Overexpression of miRNA-۲۱۶ in exosomes derived from umbilical cord mesenchymal stem cells promotes angiogenesis and improves functional recovery after spinal cord injury

Objective(s): This study aimed to engineer miR-۲۱۶-overexpressing umbilical cord mesenchymal stem cells (UCMSCs) to generate miR-۲۱۶-enriched UCMSC-derived exosomes (UCMSC-Exos) and evaluate their therapeutic potential in Spinal cord injury (SCI).Materials and Methods: miR-۲۱۶ overexpression was achieved in UCMSCs, and exosomes were subsequently isolated. The biological effects of miR-۲۱۶-overexpressing UCMSC-Exos (UCMSC-miR-۲۱۶OE-Exos) were assessed using in vitro migration, and tube formation assays with vascular endothelial cells. For in vivo evaluation, SCI mouse models were treated with either UCMSC-Exos or UCMSC-miR-۲۱۶OE-Exos. Functional recovery was measured using the BMS scores, while angiogenesis, neuronal apoptosis, and proinflammatory cytokine expression were analyzed through immunohistochemistry and molecular assays.Results: qPCR analysis confirmed successful miR-۲۱۶ overexpression in UCMSCs and their derived exosomes. In vitro, UCMSC-miR-۲۱۶OE-Exos significantly enhanced endothelial cell migration and tube formation compared to control UCMSC-Exos. In vivo, both UCMSC-Exos and UCMSC-miR-۲۱۶OE-Exos improved BMS scores, promoted angiogenesis, and reduced neuronal apoptosis and proinflammatory cytokine expression in SCI mice. Notably, UCMSC-miR-۲۱۶OE-Exos demonstrated superior therapeutic effects, including greater improvements in functional recovery, enhanced angiogenic responses, and more pronounced reductions in neuronal apoptosis and inflammation compared to control UCMSC-Exos. Additionally, in vitro experiments revealed that PTEN expression was down-regulated, and the AKT pathway was activated following treatment with UCMSC-miR-۲۱۶OE-Exos.Conclusion: These findings demonstrate that miR-۲۱۶-overexpressing UCMSC-Exos exhibits enhanced therapeutic efficacy in promoting angiogenesis, reducing inflammation and neuronal apoptosis, and improving functional recovery after SCI. This study demonstrates the promise of miR-۲۱۶-enriched exosomes as a novel cell-free therapeutic approach for SCI, paving the way for clinical translation through their biologically translatable mechanisms.

کلیدواژه ها:

Angiogenesis ، Exosomes ، miRNA-۲۱۶ ، Spinal cord injury ، Umbilical cord-mesenchymal stem cells