目的:探索睡眠剥夺(sleep deprivation, SD)后大鼠认知功能改变与磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinase, PI3K) /蛋白激酶B(protein kinase B, AKT)/哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin, mTOR)信号通路的相关性,为后续探讨失眠的发病机制提供参考依据。方法:选取8周龄SD大鼠20只作为研究对象,适应性喂养1周后,随机分为对照组和慢性睡眠剥夺组(实验组)各10只,采取改良多平台水环境法进行睡眠剥夺。通过莫里斯水迷宫检测所有大鼠的认知功能,采用蛋白质免疫印迹分析检测海马组织中P-PI3K、P-Akt、P-mTOR、自噬相关蛋白Beclin-1、半胱氨酸天冬氨酸蛋白酶-3(cysteine-aspartic acid protease-3, Caspase-3)蛋白表达情况。结果:与对照组相比,实验组大鼠第5天逃避潜伏期明显延长(P＜0.01)、通过平台次数减少(P＜0.05)、目标象限停留的时间减少(P＜0.05);大鼠海马区P-PI3K、P-Akt、P-mTOR蛋白表达明显降低(P＜0.01),Beclin-1表达增加(P＜0.01),凋亡相关蛋白Caspase表达增加(P＜0.01),差异均有统计学意义。结论:(1)大鼠睡眠剥夺7 d后海马组织中通路蛋白P-PI3K、P-Akt、P-mTOR表达量较正常大鼠减少,空间学习、记忆能力降低,推测大鼠慢性睡眠剥夺后认知功能损伤可能与PI3K/Akt/mTOR信号通路受抑制有关;(2)大鼠睡眠剥夺7 d后海马组织中的自噬相关蛋白Beclin 1、凋亡蛋白Caspase-3表达量,较正常大鼠增加。
Objective: To explore the correlation between the changes of cognitive function and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway in rats after sleep deprivation (SD), and to provide a reference for the subsequent exploration of the pathogenesis of insomnia. Methods: The 8-week-old SD rats were used as the research object. After 1 week of adaptive feeding, they were randomly divided into 2 groups, with 10 rats in each group. The control group and the chronic sleep deprivation group (experimental group) were subjected to sleep deprivation by modified multi-platform water environment method. Morris water maze was used to detect the cognitive function of all rats. Western blot analysis was used to detect the expression of P-PI3K, P-Akt, P-mTOR, Beclin-1 and Caspase-3 protein in hippocampus. Results: Compared with the control group, the escape latency on the fifth day of the experimental group was significantly prolonged (P＜0.01), the number of times through the platform was reduced (P＜0.05), and the time spent in the target quadrant was reduced (P＜0.05). The expression of P-PI3 K, P-Akt and P-mTOR protein in hippocampus of rats was significantly decreased (P＜0.01), the expression of autophagy-related protein Beclin-1 was increased (P＜0.01), and the expression of apoptosis-related protein Caspase was increased (P＜0.01), the difference was statistically significant. Conclusion: (1)The expression of P-PI3K、P-Akt and P-mTOR in hippocampus of rats after 7 days of sleep deprivation is lower than that of normal rats, and the ability of spatial learning and memory is decreased. It is speculated that the cognitive impairment after chronic sleep deprivation in rats may be related to the inhibition of PI3K/Akt/mTOR signaling pathway; (2)The expression of autophagy-related protein Beclin-1 and apoptotic protein Caspase-3 in hippocampus of rats after 7 days of sleep deprivation is higher than that of normal rats.
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