Effect of NGFβ/HIF-1α double transfected BMSCs on neuron axonal regeneration

Objective To observe the improvement of axonal regeneration microenvironment affected by NGFβ/HIF-1α double gene transfected bone marrow mesenchymal stem cells, and provide information about neuron axonal regeneration in microenvironment. Methods Lentiviral vector encoding NGFβ and HIF-1α were constructed and MOI were used to transfect BMSCs, then the expression of NGFβ and HIF-1α were detected by using western blot. Co-culture system with transwell double plates which include neurons and transfected BMSCs were constructed and then it was put in anaerobic tank for 48 hours, the expression of NGFβ, HIF-1α and VEGF in culture medium were detected by ELISA and the length of axons were measured by using Image pro-Plus software. There were five groups in this study, Group A: neuron without BMSCs; Group B: neuron with BMSCs; Group C: neuron with NGFβ transfected BMSCs; Group D: neuron with HIF-1α transfected BMSCs; Group E: neuron with NGFβ/HIF-1α double transfected BMSCs. Results The transfection efficiency of Le-RFP-NGF and Le-GFP-HIF-1α was 84.83% and 89.63%, respectively. Western blot analysis showed that transfected BMSCs could express the target protein NGFβ and HIF-1α. ELISA analysis of the co-culture system showed that the expression of NGFβ in Group C and Group E was significantly higher than in Group A and Group B (P＜ 0.05), the expression of HIF-1α in Group D and Group E was significantly higher than in Group A and Group B (P＜ 0.05). The expression of VEGF in Group D and Group E was significantly higher than in Group A and Group B. Image pro-Plus measurement showed that axon length of Group C, Group D and Group E was greater than that of Group A and Group B (P＜ 0.05), furthermore, axon length of Group E (neuron with NGFβ/HIF-1α double transfected BMSCs) was greater than that of Group C and Group D (P＜ 0.05). Conclusion The axons co-cultured with NGFβ/HIF-1α double transfected BMSC grow well and NGFβ, HIF-1α and VEGF, which play important roles in neuronal survival, are highly expressed in the coculture environment.