细叶远志皂苷调控胆碱能神经环路改善血管性痴呆小鼠认知功能障碍的研究

Research about Tenuifolin improving cognitive impairment of mice with vascular dementia by regulating cholinergic circuits

目的验证细叶远志皂苷调控胆碱能神经环路改善血管性痴呆(VD)小鼠认知功能障碍的作用。方法取48只雄性B6小鼠,采用双侧颈总动脉反复缺血-再灌注(2VO)法制备小鼠VD模型,并随机分为4组:VD模型组、假手术(Sham)组、细叶远志皂苷(Ten)治疗组、多奈哌齐阳性对照组四组。其中VD模型组只造模不做治疗,Sham组只分离双侧颈总动脉,不进行动脉夹夹闭等操作。Ten治疗组以细叶远志皂苷(10 mg/kg)灌胃治疗,多奈哌齐阳性对照组以多奈哌齐(3 mg/kg)灌胃治疗。Morris水迷宫检验小鼠的学习记忆能力,取脑制备脑片,运用免疫组化及Western blot方法检测各组小鼠胆碱能神经环路中胆碱乙酰转移酶(ChAT)蛋白的表达水平。结果 Morris水迷宫显示Ten治疗组小鼠的学习记忆能力显著高于VD模型组小鼠(P<0.01);免疫组化证实2VO法造模成功,且Ten治疗组小鼠海马区ChAT阳性神经元细胞数明显多于VD模型组小鼠(P<0.05);Western Blot结果显示Ten治疗组及多奈哌齐阳性对照组小鼠胆碱能神经环路ChAT蛋白表达的平均光密度值与内参抗体GAPDH的比值显著高于VD模型组小鼠(P<0.01)。结论细叶远志皂苷能够通过上调VD小鼠胆碱能神经环路中ChAT蛋白水平的表达,改善其学习和记忆能力。

Objective To prove the hypothesis that Tenuifolin can improve cognitive impairment of mice with vascular dementia by regulating cholinergic circuits through experimental investigation. Methods 48 male B6 mice were taken to prepare VD model by bilateral common carotid artery ischemia reperfusion（ 2 VO）,and they were randomly divided into 4 groups： VD model group,sham operation（ Sham） group,Tenuifolin treatment（ Ten） group and Donepezil positive control group. The VD model group was not given any treatment,while the Sham group only separated the bilateral common carotid arteries without clamping the artery clamp. The Ten group was treated with tenuifolin（ 10 mg/kg）. The Donepezil positive control group was treated with donepezil（ 3 mg/kg）. Morris water-maze tests were investigated to test the learning and memory ability of the mice. After the tests,the four groups of mice were killed and brain slices were prepared from the brains. The expression of ChAT protein in the cholinergic circuits of mice was detected by immunohistochemical analysis and Western blot. Results The Morris water-maze results showed that the learning and memory ability of the mice in the Ten treatment group was significantly higher than that of the VD model group（ P〈0. 01）. The Immunohistochemical analysis confirmed the effects of 2 VO method. And the number of ChAT positive neurons in the hippocampus of the Ten treatment group was significantly more than that of the VD model group（ P〈0. 05）. Western Blot results showed that Ten treated mice cholinergic expression of cholinergic circuits average optical density value of ChAT protein and the ratio of internal antibody of GAPDH was significantly higher than that of VD in the model group（ P〈0. 01）. Conclusion Tenuifolin can improve the ability of learning and memory of mice with vascular dementia by regulating expression level of ChAT protein in cholinergic circuits.