Purinergic Stimulation of Bone Regeneration

嘌呤能刺激骨再生

基本信息

批准号：
9269987
负责人：
BRUCE Neil CRONSTEIN
金额：
$ 53.64万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-06-01 至 2020-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9269987
关键词：
3-Dimensional 3D Print ADORA2A gene Adenine Nucleotides Adenosine Agonist Animal Model BMP2 gene Binding Biocompatible Materials Biological Blood Vessels Bone Growth Bone Morphogenetic Proteins Bone Regeneration Calcium Calvaria Cell Line Cell physiology Cells Ceramics Clinic Collagen Coupled Custom Cyclic AMP Defect Development Device Designs Dipyridamole Dose Endothelial Cells Extracellular Fluid Family Family member Formulation Fracture Fracture Healing G-Protein-Coupled Receptors Generations Goals Gold Growth Factor Half-Life Human Hydrolysis Hydroxyapatites Implant In Vitro Infection Inflammation Inflammatory Intravenous Knock-out Lead Liquid substance Measures Mediating Medical Mesenchymal Stem Cells Modeling Molecular Mus Natural regeneration Nuclear Translocation Oral Oryctolagus cuniculus Osteoblasts Osteoclasts Osteolysis Patients Pharmaceutical Preparations Pharmacology Porifera Prosthesis Purine Nucleosides Radial Receptor Signaling Recording of previous events Regulation Reporting Residual state Role Safety Signal Pathway Signal Transduction Signaling Molecule Site Source Stem cells Surface Testing Translating Translations Trauma Tumor Cell Invasion United States WNT Signaling Pathway angiogenesis bioactive ceramic bone bone healing bone metabolism cell type clinical practice clinically relevant design digital disability extracellular healing implantation improved in vivo inhibitor/antagonist knock-down long bone migration mouse model novel novel strategies public health relevance receptor repaired scaffold tripolyphosphate uptake vasculogenesis

项目摘要

DESCRIPTION (provided by applicant): Over 2 million long bone fractures are treated in the United States every year. Although most bone fractures heal spontaneously there is no "gold standard" for promoting bone regeneration in those settings in which either fractures do not heal or there is a critical sized segmental bone defect due to trauma or infection, devastating medical problems leading to significant disability. The recent development of custom printed biomaterial scaffolds that can fit and fill large bone defects may provide a novel solution and coating these scaffolds with agents designed to promote more rapid and complete bone healing may increase the efficacy of prosthetic scaffolds in healing segmental bone defects. Although currently used to promote bone generation, growth factors such as rh-BMP2 (BMP2) are of questionable efficacy and present significant safety issues. We have recently reported that adenosine A2A receptor (A2AR) stimulation increases osteoblast number and regulates osteoblast function in a murine model of inflammatory osteolysis and that A2AR stimulation diminishes osteoclast differentiation by inhibiting NF¿B activation and nuclear translocation. Moreover, A2ARs stimulate angiogenesis and vasculogenesis in vitro and in vivo. Thus, we propose to test the hypothesis that 3- dimensional printed scaffolds coated with an agent, dipyridamole, that increases local adenosine levels and indirectly stimulates A2ARs can further promote bone regeneration at critical sized segmental bone defects and to determine the cellular and molecular mechanisms for this phenomenon. We therefore propose the following aims: I. Development of coated bioactive ceramic scaffolds to treat critical segmental bone defects. We will determine whether implanting 3-dimensionally printed calcium triphosphate/hydroxyapatite scaffolds coated with dipyridamole, an agent which blocks cellular adenosine uptake and increases adenosine concentration in extracellular fluids, promotes bone regeneration in a rabbit radius model of segmental bone defect. We will further maximize scaffold design and dipyridamole dosing in vitro and in a murine calvaria model of bone regeneration. II. Determination of the cellular mechanism by which A2AR stimulation promotes bone regeneration. Using global and cell-selective knockouts of A2AR we will determine the cellular basis for A2AR-mediated bone regeneration in the murine calvaria model. III. Examination of the molecular mechanisms by which A2AR stimulation promotes bone regeneration in osteoblasts. We will test the hypothesis that A2AR signaling interacts with critical intracellular signaling cascades to promote bone regeneration using pharmacologic inhibitors of signaling pathways and by targeted knockdown of critical signaling molecules in primary cells and cell lines. The goals of this highly translational project are to establish the molecular and cellular basis for targeting A2ARs to stimulate bone regeneration and to rapidly translate these findings to the clinic.

描述（由适用提供）：每年在美国处理超过200万个长骨碎片。尽管大多数骨碎片愈合的赞助商都不是在那些分数无法愈合或由于创伤或感染引起的关键大小的分段骨缺损的情况下促进骨再生的“黄金标准”，这导致了严重的残疾。定制的生物材料支架的最新开发可以适合和填充大骨缺损，可能会提供一种新颖的解决方案，并与旨在促进更快和完整的骨骼愈合的试剂涂上这些脚手架，这可能会提高假体支架在愈合节段性骨骼缺陷中的有效性。尽管目前用于促进骨骼产生，但诸如RH-BMP2（BMP2）之类的生长因素具有可疑的有效性，并提出了重大的安全问题。我们最近报道说，腺苷A2A接收器（A2AR）刺激增加了成骨细胞的数量，并调节成骨细胞在炎症性溶解的鼠模型中，而A2AR刺激会通过抑制NF的激活和核转运来减少破骨细胞的分化。此外，A2AR在体外和体内刺激血管生成和血管生成。这是我们建议检验的假设：三维印刷支架涂有代理二吡啶胺，从而增加了局部腺苷水平并间接刺激A2ARS A2ARS可以进一步促进关键大小的段落缺陷的骨骼再生并确定该景色的细胞和分子机制。因此，我们提出以下目的：I。开发涂层的生物活性陶瓷支架以治疗关键的节骨缺损。我们将确定植入三维印刷的三磷酸钙/羟基磷灰石支架是否涂有二吡啶胺涂有二吡啶氨基，这种药物会阻止细胞腺苷摄取并增加细胞外流体中的腺苷浓度，从而促进分段骨骨骼缺陷模型中骨骼再生的骨再生。我们将进一步最大化脚手架设计和二吡啶胺的剂量，并在鼠类的鼠类再生模型中。 ii。 A2AR刺激促进骨再生的细胞机制的测定。使用A2AR的全局和细胞选择性敲除我们将确定鼠瓦尔瓦里亚模型中A2AR介导的骨再生的细胞基础。 iii。检查A2AR刺激促进成骨细胞中骨再生的分子机制的检查。我们将测试A2AR信号传导与关键细胞内信号传导级联相互作用的假设，以使用信号通路的药物抑制剂以及通过对原代细胞和细胞系中临界信号分子的靶向敲低进行靶向敲低来促进骨骼再生。这个高度翻译的项目的目标是建立靶向A2AR的分子和细胞基础，以刺激骨骼再生并迅速将这些发现转化为诊所。