Transplantation of miRNA-34a overexpressing adipose-derived stem cell enhances rat nerve regeneration

Peripheral nerve injury is an ongoing challenge in reconstructive surgery. Adipose-derived stem cell (ADSC) application is reported to improve nerve regeneration. In the present study, we evaluated the potential benefit of 34a-ADSCs for never regeneration. Lentiviral vectors containing miRNA-34a were constructed and ADSCs were transduced. The obtained 34a-ADSCs were used to regenerate the sciatic nerve in surgically induced sciatic nerve injury rat model. Sprague-Dawley (SD) rats were randomly divided into two groups, a 34a-ADSC group and an Lv-ADSC group. Functional nerve recovery was assessed by walking track analysis at 12 weeks after surgery. In addition, histology, including light microscopy and transmission electron microscopy, and immunohistochemistry, was utilized to investigate the nerve repair effects of 34a-ADSC. Results showed that reconstruction of the injured sciatic nerve had been significantly enhanced by restoration of nerve continuity and functional recovery in the 34a-ADSC group compared with the Lv-ADSC group. Furthermore, sciatic nerve conduction velocity and compound nerve action potential in the 34a-ADSC group was much higher than that in the Lv-ADSC group (30.72 +/- 2.95 m/s vs. 22.73 +/- 1.91 m/s, p< 0.0001; 11.93 +/- 0.76 mV vs. 9.52 +/- 0.53 mV, p=0.0418). This study raises the possibility of using miRNA-34a overexpressed ADSCs as a promising alternative for nerve regeneration.