Proteasome activation to protect the white matter in neonatal hypoxic-ischemic encephalopathy.

蛋白酶体激活保护新生儿缺氧缺血性脑病中的白质。

基本信息

批准号：
10028353
负责人：
Jennifer Kim Lee
金额：
$ 55.46万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2024-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10028353
关键词：
3-Dimensional Acute Adjuvant Adjuvant Therapy Affect Apoptosis Asphyxia Neonatorum Atrophic Axon Bioavailable Biochemistry Biology Blood gas Brain Brain Hypoxia-Ischemia Brain Injuries Cell Culture Techniques Cell Death Cell Differentiation process Cell Lineage Cell Maturation Cells Cellular biology Cerebrum Clinical Clinical Research Cognition Cognitive Cognitive deficits Data Dependovirus Dose Electrolytes Electron Microscopy Exhibits Failure Family suidae Genetic Glucose Goals Health Human Impairment Infant Injury Intravenous Magnetic Resonance Imaging Mediating Mediator of activation protein Methods Modeling Monitor Myelin Myelin Proteins Myelin Sheath Neonatal Neonatal Intensive Care Nervous System Trauma Neurocognitive Neurocognitive Deficit Neurologic Neurological outcome Neurons Newborn Infant Oligodendroglia Olives - dietary Outcome Oxidative Stress Oxides Oxygen Patients Pharmaceutical Preparations Physiological Processes Post-Translational Protein Processing Property Prosencephalon Proteasome Inhibition Proteasome Inhibitor Protein Biosynthesis Proteins Quality Control Recovery Regimen Regulation Resistance Rewarming Risk Role Sedation procedure Serotyping Small Interfering RNA Term Birth Testing Therapeutic Ubiquitination Ventilator Virus axon injury behavior test clinical care clinically relevant cohort cytokine cytotoxic deprivation disability experimental study functional outcomes hemodynamics hypoxia neonatorum improved knock-down mortality risk motor impairment multicatalytic endopeptidase complex myelination natural hypothermia neonatal death neonatal hypoxic-ischemic brain injury neonate neuropathology novel oligodendrocyte precursor oxidation oxidative damage postnatal precursor cell prenatal preservation protein degradation side effect small hairpin RNA small molecule small molecule inhibitor therapeutic target white matter white matter injury

项目摘要

Neonatal hypoxic-ischemic encephalopathy (HIE) from birth asphyxia causes persistent and severe neurologic disabilities, even in patients who receive therapeutic hypothermia. We found in clinical studies that white matter injury on MRI persists after hypothermic treatment. Thus, hypothermia is not fully protective. White matter injury is a prominent yet understudied component of the neurologic disabilities observed in neonates who receive hypothermia for HIE. Therapeutic adjuncts that protect the white matter might reduce the risk of permanent neurologic injury in HIE. Hypoxia-ischemia (HI) in neonatal pig, which has human-like white matter tracts, produces brain damage similar to that of full-term human newborns with HIE, including the white matter injuries observed in clinical studies. Our model includes clinically relevant whole-body hypothermia, rewarming at 0.5°C/h, sedation, continuous hemodynamic monitoring, ventilator support, and correction of blood gas and electrolyte abnormalities to mimic clinical neonatal intensive care. Preliminary data suggest that insufficient proteasome function mediates persistent white matter injury after HI and hypothermia. We postulate that white matter proteasome insufficiency causes a failure to clear oxidatively damaged proteins, causing oligodendrocyte apoptosis, potential disruption of oligodendrocyte precursor maturation, myelin and axonal injury, and white matter volume loss after HI and hypothermia. We will elucidate the proteasome’s role in white matter injury after whole-body HI and overnight hypothermia in neonatal swine. White matter injury and oligodendrocyte biology will be studied with neuropathology (including oligodendrocyte precursor maturation, stereology, cell death, and electron microscopy) and biochemistry (including protein post-translational modification and proteasome composition and activity) through 1 month recovery after HI. T- maze neurocognitive behavior testing with neuropathology correlation will provide a functional outcome. We developed new methods to genetically modulate proteasome activity in distinct, targeted regions of white matter in neonatal pig forebrain using virus-mediated enforced expression of a proteasome activator subunit or proteasome inhibition with short hairpin small interfering RNA. We will also use a small molecule proteasome inhibitor to determine whether proteasome inhibition aggravates white matter injury. Moreover, we will test the potential of the drug oleuropein to protect white matter. Oleuropein is a readily bioavailable compound with proteasome activating properties and few clinical side effects. An intravenous oleuropein dosing regimen will be used that protects oligodendrocytes and myelin, increases proteasome expression, and promotes clearance of oxidized proteins after HI and hypothermia. We will identify whether oleuropein acts on the standard proteasome or the immunoproteasome. Cultured human oligodendrocyte experiments will validate the proteasome as a therapeutic target and oleuropein’s actions after oxygen glucose deprivation. This project will advance the neonatal HI and cell biology fields by investigating novel mechanisms by which proteasome insufficiency mediates hypothermia-resistant injury in white matter. We will discover whether proteasome activation is a relevant therapeutic adjunct to hypothermia to protect white matter and improve neurologic outcomes in HIE.

