目的:为了研究EerdunWurile(EW)的作用,一种传统的蒙古药,在术后认知功能障碍(POCD)动物模型中,通过激活IRS-PI3K-AKT-GLUT4通路对大鼠认知功能的影响。
方法:将50只清洁级成年SpragueDawley(SD)雄性大鼠分为五组之一:(1)无麻醉的对照组(C组),(2)POCD模子组仅麻醉(P组),(3)POCD组采用低剂量EW治疗(L组),(4)POCD组采用高剂量EW治疗(H组),(5)POCD模型组,右美托咪定治疗(D组)为阳性对照。研究在所有大鼠适应饲养后7天开始。手术前5天在Morris水迷宫导航中训练大鼠。所有大鼠在术前第1天和术后第1、3、5天进行相同的迷宫导航和空间探索实验,并评估其学习记忆能力。在水迷宫实验结束时,处死大鼠,获得海马组织。IRS-2、PI3K、AKT,通过实时PCR在海马中测量GLUT4,和IRS-2,PI3K的表达,AKT,通过蛋白质印迹法测定海马中的GLUT4蛋白,以在分子水平上研究潜在的机制。
结果:与对照组C相比,P组,L,H,术后1、3和5天,D显示逃避潜伏期延长(P<0.05),穿越平台次数减少(P<0.05)。与P组相比,L组,H,和D在手术后的所有时间点显示逃避潜伏期减少,穿越平台的次数增加(P<0.05)。在个人P中,L,H,D组,与术后1天相比,术后3天至5天,逃避潜伏期减少(P<0.05),平台交叉次数增加(P<0.05)。与C组相比,IRS-2、PI3K、P海马中的AKT和GLUT4,L,H,与D组相比,差异有统计学意义(P<0.05)。与P组相比,IRS-2,PI3K,AKT,和L海马中的GLUT4,H,与D组相比,差异有统计学意义(P<0.05)。与D组相比,L组和H组IRS-2和AKT的表达水平均较高。L组PI3K的表达水平也高于D组(P<0.05)。H组AKTmRNA的表达高于L组(P<0.05)。与C组相比,P组海马p-IRS-2/IRS-2比值高于C组(P<0.05)。与P组相比,L组中p-IRS-2/IRS-2的比率,H组,D组较低,和p-PI3K/PI3K的比值,p-AKT/AKT,p-GLUT4/GLUT4较高(P<0.05)。
结论:给予EW对POCD大鼠的信号通路有影响。低剂量组疗效较好。这可能与胰岛素下游信号分子PI3K和IRS-PI3K-AKT-GLUT4信号通路有关。
OBJECTIVE: To study the effect of Eerdun Wurile (EW), a traditional Mongolian medicine, on the cognitive function of rats by activating the IRS-PI3K-AKT-GLUT4 pathway in an animal model of postoperative cognitive dysfunction (POCD).
METHODS: Fifty clean-grade adults Sprague Dawley (SD) male rats were assigned to one of five groups: (1) a control group with no anesthesia (Group C), (2) a POCD model group with anesthesia only (Group P), (3) POCD group with low-dose EW treated (Group L), (4) a POCD group with high-dose EW treated (Group H), and (5) a POCD model group with dexmedetomidine treated (Group D) for positive control. The study started 7 days after all rats had acclimated to housing. Rats were trained in the Morris Water Maze navigation 5 days before surgery. All rats underwent the same maze for navigation and spatial exploration experiments on the preoperative day 1 and postoperative days 1, 3, 5, and their learning and memory abilities were assessed. At the end of the water maze experiment, rats were sacrificed to obtain hippocampal tissue. The mRNA levels of IRS-2, PI3K, AKT, and GLUT4 were measured in the hippocampus by real-time PCR, and the expression of IRS-2, PI3K, AKT, and GLUT4 protein in the hippocampus was determined by Western blotting to investigate the potential mechanisms at the molecular level.
RESULTS: Compared to control Group C, Group P, L, H, and D showed prolonged escape latency (P < 0.05) and decreased number of times to cross the platform (P < 0.05) at 1, 3 and 5 days after surgery. Compared to Group P, Group L, H, and D showed a decrease in escape latency with an increased number of crossing the platform at all-time points after surgery (P < 0.05). Within individual P, L, H, and D groups, escape latencies decreased (P < 0.05) and the number of times that the platform was crossed increased (P < 0.05) between postoperative days 3 and 5 compared to postoperative 1 day. Compared to Group C, the mRNA expression of IRS-2, PI3K, AKT and GLUT4 in the hippocampus of P, L, H, and D groups were decreased (P < 0.05). Compared to Group P, IRS-2, PI3K, AKT, and GLUT4 in the hippocampus of L, H, and D groups were increased (P < 0.05). Compared with Group D, the expression levels of IRS-2 and AKT in both L and H groups were higher. The expression level of PI3K in Group L was also higher (P < 0.05) vs Group D. The expression of AKT mRNA in Group H was higher than in Group L (P < 0.05). Compared to Group C, the p-IRS-2/IRS-2 ratio in the hippocampus of Group P was higher than that of Group C (P < 0.05). Compared to Group P, the ratios of p-IRS-2/IRS-2 in Group L, Group H, and Group D were lower, and the ratios of the p-PI3K/PI3K, p-AKT/AKT, and p-GLUT4/GLUT4 were higher (P < 0.05).
CONCLUSIONS: Administration of EW showed the effect on the signaling pathway in rats with POCD. The therapeutic effect was better in the low-dose group. This could be related to the insulin downstream signal molecule PI3K and the IRS-PI3K-AKT-GLUT4 signaling pathway.