RESUMO
Objective To observe the effect of hydrogen on ultraviolet B (UVB)-induced oxidative damage to skin fibroblasts.Methods Primary human skin fibroblasts from foreskin tissues were divided into five groups:normal control group receiving no treatment,hydrogen control group treated with hydrogen-rich saline,UVB group receiving irradiation only,post-treatment group irradiated with UVB followed by hydrogen-rich saline treatment,and pre-treatment group treated with hydrogen-rich saline followed by UVB irradiation.The dose of UVB was 30,60 and 90 mJ/cm2 in the cell proliferation assay and 90 mJ/cm2 in the other experiments.Methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferative activity of fibroblasts,a chemiluminescence method to estimate the activity of superoxide dismutase (SOD) and catalase as well as to determine the level of malondialdehyde in the culture supernatant of fibroblasts,enzyme linked immunosorbent assay (ELISA) to determine the supernatant level of 8-isoprostane-prostaglandin F2α (8-iso-PGF2α),Western blot to detect the expression of heme oxygenase-1 (HO-1) in fibroblasts.One-factor analysis of variance was conducted to assess differences in these parameters among these groups.Results UVB irradiation decreased the proliferative activity (absorbence value at 490 nm) of fibroblasts in a dose-dependent manner.Both the pre-treatment group and post-treatment group showed a statistical increase in proliferative activity of cells compared with the corresponding UVB control groups (all P ＜ 0.05).The activity of SOD and catalase as well as the protein expression of HO-1 were significantly higher (all P ＜ 0.05),whereas the supernatant levels of malondialdehyde and 8-iso-PGF2α were statistically lower (both P ＜ 0.05) in the pre-treatment group and post-treatment group than in the UVB control group.Conclusion Hydrogen may mitigate UVB-induced oxidative damage to skin fibroblasts.