Enhanced metabolic bioavailability of tetrahydrocurcumin after oral supplementation of a γ-cyclodextrin curcumin complex

Abstract

Tetrahydrocurcumin, curcumin’s main metabolite, exhibits properties similar to curcumin with superior effectiveness in certain categories. However, as curcumin’s bioavailabilty and in vivo conversion are low, formulations yielding appreciable tetrahydrocurcumin concentrations are required to convey potential health benefits either through tetrahydrocurucmin itself, complementary or synergistic to curcumin.Here, we conducted a study with humans orally receiving γ-cyclodextrin complexed curcumin for 12 weeks daily and analyzed the metabolic bioavailability of tetrahydrocurcumin. Notably, supplementation yielded threefold higher serum tetrahydrocurcumin compared to curcumin already after 4 weeks. In fact, this is in line with previously unpublished data demonstrated here revealing an increased metabolic bioavailability (BA = 39.8) of tetrahydrocurcumin.Foremost we show that γ-cyclodextrin enhances the oral and metabolic bioavailability of curcumin and tetrahydrocurcumin, respectively. This is likely related to an improved uptake of cyclodextrin complexed curcumin corroborated by enclosed in vitro studies, its metabolic turnover and the prolonged plasma half-life of tetrahydrocurcumin.

Keywords

• Tetrahydrocurcumin
• Curcumin
• Cavacurmin
• γ-cyclodextrin
• Bioavailability
• Human