Protective Effect And Mechanism Of Saussurea Medusa Maxim Water Extracts Against Apoptosis Of UVB Irradiated HaCaT Cells

Objective: To study whether Saussurea medusa Maxim. water extracts could reduce apoptosis of ultraviolet B(UVB) on HaCaT cells and explore its possible mechanism. Method: The cells were divide into control group, UVB radiation group(30mJ/cm2) and Saussurea medusa Maxim. water extracts group(30mJ/cm2UVB+10mg/mL Saussurea medusa Maxim. water extracts). The morphology and dea th of cells were observed by trypan blue staining. Cell proliferation was dete cted by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxymethoxyphenyl)-2-(4-su lfophenyl)-2H-tetrazolium,inner salt(MTS).Superoxide dismutase(SOD) activity,catalase(CAT) activity, malondialdehyde(MDA) content and glutathione(G SH) content were assayed by Superoxide dismutase(SOD) activity test kit, gl utathione(GSH) content test kit, malondialdehyde(MDA) content test kit resp ectively. The apoptosis rate of the cells, the changes of mitochondrial membr ane potential and Ca2+ in cells were determined by flow cytometry. B cell ly mphoma factor 2(Bcl-2) and bcl-2 associated X protein(Bax) were determin ed by Elisa method. Western blotting and immunofluorescense were used to d etect the expressions of Bcl-2, Bax and cysteine proteinase 3(caspase-3). Results: Saussurea medusa Maxim. water extracts could significantly restore morphology of the cells, reduce the number of blue-stained cells and improve the death debris and off-chip of the cells. Promote the proliferation of the cells. SOD activity, CAT activity and GSH content was decreased, MDA content was increased(P<0.05). Saussurea medusa Maxim. water extracts could reduce cell apoptosis and Ca2+ in cells, increase mitochondrial membrane potential radiated by UVB. Increase the expression of Bcl-2, reduce the expressions of Bax(P<0.05)and Caspase-3 by Elisa method. And Saussurea medusa Maxim.water extracts can increase the expression of Bcl-2, decresas the expressions of Bax(P<0.05)and Caspase-3 by Western blotting and immunofluorescense methods. Conclusion:Saussurea medusa Maxim. water extracts can reduce apoptosis of HaCaT cells to reduce oxidative damage of Ha CaT cells after UVB radiation.