Bioavailability of procyanidin dimers and trimers and matrix food effects in in vitro and in vivo models

Abstract

Among procyanidins (PC), monomers, such as catechin and epicatechin, have been widely studied, whereas dimer and trimer oligomers have received much less attention, despite their abundance in our diet. Recent studies have showed that as dimers and trimers could be important in determining the biological effects of procyanidin-rich food, understanding their bioavailability and metabolism is fundamental. The purpose of the present work is to study the stability of PC under digestion conditions, the metabolism and the bioavailability by using a combination of in vitro and in vivo models. Simultaneously, the matrix effect of a carbohydrate-rich food on the digestibility and bioavailability of PC is investigated. The results show a high level of stability of PC under gastric and duodenal digestion conditions. However, the pharmacokinetic study revealed limited absorption. Free forms of dimers and trimers have been detected in rat plasma, reaching the maximum concentration 1 h after oral intake of a grape seed extract.

The present work was supported by the CENIT program from the Spanish Minister of Industry and by a consortium of companies led by La Morella Nuts S.A. (Reus, Catalonia, Spain) with the following companies: Shirota Functional Foods, S.L.; KRAFT; BTSA, Biotecnologı´as Aplicadas, S.L.; Seleccio ´n Batalle´, S.A.; Industrial Te´cnica Pecuaria, S.A.; Neuron BioPharma, S.A.; Grupo Leche Pascual, S.A.U.; Innaves, S.A. The present work was also supported by the Spanish Ministry of Education and Science financing the project AGL2008-00 387.