茶叶对长寿相关基因CETP表达的影响

目的研究茶叶对人体正常皮肤成纤维细胞(GM细胞)中长寿相关基因胆固醇酯转运蛋白(CETP)编码基因表达的影响。方法采用逆转录PCR法和免疫印迹法分别检测GM细胞中CETP mRNA与蛋白的表达水平。结果高浓度(>2.5μg/μl)普洱茶叶水提取物能抑制GM细胞的生长且下调CETP mRNA表达,低浓度普洱茶叶水提取物(<2.5μg/μl)和绿茶中茶多酚(10μmol/L)能提高CETP mRNA与蛋白的表达,且呈现剂量和时间依赖性。结论 CETP基因可能是茶叶作用的靶点之一。

Effects of puer tea aqueous extracts and green tea polyphenols on the expression of longevity related gene CETP

Objective To study the effect of tea on the expression of longevity related gene CETP(cholesteryl ester transfer protein) in normal skin fibroblast GM0639(GM) cells in vitro.Methods Cell counting was used to evaluate cell growth;the expressions of CETP protein and mRNA were determined by Western blot and RT-PCR assay,respectively.Results Cell growth was suppressed after exposing GM cells to high concentration(>2.5 μg/μl) puer tea aqueous extracts,while the expression of CETP were increased at both protein and mRNA levels in dose-dependent manner with the treatment of low concentrations(<2.5 μg/μl).In order to further clear the potential impact of the tea effective components on CETP expression,four major green tea polyphenols,EGCG,EGC,ECG and EC,were added to the cultures of GM cells.EGCG and EGC(10 μmol/L) significantly up-regulated the CETP protein expression,however,EC and ECG exerted had no significant effects at equal concentrations.Moreover,EGCG mediated CETP up-regulation was in a time-dependent fashion.Conclusions Tea and its polyphenols are capable of up-regulating the expression of CETP gene,which might be helpful in giving a mechanistic explanation for tea consumption as health and longevity drink,and provide a direction in the study of CETP-longevity relationship.