Icariin-induced myocilin upregulation promotes osteogenic differentiation of human periodontal ligament stem cells through BMP2-WNT/beta-catenin pathway

This study aimed to investigate the impact of icariin on the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) and elucidate the underlying mechanisms. hPDLSCs were isolated and exposed to different concentrations of icariin. Osteogenic differentiation was assessed by calcium deposit staining and expression of osteogenic markers. Additionally, RNA sequencing was used to analyze transcriptome variations induced by icariin. The expression of identified molecule determinants was modulated to validate their osteogenic effects, and the signaling pathways involved were confirmed through analysis of key intermediates and the application of specific inhibitors. Icariin-treated hPDLSCs displayed a dose-dependent upregulation of mineralization and the increased expression of osteogenic markers such as RUNX2, ALP, OCN and BMP2, indicating improved osteogenic differentiation potential. Icariin was confirmed to significantly upregulate the expression of myocilin (MYOC) and activate the BMP2-WNT/beta-catenin pathway of hPDLSCs. Furthermore, myocilin knockdown or inhibition of the BMP2-WNT/beta-catenin pathway by Noggin and DKK1 attenuated the osteogenic effects of icariin, which were enhanced by myocilin overexpression. This study demonstrates that icariin promotes osteogenic differentiation of hPDLSCs, primarily mediated through myocilin overexpression and activation of the BMP2-WNT/beta-catenin pathway. The findings hold significant implications for developing novel therapeutic strategies for periodontal diseases.