The Effect of Exanatide on Recovery of the Facial Nerve Crush Injury in the Rat.

BACKGROUND

Exenatide, a glucagon-like peptide-1 receptor agonist, has been shown to promote functional recovery and nerve regeneration after nerve crush injury. The aim of this study was to investigate the effect of exenatide on facial nerve regeneration in traumatic facial paralysis.

METHODS

This prospective, randomized animal study included 28 healthy female Sprague-Dawley rats divided into 4 groups of 7 rats each: control group, sham group, 2.5 μg/rat/day exenatide-treated group, and 10 μg/rat/day exenatide-treated group. Exenatide was injected subcutaneously for 14 days. Crush injury was applied to the left facial nerve in all groups except the sham group. Functional assessment, electrophysiological, histopathological, and immunohistochemical examinations were performed after crush injury.

RESULTS

The blink reflex score was higher in 10 μg exenatide-treated rats than in other rats at week 1. At weeks 3 and 4, the vibrissae movement score was higher in exenatide-treated rats than in untreated rats. Electromyographic assessments performed at weeks 2 and 4 showed higher amplitude values and shorter latency periods in the exenatide treatment groups. Exenatide was found to have a dose-dependent effect on reducing the severity of vasoconstriction, and this effect was statistically significant. When comparing the exenatide treatment groups with the control group, a significant reduction in the incidence of severe macrovacuolation and an increase in myelin thickness were observed (P < .05).

CONCLUSION

Functional, electrophysiological, and histopathological evaluations have shown that exenatide treatment has a positive and accelerating effect on facial nerve recovery in traumatic facial paralysis.