Inhibitory Effect of Ursolic Acid on Ultraviolet B Radiation-Induced Oxidative Stress and Proinflammatory Response-Mediated Senescence in Human Skin Dermal Fibroblasts

Figure 6

Fluorescent microscopy images of DNA damage in HDFs treated with UA, UVB radiation, and UA+UVB radiation by using comet assay; (a, b) Round nuclei with red staining showing the DNA was not damaged in HDFs treated with UA 20 μM; (c) lack of round nuclei with comet tail length indicated increased DNA damage in HDFs by UVB 40 mJ/cm² irradiation; (d–f) the DNA damage was gradually decreased in HDFs by pretreatment of UA (10, 20, and 40 μM) with UVB 40 mJ/cm² irradiation. Graphs are showing the % head DNA, tail length, tail moment, and Olive tail moment levels. All images were captured at 40x magnification; the bars represent of six separate experiments ( per group). Statistical analysis was performed by one-way ANOVA followed by DMRT at , , and compared to the nonirradiated control. values not sharing a common marking (, , and ) differ significantly (DMRT).