In vitro intestinal transport and anti-inflammatory properties of ideain across Caco-2 transwell model

Abstract

The aim of the study was to investigate the absorption and transport mechanisms as well as the anti-inflammatory properties of ideain on Caco-2 transwell model. A concentration and time-dependent bidirectional transport was highlighted; despite this, a clear saturation of the transepithelial absorption in the A-B direction was observed at ideain concentration > 10 μM, suggesting an involvement of membrane transporters. Comparing Papp and PDR values of ideain (10 μM) to reference drugs with a low to a high apparent permeability, it is possible to predict a low in vivo absorption, with a transport efficiency of 1.03%. Co-treatments with several EDTA-Na₂ concentrations (1-5 mM) and P-gp inhibition studies with verapamil 100 μM ruled out a passive diffusion of this molecule as well the possibility that P-gp could affect ideain absorption. Inhibition studies using 2 mM phloridzin (SGLT1 inhibitor) and 2 mM phloretin (GLUT2 inhibitor), showed a clear SGLT1 and GLUT2 involvement in the ideain absorption, with SGLT1, which plays the pivotal role. Finally, preliminary anti-inflammatory studies showed that ideain is able to modulate, at a pharmanutritional dose, and with a comparable activity in respect to the reference drug dexamethasone (10 μM), the LPS-induced inflammation in Caco-2 transwell model, which makes it a potentially useful molecule for nutraceutical purpose.

Keywords: Absorption; Anti-inflammatory activity; Caco-2 transwell model; Glucose transporters; Ideain; Transport.