Modulation of lysosomal function for the treatment of neuronal ceroid lipofuscino

描述（由申请人提供）：神经元蜡样脂褐素沉积症 (NCL) 是儿童时期最具破坏性的遗传性疾病之一，也是美国儿童神经变性的最常见原因。目前这些疾病无法治愈，治疗方法在很大程度上仍然是支持性的。 NCL 的特点是蜡质脂色素在溶酶体内逐渐积累；这种积累被认为是溶酶体代谢或运输缺陷造成的，但其本身也可能导致发病机制。我们假设增强清除过程将抵消 NCL 的疾病进展，即使主要缺陷仍未得到纠正。为了验证这一假设，我们将通过在两种 NCL 小鼠模型中使用清除过程的遗传 (Tfeb) 和化学 (海藻糖) 增强剂来增强溶酶体功能。在目标 1 中，我们将生成并表征转基因小鼠，这些小鼠有条件地表达转录因子 EB (TFEB) 的正常或组成型活性形式，转录因子 EB (TFEB) 是溶酶体和自噬途径的主要调节剂。我们还将进行分子遗传学分析，使我们能够绘制 TFEB 靶标组图谱，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，我们将这些转基因小鼠与 Cln3 ex7/8 和 Cln8mnd 小鼠（两种充分表征的 NCL 模型）杂交，以研究遗传 TFEB 增强对疾病过程的影响。重要的是，我们使用由两个不同基因突变引起的 NCL 模型来严格测试 TFEB 介导的清除是否确实可以减轻疾病，无论潜在的缺陷如何。在目标 3 中，我们将研究海藻糖的代谢，海藻糖是一种假定的自噬途径诱导剂，我们的数据表明它会激活 TFEB；我们将在两个 NCL 模型中测试海藻糖对病程的影响。该项目的结果将表明遗传或化学诱导的溶酶体增强是否能够抵消 NCL 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该领域的发展奠定基础 针对这些破坏性疾病的疗法。此外，从 NCL 研究中获得的任何知识原则上都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。 公共健康相关性：神经元蜡样脂褐素沉积症 (NCL) 是儿童期最具破坏性的遗传性疾病之一，也是美国儿童神经变性的最常见原因。拟议的工作将评估细胞清除的遗传和化学增强剂对抗 NCL 疾病进展的潜力，为这些疾病的治疗提供新的治疗途径。

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.