创伤相关miRNA筛选和功能研究

Skin wounds damage its barrier against environmental hazards, chronic non-healing wounds or excessive scarring lead to the decline in the quality of life and even life-threatening. MicroRNAs (miRNAs) are reported to be active regulator in various process, and that 30% of human genes are regulated by miRNAs. One miRNA can regulate the expression of multiple target genes, and genes involved in one physiological or pathological processes may be regulated by one or a few miRNAs. Thus, the miRNA is more suitable as therapeutic target than the traditional gene. Wound healing is a complex process that involves variety of cell types, various growth factors coordinate to control the wound healing. Is there one or more miRNAs play roles in the process of wound healing by coordinating a variety of cytokines? At present, little is known about miRNA that directly involved in wound healing. In this study, we will screening the wound inflammation, tissue formation and tissue reconstruction related miRNAs using miRNA array. Furthermore, we would explore the mechanism of selected miRNAs in the wound healing by the overexpression or loss of function experiments. This would supply molecular targets to the treatment of refractory wounds.

创伤导致皮肤屏障破坏，迁延不愈或瘢痕过度形成的伤口导致生活质量下降甚至威胁生命。MicroRNA（miRNA）在生命活动中具有广泛的调节功能，人类全部基因的30%受到miRNA的调控。一个miRNA可以调节多个靶基因的表达，在一个生理或病理过程中参与的所有基因有可能通过一个或少数几个miRNA来调节，因此miRNA作为疾病的治疗靶点比传统的基因更有优势。创伤愈合是一个多种细胞类型参与的复杂过程，各种生长因子相互协调，控制伤口愈合。那么在此过程中是否存在某种或某些miRNA通过协调多种细胞因子表达在伤口愈合过程中发挥作用？目前对于直接参与创伤愈合的miRNA知之甚少。本项目中我们将利用芯片筛选创伤炎性反应、组织形成及组织重建时期相关的miRNA，并通过功能获得或功能缺失实验对其在创伤愈合中的作用机制进行探讨，为难愈性创伤的治疗提供分子靶标。

创伤导致皮肤屏障破坏，迁延不愈或瘢痕过度形成的伤口导致生活质量下降甚至威胁生命。MicroRNA在生命活动中具有广泛而重要的调节功能，目前对于参与创伤愈合的miRNA知之甚少。本项目中我们利用芯片筛选出创伤炎性反应、组织形成及组织重建时期相关的miRNA，对其中表达量较高并且差异显著的11个差异miRNA进行了探针法real-time PCR验证，并进行靶基因的预测、验证、功能分析，发现其靶mRNA与创伤后巨噬细胞募集、M1型及M2型活化相关；对相应的mmu-mir-145-5p进行功能研究，发现其能够抑制巨噬细胞M1型分化，减少TNF-α和IL-6的分泌，促进巨噬细胞M2型分化，Arg-1表达升高。db-/-糖尿病小鼠中mmu-mir-145-5p表达异常导致巨噬细胞M2型分化不足引起小鼠创伤愈合速度减慢。该研究首次揭示了mmu-mir-145-5p调控巨噬细胞分化而调控创伤愈合速度，为难愈性创伤的治疗提供可能的分子靶标。