In vitro hepatic metabolism of curcumin diethyl disuccinate in different animal species

Abstract

Curcumin diethyl disuccinate (CDD) is an ester prodrug of the active compound, curcumin. CDD has been improved chemical stability and intestinal permeability more than curcumin. CDD demonstrated biological activity higher than curcumin. The aim of this study is to investigate a suitability of using liver S9 fraction (LS9) in drug metabolism profiling as function of animal sources of enzyme regarding possible translation of in vitro outcome to clinical study. The metabolites, in vitro kinetics and esterase enzyme involved in CDD hydrolysis by LS9 of human, monkey, dog and rat ware determined. The high-performance liquid chromatography conjugated with high-resolution mass spectrometry-based methodologies indicated that CDD was hydrolysed to curcumin through the monoethylsuccinyl curcumin. Ultra-high-performance liquid chromatography analysis was used to determined kinetic parameters, including degradation rate constants, half-lives and hepatic intrinsic clearances. The hydrolysis profile of CDD was similar in all test species and showed a two-step, consecutive, pseudo-first-order irreversible reaction. CDD was rapidly metabolized in LS9 of all test species and ranked as human > dog > monkey > rat. The predicted clearance of CDD in liver might be ranked as dog > monkey > rat > human. The identification of CDD hydrolyzing enzymes from HLS9, MLS9, DLS9 and RLS9 evaluated by the effect of specific esterase inhibitor. Carboxylesterase was identified as the major hepatic enzyme responsible for CDD hydrolysis in LS9 of four species, followed by butyrylcholinesterase. The in vitro hepatic metabolism outcomes would be of benefit to future in vivo studies and the clinical translation of the ester CDD prodrug.