The Effects Of Liuwei Dihuang On Canonical Wnt/β-catenin Signaling Pathway In Prevention Of Osteoporosis Induced By Ovariectomy

Objective To observe the effects of Liuwei Dihuang (LWDH) on Wnt/(3-catenin signaling pathway in prevention of osteoporosis induced by ovariectomy in rats.Methods 45 female SD rats were randomly divided into three group (n=15):sham group, model group and LWDH group. The rats in model group and LWDH group were ovariectomized (OVX), whereas sham operation was performed in sham group. The successful model of osteoporosis was confirmed after three months by histomorphology. Then the rats in LWDH group were given LWDH by intragastric administration and 0.9% normal saline was used in sham group and model group. After three months of treatment, the rats were put to death in batch. The changes of bone mineral density (BMD), histomorphology and biomechanics were measured, the expression of Lrp-5, β-catenin, Runx2, Osx mRNA involving the Wnt/β-catenin signaling pathway were tested by RT-PCR.Results ①BMD:compared with sham group, the BMD of femurs and lumbar vertebra in model group were decreased significantly (P<0.05). Compared with model group, the BMD of femurs and lumbar vertebra in LWDH group were increased significantly (P<0.05). There was no difference between sham group and LWDH group (P>0.05).②Histomorphology:in model group, we found disordered trabeculae, significantly reduced and thinning trabeculae and slight fractures in femurs, while the femurs in LWHD group showed slightly ordered arrangement of trabeculae, slightly thinning of trabeculae and none obvious slight fractures, which is similar to sham group. ③Biomechanics:compared with sham group, the maximum loading and elastic modulus of lumbar vertebra in model group were decreased significantly (P<0.05). Compared with model group, the maximum loading and elastic modulus of lumbar vertebra in LWDH group were increased significantly (P<0.05). There was no difference between sham group and LWDH group (P>0.05). ④RT-PCR:compared with sham group, the expression of Lrp-5, β-catenin, Runx2, Osx mRNA of femur in model group were decreased significantly (P<0.05). Compared with model group, the expression of Lrp-5, β-catenin, Runx2, Osx mRNA of femur in LWDH group were increased significantly (P<0.05). There was no difference between sham group and LWDH group (P>0.05).Conclusion ①Liuwei Dihuang could prevent osteoporosis induced by ovariectomy; ②On activation of the canonical Wnt/β-catenin signaling pathway may be one of the mechanisms of treatment of osteoporosis.