FTO-mediated m6A modification regulates the osteogenic differentiation of ADSCs by targeting FOXO1.

Using adipose-derived stem cells (ADSCs) has recently become a crucial approach for treating bone defects owing to their ease of accessibility and substantial differentiation potential. N6-methyladenosine (m6A) modification greatly influences biological processes and determines the differentiation fate of stem cells. However, the specific mechanisms by which m6A modification influences the osteogenic differentiation of ADSCs remain unclear. We identified FOXO1 as the key m6A-modified gene during the osteogenesis of ADSCs. Furthermore, demethylase FTO enhanced RUNX2 expression while inhibiting PPARG expression by modifying FOXO1, thereby facilitating ADSC osteogenesis. FTO knockdown inhibited ADSC migration and proliferation and impaired osteogenesis by suppressing FOXO1. At the mechanistic level, we first revealed that FTO was exported to the cytoplasm and then directly bound with FOXO1 mRNA at its 1760th bp site. Consistent use of non-steroidal anti-inflammatory drugs (NSAIDs) containing FTO inhibitors impeded ADSC-mediated bone formation both in vivo and in vitro. In summary, our study reveals the role of m6A modification based on the FTO-FOXO1-RUNX2/PPARG axis in regulating the osteogenic differentiation of ADSCs, thereby improving the clinical use of ADSCs and providing strategies for related drug applications in bone regeneration.