C60衍生物通过调控Nrf2/NF-κB炎症平衡体系抑制小胶质细胞活化的研究

Mounting evidence indicates that microglial activation contributes to neuronal damage in neurodegenerative disorders. Activated microglia can induce and release neurotoxic proinflammatory factors as well as reactive oxygen species (ROS), which lead to inflammation-mediated neuronal cell death.Therefore, control of microglial activation may alleviate the progression of neurodegeneration,suggesting that development of anti-inflammatory or antioxidant drugs could provide a potential therapeutic approach for neurodegenerative conditions.Research in the field of water-soluble C60 fullerene derivatives has significantly increased due to the broad range of biological activities found for these compounds.As the peculiar structure of C60 fullerenes not only serve as "radical sponge", but also may possess higher physical stability when in contact with biological fluids, show good biocompatibility in vivo and in vitro, and pass through the blood-brain barrier, the exceptional radical-scavenging property and biophysical properties of fullerene make them promising pharmacophore for development of drugs targeting neurodegenerative diseases. Although C60 fullerene derivatives have been reported to possess excellent neural protective efficacy in a broad spectrum of neurodisorders, the effect of C60 fullerene derivatives on microglial activation remains to be elucidated.The research proposed here will be undertaken to investigate the effects of C60 fullerene derivatives (C60-OH,C60-COOH)on LPS-induced inflammatory responses using a microglial cell line in vitro and animal models of LPS-induced inflammation in mouse hippocampus. We will elucidate the cellular and molecular mechanisms underlying anti-inflammatory activity of C60 nanoparticles, focusing on whether C60 fullerene derivatives activate antioxidant defense via the Nrf2 pathway and inhibit inflammation via NF-κB inhibition, and whether C60 nanoparticles-induced activation of Nrf2 signaling could be a major cellular mechanism mediating anti-inflammatory effect of C60 nanoparticles. This proposal will provide mechanistic insights into the therapeutic potential of C60 nanoparticles in neuronal cell damage induced by activated microglia, and open the possibility of developing fullerene derivatives with potent biomedical applications in neurodegenerative disorders.

脑神经退行性病变是严重危害人类健康的神经系统疾病，目前尚无理想防治药物。小胶质细胞活化介导的炎性神经变性损伤是多种脑神经退行性病变的主要致病机制，因此抑制小胶质细胞活化是防治这类疾病的重要干预策略之一。水溶性富勒烯C60衍生物特殊的理化性能赋予其多重独特的生物学活性，使其在神经退行性病变防治中显示出潜在的应用前景。然而，C60衍生物对小胶质细胞活化行为的影响及机制尚不清楚。本项目通过脂多糖（LPS）活化的小胶质细胞为体外模型，结合小胶质细胞活化介导的脑神经损伤体内模型，从分子、细胞及动物整体多层次、纵深探讨羟基或羧基化C60衍生物对活化小胶质细胞诱导的氧化应激及炎症反应的影响，阐明其对Nrf2/NF-κB炎症平衡体系的调控作用，以期揭示羟基或羧基化C60衍生物抑制活化小胶质细胞介导的神经组织变性的新机制。研究有望为脑神经退变性疾病的防治以及新型神经保护药物的开发提供科学依据。

本研究以细菌内毒素脂多糖、人源朊蛋白多肽等诱导建立了小胶质细胞活化及细胞氧化应激损伤模型，阐明了不同功能基团（如羟基、羧基及氨基）修饰的代表性水溶性富勒烯衍生物对小胶质细胞活化介导的脑神经组织炎性损伤的多靶点协同保护机制。研究发现，富勒烯衍生物通过调控线粒体动力、线粒体膜电位、氧化应激状态、抗氧化酶及MAPK信号途径多靶点机制，抑制小胶质细胞活化及其介导的炎性神经元细胞损伤；利用RNA干扰技术建立Nrf2基因缺陷细胞模型，证实了富勒烯衍生物是通过活化Nrf2/HO-1抗氧化系统，抑制NF-kB炎症途径作为细胞对抗小胶质细胞活化及细胞氧化应激损伤的重要机制，这一机制在过氧化氢诱导的体外细胞模型中得到了进一步证实。经脑内注射细菌内毒素脂多糖建立脑神经炎症损伤模型，通过对脑功能行为学评价、病理学观察、炎症诱导蛋白酶、及抗氧化抗炎蛋白酶的检测等，进一步明确了富勒烯衍生物对脑神经炎症性损伤的保护作用。总之，通过该项目研究为拓展功能化富勒烯衍生物在脑神经系统退行性炎症性疾病的治疗与预防中的应用提供科学理论依据，对促进新型神经保护药物的开发提供新的策略与思路。