Effect of Gypsophila elegans isoorientin on proliferation and apoptosis of human HepG2 cells / 中国药理学与毒理学杂志

ABSTRACT

OBJECTIVE To investigate the effect and underlying mechanism of Gypsophila elegans isoorientin on the proliferation and apoptosis of human HepG2 cells. METHODS HepG2 cells were treated with isoorientin 5,10,20,40,80 and 160μmol?L-1 for 24,48 and 72 h,respectively. Cell survival was analyzed by MTT assay. HepG2 cells were treated with isoorientin 5,10 and 20μmol?L-1 for 48 h before the lactate dehydrogenase(LDH)level was detected. After treatment with isoorientin for 24 h, the variation of reactive oxygen species (ROS) was monitored by a fluorescence probe H2DCF-DA. HepG2 apoptosis and mitochondria membrane potential(MMP)were evaluated by flow cytometry. The activi?ties of caspase 3,8 and 9 were determined by colorimetry. The mRNA expression of Bcl-2 and Bax was determined by RT-PCR,and the protein expression of Bcl-2, Bax and cytochrome c was detected by Western blotting. RESULTS Isoorientin(5-160μmol?L-1)inhibited HepG2 cell survial in a concen?tration-dependent manner,the 50%inhibitory concentration(IC50)was 62.7±9.1,47.2±11.4 and(18.2± 7.5)μmol?L-1 after treatment with isoorientin for 24,48 and 72 h,respectively. Compared with the cell control group,treatment with isoorientin 5,10 and 20μmol?L-1 significantly increased the LDH level and cell apoptosis rate(P<0.05). Moreover,isoorientin 10 and 20μmol?L-1 notably increased the production of ROS,decreased the MMP(P<0.05),and increased the activities of caspase 3 and 9. RT-PCR analysis and Western blotting showed that isoorientin significantly decreased the mRNA and protein expressions of Bcl-2,decreased the mRNA and protein expressions of Bax(P<0.05),and inhibited the protein expression of cytochrome c(P<0.05). CONCLUSION Isoorientin inhibits HepG2 cell prolif?eration,but promotes cell apoptosis,which is closely related to the regulation of the mitochondrial apoptosis pathway.