丙烯酰胺突触损伤机理和脑源性神经营养因子保护作用的研究

Symptoms and signs induced by acrylamide (ACR) were similar as those of neurodegenerative diseases. Studies on molecular signaling and targets of ACR can provide scientific and technical evidences for prevention and treatment of neurodegenerative diseases. Based on the previous studies on the mechanisms of ACR's neurotoxicity and theory of tripartite synapses, the neurotoxic and protective cell and animal models of ACR were constructed in the present study facilitated by the theory and technology of toxicology and molecular biology. Functionally, the cascade reaction of phosphorylation sequence for synapsisnI in signal transduction pathway was detected to reveal the route of changes of synaptic plasticity; Structurally, the change of synapsinI and its influence on the binding and release with SNAREs after ACR exposure were measured to elucidate the effective targets of synaptic plasticity. Furthermore, the activation of RAS-MAPK signal transduction pathway via binding of BDNF with its receptors in gliocytes (Schwann cells)was conducted to explore the situ point of of synapsinI in signal pathway of BDNF in NB-1 cells. These results indicate the neuron-gliacyte combined action in the process of ACR neurotoxicity and protection, and provide the theoretical and technical support for better prevention and treatment of ACR occupational hazard and synapses mediated neurodegenerative diseases.

丙烯酰胺（ACR）不仅可以呈现与神经退行性疾病相似的表观症状和体征，而且其作用路径和效应靶点研究也可为神经退行性疾病的防治提供科学和技术线索。在前期ACR神经毒效应机制研究基础上和三重突触理论指导下，本项目运用毒理学和分子生物学理论和方法构建神经损伤和保护的细胞模型和动物模型，从功能上探讨突触素I磷酸化级联反应的信号传导通路，阐明突触可塑性的作用路径；从结构上说明ACR对突触素I构象变化及SNARE复合体结合和解离的影响，揭示突触可塑性的效应靶点；以突触的结构和功能可塑性变化为基点，进一步明确胶质细胞（施万细胞）中脑源性神经营养因子（BDNF）与其受体结合状态对神经元（NB-1）突触损伤效应路径的影响，找寻在体微环境中BDNF作用路径中突触素I结合位点。结果可以阐明神经元-胶质细胞联合作用网络在ACR损伤-保护中的科学基础，为ACR职业危害和突触介导的神经退行性疾病提供防治理论和技术支撑。

丙烯酰胺（ACR）不仅可以呈现与神经退行性疾病相似的表观症状和体征，而且其作用路径和效应靶点研究也可为神经退行性疾病的防治提供科学和技术线索。在前期ACR神经毒效应机制研究基础上和三重突触理论指导下，本项目运用毒理学和分子生物学理论和方法构建神经损伤和保护的细胞模型和动物模型，从功能上探讨突触素I磷酸化级联反应的信号传导通路，阐明突触可塑性的作用路径；从结构上说明ACR对突触素I构象变化及SNARE复合体结合和解离的影响，揭示突触可塑性的效应靶点；以突触的结构和功能可塑性变化为基点，进一步明确胶质细胞（施万细胞）中脑源性神经营养因子（BDNF）与其受体结合状态对神经元（NB-1）突触损伤效应路径的影响，找寻在体微环境中BDNF作用路径中突触素I结合位点。. 结果显示：1. 突触内特异性神经递质的传递和释放可能与P-Synapsin I/Synapsin I差异性表达所调控的SNARE复合体的解离状态导致的突触功能损伤相关；ACR导致NB-1细胞神经元突触损伤后，Synapsin I上游磷酸激酶MAPK、PKA和Ⅱ型Ca2+/CaM 依赖蛋白激酶的表达受到影响; 2. 受体TrkB对MAPK-ERK1/2具有一定的调节作用，外源性的BDNF干预后，受体TrkB表达增加，进而增加MAPK-ERK1/2表达，可能是其保护作用的机制之一; 3. ACR亚急性染毒可降低大脑皮层和小脑Synapsin I、P-Synapsin I的蛋白表达量，可能是导致AZD增加、NND增加、RRP囊泡分布比例降低的原因；ACR亚急性染毒可短时增加BDNF的蛋白表达水平以增强中枢神经系统的抗损伤能力，起到一定的保护作用。 确认了三重突触理论，即突触前膜、突触后膜及胶质细胞所形成的体内神经元微环境。建立神经元和血旺细胞共培养模型，在ACR神经元突触损伤和BDNF单一神经元损伤干预的数据基础上，进一步完善了BDNF对三重突触体系损伤干预的可能作用机理。. 本研究结论为神经元-胶质细胞联合作用网络在ACR损伤-保护中的科学基础，为ACR职业危害和突触介导的神经退行性疾病提供防治理论和技术支撑。