Administration time significantly affects plasma bioavailability of grape seed proanthocyanidins extract in healthy and obese Fischer 344 rats.

SCOPE: Phenolic compounds are bioactive molecules that are associated with several health benefits. Metabolization and absorption are the main determinants of their bioavailability and bioactivity. Thus, the study of the factors that modulate these processes, such as sex or diet is essential. Recently, it has been shown that biological rhythms may also play a key role. Hence, the aim of this study was to evaluate if the bioavailability of a grape proanthocyanidin extract (GSPE) is affected by the administration time in an animal model of metabolic syndrome (MetS).

METHODS AND RESULTS: Female and male Fischer 344 rats were fed either a standard or a cafeteria diet (CAF) for 9 weeks, and an oral dose of GSPE (25 mg/kg) was daily administered either at 8:00 am (ZT-0) or at 8:00 pm (ZT-12) during the last 4 weeks. Plasma phenolic compounds were then quantified by HPLC-ESI-MS / MS. Phase-II and gut microbiota-derived phenolic metabolites were affected by ZT in all conditions or only in obese rats, respectively. CAF feeding affected the bioavailability of phenolic acids and free flavan-3-ols. Differences due to sex were also observed.

CONCLUSION: These findings demonstrate that ZT, diet and sex are key factors influencing phenolic compounds bioavailability. This article is protected by copyright. All rights reserved.