miR-1246 regulates odontogenic differentiation of human dental pulp stem cells in an inflammatory microenvironment by targeting AXIN2: an in vitro study.
Abstract
Objective
This study aimed to investigate the modulatory function of microRNA-1246 (miR-1246) in the odontogenic differentiation of human dental pulp stem cells (hDPSCs) under inflammatory conditions in vitro and to elucidate its underlying molecular mechanism.
Methods
An inflammatory state was replicated in vitro by treating hDPSCs with lipopolysaccharide (LPS). miR-1246 expression was modulated via transfection with its mimics or inhibitors. Cell proliferation, movement, and apoptosis were assessed. Odontogenic differentiation capacity was assessed via alkaline phosphatase (ALP) activity, Alizarin Red S (ARS) staining, and transcript levels by quantitative real-time quantitative real-time polymerase chain reaction (qRT-PCR), along with Western blotting. To validate the direct interaction between miR-1246 and AXIN2, a dual-luciferase reporter assay was employed. All experiments were performed in three independent biological replicates.
Results
miR-1246 overexpression significantly reduced inflammatory cytokine levels (IL-1β, P < 0.05; IL-6, P < 0.05; TNF-α, P < 0.001) and partially restored hDPSC proliferation (P < 0.01), migration (P < 0.001), and survival (reduced apoptosis rate, P < 0.001). It also significantly increased ALP activity (P < 0.001), mineralized nodule formation (P < 0.001), and the expression of odontogenic markers (NRP1, DSPP, DMP1). Mechanistically, miR-1246 directly targeted AXIN2, preventing AXIN2-mediated β-catenin degradation and promoting the Wnt/β-catenin pathway, elevating downstream factors such as Cyclin D1 and c-Myc. AXIN2 knockdown reproduced the differentiation-promoting effects of miR-1246, whereas AXIN2 overexpression diminished them.
Conclusion
miR-1246 promotes the odontogenic differentiation of hDPSCs and partially counteracts the detrimental effects of inflammation in vitro by directly targeting and inhibiting AXIN2 expression, thereby stimulating the Wnt/β-catenin signaling cascade.