抑郁模型大鼠海马突触的差异蛋白质组学分析

Differential Proteomics Analysis of Hippocampal Synaptic Proteins in Rat Depression Model

目的通过抑郁模型大鼠海马突触的差异蛋白质组学分析,为抑郁症发病机制研究提供依据。方法根据糖水消耗基线值将40只健康雄性Sprague-Dawley大鼠随机分为慢性轻度不可预见性应激组和对照组(每组20只) 通过CUMS实验模式建立大鼠抑郁模型后,运用蔗糖密度梯度离心法提取两组大鼠的海马突触并用透射电镜进行检测。采用传统的双向凝胶电泳和基质辅助激光解析电离飞行时间串联质谱进行差异蛋白质组学分析。结果在行为学评价中CUMS组大鼠糖水消耗量和偏好度均降低(P<0.01),表明大鼠抑郁模型建立成功。通过结合双向凝胶电泳和质谱分析,共得到6个在CUMS组表达上调和10个在CUMS组表达下调的蛋白质,这些蛋白质的功能主要归为四类,即囊泡调节/递质释放/信号转导、能量代谢、细胞骨架、物质代谢。结论通过对抑郁模型大鼠海马突触的比较蛋白质组学分析及后续的蛋白质功能预测,发现了一些与突触传导功能障碍可能相关的蛋白质,从而为抑郁症发病机制的研究提供了有价值的线索。

Objective In order to provide clues for studies on the pathogenesis of depression, the differential proteomics of hippocampal synaptic proteins in a rat depression model was analyzed. Methods According to the baseline of sucrose consumption ,40 male Sprague-Dawley rats were divided into Chronic Unpredictable Mild Stress （CUMS） and control groups randomly （ n = 20 per group）. After establishment of rat de- pression model via CUMS experimental mode ,rat hippocampal synapses from the two groups were prepared by discontinuous sucrose density gradient centrifugation and detected by transmission electron microscope. Subsequently, the differential proteomics analysis were performed by conventional two-dimensional gel electrophoresis （2DE） and matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrom- etry （MALDI-TOF/TOF-MS）. Results The experimental results from the sucrose consumption test showed consistent decreases of sucrose in- take and preference in the CUMS group （ P 〈 0. 01 ）, suggesting that the rat depression model had been successfully established. By 2DE combined with mass spectrometry analysis （2DE-MS）,6 up-regulated and 10 down-regulated proteins in the CUMS group compared with those in the control group were discovered. These proteins were mainly classified into four functional categories including vesicle regulation/ ncurotransmitter release/signal transduction, energy metabolism, cytoskeleton and substance metabolism. Conclusions By the comparative proteomics analysis and subsequent protein function prediction, we revealed some differentially expressed proteins related with hippocampal synaptic conduction obstacles in depression-model rats, thereby providing valuable clues for studies on the pathogenesis of depression.