Efeitos da fotobiomodulação no processo apoptótico de células do ligamento periodontal de camundongos

Abstract

Photobiomodulation (PBM) by low-power infrared laser has been used to modulate the inflammatory and immune responses, pain relief and to promote wound healing. Therefore, PBM is widely used in dental practice and its cellular effects should be investigated. The aim of this work was to evaluate if PBM could alter caspase-6 and Bcl-2 mRNA relative levels in periodontal ligament cells. Eighteen mice were divided in three groups (n=6): (I) control, (II) 3 Jcm-2 and (III) 30 Jcm-2. Low-power infrared laser (830 nm) parameters were: power at 10 mW, energy densities at 3 and 30 Jcm-2 in continuous emission mode, exposure time of 15 and 150 s, respectively, for four days in a row. Twenty-four hours after last irradiation, the animals were euthanized, their jaws dissected, and Caspase-6 and Bcl-2 mRNA relative levels were analyzed by real time polymerase chain reaction. Statistical differences were not significant to Caspase-6 mRNA relative level in tissues from jaws at both energy densities (p>0.05), but a significant increase of Bcl-2 mRNA relative level was obtained at 30 Jcm-2 group (p<0.05). In conclusion, PBM can alter Bcl-2 mRNA relative level but cannot alter caspase-6 mRNA relative level, indicating anti-apoptotic effect in periodontal ligament cells.