Mir124介导柴胡疏肝散调控抑郁症肝郁证模型海马神经可塑性的分子机制研究

Depression is a mood disorder most commonly，and hippocampal neuronal plasticity disorder is the key pathogenesis of depression. Numerous studies have shown that chronic stress effects of CREB phosphorylation through ERK-MAPK signaling pathways, further regulation of BDNF gene expression and the neuronal synaptic plasticity, which is one of the important mechanisms of depresion. Our previous studies found that Expression of miR-124 in the hippocampus was significantly increased in chronic stress depresssion rat with liver-Qi stagnation syndrome. Therefore, we hypothesized that chronic stress may modulate the expression of Mir124, and effected the activation of CREB through the ERK-MAPK pathway , further regulated the expression of targwet gene, and cause hippocampal neuronal plasticity impairment, thereby Leading to the formation of depression with liver-Qi stagnation syndrome. In order to further explore the specific mechanism of Mir124 regulation of hippocampal neuronal plasticity of depression with liver-Qi stagnation syndrome. This research plans to select the rat model of depression with liver-qi stagnation syndrome, we will observe the hippocampal neurogenesis, survival, proliferation and synaptic ultrastructure, and test the expression of Mir124 and some Cell factor of ERK-MAPK-CREB signal pathway in hippocampcus, analysis of the correlation between the Mir124 and signal pathway; And we will also study the mechanism of Mir124 effect on the hippocampal neurons at the cellular level . Simultaneous we will observe the effection and mechanism of Prescription Chaihu Shugan on this pathway, in order to explore the mechanism of depression with Liver-qi stagnation syndrome and new target for anti depression medicine.

抑郁症是最常见的心境障碍，海马神经可塑性障碍是其关键病机，但具体调控机制尚不清楚。研究显示慢性应激经ERK-MAPK通路影响CREB磷酸化导致神经可塑性障碍在抑郁症发病中起着重要作用。申请者前期研究发现Mir124在慢性应激抑郁症肝郁证大鼠海马内明显上调。我们推测慢性应激通过上调mir124表达，经ERK-MAPK通路影响CREB活化,损害海马神经可塑性，是抑郁症肝郁证形成的一个关键机制。为了进一步探索Mir124 调控抑郁症肝郁证海马神经可塑性的具体作用机制。本研究拟选用抑郁症肝郁证大鼠模型，观察海马神经形态和超微结构, 检测海马mir124表达并分析其与ERK-MAPK-CREB通路之间的关联；进一步在细胞水平调控mir124表达，观察其对海马神经元的影响及作用机制；同时以方测证，观察疏肝解郁中药方柴胡疏肝散对此通路的干预作用及机制，以探索抑郁症肝郁证的形成机制及中药抗抑郁的新靶点。

抑郁症是一种高复发、高致残、高致死的常见心理疾病。然而，抑郁症是多病因疾病，目前尚未能完全阐释其发病机理。目前公认的理论为海马神经元可塑性障碍是抑郁症的病机关键，是其发病的病理生理学基础，但海马神经可塑性障碍的具体调控机制以及抗抑郁药对其作用机制尚不十分清楚。近年来多个研究显示miRNA直接或间接与抑郁症的发生、发展及治疗相关联,为抑郁症发病机制研究提供了新的方向。再者，从中医角度出发，抑郁症属中医“郁病”范畴, 与中医肝脏的疏泄功能,特别与情志内郁导致肝失疏泄、气机郁滞病机关系密切。中医认为肝郁是抑郁症发病的基本病机，中医治疗郁病多采用疏肝解郁法。所以，本研究选用孤养模型加慢性不可预见应激来复制抑郁症肝郁证模型，评价抑郁行为学指标，观察大鼠海马神经发生、神经元生存、增殖及突触超微结构改变, 然后检测海马内mir124 的表达水平和相关信号通路的关键细胞因子水平，并分析它们之间的关联；在此基础上，进一步在细胞水平调控mir124 表达，分析疏肝解郁中药方柴胡疏肝散对相关通路的干预作用及机制，以探索抑郁症肝郁证的形成机制和证候本质。. 本研究成功复制抑郁症动物模型，并观察海马神经元的变化，探索抑郁症海马内的微观变化，初步明确了抑郁症的关键病理变化和病机，发现柴胡疏肝散可以通过下调mir124缓解抑郁症状，且有可能是通过上调MAPK14和GRia3蛋白，从而影响海马神经元可塑性。同时本研究还通过iTRAQ –LC-MS/MS筛查到一些柴胡疏肝散调控mir124相关的特异性蛋白，并进行了Go分析、ＫＥＧＧ和ＰＰＩ分析，找到柴胡疏肝散干预相关的系列蛋白和通路。