Treatment and Mechanisms of Diabetic Fracture Healing

项目描述/摘要 骨折愈合是糖尿病患者的一个重要健康问题，尽管胰岛素的可用性。 战略 由于成本、有效性和副作用的考虑，改善骨折愈合的方法还不发达。 初步数据表明，软骨细胞或软骨细胞中转录因子FOXO 1的谱系特异性缺失， 成骨细胞完全挽救糖尿病受损的骨折愈合组织学测量，通过microCT或 机械测试我们还确定了纤毛的谱系特异性损失，仅限于软骨细胞或 成骨细胞，干扰骨折愈合并模仿糖尿病骨折愈合。基于这些令人振奋的数据 我们已经设想了一种应用，其集中于FOXO 1和初级纤毛在软骨细胞中的作用， 成骨细胞是糖尿病患者骨折愈合不良的重要因素。因此，拟议的研究 将检验糖尿病导致FOXO 1上调以及伴随的下调和丢失的假设。 纤毛，这反过来又导致细胞特异性信号的损失，需要激活软骨细胞/成骨细胞， 从而导致骨折愈合不良。为了解决这一假设的治疗益处，我们 已经开发了一种可控制释放胰岛素样生长因子-1模拟物的水凝胶，称为 NFH-IGF。有两个具体目标。目的1将确定FOXO 1是否抑制纤毛发生和下游 糖尿病骨折中激活软骨细胞和成骨细胞愈合反应所需的信号通路 治愈具体机制将使用新开发的CyTOF技术和小鼠进行测试， 靶向缺失IFFT 80以抑制纤毛发生、缺失FOXO 1或双重缺失FOXO 1 + IFFT 80。目的 2将进一步开发一种新的装置，其具有控制释放具有IGF-1活性的模拟物， IGF（NFH-IGF）。目的是确定NFH-IGF治疗是否改善T1 DM和T2 DM糖尿病。 骨折愈合机制研究将确定NFH-IGF是否下调FOXO 1和上调FOXO 1， 软骨细胞和成骨细胞中的纤毛，以增强刺激这些细胞的细胞内信号传导途径。我们 我预计，拟议的研究不仅会导致新的知识纤毛在糖尿病骨折的作用， 而且还导致开发了一种用于治疗T1 DM和T2 DM的新型治疗辅助剂， 水凝胶-IGF制剂。

Project Description/Abstract Fracture healing is a significant health issue for patients with diabetes despite the availability of insulin. Strategies to improve fracture healing are underdeveloped due to concerns of costs, effectiveness and side-effects. Preliminary data demonstrate that lineage specific deletion of the transcription factor FOXO1 in chondrocytes or osteoblasts completely rescues diabetes impaired fracture healing measured histologically, by microCT or mechanical testing. We also determined that lineage specific loss of cilia, restricted to chondrocytes or osteoblasts, interferes with fracture healing and mimics diabetic fracture healing. Based on these exciting data we have conceived an application focusing on the role of FOXO1 and primary cilia in chondrocytes and osteoblasts as important contributing factors to deficient fracture healing in diabetics. Thus, the proposed studies will test the hypothesis that diabetes results in upregulation of FOXO1 and concomitant downregulation and loss of cilia, which in turn causes a loss of cell specific signaling needed to activate chondrocytes/osteoblasts and consequentially leading to deficient fracture healing. To address the therapeutic benefits of this hypothesis we have developed a nanofiber hydrogel with controlled release of an insulin-like growth factor-1 mimetic, called NFH-IGF. There are two Specific Aims. Aim 1 will determine if FOXO1 suppresses ciliogenesis and downstream signaling pathways needed to activate healing responses in chondrocytes and osteoblasts in diabetic fracture healing. Specific mechanisms will be tested using the newly developed CyTOF technology and mice with targeted deletions of IFT80 to inhibit ciliogenesis, deletion of FOXO1 or double deletion of FOXO1+IFT80. Aim 2 will further develop a novel device with controlled release of a mimetic with IGF-1 activity, nanofiber hydrogel- IGF (NFH-IGF). The goal is to determine whether NFH-IGF treatment improves T1DM and T2DM diabetic fracture healing. Mechanistic studies will determine whether NFH-IGF downregulates FOXO1 and upregulates cilia in chondrocytes and osteoblasts to enhance intracellular signaling pathways that stimulate these cells. We anticipate that proposed studies will not only result in new knowledge about the role of cilia in diabetic fracture healing but also result in the development in a novel therapeutic aid for the treatment of T1DM and T2DM using nanofiber hydrogel-IGF formulations.