淫羊藿素和脱水淫羊藿素对骨髓间充质干细胞成骨性分化影响的比较研究

 目的 比较研究淫羊藿素和脱水淫羊藿素对体外培养大鼠骨髓间充质干细胞（rat bone marrow stromal cells，rBMSCs成骨性分化的影响。方法 贴壁筛选法体外培养rBMSCs，以1×10-5 mol·L-1的淫羊藿素和脱水淫羊藿素对rBMSCs的成骨性分化进行药物干预，比较淫羊藿素组、脱水淫羊藿素组以及不加药的对照组之间碱性磷酸酶（ALP活性、ALP阳性克隆数（colonies stained positive for alkaline phosphatase，CFU-F_ALP、骨钙素分泌量、钙盐沉积量以及钙化结节数量的差异，Real Time RT-PCR法检测IGF-1、Osterix和Runx-2的基因表达情况。Western-blot法检测Ⅰ型胶原蛋白的分泌量。结果 淫羊藿素可显著增强rBMSCs的ALP活性，促进钙盐沉积和骨钙素的分泌，增加CFU-F_ALP和钙化结节数量，提高IGF-1、Osterix和Runx-2的mRNA水平，同时也可增强Ⅰ型胶原蛋白的分泌，而脱水淫羊藿素并未表现出类似效应。结论 淫羊藿素促进rBMSCs成骨性分化的活性显著高于脱水淫羊藿素，可能是二者异戊烷链上的构型差异，导致淫羊藿素的生物活性强于脱水淫羊藿素，提示我们可以通过对药物进行化学结构的改造，增强药效，降低毒性，从而研究开发出新型抗骨质疏松药物。

Comparative Study on the Effects of the Osteogenic Differentiation of Rat Bone Marrow Stromal Cells by Icaritin and Dehydrated Icaritin

OBJECTIVE To investigate the effects of icaritin and dehydrated icaritin on the osteogenic differentiation of rat bone marrow stromal cells (rBMSCs. METHODS rBMSCs were cultured by adherence screening method. Icaritin and dehydrated icaritin were supplemented into the culture at 1×10-5 mol·L-1， respectively. The osteogenic differentiation markers including alkaline phosphatase (ALP activity, CFU-F_ALP, osteocalcin secretion, calcium deposition and mineralized bone modulus were compared among the icaritin, dehydrated icaritin and the control groups. The gene expressions of IGF-1, Osterix and Runx-2 were examined by Real Time RT-PCR. Total protein also was isolated， and the secretion of collagenⅠwas examined by Western-blot. RESULTS Icaritin improved ALP activity, CFU-F_ALP amount, osteocalcin secretion, calcium deposition and mineralized modulus significantly. Besides, they enhanced the gene expression of IGF-1, Osterix and Runx-2. The secretion of collagenⅠalso was promoted by Icaritin .But these effects could not be detected in dehydrated icaritin group. CONCLUSION Icaritin is stronger than dehydrated icaritin at enhancing the osteogenic differentiation of rBMSCs. It is suggested that the difference of configuration between icaritin and dehydrated icaritin lead to the stronger bioactivity of the former chemical. So, we can develop new drugs for antiosteoporosis through reforming the structures of drugs, to enhance the effects while decrease the toxicity.