Modulation of lysosomal function for the treatment of neuronal ceroid lipofuscino

描述(申请人提供)：神经性蜡样脂褐素病(NCLS)是最具破坏性的儿童遗传性疾病之一，也是美国儿童神经变性的最常见原因。目前这些疾病尚无治愈方法，治疗仍在很大程度上是支持性的。NCLS的特点是脂类脂色素在溶酶体内的进行性积聚；这种积聚被认为是溶酶体代谢或运输缺陷的结果，但本身也可能参与发病。我们假设，加强清除过程将抑制NCLS的疾病进展，即使原始缺陷仍未得到纠正。为了验证这一假设，我们将在NCLS的两个小鼠模型中使用遗传(TFEB)和化学(海藻糖)清除过程的增强剂来提高溶酶体功能。在目标1中，我们将产生并鉴定有条件地表达正常或构成活性形式的转录因子EB(TFEB)的转基因小鼠，TFEB是溶酶体和自噬途径的主要调节器。我们还将进行分子遗传分析，使我们能够绘制TFEB目标组图，这是了解其在健康和疾病中的活动的关键一步。在目标2中，我们将这些转基因基因与Cln3EX7/8和Cln8mnd小鼠(两个NCLS的典型模型)进行杂交，以研究遗传TFEB增强对疾病进程的影响。重要的是，我们使用由两个不同基因突变引起的NCL模型，以严格测试TFEB介导的清除是否确实可以减轻疾病，而不考虑潜在的缺陷。在目标3中，我们将研究海藻糖的代谢，海藻糖是自噬途径的假定诱导者，我们的数据表明海藻糖激活了TFEB；我们将在两个NCL模型中测试海藻糖对疾病进程的影响。该项目的结果将表明，基因或化学诱导的溶酶体增强是否能够抵消NCLS的疾病进展，并影响受影响动物的健康和寿命。这项研究的积极成果将为发展 一种治疗这些破坏性疾病的方法。此外，从对NCLS的研究中获得的任何知识，原则上都可以适用于由溶酶体介导的细胞清除缺陷引起的其他神经退行性疾病。 公共卫生相关性：神经性蜡样脂褐素病(NCLS)是最具破坏性的儿童遗传性疾病之一，也是美国儿童神经变性的最常见原因。拟议的工作将评估遗传和化学增强剂对NCLS疾病进展的抑制作用，为治疗这些疾病提供新的治疗途径。

DESCRIPTION (provided by applicant): Neuronal ceroid lipofuscinoses (NCLs) are among the most devastating inherited disorders of childhood and the most common cause of neurodegeneration in children in the U.S. There is currently no cure for these disorders, and treatments remain largely supportive. NCLs are characterized by the progressive intralysosomal accumulation of ceroid lipopigment; this accumulation is thought to result from defects in lysosomal metabolism or trafficking, but could itself contribute to pathogenesis. We hypothesize that enhancing clearance processes will counteract disease progression in NCLs, even if the primary defect remains uncorrected. To test this hypothesis, we will boost lysosomal function by using genetic (Tfeb) and chemical (trehalose) enhancers of clearance processes in two mouse models of NCLs. In Aim 1 we will generate and characterize transgenic mice that conditionally express either a normal or constitutively active form of the transcription factor EB (TFEB), a master modulator of lysosomal and autophagic pathways. We will also perform molecular genetic analyses that will enable us to map the TFEB targetome, a crucial step in understanding its activities in health and disease. In Aim 2 we will cross these transgenics with Cln3 ex7/8 and Cln8mnd mice, two well-characterized models of NCLs, to investigate the effects of genetic TFEB enhancement on disease course. Importantly, we use models of NCL caused by mutations in two distinct genes in order to rigorously test whether TFEB- mediated clearance can indeed mitigate disease regardless of the underlying defect. In Aim 3 we will study the metabolism of trehalose, a putative inducer of autophagic pathways, which our data indicate activates TFEB; we will test the effect of trehalose on disease course in the two NCL models. Results from this project will show whether genetically or chemically induced lysosomal enhancement is able to counteract disease progression in NCLs and impact health and life span of affected animals. Positive results from this study will be the foundation for the development of a therapy for these devastating disorders. In addition, any knowledge gained from studies on NCLs could, in principle, be applicable to other neurodegenerative disorders caused by defects in lysosome-mediated cellular clearance. PUBLIC HEALTH RELEVANCE: Neuronal ceroid lipofuscinoses (NCLs) are among the most devastating inherited disorders of childhood and the most common cause of neurodegeneration in children in the U.S. The proposed work will assess the potential of genetic and chemical enhancers of cellular clearance to counteract disease progression in NCLs, providing new therapeutic avenues for the treatment of these disorders.