miR-9调控FoxP2在甲基汞暴露致子代海马神经损伤中的作用及机制

Long-term mining and smelting activities in the Wanshan mercury mine area of Guizhou province have caused serious pollution to the local soil, atmosphere and water bodies, resulting in a higher risk of exposure to methylmercury in the local population. Exposure to methylmercury in pregnancy and lactation periods may induce brain injuries of filial generation, such as learning-memory dysfunction, cognitive disorder and language barrier which have confirmed by animal experiments and epidemiological studies. However, its mechanism is unknown, which is the bottleneck of early diagnosis and treatment. In order to investigate the possible mechanism of miR-9 and FoxP2 in learning-memory impairment induced by methylmercury, we use whole cell patch clamp technique combined with animal behavior experiment, Real-time PCR，Western-Blot，immunohistochemistry and cell transfection techniques, and the electrophysiological characteristic of VGCC and LTP in hippocampal neurons is our stduy target. The current study aims to further demonstrate the targeted regulation relationship of miR-9 and FoxP2 in hippocampal neuron damage through gain and loss-of-function approaches and provide novel therapeutic targets and strategies for early diagnosis and early treatment.

贵州省万山汞矿区长期的开采冶炼活动对当地土壤、大气和水体造成了严重的污染，当地居民存在较高的甲基汞暴露风险。动物实验和流行病学资料都已证实，妊娠期和哺乳期甲基汞暴露可造成子代学习记忆损伤、认知障碍、语言障碍等脑损伤，但其机制不明是制约临床早期诊断、早期治疗的瓶颈。本课题以海马神经元VGCC、LTP电生理特性为研究靶点，利用全细胞膜片钳结合动物行为学实验、Real-time PCR、Western-Blot、免疫组化、细胞转染等技术，探讨miR-9和FoxP2在甲基汞致子代学习记忆损伤中的作用机制。在此基础上构建过表达和抑制模型，进一步论证miR-9和FoxP2靶向调控关系在海马神经元损伤中的作用，以期为甲基汞暴露造成子代神经毒性的早诊断、早治疗提供新的靶标和思路。

动物实验和流行病学资料都已证实，生命早期是神经发育的关键时期，此时甲基汞暴露可造成子代学习记忆损伤，但其机制不明是制约临床早期诊断、早期治疗的瓶颈。基于此，本项目通过建立动物宫内甲基汞染毒及体外细胞实验模型，运用动物行为学、细胞生物学、分子生物学、形态学、电生理学等技术与方法多学科交叉结合，获得了以下主要结果：1. 发现了宫内甲基汞暴露对子鼠神经发育和学习记忆能力的影响。发现宫内甲基汞暴露可致大鼠总汞内负荷显著性升高；学习能力及空间记忆能力下降；形态学、超微结构、突触可塑性改变。2. 阐明了宫内甲基汞暴露对子鼠海马区蛋白组学的影响、miR-9和FOXP2表达情况，及其对甲基汞致子鼠突触相关蛋白的影响；3. 探讨并验证了甲基汞暴露对神经元miR-9和FOXP2以及其靶向调控关系，以及miR-9对甲基汞致神经元电生理特征和突触相关蛋白影响的调控作用；4. 发现并验证了甲基汞暴露对神经元损伤的潜在干预靶点及通路，并以此为基础揭示白藜芦醇的潜在值。本项目研究结果阐释了宫内甲基汞暴露对子代神经损伤的作用机制，为新时期针对性防治汞中毒健康损害及优化新的干预策略提供了科学依据。