Protective Effect Of Polysaccharides From Boschniakia Rossica On Tbhp-inducded Apoptosis Of Liver Cells

Objective:To study the protective effect and the molecular mechanism of polysaccharides from Boschniakia rossica(BRPS)on tert-butyl hydroperoxide(TBHP)-induced apoptosis of HepG2 cells.Methods:The cellular apoptotic model was established by treating HepG2 cells with TBHP.Cell toxicity was tested by MTT method,the apoptotic and morphological changes were detected by Hoechst fluorescent staining.The mitochondrial membrane potentials were observed by JC-1 fluorescent staining.The protein expressions of cleaved caspase 3,procaspase 8,cleaved caspase 9,Bax,Bcl-2,JNK,p-JNK,ERK,p-ERK,p38 and p-p38 were determined with western blotting method.Result:The results revealed that TBHP decreased the cell viabilities,promoted cell apoptosis,decreased the mitochondrial membrane potentials,up-regulated the protein expressions of cleaved caspase 3,cleaved caspase 9 and Bax,and down-regulated the protein expressions of procaspase 8 and Bcl-2.In addition,NAC and BRPS elevated the mitochondrial membrane potentials,down-regulated the protein expressions of cleaved caspase 3 and cleaved caspase 9,and elevated the ratio of Bax/Bcl-2.Furthermore,TBHP up-regulated the protein expressions of p-JNK,p-ERK and p-p38.BRPS down-regulated the protein expressions of p-JNK,p-ERK and p-p38.Conclusion:BRPS has the protective effect on apoptosis of HepG2 cells induced by TBHP,which may be related to the inhibition of JNK,ERK and p38.