骨碎补总黄酮依赖PI3K/Akt通路与牙髓干细胞的成骨分化

背景：PI3K/Akt通路可能在骨碎补总黄酮促成骨分化作用中发挥重要调控作用。 目的：观察骨碎补总黄酮对大鼠牙髓干细胞成骨分化的影响,并对PI3K/Akt通路在其中的作用进行初步探讨。 方法：采用组织块消化法获得大鼠牙髓细胞,克隆化分离培养大鼠牙髓干细胞并进行鉴定。在培养体系中加入不同质量浓度(0.01,0.05,0.1 g/L)的骨碎补总黄酮,观察各组细胞的碱性磷酸酶水平及钙结节形成情况,并用Western Blot法检测各组细胞磷酸化Akt的表达变化。 结果与结论：分离得到的牙髓干细胞的细胞表面标志CD44和CD29呈阳性表达,而CD34表达呈阴性。骨碎补总黄酮组牙髓干细胞的碱性磷酸酶活性、钙结节形成能力和磷酸化Akt蛋白相对表达量增加,较空白对照组差异有显著性意义,且随骨碎补总黄酮质量浓度的增加而升高,表现出一定浓度和时间依赖性。说明骨碎补总黄酮对大鼠牙髓干细胞成骨分化具有促进作用,且该作用可能是依赖PI3K/Akt通路所介导的。

Effects of drynaria total flavonoid on osteogenic differentiation of rat dental pulp stem cells via PI3K/Akt pathway

BACKGROUND:PI3K/Akt pathway may play an important regulative role in osteogenic differentiation of dental pulp stem cells induced by drynaria total flavonoid.   OBJECTIVE:To explore the effects of total flavonoids of drynaria on osteogenic differentiation of rat dental pulp stem cells and investigate the role of PI3K/Akt pathway in the induced differentiation of rat dental pulp stem cells. METHODS:Rat dental pulp stem cells were harvested by enzymatic digestion, cultured and identified by immunohistochemical staining. The dental pulp stem cells were cultured in media with different concentrations of drynaria total flavonoid (0.01 g/L, 0.05 g/L and 0.1 g/L). Alkaline phosphatase activities and formation of calcified tubercles in cells were determined in each group. Phosphorylated Akt expression in cells was detected by western blot method in each group. RESULTS AND CONCLUSION:Dental pulp stem cells were positive for CD44 and CD29 expression, but they were negative for CD34. Compared to the blank control group, alkaline phosphatase activities, formation of calcified tubercles and phosphorylated Akt expression were significantly increased in the drynaria total flavonoid group in a dose- and time-dependent manner. These findings suggest that drynaria total flavonoid can promote the osteogenic differentiation of rat dental pulp stem cells, and this effect is likely mediated by PI3K/Akt pathway.