田蓟苷调节AMPK/SIRT1/PGC1α信号通路对脑出血大鼠认知功能和神经元损伤的影响

Influences of Tilianin on Cognitive Function and Neuronal Damage in Rats with Cerebral Hemorrhage

目的:探讨田蓟苷(TIL)对脑出血(ICH)大鼠认知功能、神经元损伤及腺苷酸激活蛋白激酶(AMPK)/沉默调节蛋白1(SIRT1)/过氧化物酶体增殖活化受体γ辅助活化因子1α(PGC1α)信号通路的影响。方法:采用Ⅳ型胶原酶注射法构建ICH大鼠模型,将造模成功的ICH大鼠随机分为模型组(ICH组)、TIL组(16 mg/kg)、AMPK抑制剂组(Compound C组,250μg/kg)、TIL+AMPK抑制剂组(TIL+Compound C组),另设假手术组(Sham组),每组12只。采用改良的Garcia JH法、Morris水迷宫实验和敞箱实验评价大鼠的神经功能和认知功能;苏木素-伊红(HE)和脱氧核糖核苷酸末端转移酶介导的缺口末端标记(TUNEL)法行脑组织病理学和神经元凋亡观察;蛋白质印迹法(Western Blot)检测AMPK/SIRT1/PGC1α通路蛋白表达。结果:与Sham组相比,ICH组大鼠脑组织出现细胞核皱缩、排列紊乱等损伤,神经功能评分、穿越平台次数、垂直活动得分和水平活动得分、磷酸化AMPK(p-AMPK)/AMPK、SIRT1、PGC1α蛋白水平均明显下降(P<0.05),找寻平台时间、神经元凋亡率、半胱氨酸蛋白酶-3(Caspase-3)、B淋巴细胞瘤-2(Bcl-2)蛋白表达水平均明显增加(P<0.05);与ICH组相比,TIL组大鼠脑组织损伤减轻,神经功能评分、穿越平台次数、垂直活动得分和水平活动得分、p-AMPK/AMPK、SIRT1、PGC1α蛋白水平均明显增加(P<0.05),找寻平台时间、神经元凋亡率、Caspase-3、Bcl-2蛋白表达水平均明显降低(P<0.05);而Compound C组大鼠以上指标呈现相反的趋势。且TIL对ICH大鼠脑组织及认知功能的保护作用均被AMPK抑制剂Compound C减弱(P<0.05)。结论:TIL可能通过激活AMPK/SIRT1/PGC1α通路,改善ICH大鼠认知功能,减轻神经元损伤。

Objective:To investigate the influences of tilianin(TIL)on cognitive function and neuronal damage in rats with intracerebral hemorrhage(ICH).Methods:The ICH rat model was established byⅣcollagenase injection.The successful modeling ICH rats were randomly dvided into model group(ICH group),TIL group(16 mg/kg),AMP-activated protein kinase(AMPK)inhibitor group(Compound C group,250μg/kg),TIL+AMPK inhibitor group(TIL+Compound C group),and sham operation group(Sham group),with 12 rats in each group.The neurological and cognitive functions of rats were evaluated by modified Garcia JH method,Morris water maze test,and open-box test.The brain histopathology and neuronal apoptosis were observed by hematoxylin-eosin(HE)and Termina-l deoxynucleoitidyl Transferase Mediated Nick End Labeling(TUNEL)staining.The expression of AMPK/Sirtuin type 1(SIRT1)/peroxisome proliferator-activated receptor gamma coactivator 1α(PGC1α)pathway proteins was measured by Western Blot.Results:Compared with Sham group,nucleus shrinkage disordered arrangement and other damages was observed in the rat brain tissue,the neurological score,platform crossing times,vertical activity score,horizontal activity score,and phosphorylated AMPK(p-AMPK)/AMPK,SIRT1,PGC1αprotein levels decreased obviously(P<0.05),the searching platform time,neuron apoptosis rate,and Caspase-3,Bc-l 2 protein levels of ICH group increased obviously(P<0.05).Compared with ICH group,the brain tissue damage of TIL group reduced,the neurological deficit score,platform crossing times,vertical activity score,horizontal activity score,and p-AMPK/AMPK,SIRT1,PGC1αprotein levels increased obviously(P<0.05),the searching platform time,neuron apoptosis rate,and Caspase-3,Bc-l 2 protein levels decreased obviously(P<0.05).The above indicators in Compound C group showed the opposite trends.The protective effects of TIL for brain tissue and cognitive function of ICH rats were attenuated by AMPK inhibitor Compound C(P<0.05).Conclusion:TIL may improve cognitive function and reduce neuronal damage in ICH rats by activating AMPK/SIRT1/PGC1αpathway.