EPIGENETIC MODIFICATION IN ACETYL-HISTONE H3 IS ASSOCIATED WITH INCREASE OF ORAL WOUND HEALING AFTER PHOTOBIOMODULATION

Objective We aimed to evaluate the effect of photobiomodulation therapy (PBMT) on acetyl-histone H3 (acH3) expression during oral ulcer wound healing. Study Design Forty-eight male Wistar rats were divided into Control Group (CG) and PBMT Group. Traumatic ulcers were caused in the dorsum of the tongue with punch. Irradiation with InGaAlP laser, 660 nm, 40 mW, 0.04 cm2 spot size, 4 J/cm2, 4 seconds, and 0.16 J per point was performed once a day in close contact for 10 consecutive days. The CG received only daily handling. Rats were euthanized at days 3, 5, and 10 (n = 8) and were monitored daily to determine wound status. Immunohistochemical analysis for the detection of acH3 was performed. One thousand epithelial cells were counted and the mean of acH3 was calculated and compared between groups. Results PBMT accelerated the repair of oral ulcers. At day 3, PBMT showed a significantly higher mean of acH3 than GC (P = .04). On day 5, no difference was observed between the groups. On day 10, PBMT presented a lower mean of acH3 than the CG (P = .05). Conclusions PBMT stimulates the oral mucosa wound healing by activating epigenetic mechanisms such as histone acetylation in the early stages of the process. Fipe HCPA: 14-0572