关于WNK3-SPAK/OSR1-NKCC1信号通路在脑梗死中作用机制的体内外研究

研究表明，脑缺血会诱导钠-钾-氯共转运体1（NKCC1）的活化，从而导致细胞内钠离子超载，细胞毒性水肿及神经元的坏死和凋亡。然而，脑梗死中NKCC1活化的潜在分子机制仍不明确。WNK激酶可以通过下游底物SPAK/OSR1，磷酸化NKCC1，从而使其活化。但是，WNK-SPAK/OSR1信号通路是如何调控脑梗死中NKCC1活化的机制，目前还不清楚。本课题将首次探讨：1.WNK3-SPAK/OSR1级联反应是如何调节脑缺血后NKCC1的表达和降解；敲减/敲除WNK3-SPAK/OSR1信号通路基因是否对脑梗死有神经保护作用。2.触发脑缺血后神经元WNK3-SPAK/OSR1-NKCC1级联反应的因素。本研究首次对WNK3-SPAK/OSR1-NKCC1信号通路在脑梗死中的作用机制进行研究，将为在分子水平上寻求脑梗死治疗的新靶点提供理论。

Ischemia-induced stimulation of Na+-K+-Cl- cotransporter (NKCC1) has been demonstrated to cellular Na+ overload, cytotoxic edema, and necrotic and apoptotic cell death. WNK kinases regulate NKCC1 by directly phosphorylating, via SPAK and OSR1, two down-stream substrates of WNK kinases. However, it remains unknown whether or how the WNK-SPAK/OSR1 signaling pathway governs NKCC1 activation in ischemic brains. .We will conduct the following experiments to investigate the underlying mechanisms. 1. To investigate how the WNK3-SPAK/OSR1 cascade regulates NKCC1 expression and degradation after ischemia? Whether knockdown of this signaling pathway accounts for the neuroprotective effects against ischemia? 2. Identify factors which trigger the stimulation of the WNK-SPAK/OSR1-NKCC1 cascade in neurons after ischemia. Our initial investigation of the WNK3-SPAK/OSR1-NKCC1 signaling cascade in ischemic damage is a foundation for future testing of novel WNK pathway inhibitors for stroke therapy.