Abstract:

BACKGROUND: To date, there are few researches on the effect of caffeic acid on the formation and differentiation of osteoclasts, and fewer researches on the mechanism of osteoclastic bone resorption.
OBJECTIVE: To explore the mechanism of sweet potato extract caffeic acid inhibiting osteoclastic bone resorption by studying the effect of caffeic acid on the formation and differentiation of osteoclast and on the expression of cathepsin K gene.
METHODS: Caffeic acid effects on formation and differentiation of osteoclasts in three osteoclast cell lines were observed and the inhibition effect of caffeic acid on the expression of cathepsin K gene was detected by reverse transcription-PCR.
RESULTS AND CONCLUSION: Caffeic acid could directly inhibit the formation and differentiation of osteoclasts in three osteoclast cell lines. Caffeic acid had no influences on the expression of receptor activator of nuclear factor-kappa B ligand and receptor activator of nuclear factor-kappa B mRNA, but could markedly inhibit the expression of cathepsin K gene based on the semi-quantitative gene analysis of reverse transcription-PCR. Caffeic acid, an effective component of sweet potato extract, cannot only directly inhibit the formation and differentiation of osteoclast, but also markedly inhibit the expression of cathepsin K gene, which seems to be the mechanism of sweet potato extract inhibiting osteoclastic bone resorption.