The role of smooth muscle PPAR gamma in neointima formation

平滑肌 PPAR γ 在新内膜形成中的作用

• 批准号: 8650309
• 负责人: Seth Bernat Furgeson
• 金额: $ 13.04万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-18 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8650309
• 关键词: 2,4-thiazolidinedione; Affect; Agonist; Alleles; Angioplasty; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Antineoplastic Agents; Arterial Injury; Atherosclerosis; Bexarotene; Blood Vessels; Bone Marrow; Bone Marrow Transplantation; CCL2 gene; Cell Proliferation; Cells; Cellular biology; Complication; Contractile Proteins; Data; Drug usage; Family; Galactosidase; Gene Expression; Gene Targeting; Genetic Transcription; Goals; Human; In Vitro; Inflammatory; Injury; Interleukin-6; Knock-out; Knockout Mice; Label; Ligands; Measures; Mediating; Mediator of activation protein; MicroRNAs; Modeling; Morbidity - disease rate; Mus; Nuclear Receptors; PPAR gamma; Peroxisome Proliferator-Activated Receptors; Phenotype; Pioglitazone; Process; Production; Proliferating; Publishing; RXR; Receptor Activation; Relative (related person); Reporter; Response Elements; Role; Signal Pathway; Site; Smooth Muscle; Smooth Muscle Myocytes; Stromal Cell-Derived Factor 1; Testing; Thiazolidinediones; Time; Tissues; Toxic effect; Vascular Diseases; activating transcription factor; base; cell motility; cell type; chemokine; cytokine; design; diabetic; effective therapy; femoral artery; in vivo; macrophage; member; migration; neointima formation; public health relevance; response; restenosis; rosiglitazone

DESCRIPTION (provided by applicant): PROJECT SUMMARY The goal of this project is to define the role of peroxisome proliferator-activated receptor (PPAR)3 activation in neointima formation. Neointima formation occurs frequently after angioplasty and causes significant morbidity; vascular smooth muscle cells (SMCs) are key cells during neointima formation. We will study the effects of two clinically available agents on SMC biology and neointima formation. PPAR3 is a ligand-activated nuclear receptor that has been shown to have beneficial effects on vascular disorders. We will compare the effects of two agents: pioglitazone (activates PPAR3 only) and bexarotene (an RXR agonist which activates PPAR3, PPAR1, PPAR4, LXR, and FXR). Our hypothesis is that PPAR3 activation specifically in smooth muscle cells (SMC) will reduce neointima formation by decreasing resident SMC migration and proliferation as well as SMC-derived chemokine production and subsequent recruitment of bone marrow-derived cells. We believe both pioglitazone and bexarotene will be effective but bexarotene may be more effective due to activation of other nuclear receptors. In Aim One, we will compare the effects of pioglitazone to bexarotene on SMCs. We will measure changes in proliferation, cytokine production, and smooth muscle gene expression. In Aim Two, we will determine if the agents affect levels of microRNAs crucial to maintaining SMC phenotype, such as miR- 143, miR-145, and miR-221. In Aim Three, we will examine the effects of the agents in vivo during femoral artery wire injury. To track recruitment of bone-marrow derived cells to the site of arterial injury, all mice will receive bone marrow transplants from a GFP positive donor. After wire injury, mice will be analyzed at multiple time points. Along with neointima size, we will measure production of chemokines (IL-6, MCP-1, SDF-11, and KC), recruitment of bone marrow-derived cells and macrophages, and cellular proliferation. We also plan to study the role of PPAR3 activation specifically in smooth muscle cells during neointima formation. Using an inducible tissue-specific knockout model, we will deplete PPAR3 in smooth muscle cells after mice have received bone marrow transplants from GFP positive donors. Inducible PPAR3 knockout mice and control mice will receive therapy with either pioglitazone, bexarotene or control and be subjected to femoral artery wire injury. At multiple time points, neointima size will again be measured. All mice used in Aim 3B will have the R26R reporter allele in which smooth muscle cells are labeled with 2-galactosidase. Since we can measure both bone marrow derived and resident SMCs, we will determine the relative contribution each cell type makes to the neointima. We will also be able to determine if PPAR3 specifically in smooth muscle cells mediates the effects of bexarotene or pioglitazone. PUBLIC HEALTH RELEVANCE: PROJECT NARRATIVE Bexarotene and pioglitazone are two clinically used drugs that activate PPAR3. In Aim One, we will test whether both agents can affect smooth muscle cell biology equally and, in Aim Two, we will determine whether the agents can change microRNA levels. In Aim Three, we will determine which agent can reduce neointima size the greatest after wire injury.

