LPS induce DNA damage (I), and comet assay’s parameters were analyzed by CASP software (II). (I) A. control group; B. 20 μg/ml group; C. 40 μg/ml group; D. 50 μg/ml group; E. 100 μg/ml group; F. 200 μg/ml group; G. 400 μg/ml group; and H. H2O2-positive group. The DNA parameters were analyzed by CASP software, and values were shown in part II. (II) SGN were treated with different concentrations of LPS for 48 h or H2O2 (30 μM) for 15 min. The levels of DNA damage were expressed as the tail DNA (%) (A), tail moment (B), and tail length (μm) (C). The H2O2 group was defined as the positive group. *P < 0.05, **P < 0.01 compared to the control group. Two hundred nuclei were analyzed for each group of experiment. LPS, lipopolysaccharide.