Isolation and lipolytic activity of eurycomanone and its epoxy derivative from Eurycoma longifolia

Eurycomanone (1) and 13 beta,21-epoxyeurycomanone (2) were isolated from Eurycoma longifolia for studies of lipolytic activity. Compound 1 enhanced lipolysis in adipocytes with an EC50 of 14.6 M, while its epoxy derivate, compound 2, had a stronger activity with an EC50 of 8.6 M. Based on molecular mechanistic study using several specific inhibitors to lipolytic signaling pathways, it was found that PKA inhibitor totally diminished the lipolytic activity of 1 and 2. Further immunoblotting analysis confirmed the activation of phosphorylated PKA by both 1 and 2. With the growing need to develop new anti-obesity agents, eurycomanone and its epoxy derivate can be used as promising lead compounds to target lipid catabolism. (C) 2017 Elsevier Ltd. All rights reserved.