| Objective To study the effect of rhizoma drynariae on RANKL/OPG and osteoclast differentiation by bone marrow stromal cells (BMSCs) in postmenopausal osteoporotic rats, and to explore its possible mechanism. Methods Experimental rats were divided into experimental group (OVXDF, ovariectomized and rhizoma drynariae gavage), model group (OVX, ovariectomized and 0.9% NaCl gavage), and sham operation group (SHAM, sham surgery and 0.9% NaCl gavage). After successful modeling, BMSCs were extracted. BMSC and bone marrow mononuclear cells were co-cultured in the upper and lower chambers of the Transwell chamber, respectively. The co-cultured cells were divided into experimental group + osteoclasts (OVXDF+OC), model group + osteoclasts (OVX+OC), and sham operation group + osteoclasts (SHAM+OC). The differentiation and maturation of osteoclasts were observed and counted with a phase-contract microscope. OPG and RANKL in the culture medium of the lower chamber were detected using ELISA method. mRNA and protein expressions of Wnt10b, β-Catenin, RANKL, and OPG in BMSCs were detected using PCR and Western blotting. Results In the co-culture systems, the number of osteoclasts in OVXDF+OC group was significantly less than in OVX+OC group (P<0.05). OPG content in the culture medium of the lower chamber and the expression of wnt10b, β-Catenin, and OPG in the co-culture systems were the lowest, but RANKL and RANKL/OPG were the highest, in OVX+OC group. After rhizoma drynariae gavage, OPG content in OVXDF+OC medium and mRNA and protein expressions of Wnt10b, β-Catenin, and OPG in BMSCs increased significantly (P<0.05), but RANKL content and RANKL/OPG decreased significantly (P<0.05). Conclusion Rhizoma drynariae regulates the expression of OPG and RANKL, and activates OPG/RANKL/RANK signaling pathway to inhibit the differentiation and maturation of osteoclasts in BMSCs. This effect may be related to the activation of Wnt/β-Catenin signaling pathway in BMSCs. |