Function of human insulin-like growth factor-1 (hIGF-1) transgene towards the regeneration of peripheral nerves in vivo

The aim of this study was to investigate the function of human insulin-like growth factor-1 (hIGF-1) transgene in vivo towards the regeneration of peripheral nerves. Thirty (30) male Wistar rats were randomly grouped after the sciatic nerve regeneration chamber model was set up. The hIGF-1 Treatment Group (TG) was injected the mixed solution of pcDNAhIGF-1 and LipfectAmine (hIGF-1 DNA was 4 ug) immediately at the spot of crush injury. The Treatment Model Group (MG) was injected 10 ul of the mixed solution of pcDNA3.1, LipfectAmine and physiological saline, while the control group (CG) was not injected any solution. The functional indexes of sciatic nerve were tested after 8 weeks of the injection. At the same time, electrophysiology of the regenerated nerve fibers, histology, morphology and ultrastructural organization observation were carried out. Compared with MG and CG, TG showed significant improvements in the fields of nerve conductive velocity of the regenerated nerve fibers, the greatest amplitude and electric potential of complex musculation electric potential (P<0.01). The axon diameter, medulla sheath thickness and medullated nerve fibers counts of the regenerated nerve fibers of TG were also higher than those of MG and CG (P<0.01). The degree of maturity of the regenerated nerve fibers of TG was better in the ultrastructural organization observation. Furthermore, other functional indexes were improved. hIGF-1 transgene in vivo could promote the regeneration of the injured peripheral nerves.