Objective To observe the inhibitory effect of two combinations of active fractions of
Qixuebingzhi Formula, the active
fractions D (mainly paeoniflorin) and E (mainly total flavones) blended according to a ratio based on the original formula and D and E blended according to an optimized ratio, on the smooth muscle cell (VSMC) proliferation caused by ox-LDL-induced vascular endothelial cell (VEC) injury-conditioned medium. Methods VSMC was cultured respectively in the normal VSMC culture fluid, ox-LDL-induced VEC injury-conditioned medium, simvastatin plus ox-LDL-induced VEC injury-conditioned medium, D and E blended according to the original formula plus ox-LDL-induced VEC injury-conditioned medium, and D and E blended according to an optimized ratio. MTT staining method was used to assess the growth state of VSMC and a flow cytometry method was used to detect the cell cycle of VSMC. Results After being cultured in VEC injury-conditioned medium, the activity of VSMC proliferation was markedly increased (P<0.01) and the number of S-phase cells was raised, as compared with the results from the normal control group; and the activity of VSMC proliferation was found to be markedly lower (P<0.01) and the number of S-phase cells was found to be reduced in the group of D and E blended according to the original formula (1 mg/L) and the group of D and E blended according to an optimized ratio (1 mg/L), the effects of which were like the those of simvastatin. Conclusion Both combinations of the active fractions of
Qixuebingzhi Formula can effectively inhibit VSMC proliferation induced by VEC injury-conditioned medium, to which the mechanism of Qixuebingzhi Formula for preventing and treating
atherosclerosis is closely related.