Improved blood–brain-barrier permeability and tissue distribution following the oral administration of a food-grade formulation of curcumin with fenugreek fibre

Abstract The delivery of significant concentrations of biologically active free curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin) at the target tissues has always been regarded as a major limitation for the efficacy of curcumin. Herein we report the blood–brain-barrier permeability, tissue distribution and enhanced bioavailability of free curcuminoids following the oral administration of a food grade curcumin formulation in comparison with the standardized native curcumin, for the first time. UPLC-ESI-MS/MS analyses of post-administration tissue samples of Wistar rats (200 mg/kg body weight) demonstrated significant ( p  0.001) enhancement in plasma bioavailability (25-fold), in vivo stability and blood–brain-barrier permeability as evidenced from the tissue distribution of free curcuminoids at, (ng/g), brain (343 ± 64.7), heart (391.7 ± 102.5), liver (445.52 ± 83), kidney (240.1 ± 47.2), and spleen (229.72 ± 42.2), with extended elimination half-life of 3 to 4 h. Standard curcumin, on the other hand, detected only 1.4 ± 0.8 ng/g of curcumin in the brain tissues.