应用斑马鱼模型研究丙戊酸钠经由P53/phlda3/ROS通路保护放射性脑损伤

Radiation-induced brain injury seriously affect the life quality of patients who suffer from brain tumors and there is no effective treatment at present. We have established a model of radiation-induced brain injury in zebrafish, and have found that sodium valproate has protective effect on radiation induced brain injury in vivo and in vitro because of the inhibition of oxidative stress reaction. Further experiments also revealed that p53 may target phlda3 on oxidative stress reaction to regulate radiation induced brain injury. And sodium valproate can affect the expression of P53 post irradiation. Therefore, based on our previous studies, we change the expression level of P53 and phlda3 in zebrafish and hippocampal neuronal cell line by constructing transgenic zebrafish, siRNA and RNA transfection, to observe the changes such as morphology of brain cells, behavior of zebrafish, cell radiosensitivity and ROS activity. Then we can determine whether P53/phlda3 regulate radiation induced brain injury through oxidative stress response, and whether sodium valproate protect radiation induced brain injury via P53/phlda3/ROS pathway. Finally, we will assess the protective effectiveness of valproate on radiation induced brain injury through clinical trials.

放射性脑损伤严重影响脑肿瘤患者生活质量且无有效防治药物。课题组前期建立了斑马鱼放射性脑损伤模型，通过体内、外实验发现丙戊酸钠具有良好的放射性脑损伤保护作用，且与其对氧化应激的调节相关。进一步的预实验还揭示P53可能通过靶向phlda3影响氧化应激反应从而调控放射性脑损伤，而丙戊酸钠的干预会影响照射后P53的表达。因此，我们在前期研究基础上，以斑马鱼模型及海马神经元细胞为研究载体，以氧化应激反应中P53及其下游调控因子phlda3为切入点，通过构建转基因鱼、RNA干扰、过表达等方法改变体内外模型P53/phlda3表达水平，利用斑马鱼行为学实验及分子生物学实验，分别从动物整体及细胞株水平研究P53/phlda3是否调控氧化应激反应引起的放射性脑损伤，以及丙戊酸钠是否经由P53/phlda3/ROS保护放射性脑损伤，并通过临床试验明确丙戊酸钠防治放射性脑损伤的临床应用价值。

放射性脑损伤严重影响脑肿瘤患者生活质量且无有效防治药物。课题组前期建立了斑马鱼放射性脑损伤模型，通过体内、外实验发现丙戊酸钠具有良好的放射性脑损伤保护作用，且与其对氧化应激的调节相关。我们在前期工作及芯片结果的基础上，继续观察P53突变型斑马鱼与野生型二者在照射后神经丘再生方面有无差异，进一步明确P53在神经放射损伤中的作用。并且采用芯片技术检测了照射后P53突变型斑马鱼及P53野生型斑马鱼脑组织中的mRNA基因表达谱改变，筛选P53相关放射性神经损伤的基因，并在斑马鱼模型以及在海马神经元细胞HT22中进行验证，并按照课题计划，对相关靶基因进行功能学实验。最后通过体内外实验探索铁坏死在放射性神经损伤中的发生及作用并初步探讨Nrf2及NCOA4对铁蛋白自噬及铁坏死的调控及其对神经元细胞放射损伤的调节。