双甲脒对BRL 3A细胞的毒性作用

为了探讨双甲脒对BRL 3A细胞的毒性作用,本试验以0、20、40、60μmol/L的双甲脒分别处理BRL 3A细胞,MTT法检测细胞的相对活力,同时测定细胞培养上清液中细胞乳酸脱氢酶的活性,测定细胞内超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶和细胞内谷胱甘肽还原酶的活性以及还原型谷胱甘肽和活性以及丙二醛的含量。结果表明,与对照组相比,随着双甲脒浓度的升高,细胞活性显著或极显著下降(P0.05或P0.01),细胞培养上清液中LDH活性和细胞内GSH-Px、SOD、CAT的活性显著或极显著升高(P0.05或P0.01),MDA和GSH的含量增加,但差异不显著(P0.05),GR活性先升高后降低,差异显著或极显著(P0.05或P0.01)。结果表明,双甲脒对细胞有明显的毒性,并且氧化应激在其中起到了重要作用。     

细胞凋亡的主要检测方法研究进展

细胞凋亡是生理性细胞死亡过程,凋亡在维持动物机体内环境平衡中扮演着极其重要的角色.细胞凋亡的准确检测是研究细胞凋亡相关机制,以及评价细胞凋亡在相应组织或疾病中影响的第一步.形态学是检测细胞凋亡的最直观的方法,至今一直作为细胞凋亡检测的金标准.DNA片段化检测主要有DNA ladder,TUNEL检测法和ELISA检测法...     

Cr3+、Cr6+对鼠肺细胞线粒体膜电位改变及活性氧生成的研究

铬主要以Cr^3 和Cr^6 的形式广泛存在于环境中，其对人或动物的生物效应与其价态有关。本实验用荧光染料罗丹明123和二乙酰二氯氢化荧光素测定细胞内的活性氧和线粒体膜电位，比较Cr^3 和Cr^6 对中国仓鼠肺细胞的毒性作用。发现Cr^3 未引起细胞活性氧生成增加和线粒体膜电位的下降，而Cr^6 可导致细胞活性氧生成增加和线粒体膜电位的下降。提示线粒体可能是Cr^6 所致氧化损伤的靶器官之一，而Cr^6 所致氧化损伤可能是由其诱导产生的ROS介导，而不是由Cr^3 介导。     

甘草乙醇提取物对猫肾脏细胞的毒性研究

甘草常见于一些处方猫粮的配方中,但其对猫肾脏毒性作用尚无研究。本研究分析了甘草乙醇提取物的主要成分,并通过细胞模型分析了提取物对猫肾脏细胞CRFK的毒性作用。结果表明,甘草乙醇提取物中多糖含量较高,在24 h作用时间内,高浓度提取物(≥200μg/mL)对猫肾脏细胞CRFK细胞活力、中性红吞噬能力有抑制作用,能显著降低贴壁细胞的总蛋白含量,低浓度(50μg/mL)提取物对CRFK细胞活力无显著影响;50μg/mL甘草提取物长期作用(96 h)对CRFK细胞活力有显著促进作用。研究提示,家猫长期采食含有适当量甘草的处方粮不会对其造成肾脏毒性,但需要进一步体内研究验证。     

拉合尔钝缘蜱对宿主细胞的遗传毒性研究

拉合尔钝缘蜱对宿主细胞的遗传毒性研究陆家海，程维兴，胡边，李德昌，郭固（兰州军区乌鲁木齐总医院）蜱（Ｔｉｃｋｓ）是人和动物的吸血外寄生虫，除直接吸血引起人畜贫血和麻痹外，还可传播森林脑炎、新疆出血热、Ｑ热、蜱传斑疹伤寒、泰勒焦虫病等［１，２，３］。近...     

4种因素对NK细胞杀伤活性的影响

为了探讨效应细胞与靶细胞的比例(效靶比)、孵育时间、显色时间以及小牛血清浓度对NK细胞杀伤活性的影响,采用乳酸脱氢酶释放法来测定不同因素对NK细胞杀伤活性的影响,结果表明,最佳效靶比和孵育时间分别为50∶1和2 h。在最优效靶比及孵育时间的基础上,显色0.5 h,小牛血清浓度为50 mL/L时NK细胞活性最高,证明4种因素对NK细胞杀伤活性均有不同程序的影响。     

