Klotho对缺血性脑损伤的抗氧化保护作用及机制研究

Anti-oxidative protective effect and mechanism of klotho on ischemic brain injury

本实验通过侧脑室注射慢病毒载体编码的小鼠klotho基因(LV-KL),研究klotho过表达对缺血再灌损伤的抗氧化保护作用及潜在机制。C57Balc/6J小鼠双侧侧脑室注射慢病毒4周后,通过双侧颈总动脉结扎法(2VO)建立小鼠全脑缺血再灌注模型。应用神经行为学评分、Nissl染色、q PCR及Western blot等指标研究klotho对脑缺血的作用及相关抗氧化机制。实验结果表明,klotho过表达明显改善了2VO小鼠的神经行为学障碍,改善海马CA1区和纹状体区(CPu)神经元损伤。同时,LV-KL增加了脑内锰超氧化物歧化酶(Mn-SOD)和过氧化氢酶(CAT)的表达,减少了脑内丙二醛(MDA)含量。Western blot结果显示,klotho过表达抑制了Akt和Fox O1的磷酸化,表明klotho的抗氧化作用可能与抑制Akt/Fox O1信号通路有关。由此可见,利用klotho或klotho增强剂可以减缓衰老相关的klotho表达下降,而本实验也为治疗老年急性缺血性脑卒中提供了一种新的研究方向。

Present study was designed to investigate the effects and underlying antioxidant mechanism of klotho overexpression through an intracerebroventricular injection of a lentiviral vector that encoded murine klotho（LV-KL） on cerebral ischemia injury.Four weeks after the injection of lentivirus into the lateral ventricle of C57 Balc/6 J mice,a mouse model of global cerebral ischemia-reperfusion was established by bilateral common carotid artery occlusion（2 VO）.Klotho overexpression significantly improved neurobehavioral deficits and increased the number of survival neurons in the hippocampal CA1 and caudate putamen subregions.The overexpression also decreased malondialdehyde（MDA） content in brain,while mitochondrial manganese-superoxide dismutase（Mn-SOD） and catalase（CAT） expression in brain were increased.Moreover,klotho overexpression decreased Akt and forkhead box class O1 phosphorylation.These findings suggest that klotho may compensate for its aging-related decline to provide a promising therapeutic approach for the acute ischemic stroke during aging.