表没食子儿茶素没食子酸酯对丙烯酰胺致小脑颗粒神经元氧化损伤的防护作用研究

目的探讨表没食子儿茶素没食子酸酯(EGCG)对丙烯酰胺(ACR)致小脑颗粒神经元(CGNs)损伤的保护作用。方法采用体外细胞培养的方法,建立ACR损伤CGNs的体外模型。经不同浓度EGCG(5、10、25、50、100 mol/L)预处理24h后,加入ACR(5 mmol/L)染毒,24 h后用四甲基偶氮唑盐(MTT)比色法检测细胞存活率,倒置显微镜下观察细胞形态学变化,测定细胞内超氧化物歧化酶(SOD)活性及丙二醛(MDA)的含量,Hochest 33342染色观察凋亡时细胞核形态的变化,末端脱氧核苷酸转移酶介导的原位缺口末端标记(TUNEL)法检测细胞凋亡指数。结果同ACR损伤组比较,终浓度为10、25、50 mol/L的EGCG能减轻ACR引起的CGNs损伤,可明显提高细胞的存活率(P<0.05),SOD活性增高,MDA含量降低(P<0.05),Hoechst33342染色和TUNEL荧光标记显示,细胞核固缩、致密浓染现象较ACR损伤模型组改善明显,凋亡指数下降(P<0.05),且呈现剂量依赖趋势,而终浓度为5、100 mol/L EGCG组较正常组无明显变化。结论 EGCG在一定剂量范围内对ACR氧化损伤的CGNs有防护作用。[营养学报,2012,34(4):362-367]

STUDY ON THE PROTECTIVE EFFECTS OF EPIGALLOCATECHIN-3-GALLATE ON OXIDATIVE DAMAGE IN RAT CEREBELLAR GRANULE NEURONS INDUCED BY ACRYLAMIDE

Objective To study the protective effect of epigallocatechin-3-gallate(EGCG) against the cerebellar granule neurons(CGNs) on oxidative damage induced by acrylamide(ACR).Methods CGNs were cultured and added with 5 mmol/L ACR for 24 h to set up the cell injury model.After treatment of CGNs with different concentrations of EGCG(5,10,25,50,100 μmol/L) for 24 h,5 mmol/L ACR was added to the cultures for 24 h respectively.The neuronal viability was measured by metylthiazolyltetrazolium(MTT),and the morphological observation of cerebellar granule neurons by Hoechst 33 342 staining under inverted phase-contrast microscope.The activity of SOD and the content of MDA were assayed,The ratio of apoptic cells was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling(TUNEL).Results At the concentrations of 10,25 or 50 μmol/L,the EGCG played protective role against ACR induced CGNs injury.Compared with ACR injury model group,EGCG improved the cell viability and SOD activity,decreased the level of MDA and the cell apoptosis ratio(P<0.05) dose-dependently.However,there was insignificant changes in 5 and 100 μmol/L EGCG groups.Conclusion EGCG at appropriate concentration has protective effect against the CGNs on oxidative damage induced by ACR.