MicroRNA mechanism and therapeutics of impaired wound healing

描述(申请人提供)：创面愈合受损导致的慢性创面，尤其是糖尿病患者和老年人，仍然是一个主要的未解决的生物医学挑战。这突显了研究受损伤口愈合的新机制并探索目前治疗方案的重要性和紧迫性。MicroRNAs(MiRNAs)是一类具有巨大生物学功能的新型非编码RNA。该项目的目标是确定miRNA损伤伤口愈合的机制和治疗方法。利用基于RCR的阵列和深度测序分析以及qRT-PCR，我们鉴定了一组在糖尿病和老年个体和小鼠骨髓来源的内皮祖细胞(EPC)中异常表达的miRNAs。其中，let-7、let-7b、let-7c、let-7d、let-7d*显著增加。该方案的假设是，让-7家族成员通过其靶基因在糖尿病和老年人内皮祖细胞功能受损和创面愈合障碍中发挥重要作用。通过let-7家族的调节剂对miRNA重新编程的“智能”内皮祖细胞可能代表着一种新的治疗慢性创伤的有效方法。我们将通过三个特定的目标来验证我们的假设：目标1将确定let-7家族成员在体外对内皮祖细胞迁移、增殖和凋亡的影响。目的2在体内研究let-7重编程的自体内皮祖细胞对糖尿病和老年小鼠创面血管生成和创面愈合的影响。目的3确定let-7介导的生物学效应的分子机制。Let-7家族通过内皮祖细胞的基因重编程在难治性创面中的生物学作用是一个未被探索的研究领域。这项拟议的研究将利用最新的细胞、分子和整体动物方法来瞄准尚未解决的主要生物医学挑战：慢性伤口。通过miRNAs在翻译水平上揭示创面愈合受损的分子机制和治疗方法，可能为慢性创面开辟新的科学范式。

DESCRIPTION (provided by applicant): Chronic wounds induced by the impaired wound healing especially in diabetic patients and aged individuals are still a major unsolved biomedical challenge. This has highlighted the importance and urgency of studying the novel mechanisms of the impaired wound healing and exploring now therapeutic options. MicroRNAs (miRNAs) have emerged as a novel class of noncoding RNAs with tremendous biological functions. The goals of this project are to determine the miRNA mechanism and therapeutics of impaired wound healing. Using RCR based array and deep-sequencing analysis as well as qRT-PCR, we identified a group of miRNAs that are aberrantly expressed in bone marrow (BM)-derived endothelial progenitor cells (EPCs) isolated from diabetic and aged individuals and mice. Among them, let-7 family members, let-7b, let-7c, let-7d, and let-7d* are significantly increased. The hypothesis of this proposal is that Let-7 family members play important roles in the impaired cellular functions of EPCs and impaired wound healing in diabetes and aged individuals via their target genes. miRNA-reprogrammed "smart" EPCs via modulators of let-7 family may represent a novel effective therapy for chronic wounds. We will test our hypothesis via three specific aims: Aim 1 will determine the effects of let-7 family members on the migration, proliferation and apoptosis of EPCs in vitro. Aim 2 will determine the effects of let-7-reprogrammed autologous EPCs on wound angiogenesis and wound healing in diabetic and aged mice in vivo. Aim 3 will determine the molecular mechanisms of let-7-mediated biological effects. The biological role of let-7 family on refractory wounds via gene reprogramming in EPCs is an unexplored research field. The proposed study will utilize the latest cellular, molecular, and whole animal approaches to target the major unsolved biomedical challenge: chronic wounds. Uncovering the novel molecular mechanisms and therapeutics of the impaired wound healing at translational level via miRNAs may open a new scientific paradigm in chronic wounds.