摘要
目的观察绿茶提取物巾的主要活性成分没食子儿茶素没食子酸脂(EGCG)对经多次长、中波紫外线(UVA、UVB)照射后人皮肤成纤维细胞(HSF)光老化及突变情况的影响。方法分离并培养新生儿包皮 HSF,将其分为正常对照组、EGCG 干预组、UVA 组、UVA+EGCG 组、UVB 组、UVB+EGCG 组;UVB 照射剂量为30 mJ/cm^2,UVA 照射剂量为10 J/cm^2,每天照射 HSF 共持续2周。预实验选定 EGCG 浓度25μg/ml。采用组织化学染色法检测细胞中衰老相关β-半乳糖苷酶的表达量,观察细胞老化情况;采用克隆法检测次黄嘌呤磷酸核糖转移酶(HPRT)基因位点突变频率,观察紫外线照射的致突变力以及加入 EGCG 干预后的情况。结果 (1)正常对照组及 EGCG 组均只见少量的β-半乳糖苷酶阳性细胞。其他几组阳性细胞比率为 UVB 组:43%±4%;UVA 组:54%±4%;EGCG+UVB 组:64%±5%;EGCG+UVA 组:75%±5%,4组细胞间阳性比率差异有统计学意义(P<0.05)。(2)正常对照组与 EGCG 处理组的 HPRT 自发突变率很低。单纯 UVB 及 UVA 照射诱导的突变分别是自发突变的72倍及241倍,而 UVB+EGCG 组和 UVA+EGCG 组分别较单纯 UVB 组和UVA 组降低了52.78%和32.37%,差异有统计学意义(t=2.0742、2.7042,均 P<0.05)。结论UVA、UVB 多次照射后均可上调 HSF 老化概率,加入 EGCG 可进一步上调其老化概率。UVA、UVB 多次照射后均可增加 HSF 的 HPRT 基因位点突变频率,加入 EGCG 可显著减少 HPRT 基因位点突变频率。提示 EGCG 对 UVA、UVB 多次照射 HSF 后的保护干预作用可能与诱导突变细胞老化从而减少细胞突变频率有关。
Objective To investigate the effects of epigallocatethi-3-gallate （EGCG） on the cell aging and hypoxanthine-phosphoribosyl-transferase （HPRT） gene mutation frequency induced by long-term ultraviolet （UV） A and UVB irradiation in human skin fibroblasts （HSF）. Methods HSF were separated from infant foreskin, cultured, and divided into six groups： control, EGCG group （treated by 25 μg/ml EGCG）, UVA group （irradiated by 10 J/ cm^2 UVA for 2 weeks）, UVB group （irradiated by 30 mJ/cm^2 UVB for 2 weeks）, UVA ＋ EGCG group and UVB ＋ EGCG group. β-galactosidase （ β-GAL）, a biological marker associated with senescence, was detected by histochemical staining. The HPRT gene mutation frequency was detected by the HPRT mutagenesis assay. Results The HSFs of the control and EGCG groups only showed a few β-GAL positive cells, and the β-GAL positive cell ratios of the other 4 groups were higher and could be arranged from low to high according to the sequence： UVB group （43% ±4% ） 〈 UVA group （54% ±4%） 〈 EGCG ＋ UVB group （64% ±5%） 〈 EGCG ＋ UVA group （75% ±5%）. The mutation rates of the control and EGCG groups were very low. The mutation rates of the UVB and UVA groups were 72 and 241 times that of the control group. The mutation rate of the UVB ＋ EGCG and UVA ＋ EGCG groups were significantly lower than those of the UVB and UVA groups by 52.78% and 32.37%, respectively （t =2. 0742,2. 7042, both P 〈 0.05 ）. Conclusion The photo-protection of EGCG on HSFs from long-term UVA and UVB irradiation may be related to both the direct reduction of HPRT mutation frequency and the indirect induction of aging cells, thus decreasing the mutation frequency.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2007年第20期1398-1401,共4页
National Medical Journal of China
基金
路家自然科学基金(30371294)
