Efficiency of peripheral nerve gaps restoration by different types of tissue engineering constructs according to electromyography: experimental study

Abstract

Objective. To investigate the effect of neural crest-derived multipotent stem cells (NC-MSCs) on the restoration of the peripheral nerve function according to the EMG.Materials and methods. Experimental animals: white outbreed male rats (5.5 months, 250±50 g, vivarium Romodanov Neurosurgery Institute n=52); groups: group 1 – nerve transection (with a 1 cm gap) and immediate autoplasty (n=14); group 2 – nerve transection and immediate plastic with collagen tube filled with fibrin gel (n=15); group 3 – nerve transection and immediate plastic with collagen tube filled with fibrin gel containing NC-MSCs (n=16); group 4 – sham operated animals (n=7). The key EMG parameters were determined using direct stimulation EMG at the 4th and 8th weeks of the experiment.Results. As at the end of the 4th week of observation in group 1, the amplitude of the M-response of the experimental limb was significantly (p=0.018) inferior to the value of the intact limb (3.3±0.5 mV versus 16.5±2.3 mV). In groups 2 and 3, statistically significant (p=0.018) values of the intact limb were observed for the amplitude of the M-response (group 2 – 16.5±2.3 mV versus 0.9±0.2 mV, group 3 – 14.7±2.2 mV versus 2.3±0.2 mV, p=0.018) and the conduction velocity (group 2 – 22.3±1.6 m/s versus 7.9±2.1 m/s (p=0.018; Mann – Whitney U test); group 3 – 19.3±2.5 m/s versus 12.7±0.4 m/s (p=0.049; Mann – Whitney U test). The value of the amplitude of the M-response in group 2 (0.9±0.2 mV) was significantly lower than that of group 1 (3.3±0.5 mV; p=0.006), group 3 (2.3±0, 2 mV; p=0.002) and group 4 (16.6±1.4 mV; p=0.006). As at the 8th week of observation, there was a significant advantage of the M-response amplitude of the experimental limb of animals in group 1 (4.1±0.7 mV) only above the value in group 2 (1.4±0.3 mV; p=0.007).Conclusions. NC-MSCs has a positive effect on the regeneration of PN due to stimulation of growth a greater number of nerve fibers than with implantation of a collagen matrix without NC-MSCs, which indirectly reflects key EMG indicators.