籽瓜多糖对H_2O_2致PC12细胞氧化损伤的保护作用  

Protective Effects of Polysaccharide from Seed Watermelon on the Oxidative Damage of PC12 Cells Induced by H_2O_2

作　　者：刘琴[1,2,3] 宋珅[1] 郭杰[1] 罗顺 张继[1,2] 

机构地区：[1]西北师范大学生命科学学院 [2]甘肃特色植物有效成分制品工程技术研究中心 [3]甘肃万州健顺生物科技有限公司,兰州730070

出　　处：《天然产物研究与开发》2015年第2期338-343,366,共7页Natural Product Research and Development

基　　金：国家自然科学基金(31200255);国家科技支撑计划(2012BAD36B04)

摘　　要：本文研究了籽瓜多糖(SWP)对H2O2致PC12细胞氧化应激损伤的影响及其机制。通过建立H2O2诱导PC12细胞氧化损伤模型,CCK-8法测定细胞存活率;硫辛酰胺脱氢酶催化的INT显色反应检测乳酸脱氢酶(LDH)释放量,DCFH-DA检测细胞内ROS;ELISA法检测8-OHd G;JC-1染色检测细胞线粒体膜电位;利用caspase-3可以催化底物Ac-DEVD-p NA的反应检测caspase-3活性;应用caspase-9催化特异性底物Ac-LEHDp NA检测caspase-9活性。结果显示:过氧化氢组与对照组相比,终浓度为500μmol/L H2O2作用细胞24 h后,细胞活力显著下降(P<0.01);LDH释放量和细胞内ROS增加(P<0.01);8-OHd G含量上升(P<0.01);线粒体膜电位下降(P<0.01);caspase-3和caspase-9活性增强(P<0.01)。与H2O2损伤组相比,不同剂量的SWP预处理后,能显著改善H2O2引起的上述指标的变化(P<0.05)。由此得出:SWP对H2O2诱导的PC12细胞的氧化损伤具有一定的保护作用。To determine the neuroproteetive effects of seed watermelon polysaecharide on PC12 cells injured by H202 and the molecular mechanisms underlying these neuroprotective effects. The cell viability was analyzed by CCK-8 assay, the toxicity model was established by treating PC12 cells with H202. The releasing rate of LDH was determined by the color reaction of diaphorase INT. ROS production was determined by I）CFI-I-DA fluorescence. 8-OHdG production was deter- mined by ELISA. Mitochondfia membrane potential was determined by JC-1 staining. Caspase-3 activity was determined by caspase-3 catalyze the substrate specificity Ae-DEVD-pNA. Caspase-9 activity was determined by caspase-9 catalyze the substrate specificity Ac-LEHD-pNA. In comparison to control cells,exposure of cells to 500μmol/L H：O2 for 24 h resulted in approximately 65% cell viability of control （P 〈0.01 ）. H202 induced significantly the increase of LDH re- lease,intracellular ROS and 8-OHdG （P 〈 0.01 ）, and the decrease of mitochondfial membrane potential （ P 〈 0. 01 ）. H2 O2 induced oxidative stress increased caspase-3 and caspase-9 activity （P 〈 0.01 ）. Compared with H202 group, dif- ferent doses of SWP can significantly improve the change of the index H20：indueed （P 〈 0.05 ）. Polysaccharide from seed watermelon had protective effect on PC12 cells injury induced by H202 in culture.

关 键 词：籽瓜多糖 过氧化氢 氧化损伤 CASPASE PC12细胞 

分 类 号：R285[医药卫生—中药学]