Experimental Study of Ultraviolet Irradiation on Skin Fibroblasts / 中华皮肤科杂志

ABSTRACT

Objective To investigate the effects of ultraviolet irradiation on the morphology, cell proli-feration, mutation frequency and level of expression of ATP mRNA in human fibroblasts. Methods The infant foreskin fibroblasts were cultured and irradiated with different doses of ultraviolet A or B (UVA or UVB). Light microscopy was used for observing the morphologic change and cell counting of cell proliferation, HPRT-mutagenesis assay for the mutation detection, and RT-PCR for the expression of ATP mRNA. Results Compared with the control group, the irradiated cultured fibroblasts were damaged, cell growth was retarded (MTT assay showed 2.4 fold increase in the control group but only 0.2 fold in the UVB group 72 h after irradiation). Mutation frequency in 106 colony forming cells was increased from 20.4 ? 6.7 at 20 mJ/cm2 to 97.7 ? 7.1 under 60 mJ/cm2 of UVB irradiation. The expression level of ATP mRNA was down-regulated after UV irradiation. There was an increase of mutation frequency which was UVB dose-dependenct, and decrease of ATP mRNA expression which was dose- and time-dependent. Conclusions After UV irradiation of the cultured fibroblasts, the cell damage and growth inhibition are induced, and the mutation frequency is increased in a UVB dose-depen-dent maaner. The expression of ATP mRNA shows down-regulation in both dose- and time-dependent manner.