淫羊藿苷对中动脉阻塞大鼠脑源性神经营养因子及酪氨酸激酶受体B表达的影响

Effects of icariin on BDNF and Trk B of rats with focal cerebral ischemia-reperfusion injury

目的:探讨淫羊藿苷对中动脉阻塞模型大鼠脑源性神经营养因子(brain derived neurotrophic factor,BDNF)、酪氨酸激酶受体B(Trk B)表达的影响及其对脑缺血再灌注损伤的保护作用。方法:本研究采用插线法制作大鼠中动脉阻塞模型(MCAO)。成年雄性SD大鼠被随机分为四组:假手术组;缺血再灌注组;淫羊藿苷高剂量组:100 mg/kg,淫羊藿苷中剂量组:50 mg/kg,淫羊藿苷低剂量组:25mg/kg和剂量为10 mg/kg的尼莫地平阳性对照组。观察淫羊藿苷对神经功能缺损评分和脑含水量的影响,运用蛋白质印迹法(Western Blot)检测BDNF蛋白和Trk B的表达;苏木精伊红(H&E)染色观察脑组织的形态学改变;并运用细胞凋亡检测(TUNEL法)的方法检测海马CA1区神经元的凋亡情况。结果:50mg/kg和100 mg/kg的淫羊藿苷均可改善MCAO大鼠神经损伤症状;降低其脑含水量;减轻脑缺血再灌注损伤的脑组织形态学改变及CA1区神经元凋亡;上调BDNF和Trk B的表达。其中100 mg/kg效果最为明显,而最低剂量25 mg/kg几乎为无效剂量。结论:淫羊藿苷对脑缺血再灌注具有保护作用,此作用可能是由上调BDNF与Trk B的表达引起的。

Objective： To investigate protective effect and the effect about brain-derived neurotrophic factor（ BDNF）,tyrosine kinase receptor B（ Trk B） on cerebral ischemia-reperfusion injury in rats. Methods： using Plug-line method make focal cerebral ischemia and reperfusion of middle cerebral artery occlusion model of rat. Adult SD rats were divided into four groups： sham group; icariin-treatment groups： a dose of100 mg / kg,icariin- treatment groups： a dose of 50 mg / kg,icariin-treatment groups： a dose of 25 mg / kg; ischemia-reperfusion group and nimodipine group： a dose of 10 mg / kg. The effects of Icariin on Neurological deficit scores and the Brain water content were detected. Using Western blotting to detect the expression of BDNF and Trk B. Make HE to observe morphological changes of brain tissue. And the TUNEL method was used to detect neurons apoptosis in rat hippocampal CA1. Results： Icariin（ 50 mg / kg,100 mg / kg） can improve the nerve damage symptoms of MCAO rat; Brain water content was reduced; Brain morphological changes and neuronal apoptosis was relieved; The expression of BDNF and Trk B was increased. In it,100 mg / kg was most obvious,and the lowest dose 25 mg / kg was almost ineffective. Conclusion：Icariin can protect cerebral ischemia-reperfusion injury,This effect may be regulated by increasing the expression of BDNF and Trk B.