Evaluation of pigment epithelium derived factor and its derived peptide for bone healing

色素上皮衍生因子及其衍生肽对骨愈合的评价

基本信息

批准号：
10264787
负责人：
CHRISTOPHER NIYIBIZI
金额：
$ 17.3万
依托单位：
PENNSYLVANIA STATE UNIV HERSHEY MED CTR
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-15 至 2023-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10264787
关键词：
Acceleration Adult Affinity Allografting Amino Acids Angiogenesis Inhibitors Animal Model Autologous Transplantation BMP2 gene BMP7 gene Biomechanics Bone Morphogenetic Proteins Bone neoplasms Cells Cephalic Clinical Data Defect Development Diagnostic radiologic examination Evaluation Face Femoral Fractures Femur Forteo Fracture Fracture Healing Genes Greater sac of peritoneum Harvest Histologic Histology Impaired healing In Vitro Individual Injections Knock-out Knockout Mice Lead Mesenchymal Stem Cells Methods Minerals Morbidity - disease rate Mus Mutation Natural regeneration Osteoblasts Osteocytes Osteogenesis Osteogenesis Imperfecta Osteoid Pathology Patients Peptides Protocols documentation Reporting Saline Site Testing Tissue Harvesting Tissues Trauma Wild Type Mouse base bone bone healing disease transmission fetal healing microCT mineralization mouse model novel novel therapeutic intervention osteoblast differentiation pigment epithelium-derived factor pigment epithelium-derived factor receptor stem cell differentiation

项目摘要

Abstract The present exploratory application proposes to evaluate the use of two novel factors, Pigment epithelium derived factor (PEDF) and a 17 amino acid peptide derived from it (P17) for the acceleration of healing femur fractures created in serpinf1 knockout mice or wildtype mice. PEDF encoded by serpinf1 gene is synthesized by a wide variety of cells in fetal and adult tissues. Mutations in serpinf1 gene cause type VI osteogenesis imperfecta (OI) whose hallmark is excessive osteoid build up that fails to mineralize. Bone defects resulting from trauma, bone tumors, and cranial facial defects may heal but a large number of them result in delayed healing or nonunion. Autografts are usually used but there is a limited supply and tissue harvest may lead to donor site morbidity. Allografts can be used but there is potential for disease transmission. Bone morphogenetic proteins (BMPs) specifically, BMP-2 and BMP-7 have been approved for clinical use to augment bone fracture healing. BMPs are very expensive, their mode of application remains problematic and they are prone to inducing ectopic bone formation. We and others reported that PEDF promoted mesenchymal stem cell (MSCs) differentiation and increased osteoblast mineralization and reduced expression of Sost/Sclerostin by osteocytes. Preliminary data showed that P17, a peptide with affinity for PEDF-receptor promoted osteoblast differentiation, increased matrix mineralization in vitro, and suppressed Sost expression by osteocytes. P17 infused into serpinf1 knockout mice via the peritoneal cavity, increased stiffness of the femurs which were reported to possess reduced stiffness. We are thus proposing to explore whether PEDF or P17 possess ability to accelerate healing of delayed or nonunion bone fractures using two mice models. The global hypothesize is PEDF or the P17 peptide will accelerate healing of critical sized mouse femoral defects created in serpinf1 knockout mice or wildtype mice. PEDF possess antiangiogenic activity but the P17 peptide does not, the peptide may possess superior ability to accelerate healing and regeneration of murine femoral fractures. We will test the hypothesis through two aims. In aim 1, we will determine whether P17 or PEDF delivered via the peritoneal cavity will accelerate healing of femur fractures created in serpinf1 knockout mice. Critical sized fractures will be created in serpinf1 mice femurs; the mice will be injected with P17 or PEDF via peritoneal cavity. Control mice will be injected with saline. Some mice will be followed by radiographic analysis at weekly intervals to determine the extent of healing. At week 6, all mice will be sacrificed, femurs harvested and evaluated by histology, micro CT and biomechanical testing. In aim 2, similar approaches will be carried out but using wildtype mice. We predict that Both P17 and PEDF will accelerate healing of femur fractures in both mice models but P17 may be more effective because it does not possess antiangiogenic activity as PEDF. Completion of the exploratory studies will lead to the development of novel therapeutic approaches to treat bone fractures as well as other bone pathologies based on PEDF or PEDF-derived peptide or peptides. .

抽象的目前的探索性应用建议评估两种新因子的使用：色素上皮细胞衍生因子 (PEDF) 及其衍生的 17 个氨基酸肽 (P17)，用于加速股骨愈合 serpinf1 敲除小鼠或野生型小鼠产生的骨折。合成了serpinf1基因编码的PEDF 由胎儿和成人组织中的多种细胞产生。 serpinf1基因突变导致VI型成骨不完美症 (OI) 的特点是类骨质过度堆积且无法矿化。导致骨缺损外伤、骨肿瘤和颅面部缺损可能会痊愈，但其中很多会导致延迟愈合或不愈合。通常使用自体移植物，但供应有限，并且组织收获可能会导致供体部位发病率。可以使用同种异体移植物，但存在疾病传播的可能性。骨形态发生蛋白 (BMP)，特别是 BMP-2 和 BMP-7 已被批准用于临床增强骨折愈合。 BMP 非常昂贵，其应用方式仍然存在问题，并且它们容易诱发异位骨形成。我们和其他人报道 PEDF 促进间充质干细胞 (MSC) 分化和成骨细胞矿化增加以及成骨细胞表达减少骨细胞的 Sost/Sclerostin。初步数据显示，P17，一种对 PEDF 受体具有亲和力的肽促进成骨细胞分化，增加体外基质矿化，并抑制 Sost 表达由骨细胞。 P17通过腹膜腔注入serpinf1基因敲除小鼠体内，增加了腹膜的硬度据报道，股骨的刚度降低了。因此，我们建议探讨 PEDF 或使用两种小鼠模型，P17 具有加速延迟或骨不连骨折愈合的能力。这普遍的假设是 PEDF 或 P17 肽将加速小鼠股骨严重缺损的愈合在 serpinf1 敲除小鼠或野生型小鼠中创建。 PEDF 具有抗血管生成活性，但 P17 肽事实并非如此，该肽可能具有加速小鼠股骨愈合和再生的卓越能力骨折。我们将通过两个目标来检验该假设。在目标 1 中，我们将确定是 P17 还是 PEDF 通过腹膜腔递送将加速 serpinf1 基因敲除小鼠股骨骨折的愈合。 serpinf1 小鼠股骨将产生临界尺寸的骨折；小鼠将通过注射 P17 或 PEDF 腹膜腔。对照小鼠将被注射盐水。一些小鼠将进行放射学分析每周一次以确定愈合程度。第6周，处死所有小鼠，收获股骨并通过组织学、显微CT和生物力学测试进行评估。在目标 2 中，将采取类似的方法但使用野生型小鼠。我们预测 P17 和 PEDF 都将加速股骨骨折的愈合两种小鼠模型，但 P17 可能更有效，因为它不具有抗血管生成活性 PEDF。探索性研究的完成将导致新的治疗方法的开发基于 PEDF 或 PEDF 衍生肽治疗骨折以及其他骨病变。。