短期鼻腔给予染料木黄酮对减轻大鼠脑梗死后神经元损伤的作用

SHORT-TERM INTRANASAL DELIVERY GEN IN OVARIECTOMIZED RATS PROVIDES ANTI-INFLAMMATORY INJURY AFTER CEREBRAL INFARCTION

目的观察短期鼻腔给予染料木黄铜(Genistein,Gen)对脑梗死后脑内神经元的影响,为探索治疗缺血性脑损伤的有效策略提供一定依据。方法成年双侧切除卵巢的SD大鼠随机分为假手术组(Sham)、脑梗死组(CI)和Gen处理组,各组分为14d和2个月时间点。通过光化学法建立脑梗死(CI)模型;采用TTC染色法检测脑梗死面积;平衡木、转棒及可视游泳实验检测大鼠的行为学功能;免疫荧光染色法观察大鼠皮质缺血区生存神经元标志物NeuN/凋亡早期标志蛋白Annexin V,以及小胶质细胞标志蛋白Iba1水平。结果(1)CI后14d,TTC染色显示CI组脑皮层较Sham组和Gen处理组具有明显梗死区域;(2)CI后14d,行为学实验显示CI组大鼠较Sham组和Gen处理组大鼠有显著的行为功能损伤;(3)CI后2个月,CI组大鼠脑皮层损伤区NeuN阳性细胞数量较Sham组和Gen处理组显著减少,而Annexin Ⅴ阳性细胞数量显著增加;(4)CI后2个月,与Sham组比较,CI组大鼠脑皮质损伤区Iba1免疫荧光强度明显增加,而短期鼻腔给予Gen可显著降低Iba1表达。结论短期鼻腔给予Gen可降低脑梗死面积、改善行为功能,减轻神经元损伤,其机制可能与Gen减轻脑内炎症有关。

Objective To observe the effect of short-term Genistein（Gen）by intranasal delivery on the inflammation of neuron after cerebral infarction,and to provide potential strategies for treating ischemic brain injury.Methods SD adult rats were bilateral ovariectomized and randomly divided into sham group,cerebral infarction group（CI）and Gen treatment group,and then each group was divided into subgroups,14 d and 2 months after CI.CI animal model was established by photochemical method,and TTC staining was used to examine the infarction size.Balance beam,rotarod test,visible test were used to detect the animal outcome after CI and immunofluorescence staining was carried out to investigate the markers of survival neurons（NeuN）or earl apoptotic cells（Annexin Ⅴ）,as well as Iba1,a microglia in ischemic cortex region.Results（1）TTC staining results showed that,at 14 d after CI,the CI group had obvious increased infarction size in cerebral cortex compared with sham and Gen treatment groups.（2）The results of balance beam,rotating rod and visual swimming tests indicated that the rats in CI group had significant outcome injury compared with the rats in sham and Gen groups at 14 d after CI.（3）At 2 months after CI,the number of NeuN-positive cells in cerebral cortex injury region of CI animals was significantly decreased compared with sham and Gen treatment groups.On the contrary,the number of Annexin V-positive cells was significantly increased.（4）At 2 months after CI,compared with sham group,the immunofluorescence intensity of Iba1 in the cerebral cortex injury region of CI animals was obviously enhanced,while Gen treatment markedly reversed the increase.Conclusion Short-term intranasal delivery of Gen prevents cortex neuronal injury and improves outcome after cerebral infarction,induces a neuroprotective role that may be related to anti-neuroinflammatory effect of Gen.