In Vitro Tauopathy Model for Traumatic Brain Injury

 描述（由申请人提供）：在重复性轻度人类创伤性脑损伤（TBI）患者和单次严重TBI多年后患者的大脑中存在广泛的含tau蛋白的神经元缠结和A β斑块病理。该项目的总体目标是建立一种新的体外TBI模型，以阐明将机械神经元损伤与tau异常联系起来的细胞内途径。为了实现这一目标，我们将测试中心假设，即由机械力引起的神经元损伤导致tau蛋白过度磷酸化，从而诱导随后的tau蛋白错误定位和tau蛋白介导的突触缺陷。我们将追求两个具体目标：在目标1中，我们确定树突棘中机械损伤诱导的tau介导的形态缺陷的细胞机制。神经元将使用三种TBI方案进行拉伸，以模拟一种单一的严重TBI，重复的轻度损伤和炸弹爆炸波。我们将确定由拉伸方案引起的tau错误定位是否取决于tau过度磷酸化、tau激酶（CDK 5和GSK 3）的活化和A β寡聚体的产生。我们还将测试tau和Fyn在神经元损伤引起的脊柱丢失中的作用。在目标2中，我们将阐明机械损伤诱导的tau蛋白介导的树突棘功能缺陷的细胞机制。我们将在我们的体外模型中表征由机械损伤引起的突触前和/或突触后缺陷，并将确定这些缺陷是否由内源性tau蛋白、tau蛋白过度磷酸化、A β寡聚体的产生和钙调磷酸酶的激活介导。这将 成为第一个可以复制DAI和tau异常的体外TBI模型。使用这种新的模型，我们将在细胞水平上阐明TBI，AD和FTD之间的tau介导的联系，为TBI研究领域开辟了一个新的领域。

 DESCRIPTION (provided by applicant): Widespread tau-containing neurofibrillary tangles and A plaque pathologies are present in the brains of patients with repetitive mild human traumatic brain injuries (TBI) and of patients many years after a single severe TBI. The overall goal of the proposed project is to build a novel in vitro TBI model in order to clarify the intracellular pathways that link mechanical neuronal injuries to tau abnormalities. To achieve this goal, we will test the central hypothesis that neuronal injuries caused by mechanical forces lead to tau hyperphosphorylation, which induces subsequent tau mislocalization and tau-mediated synaptic deficits. We will pursue two Specific aims: In Aim 1, we determine the cellular mechanism underlying mechanical injury- induced tau-mediated morphological deficits in dendritic spines. Neurons will be stretched using three TBI protocols to mimic one single severe TBI, repeated mild injuries and bomb blast waves. We will determine whether the tau mislocalization caused by the stretching protocols depends upon tau hyperphosphorylation, activation of tau kinases (CDK5 and GSK3) and the production of A oligomers. We will also test the roles of tau and Fyn in spine loss caused by neuronal injuries. In Aim 2, we will clarify the cellular mechanism underlying mechanical injury-induced tau-mediated functional deficits in dendritic spines. We will characterize pre- and/or post-synaptic deficits caused by mechanical injuries in our in vitro model and will determine whether these deficits are mediated by endogenous tau, tau hyperphosphorylation, the production of A oligomers and the activation of calcineurin. This will be the first in vitro TBI model that can replicate DAI and tau abnormalities. Using this novel model, we will clarify the tau-mediated link between TBI, AD, and FTD at a cellular level, opening a new area to the field of TBI research.