权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Site-1 protease-mediated lipid metabolism in lymphatic vascular development

位点 1 蛋白酶介导的淋巴血管发育中的脂质代谢

基本信息

批准号：
10400114
负责人：
Lijun Xia
金额：
$ 43.7万
依托单位：
OKLAHOMA MEDICAL RESEARCH FOUNDATION
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10400114
关键词：
Address Anabolism Apoptosis Blood Blood Vessels Cardinal vein Cell membrane Cells Cellular Metabolic Process Cholesterol Cholesterol Homeostasis Complement Data Defect Development Diabetes Mellitus Dietary Fats Dorsal Embryonic Development Endothelial Cells Endothelium Exhibits Feedback Genes Genetic Transcription Glutamine Glycolysis Golgi Apparatus Human Immune Impairment Infection Inflammation Intercellular Fluid KDR gene Knowledge Lead Lipids Lymphangiogenesis Lymphatic Lymphatic Endothelial Cells Lymphatic Endothelium Lymphedema Malignant Neoplasms Mediating Membrane Metabolic Pathway Metabolism Modeling Mus Mutant Strains Mice Names Neoplasm Metastasis Obesity Operative Surgical Procedures Pathology Peptide Hydrolases Phenotype Physiological Primary Lymph Sac Process Proliferating Reporting Research Role SRE-2 binding protein Serine Protease Signal Transduction Site Skin Structure Testing Vascular Endothelial Growth Factor C Vascular Endothelial Growth Factor Receptor-3 Vascular System Wild Type Mouse absorption base cell growth cholesterol biosynthesis driving force early embryonic stage experimental study fatty acid oxidation immune function in vitro Assay in vivo inhibitor insight knock-down lipid metabolism lymphatic development lymphatic vasculature lymphatic vessel migration mouse development mutant novel novel therapeutics rapid growth receptor site-1 protease subcutaneous trafficking transcription factor tumor

项目摘要

The lymphatic vascular system is essential for transporting interstitial fluid, dietary fat, and immune cells. Defects in these functions contribute to lymphedema, impaired lipid absorption, obesity, abnormal immune function, and cancer metastasis. During embryonic development, lymphangiogenesis is robust, primarily driven by vascular endothelial growth factor C (VEGF-C)-mediated activation of VEGFR-3, a main VEGF-C receptor on lymphatic endothelial cells (LECs). Emerging evidence has shown the metabolism of endothelial cells is critical for vascular development. Changes in EC metabolic pathways are found in pathologies such as cancer and diabetes as well. But most research has been focused on blood endothelial metabolic pathways. Despite a few recent pioneering studies, knowledge of LEC metabolism during lymphangiogenesis is limited. There is an unmet need to bridge the knowledge gap between cellular metabolism and lymphatic vascular development. Site-1 protease (S1P), encoded by membrane-bound transcription factor peptidase, site 1 (MBTPS1), is a serine protease in the Golgi apparatus. S1P is a key regulator of cholesterol biosynthesis by proteolytic activation of a membrane-bound latent transcription factor, sterol-regulatory element binding protein 2 (SREBP2). Recently, we found that mice with inducible endothelial cell- specific deficiency of S1P (iEC Mbtps1-/-, Mbtps1f/f;;Cdh5CreERT2) exhibited severe subcutaneous lymphedema and defective lymphatic vasculature during development. Our pilot experiments also showed that mice with LEC-specific deficiency of SREBP2 (LEC Srebf2-/-, Srebf2f/f;;Lyve1Cre) had a similar lymphatic vascular defect during development. These strong in vivo preliminary data support the central hypothesis that S1P/SREBP2-mediated cholesterol biosynthesis is required for lymphatic vascular development. We will test the central hypothesis through two Aims: 1) determine whether lymphatic endothelial S1P/SREBP2- mediated cholesterol biosynthesis is required for lymphatic vascular development. We will characterize LEC cellular defects, such as differentiation, migration, and proliferation, of S1P or SREBP2-deficient mice at different stages of embryonic development. These in vivo analyses will be complemented by in vitro assays using LECs isolated from wild-type (WT) or mutant mice as well as primary human LECs;; 2) determine mechanisms by which S1P/SREBP2- mediated cholesterol biosynthesis regulate lymphangiogenesis. Based on our preliminary results, we will primarily test the hypothesis S1P/SREBP2-mediated cholesterol biosynthesis is required for sustained VEGFR3 signaling mainly by in vitro assays using WT or mutant LECs as well as human LECs with knockdown of S1P/SREBP2 or functional inhibitors to S1P and SREBP2. Based on strong preliminary data, our proposed study will reveal novel insights into roles of S1P-mediated lipid metabolism in lymphatic vascular development. Our study may lead to novel therapeutic opportunities for pathologies with lymphatic vascular defects.

淋巴管系统对于运输间质液、膳食脂肪和免疫细胞至关重要。缺陷这些功能导致水肿、脂质吸收受损、肥胖、免疫功能异常，在胚胎发育期间，淋巴管生成是稳健的，主要由血管生成驱动。内皮生长因子C（VEGF-C）-β介导的VEGF-C β 3活化，VEGF-C β 3是淋巴细胞上的主要VEGF-C β受体。新出现的证据表明，内皮细胞的代谢对血管内皮细胞的生长至关重要。发展。EC代谢途径的变化也在诸如癌症和糖尿病的病理中发现。但是大多数研究都集中在血液内皮代谢途径上。2尽管最近有一些开创性的研究，淋巴管生成过程中LEC代谢的知识是有限的。 S1 P是细胞代谢和淋巴管发育之间的间隙。膜结合转录因子肽酶，位点1（MBTPS 1），是高尔基体中的丝氨酸蛋白酶。胆固醇生物合成的关键调节因子，通过蛋白水解激活膜结合的潜在转录因子，最近，我们发现诱导型内皮细胞凋亡的小鼠， S1 P特异性缺陷（iEC Mbtps 1-CreERT 1/-CreERT 2，Mbtps 1f/f; iEC Cdh 5CreERT 2）表现出严重的皮下水肿，我们的初步实验还表明，具有LEC-1特异性的小鼠， SREBP 2缺陷（LEC Srebf 2-p53/-p53，Srebf 2f/f; p53 Lyve 1Cre）在治疗过程中也有类似的淋巴管缺陷。这些强有力的体内初步数据支持了S1 P/SREBP 2-β介导的主要假设，胆固醇的生物合成是淋巴管发育所必需的。我们将通过两个目的来检验中心假设：1）确定淋巴管内皮S1 P/SREBP 2-κ B是否与淋巴管内皮S1 P/SREBP 2-κ B的表达相关。淋巴管发育需要胆固醇介导的生物合成。我们将描述LEC细胞的特征， S1 P或SREBP 2-β缺陷小鼠在不同发育阶段的分化、迁移和增殖等缺陷。胚胎发育。这些体内分析将通过使用分离自野生型（WT）或突变型小鼠以及原代人LEC; 2）确定S1 P/SREBP 2-E2表达的机制。介导的胆固醇生物合成调节淋巴管生成。根据我们的初步结果，我们将主要检验S1 P/SREBP 2-β介导的胆固醇生物合成是持续的VEGFR 3信号传导所必需的假设主要通过使用WT或突变型LEC以及敲除S1 P/SREBP 2或 S1 P和SREBP 2的功能性抑制剂。基于强有力的初步数据，我们提出的研究将揭示新的见解S1 P-β介导的脂质的作用，我们的研究可能会导致新的治疗机会，淋巴管缺陷的病理学。