miR-376c-3p mediates icariin’s anti-osteoclastogenic effect by targeting Mmp3

BACKGROUND: MicroRNAs (miRNAs) are crucial regulators of osteoclast differentiation. Icariin (ICA), the primary active constituent of the traditional Chinese herb Epimedium, has been shown to inhibit osteoclastogenesis. However, whether ICA suppresses osteoclast differentiation via miRNA regulation remains to be elucidated. METHODS: We employed bioinformatic analysis coupled with in vivo validation to screen for and identify potential targets that mediate the effects of ICA on osteoclast formation. Subsequently, we carried out in vitro experiments involving the overexpression and knockdown of miR-376c-3p in bone marrow-derived macrophages (BMMs). Additionally, luciferase reporter assays and western blot analysis were utilized to ascertain the direct targets of miR-376c-3p. RESULTS: It was confirmed that miR-376c-3p plays a regulatory role in osteoclast differentiation within bone marrow-derived macrophages (BMMs). Notably, the knockdown of miR-376c-3p led to a partial reversal of the inhibitory effect that ICA exerts on osteoclastogenesis. Furthermore, matrix metalloproteinase-3 (Mmp3) was validated as a direct target of miR-376c-3p, providing evidence to suggest that ICA likely mediates its effects through the miR-376c-3p/Mmp3 signaling axis. CONCLUSION: Our findings demonstrate that ICA exerts its anti-osteoporotic effect by downregulating the miR-376c-3p-mediated Mmp3 expression. This study provides insights that potentially facilitate ICA's clinical application.