研究GSH对月季切花失水胁迫耐性的影响,以及花瓣中抗坏血酸–谷胱甘肽（AsA-GSH）循环对失水胁迫的响应。结果表明：提高花瓣中GSH的含量,明显提高了失水胁迫24 h后切花的复水率,延长了瓶插寿命;相反,BSO预处理降低了花瓣中的GSH含量,从而降低了切花的失水胁迫耐性。GSH预处理在明显提高失水胁迫和复水期间花瓣中GSH总含量和还原型GSH含量的同时也提高了抗坏血酸（AsA）的含量;AsA-GSH循环中两个关键酶抗坏血酸过氧化物酶（APX）和谷胱甘肽还原酶（GR）的活性也明显高于胁迫对照,并且MDA的含量明显降低。BSO预处理则产生相反的效果。这些结果表明,GSH能够通过提高AsA-GSH循环的抗氧化能力来增强月季切花的失水胁迫耐性。     

GSH与ASA对牡丹花瓣生理生化的调控研究

以不同浓度的谷胱甘肽(GSH)+抗坏血酸(ASA)水溶液对牡丹"似荷莲"品种花蕾期进行全株喷雾处理,测定了整个花期花瓣中可溶性糖、可溶性蛋白含量,超氧化物歧化酶(SOD)活力、超氧阴离子(O2-)产生速率和丙二醛(MDA)含量的变化。结果表明:不同浓度GSH+ASA组合均能提高牡丹花瓣中SOD活力、可溶性蛋白和可溶性糖含量,降低花瓣中O2-产生速率和MDA含量,其中以GSH100 mg/L+ASA100 mg/L处理效果最佳。     

安全剂R-28725保护玉米免受氯嘧磺隆药害的机理研究

研究了安全剂R-28725对玉米的保护作用及对氯嘧磺隆的解毒机理。当氯嘧磺隆的使用量为5、10、15 g/hm2时,加入R-28725能够明显提高玉米株高、株鲜重和产量,直接增加玉米体内谷胱甘肽(GSH)含量,增加氯嘧磺隆与谷胱甘肽的轭合,从而达到解毒的目的。     

EGF和GSH对牛卵母细胞体外受精的影响

研究了牛卵泡卵母细胞体外受精时向成熟液中加入EGF(表皮生长因子),受精液中加入GSH(谷胱甘肽)对受精率和囊胚率的影响。成熟液以M-199为基础液并加入一定浓度的促性腺激素和OCS,作为成熟液的对照组,试验组加入不同浓度的EGF。受精液以改良TALP为基础液并加入一定浓度的BSA、肝素和咖啡因,作为受精液的对照组,试验组加入不同浓度的GSH。早期胚胎培养液为SOFaa。在成熟液中加入10ng/mlEGF和50ng/mlEGF组时,试验组与对照组的受精率分别为76.00%(114/150)、76.71%(112/146)和60.70%(85/140);囊胚率分别为23.68%(27/114)、24.11%(27/112)和17.64%(15/85);在受精液中加入1mMGSH和10mMGSH组时,试验组与对照组的受精率分别为71.66%(86/120)、63.28%(81/128)和76.00%(114/150);囊胚率分别为34.88%(30/86)、24.69%(20/81)和23.68%(27/114)。结果表明,成熟液中加入EGF对牛卵母细胞的体外成熟和受精后的早期胚胎的发育都有促进作用,在一定范围内增加EGF浓度,不会提高受精率和囊胚率;受精液中加入一定浓度GSH能够提高受精率和囊胚率,但是在高浓度的GSH时则影响受精率。     

谷胱甘肽提高月季切花失水胁迫耐性与GR活性的关系

 本研究确定了切花月季‘Samantha’预处理采用的谷胱甘肽(GSH) 及其生物合成抑制剂丁胱亚磺酰胺〔L-buthione (S, R) sulfoximine, BSO〕适宜浓度, 探讨了GSH和BSO预处理对花朵水势、花瓣中MDA含量、GSH含量以及GR活性等的影响。结果表明: 与失水胁迫对照处理相比较, 2 mmol/L GSH预处理明显提高了月季切花瓶插期间花朵水势, 显著降低了花瓣中MDA含量, 有效提高了花瓣中GSH含量和GR活性。2 mmol/L BSO预处理获得了理想的反证结果。结果说明, GSH对切花月季‘Samantha’失水胁迫耐性的改善与花瓣中GR活性的提高相联系。     

谷胱甘肽处理对采后鸭梨果实黑心病和抗氧化代谢的影响

谷胱甘肽(GSH)是一种重要的抗氧化剂。鸭梨果实经过负压渗透GSH后,并经缓慢降温最终贮存于0℃和80%￣90%的相对湿度(RH)条件下。结果表明,GSH能有效抑制鸭梨果实在低温贮藏6个月后黑心病的发生,处理果的黑心率及黑心指数分别比对照果降低了26.9%和37.1%。GSH处理的果实在贮藏过程中较对照具有较低的丙二醛含量,处理后果实中抗坏血酸、GSH含量以及超氧化物歧化酶、过氧化氢酶活性也明显高于对照果,抗坏血酸过氧化物酶较对照提前出现活性高峰,而谷胱甘肽还原酶的变化不明显。GSH处理对鸭梨果实黑心病的抑制作用可能与其增强了果实的抗氧化能力有关。