Glucuronidation, oxidative metabolism, and bioactivation of enterolactone in rhesus monkeys

Abstract

Enterolactone (ENL) and enterodiol (END) are mammalian lignans derived from the plant lignans matairesionol (MAT), secoisolariciresinol (SECO), and other dietary precursors. ENL was found to undergo extensive glucuronidation with rhesus liver microsomes to form O-glucuronides at both phenolic hydroxy groups. In addition to glucuronidation, ENL was found to be a good substrate for oxidative metabolism. The major products had a m/z of 313 or 295 by LC-MS analysis in negative ion mode and were determined to be products of monohydroxylation of ENL. The m/z 295 products were the result of a dehydration of the m/z 313 in the MS source. Addition of N-acetylcysteine (NAC) to the NADPH incubations re..