miR-5591靶向AGER/ROS/JNK抑制MSCs氧化应激损伤在糖尿病创面修复中的作用及机制

Diabetes chronic wounds don’t heal for a long time and is hard to treat. MSCs can promote wound repair, but have lower activity in diabetes patients. Our preliminary results showed that AGEs/AGER induced ROS accumulation, promoted JNK phosphorylation and resulted in MSCs oxidative injury. The biological information software showed that miR-5591 is the most likely microRNA within AGER 3 'UTR region for potential target sequence. AGEs treated MSCs transfected with miR-5591, AGER mRNA and protein level were down-regulated, p-JNK was inhibited. So, we suppose that miR-5591 inhibit AGER expression via combined with AGER 3 'UTR region, suppressing AGER/ROS/JNK signaling induced by AGEs, protecting MSCs antioxidative injury, improving MSCs biological activities and then promote diabetes chronic wounds healing.. This project will detect function and mechanism of miR-5591 target AGER/ROS/JNK signaling for diabetes chronic wounds repair by MSCs at cellular, molecular and animal levels, and will provide evidence for searching effective therapy for diabetes chronic wounds.

糖尿病创面长期不愈，治疗困难。MSCs可促进创面修复，但在糖尿病患者体内，MSCs生物活性低。申请者预实验发现，AGEs/AGER诱导MSCs中ROS堆积，促进JNK磷酸化，导致MSCs氧化应激损伤，降低其生物活性。生物信息软件分析发现，以AGER3'UTR区为潜在靶序列的microRNA中，miR-5591分值最高。用AGEs处理miR-5591转染过的MSCs，发现miR-5591显著抑制AGER mRNA及蛋白表达，同时降低JNK磷酸化。由此提出：miR-5591可通过靶向沉默AGER表达，拮抗AGEs激活的AGER/ROS/JNK信号通路，保护MSCs抗氧化应激损伤，提高其生物活性，利于糖尿病创面修复。 .本研究将从细胞、分子及动物水平研究miR-5591靶向AGER/ROS/JNK信号对MSCs修复糖尿病慢性创面的影响及分子机制；为探寻有效的糖尿病创面治疗方法提供理论依据。

AGEs/AGER信号轴可以触发ROS产生，激活下游信号通路诱导细胞凋亡。研究显示miRNAs可以调控ROS的产生和细胞凋亡。但是miRNAs在调节ADSCs修复糖尿病慢性创面中的作用及机制无人报道。该研究发现AGEs/AGER信号轴可以促进ADSCs细胞凋亡和ROS的产生。miR-5591通过直接靶向AGERmRNA的3'UTR区抑制其表达，从而抑制了AGEs/AGER信号轴，导致其下游JNK信号通路的激活收到抑制，导致ROS产生减少，细胞凋亡数量降低，促进了ADSCs修复糖尿病小鼠慢性创面。该研究为ADSCs修复糖尿病慢性创面的临床治疗提供了实验依据和基础。