High expression of VEGFA in MSCs promotes tendon-bone healing of rotator cuff tear via microRNA-205-5p.

Abstract

To explore the role of vascular endothelial growth factor A (VEGFA) in tendon-bone healing of rotator cuff tear (RCT) and to investigate its possible mechanism. Mesenchymal stem cells (MSCs) were transfected with pcDNA-VEGFA. The viability of MSCs was detected by cell counting kit-8 (CCK-8) assay. Expression levels of type I and type II collagen in MSCs were detected by quantitative Real time-polymerase chain reaction (qRT-PCR). RCT was constructed in rats. Meanwhile, all rats were divided into MSCs group and MSCs-pcDNA-VEGFA group, respectively. Biomechanical test was performed to detect ultimate load of failure and stiffness in RCT rats. Dual-luciferase reporter gene assay was conducted to analyze the binding condition between microRNA-205-5p and VEGFA, which was further verified by Western blot and qRT-PCR. VEGFA overexpression significantly promoted viability and proliferation of MSCs. Expression levels of type I and type II collagen were significantly upregulated after VEGFA overexpression in MSCs. Biomechanical test showed that VEGFA overexpression in RCT rats remarkably elevated ultimate load of failure and stiffness. Dual-luciferase reporter gene assay elucidated that VEGFA was the target gene of microRNA-205-5p. Furthermore, VEGFA negatively regulated microRNA-205-5p expression. VEGFA promotes tendon-bone healing of RCT via inhibiting microRNA-205-5p expression.