METHODS: In vitro hydrogen peroxide (H2O2)-treated human keratinocyte (HaCaT) cell lines and in vivo animal wound models were established for this purpose. The cell migration was assessed using transwell and wound healing assays, while exosome biomarker expressions were studied using western blot. Moreover, adipose stem cells were identified using flow cytometry, alizarin red S and oil red O staining, and transmission electron microscopy.
RESULTS: Results indicated that H2O2 treatment inhibited the cell viability and migration of HaCaT cells while being promoted by ADSC-exos. Mechanistic investigations revealed that microRNA-let-7i-5p (let-7i-5p) in ADSC-exos was carried into the HaCaT cells, inhibiting the expression of growth arrest-specific-7 (GAS7). Rescue experiments further verified these results, which indicated that GAS7 overexpression reversed the effect of let-7i-5p on the viability and migration of HaCaT cells, suggesting ADSC-exos promoted wound healing via the let-7i-5p/GAS7 axis.
CONCLUSIONS: Adipose stem cell-derived-exos enhanced the viability and migration of HaCaT via carrying let-7i-5p and targeting GAS7, ultimately promoting wound healing in rats.
方法:为此目的建立了体外过氧化氢(H2O2)处理的人角质形成细胞(HaCaT)细胞系和体内动物伤口模型。使用transwell和伤口愈合试验评估细胞迁移,而外泌体生物标志物的表达使用蛋白质印迹研究。此外,使用流式细胞术鉴定脂肪干细胞,茜素红S和油红O染色,和透射电子显微镜。
结果:结果表明,H2O2处理抑制了HaCaT细胞的活力和迁移,同时受到ADSC-exos的促进。机制研究表明,ADSC-exos中的microRNA-let-7i-5p(let-7i-5p)被带入HaCaT细胞,抑制生长停滞特异性-7(GAS7)的表达。救援实验进一步验证了这些结果,这表明GAS7过表达逆转了let-7i-5p对HaCaT细胞活力和迁移的影响,提示ADSC-exos通过let-7i-5p/GAS7轴促进伤口愈合。
结论:脂肪干细胞来源的exos通过携带let-7i-5p和靶向GAS7增强HaCaT的活力和迁移,最终促进大鼠伤口愈合。