Switch of Osteogenesis in Vascular Calcification

摘要 血管钙化的治疗进展可能会对公众产生深远的影响。血管钙化是一种 糖尿病的常见并发症伴随着发病率和死亡率的增加。尽管 确切的机制尚未确定，已知的血管钙化是一个活跃的过程，涉及 异位骨形成，其中成骨分化发生在从其他细胞转分化的细胞中 血统。以前的研究表明，血管内皮细胞改变细胞命运，分化为 血管钙化中的成骨样细胞。然而，目前尚不清楚是否可以通过诱导 成骨细胞-内皮细胞转分化可改善血管钙化。高级调查人员已经 表明小分子能够重新编程和调节细胞命运，还表明 内皮样细胞可以从其他谱系进行转分化。在目前的提案中，我们利用了 利用高通量技术鉴定旨在诱导成骨细胞-内皮细胞的小分子 并探讨其对糖尿病血管钙化的影响。在初步数据中， 我们使用高通量模型来确定GSK3抑制剂SB216763将成骨细胞转化为 内皮样细胞。我们发现SB216763或限制GSK3？调节Smad1和？的蛋白水平。 连环蛋白及其转录活性将成骨细胞的命运转变为内皮细胞分化。 此外，SB216763治疗减少EC来源的成骨分化，并减少钙化。 大鼠主动脉基质GLA蛋白缺失，建立血管钙化模型。治疗的方法 SB216763还可以减少糖尿病Ins2Akita/+小鼠的动脉钙化，而不影响其他组织。 因此，我们假设，抑制GSK3诱导成骨细胞-内皮转分化为 改善糖尿病患者的血管钙化。在具体目标1中，我们将阐明其机制。 抑制GSK3诱导的成骨细胞-内皮转分化。在具体目标2中，我们将 确定GSK3抑制是否改善糖尿病小鼠模型的血管钙化。如果成功，它将 建立成骨细胞-内皮细胞转分化的新概念，GSK3抑制剂SB216763可能 成为治疗获得性血管疾病钙化的一种新的治疗方法。

SUMMARY Therapeutic advances in vascular calcification may have far-reaching public benefits. Vascular calcification is a frequent complication of diabetes mellitus associated with the increase of morbidity and mortality. Although the precise mechanism has not been determined, vascular calcification is known to be an active process involving ectopic bone formation, in which osteogenic differentiation occurs in the cells transdifferentiated from other lineages. Previous studies have shown that vascular endothelial cells switch cell fate to differentiate into osteoblastic-like cells in vascular calcification. However, it is unknown if reversing this switch by inducing osteoblastic-endothelial transdifferentiation ameliorates vascular calcification. Advanced investigations have shown that the small molecules are able to reprogram and modulate cell fates, and also shown that endothelial-like cells can be transdifferentiated from other lineages. In present proposal, we take advantage of a small molecule identified by using high throughput technology, aiming to induce osteoblastic-endothelial transdifferentiation and investigate the effects on vascular calcification in diabetes mellitus. In preliminary data, we use a high throughput model to identify that GSK3 inhibitor SB216763 converts osteoblasts into endothelial-like cells. We show that SB216763 or limiting GSK3ß modulates protein levels of SMAD1 and ß- catenin and their transcriptional activity to switch the osteoblastic fate for endothelial differentiation. Furthermore, SB216763 treatment reduces EC-origin osteogenic differentiation and decreases calcification in aorta of matrix Gla protein null mouse, an established model of vascular calcification. The treatment of SB216763 also decreases arterial calcification in diabetic Ins2Akita/+ mice without affecting other tissues. Therefore, we hypothesize that GSK3 inhibition induces osteoblastic-endothelial transdifferentiation to ameliorate vascular calcification in diabetes mellitus. In specific Aim 1, we will elucidate the mechanism underlying osteoblastic-endothelial transdifferentiation induced by GSK3 inhibition. In specific Aim 2, we will determine if GSK3 inhibition ameliorates vascular calcification in diabetic mouse model. If successful, it will build osteoblastic-endothelial transdifferentiation as a new concept, and GSK3 inhibitor SB216763 may emerge as a new therapeutic approach to treat calcification in acquired vascular diseases.