地黄益智方通过表观遗传调控Nrf2及其靶基因保护氧化应激神经损伤作用研究

β-amyloid (Aβ) plays an important role in the pathogenesis of Alzheimer's disease (AD). Aβ may induce reactive oxygen species (ROS) and lead to nerve damage through oxidative stress. Alleviating oxidative stress mediated damage is important strategy for prevention and treatment of AD. Nrf2 is an anti-oxidative stress gene and regulated by epigenetics. Di-Huang-Yi-Zhi formula (DHYZF) is an empirical herbal formula of Longhua hospital for AD treatment. DHYZF can improve cognitive abilities in AD patients, ameliorate learning and memory abilities in AD rats and may be related to antioxidation through up-regulation of Nrf2. Further study is urgently needed to explore the regulatory mechanism of DHYZF on Nrf2 expression.. The project plans to evaluate the therapeutic effects of DHYZF on AD and oxidative stress mediated cytomembrane, mitochondria and DNA damage and apoptosis in PC12 neuronal cells and APP/PS1 double transgenic AD mice. Based on epigenetics (DNA methylation, histone acetylation and miRNA), to explore the regulatory mechanism of DHYZF on Nrf2 expression. The project will also study the effects of DHYZF on Nrf2 target genes expression, including HO-1, NQO1 and γ-GCS. These studies may provide new insight into Traditional Chinese medicine based prevention and treatment for AD.

Aβ蛋白在阿尔茨海默病（Alzheimer's disease，AD）发病中起重要作用，可以诱生活性氧，介导氧化应激神经损伤，保护氧化应激损伤是防治AD的重要策略。Nrf2是抗氧化应激基因，其表达受表观遗传的调控。地黄益智方（专利号ZL200810204715.3）是龙华医院治疗AD协定方，可提高AD患者的认知功能，改善AD大鼠的学习记忆能力，与上调Nrf2抗氧化应激相关，但其调控机制亟待研究。. 项目拟进一步在PC12神经细胞和APP/PS1双转基因AD小鼠模型中，研究地黄益智方对AD的治疗作用，及其对氧化应激介导的神经细胞膜、线粒体和DNA损伤及细胞凋亡的保护作用；从表观遗传（DNA甲基化、组蛋白乙酰化和miRNA）的角度，揭示地黄益智方对Nrf2基因表达的调控机制；研究地黄益智方对Nrf2靶基因HO-1、NQO1和γ-GCS表达的作用；为中医药防治AD提供新的基础。

保护氧化应激损伤是防治阿尔茨海默病（Alzheimer's disease，AD）的重要策略。Nrf2是抗氧化应激基因，其表达受表观遗传的调控。地黄益智方由熟地黄、山茱萸、丹参、石菖蒲、茯神和益智等组成，该处方的制剂工艺、质量标准稳定可控、可重复。.细胞模型研究以氧化应激损伤为切入点，研究地黄益智方对H2O2诱导的PC12细胞损伤的保护作用及可能机制。研究结果显示地黄益智方对H2O2诱导PC12细胞氧化应激损伤具有保护作用，保护作用可能机制：降低活性氧生成，抑制细胞凋亡；增加GSH、GPx、GR、SOD活性，减少MDA、8-OhdG产生；调节HDAC和HAT活性，通过组蛋白乙酰化上调Nrf2表达，升高HO-1、NQO1和GCLC表达。.动物模型研究选用3月龄雄性APP/PS1转基因小鼠，研究地黄益智方对APP/PS1小鼠神经功能保护作用及可能机制。研究结果显示地黄益智方可以改善APP/PS1转基因小鼠的学习和记忆能力、神经元突触的超微结构；降低活性氧生成和Caspase-3活性，抑制细胞凋亡；其机制可能与调节HDAC和HAT活性，促进组蛋白乙酰化，上调Nrf2及其靶基因HO-1、NQO1和GCLC表达相关。 .项目在PC12神经细胞和APP/PS1双转基因AD小鼠模型中，系统研究了地黄益智方对AD的治疗作用，及其对氧化应激损伤的保护作用；从表观遗传角度，探讨了地黄益智方对Nrf2基因表达的调控机制。本研究为中医药治疗AD提供了新的基础。