Bone-Protective Role of Bupleurum in a Rat Model of Postmenopausal Osteoporosis

The protocol aims to investigate the effects of Chai hu administration on postmenopausal osteoporosis in ovariectomized (OVX) rats. Eight-week-old female Sprague-Dawley rats underwent bilateral ovariectomy using the dorsal approach to establish a postmenopausal osteoporosis model. Different doses of Chai hu oral liquid were administered by oral gavage for 12 consecutive weeks, followed by evaluations of bone microstructure and measurements of inflammatory cytokine levels. Medium- and high-dose Chai hu treatment partially inhibited bone loss, reduced pro-inflammatory cytokine expression, and upregulated anti-inflammatory cytokine levels in OVX rats. There was a significant reduction in the severity of bone destruction from low to high doses, and dose-related improvements in bone microstructural reconstruction were observed. Chai hu mitigated estrogen deficiency-induced bone loss and microstructural deterioration, thereby suppressing OP progression in this OVX model. This was likely to have resulted from the anti-inflammatory effects of the pathways involved.