Autophagy and VSMC migration

自噬和 VSMC 迁移

基本信息

批准号：
9251904
负责人：
Zhonglin Xie
金额：
$ 67.56万
依托单位：
GEORGIA STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-04-01 至 2020-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9251904
关键词：
Acetylation Adenoviruses Amino Acids Angioplasty Animal Model Aorta Apolipoprotein E Arginine Atherosclerosis Autophagocytosis Basic Science Biological Assay Biomedical Research Blood Vessels Bypass Cardiac Myocytes Carotid Artery Injuries Cell Cycle Cultured Cells Data Development Diabetes Mellitus Diabetic Angiopathies Diet Event Exhibits Extracellular Matrix Fluorescence Foundations Gene Silencing Genetic Suppression Goals High Fat Diet Hyperplasia Hypertension In Vitro Injury Ligation Light Lysine MAP1 Microtubule-Associated Protein Mediating Microtubule Stabilization Microtubules Molecular Mus Muscle Cells Muscle function Operative Surgical Procedures Pathway interactions Pharmacology Platelet-Derived Growth Factor Prevention Process Protein Biosynthesis Proteins Role Skeletal Muscle Small Interfering RNA Smooth Muscle Smooth Muscle Myocytes Stents Testing Therapeutic Intervention Transcriptional Activation Transgenic Mice Vascular Diseases Vascular Proliferation Vascular Smooth Muscle Vascular remodeling Wound Healing alpha Tubulin base directional cell graft failure histone acetyltransferase in vivo insight loss of function migration novel oxidized lipid prevent public health relevance response restenosis tool vascular smooth muscle cell migration

项目摘要

DESCRIPTION (provided by applicant): In response to pro-atherosclerotic factors such as oxidized lipids, or to therapeutic interventions such as angioplasty, stents, or bypass surgery, vascular smooth muscle cells (VSMC) migrate to the intima, resulting in intimal hyperplasia, restenosis, graft failure, or atherosclerosis. Understanding the mechanisms involved in VSMC migration has been a major focus of biomedical research. Our exciting preliminary data show that in response to or wire-mediated carotid artery injury, increased expression of autophagy-related (Atg) proteins is associated with increased VSMC migration and intimal hyperplasia. Pharmacological and genetic suppression of autophagy inhibits VSMC migration. Mechanistically, suppression of vascular autophagy leads to the accumulation of amino acid synthesis protein 5 (GCN5), a ubiquitous histone acetyltransferase (HAT) that promotes transcriptional activation. Furthermore, we found that GCN5 accumulation is associated with increased α-tubulin acetylation, microtubule stabilization, and inhibition of VSMC migration. The central hypothesis is that autophagy-dependent degradation of GCN5 promotes VSMC migration via inhibition of α-tubulin acetylation. This hypothesis will be tested using gain-/lossof-function strategies in both animal models and cultured cells. Aim 1 will determine the role of autophagy in regulating VSMC migration in response to vascular injury in vivo by characterizing the spatial and temporal dynamics of vascular autophagy, VSMC migration, and neointimal hyperplasia using smMHC/eGFP transgenic mice, determining whether autophagy deficiency inhibits VSMC migration and neointimal formation in response to carotid ligation and/or vascular injury using Beclin1 heterozygous mice (beclin1+/-), and examining whether enhanced VSMC autophagy promotes VSMC migration and exacerbates neointimal hyperplasia and atherosclerosis in response to vascular injury in Atg7 SMC-specific transgenic mice (Atg-TG). In addition, the role of autophagy in regulating VSMC migration will be determined using gain- and loss-of-function approaches in cultured aortic rings and VSMCs. Aim 2 is to delineate the mechanism by which autophagy promotes VSMC migration. By test the hypothesis that autophagy promotes VSMC migration by enhancing GCN5 degradation and reducing α-tubulin acetylation. The proposed study will characterize the molecular mechanism by which autophagy degrades GCN5 in VSMCs, examine whether GCN5 acetylates α-tubulin and stabilizes microtubules, and determine whether autophagy suppression inhibits VSMC migration by increasing GCN5-mediated acetylation of α-tubulin in beclin+/- mice of wire-mediated carotid artery injury, carotid ligation, and atherosclerosis, and Apoe-/-/beclin1+/- mice fed with a high-ft diet.

描述（由适用提供）：响应诸如氧化的脂质等促动肌肉因子，或治疗性干预措施，例如血管成形术，支架或旁路手术，血管平滑肌细胞（VSMC）迁移到内膜，导致内膜，内膜增生，再融化，移植物，移植物，或Atherosssis。了解VSMC迁移涉及的机制一直是生物医学研究的主要重点。我们令人兴奋的初步数据表明，在响应或电线介导的颈动脉损伤时，自噬相关（ATG）蛋白的表达增加与VSMC迁移和内膜增生的增加有关。自噬的药理和遗传抑制抑制VSMC迁移。从机械上讲，血管自噬的抑制会导致氨基酸合成蛋白5（GCN5）的积累，这是一种无处不在的组蛋白乙酰转移酶（HAT），可促进转录激活。此外，我们发现GCN5的积累与α-微管蛋白乙酰化，微管稳定和VSMC迁移的抑制有关。中心假设是GCN5的自噬依赖性降解通过抑制α-微管蛋白乙酰化促进VSMC迁移。该假设将在动物模型和培养细胞中使用增益/丧失功能策略进行检验。 Aim 1 will determine the role of autophagy in controlling VSMC migration in response to vascular injury in vivo by characterizing the spatial and temporary dynamics of vascular autophagy, VSMC migration, and neointimal hyperplasia using smMHC/eGFP transgenic mice, determining whether autophagy deficiency inhibits VSMC migration and neointimal formation in response to carotid ligation使用Beclin1杂合小鼠（Beclin1 +/-）使用血管损伤，并检查增强的VSMC自噬是否促进了VSMC迁移，并加剧了ATG7 SMC SMC特异性转基因小鼠（ATGG-TG）的血管损伤的新膜增生和动脉粥样硬化。此外，将使用培养的主动脉环和VSMC中的功能丧失方法来确定自噬在确定VSMC迁移中的作用。目的2是描述自噬促进VSMC迁移的机制。通过测试自噬通过增强GCN5降解并减少α-微管蛋白乙酰化来促进VSMC迁移的假设。 The proposed study will characterize the molecular mechanism by which autophagy degrades GCN5 in VSMCs, examin whether GCN5 acetylates α-tubulin and stabilizes microtubulins, and determine whether autophagy suppression inhibits VSMC migration by increasing GCN5-mediated acetylation of α-tubulin in beclin+/- mice of wire-mediated carotid artery损伤，颈动脉连接和动脉粥样硬化，以及用高FFT饮食喂养的APOE - / - /beclin1 +/-小鼠。