AbstractsBiology & Animal Science

We investigated the effect of the natural polyphenols rosmarinic acid and arbutin on osteoclast differentiation in RAW 264.7 cells. Rosmarinic acid and arbutin suppressed osteoclast differentiation and had no cytotoxic effect on osteoclast precursor cells. Rosmarinic acid and arbutin inhibited superoxide production and intracellular superoxide in a dose dependent manner. mRNA expression of the master regulator of osteoclastogenesis, nuclear factor of activated T cells cytoplasmic1(NFATc1), and the osteoclast marker genes, matrix metalloproteinase -9, tartrate-resistant acid phosphatase and cathepsin-K, decreased after treatments with rosmarinic acid and arbutin. Furthermore, resorption activity decreased with the number of osteoclasts. These results suggest that rosmarinic acid and arbutin may be useful for the prevention and treatment of bone diseases such as osteoporosis through mechanisms involving inhibition of superoxide and down-regulation of NFATc1.