Abstract:

Abstract:Objective
To observe the effect of 20(s)-protopanaxadiol (PPD) on the cell cycle of Siha cells in vitro and to detect the transcription and expressions of p53,p21 and cyclin-E，and to clarify the mechanism of its inhibitory effect on proliferation of Siha cells.Methods The Siha cells cultivated in vitro were treated with alcohol (negative control group) and 20  μg•L^-1 PPD (PPD group), respectively. The cell cycle was detected by FCM 48 h after treatment.The mRNA  and protein expressions of p53,p21 and cyclin-E in Siha cells were analyzed by Real time PCR and Western blotting.Results Compared with negative control group,after treated with 20  μg?L-1 PPD for 48 h,the ratio of Siha cells at G ^₀/G1 phase was increased (P<0.01),the blockage of G1 phase was obviously enhanced;the transcription and protein expressions of p53 and p21 were up-regulated (P<0.01);while the transcription and expression  of cyclin-E were significantly decreased (P<0.01).Conclusion PPD may inhibit the proliferation of Siha cells,and its mechanism may be related to up-regulating the expressions of p53 and p21 and down-regulating  the expression of cyclin-E.

Key words: 20(s)-protopanaxadiol, Siha cells, p53, p21, cyclin-E