RESUMO
OBJECTIVE: This study aims to explore the mechanism of miR-211-5p in extracellular vesicles (EVs) derived from bone marrow mesenchymal stem cells (BMSCs) in improving frozen shoulder (FS) in rat models. METHODS: Rat BMSCs and EVs derived from rat BMSCs were isolated, identified, and then injected into rats to assess the expression of TGF-ß, MMP1, MMP3, MMP12, GAP43, and PGP9.5 in shoulder capsule tissues. The range of motion of bilateral glenohumeral joints was assessed and pathological changes of shoulder capsule tissues were observed after hematoxylin-eosin staining. The binding sites of miR-211-5p to KDM2B and LACC1 to H3K4me3 were measured. FS rat models with LACC1 highly expressed were established to assess the motion of bilateral glenohumeral joints and expression of arthritis related factors in rats. RESULTS: EVs were successfully extracted from BMSCs. Injection of BMSCs-EVs could improve the activity of bilateral glenohumeral joints and the pathological condition of joint capsule in rats. Elevated expression of miR-211-5p was found in rats injected with BMSCs-EVs. Dual luciferase assay showed that miR-211-5p had a binding site with KDM2B. ChIP, qRT-PCR, and western blot experiments showed BMSCs-EVs injection resulted in elevated enrichment of LACC1 promoter in shoulder capsule tissues of FS rats, and decreased mRNA and protein expression of KDM2B and increased H3K4me3 methylation. Overexpression of LACC1 could also improve the pathological condition of joint capsule tissue. CONCLUSION: miR-211-5p in EVs derived from BMSCs increased H3K4me3 methylation in shoulder capsule tissue of rats by binding KDM2B, resulting in up-regulated transcription level of LACC1 and improving FS. AVAILABILITY OF DATA AND MATERIALS: The datasets used or analyzed during the current study are available from the corresponding author on reasonable request.
