| Benzene-sulfonyl paeoniflorin(CP-25)is a new esterification derivative of Paeoniflorin(Pae).Our previous studies showed that CP-25 has a significant inhibitory effect on inflammation,has a good therapeutic effect on rat AA.The current study group confirmed that the pharmacological activity and bioavailability of CP-25 was higher than that of Pae,and the in vivo rat single-pass perfusion model indicates that CP-25 was superior to Pae in intestinal absorption.The pharmacokinetics of CP-25 in rats was much better than that of Pae and the oral bioavailability was 2-3 times higher than that of Pae(10.6%).However,the absorption characteristics of CP-25 in Caco-2 cells remains unclear.Caco-2 cell model is a well-established in vitro model of human intestinal epithelial cells,which expression lever of the hydrolase,P-glycoprotein(P-gp),and other membrane transporter levels are comparable to human intestinal epithelial cells.Thus it was often used to study the absorption and transport mechanisms of the tested drugs in human intestinal cells.Therefore,the purpose of this study was to investigate the mechanism of absorption and transport of CP-25 in the Caco-2 cell model,providing experimental and theoretical basis for the study of CP-25 in the later period.Objective Investigated the mechanism of CP-25 absorption and transport in the Caco-2 cell model.Methods 1.A high-performance liquid chromatography(HPLC)methodology was established to determine the content of CP-25 and Pae in Caco-2 cell model.HPLC method was used to detect the concentration of CP-25 in the apical side(AP side)and basolateral side(BL side)and calculate their Papp and PDR.2.The effects of P-glycoprotein(P-gp)inhibitor GF120918,Multidrug resistance-associate protein 2(MRP2)inhibitor MK571 and Breast cancer resistance protein(BCRP)inhibitor KO143 on CP-25 transport in Caco-2 cells were investigated;the effects of different concentration,temperature and time on CP-25 transport in Caco-2 cells were investigated.3.The effects of CP-25 on the expression of P-gp,MRP2 and BCRP were examined by Western blot;the effects of CP-25 on the activity of P-gp were examined by flow cytometry.Results 1.The Papp values of CP-25(5,10,20μg / m L)from AP side to BL side ranged from about 0.9 to 2.0 × 10-6cm / s and the Papp value of Pae(5,10 and 20μg / m L)from the AP side to the BL side is about(0.3~0.6)× 10-6cm / s,suggesting that absorbability of CP-25 was superior to Pae in Caco-2 cells.2.Absorption of CP-25 and Pae were concentration-dependent at the concentration of 2,5,10,20 μg / m L and all groups of PDR were less than 1.5,indicating that absorption mechanism of CP-25 and Pae were passive transport;the Papp value of CP-25 and Pae significantly decreased at 4 ℃,suggesting that active transport may also was the absorption mechanism of CP-25 and Pae.3.During 0 ~180 min,the Papp value of CP-25(10 μg/m L)were significantly higher at 60 min,Pae have no obvious statistical significance during the time,the Papp value of CP-25 was significantly higher when compared with Pae at 180 min,suggesting that the absorption of CP-25 was much better than Pae.4.GF120918 and MK571 could significantly decrease the Papp value of CP-25 and Pae transport from the BL side to the AP side,KO143 has no obvious effect on the bidirectional transport of CP-25 and Pae.5.CP-25 could significantly down-regulate the expression of P-gp and MRP2,enhance intracellular accumulation of RHO 123.Conclusions 1.Passive transport was the main mechanism of CP-25 absorption,active transport may also be involved.2.CP-25 is P-gp and MRP2 substrates,but not BCRP substrates.3.CP-25 could down-regulate the expression of P-gp and MRP2,inhibit the function of P-gp. |
PDF Full Text Request