Effect and mechanism of HeLa cell apoptosis induced by crocin

OBJECTIVE:To investigate the growth inhibition and the apoptosis of HeLa cells induced by crocin,and explore the underlying molecular mechanism. METHODS:MTT essay was used to examine the suppressive effect of crocin on the proliferation of HeLa cells,at concentrations of 0,0.2,0.4 and 0.8 mmol/L. Other HeLa cells were cultured with normal medium or that mixed with colchicine (10 μg/L) or crocin (0.4 and 0.8 mmol/L) for 48 hours before they were harvested for examination by AnnexinⅤ and propidium iodide (PI) staining by the Annexin V-FITC Apoptosis Detection Kit. Western blot assay were used to determine the activation of Caspase-3 after 1.6 mmol/L crocin interacted with HeLa cells for 72 hours. RESULTS:MTT test analysis showed that in 0,0.2,0.4 and 0.8 mmol/L concentrations,the survival rates of HeLa cells were 1,0.964,0.796 and 0.586 respectively,and statistically significant differences existed among the different concentrations of crocin. Crocin significantly inhibited the growth of HeLa cells (P0.05). AnnexinⅤ and propidium iodide (PI) staining showed that the apoptosis rates of HeLa cells of the PBS group,10 μg/L colchicine positive control group,0.4 mmol/L and 0.8 mmol/L crocin treated group were 3.64%,15.99%,4.86%,9.28%,respectively,indicating crocin promoted the apoptosis in HeLa cells. Caspase-3 was activated in the apoptosis of HeLa cells. CONCLUSION:Crocin can significantly inhibit the growth of HeLa cells through pro-apoptotic action,probably via the activation of Caspase-3.