Protective Effect Of Ginsenosides On Skin Cells From Ultraviolet Injury

Objective To investigate the protective effects of Ginsenoside Rg1 on fibroblast and neuron-differentiated PC12 cells which are considered as skin neurons in this research.Moreover,to detect the functional relation between skin fibroblasts and differentiated PC12 cells,which may support the idea that protecting skin nerve from UV is as important as protection of other skin cells,like fibroblasts,keratinocytes.Methods In experiment one,firstly,the fibroblasts were exposed to UVB (radiation dosage:60mJ / cm2).The fibroblasts were randomly divided into five groups including 1 control group and 4 UVB radiation groups(UVB radiation group.UVB+50μmol/L Rg1,UVB+25μmol/L Rgl,UVB+10μmol/L Rg1).Cell survival rate was detected by MTT assay.Sencondly,the fibroblasts were exposed to UVB(radiation dosage:60mJ / cm~2).The fibroblasts were randomly divided into four groups including 1 control group and 3 UVB radiation groups(UVB radiation group,UVB+Rg1treatment before radiation,UVB+Rg1treatment after radiation).The content of MDA and activities of SOD in the supernatant were detected by biochemical methods.In In experiment two,firstly,normal PC12cells were induced by NGF(50ng/L);secondly,neuron-differentiated PC12 were exposed to UVB(radiation dosage:100mJ/cm~2).The cells were randomly divided into five groups including 1 control group and 4 UVB radiation groups(UVB radiation group.UVB+50μmol/L Rg1,UVB+25μmol/L Rg1, UVB+10μmol/L Rg1).Cell survival rate was detected by MTT assay.Thirdly,the PC12 cells were exposed to UVB(radiation dosage:100mJ / cm~2).The fibroblasts were randomly divided into four groups including 1 control group and 3 UVB radiation groups(UVB radiation group,UVB+Rg1treatment before radiation,UVB+Rg1treatment after radiation).The content of MDA and activities of SOD in the supernatant were detected by biochemical methods.In experiment three,supernatant was abstracted from UV-damaged PC12 and was added to UVB-damaged fibroblasts.The survival rate of Fb was detected by MTTassay. The expression of c-fos and SP on PC12 after radiation were tested by IHC.Result In experent one,UVB(radiation dosage:60mJ/ cm~2) significantly decreased the proliferation activities of fibroblasts and decreased intracellular SOD and significantly increase MDA content.Rg1 can signifcantly improve the activities of cellular proliferation and intracellular SOD and significantly decrease the contents of intracellular MDA(P＜0.01,respectively).In the experiment two,UVB(radiation dosage:100mJ / cm~2) decreased the the proliferation activities of PC12 and intracellular SOD,at same time,significantly increase MDA content.Rg1 can significantly improvethe activities of cellular proliferation and intracellular SOD and significantly decrease the contents of intracellular MDA(P＜0.01,respectively).In experiment three,the supernatant abstracted from UV-damaged PC12 increased proliferation of damaged fibroblasts.After radiation,some of PC12 positively expressed c-fos and SP.Conclusion The Rg1 has protective effects on fibroblasts and skin neuron model(neuron-differentiated PC12 cells)radiated by UVB.The mechanism of the protective effect may be associated with its antioxidative function and its ability of improving activity of SOD.Skin nerve and fibroblasts may have functional relation.Skin nerve may secrete certain factors performing stimulating effects on fibroblasts,which supports the suggestion that protection of skin nerve is necessary.