MiR-503 promotes wound healing of diabetic foot ulcer by targeting FBN1

Objective: To highlight the relationship between miR-503 and wound healing of diabetic foot ulcer (DFU). Methods: Microarray analysis was used to detect the dysregulated miRNAs between the DFU tissues and normal tissues. The expression of miR-503 in tissues and serum of patients with DFU was detected by qRT-PCR technique. Then, CCK-8 assay was applied to determine the cell proliferation. TUNEL assay was used for assessing the apoptosis of cells after treatment with miR-503. Possible correlation between miR-503 and fbillin1 (FBN1) was predicted according to data accessed on RNA22 website online, and was detected for confirmation by luciferase reporter assay. Results: Microarray analysis showed that miR- 503 was significantly decreased in the DFU tissues compared with normal tissues. While marked increase in the expression of miR-503 in tissues and serum of patients with DFU was confirmed by qRT-PCR technique. Then, CCK-8 assay indicated that transfection of miR- 503 mimic obviously accelerated the cell proliferation. However, TUNEL assays suggested that miR-503 mimic inhibited the apoptosis of cells to improve the survival of fibroblasts. Besides, miR-503 AMO played a role in fibroblasts of DFU tissues exactly countering to miR-503 mimic treatment. It was predicted that MiR-503 is a complementary to the FBN1 by RNA22. Besides, SiRNA-FBN1 promoted the proliferation, but brought down the apoptosis of fibroblasts. Conclusions: MiR-503 regulates the function of fibroblasts and wound healing of patients with DFU by targeting FBN1 directly which provids a novel and critical target for diagnosis and treatment of DFU.