黄芪乙醇粗提物对猫肾细胞毒性的研究

为研究黄芪乙醇粗提物对猫肾(Crandell-Rees Feline Kidney, CRFK)细胞的毒性,利用50%(体积分数)乙醇,超声(50℃,280 W)提取黄芪粉末,制得黄芪乙醇粗提物(简称“粗提物AME”);在初步分析粗提物AME的3类组成物质含量基础上,测定在不同质量浓度粗提物AME作用下的CRFK细胞活力、中性红吞噬能力及裂解液总蛋白质量浓度,并分析了粗提物AME对过氧化氢处理(氧化诱导)的细胞活力及总氧自由基水平的影响。研究结果显示：粗提物AME中多糖、总多酚和总蛋白质量分数分别为(53.07±1.73)%、(13.80±0.78)%和(0.13±0.01)%;在作用96 h内,高质量浓度粗提物AME(2 000μg/mL)使CRFK细胞活力降低,低质量浓度粗提物AME(50～1 000μg/mL)使CRFK细胞活力增强;粗提物AME添加质量浓度≥500μg/mL时,CRFK细胞中性红吞噬率降低,CRFK细胞裂解液总蛋白质量浓度也显著降低;50～2 000μg/mL的粗提物AME对由过氧化氢诱导的CRFK细胞活力下降具有显著抑制作用,且对胞内总氧自由基具有清除作用。     

硫酸黏菌素对原代背根神经元细胞的毒性作用

建立了新生小鼠原代背根节(Dorsal root ganglion,DRG)神经元细胞原代培养的方法,作为评价硫酸黏菌素毒性的体外研究模型.在此模型基础上,使用不同浓度的硫酸黏菌素作用细胞24h后,应用MTT方法观察细胞毒性效应并测定细胞半数抑制浓度(IC50).结果表明,不同浓度硫酸黏菌素处理细胞后,高剂量组DRG神经元细胞出现明显病变,硫酸黏菌素浓度低于10μg/mL时,对DRG神经元细胞存活率无明显影响,硫酸黏菌素浓度达到10μg/mL以上时,细胞存活率降低,出现细胞毒性,且毒性作用强度随药物浓度增加而增强;试验测得硫酸黏菌素对DRG神经元的半数抑制浓度(IC50)为222.7μg/mL.     

鸡血藤总黄酮对脂多糖刺激RAW264.7细胞氧化应激的调节作用

采用乙醇提取法提取得到鸡血藤总黄酮(FSSD),MTT法分析其细胞毒性,并探讨其预处理和后处理对脂多糖(LPS)刺激RAW264.7细胞所致氧化应激的影响。试验一先用不同浓度的FSSD(25、50和100μg/m L)处理细胞12 h,再用LPS进行刺激,诱导氧化应激的产生;试验二先用LPS刺激细胞2 h,然后用不同浓度FSSD处理细胞8 h。分别采用Griess法和荧光探针法检测NO和活性氧(ROS)水平。研究发现,FSSD预处理和后处理均能抑制LPS刺激引起的NO和ROS水平的升高(P0.05),且后处理效果更明显。因此,FSSD具有良好的抗氧化应激活性,且用做治疗药物效果更明显。     

黄藤素对山羊子宫内膜上皮细胞的体外毒性研究

为了探究黄藤素的体外细胞毒性,采用不同浓度的黄藤素作用山羊子宫内膜上皮细胞（EECs）后,采用MTT法绘制细胞生长曲线;倒置显微镜下观察细胞生长状态;瑞氏-姬姆萨染色法观察细胞形态学变化并通过测定乳酸脱氢酶（LDH）含量检测细胞膜的完整性。结果显示,当黄藤素的浓度为10~227 μg/mL时,黄藤素对EECs有促增殖的作用;当浓度大于227 μg/mL时出现细胞增殖抑制现象,药物对细胞的半数增殖抑制率（IC₅₀）为360 μg/mL;瑞氏-姬姆萨染色结果显示,100、200 μg/mL的黄藤素作用于EECs时均未对其细胞核、细胞浆的形态产生影响;LDH结果显示,药物浓度≥250 μg/mL时细胞LDH的释放量极显著高于正常细胞组（P<0.01）。综上所述,黄藤素作用于山羊EECs后呈现一定的毒性作用,且呈现显著的剂量依赖效应,作用于EECs的安全剂量范围为≤250 μg/mL。     

The Study on the Cytotoxicity of Palmatine on Goat Endometrial Epithelial Cells in vitro

