PDF(Pubmed)
Abstract：
Diabetes mellitus is a major cause of blindness and chronic ulcers in the working-age population worldwide. Wound healing is deeply dependent on neovascularization to restore blood flow. Former research has found that differentially expressed circular RNAs (circRNAs) are associated with hyperglycaemia-induced endothelial cell damage, and hypoxia-pretreated adipose-derived stem cells (ADSCs)-extracellular vesicle (HEV) transplants have a more therapeutic effect to enhance wound healing in diabetic mice by delivery circRNA. The current investigation employed high-throughput sequencing to identify circRNAs that are abnormally expressed between EV and HEV. The regulatory mechanism and predicted targets of one differentially expressed circRNA, circ-IGF1R, were investigated utilizing bioinformatics analyses, luciferase reporter assays, angiogenic differentiation assays, flow cytometric apoptosis analysis and RT-qPCR. Circ-IGF1R expression increased in HEV, and downregulation of circ-IGF1R suppressed and reversed the promotion effect of HEV on angiogenesis in ulcerated tissue. Bioinformatics analyses and luciferase reporter assays confirmed that miR-503-5p was the downstream target of circ-IGF1R, and inhibiting miR-503-5p restored the promotion effect of HEV on angiogenesis after circ-IGF1R silence. The study also found that miR-503-5p can interact with 3\'-UTR of both HK2 and VEGFA. Overexpression of HK2 or VEGFA restored the promotion effect of HExo on angiogenesis after circ-IGF1R silence. Overexpression miR-503-5p or silence HK2/VEGFA reversed the protective effect of circ-IGF1R to MLMECs angiogenic differentiation. Overexpression of circ-IGF1R increased the protective effect of HEV on the promotion of wound healing in mice with diabetes. Circ-IGF1R promotes HIF-1α expression through miR-503-5p sponging. Our data demonstrate that circ-IGF1R overexpression EVs from ADSCs suppress high glucose-induced endothelial cell damage by regulating miR-503-5p/HK2/VEGFA axis.
摘要：
糖尿病是全世界劳动年龄人群失明和慢性溃疡的主要原因。伤口愈合严重依赖于新生血管形成以恢复血流。以前的研究发现，差异表达的环状RNA（circRNAs）与高血糖诱导的内皮细胞损伤有关，和缺氧预处理的脂肪来源的干细胞（ADSC）-细胞外囊泡（HEV）移植具有更多的治疗效果，通过传递circRNA增强糖尿病小鼠的伤口愈合。当前的研究采用高通量测序来鉴定在EV和HEV之间异常表达的circRNAs。一种差异表达的circRNA的调控机制和预测的靶标，circ-IGF1R,利用生物信息学分析进行了调查，荧光素酶报告基因测定,血管生成分化试验，流式细胞仪凋亡分析和RT-qPCR。HEV中Circ-IGF1R表达增加，circ-IGF1R的下调抑制和逆转HEV对溃疡组织血管生成的促进作用。生物信息学分析和荧光素酶报告基因测定证实miR-503-5p是circ-IGF1R的下游靶标,抑制miR-503-5p可以恢复HEV沉默circ-IGF1R后对血管生成的促进作用。该研究还发现miR-503-5p可以与HK2和VEGFA的3'-UTR相互作用。过表达HK2或VEGFA恢复了HExo对circ-IGF1R沉默后血管生成的促进作用。过表达miR-503-5p或沉默HK2/VEGFA逆转了circ-IGF1R对MLMECs血管生成分化的保护作用。circ-IGF1R的过表达增加了HEV对糖尿病小鼠伤口愈合的保护作用。Circ-IGF1R通过miR-503-5p海绵作用促进HIF-1α表达。我们的数据表明，来自ADSC的circ-IGF1R过表达EV通过调节miR-503-5p/HK2/VEGFA轴来抑制高糖诱导的内皮细胞损伤。
