Cationic Liposome-Mediated Bcl-2 Gene Transfection in Bone Marrow Mesenchymal Stem Cells: A Novel Regenerative Approach for Spinal Cord Injury.

OBJECTIVE: This study explored a novel therapy for spinal cord injury (SCI) using cationic liposomes to deliver the anti-apoptotic Bcl-2 gene into rat bone marrow mesenchymal stem cells (BMSCs), followed by transplantation into a rat SCI model to evaluate its potential in promoting neural regeneration and enhancing SCI therapy. METHODS: BMSCs were isolated and characterized for surface markers and differentiation potential, and transfected with Bcl-2 via cationic liposomes. A rat SCI model was established to assess the therapeutic effects of BMSCs and Bcl-2-BMSCs. Functional recovery was evaluated using the Basso, Beattie, and Bresnahan (BBB) scale and inclined plate test, while histopathology, Western blot, and real-time polymerase chain reaction (RT-PCR) analyses were performed to assess neural recovery. Nissl and myelin staining were used to evaluate neuronal and myelin recovery. RESULTS: Following successful characterization of BMSCs and the spherical cationic liposomes (105 ± 1.3 nm, 18.65 ± 1.37 mV zeta potential), optimal transfection conditions were identified. Bcl-2-transfected BMSCs expressed high levels of Bcl-2 with low toxicity. In addition, the SCI results showed significant improvements in the BBB and inclined plate scores of rats in the BMSCs and Bcl-2-BMSCs groups compared to the model group (p< 0.01). HE-stained samples demonstrated that the secretion of Bcl-2 and BMSCs plays a crucial role in SC repair. Western blot results revealed an upregulation of proteins associated with neural recovery (Bcl-2, β-tubulin3, MAP2, NF-200, MBP) and a downregulation of the glial scar-associated protein GFAP in both the BMSCs and Bcl-2-BMSCs groups. Furthermore, Nissl staining and myelin staining showed that both the BMSCs and Bcl-2-BMSCs groups exhibited enhanced neuronal survival, inhibition of demyelination, and significant myelin regeneration. CONCLUSION: Transplantation of Bcl-2-transfected BMSCs represents a highly promising strategy that effectively promotes neural regeneration, inhibits scar formation, reduces demyelination, and enhances functional recovery, highlighting its potential for clinical translation.