Abstract: Objective To study the effects of extract 5F from Pteris semipinnata L.on the apoptosis of skin fibroblasts in patients with systemic scleroderma (SSc) and the possible mechanism of its inhibition on the proliferation of skin fibroblasts.Methods The cultured SSc skin fibroblasts were used as an experimental model, and the apoptosis of SSc skin fibroblasts before and afte r the extract 5F stimulation was detected by TUNEL assay and fluorescent microsc opy.Results The apoptosis of SSc skin fibroblasts was induced by the extract 5F, and the apoptosis was enhanced along with the increase of the concentration and incubation time of this compound within definite limits.Conclusions These results indicate that the extract 5F can induce the apoptosis of SSc skin fibro blasts, and significantly inhibit the proliferation and collagen synthesis in these cells.

Key words: Scleroderma,systemic, Fibroblast, Apoptosis, Pteris semipinnata