Effects Of VBE-3, A Noval Lignanoid From The Acetoacetate Extract Of Vitex Negundo Seed On Induction Of Apoptosis And Inhibition Of Akt Protein Phosphorylation In Human Ovarian Cancer CoC1 Cell Line

Objective:To investigate the effects of VBE-3, a noval lignanoid from the acetoacetate extract of Vitex negundo seed on apoptosis and inhibition of Akt protein phosphorylation in human ovarian cancer CoC1 cell line.Methods:Human ovarian cancer (CoC1) cell line and Chinese hamster ovary CHO-K1 cell line were cultured in vitro. Flow cytometry (FCM) using PI staining was used to analyse the apoptosis rate of both cell lines treated with VBE-3. DNA agarose gel electrophoresis was used to test apotosis induced by VBE-3 in the two cell lines. Western blot was used to analyze expression of protein and phosphorylated protein level in CoC1 cells.Results:Flow cytometry(FCM) analysis after PI stainning indicated that VBE-3 significantly induced apoptosis in a concentration-dependent, the rate of apoptosis was 0.86%±0.09%,3.06%±0.44%,3.40%±0.79% and 0.32%±0.04%,0.93%±0.06%,3.27%±0.35%, respectively after treatment with 0.1,1.0, 10.0μmol/L of VBE-3 for 24h, in CoC1 cell line and in CHO-K1 cell line. The ladder band could be shown in DNA agarose gel electrophoresis after treatment with VBE-3 or LY294002 or both at 10.0μmol/L for 24h in CoC1 cell line and the ladder-shape band disappeared, in CHO-K1 cell line. Western blot analysis indicated that exposure to VBE-3 or LY294002 or both at 10.0μmol/L for 24h, the phosphorylated protein level of Akt in CoC1 cells was decreased by 92.10%±1.96%,87.43%±0.83%and 84.03%±1.50%, respectively in comparision with the control group. At same condition, the phosphorylated protein level of p38 and the activity fragment(17KDa) of caspase-3 were up-regulated by 106.86%±1.76%,111.73%±2.19%,117.23%±1.34% and 105.20%±1.93%,111.30%±1.85%,121.53±2.87, respectively in comparision with the control group.1. VBE-3 can significantly induce apoptosis of CoC1 cells.2. The induction of apoptosis of CoCl cells by VBE-3 may be mediated by inhibiting phosphorylation of Akt protein sequentially accompanied by increase of phosphorylated protein levels of p38 and increasing of expression of the activity fragment(17KDa) of caspase-3.