基于PI3K/Akt和MAPK/Erk信号通路串扰的益肺宣肺降浊方调控血管性痴呆的神经保护机制

Vascular dementia is a clinical common disease, wich recently lack effective treatment methods, and has become an important factor to damage human heal th. To search for new therapeutic targets and strategies has become the rese arch hotspots and difficulties of modern medicine. It has been proved that PI3K/Akt and MAPK/Erk signaling pathways are respectively closely related to the pathogenesis of vascular dementia, and there is Crosstalk effects between them, which plays an important role in the in the pathogenesis and treatment of vascular dementia. Traditional Chinese medicine has obvious effect on Vascular dementia, xuanfeiyifeijiangzhuo decoction can treat the Vad according to the key pathogenesis. Our research group found by preliminary study that xuanfeiyifeijiangzhuo decoction could improve the ability of the ischemia reperfusion rats by the mechanisms of magnifying the signal transduction of PKA/CREB and cAMP signal pathway, inhibiting the apoptosis. It has been proved that the phosphorylation of CREB is regulated by several singnal pathway such as cAMP signal pathway, Ca2+ -CaMK signal pathway、PI3K/Akt signal pathway, and MAPK/Erk signal pathway. This research will research the molecular mechanism of the treatment for Vad with xuanfeiyifeijiangzhuo decoction from the aspect of the crosstalk relationship between PI3K/Akt and MAPK/Erk signal pathway, by using the Vad rat model, and experimental techniques, which includes Western Blot, qRT-PCR, immune coprecipitation, immunofluorescence and electron microscope technique, and provide effective treatment methods and theories basis.

血管性痴呆是临床常见病症，目前缺乏有效的治疗手段，已成为危害人类健康的重要因素。探求新的治疗靶点及策略已成为现代医学研究的热点与难点。研究表明PI3K/Akt和MAPK/Erk通路之间存在串扰作用，在血管性痴呆的发病及其治疗过程中扮演着重要角色。课题组前期研究发现益肺宣肺降浊方增强PKA/CREB信号转导，以及cAMP信号通路和阻抑细胞凋亡而发挥了其提高缺血再灌注大鼠学习记忆能力的作用。由于目前已知CREB的磷酸化受cAMP、Ca2+ -CaMK、PI3K/AKt、MAPK/Erk等多种信号转导通路的调控。基于以上研究基础和国内外研究概况，该研究以VaD模型大鼠为研究对象，并运用Western Blot、qRT-PCR、免疫共沉淀、免疫荧光、电镜等技术，从PI3K/Akt和MAPK/Erk信号通路的串扰关系探讨该治疗方法的分子机制，为临床应用该技术防治VaD提供有效的治疗方法和理论依据

近年来，国内外研究者们做出了大量的基础研究和临床探索，应用多种方法治疗VaD，包括针对原发性血管性疾病的治疗，抗血小板聚集治疗，如阿司匹林等改善脑循环；降脂治疗，如他汀类药物降低胆固醇等；此外还有一些针对VaD的对症治疗（认知障碍），如维生素E、维生素C和银杏叶制剂等用于VaD的辅助治疗，胆碱酯酶抑制剂多奈哌齐，以及吡拉西坦、尼麦角林等改善其记忆功能。对血管性痴呆的认识，中医普遍认为病位在脑，涉及心、肝、脾、肾,病因为虚、瘀、痰等方面。但从这些信息分析，其病机关键皆与肺相关。首先，肺气充盛可助养五脏之气，肺气盛，助肾则藏精生髓，助脾则散布精气，助心则资宗气运血脉，助肝则柔筋疏泄。其次，若肺气失于宣发，则精气不能上养脑神，使髓海失养，灵机失用；同时，肺气不足，气血津液不能正常输布和排泄，使痰浊、瘀血等病理产物蓄积，肺气失于宣发，痰浊阻遏脑窍，蒙蔽神志，发为痴呆。因此，虽然血管性痴呆的中医关键病机部位在于五脏，却可通过益肺宣肺降浊之法，调养五脏，补肾填精，祛瘀、化痰，清除病因。因此，以中医理论为指导，发挥益肺宣肺降浊法在VaD治疗中的重要作用，并探讨其作用机制将对VaD的防治研究将有可能为寻找抗VaD新药研究作出重要贡献。. 结果显示益肺宣肺降浊方呈剂量依赖性改善VaD大鼠的记忆能力及脑海马组织的病理及降低神经元凋亡。上调EGFR激活PI3K/AKt 信号通路与MAPK/Erk 信号通活性。. 科学意义：揭示了临床效验方益肺宣肺降浊方治疗 VaD 的作用机制与激活VEGF受体 EGFR调节 PI3K/AKt 信号通路与MAPK/Erk 信号通路活性相关，这一研究成果为揭示益肺宣肺降浊法的科学有效性奠定了基础；本项目的研究，还有助于为从肺论治血管性痴呆提供新的科学依据，为诠释中医整体观防治疾病奠定基础。