Metabolic regulation of fibroblast fate by ATP citrate lyase

ATP 柠檬酸裂解酶对成纤维细胞命运的代谢调节

• 批准号: 10441198
• 负责人: Samuel R Smith
• 金额: $ 3.9万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-12-01 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10441198
• 关键词: 5' -AMP-activated protein kinase; ATP Citrate (pro-S)-Lyase; Acetyl Coenzyme A; Acetylation; Actins; Aging; Apoptosis; Apoptotic; Automobile Driving; Biological Assay; Biological Availability; Bleomycin; CASP3 gene; Cell Aging; Cells; Chronic; Citrates; Collagen; Cre-LoxP; Cytolysis; Cytoplasm; Data; Data Set; Development; Diagnosis; Disease; Down-Regulation; Enzymes; Etiology; Exhibits; Extracellular Matrix; Extracellular Matrix Proteins; Fatty Acids; Fibroblasts; Fibronectins; Fibrosis; Fostering; Foundations; Gases; Genes; Genetic; Goals; Human; Impairment; In Vitro; Incidence; Investigation; Knock-out; Knockout Mice; Laboratories; Link; Lung; Lung diseases; Malignant Neoplasms; Measures; Mentorship; Messenger RNA; Metabolic; Metabolic Diseases; Mitochondria; Modeling; Molecular; Morbidity - disease rate; Mus; Myofibroblast; Pathogenicity; Pathway interactions; Patients; Phenotype; Phosphorylation; Population; Predisposition; Prevalence; Process; Production; Productivity; Proteins; Pulmonary Fibrosis; Reaction; Regulation; Research; Research Training; Resistance; Resolution; Respiratory Failure; Role; Route; Signal Transduction; Small Interfering RNA; Smooth Muscle; Solid; Source; Staurosporine; Stimulus; Testing; Therapeutic; Tissues; Western Blotting; acquired factor; age related; aged; airway remodeling; career; cell type; comparison control; fibrogenesis; fibrotic lung disease; human subject; idiopathic pulmonary fibrosis; in vivo; inhibitor; knock-down; lung injury; lung repair; mortality; mouse model; pharmacologic; pulmonary function; response; restoration; senescence; skills; therapeutic target; transcriptome sequencing; young adult

Project Summary Idiopathic Pulmonary Fibrosis (IPF) is a fibrotic lung disease characterized by progressive accumulation of fibrotic extracellular matrix (ECM) eventually leading to extensive airway remodeling, impaired lung function and respiratory failure. The cell type responsible for the majority of ECM production is an activated fibroblast known as the myofibroblast, characterized by α-SMA expression and production of ECM proteins, particularly collagen and fibronectin. Our laboratory has previously demonstrated that young mice are capable of spontaneously resolving bleomycin induced lung fibrosis, with the myofibroblast population undergoing apoptosis and clearance; in contrast, aged mice fail to resolve in association with a persistent myofibroblast population that appears to be resistant to apoptosis. ATP Citrate Lyase (ACLY) is an enzyme which catalyzes citrate to acetyl CoA conversion, thereby regulating acetyl-CoA bioavailability and fatty acid synthesis. Interrogation of a publicly available dataset indicates that ACLY mRNA levels are reduced in lungs of human subjects with IPF. Our preliminary data shows that ACLY expression in mice aged over 18 months is also deficient and that this expression decreases when subjected to bleomycin induced fibrogenesis. ACLY siRNA knockdown in IMR90 human fibroblasts promotes production of α-SMA, a myofibroblast marker, downregulates phosphorylation of AMPK and enhances myofibroblast apoptosis resistance. This project proposal will test the hypothesis that ACLY deficiency drives myofibroblast apoptosis regulation and determine whether ACLY is a therapeutic target in a mouse model of persistent lung fibrosis. Aim 1 will investigate ACLY regulation during myofibroblast differentiation, particularly its interaction with TGF-β1. Aim 2 will focus describing the mechanism of apoptotic regulation by ACLY, especially on its effects on AMPK phosphorylation. Aim 3 will make use of a genetic knockout mouse model to definitively examine whether ACLY deficiency is a key fibrotic driver capable of sustaining persistent fibrosis. Collectively these studies will elucidate the role ACLY in fibrogenesis and non-resolving persistent lung fibrosis while also serving as the vehicle for a solid foundation of research training for Samuel Smith (PI) under the mentorship of Dr. Victor Thannickal, fostering his professional development and facilitating his pathway to independent academic research.

项目摘要 特发性肺纤维化（IPF）是一种纤维化肺部疾病，其特征是进行性积累 纤维化细胞外基质（ECM）最终导致大量气道重塑，肺功能受损 和呼吸衰竭。负责大多数ECM生产的细胞类型是活化的成纤维细胞 称为肌纤维细胞，其特征是α-SMA表达和ECM蛋白的产生，特别是 胶原蛋白和纤连蛋白。我们的实验室以前已经证明，年轻小鼠能够 赞助解决博来霉素诱导肺纤维化，其中肌纤维细胞正在进行 凋亡和清除率；相比之下，老年小鼠与持续的肌纤维细胞结合了解决 似乎对凋亡具有抵抗力的人群。 ATP柠檬酸裂解酶（ACLY）是一种将柠檬酸酯催化至乙酰基CoA转化的酶 调节乙酰辅酶A的生物利用度和脂肪酸合成。询问公开可用的数据集 表明患有IPF的人类受试者的肺中伴有ACLY mRNA水平降低。我们的初步数据显示 在18个月以上的小鼠中，这种表达的表达也不足，当这种表达在 受到博来霉素诱导的纤维发生。 IMR90人类成纤维细胞中的Acly siRNA敲低促进 产生α-SMA，一种肌纤维细胞标记，下调AMPK的磷酸化并增强 肌纤维细胞凋亡抗性。该项目建议将检验以下假设： 肌纤维细胞细胞凋亡调节，并确定ACLY是否是小鼠模型中的治疗靶标 持续的肺纤维化。 AIM 1将在肌纤维细胞分化过程中研究ACLY调节，特别是 它与TGF-β1的相互作用。 AIM 2将重点描述Acly的凋亡调节机制 特别是它对AMPK磷酸化的影响。 AIM 3将利用遗传基因敲除鼠标模型 明确检查Acly缺乏是否是能够维持持续纤维化的关键纤维化驱动器。 这些研究总共阐明了在纤维发生和非分辨持续性肺纤维化中的作用 同时还为塞缪尔·史密斯（PI）的研究培训的稳固基础是 维克多·塔尼卡尔（Victor Thannickal 独立的学术研究。