Wang Li, Liu Yuan, Li Sen, Long Zai-Yun, Wu Ya-Min
The 3rd Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury Chongqing 400042, PR China.
Int J Clin Exp Pathol. 2015 Jan 1;8(1):578-85. eCollection 2015.
Neural stem cells (NSCs) are multipotent cells that have the capacity for differentiation into the major cell types of the nervous system, i.e. neurons, astrocytes and oligodendrocytes. Valproic acid (VPA) is a widely prescribed drug for seizures and bipolar disorder in clinic. Previously, a number of researches have been shown that VPA has differential effects on growth, proliferation and differentiation in many types of cells. However, whether VPA can induce NSCs from embryonic cerebral cortex differentiate into neurons and its possible molecular mechanism is also not clear. Wnt signaling is implicated in the control of cell growth and differentiation during CNS development in animal model, but its action at the cellular level has been poorly understood. In this experiment, we examined neuronal differentiation of NSCs induced by VPA culture media using vitro immunochemistry assay. The neuronal differentiation of NSCs was examined after treated with 0.75 mM VPA for three, seven and ten days. RT-PCR assay was employed to examine the level of Wnt-3α and β-catenin. The results indicated that there were more β-tublin III positive cells in NSCs treated with VPA medium compared to the control group. The expression of Wnt-3α and β-catenin in NSCs treated with VPA medium was significantly greater compared to that of control media. In conclusion, these findings indicated that VPA could induce neuronal differentiation of NSCs by activating Wnt signal pathway.
神经干细胞（NSCs）是多能细胞，具有分化为神经系统主要细胞类型的能力，即神经元、星形胶质细胞和少突胶质细胞。丙戊酸（VPA）是临床上广泛用于治疗癫痫和双相情感障碍的药物。此前，许多研究表明VPA对多种细胞的生长、增殖和分化有不同影响。然而，VPA是否能诱导胚胎大脑皮质的神经干细胞分化为神经元及其可能的分子机制也尚不清楚。在动物模型中，Wnt信号通路参与中枢神经系统发育过程中的细胞生长和分化控制，但其在细胞水平的作用尚未得到充分了解。在本实验中，我们使用体外免疫化学分析法检测了VPA培养基诱导的神经干细胞的神经元分化。用0.75 mM VPA处理神经干细胞三天、七天和十天后，检测其神经元分化情况。采用逆转录聚合酶链反应（RT-PCR）分析法检测Wnt-3α和β-连环蛋白的水平。结果表明，与对照组相比，用VPA培养基处理的神经干细胞中β-微管蛋白III阳性细胞更多。与对照培养基相比，用VPA培养基处理的神经干细胞中Wnt-3α和β-连环蛋白的表达明显更高。总之，这些发现表明VPA可通过激活Wnt信号通路诱导神经干细胞的神经元分化。
