Abstract: Objective To study the protective effect of Sanhuangyinchi Fang drug serum (SF) against hydrogen
peroxide-mediated DNA oxidative damage in LO2 cells. Methods The LO2 cells were randomly divided into the control
group , H2O2 group, SF groups (5%, 10%, and 15%) and vitE group. The morphological features of the treated LO2 cells were
observed under inverted microscope. The viability of the treated cells was assessed with CCK-8 method, and the activity of
SOD, CAT and GSH-PX were detected biochemically. Reactive oxygen species (ROS) levels, the content of 8-OHdG, and DNA
damage of the cells were evaluated by flow cytometry, ELISA, and Comet assay, respectively. Results Compared with H2O2
group, the cells in SF groups (10% and 15%) and vitE group showed higher cell survival rate (P<0.05) and higher SOD, CAT,
GSH-PX (P<0.05) and ROS scavenging activities (P<0.01) with markedly decreases the content of 8-OHdG (P<0.01) and reduced
tailing ratio, tail length, tail moment and Olive tail moment (P<0.05). Conclusion SF drug serum, especially at the
concentration of 15%, can protect LO2 cells from H2O2-mediated DNAoxidative damage.