七氟醚通过海马PICK1/ERK1/2/GSK3β信号抑制记忆巩固的研究

Research on Sevoflurane Inhibits Hippocampal Memory Consolidation Through PICK1/ERK1/2/GSK3β Signaling

关键词:  七氟醚  记忆巩固  PICK1  ERK1/2  GSK3β

Key words:  sevoflurane  memory consolidation  PICK1  ERK1/2  GSK3β

摘要:

目的 研究七氟醚对记忆巩固的影响，并探讨PICK1/ERK1/2/GSK3β信号通路在其中的作用。方法 采用C57BL/6J PICK1基因敲除小鼠进行七氟醚处理（2%，3 h），提取动物海马组织蛋白，采用Western blot检测PICK1、ERK1/2、p-ERK1/2、GSK3β及p-GSK3β蛋白表达变化。采用原代海马神经细胞，加入ERK1/2磷酸化激动剂Honokiol和/或PICK1抑制剂FSC231，再进行七氟醚处理（2%，3 h），检测p-GSK3b蛋白表达变化。通过旷场试验检测动物运动能力变化，抑制性逃避试验检测动物记忆巩固的变化。结果 在体实验中，单独进行七氟醚处理或敲除PICK1基因均可明显降低PICK1、p-ERK1/2及p-GSK3β的蛋白表达水平。与七氟醚组相比，PICK1基因敲除+七氟醚处理组，p-ERK1/2及p-GSK3β的蛋白表达水平进一步降低。离体实验中，七氟醚可降低p-GSK3β蛋白表达水平，加入Honokiol可使p-GSK3β蛋白表达增加，而再加入FSC231则可逆转由Honokiol引起的p-GSK3β蛋白变化。行为学结果显示，七氟醚处理或PICK1基因敲除动物运动能力无明显变化，而七氟醚可抑制记忆巩固；PICK1基因敲除小鼠进行七氟醚处理，则可加重抑制记忆巩固。结论 七氟醚可抑制记忆巩固过程，其机制可能与PICK1/ERK1/2/GSK3β信号通路受抑制相关。

Abstract:

OBJECTIVE To study the effects of sevoflurane on memory consolidation, and the role of PICK1/ERK1/2/GSK3β signaling pathway. METHODS C57BL/6J PICK1 knock-out mice were exposed to 2% sevoflurane for 3 h. The hippocampal tissues were collected for detecting the protein expressions of PICK1, ERK1/2, P-ERK1/2, GSK3β and P-GSK3β by Western blot. Primary hippocampal neurons were treated with phospho-ERK1/2 activator Honokiol or/and PICK1 inhibitor FSC231 before sevoflurane(2%, 3 h) exposure. Neurons were harvested for detection of p-GSK3β protein level. The open-field test and inhibitory avoidance task were enrolled for evaluation of motor activity and memory consolidation respectively. RESULTS The protein levels of PICK1, p-ERK1/2 and p-GSK3β were depressed in sevoflurane or PICK1 knock-out group. Compared with sevoflurane group, the expressions of p-ERK1/2 and p-GSK3β were further decreased in sevoflurane plus PICK1 knock-out group. The expression of p-GSK3β was inhibited by sevoflurane exposure, which could be improved by application of Honokiol. Moreover, the improvement of p-GSK3β by Honokiol could be reversed by further addition of FSC231. Finally, analysis of behaviour study showed that sevoflurane treatment or PICK1 knock-out did not alter the motor activity. However, sevoflurane administration inhibited memory consolidation. For the knock-out mice, the memory consolidation was further suppressed by sevoflurane exposure. CONCLUSION Sevoflurane can inhibit the memory consolidation process, and the mechanism may be related to inhibition of the PICK1/ERK1/2/GSK3β signaling pathway.