女贞子对去卵巢大鼠抗骨质疏松作用及其对GH/IGF-1信号通路的影响

Antiosteoporosis effect of Ligustrum lucidum on ovariectomized rats and its effect on GH/IGF-1 signaling pathway

目的探讨女贞子抗骨质疏松的作用与生长激素(GH)/胰岛素样生长因子1(IGF-1)信号通路的关系。方法去卵巢大鼠给予女贞子水提液干预14周后,分别用苏木素-伊红(HE)染色和番红O/固绿染色评价股骨骨微结构的变化,micro-CT扫描测定骨组织形态计量学参数和骨密度(BMD),ELISA法测定血清GH水平,Western blotting和免疫组织化学染色法测定肝脏和骨中IGF-1蛋白表达水平。结果女贞子能防止去卵巢诱发的大鼠股骨骨小梁形态破坏,抑制大鼠BMD和股骨糖胺聚糖含量的降低。同时,女贞子可明显抑制去卵巢大鼠血清GH水平的下降,提高IGF-1蛋白在去卵巢大鼠肝脏和骨中的表达。结论女贞子可能是通过调节GH/IGF-1信号通路抑制骨量丢失和改善骨微结构,从而发挥抗骨质疏松的作用。

Objective To investigate the relationship between the anti-osteoporotic effect of Ligustrum lucidum and the growth hormone(GH)/insulin-like growth factor 1(IGF-1) signaling pathways. Methods L. lucidum aqueous extract was orally administrated to ovariectomized(OVX) rats for 14 weeks. Then the femurs were removed and stained with hematoxylin & eosin(HE) and Safranin O/Fast Green staining, respectively, to evaluate the change of bone microstructure. The histomorphological parameters and bone mineral density(BMD) of the femurs were measured by micro-CT. Furthermore, rat serum GH level was determined by ELISA assay,and IGF-1 protein expression in liver and bone was determined by Western blotting and immunohistochemical staining. Results L.lucidum prevented the disorganized femoral trabeculae and inhibited the decrease in BMD and glycosaminoglycan content in OVX rats. In addition, L. lucidum significantly inhibited the decrease of serum GH levels and improved IGF-1 protein expression of liver and bone in OVX rats. Conclusion L. lucidum may prevent against osteoporosis through inhibition of bone loss and improvement of bone microstructure via regulating GH/IGF-1 signaling pathway.