Role of LIPL-4 in lysosomal lipolysis and aging

LIPL-4 在溶酶体脂肪分解和衰老中的作用

• 批准号: 8676622
• 负责人: Louis Rene Lapierre
• 金额: $ 12.99万
• 依托单位: SANFORD BURNHAM PREBYS MEDICAL DISCOVERY INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-15 至 2014-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8676622
• 关键词: Acid Lipase; Address; Age of Onset; Aging; Alzheimer' s Disease; Alzheimer' s disease model; Animals; Autophagocytosis; Autophagosome; Biological Assay; Caenorhabditis elegans; Cell Culture Techniques; Cells; Chemicals; Cholesterol; Cholesterol Esters; Coupled; Data; Development; Disease; Disease model; Enzymes; Functional disorder; Genes; Genetic Screening; Grant; Homeostasis; Human; Hydrolysis; Impairment; Insulin; Lead; Learning; Link; Lipase; Lipids; Lipolysis; Longevity; Lysosomes; Mammalian Cell; Mediating; Metabolism; Methods; Microscopy; Modeling; Molecular; Mus; Nematoda; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Nutrient; Organelles; Organism; Paralysed; Pathway interactions; Pharmaceutical Preparations; Phase; Physiological; Process; Proteins; Proteomics; Publishing; Recycling; Reporter; Reporting; Research; Risk; Role; Scientist; Senile Plaques; Signal Pathway; Signal Transduction; Sirolimus; Site; Solutions; System; Testing; Therapeutic; Toxic effect; Translating; Vesicle; Work; Yeasts; age related; aging population; base; cholesterol trafficking; fly; high throughput screening; innovation; insulin signaling; lipid metabolism; new technology; novel; prevent; public health relevance; research study; sensor; skills; sterol esterase; therapeutic target; transcription factor

DESCRIPTION (provided by applicant): Dysfunctions in the utophagy/lysosomal pathway are pathologically significant in the development of age-related diseases, such as neurodegeneration. In C. elegans, several longevity models rely on increased autophagy for lifespan extension, suggesting a critical role for autophagy in aging. Animals can also enjoy longer lifespan when the nutrient-sensor TOR, a negative regulator of autophagy, is inhibited. Nonetheless, how autophagy mediates its beneficial effects is poorly understood. We recently reported that autophagy could be induced by over-expressing the putative lysosomal lipase LIPL-4, which resulted in a significant lifespan extension, enhanced lipolysis and altered TOR signaling, suggesting a link between lipid metabolism, autophagy and aging. LIPL-4 displays strong homology with human lysosomal acid lipase (LAL), a key enzyme in the hydrolysis of cholesterol via autophagy. Notably, impaired LAL-mediated cholesterol processing has been linked to the development of Alzheimer's disease. My new results show that over-expressing LIPL-4 ameliorates A¿ toxicity in a C. elegans model of Alzheimer's disease. Therefore, this proposal will test the hypothesis that LIPL-4, similar to LAL, mediates lysosomal lipid hydrolysis and will aim to elucidate how LIPL-4 modulates autophagy and mitigates A¿ toxicity. In Aim 1, I will confirm the intracellular site of action of LIPL-4 and determine its relationship to TOR signaling. In Aim 2, I will test whether LIPL-4 and LAL are functionally interchangeable in C. elegans. The mechanism of action by which LIPL-4 induces autophagy and modulates aging will also be elucidated. In Aim 3, I will investigate how LIPL-4 mediates a delay in the onset of Alzheimer's disease in C. elegans. I will also perform a high-throughput screen (HTS) to discover novel and specific candidate that activates LAL-mediated lipolysis, as a strategy against neurodegeneration. By determining the role of lysosomal lipolysis in aging, my proposal will provide a basis on which novel drugs can be discovered to prevent Alzheimer's disease. The 2-year postdoctoral K99 phase will consist in the characterization of the role of LIPL-4 in lysosomal function, lipid metabolism and aging. Cell-based assay reporter systems compatible with HTS will be used to find novel drugs to enhance LAL expression. The 3-year independent R00 phase will serve to further understand the role of LIPL-4 in lysosomal lipolysis, lipid signaling and aging and expand into studies on lipid dynamics, metabolism and proteostasis. Lead candidate activators of LAL will be validated using Alzheimer's disease model in C. elegans and cell culture models. This proposal includes cutting-edge approaches, such as proteomic analyses, CARS microscopy and HTS combined with the innovative use of disease models in C. elegans. In summary, the K99/R00 grant represents a unique opportunity for me to learn new technologies and develop my professional skills to successfully transition into an independent scientist in aging research.

描述（由申请方提供）：自噬/溶酶体途径中的功能障碍在年龄相关疾病（如神经变性）的发展中具有病理学意义。In C.在线虫中，一些长寿模型依赖于增加的自噬来延长寿命，这表明自噬在衰老中起着关键作用。当营养传感器TOR（一种自噬的负调节器）被抑制时，动物也可以享受更长的寿命。尽管如此，自噬如何介导其有益作用仍知之甚少。我们最近报道了自噬可以通过过度表达推定的溶酶体脂肪酶LIPL-4来诱导，这导致了显著的寿命延长、增强的脂解和改变的TOR信号传导，表明脂质代谢、自噬和衰老之间的联系。LIPL-4与人溶酶体酸性脂肪酶（LAL）具有很强的同源性，后者是通过自噬水解胆固醇的关键酶。值得注意的是，LAL介导的胆固醇加工受损与阿尔茨海默病的发展有关。我的新结果表明，过度表达LIPL-4可以改善C. elegans阿尔茨海默病模型。因此，该提案将测试LIPL-4类似于LAL介导溶酶体脂质水解的假设，并旨在阐明LIPL-4如何调节自噬并减轻A？毒性。在目标1中，我将确认LIPL-4的细胞内作用位点，并确定其与TOR信号传导的关系。在目标2中，我将测试LIPL-4和LAL在C中是否可以在功能上互换。优美的还将阐明LIPL-4诱导自噬和调节衰老的作用机制。在目标3中，我将研究LIPL-4如何介导阿尔茨海默病在C.优雅的我还将进行高通量筛选（HTS），以发现激活LAL介导的脂解的新的和特定的候选物，作为对抗神经变性的策略。通过确定溶酶体脂解在衰老中的作用，我的建议将为发现预防阿尔茨海默病的新药提供基础。 为期2年的博士后K99阶段将包括LIPL-4在溶酶体功能，脂质代谢和衰老中的作用的表征。与HTS相容的基于细胞的测定报告系统将用于寻找增强LAL表达的新药。为期3年的独立R 00阶段将有助于进一步了解LIPL-4在溶酶体脂解，脂质信号传导和衰老中的作用，并扩展到脂质动力学，代谢和蛋白质稳态的研究。将使用C. elegans和细胞培养模型。该提案包括尖端的方法，如蛋白质组学分析，汽车显微镜和HTS结合疾病模型在C。优雅的总而言之，K99/R 00补助金为我提供了一个独特的机会，让我学习新技术，发展我的专业技能，成功地转变为老龄化研究的独立科学家。