Absorption characteristic of paeoniflorin-6′-O-benzene sulfonate (CP-25) in in situ single-pass intestinal perfusion in rats

Abstract

1. Paeoniflorin-6′-O-benzene sulfonate (CP-25) was synthesized to improve the poor oral absorption of paeoniflorin (Pae).

2. This study was performed to investigate the absorptive behavior and mechanism of CP-25 in in situ single-pass intestinal perfusion in rats, using Pae as a control.

3. The results showed that intestinal absorption of CP-25 was neither segmental nor sex dependent. However, the main segment of intestine that absorbed Pae was the duodenum. Furthermore, passive transport was confirmed to be the main absorption pattern of CP-25. More importantly, the absorption of CP-25 was much higher than Pae in the small intestine.

4. Among the ABC transporter inhibitors, the absorption rate of Pae increased in the presence of P-gp inhibitors verapamil and GF120918, which indicated that Pae was a substrate of P-glycoprotein (P-gp), however, such was not observed in the presence of breast cancer resistance protein and multidrug resistance-associated protein 2. Finally, the ABC transporter inhibitors did not have any significant impact on CP-25 as demonstrated in the parallel studies.

5. CP-25 could improve the poor absorption of Pae, which may be attributed to both the lipid solubility enhancement and its resistance to P-gp-mediated efflux.

• ABC transporters
• drug transport
• intestinal absorption
• paeoniflorin
• paeoniflorin-6′-O-benzene sulfonate
• P-glycoprotein

Acknowledgements

The authors thank Prof. Wei Wei for designing, guiding, and critical reading of the manuscript and also for his helpful suggestions.

Declaration of interest

This work was financially supported by the National Natural Science Foundation of China (No. 81330081, No. 81173075, No. 81302845), the Anhui Province Nature Science Foundation in University (No. KJ2013A158), and the Grants for Scientific Research of BSKY (No. XJ201211) from Anhui Medical University. The authors report no conflicts of interest.

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