Methyl Ganoderic Acid DM: A Selective Potent Osteoclastogenesis Inhibitor

Abstract

Increased osteoclastic bone resorption plays a central role in the pathogenesis of many bone diseases, and osteoclast inhibitors are the most widely used treatments for these diseases. Ganoderic acid DM, the main component of Ganoderma lucidum , has been known for its medicinal effects such as anti-androgen and anti-proliferative activities. In this study, we investigated the inhibitory effects of ganoderic acid DM and its analog (methyl ganoderic acid DM and 7-oxo-methyl ganoderic acid Z) on osteoclastogenesis using RAW264 cell in vitro . Methyl ganoderic acid DM blocked osteoclastogenesis completely at 12.5 μM with low cytotoxicity less than 30%. On the other hands, ganoderic acid DM blocked osteoclastogenesis completely at the higher concentration of 50 μM, but 7-oxo-methyl ganoderic acid Z did not up to 100 μM. These results implicated the carbonyl group at C-3 is essentially for selective osteoclastogenesis inhibitory activity, and methyl esters at C-26 should play an important role in enhancing its osteoclastogenesis inhibitory activity