MicroRNA-126 effects on free flap activity by regulating bone marrow mesenchymal stem cells

Chen Yong; Fan Long-kun

doi:10.3969/j.issn.2095-4344.2016.36.002

Abstract：BACKGROUND:MicroRNA has tissue and cel specificity, and high expression of endothelial cel-specific microRNA-126 (miR-126) plays an important role in angiogenesis. <br> OBJECTIVE:To explore the effect of miR-126 on transplanted free flap survival and histological activity as wel as its mechanism in angiogenesis. <br> METHODS:Transient transfection technology was used to enhance the expression of miR-126 in bone marrow mesenchymal stem cel s. Expression levels of macrophage inflammatory protein-1α, tumor necrosis factor-αand vascular cel adhesion molecule-1 mRNA were detected by real-time PCR, and expression levels of ERK1/2, AKT, pERK1/2, pAKT protein were measured by western blot assay. Forty-eight Sprague-Dawley rats were randomly divided into three groups (n=16 per group), fol owed by preparation of abdominal free flap models. Rats in the three groups were given injection of miR-126 mimics-transfected cel s, miR-126 mimics control-transfected cel s and PBS 1 cm and 3 cm distal to the free flap, respectively. <br> RESULTS AND CONCLUSION:Expression levels of macrophage inflammatory protein-1α, tumor necrosis factor-αand vascular cel adhesion molecule-1 mRNA in the cel s transfected with miR-126 mimics were decreased by 36, 3.5 and 14 times compared with those in the PBS group, respectively. Expressions levels of ERK1/2, AKT, pERK1/2, pAKT protein in the distal free flap increased significantly in the miR-126 mimics group than the other two groups, as did the ratios of pAKT/AKT and pERK1/2/ERK1/2. In addition, the expression levels of macrophage inflammatory protein-1α, tumor necrosis factor-αand vascular cel adhesion molecule-1 protein in the flap tissue fluid were significantly lower in the miR-126 mimics transfection group than the other two group. Al these findings suggest that miR-126 can promote free flap survival by creating favorable conditions for angiogenesis in the free flap tissue.