桑椹提取物对β-淀粉样蛋白致PC12细胞损伤保护作用的初步研究  

Primary study on protective effect of mulberry extracts on Aβ_(25-35)-induced PC12 cells injury

作　　者：宋楠[1] 庞伟[2] 杨红澎[3] 谭龙[2] 傅经明[2] 李海强[2] 蒋与刚[2] 

机构地区：[1]广西医科大学公共卫生学院营养与食品卫生学教研室,南宁530021 [2]军事医学科学院卫生学环境医学研究所 [3]天津农学院

出　　处：《卫生研究》2012年第6期925-929,共5页Journal of Hygiene Research

基　　金：国家自然科学基金(No.30872098,30901185);天津市应用基础及前沿技术研究计划(No.09JCYBJC12900)

摘　　要：目的观察桑椹提取物(ME)对β-淀粉样蛋白(Aβ25-35)致PC12细胞损伤的保护作用,并初步探讨相关机制。方法将细胞分为对照组(未加任何处理因素)、Aβ25-35组(20μmol/L Aβ25-35损伤24h)以及(25、50、100、200、400和800μg/ml)ME预孵育组(ME预孵育24h后再给予20μmol/L Aβ25-35继续损伤24h),采用MTT法确定ME的干预浓度。在此基础上,将细胞分为对照组(未加任何处理因素)、ME组(200μg/ml ME作用24h)、Aβ25-35组(20μmol/L Aβ25-35损伤24h)以及ME预孵育+Aβ25-35组(200μg/ml ME预孵育24h后再给予20μmol/L Aβ25-35继续损伤24h),采用分子探针DCFH-DA及Hoechst33342染色法分别进行细胞内活性氧(ROS)含量及细胞凋亡的测定。结果 (1)与对照组相比,Aβ25-35组细胞存活率显著降低(P<0.05);与Aβ25-35组相比,100、200μg/ml ME预孵育组细胞存活率显著提高(P<0.05)。(2)与对照组相比,200μg/ml ME组细胞ROS的生成及细胞凋亡率无显著变化(P>0.05),而Aβ25-35组细胞内ROS的生成显著升高(P<0.05)、细胞凋亡率也明显增加(P<0.05);与Aβ25-35组相比,200μg/ml ME预孵育组细胞内ROS的生成显著减少(P<0.05)且细胞凋亡率明显降低(P<0.05)。结论桑椹提取物对Aβ25-35致PC12细胞损伤有明显的保护作用,机制与其抗氧化及抑制凋亡作用有关。Objective To investigate the neuroprotective effect of mulberry extracts（ME） against Aβ25-35-induced injury in cultured PC12 cells and explore the possible mechanisms involved.Methods PC12 cells at logarithmic growth phase were divided into the normal control group,Aβ25-35 group（20μmol/L for 24h） and ME pretreating groups at the concentrations of 25,50,100,200,400,800μg/ml.Cell viability was determined by MTT assay.On that basis,PC12 cells were divided into the normal control group,ME group（200μg/ml ME incubation alone for 24h）,Aβ25-35 group（20μmol/L for 24h） and ME plus Aβ25-35 group（after pretreatment with 200μg/ml ME for 24h,cells were exposed to 20μmol/L Aβ25-35 for another 24h）.Intracellular reactive oxidative species（ROS） was measured by using the fluorescent DCFH-DA and the apoptotic cells were observed by Hoechst33342 staining method.Results（1） The results showed that exposure of PC12 cells to Aβ25-35（20μmol/L） for 24h induced notably neuronal injury（P〈0.05） as compared with the control group,while pretreatment with 100 or 200μg/ml ME almost completely reversed Aβ25-35 induced neuronal injury（P〈0.05）.（2） There were no remarkable changes in ROS levels and apoptosis rate of ME group as compared with the control group（P〈0.05）.Compared with the control group,exposure to 20μmol/L Aβ25-35 for 24h resulted in a significant decrease in cell viability（P〈0.05） while increase in ROS levels and cell apoptosis rate（P〈0.05）.But pretreatment of PC12 cells with 200μg/ml ME could counteract ROS formation and inhibit apoptosis（P〈0.05）.Conclusion These results suggest that mulberry extracts rich in phenolics and anthocyanins could alleviate Aβ25-35-induced injury in PC12 cells,which might be associated with the antioxidative and antiapoptosis effects.

关 键 词：桑椹提取物 PC12细胞 Β-淀粉样蛋白 氧化应激 凋亡 

分 类 号：Q946.91[生物学—植物学] Q226