MicroRNA -130b downregulates PTEN and promotes osteogenesis in rat with tibial fracture through activation of Wnt/β-catenin signaling pathway.

Abstract

Fracture healing is a complex biological process involving multiple cellular and molecular mechanisms. Despite advances in understanding, the molecular regulation of bone regeneration remains incompletely understood. MicroRNAs (miRNAs) are emerging as critical post-transcriptional regulators of gene expression, with growing evidence suggesting their roles in osteogenesis and fracture repair. This study investigates the role of miRNA-130b in fracture healing and its molecular mechanisms, particularly focusing on its interaction with phosphatase and tensin homolog (PTEN) and the Wnt/β-catenin signaling pathway. Bone marrow mesenchymal stem cells (BMSCs) were isolated from rats and transfected with miRNA-130b mimic, inhibitor, or siPTEN. Osteogenic differentiation was assessed via alkaline phosphatase (ALP) activity, alizarin red S staining, and scratch wound healing assays. Pathway activation was evaluated using qRT-PCR and Western blotting. A rat tibial fracture model was established, and miRNA-130b mimic was administered intraperitoneally. Fracture healing was assessed via radiography, histology, and biomechanical testing at 2, 4, and 6 weeks post-surgery. MiRNA-130b overexpression enhanced BMSC proliferation, migration, and osteogenic differentiation by directly targeting PTEN and activating the Wnt/β-catenin signaling pathway. Conversely, miRNA-130b inhibition reduced osteogenic activity. MiRNA-130b mimic accelerated fracture healing, as evidenced by improved callus formation, enhanced bone mineralization, and superior biomechanical properties compared to control groups. miRNA-130b promotes osteogenesis and fracture healing by targeting PTEN and activating the Wnt/β-catenin signaling pathway. These findings highlight miRNA-130b as a promising therapeutic target for improving fracture repair outcomes.