Downregulation of Aquaporin 3 Mediated the Laxative Effect in the Rat Colon by a Purified Resin Glycoside Fraction from Pharbitis Semen. (13th January 2019)

• Record Type: Journal Article
• Authors: Zhu, Dongrong; Chen, Chen; Bai, Lijuan; Kong, Lingyi; Luo, Jianguang
• Other Names: Martinotti Simona Academic Editor.
• Is Part Of: Evidence-based complementary and alternative medicine. Volume 2019(2019)
• Publication Date: 2019-01-13
• Subjects: Alternative medicine -- Periodicals; 615.505
• DOI: 10.1155/2019/9406342
• Languages: English
• ISSNs: 1741-427X

Abstract

Abstract : Background . Pharbitis Semen, the seeds of Pharbitis nil, is widely used as a traditional purgative medicine in China, Korea, and Japan. This study investigated the laxative effects of a purified resin glycoside fraction obtained in our previous study from Pharbitis Semen in vivo and in vitro. Materials and Methods . After orally administering a purified resin glycoside fraction from Pharbitis Semen (RFP) to rats, the content of fecal water, AQP3, NF- κ B, COX-2 expression, and the prostaglandin E2 (PGE2 ) concentrations in the colon were examined. Moreover, human intestinal epithelial cells (HT-29) were used to investigate the mechanism of RFP decreasing the AQP3 expression. Results . Results obtained showed that treatment with RFP increased the feces excretion and fecal water content of rats in a dose-dependent manner. More interestingly, AQP3 expression was suppressed by RFP treatment both in the rat colons and in HT-29 cells, while the NF- κ B pathway-mediated PGE2 production was activated. Interestingly, pretreating rats with BAY-11-7082 (NF- κ B inhibitor) or indomethacin (COX-2 inhibitor) and RFP neither induced diarrhea nor decreased the AQP3 expression in the colon. Conclusions . The purgative property of the purified resin glycoside fraction was attributed to NF- κ B activation in the colon, which increased the COX-2-mediated secretion of PGE2 . PGE2 decreased AQP3 expression which inhibits water absorbed from the intestine to the blood vessel side, resulting in the laxative effect of RFP.