Exosomes derived from miR-544-modified mesenchymal stem cells promote recovery after spinal cord injury

Recent evidence has demonstrated that exosomes derived from mesenchymal stem cells (MSCs) may serve as a reservoir of miRNAs conferring protection from certain diseases. Hence, the current study was performed with the aim of investigating whether MSCs-exosomal miR-544 could exert protection against spinal cord injury (SCI). In the present study, bone mesenchymal stem cells (BMSCs) isolated from rat bone marrows were transfected with miR-544 mimic. The miR-544-overexpressing BMSCs-derived exosomes (BMSC-Exo) were intravenously injected into SCI model rats. Neurological function, histopathological changes, and the release of inflammatory cytokines were further examined. Results showed that BMSCs-exosomal miR-544 mitigated neural functional recovery after SCI. Moreover, overexpression of miR-544 in BMSC-Exo abated histologic deficits and neuronal loss caused by SCI. Notably, this therapeutic intervention also reduced inflammation following SCI. In conclusion, exosomes derived from miR-544-overexpressing BMSCs improved functional recovery and promoted neuronal survival by attenuating inflammation after SCI.