Manipulating N-acetyl-L-aspartate transport to treat Canavan leukodystrophy

操纵 N-乙酰基-L-天冬氨酸转运来治疗 Canavan 脑白质营养不良

基本信息

批准号：
10406711
负责人：
David E. Pleasure
金额：
$ 23.55万
依托单位：
UNIVERSITY OF CALIFORNIA AT DAVIS
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-02-01 至 2024-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10406711
关键词：
Ablation Acetyltransferase Affect Amino Acids Anticonvulsants Antisense Oligonucleotides Applications Grants Arachnoid mater Aspartoacylase Astrocytes Ataxia Autopsy Blindness Brain Brain Stem Canavan Disease Cell membrane Cells Cerebellum Cerebrospinal Fluid Child Citrates Cognitive deficits Coupled Data Development Drainage procedure Enzymes Epithelial Excretory function Genes Infant Kidney Knock-out Knockout Mice Lesion Ligase Lithium Lymphatic Endothelium Mediating Megalencephaly Meningeal Meninges Motor Mus Mutation N-acetylaspartate Neurodegenerative Disorders Neurologic Deficit Neurons Oligodendroglia Prosencephalon Reporting Route Seizures Sensory Sodium Specific qualifier value Testing Tubular formation Vacuole base brain magnetic resonance imaging cytotoxic dicarboxylate dicarboxylate-binding protein dietary manipulation effective therapy gene therapy human subject immunoreactivity knock-down leukodystrophy loss of function lymphatic vessel motor deficit mouse model prevent targeted treatment therapeutic target transcription factor urinary young adult

项目摘要

Canavan disease is a vacuolar (“spongiform”) leukodystrophy caused by ASPA mutations that diminish brain aspartoacylase activity. Current treatments for this neurodegenerative disorder, which include dietary manipulations, administration of lithium citrate and anticonvulsants, and AAV-mediated brain parenchymal ASPA gene therapy, do not reverse or prevent progression of neurological deficits in affected infants and children. Because aspartoacylase is necessary for cleavage of the abundant brain amino acid N-acetyl-L- aspartate (NAA), brain NAA is markedly elevated in Canavan disease. We were the first to report that knocking out or knocking down Nat8l, the gene that encodes the NAA-synthesizing enzyme N-acetytransferase 8-like, prevented development of motor deficits and brain vacuolation by aspartoacylase-deficient Canavan disease (“CD”) mice. Later, we showed that intrathecal administration of an Nat8l-inhibiting antisense oligonucleotide to young adult CD mice reversed their established brain NAA elevation, motor deficits and brain vacuolation. Together, those results strongly support the hypothesis that motor deficits and brain vacuolation in Canavan disease are consequences of elevated brain NAA. Our most recent studies, presented in this grant application, indicate that constitutive deletion of Slc13a3, which encodes NaDC3, a plasma membrane sodium-coupled transporter for NAA and other dicarboxylates, normalizes brain NAA content and prevents ataxia and brain vacuolation in CD mice. Also, we have confirmed prior reports that astroglia and renal proximal tubular epithelium express Slc13a3 and NaDC3, and have localized meningeal NaDC3 expression to arachnoid mater-associated Prox1+ cells. We now plan conditional deletion studies to determine whether selective ablation of NaDC3 from astroglia (Specific Aim 1), arachnoid (Specific Aim 2), or renal proximal tubular epithelium (Specific Aim 3) is sufficient to normalize brain NAA content and reverse motor deficits and brain vacuolation in symptomatic CD mice. Results of these studies will serve to guide development of selective Slc13a3 and NaDC3 therapeutic targeting strategies for infants and children with Canavan disease.

卡纳万病是一种由 ASPA 突变引起的空泡（“海绵状”）脑白质营养不良，减少大脑天冬氨酸酰化酶的活性，目前治疗这种神经退行性疾病的方法，其中包括饮食控制、服用柠檬酸锂和抗惊厥药，以及 AAV 介导的脑实质 ASPA 基因治疗，不会逆转或阻止进展受影响的婴儿和儿童的神经缺陷。因为天冬氨酸酰化酶对于裂解丰富的脑氨基酸 N-乙酰基-L- 是必需的天冬氨酸 (NAA)，卡纳万病中大脑 NAA 显着升高，我们是第一个报告的。敲除或敲低 Nat8l（编码 NAA 合成酶的基因） N-乙酰转移酶 8 样，通过以下方式预防运动缺陷和脑空泡形成的发展天冬氨酸酰基酶缺陷的卡纳万病（“CD”）小鼠后来，我们证明了鞘内注射。对年轻成年 CD 小鼠施用抑制 Nat8l 的反义寡核苷酸可逆转他们确定了大脑 NAA 升高、运动缺陷和大脑空泡化。结果强烈支持卡纳万运动缺陷和脑空泡化的假设疾病是大脑 NAA 升高的结果。我们在本拨款申请中提出的最新研究表明，组成性删除 Slc13a3，编码 NaDC3，NAA 的质膜钠偶联转运蛋白和其他二羧酸盐，使大脑 NAA 含量正常化，并防止共济失调和脑空泡形成此外，我们还证实了之前的报道，星形胶质细胞和肾近端小管。上皮表达 Slc13a3 和 NaDC3，并且脑膜局部表达 NaDC3 蛛网膜相关的 Prox1+ 细胞。我们现在计划条件删除研究，以确定 NaDC3 是否从星形胶质细胞（具体目标 1）、蛛网膜（具体目标 2）或肾近端肾小管上皮（具体目标 3）足以使大脑 NAA 含量正常化并逆转运动缺陷和大脑这些研究的结果将有助于指导有症状的 CD 小鼠的空泡形成。针对婴儿和儿童的选择性 Slc13a3 和 NaDC3 治疗靶向策略卡纳万病。