电针抑制脑缺血再灌注损伤大鼠细胞凋亡机制研究

Mechanisms of inhibiting apoptosis in rats with cerebralischemia-reperfusion injury by electroacupuncture

目的:从肌醇依赖性激酶1α(IRE1α)/激活性蛋白激酶C受体1(RACK1)分子开关探讨电针干预脑缺血再灌注损伤(CIRI)大鼠细胞凋亡机制。方法:64只SD大鼠随机分成假手术组、模型组、依达拉奉组、电针组,每组16只。线栓法制备CIRI大鼠模型后,依达拉奉组、电针组每12 h分别予依达拉奉溶液给药和“内关”“百会”穴电针干预,共5次。Longa法评价大鼠神经功能缺损症状;TTC染色法观察大鼠脑组织缺血损伤情况;TUNEL染色法检测细胞凋亡指数;Western blotting法检测RACK1、p-IRE1α、CHOP蛋白表达。结果:与假手术组比较,模型组大鼠神经功能缺损评分、凋亡指数、CHOP表达升高,RACK1表达降低,差异有统计学意义(均P<0.01)。与模型组比较,治疗后电针组、依达拉奉组大鼠神经功能缺损评分、凋亡指数降低,电针组大鼠RACK1、p-IRE1α表达升高,CHOP表达下降,差异有统计学意义(均P<0.01)。治疗后与模型组比较,依达拉奉组大鼠p-IRE1α表达升高,CHOP表达下降,差异有统计学意义(均P<0.01)。依达拉奉组与电针组大鼠神经功能缺损评分、细胞凋亡指数比较,差异无统计学意义(均P>0.05)。电针组大鼠RACK1表达高于依达拉奉组,差异有统计学意义(P<0.01)。结论:电针可抑制CIRI大鼠脑组织内细胞凋亡,减轻脑损伤,其机制可能与针刺启动IRE1α/RACK1分子开关相关。

Objective:To investigate mechanism of electroacupuncture intervention on cell apoptosis in rats with cerebral ischemia-reperfusion injury was related to inositol-requiring enzyme 1α(IRE1α)/receptor for activated C kinase 1(RACK1)molecular switch.Methods:Sixty-four SD rats were randomly divided into sham operation group,model group,edaravone group and electroacupuncture group,16 rats in each group.After CIRI rat model was made by thread embolism,the edaravone group and the electroacupuncture group were given edaravone solution and electroacupuncture intervention at points Neiguan and Baihui every 12 hours,respectively,foR5 times.Longa method was used to evaluate the symptoms of neurological deficit in rats.TTC staining was used to judge the ischemic injury of brain tissue in rats.TUNEL staining was used to detect apoptosis index.The relative expression of RACK1,p-IRE1αand CHOP protein were detected by Western blotting.Results:Compared with the sham operation group,neurological deficit score,apoptosis index,CHOP expression elevated and RACK1 expression reduced in the model group were significantly increased,difference statistically significant(all P<0.01).Compared with the model group,neurological deficit score and apoptosis index of rats in the electroacupuncture group and the edaravone group decreased,expression of RACK1 and p-IRE1αin the electroacupuncture group increased,and expression of CHOP decreased,difference statistically significant(all P<0.01).After treatment,compared with the model group expression of p-IRE1αin the edaravone group increased and CHOP decreased,difference statistically significant(all P<0.01).Compared with the edaravone group,there was no significant difference in neurological deficit score and apoptosis index in electroacupuncture group(all P>0.05).Expression of RACK1 in the electroacupuncture group was increased than that in the edaravone group(P<0.01).Conclusion:Electroacupuncture can inhibit apoptosis in brain tissue of CIRI rats and reduce brain injury.Its mechanism may be related to activation of IRE1α/RACK1 molecular switch by acupuncture.