新生儿缺氧缺血性脑病 (HIE) 出生时窒息会导致持续且严重的神经系统疾病即使在接受低温治疗的患者中，我们在临床研究中发现白质损伤。低温治疗后 MRI 仍然存在，因此，低温并不能完全保护白质损伤。在因 HIE 接受低温治疗的新生儿中观察到的神经系统疾病的组成部分尚未得到充分研究。保护白质的辅助治疗可能会降低 HIE 造成永久性神经损伤的风险。新生猪具有与人类相似的白质束，缺氧缺血（HI）会产生类似于人类的脑损伤患有 HIE 的足月人类新生儿的情况，包括我们的模型中观察到的白质损伤。包括临床相关的全身低温、每小时 0.5°C 的复温、镇静、持续血流动力学监测、呼吸机支持以及血气和电解质异常的纠正，以模拟临床新生儿重症监护的初步数据表明，蛋白酶体功能不足会介导持续性白质损伤。 HI 和体温过低后，我们假设白质蛋白酶体不足导致氧化清除失败。蛋白质受损，导致少突胶质细胞凋亡，少突胶质细胞前体成熟的潜在破坏， HI 和低温后髓磷脂和轴突损伤以及白质体积减少。我们将阐明蛋白酶体在全身HI和过夜低温后白质损伤中的作用新生猪的白质损伤和少突胶质细胞生物学将通过神经病理学进行研究（包括少突胶质细胞前体成熟、体视学、细胞死亡和电子显微镜）和生物化学（包括蛋白质翻译后修饰以及蛋白酶体组成和活性）到 HI 后 1 个月的恢复。我们开发的迷宫神经认知行为测试与神经病理学相关性将提供功能结果。基因调节新生猪白质不同目标区域蛋白酶体活性的新方法前脑使用病毒介导的蛋白酶体激活剂亚基的强制表达或蛋白酶体抑制我们还将使用小分子蛋白酶体抑制剂来确定是否存在短发夹小干扰RNA。此外，我们将测试橄榄苦苷药物的保护潜力。橄榄苦苷是一种易于生物利用的化合物，具有蛋白酶体激活特性，临床副作用很少。将使用静脉内橄榄苦苷给药方案来保护少突胶质细胞和髓鞘质，增加作用。蛋白酶体表达，并促进 HI 和低温后氧化蛋白的清除。橄榄苦苷作用于标准蛋白酶体或免疫蛋白酶体培养的人少突胶质细胞实验。将验证蛋白酶体作为治疗靶点以及橄榄苦苷在缺氧葡萄糖剥夺后的作用。该项目将通过研究蛋白酶体的新机制来推进新生儿 HI 和细胞生物学领域的发展。不足会介导白质的耐低温损伤。我们将发现蛋白酶体激活是否是一种机制。低温治疗的相关辅助治疗，可保护 HIE 中的白质并改善神经系统结果。