葛根素干预激素诱导骨髓间充质干细胞成脂分化的Wnt信号途径

背景：国内外学者研究证明，激素性股骨头缺血性坏死的发病机制与体内脂质代谢紊乱，尤其是大剂量激素诱导下骨髓间充质干细胞的成脂分化有关。目前葛根素抑制激素诱导骨髓间充质干细胞成脂分化的Wnt信号转导途径还未经证实。〈br〉 目的：观察葛根素干预激素诱导大鼠骨髓间充质干细胞成脂分化过程中 Wnt 信号途径相关基因及关键蛋白β-catenin表达的变化。〈br〉 方法：第3代SD大鼠骨髓间充质干细胞随机分为空白组、激素组、葛根素低、中、高剂量组，5组干预6 d后RT-PCR法检测Wnt/β-catenin信号通路主要成员Wnt10b mRNA、GSK3β mRNA、β-catenin mRNA的表达，Western blot法对β-catenin蛋白的表达进行检测分析。〈br〉 结果与结论：与激素组比较，葛根素各干预组Wnt10b mRNA、β-catenin mRNA及β-catenin蛋白的表达水平均显著升高；GSK3βmRNA的表达水平显著降低。提示葛根素对激素诱导骨髓间充质干细胞成脂分化的抑制作用可能是通过调节信号通路的Wnt10b mRNA、GSK3βmRNA、β-catenin mRNA及β-catenin蛋白的表达来实现的。葛根素防治激素性股骨头缺血坏死的机制不仅是改善股骨头局部的微循环，同时还与其抑制激素诱导下骨髓间充质干细胞的成脂分化有关。

Wnt signaling pathway by which puerarin suppresses adipogenic differentiation of glucocorticoid-induced bone marrow mesenchymal stem cells

BACKGROUND：Recently, glucocorticoid-induced necrosis of femoral head has been much studied. However, the precise Wnt signaling pathway by which puerarin suppresses adipogenic differentiation of glucocorticoid-induced bone marrow mesenchymal stem cells adipogenic differentiation of glucocorticoid-induced bone marrow mesenchymal stem cells remains unconfirmed. OBJECTIVE：To investigate the expression of Wnt signaling pathway related genes and the key factor protein,β-catenin, during adipogenic differentiation of glucocorticoid-induced rat bone marrow mesenchymal stem cells treated by puerarin. METHODS：The third generation of bone marrow mesenchymal stem cells were cultured with Dulbecco’s modified Eagle’s medium containing blank serum （blank control group）, dexamethasone （hormone group）, dexamethasone with puerarin low dose group, the middle dose group and high dose group. After 6 days of culture, in the above five groups, the expressions of Wnt/β-catenin signaling pathway members, Wnt10b mRNA, GSK3βmRNA,β-catenin mRNA, were detected using RT-PCR assay, and the expression ofβ-catenin protein was detected using western blot assay. 〈br〉 RESULTS AND CONCLUSION：Compared with the control group, the Wnt10b mRNA,β-catenin mRNA andβ-catenin protein expressions were significantly higher in puerarin groups, but GSK3βmRNA expression was significantly lower in the puerarin groups. These findings suggest that puerarin effects on inhibition of adipogenic differentiation of glucocorticoid-induced bone marrow mesenchymal stem cells probably are realized through the activation of Wnt/β-catenin signal pathway and regulation of the key factor Wnt10b mRNA, GSK3βmRNA,β-catenin mRNA, andβ-catenin protein expressions. The mechanism by which puerarin prevents glucocorticoid-induced necrosis of femoral head not only improves local microcirculation of the femoral head, but also relates to its inhibitory effects on adipogenic differentiation of glucocorticoid-induced bone marrow mesenchymal stem cells.