EGCG和PC-B_2联合用药对AFB_1致肝细胞损伤的保护作用及其机制  

Protective Mechanism of Epigallocatechin Gallate( EGCG) and Procyanidins-B_2(PC-B_2) on Liver Cell from AFB_1-induced DNA Damage

作　　者：贾亮[1] 肖德强[1] 马玲玲[1] 范秋玉[1] 刘丹丹[2] 邓祥发[3] 黄东萍[3] 张勇胜[3] 鲁力[1] 

机构地区：[1]广西医科大学公共卫生学院,南宁530021 [2]广西医科大学护理学院,南宁530021 [3]广西医科大学基础医学院,南宁530021

出　　处：《中国实验方剂学杂志》2016年第2期113-117,共5页Chinese Journal of Experimental Traditional Medical Formulae

基　　金：国家自然科学基金项目(31360383)

摘　　要：目的:探讨多酚类植物化学物表没食子儿茶素没食子酸酯(EGCG)与原花青素B2(PC-B2),对黄曲霉素B1(AFB1)起的肝细胞损伤保护作用及机制。方法:选用人胚肝细胞(L-02细胞)进行体外实验研究,实验分为6组,分别为空白组,溶剂对照组,AFB_1染毒组,AFB_1染毒+EGCG组,AFB_1染毒+PC-B_2组和AFB_1染毒+EGCG+PC-B_2组。采用MTT检测细胞存活度,通过单细胞凝胶电泳试验(SCGE)检测细胞DNA损伤,通过流式细胞法检测细胞凋亡,采用Western blot法检测凋亡信号通路相关蛋白B细胞淋巴瘤/白血病-2(Bcl-2),Bcl-2相关X蛋白(Bax),半胱氨酸天冬氨酸蛋白酶-3(Caspase-3),Caspase-9,p53蛋白表达的水平。结果:EGCG与PC-B_2均能降低AFB_1所致L-02细胞的生长抑制,使AFB_1对肝细胞的生长抑制率从61.12%降至42.18%和46.72%;EGCG与PC-B_2联用则效果更佳。SCGE实验结果表明EGCG与PC-B_2单用与联用均能减小AFB_1引起的L-02细胞DNA损伤(P<0.05)。EGCG与PC-B_2单用与联用均能显著降低AFB_1所致L-02细胞的早期凋亡率(P<0.05)。Western blot实验结果表明,AFB_1染毒后,EGCG和/或PC-B_2处理均能显著降低Caspase-3,Caspase-9的表达(P<0.01),提高Bcl-2/Bax比值,而对p53表达影响不明显。结论:EGCG与PC-B_2通过降低L-02细胞DNA损伤与细胞凋亡率,从而降低AFB_1对人肝细胞的损伤作用,其作用机制可能与下调Caspase-3,Caspase-9的表达,升高Bcl-2/Bax有关。Objective： To evaluate the protective effects of（-）-epigallocatechin gallate（EGCG）combined with procyanidins B2（PC-B2） on liver cell damage caused by aflatoxin B_1（AFB1）. Method： L-02 cells were selected in an experimental study in vitro and divided into 6 groups： control group; solvent control group; AFB1 group; EGCG ＋ AFB1 group; PC-B2＋ AFB1 group; EGCG ＋ PC-B2＋ AFB1 group. The cells survival was determined by MTT; DNA damage was detected by single cell gel electrophoresis（SCGE）; the flow cytometry method was used to detect cell apoptosis; and the expressions of protein about apoptosis signaling pathways（Bcl-2,Bax,Caspase-3,Caspase-9,P53） were detected with Western blot method. Result： EGCG and PC-B2 can reduce liver cell growth inhibition caused by AFB1 from 61. 12% to 42. 18% and 46. 72%; EGCG combined with PC-B_2 made a better effect. SCGE results showed that either EGCG or PC-B2 can reduce liver cell DNA damage caused by AFB1. Simple or combined administration of EGCG and PC-B2 can decrease the early apoptosis rate of L-02 cells induced by AFB1（P〈0. 05）. Western blot experiments showed that after treatment with AFB1,EGCG or（and）PC-B2 treatment can reduce the expression of Caspase-3 and Caspase-9 significantly（P〈0. 01）,and improve the ratio of Bcl-2 to Bax,but with no obvious expression of P53. Conclusion： EGCG and PC-B2 can protect the human normal liver cells from the damage induced by AFB1 reducing L-02 cell DNA damage and inhibiting the apoptosis,and the mechanism may be correlated with the down-regulation of Caspase-3 and Caspase-9 expressions and the increase in Bcl-2 / Bax.

关 键 词：表没食子儿茶素没食子酸酯 原花青素B2 对黄曲霉素B1 DNA损伤 细胞凋亡 

分 类 号：R285.5[医药卫生—中药学]