To explore the cytotoxicity of palmatine in vitro,goat endometrial epithelial cells (EECs) were stimulated by different concentrations of palmatine,then the growth curve of cell was drew by MTT assay which could detect the cell proliferation. The cell growth state was observed by inverted microscope,and Wright-Giemsa staining was used to observe morphological changes of the cells while LDH test was used to check the membrane permeability of EECs. The results showed that when the concentration was 10 to 227 μg/mL,palmatine had a role in promoting proliferation of the EECs,while when the concentration was more than 227 μg/mL,cell proliferation was inhibited,and 50% inhibitory rate of proliferation (IC₅₀) of this drug on EECs was 360 μg/mL.Wright-Giemsa staining results showed that themorphology of the nucleus and cytolymph were not significantly changed when 100 and 200 μg/mL palmatine effected EECs. LDH results showed that when the palmatine concentration was more than 250 μg/mL,LDH content was extremely significantly higher than that of normal cell group(P<0.01).In conclusion,palmatine presented certain toxic effect on EECs with a significant dose-response effect,and the safe dose range of palmatine was less than 250 μg/mL.     

辣木叶多糖对过氧化氢诱导奶牛乳腺上皮细胞氧化损伤的保护作用

奶牛乳腺上皮细胞(BMECs)在奶牛泌乳期代谢旺盛,导致活性氧(ROS)大量产生,从而诱发氧化应激.辣木叶多糖(MLP)能有效清除ROS和自由基,但其是否具有缓解BMECs氧化损伤的潜力尚不清楚.因此,本文以MLP为添加剂,探究其对过氧化氢(H2O2)诱导BMECs氧化损伤的保护作用.本试验首先将分离的BMECs置于含...     

Cytotoxicity of gamma-ray in rat immature hippocampal neurons

This in vitro study evaluated the detrimental effect of acute gamma (γ)-irradiation on rat immature hippocampal neurons. Rat immature hippocampal neurons (0.5 day in vitro) were irradiated with 0~4 Gy γ-rays. Cytotoxicity was analyzed using a lactate dehydrogenase release assay at 24 h after γ-irradiation. Radiation-induced cytotoxicity in immature hippocampal neurons increased in a dose-dependent manner. Pre-treatments of pro-apoptotic caspase inhibitors and anti-oxidative substances significantly blocked γ-irradiation-induced cytotoxicity in immature hippocampal neurons. The results suggest that the caspase-dependent cytotoxicity of γ-rays in immature hippocampal cultured neurons may be caused by oxidative stress.     

热应激条件下机体发生氧化应激的机制

热应激是指机体在高温条件下对热暴露所做出的非特异性生理反应的总和。有研究表明热应激会引起机体氧化还原平衡紊乱,发生氧化应激,损伤细胞和组织,从而影响机体的生长发育及健康状况。热应激一直都是国内外研究的热点,随着全球气温的上升,热应激问题将会更加突出,本文就热应激条件下氧化应激发生的机制作一综述,以期为后续的相关研究提供参考。     

Effect of freezing bull semen in two non‐egg yolk extenders on post‐thaw sperm quality

Traditionally, extenders for bull semen included egg yolk or milk, but recently there has been a move to avoid material of animal origin. The aim of this study was to evaluate the effects of two commercial extenders (based on soya lecithin and liposomes) on bull sperm quality after cryopreservation. Post‐thaw sperm quality was evaluated by computer‐assisted sperm analysis and flow cytometric assessment of membrane integrity, chromatin integrity, mitochondrial membrane potential, production of reactive oxygen species and tyrosine phosphorylation. Furthermore, an artificial insemination (AI) trial was conducted, and 56‐day non‐return rates were evaluated. Semen frozen in the liposome‐based extender showed similar membrane integrity and higher mitochondrial membrane potential compared to those in the soya lecithin‐based extender. Chromatin integrity and production of live H₂O₂+ reactive oxygen species were similar in both extenders. Less superoxide was produced in the samples extended with liposome‐based extender, with or without menadione stimulation. Chromatin integrity and tyrosine phosphorylation were not affected by either type of extender. No differences in 56‐day non‐return rate between extenders containing soya lecithin and liposomes were observed in the AI trial (66% ± 0.8 and 65% ± 0.8, respectively). In conclusion, the sperm quality of bull semen frozen in the two extenders that do not contain material of animal origin was similar, although the semen frozen in the liposome‐based extender had higher mitochondrial membrane potential. Either extender could be used in situations where extenders containing material of animal origin are to be avoided.     

