中文摘要：

目的 探讨表没食子儿茶素没食子酸酯（EGCG）对不同剂量中波紫外线（UVB）慢性辐射BALB／c小鼠皮肤的保护作用。方法 EGCG局部外用于小鼠背部皮肤后予不同强度UVB辐射，每日1次，连续1个月，RT-PCR法检测IFN-γ和IL-10mRNA的表达水平变化。结果 不同剂量UVB慢性辐射后小鼠皮肤中IFN-γ mRNA表达水平较对照组降低（P〈0．01），IL-10mRNA表达水平较对照组升高（P〈0．01），并与UVB辐射强度呈一定剂量依赖关系。EGCG处理后可影响UVB辐射诱导上述细胞因子表达（P〈0．01）。结论 UVB辐射下调IFN-1和上调IL-10转录水平，可能与UVB辐射诱导局部免疫抑制有关。

英文摘要：

Objective To investigate the （ - ）-epigallocatechin-3-gallate （ EGCG ） photoprotection in BALB/c mouse skin damaged by chronic irradiation of different doses of ultraviolet B （ UVB ）. Methods BLAB/c mice were pretreated with topical EGCG on the back, followed by daily irradiation with different dosages of UVB. One month later, skin samples were obtained and detected for IFN-γ and IL-10 mRNA expression by RT-PCR. Results Compared with the control group, IFN-γ mRNA expression in the skin of BALB/c mice was significantly decreased, while IL-10 mRNA expression was significantly increased after chronic UVB irradiation （ both P 〈 0.01 ）, both in a dose-dependent manner. Topical application of EGCG had a significant influence （ P 〈 0,01 ） on the mRNA expression of IFN-γ and IL-10 induced by UVB irra- diation. Conclusions UVB irradiation could down-regulate IFN-γ mRNA expression but up-regulate IL-10 mRNA expression in BALB/c mice skin. EGCG has a potential photo-protective effect on UVB in- duced local immunosuppression in BALB/c mouse skin.