Abstract
This study characterized the intensive suppressive effects of α-lipoic acid (LA) and cinnamaldehyde (CA) on excessive osteoclastogenesis, specifically in the suppression of the nuclear factor of activated T cell 1 (NFATc1) expression, which acts a master transcriptional regulator of osteoclastogenesis. We confirmed that LA inhibited NFATc1 expression in the receptor activator of nuclear factor-κB ligand-stimulated RAW264.7 cells at concentrations of 50-100 μmol/L and that LA inhibited mature osteoclast formation. To enhance the effects of LA, we assessed the effects of LA when combined with CA. We found that a formulation containing 50 μmol/L LA and 5 μmol/L CA significantly suppressed both NFATc1 expression and mature osteoclast formation, in contrast to significant inhibition with 100 μmol/L LA or 10 μmol/L CA alone. Our results suggest that concomitant use of LA with CA may have therapeutic application for multiple bone disorders.