藏药绿萝花水提物对成纤维细胞线粒体抗氧化作用的研究

为探讨不同浓度的绿萝花制剂对线粒体的抗氧化作用及毒理作用,以小鼠胚胎成纤维细胞及其线粒体为研究对象,在最大无毒作用浓度(TC_0)的基础上设计3个浓度药物组,在TC_0下设计6个浓度药物组,以成纤维细胞线粒体膜电位(MMP)和线粒体总活性氧含量(ROS)为检测指标,在4个不同作用时间点,研究绿萝花对成纤维细胞线粒体的影响。结果表明,绿萝花制剂对鼠胚成纤维细胞(MEF)的TC_0为0.25g/mL,但ROS已急剧上升,MMP下降;绿萝花浓度为0.03g/mL时,抗氧化能力最强,随着浓度的上升(0.03g/mL~0.25g/mL),线粒体抗氧化能力减弱或消失;随着给药浓度的升高,细胞凋亡现象出现趋势明显,浓度高于TC_0时,表现出毒性作用,浓度升高,毒性增大。绿萝花干膏制剂0.03g/mL(以生药含量计算)具有抵抗由H_2O_2引起的MEF线粒体MMP下降和ROS的升高的功能,表现出一定的抗氧化能力和阻滞细胞凋亡发生的作用;TC_0及之上浓度具有细胞毒性作用。     

Accumulation of lipofuscin in broiler chicken with wooden breast

Lipofuscin is one of the indicators of oxidative stress. To elucidate the role of oxidative stress in the development of wooden breast, this study investigates lipofuscin accumulation in various parts of wooden breast muscles. Sampling was performed using 46-day-old broiler chickens housed at a commercial Japanese poultry slaughterhouse. Fourteen wooden breast fillets and 13 normal breast fillets were collected in the deboning line. The samples used to measure shear force, 2-thiobarbituric acid reactive substance (TBARS), and for histological analysis were taken from the six portions of breast muscle fillets. In muscles affected by wooden breast, vacuolated muscle fibers were observed, and connective tissues appearing like perimysium were expanded with fibrosis. TBARS value and accumulation of lipofuscin were significantly higher in the wooden breast than in the normal breasts. A lot of lipofuscin granules were localized in the cytoplasm of collapsed muscle fibers of the wooden breast. The cranial portion of the wooden breast showed the highest shear force. The cranial position had a large amount of connective tissue and lipofuscin granules. The results of the present study strongly suggest that high oxidative stress, especially with a significant accumulation of lipofuscin, is associated with the development of wooden breasts.     

氧化应激的产生及其对畜禽肝脏功能的影响与机制

现代畜牧业规模化生产中,养殖环境、饲粮构成、饲养方式等诸多因素变化可诱发畜禽产生氧化应激。氧化应激对畜禽的肝脏功能有负面作用,危害畜禽健康和生产。机体发生氧化应激时,大量的氧自由基在肝细胞内蓄积,通过损伤生物大分子物质、破坏肝细胞结构、影响细胞器功能、诱发肝细胞凋亡等,对肝脏造成严重损伤,并引发多种肝脏疾病。本文从机体氧化应激产生、氧化应激对肝脏功能的影响以及氧化应激影响肝脏功能的可能分子机制等方面进行综述,以期为缓解氧化应激危害提供理论依据。     

附睾精子抗氧化保护机制研究进展

通过附睾转运,精子经历了一系列的生化和形态变化逐渐成熟,在精子成熟的过程中,其胞质成分含量逐渐减少,因此精子对氧化应激更为敏感,进而导致精子结构和功能受到损害,故而附睾管腔微环境中抗氧化酶的作用非常重要。活性氧(ROS)在精子功能中起着双重作用:生理水平的ROS可促进精子受精前的获能,而过高水平ROS则会导致精子发生氧化损伤。在附睾中清除多余ROS的抗氧化酶主要有超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPXs)以及过氧化物酶(PRDXs),但是不同年龄的哺乳动物附睾不同部位中各种抗氧化酶的含量均会发生变化,不同抗氧化酶对ROS也具有不同的清除机制。当附睾缺乏某一抗氧化酶时,会使精子DNA受损、精子质量下降,最终导致异常生殖结果增加。因此,哺乳动物附睾中各类抗氧化酶需要相互协调将ROS维持在生理水平,但有关这方面的研究报道较少。附睾上皮细胞分泌的抗氧化酶以附睾小体的形式传递给精子,以清除自身有氧代谢以及异常精子所产生的ROS,进而保护精子正常成熟。作者综述了附睾精子所面临的氧化应激以及附睾中各类抗氧化酶对精子的保护作用。