PIP对缺血性脑卒中大鼠皮质和海马Atg5、Atg14自噬蛋白以及神经功能的影响

Effects of Piperine on Atg5、Atg14 Autophagy Proteins in Cortical and Hippocampal and Neural Function of Ischemic Stroke Rats

目的 探讨不同浓度胡椒碱(piperine,PIP)对缺血性脑卒中大鼠皮质和海马自噬相关基因(autophagyrelated gene)Atg5、Atg14自噬蛋白以及神经功能的影响。方法 建立永久性大脑中动脉闭塞(permanent middle cerebral artery occlusion,pMCAO)体内模型,通过每天灌胃一次的干预方式证实PIP对缺血性脑卒中大鼠皮质和海马Atg5、Atg14自噬蛋白以及神经功能的影响。实验分为假手术组、模型组、10、20、30 mg·kg^(-1)PIP干预组,共五组。TTC染色法检测大鼠大脑梗死面积;Zea Longa神经功能评分检测大鼠神经功能;Western blot法检测皮质和海马Atg5、Atg14蛋白的表达水平。结果 与假手术组相比,模型组14 d后大鼠神经功能评分及大脑梗死面积升高(P<0.05)。与模型组相比,10、20、30 mg·kg^(-1)PIP干预组14 d后大鼠神经功能评分及大脑梗死面积均下降(P均<0.05)。与假手术组相比,模型组大鼠海马及皮质Atg5和Atg14蛋白表达水平均升高(P均<0.05)。与模型组相比,大鼠海马中20、30 mg·kg^(-1)PIP干预组Atg5、Atg14蛋白表达水平均下调(P均<0.05);大鼠皮质中30 mg·kg^(-1)PIP干预组Atg5和Atg14蛋白表达水平均下调(P均<0.05)。结论 PIP可降低缺血性脑卒中大鼠海马和皮质Atg5、Atg14自噬蛋白表达水平并对神经功能具有保护作用。

Objective To investigate the effects of different concentrations of piperine on autophagy-related gene Atg5 and Atg14 autophagy proteins and neurological function in the cortex and hippocampus of ischemic stroke rats.Methods A permanent middle cerebral artery occlusion(p MCAO)in vivo model was established to confirm the effects of piperine(PIP)on the autophagy proteins of Atg5,Atg14 and neural function in the cortex and hippocampus of ischemic stroke rats by gavage once a day.The experiment was divided into five groups:sham-operated group,model group,10 mg·kg^(-1) PIP intervention group,20 mg·kg^(-1) PIP intervention group and 30 mg·kg^(-1) PIP intervention group.TTC staining method was used to detect the cerebral infarct area of rats.The Zea Longa neurological function score was used to detect the neurological function of rats.Western blot method was used to detect the changes in the expression levels of Atg5 and Atg14 proteins in the cortex and hippocampus.Results Compared with the sham-operated group,the neurological function score and cerebral infarction area of the rats in the model group increased after 14 days(P<0.05).Compared with the model group,the neurological function score and cerebral infarction area of the rats were decreased after 10,20 and 30 mg·kg^(-1) PIP intervention for 14 days(P all<0.05).Compared with the sham-operated group,the expression levels of Atg5and Atg14 in the hippocampus and cortex of the model group were increased(P all<0.05).Compared with the model group,the protein expression levels of Atg5 and Atg14 were down-regulated in the rat hippocampus in the 20 and 30 mg·kg^(-1) PIP intervention groups(P all<0.05).The expression levels of Atg5 and Atg14 proteins in the rat cortex were down-regulated in the 30 mg·kg^(-1) PIP intervention group(P all<0.05).Conclusion Piperine can reduce the autophagy protein expression levels of Atg5 and Atg14 in hippocampus and cortical neurons of rats with ischemic stroke and has a protective effect on neurological function.