Effect of brazilin on proliferation and apoptosis of bladder carcinoma T24 cell line

Abstract

Objective To observe the effects of brazilin on proliferation and apoptosis in T24 cells.Methods Trypan blue exclusion test was performed to detect the inhibition of brazilin on the growth of T24 cell lines in vitro cultured within different time.After exposure to different concentrations of brazilin,homogeneous bioluminescence assay was used to detect the inhibitory action of brazilin,Caspase-3 and Caspase-9 activity on T24 cells.Cellular apoptosis was measured by flow cytometry (FCM) and observed by laser scanning confocal microscope.Results Brazilin could significantly inhibit the proliferation of T24 cells after 8 hours,the inhibitory rates of the brazilin at concentration of 25,50,100,200 μg/ml against T24 cells respectively were 43.19 ％,60.73 ％,86.38 ％ and 93.89 ％ (P ＜ 0.05).After exposured to 50 μg/ml of brazilin,the inhibition ration to T24 cells increased with time prolonging (52.72 ％ in 4 h,60.73 ％ in 8 h,91.77 ％ in 24 h,96.41％ in 48 h) (P ＜ 0.05).The activity of Caspase-3 and Caspase-9 increased slightly when brazilin was at 25 μg/ml,but there was no statistical differences compared with that in the control group (P ＞ 0.05).When cells were treated with an increase of the concentration of brazilin from range of 7.5-60 μg/ml for 16 hours,the apoptosis ratio in turn showed a upward trend of 0.15 ％,1.35 ％,2.91％,34.76 ％.It could be seen by laser scanning confocal microscope that the apoptosis occurred in the cells.Conclusion Brazilin can effectively inhibit the proliferation of T24 cells and induce apoptosis in a dose and time dependent manner. Key words: Urinary bladder neoplasms; Brazilin; T24 cells; Inhibition; Proliferation; Apoptosis