Objective: Hormone replacement therapy has been used as an effective treatment for the prevention of bone loss in postmenopausal women. In our previous study, QiBaoMeiRan formula (QBMR) had estrogenic activity and could relieve symptoms of hot flushes and body weight increase induced by estrogen decline. However, no evidence base links QBMR to preventing bone loss. The aim of this study is to investigate the effect of QBMR on bone loss.
Methods: The ovariectomized rat model was established, and ovariectomized rats were treated with QBMR at doses of 0.875, 1.75, and 3.5 g/kg per day for 8 weeks. Biochemical parameters, bone mineral density, structural morphometric traits and histological characteristics of trabecular bone were assessed.
Results: QBMR treatment significantly decreased the increase in serum alkaline phosphatase, bone Gla-protein and C-telopeptide fragments of type I collagen and decreased the decline of serum calcium and phosphorus in the circulation of ovariectomized rats. QBMR completely corrected the decrease in bone mineral density in lumbar vertebrae (L4-L6) comparable to the sham group. In addition, QBMR treatment also significantly ameliorated the decrease of structural parameters of femur trabecular bone, bone volume fraction, trabecular number, trabecular thickness and bone mineral density as well as the increase in trabecular separation by micro-computerized tomography scanning. These were also confirmed by bone histological results that showed its protective action.
Conclusions: Our results indicated that QBMR had a definite anti-bone loss effect and will have potential to be used for the treatment of postmenopausal osteoporosis.
Keywords: Bone loss; Qibaomeiran formula; bone mineral density; micro-CT; ovariectomy.