[Transport mechanism of isorhapontigenin based on human intestinal Caco-2 cells]

Isorhapontigenin (ISO) is suggested to have many different kinds of pharmacology activities, such as anti-inflammatory effect, anti-oxidation effect and anti-cancer effect. This paper mainly discussed the transport mechanism of ISO in Caco-2 cell models. The concentration of ISO was determined by UPLC method with PDA detector at 310 nm, and then the apparent permeability coefficient Papp was calculated. The cytotoxic of different concentrations of ISO was investigated on Caco-2 cells to determine the concentration of drug administration. The effects of ISO concentration, time, temperature and transporter inhibitors on the transport of ISO were investigated. The test results showed that, ISO didn't have significant cytotoxicity at 10-60 μmol•L ⁻¹ in 14 hours. The transportation of ISO on Caco-2 cells was related to the concentration to a certain extent. Papp of ISO was higher than 10×10-6 cm•s ⁻¹ and ISO was absorbed easily by Caco-2 cells. The transport volume of ISO at BL side reached maximum at 3 h and was slightly decreased at 6 h. Papp (AP-BL) and Papp(BL-AP) at 4 ℃ were lower than those at 37 ℃. Papp (AP-BL) of ISO was significantly increased after adding P-gp inhibitor verapamil and Papp (BL-AP) of ISO was significantly decreased after adding MRP-2 inhibitor (probenecid or MK-571). The results suggested that transport mode of ISO was mainly passive diffusion in Caco-2 cell models, and P-gp and MRP may be involved in the transport of ISO.