Abstract: Liang Bihua, Liu Qing, Jiang Na, Zhang Qianwen, Zhang Erting, Deng Huiyan, Li Huaping, Li Runxiang, Li Zhenjie, Zhu Huilan Guangzhou Institute of Dermatology, Guangzhou 510095, China Corresponding author: Zhu Huilan, Email: zhlhuilan@126.com 【Abstract】 Objective To evaluate effects of tea polyphenols on the mRNA and nucleoprotein of Nrf2/Bach1 in human skin fibroblasts （HSFs）. Methods Some HSFs were incubated with tea polyphenols at different concentrations of 0, 2.5, 5, 10, 20 and 40 mg/L for 24 hours. Methyl thiazolyl tetrazolium （MTT） assay was conducted to evaluate the proliferative activity of HSFs to screen the optimal concentration of tea polyphenols. Then, some other HSFs were treated with tea polyphenols at this optimal concentration for 24 hours. Real?time quantitative PCR （RT?qPCR） was performed to determine mRNA of Nrf2 and Bach1, Western blot analysis to measure nuclear of Nrf2 and Bach1 proteins, and immunofluorescence assay to determine the distribution of Nrf2 and Bach1 protein in the cell nucleus. Results MTT assay showed that 5 mg/L tea polyphenols had no obvious effects on the proliferation of HSFs, so 5 mg/L was chosen as the optimal concentration of tea polyphenols for subsequent experiments. HSFs cultured without tea polyphenols served as control group. After the treatment, the 5?mg/L tea polyphenol group showed significantly decreased mRNA and nuclear protein of Bach1 （mRNA: 0.629 ± 0.077 vs. 0.940 ± 0.033, t = 6.397, P < 0.05; protein: 1.424 ± 0.171 vs. 16.966 ± 1.702, t = 15.730, P < 0.05）, but significantly increased mRNA and nuclear protein of Nrf2 （mRNA: 1.467 ± 0.076 vs. 0.977 ± 0.091, t = 7.133, P < 0.05; protein: 6.929 ± 0.121 vs. 3.537 ± 0.126, t = 33.636, P < 0.05） compared with the control group. Immunofluorescence assay showed increased accumulation of Nrf2 protein, but decreased accumulation of Bach1 protein in the nucleus. Conclusion Tea polyphenols can promote the mRNA and nuclear protein as well as nuclear distribution of Nrf2 , but suppress the mRNA and nuclear protein as well as nuclear distribution of Bach1, finally exerting anti?oxidative effects.