荭草苷抑制PERK/ATF4/CHOP通路改善癫痫小鼠认知功能障碍机制

Mechanism of Orientin in improving cognitive impairment in epileptic mice by inhibiting PERK/ATF4/CHOP pathway

目的探索荭草苷抑制PERK/ATF4/CHOP通路改善癫痫小鼠认知功能障碍的机制。方法腹腔注射东莨菪碱与盐酸匹鲁卡品,建立癫痫小鼠模型。小鼠随机分为5组:对照组、模型组、荭草苷(50 mg/kg)组、MK-28(PERK激活剂,1 mg/kg)组、荭草苷(50 mg/kg)+MK-28(1 mg/kg)组,分组给药后,观察小鼠癫痫发作情况;Morris水迷宫检测认知功能;TUNEL染色检测海马神经元凋亡率;ELISA测量血清COX-2、IL-18及IL-6水平;免疫印迹法检测海马组织凋亡及PERK/ATF4/CHOP通路蛋白表达。结果荭草苷组小鼠发作次数及持续时间、逃避潜伏期、海马神经元凋亡率、血清COX-2、IL-18及IL-6水平、海马组织Caspase-3、Bax、ATF4、CHOP蛋白表达及p-PERK/PERK相比模型组和荭草苷+MK-28组均降低(P<0.05),MK-28组小鼠各指标变化趋势与荭草苷组相反。结论荭草苷可通过抑制PERK/ATF4/CHOP通路激活阻止炎症,减轻癫痫小鼠海马神经元凋亡,改善其认知功能。

Objective To explore the mechanism of orientin in improving cognitive impairment in epileptic mice by inhibiting PERK/ATF4/CHOP pathway.Methods The epilepsy mouse model was established by intraperitoneal injection of scopolamine and pilocarpine hydrochloride.The mice were randomly divided into five groups:control group,model group,orientin(50 mg/kg)group,MK-28(PERK activator,1 mg/kg)group,orientin(50 mg/kg)+MK-28(1 mg/kg)group.After grouping,the epileptic seizures of the mice were observed.Morris water maze test was used to detect the cognitive function of mice.TUNEL staining was used to detect the apoptosis rates of hippocampal neurons of mice.ELISA was used to measure the levels of serum COX-2,IL-18 and IL-6 of mice.Western blotting was used to detect the expression of apoptosis and PERK/ATF4/CHOP pathway protein in the hippocampus of mice.Results The number and duration of attacks per day,escape latency,hippocampal neuronal apoptosis rate,serum COX-2,IL-18 and IL-6 levels,and hippocampal tissue caspase-3,Bax,ATF4,CHOP protein expression and p-PERK/PERK in the orientin group were lower than those in the model group and the orientin+MK-28 group(P<0.05),the change trend of each index in MK-28 group was opposite to that in orientin group.Conclusions Orientin can inhibit the activation of the PERK/ATF4/CHOP pathway to prevent inflammation,reduce the apoptosis of hippocampal neurons in epileptic mice and improve their cognitive function.