Effects of Triptolide on Proliferation and Apoptosis of Human Hepatocytes

Abstract:

Objective:To study the effects of triptolide on proliferation and apoptosis of human hepatocytes(L-02 cells), providing experimental basis for the clinical application of triptolide in treatment of liver diseases and the prevention of its liver toxicity. Method: Culture L-02 cells in vitro and treat the L-02 cells with 10, 30, 50 nmol·L^-1 triptolide respectively for 48 h. Detect the cellular growth and proliferation using trypan blue staining and Brdu incorporation, detect cell cycle distribution using PI staining,detect the percentage of cellular apoptosis using AV/PI double staining,detect the expression levels of p21 and p53 using western blot analysis. Result: Compared with the control, after treated with 10, 30, 50 nmol·L^-1 triptolide, the cell number was reduced from (2.72±1.14)×10⁵ cells/mL to (1.95±0.38)×10⁵,(1.44±0.44)×10⁵,(6.97±0.47)×10⁴ cells/mL respectively;the percentage of Brdu positive cells was reduced from (7.67±0.51)% to (5.67±0.29)%, (4.05±0.14)%, (2.51±0.15)% respectively;the percentage of cells arrested in G₁ stage was increased from 65.39% to 68.47%, 71.19%,83.98% respectively;the percentage of apoptotic cells was increased from (20.54±1.44)% to (28.02±0.93)%,(36.79±0.49)%,(43.35±1.12)% respectively; the expression level of p21 and p53 protein were both up-regulated, and showed a dose-effect relationship. Conclusion: Triptolide could inhibit L-02 cells proliferation through up-regulation of p21 expression thus arresting cells in G₁ stage, and induce cellular apoptosis through up-regulation of p53 expression in L-02 cells.