Preparation of nano-crystalline of oridonin and its effect on cell proliferation and apoptosis of colorectal cancer cells in vitro

Objective To prepare the nano-crystalline of oridonin and to investigate the effect on the proliferation and apoptosis of colorectal cancer cells. Methods The contents of oridonin nanosuspensions were prepared by high pressure homogenization. The nano-crystalline of oridonin was obtained after adding 5% mannitol,and then shaking and lyophilizing. The solubility was determined in vitro. Colorectal cancer cells( Lovo cells,SW480 cells,HCT-116 cells and HCT-8cells) were cultured in vitro and incubated with different concentrations of nano-crystalline of oridonin( 0,5,10,15 and25 μg / m L). Cell proliferation was detected by cytometry. The apoptosis and cell cycle of cultured cells in different concentrations of nano-crystalline of oridonin( 5,10 and 25 μg / m L) were detected. Results The nanosuspensions and nanocrystalline of oridonin was prepared successfully. There were significant differences in the proliferation inhibition rate among four kinds of colorectal cancer cells that were intervened by different concentrations of nano-crystalline of oridonin for 24 h and 72 h( all P 0. 05). The nano-crystalline of oridonin with concentration of 25 μg / m L had the strongest inhibitory effect on cell proliferation as compared with the others( all P 0. 05). The nano-crystalline of oridonin could block cell cycle of the Lovo cells and HCT-8 cells at G1 phase,and block the HCT-16 and SW480 cell cycle at S phase. Conclusion The vitro dissolution of nano-crystalline of oridonin is higher than oridonin. The nano-crystalline of oridonin can significantly inhibit the proliferation,induce the apoptosis and block the cell cycle of four kinds of colorectal cancer cells.