描述（由申请人提供）： 项目摘要 该项目的目标是确定过氧化物酶体增殖物激活受体 (PPAR)3 激活在新内膜形成中的作用。血管成形术后经常发生新内膜形成，并导致显着的发病率；血管平滑肌细胞（SMC）是新内膜形成过程中的关键细胞。我们将研究两种临床可用药物对 SMC 生物学和新内膜形成的影响。 PPAR3 是一种配体激活的核受体，已被证明对血管疾病具有有益作用。我们将比较两种药物的效果：吡格列酮（仅激活 PPAR3）和贝沙罗汀（一种 RXR 激动剂，激活 PPAR3、PPAR1、PPAR4、LXR 和 FXR）。我们的假设是，平滑肌细胞 (SMC) 中的 PPAR3 激活将通过减少驻留 SMC 迁移和增殖以及 SMC 衍生的趋化因子产生和随后骨髓衍生细胞的募集来减少新内膜形成。我们相信吡格列酮和贝沙罗汀均有效，但由于其他核受体的激活，贝沙罗汀可能更有效。在目标一中，我们将比较吡格列酮和贝沙罗汀对 SMC 的影响。我们将测量增殖、细胞因子产生和平滑肌基因表达的变化。在目标二中，我们将确定这些药物是否会影响对维持 SMC 表型至关重要的 microRNA（例如 miR-143、miR-145 和 miR-221）的水平。在目标三中，我们将检查股动脉线损伤期间药物在体内的作用。为了追踪骨髓来源细胞向动脉损伤部位的募集情况，所有小鼠都将接受来自 GFP 阳性供体的骨髓移植。金属丝损伤后，将在多个时间点对小鼠进行分析。除了新内膜大小外，我们还将测量趋化因子（IL-6、MCP-1、SDF-11 和 KC）的产生、骨髓源性细胞和巨噬细胞的募集以及细胞增殖。我们还计划研究 PPAR3 激活在新内膜形成过程中在平滑肌细胞中的作用。使用可诱导的组织特异性敲除模型，在小鼠接受 GFP 阳性供体的骨髓移植后，我们将耗尽平滑肌细胞中的 PPAR3。可诱导的 PPAR3 敲除小鼠和对照小鼠将接受吡格列酮、贝沙罗汀或对照的治疗，并遭受股动脉线损伤。在多个时间点，将再次测量新内膜尺寸。 Aim 3B 中使用的所有小鼠均具有 R26R 报告等位基因，其中平滑肌细胞用 2-半乳糖苷酶标记。由于我们可以测量骨髓来源的 SMC 和驻留的 SMC，因此我们将确定每种细胞类型对新内膜的相对贡献。我们还将能够确定平滑肌细胞中的 PPAR3 是否介导贝沙罗汀或吡格列酮的作用。 公共卫生相关性：项目叙述 贝沙罗汀和吡格列酮是两种临床使用的激活 PPAR3 的药物。在目标一中，我们将测试这两种药物是否可以同等地影响平滑肌细胞生物学，在目标二中，我们将确定这两种药物是否可以改变 microRNA 水平。在目标三中，我们将确定哪种药物可以最大程度地减少钢丝损伤后的新内膜尺寸。