Wang Yinglei, Zhao Jing, Zhao Yong, Li Chunying, Yi Yan, Liang Aihua, Odd Georg Nilsen
Capital Medical University School of Traditional Chinese Medicine, Beijing 100069, China.
Zhongguo Zhong Yao Za Zhi. 2012 Apr;37(7):991-6.
To investigate the effect of Shao Yao-Gan Cao-Tang on function and expression of P-glycoprotein (P-gp) in Caco-2 cells.
3H-digoxin (Dig), a substrate of P-glycoprotein, was used as a probe to measure the P-gp-mediated drug efflux transport, which indicated the function of P-gp in Caco-2 cells, while Verapamil (Ver) was used as a positive P-gp inhibitor. P-gp expression in Caco-2 cells was tested by immunohistochemistry staining. Inhibition effect of SGT on P-gp-mediated drug efflux transport and P-gp expression were investigated.
Dig was shown a positive absorption mode in Caco-2 cell monolayer, characterized as the ratio of apparent permeabilities (Papp) from basolateral side to apical side Papp (BL-->AP) and from apical side to basolateral side Papp (AP-->BL) of Dig was 27.07. Addition of Ver into Dig transport media significantly inhibited P-gp activity which was indicated by increasing the Papp (AP-->BL) of Dig by 3.82 times, whereas Ver had no significant effect on Papp (BL-->AP). SGT (at the concentrations of 1/25 IC5, 1/5 IC5, IC,) could promote Papp (AP-->BL) of Dig by 159.83%, 217.95% ,160.26%. Papp (AP-->BL) of Dig was mildly increased by 59.16%, 50.73% by SGT at 1/25 IC5, 1/5 IC, respectively. Immunohistochemistry staining showed that SGT inhibited the expression of P-gp of Caco-2 cells.
SGT showed the potential inhibition to the function and expression of P-gp, leading to the increase absorption of P-gp's substrates.
