Activation Of AMP-activated Protein Kinase Is Involved In Oridonin-induced Colon Cancer Cell Apoptosis

Background: To investigate the apoptosis of colon cancer cell HT-29induced byoridonin and its mechanism.Methods: After administration of1-50μmol／L oridonin，the ELISA method wasused to investigate the apoptosis rate of oridonin on HT-29cells. The expressions ofC-caspase-3and AMPKa proteins were determined by Western blot．The caspase-3activitywas investigated by Spectrophotometric assay.Results: HT-29cells apoptosis was induced by different concentration of oridonin.The apoptosis rate was increased together with the increased concentration oforidonin(p<0.05). And also the elevated expression of Caspase-3(p<0.05). Based ondifferent reaction time, the expression of p-AMPKa protein band gradually became deepand thick by Western blot. Meanwhile, oridonin-induced activation of AMPK wassignificantly decreased on the HT-29cells transfected by AMPK siRNA（26.33±5.03）％compared with the activation of AMPK transfected by cramble siRNA（84.4±9.7）％, thedifference was statistically significant for p<0.05. And oridonin-induced activation of p53was significantly decreased on the HT-29cells transfected by AMPK siRNA comparedwith the activation of AMPK transfected by cramble siRNA.Conclusions: Apoptosis of HT-29cells induced by oridonin may be associated withthe activation of AMPK．And the expressions of the activation of Caspase-3and p53maybe involved in its mechanism.