Apelin-13对局灶性脑缺血-再灌注损伤大鼠脑组织脑源性神经营养因子及受体表达的影响

Effect of Apelin-13 on the expression of brain-derived neurotrophic factor and tyrosine kinase B in the focal cerebral isehemia-reperfused injury rats

目的观察Apelin-13对局灶性脑缺血-再灌注损伤大鼠缺血区皮层脑源性神经营养因子(BDNF)和及其受体酪氨酸激酶B(TrkB)表达的影响。方法采用线栓法建立大鼠大脑中动脉缺血-再灌注损伤模型。SD雄性大鼠随机分为假手术组、模型组和Apelin-13(0.1、1.0和10.0μg/kg)处理组。缺血-再灌注损伤大鼠在缺血2 h后再灌注24 h,Apelin-13在再灌注前15 min进行侧脑室注射。采用实时定量PCR和Western blot检测BDNF和TrkB mRNA和蛋白的表达。结果与假手术组比较,模型组大鼠脑梗死侧皮层BDNF和TrkB mRNA和蛋白的表达显著性增加,BDNF mRNA相对表达量分别为(100.00±0.00)%和(138.54±7.63)%;TrkB mRNA相对表达量分别为(100.00±0.00)%和(121.74±8.73)%。BDNF蛋白相对表达量分别为(0.25±0.04)和(0.38±0.05);TrkB蛋白相对表达量分别为(0.23±0.03)和(0.36±0.04),差异均有统计学意义(t=9.45、10.79、10.37、8.76,均P<0.05)。与模型组比较,1.0和10.0μg/kg Apelin-13处理组大鼠脑梗死侧皮层BDNF和TrkB的表达均显著性增加,BDNF mRNA相对表达量分别为(138.54±7.63)%、(158.69±11.37)%和(189.31±13.74)%;TrkB mRNA相对表达量分别为(121.74±8.73)%、(149.25±9.46)%和(166.41±13.74)%。BDNF蛋白相对表达量分别为(0.38±0.05)、(0.57±0.06)和(0.71±0.08);TrkB蛋白相对表达量分别为(0.36±0.04)、(0.51±0.07)和(0.68±0.07),呈浓度依赖性,差异均有统计学意义(F=8.84、11.12、9.72、10.48,均P<0.05)。结论 Apelin-13对大鼠局灶性脑缺血-再灌注损伤有保护作用,其机制可能与上调BDNF及受体TrkB的表达有关。

Objective To observe the effects of Apelin-13 on the expressions of brain-derived neurotrophic factor （BDNF） and tyrosine kinase B （TrkB） in the focal cerebral isehemia-reperfused rats.Methods The rats models of focal middle cerebral artery ischemia-reperfusion were established by filament in SD male rats.The rats were randomly divided into the sham,model and Apelin-13 （0.1,1.0 and 10.0 μg/kg） treatment group.After 2 h ischemia,the focal middle cerebral artery was followed by 24 h reperfusion in rats with isehemia-reperfused injury.Apelin-13 was administrated by the intracerebroventricular injection 15 minutes before reperfusion.The mRNA and protein expressions of BDNF and TrkB in cerebral cortex were measured by real-time PCR and Western blot respectively.Results Compared with the sham group,the mRNA and protein expressions of BDNF and TrkB in cerebral cortex were significantly increased in the models of ischemia-reperfusion group,the relative mRNA expressions of BDNF were （100.00±0.00）％and （138.54±7.63）％ respectively; the relative mRNA expressions of TrkB were （100.00±0.00）％ and （121.74±8.73）％respectively.The relative protein expressions of BDNF were （0.25±0.04） and （0.38±0.05） respectively; the relative protein expressions of TrkB were （0.23±0.03） and （0.36±0.04） respectively,with significant differences （t=9.45,10.79,10.37,8.76,all P ＜ 0.05）.Compared with the models of ischemia-reperfusion group,the mRNA and protein expressions of BDNF and TrkB in cerebral cortex were significantly increased in the 1.0 and 10.0 μg/kg Apelin-13 treatment group,the relative mRNA expressions of BDNF were（138.54±7.63）％,（158.69±11.37）％ and （189.31±13.74）％ respectively; the relative mRNA expressions of TrkB were （121.74±8.73）％,（149.25±9.46）％ and （166.41±13.74）％ respectively.The relative protein expressions of BDNF were （0.38±0.05）,（0.57±0.06） and （0.71±0.08） respectively; the relative protein expressions of TrkB were （0.36±0.04）,（0.51± 0.07） and （0.68±0.07） respectively,with significant differences （F=8.84,F=11.12,F=9.72,F=10.48,all P ＜ 0.05）.Conclusion Apelin-13 protects the ischemia-reperfusion injury,the mechanism of which may be related with up-regulation of BDNF and TrkB.