Han Na, Xu Jinghua, Xu Feng, Liu Zhihui, Yin Jun
Development and Utilization Key Laboratory of Northeast Plant Materials, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China.
School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang 110016, China.
J Ethnopharmacol. 2016 Jun 5;185:53-9. doi: 10.1016/j.jep.2016.03.033. Epub 2016 Mar 12.
In traditional Chinese medicines, osteoporosis was considered to be induced by the deficiency of kidney's function. The Rhizoma of Dioscorea spongiosa was one of the kidney tonifying and bone strengthening agent in the traditional usage and previous study had shown that its 90% ethanol fraction was effective on anti-osteoporosis using the ovariectomized (OVX) rats. However, for the secondary osteoporosis, like glucocorticoid-induced osteoporosis (GIO), its effect was still unknown.
The GIO model was established by injecting dexamethasone into the muscles of rats. The 90% ethanol extraction of Dioscorea spongiosa (DSE) were administrated to rats in three different dosages, 125, 250 and 500mg/Kg/d, respectively. After the administration, the rats were sacrificed to measure different kinds of indicators, including the biochemical indexes in urine and serum, the bone tissue metrology, BMC and BMD, biomechanical indicators and histological changes.
DSE could significantly reduce the content of BGP, ALT, TRAcP, HOP/Cr and Ca/Cr, increase the content of P/Cr compared with the control group, suggesting that DSE is effective on controlling the excessive transition of bones and inhibiting the bone resorption. By the administration of DSE, the dry bone weight/volume, ash weight/volume, the content of Ca, BMD and BMC were also obviously increased, suggesting that DSE could increase the bone mass by increasing its Ca content. Besides, the flexure strength and maximum bending force could be improved by DSE, suggesting that it could strengthen the hardness and strength of bones. In the histological investigation, DSE could repair the broken of cancellous bones and bone trabecular with the similar activity with XLGB.
The results showed that DSE is effective on inhibiting GIO in rats by improving the bone tissue metrology, BMC and BMD as well as biomechanical indicators, and also repairing the microscopic changes of cancellous bones and trabecular bones. The mechanism was related to the inhibition of excessive bone transition and bone resorption according to the changes of biochemical indexes.
在传统中药中，骨质疏松症被认为是由肾功能亏虚所致。绵萆薢是传统用药中补肾壮骨的药物之一，先前的研究表明其90%乙醇提取物对去卵巢（OVX）大鼠的抗骨质疏松有效。然而，对于继发性骨质疏松症，如糖皮质激素诱导的骨质疏松症（GIO），其效果仍不清楚。
通过向大鼠肌肉注射地塞米松建立GIO模型。将绵萆薢90%乙醇提取物（DSE）以三种不同剂量分别给予大鼠，即125、250和500mg/Kg/d。给药后，处死大鼠以测量各种指标，包括尿液和血清中的生化指标、骨组织计量学、骨矿含量（BMC）和骨密度（BMD）、生物力学指标以及组织学变化。
与对照组相比，DSE可显著降低骨钙素（BGP）、谷丙转氨酶（ALT）、抗酒石酸酸性磷酸酶（TRAcP）、羟脯氨酸/肌酐（HOP/Cr）和钙/肌酐（Ca/Cr）的含量，增加磷/肌酐（P/Cr）的含量，表明DSE对控制骨质过度转换和抑制骨吸收有效。通过给予DSE，干骨重量/体积、灰分重量/体积、钙含量、BMD和BMC也明显增加，表明DSE可通过增加钙含量来增加骨量。此外，DSE可提高弯曲强度和最大弯曲力，表明其可增强骨骼的硬度和强度。在组织学研究中，DSE可修复松质骨和骨小梁的破损，其活性与仙灵骨葆相似。
结果表明，DSE可通过改善骨组织计量学、BMC和BMD以及生物力学指标，修复松质骨和骨小梁微观变化，有效抑制大鼠GIO。根据生化指标变化，其作用机制与抑制骨质过度转换和骨吸收有关。
