欧前胡素对血管性痴呆的保护作用及基于Nrf2/ARE信号通路的作用机制研究

Vascular dementia is one of the major diseases that threaten the human life and affected the quality of life, however, effective drug is very rare for the treatment of vascular dementia. Imperatorin is a naturally occurring furanocoumarin, which possess anti-inflammatory, blocking calcium channel and anti oxygen free radicals injury properties. Our previous study revealed that imperatorin can improve the learning and memory function of vascular dementia model on rat, but its mechanism has not been elucidated. So, in the present study, models of vascular dementia induced by permanent bilateral common carotid artery occlusion in rats and oxygen glucose deprivation injury on primary hippocampal neuronal cells were used to determine the expression of Nrf2, HO-1, NQO1, Bax、Bcl-2, Caspase-3 at protein or gene levels in hippocampus of vascular dementia rats with imperatorin, using the methods of direct fluorescent, immunohistochemistry, Real-time PCR, Western blot and electrophysiology. And further to clarify if the protective mechanism of vascular dementia with imperatorin is through regulating Nrf2/ARE signal pathway, reducing oxidative stress, inhibiting of nerve cell apoptosis. Our present study will provide more theoretical basis for the imperatorin on preventing and treating of vascular dementia and play a positive role on alleviating the social and economic pressures caused by people with dementia.

血管性痴呆是威胁人类生命、影响生活质量的主要疾病之一，但疗效卓著的药物十分稀少。欧前胡素是一种香豆素类化合物，具有抗炎、阻滞钙通道、抗氧自由基损伤作用。我们前期研究结果显示欧前胡素能改善血管性痴呆大鼠学习与记忆功能，但确切机制尚不明确。本课题以双侧颈总动脉永久性结扎术制备的血管性痴呆大鼠和原代海马神经元细胞氧糖剥夺损伤模型为研究对象，采用直接荧光法、免疫组化、Real-time PCR、Western blot和电生理等技术，观察欧前胡素对血管性痴呆大鼠海马组织中Nrf2、HO-1、NQO1、Caspase-3、Bax、Bcl-2 mRNA等转录和蛋白表达的影响，进一步阐明欧前胡素对血管性痴呆的神经保护机制是通过调控Nrf2/ARE信号通路，减轻氧化应激反应，抑制神经细胞凋亡而实现的。本项研究将为欧前胡素防治血管性痴呆提供更多的理论依据，对缓解痴呆症患者造成的社会和经济压力将起到积极作用。

血管性痴呆(Vascular dementia，VaD)严重影响了人们的生命健康和生活质量，给整个社会、家庭和患者本人带来了沉重的经济和精神负担，其已成为我国公共卫生领域面临的最大挑战之一。但是，其发病机制迄今尚未完全阐明，目前也尚无被食品和药物管理局正式批准用于治疗VaD的药物。因此，探讨VaD的发病机制并寻求能够有效防治VaD的药物有着重要的现实意义和实际应用价值。本研究着眼于祖国传统的中医药欧前胡素的优势，以双侧颈总动脉永久性结扎术制备的VaD大鼠和原代海马神经元细胞氧糖剥夺损伤模型为研究对象，采用细胞分离和培养、免疫细胞化学标记法、直接荧光法、PCR、Western blot和电生理等技术、细胞转染及干扰RNA(shRNA)沉默技术，试图阐明欧前胡素对VaD的神经保护机制是通过调控Nrf2/ARE信号通路，减轻氧化应激反应，抑制神经细胞凋亡而实现的。本项研究将为欧前胡素防治VaD提供更多的理论依据，为防治VaD药物的选择提供新的思路，对缓解痴呆症患者造成的社会和经济压力将起到积极作用。