左旋半胱氨酸通过调控PI3K/AKT通路减轻大鼠脑缺血损伤的研究  

L-cysteine attenuates cerebral ischemic injury in rats by regulating PI3K/AKT pathway

作　　者：邵丽丽 陆琦 潘学威 朱思亮 SHAO Lili;LU Qi;PAN Xuewei;ZHU Siliang(Wenzhou Central Hospital,Wenzhou 325000,Zhejiang,China)

机构地区：[1]温州市中心医院,浙江省温州325000

出　　处：《现代实用医学》2023年第6期731-736,共6页Modern Practical Medicine

基　　金：温州市基础性医疗卫生科研项目(Y20210910)。

摘　　要：目的探讨左旋半胱氨酸(L-Cys)通过调控PI3K-Akt信号通路对缺血性脑卒中的神经保护作用及机制。方法使用大脑中动脉闭塞模型(MCAO),将SD大鼠分为Sham组(假手术组)、MCAO组、L-Cys组(MCAO+LCys)、LY294002组[MCAO+PI3K-Akt通路特异性抑制剂(LY294002)]、L-Cys+LY294002组(MCAO+L-Cys+LY294002)。建模前30min给相关组别腹腔注射10μ10.5 mg/ml的LY294002;建立MCAO模型后,使用L-Cys(5mg/kg)于术后2、24、48 h连续腹腔注射3次。Sham组和MCAO组给予相同量的0.9%氯化钠注射液腹腔注射。苏木精-伊红(HE)和TUNEL染色评价脑组织完整性和神经元凋亡程度。采用qRT-PCR、Western blot和ELISA测定Bad、Bax、Bcl-2、Bim、P53、MDM2、Akt、PI3K、p-Akt、p-PI3K和Cyt-C表达情况。结果与Sham组相比,MCAO组脑组织细胞凋亡率明显增加,脑功能评分明降低,促凋亡因子(Bad、Bax和Bim)的表达显著上调,抗凋亡因子Bcl-2的表达显著下调(均P<0.05);与MCAO组相比,L-Cys组脑组织细胞凋亡率明显减少,脑功能评分明显提高,Bad、Bax和Bim表达显著下调,Bcl-2表达显著上调,p53表达显著减弱(均P<0.05)。结论L-Cys减轻脑缺血大鼠的神经损伤,这种作用可能受PI3K-Akt信号通路激活调控。Objective To investigate the neuroprotective effect ofL-Cys on cerebral ischemia-reperfusion injury through the PI3K-Akt signaling pathway.Methods After establishing the model of middle cerebral artery occlusion(MCAO),male Sprague-Dawley rats were allocated to five groups as follows:sham,MCAO,L-Cys(MCAO+L-Cys),LY294002[MCAO+LY294002(PI3K-Akt pathway specific inhibitor)land L-Cys+LY294002(MCAO+L-Cys+LY294002)].Hem-atoxylin and eosin(HE)and terminal deoxynucleotidyltransferasedUTP nick-end labeling(TUNEL)staining were used to evaluate the pathological changes of brain tissue and the degree of neuronal apoptosis.Real-time quantitative polymerase chain reaction(qRT-PCR),western blot analysis and enzyme-linked immunosorbent assays were used to measure the ex-pression of Bad,Bax,Bcl-2,Bim,P53,MDM2,Akt,PI3K,p-Akt,p-PI3Kand Cyt-C.ResultsCompared with the MCAO group,brain tissue cell apoptosis was significantly reduced in the L-Cys group,and the brain function score was significan-tly improved.In addition,the expression of pro-apoptotic factors(Bad,Bax,and Bim)was significantly downregulated in the L-Cys group,while expression of the anti-apoptotic factor Bcl-2 was significantly upregulated,and expression of the apoptotic gene p53 was also significantly attenuated.Moreover,this neuroprotective effect was attenuated by the PI3K-Akt signaling pathway inhibitor(LY294002).Conclusions The results confirmed the neuroprotective effects ofL-Cys in rats with ischemia-reperfusion injury and indicate that these effects on the brain are partly generated by activation of the PI3K-Akt signaling pathway.

关 键 词：左旋半胱氨酸 神经损伤 细胞凋亡 缺血再灌注 PI3K-Akt通路 

分 类 号：R743[医药卫生—神经病学与精神病学]