New approaches to combat CNS inflammation in Veterans: Targeting a metabolic enzyme in demyelinating disease

对抗退伍军人中枢神经系统炎症的新方法：针对脱髓鞘疾病中的代谢酶

• 批准号: 10084232
• 负责人: BRIAN A. ZABEL
• 金额: --
• 依托单位: VETERANS ADMIN PALO ALTO HEALTH CARE SYS
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10084232
• 关键词: Active Immunization; Acyl Coenzyme A; Acyltransferase; Affect; All-Trans-Retinol; American; Animal Model; Animals; Autoimmune; Automobile Driving; Blood; Brain; CD4 Positive T Lymphocytes; Cell physiology; Cells; Cellular biology; Clinical; Clinical Trials; Data; Demyelinating Diseases; Development; Diglycerides; Disease; Disease Progression; Enzymes; Esters; Experimental Autoimmune Encephalomyelitis; FOXP3 gene; Family; Goals; Health; Heterogeneity; Histology; Human; Immune; Immunosuppression; In Vitro; Incidence; Inflammation; Inflammatory; Injury; Interferon Type II; Interleukin-17; Knockout Mice; Lead; Lesion; Leukocytes; Lipid A; Lipids; Magnetic Resonance Imaging; Medical; Metabolic; Metabolic Pathway; Metabolism; Military Personnel; Molecular; Multiple Sclerosis; Mus; Myelin; Myelin Sheath; Neuraxis; Obesity associated disease; Onset of illness; Outcome; Pathogenesis; Pathogenicity; Pathology; Peptides; Persons; Pharmaceutical Preparations; Phase; Phase II Clinical Trials; Play; Population; Process; Regulatory T-Lymphocyte; Relapse; Research Project Grants; Retinoids; Risk; Role; Serum; Spinal Cord; Supplementation; Symptoms; T cell differentiation; T cell response; T-Cell Development; T-Lymphocyte; TNF gene; Testing; Therapeutic; Toxic effect; Triglycerides; Veterans; Vitamin A; autoreactivity; base; central nervous system demyelinating disorder; cohort; combat; cytokine; diacylglycerol O-acyltransferase; dietary manipulation; disorder risk; drug development; effector T cell; improved; in vivo; individual patient; inhibitor/antagonist; insight; interleukin-22; multiple sclerosis patient; multiple sclerosis treatment; novel; novel strategies; novel therapeutics; obesity treatment; oligodendrocyte-myelin glycoprotein; patient response; pre-clinical; prevent; response; safety study; selective expression; side effect; small molecule; tissue injury

Multiple sclerosis (MS) is a debilitating demyelinating disease of the central nervous system (CNS) that affects approximately 2.5 million people worldwide. US military personnel are at special risk to develop MS: the incidence rate in the US military population (12.9 per 100,000 person-years) is 1.7x higher than the civilian population, and 3x higher than the global population. Experimental autoimmune encephalomyelitis (EAE) is a widely studied animal model that shares many features of human MS. Tissue injury in EAE and MS is caused by inflammatory leukocytes that enter the CNS and destroy myelin. CNS-infiltrating, myelin-reactive CD4+ T cells play key roles in the pathology of MS. Although a number of MS treatments are available, due to the heterogeneity of the MS disease process, individual patient responses, and medication toxicities, there is a substantial unmet clinical need for improved therapeutics. T cell differentiation and function is profoundly affected by the engagement of metabolic pathways retinoid processing. Diacylglycerol O-acyltransferase-1 (DGAT1) is a metabolic enzyme that can catalyze the synthesis of triglycerides (TG, via DGAT activity), and retinyl esters (RE, via acyl CoA:retinol acyltransferase (ARAT) activity). Little is known regarding the role of DGAT1 in T cell biology. Our preliminary studies suggest that DGAT1 is selectively upregulated in activated mouse CD4+ T cells both in vitro and in vivo during EAE. DGAT1 is selectively expressed in brain lesions and CD4+ blood T cells obtained from MS patients. DGAT1 KO mice are protected against EAE, and DGAT1 pharmaco-inhibition suppresses EAE. Based on our preliminary data and the importance of retinoid metabolism in governing T cell differentiation and function, we hypothesize that T cell-expressed DGAT1 plays a key role in regulating pathogenic T cell activity in autoimmune demyelinating disease. In Aim 1 we will investigate the translational utility of targeting DGAT1 with small molecule antagonists to treat demyelinating disease. We will test the hypothesis that human blood CD4+ T cells express DGAT1 and contain DGAT/ARAT activity, and that DGAT1 regulates Treg and Th17 differentiation and function. We will also test the hypothesis that DGAT1 inhibitors administered after disease onset will reverse EAE progression and prevent relapse. Notably, small-molecule DGAT1 inhibitors are already being tested in clinical trials for treatment of obesity-associated diseases. Thus the studies in Aim 1 may uncover new MS-specific applications for existing drugs that have already cleared Phase I safety studies. In Aim 2 we propose to define the role of DGAT1 in CD4+ effector T cell formation and function. Using in vitro polarized CD4+ T cells, we will define DGAT1 expression and ARAT activity in mouse Treg and Th17 cells. Using naive T cells from WT and DGAT1 KO mice, we will define the role of DGAT1 in Treg and Th17 differentiation and function. To facilitate the study of DGAT1 in Treg development, we propose to generate DGAT1 KO/Foxp3/GFP mice (DGAT1 KO mice with GFP+ Tregs). In Aim 3, we propose to generate T cell conditional inducible DGAT1 KO mice (CD4CreERT2 -DGAT1fl/fl) to define the role of T cell-expressed DGAT1 in EAE. Finally, in Aim 4 we will investigate how dietary manipulation of vitamin A impacts the effects of DGAT1 deficiency in EAE. The results from this aim may provide a mechanistic rationale for vitamin A supplementation in MS, as low levels of vitamin A are associated with increased disease risk, and serum retinol levels are inversely correlated with magnetic resonance imaging outcomes in MS. Together, the proposed studies promise to elucidate novel insight into T cell immunometabolism and the role of DGAT1 in driving disease pathogenesis in MS, and holds great translational potential to reduce the impact of MS on US Veterans, their families, and the American public.

