ER stress and neonatal hypoxia ischemia encephalopathy

新生儿缺氧缺血（HI）是新生儿脑血流中断引起的损伤。它发生在 2-4 1000例足月分娩和60%的早产儿。它是死亡和发病的主要原因 与终生神经损伤有关。 内质网（ER）应激是HI后遇到的主要病理学，其与细胞凋亡的失调相关。 蛋白质折叠导致细胞凋亡和炎症。HI诱导的ER应激上调促凋亡蛋白的表达， 肌醇需要酶-1 α（IRE 1 α）信号通路，也与活性氧有关 (ROS)积累，主要来自NADPH依赖性细胞色素P450还原酶（NPR）和P450 2 E1 (CYP)复杂. ER抑制剂1（BI-1）蛋白表达于ER膜上，在抑制ER中起主要作用 应激诱导的信号通路。BI-1可以直接与IRE 1 α结合，从而抑制这种促凋亡途径， 以及通过解离NPR-NPR复合物来减少ROS积累。 本研究的目的是建立BI-1的抗凋亡和抗炎作用，在体外氧 葡萄糖剥夺（OGD）模型和体内新生HI大鼠模型中的作用，并阐明其机制 从而赋予其保护性能。我们的中心假设是（1）用Ad- TMBIM 6载体将改善OGD后的细胞活力，并有助于确定BI-s-1 s的主要途径;（2） 通过Ad-TMBIM 6注射，脑中BI-1蛋白的过表达将改善新生儿HI后的恢复 通过减少ER应激诱导的（a）通过抑制IRE 1 α信号通路和（B）神经元凋亡 通过NPR-ROS复合物的解离和随后的ROS的抑制来抑制神经炎症。具体目标1： 确定ER应激信号通路在抗凋亡和抗炎机制中的作用 在体外氧葡萄糖脱氢酶（OGD）模型中的BI-1的浓度。具体目标2：确定BI-1是否 在体内新生HI大鼠模型中，上调通过IRE 1 α信号通路发挥其抗凋亡作用。 具体目标3：研究BI-1过表达的抗炎作用和信号通路 参与体内新生HI大鼠模型。 该提案的长期目标是：1）将BI-1确立为ER应激的主要调节剂2）将BI-1确立为ER应激的主要调节剂3）将BI-1确立为ER应激的主要调节剂4）将BI-1确立为ER应激的主要调节剂5）将BI-1确立为ER应激的主要调节剂6）将BI-1确立为ER应激的主要调节剂7）将BI-1确立为ER应激的主要调节剂8）将BI- 新生儿HI后的信号通路; 3）为BI-1作为潜在的治疗靶点提供了基础。

Neonatal hypoxia ischemia (HI) is an injury to the neonatal brain caused by interrupted blood flow. It occurs in 2-4 of 1000 full-term births and 60% of premature infants. It is the leading cause of mortality and morbidity associated with life-long neurological impairments. Endoplasmic reticulum (ER) stress is a major pathology encountered after HI, associated with dysregulation of protein folding leading to apoptosis and inflammation. HI induced ER stress up regulates the pro-apoptotic Inositol requiring enzyme-1 alpha (IRE1α) signaling pathway and is also associated with reactive oxygen species (ROS) accumulation, mainly from the NADPH-dependent cytochrome P450 reductase (NPR) and P450 2E1 (CYP) complex. Bax-inhibitor 1 (BI-1) protein, expressed on ER membrane, has been shown to play a major role in inhibiting ER stress induced signaling pathways. BI-1 can directly bind to IRE1α thus inhibiting this pro-apoptotic pathway as well as reduce ROS accumulation by dissociating the NPR-CYP complex. The objective of this study is to establish BI-1s anti-apoptotic and anti-inflammatory effects in an in vitro oxygen glucose deprivation (OGD) model and in an in vivo neonatal HI rat model as well as to elucidate the mechanisms via which it confers its protective properties. Our central hypothesis is that (1) transfection of cells with Ad- TMBIM6 vector will improve cell viability after OGD as well as help determine BI-s-1s major pathways; (2) overexpression of the BI-1 protein in the brain, via Ad-TMBIM6 injection will improve recovery after neonatal HI by reducing ER stress induced (a) neuronal apoptosis via inhibition of IRE1α signaling pathway and (b) neuroinflammation via dissociation of the NPR-CYP complex and subsequent inhibition of ROS. Specific Aim 1: To determine the role of ER stress signaling pathways in the anti-apoptotic and anti-inflammatory mechanisms of BI-1 in an in vitro Oxygen Glucose Deprivation (OGD) model. Specific Aim 2: To determine whether BI-1 upregulation exerts its anti-apoptotic effects via the IRE1α signaling pathway in an in vivo neonatal HI rat model. Specific Aim 3: To investigate the anti-inflammatory effects of BI-1 overexpression and the signalling pathways involved in an in vivo neonatal HI rat model. The long-term goals of this proposal are to: 1) establish BI-1 as main regulator of ER stress 2) establish BI-1s signaling pathways after neonatal HI; 3) provide a basis for BI-1 as a potential therapeutic target.