The effect of laser radiation on glial fibrillary acidic protein and allograft inflammatory factor-1 expression in severed and surgically repaired sciatic nerve.

objectiveDetermine the effect of different spectrum laser radiations on the expression of Glial Fibrillary Acidic Protein (GFAP) and allograft inflammatory factor-1 (Iba-1) in the sciatic nerve during regeneration.

methodsThe experiment was performed on 60 lab Wistar rats weighing 200-250 g. The left sciatic nerve was severed and subsequent end-to-end epineural suturing was performed 10, 20, 30, and 45 minutes after neurotomy. Western blot and immunohistochemistry analyses were performed by means of polyclonal anti-GFAP antibodies (Thermo Fisher Scientific, USA) and anti-Iba-1 antibodies (Invitrogen, USA) 90 days after nerve repair.

resultsThe use of green and blue spectrum laser radiation significantly increased GFAP protein expression regardless of the time when surgical nerve repair was performed after injury. The expression of Iba-1 and tubulin after blue spectrum laser radiation with a wavelength of 470 nm was significantly higher than the control values by 5.1-11.0 times. An increase in the expression of Iba-1 and tubulin was noted when a green spectrum laser with a wavelength of 560 nm was utilized and nerve suturing was performed 10 and 20 minutes after nerve injury. The green spectrum laser with a wavelength of 520 nm had no significant effect on the expression of Iba-1 and tubulin. Morphologically, the highest proliferative reaction of glia was recorded when using a blue spectrum laser.

conclusionsLaser radiation with blue (470 nm) and green (560 nm) spectra, promoted the activation of GFAP-positive Schwann cells and nerve regeneration. Activation of microglia is a necessary component of nerve regeneration and the content of Iba-1 represented the efficiency of regeneration.