Correlation between miR-1207-5p expression with steroid-induced necrosis of femoral head and VEGF expression

The aim of this study was to investigate the expression level of micro-ribonucleic acid-1207-5p (miR-1207-5p) in steroid-induced necrosis of femoral head (SNFH) and its correlation with SNFH. Meanwhile, we also aimed to analyze the relationship between miR-1207-5p expression and vascular endothelial growth factor (VEGF) in the femoral head.

From May 2016 to December 2017, 60 patients aged (55.4±8.7) were selected in our hospital. All patients were diagnosed and confirmed as SNFH. Total RNA was extracted from the necrotic femoral head tissues and peripheral blood. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was used to detect the expression level of miR-1207-5p in tissues. At the same time, immunohistochemistry and Western blotting were adopted to detect VEGF expression in the bone tissue of patients with high or low expression of miR-1207-5p. 7 patients with femoral neck fracture aged (45.6±4.51) were enrolled in the control group. In the animal experiment, the rat SNFH model was established by intraperitoneal injection of lipopolysaccharide and methylprednisolone. Subsequently, the expression levels of miR-1207-5p and VEGF in necrotic femoral tissues were detected. Meanwhile, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was applied to detect cell apoptosis in bone lacunae of miR-1207-5p high expression group and miR-1207-5p low expression group, respectively.

The expression level of miR-1207-5p in the necrotic bone tissue of the SNFH group was significantly higher than that of the control group. The expression level of miR-1207-5p was inversely proportional to Harris Hip score (p<0.05). A higher expression of miR-1207-5p indicated a lower expression level of VEGF (p<0.05). The animal experimental results revealed that miR-1207-5p expression in the necrotic femoral head tissue of SNFH group was significantly higher than that of the control group. Furthermore, the number of apoptotic cells in bone lacunae was remarkably higher in miR-1207-5p high expression group (p<0.05).

MiR-1207-5p is significantly up-regulated in necrotic femoral head tissue and serum of SNFH patients. Meanwhile, its expression level is inversely proportional to Harris Hip score of patients. The possible underlying mechanism may be related to the inhibitory effect of miR-1207-5p on VEGF.