Effect of bioadhesive excipients on absorption of total flavonids from Puerariae Lobatae Radix transporting across Caco-2 cell monolayer

Abstract

ObjectivePueraria total flavonids (PTF) can treat cardiovascular and cerebrovascular diseases, but it has poor membrane permeability and oral bioavailability. Some excipients, such as carbomer, chitosan, and hydroxypropyl methylcellulose, can improve the oral bioavailability. Traditional in vitro evaluation techniques, including the rat intestinal perfusion and cell line models, cannot evaluate PTF absorption and holistic transporters. MethodsThis study evaluated excipients’ adhesiveness and effect on PTF transport across Caco-2 cell monolayer. cDNA microarrays identified gene expression changes in Caco-2 cells exposed to PTF and PTF with excipients, and revealed the mechanism underlying the effect of excipients on PTF absorption. ResultsIn vitro adhesion and transport experiments across Caco-2 showed that excipients had higher adhesiveness to gastric mucosa and transport efficiency across Caco-2 cells than PTF alone. The interaction of PTF with excipients significantly changed the expression of some genes, which might influence the absorption rate of PTF. ConclusionDifferent bioadhesive polymers can improve intestinal absorption of PTF, which was related to some genes affiliated to the ATP-binding cassette (ABC) and solute carrier transporter (SLC) to some extent.