多发性硬化症(MS)是一种衰弱的中枢神经系统(CNS)脱髓鞘疾病 全球约有250万人受到影响。美国军事人员罹患多发性硬化症的风险特别高： 美国军人的发病率(12.9/10万人/年)是平民的1.7倍 人口，是全球人口的3倍。实验性自身免疫性脑脊髓炎(EAE)是一种 被广泛研究的动物模型与人类MS的许多特征相似，EAE和MS的组织损伤是由 通过炎性白细胞进入中枢神经系统并破坏髓鞘。中枢神经系统浸润性髓鞘反应性CD4+T细胞 细胞在多发性硬化症的病理中发挥着关键作用，尽管有许多多发性硬化症的治疗方法，由于 MS疾病过程、个体患者反应和药物毒性的异质性，存在 对改进的治疗方法的大量未满足的临床需求。 T细胞的分化和功能深受代谢途径维甲酸的影响 正在处理。二酰基甘油O-酰基转移酶-1(DGAT1)是一种代谢酶，可以催化 甘油三酯(TG，通过DGAT活性)和视黄酯(RE，通过酰基辅酶A：视黄醇酰基转移酶)的合成 (阿拉特)活动)。关于DGAT1在T细胞生物学中的作用，人们知之甚少。我们的初步研究表明 在EAE期间，DGAT1在体外和体内激活的小鼠CD4+T细胞中选择性上调。 DGAT1选择性表达于脑部病变和多发性硬化患者外周血中的CD4+T细胞。DGAT1 KO小鼠对EAE有保护作用，DGAT1药物抑制可抑制EAE。基于我们的 初步数据和维甲酸代谢在调节T细胞分化和功能中的重要性 假设T细胞表达的DGAT1在调节致病T细胞活性中起关键作用 自身免疫性脱髓鞘疾病。 在目标1中，我们将研究靶向DGAT1的小分子拮抗剂的翻译效用 治疗脱髓鞘疾病。我们将检验这一假设，即人类血液中的CD4+T细胞表达DGAT1和 包含DGAT/Arat活性，且DGAT1调节Treg和Th17分化和功能。我们会 同时测试在疾病发作后使用DGAT1抑制剂将逆转EAE进展的假设 并防止复发。值得注意的是，小分子DGAT1抑制剂已经在临床试验中进行测试 肥胖症相关疾病的治疗。因此，目标1中的研究可能会发现新的MS特异性 已通过第一阶段安全性研究的现有药物的申请。在目标2中，我们建议定义 DGAT1在CD4+效应T细胞形成和功能中的作用使用体外极化的CD4+T细胞，我们将 确定DGAT1在小鼠Treg和Th17细胞中的表达和Arat活性。使用来自WT和WT的幼稚T细胞 DGAT1KO小鼠，我们将明确DGAT1在Treg和Th17分化和功能中的作用。为了方便 DGAT1在Treg发育中的研究，我们建议建立DGAT1 KO/Foxp3/GFP小鼠(DGAT1 KO GFP+Tregs小鼠)。在目标3中，我们建议建立T细胞条件诱导型DGAT1 KO小鼠 (CD4CreERT2-DGAT1fl/fl)，以确定T细胞表达的DGAT1在EAE中的作用。最后，在目标4中，我们将 研究维生素A的饮食操作如何影响EAE中DGAT1缺乏的影响。结果是 这一目标可能为多发性硬化症患者补充维生素A提供一个机制上的理由，因为低水平的维生素 A与疾病风险增加有关，而血清视黄醇水平与磁感应强度呈负相关。 多发性硬化患者的磁共振成像结果。 总之，拟议的研究有望阐明对T细胞免疫代谢和 DGAT1在MS疾病发病机制中的作用，并具有巨大的翻译潜力，以减少 多发性硬化症对美国退伍军人、他们的家人和美国公众的影响。