The Relationgship Intestinal Absorption Of Mangiferin With The P-gp And MRP2

Objective:1. To investigate the influence of P-glycoprotein (P-gp) and multidrug resistance-associated protein 2 (MRP2) on the intestinal absorption of mangiferin by pharmacokinetic study.2. To study the correlation between P-gp and MRP2 by the established in-situ single pass perfusion models in rats.3. To investigate the influence of P-gp inhibitor on the absorption of mangiferin by the established MDCK-MDR1 cells monolayer model.Method:1. A rapid, specific and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated for the determination of mangiferin in plasma samples. A rapid, specific and sensitive ultra performance liquid chromatography (UPLC) method and multimode reader were developed and validated for the determination of mangiferin and phenolred in perfusion fluid.2. Pharmacokinetic study of mangiferin in rats:SD rats were divided randomly into 6 groups and administered orally by mangiferin monomer, mangiferin with verapamil, mangiferin with cyclosporine A and mangiferin with indomethacin. Blood samples were withdrawn at different time. The blood samples were determined by the established LC-MS/MS. DAS2.0 software was applied to calculate the pharmacokinetic parameters while SPSS software was used for statistical analysis.3. In-situ intestinal absorption study of mangiferin in rats:In-situ single pass perfusion models was established and applied to determine the concentration of mangiferin in perfusion and phenol red in liquid. The absorption rate constant (Ka) and the apparent absorption coefficient (Peff) of mangiferin in various intestinal segments were calculated by the determined mangiferin concentration correction to investigate the relation of the absorption of mangiferin with P-gp and MRP2.4. Study on the effect of P-gp transport on mangiferin:The MDCK-MDR1 cells monolayer model was established and applied to determine and calculate the values of Papp in the direction of AP to BL and BL to AP in the same transport condi tion and the same dose of mangiferin to study the effect of P-gp inhibitor on the absorption of mangiferin.Result:1. The influence of P-gp inhibitors on mangiferin(1) The blood drug concentration of P-gp inhibitor (verapami1 and cyclosporine A) group was significantly increased in comparison to the mangiferin monomer group. The time to peak is delayed in the P-gp inhibitor group. There was significant statistical difference between the absorption of mangiferin in monomer and composition (P>0.05), which suggesting that the mangiferin may be the substrate of the P-gp.(2) The Peff and Ka values of mangiferin were significantly increased in the P-gp inhibitor (Verapamil) group. The results of One-Way ANOVA suggest that verapamil can improve the absorption of mangiferin in the ileum and jejunum. The Peff and Ka values of mangiferin were slight increased in the P-gp inhibitor (cyclosporin A) in the jejunum (P>0.05). The absorption of mangiferin was significantly increased in the P-gp inhibitor (cyclosporin A) group in comparison to the P-gp inhibitor (Verapamil) group, which suggesting that the mangiferin may be the substrate of the P-gp.(3)Adding the P-gp inhibitor varapamil and cyclosprine into examine probational liquid, all the value of the Papp were significant increased both in the direction of AP to BL and BL to AP. Meanwhile, the efflux rates (ER) were decreased in varying degrees, which showing that the inhibitors of P-gp could significantly affect the intestinal absorption of the mangjferin.2. The influence of MRP2 inhibitors on mangiferin(1)The blood drug concentration of MRP2 inhibitor (indomethacin) group was significantly increased in comparison to the mangiferin monomer group. The time to peak is delayed in the MRP2 inhibitor (indomethacin) group. The maximum plasma concentration (cMAX) and area under the curve (AUCOâ†', AUCOâ†'∞) were slight increased in MRP2 inhibitor (indomethacin) group. However, there was no significant statistical difference between the absorption of mangiferin in monomer group and MRP2 inhibitor (indomethacin) group. The time to peak (Tmax) was increase from 0.55h to 1.95h (P< 0.05), which suggesting that the inhibitors of MRP2 could significantly improve the intestinal absorption of the mangiferin.(2) The Peff and Ka values of mangiferin in the jejunum were increased in the MRP2 inhibitor (indomethacin) group, which no statistically differ from those of the mangiferin monomer group. The Peff and Ka values of mangiferin in the ileum were significantly increased in the MRP2 inhibitor (indomethacin) group (P< 0.05), which suggesting that the mangiferin may be the substrate of the MRP2 and indomethacin can improve the intestinal absorption of mangiferin.Conclusion:In this paper, pharmacokinetics, in-situ single pass perfusion model and the MDCK-MDR1 cells monolayer model were applied to investigate the relation between the absorption of mangiferin and P-gp inhibitors. The experiment results show that the efflux of P-gp can influence the absorption of mangiferin. Both P-gp and MRP2 can improve the absorption of mangiferin in the ileum and jejunum. Pharmacokinetics, in-situ single pass perfusion models were applied to study the effects of MRP2 inhibitors on the absorption of mangiferin, which suggesting that there is a close relation between MRP2 inhibitors and the absorption of mangiferin. MRP2 inhibitor (indomethacin) can improve the intestinal absorption of mangiferin. The experiment results also show that the bioavailability of mangiferin is closely related to P-gp and MRP2 and mangiferin may be the substrate of P-gp and MRP2.