Effects of ABCD1 deficiency on endothelial function and permeability to leukocytes in Cerebral X-linked Adrenoleukodystrophy

ABCD1 缺陷对脑 X 连锁肾上腺脑白质营养不良患者内皮功能和白细胞通透性的影响

• 批准号: 10249979
• 负责人: Patricia Leonor Musolino
• 金额: $ 39.48万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10249979
• 关键词: Acute; Address; Adhesions; Adrenoleukodystrophy; Affect; Age of Onset; Animal Model; Astrocytes; Binding; Biological; Biological Assay; Biological Models; Blood - brain barrier anatomy; Brain; Cell Adhesion Molecules; Cell model; Cells; Cerebrum; Cessation of life; Coculture Techniques; Code; Data; Defect; Demyelinations; Development; Disease; Disease model; Dose; Down-Regulation; Electrical Resistance; Endothelium; Event; Extravasation; Female; Functional disorder; Future; Gene Dosage; Gene Mutation; Gene Silencing; Gene Targeting; Genes; Genetic Transcription; Genotype; Heterozygote; Human; Impairment; Individual; Inflammatory; Inherited; Knowledge; Laboratories; Lead; Leukocytes; Maintenance; Mediating; Modeling; Molecular; Mutation; Pathway interactions; Patients; Penetrance; Pericytes; Permeability; Phenotype; Preventive; Preventive treatment; Proteins; Regulatory Pathway; Role; Signal Pathway; Stress; TGFB1 gene; Techniques; Testing; Tight Junctions; Toxic effect; Transcriptional Regulation; Vegetative States; Very Long Chain Fatty Acid; Viral; Work; base; blood-brain barrier disruption; blood-brain barrier function; blood-brain barrier permeabilization; brain endothelial cell; cerebral degeneration; cytokine; differential expression; early childhood; experimental study; imaging study; induced pluripotent stem cell; insight; junctional adhesion molecule; male; migration; mortality; nervous system disorder; neuroinflammation; novel; novel therapeutic intervention; peroxisome; prevent; promoter; small molecule; targeted treatment; tool; transcription factor; transcriptome sequencing

X-linked adrenoleukodystrophy (ALD) is a devastating neurologic disorder caused by mutations in the ABCD1 gene characterized by the accumulation of very long-chain fatty acids that affects 1:17,000 individuals in the U.S. Approximately 60% of male patients with ALD will convert to a devastating rapidly progressive form of inflammatory demyelination that leads to incapacitation or death within 2-3 years (cerebral ALD). Age of onset and phenotype varies even among individuals with the same mutation but a constant initial event in cerebral ALD is blood brain barrier (BBB) disruption with migration of leukocytes to the brain. The precise molecular and cellular mechanisms controlling BBB function during the course of ALD disease progress remain poorly understood given lack of cellular or animal models that faithfully recapitulate cerebral ALD. To address this critical knowledge gap, Dr. Musolino’s laboratory recently developed an ALD ex-vivo model system using gene-editing strategies and human brain microvascular endothelial cells. Dr. Musolino’s initial studies provide evidence that loss of ABCD1 directly impairs brain endothelial barrier integrity by increasing TGFβ1 levels in a manner correlated with severe transcriptional downregulation of Claudin 5 and increased permeability to small molecules. These alterations precede the accumulation of very-long chain fatty acids suggesting that the BBB dysfunction is not a direct consequence of their accumulation. As with patients, in addition to ABCD1 deficiency in this model, a second event, endothelial activation by inflammatory cytokines or flow sheer stress, is necessary to increase the permeability to leukocytes. Building upon these strong preliminary data Dr. Musolino’s hypothesizes that levels of ABCD1 expression in brain microvascular endothelium controls transcriptional regulation of tight junction proteins via TGFβ1-regulated pathways and determines the permeability to leukocytes during endothelial activation in a dose-dependent manner. To test this hypothesis Dr. Musolino will probe the effect of ABCD1 deficiency upon the BBB by (1) Identifying the molecular mechanisms governing tight junction disruption and increased permeability of ABCD1- deficient brain endothelium (Aim 1), (2) Determining functional consequences of downregulation of tight junction proteins and main regulatory pathways (Aim 2), and (3) Quantifying ABCD1 gene-dose effect on endothelial barrier function (Aim 3). Upon successful completion of these studies Dr. Musolino will have leverage the ability to model the impact of a single-gene mutation to unravel the mechanisms governing the traffic of cells across the BBB in ALD setting forth a strategy to identify the molecular and cell biological mechanisms underlying the conversion to cerebral disease, develop functional assays to test novel therapeutic approaches, and inform the field of neuroinflammation.

x连锁肾上腺脑白质营养不良症（ALD）是一种毁灭性的神经系统疾病，由肾上腺皮质蛋白的突变引起