In vitro transport studies of Hawthorn procyanidins by Caco-2 monolayers: transport and efflux

Extracts from Hawthorn (Crataegus sp.) are considered as a rational based phytomedicine for declining cardiac performance, with flavonoids and procyanidins as active compounds. Especially oligomeric procyanidins (OPC) are assessed to have the most marked pharmacodynamic effects. Detailed investigations on the bioavailability of procyanidins after oral ingestion are not available. The current study was designed to investigate the absorption of OPC from different fractions/extracts of Crataegi folium cum flore using validated monolayers of the human Caco-2 cell line grown in Transwells. Respective concentrations of distinct OPC clusters were determined in the basolateral and apical compartments and in cell lysates of Caco-2 cells. Quantitation was performed by HPLC on diol stationary phase with fluorescence detection.