丙泊酚调节CREB介导的自噬对缺血性脑损伤保护作用的研究

Intravenous anesthetic propofol is considered to be a neuroprotective agent. Our recent study found that inhibition of pCREB dephosphorylation in the peri-infarct region of ischemic mice cerebral cortex is involved in propofol neuroprotection. However, the exact neuroprotective mechanism of propofol modulating pCREB level remains unclear. The recent research have demonstrated that autophagy is involved the neuroprotection of propofol and show controversial character in ischemia-hypoxia：aggravate or relieve injury and signaling proteins related CREB are involved in regulating autophagy. This project will carry out behavioral study, morphology, molecular biology and molecular cloning techniques on the rat MCAO, cell hypoxia models to detect CREB phosphorylation level regulated by upstream kinases related autophagy Akt，GSK3β，mTOR，p70S6K; to explore the role of Bcl-2 modulating by CREB phosphorylation in autophagy and propofol neuroprotection; to clarify the molecular mechanism of propofol neuroprotection modulating mediated by CREB. Our study will help to clarify the neuroprotection and molecular mechanism of propofol and provide the scientific basis to treat of cerebral ischemia injury.

)：静脉麻醉药丙泊酚具有一定的脑保护作用。我们前期的研究结果提示，丙泊酚可通过抑制小鼠缺血皮层半影区pCREB的去磷酸化产生脑保护作用，但其调节pCREB 水平产生脑保护作用的机制尚不明确。文献报道，丙泊酚的脑保护作用与调节自噬有关，自噬在缺血性脑损伤中表现出减轻和加重损伤的双重特性，CREB相关信号蛋白参与自噬的调节。本课题在前期工作的基础上利用小鼠大脑中动脉栓塞、细胞低氧模型，借助行为学、形态学、分子生物学和分子克隆等技术，检测CREB上游自噬相关蛋白激酶Akt，mTOR，p70S6K ，GSK3β对CREB磷酸化水平的调节，探讨CREB磷酸化调控靶基因Bcl-2在自噬及丙泊酚脑保护中的作用，以明确丙泊酚调节CREB介导的自噬产生脑保护作用的分子机制。所获成果将丰富人们对丙泊酚脑保护作用及分子机制的认识，为临床治疗缺血性脑病提供科学依据。

明确了丙泊酚是通过抑制自噬产生脑保护作用。并且随着丙泊酚浓度的增高这种抑制作用加强。丙泊酚处理原代培养小鼠海马细胞的1908种microRNA中，40种microRNAs含量发生2倍上调，有54种microRNAs含量2倍下调。丙泊酚通过下调miR-297a-5p上调Bcl-2，上调miR-6983-5p下调p53产生脑保护作用。