ABSTRACT
The use of light emitting diodes (LED) as a therapeutic resource for wound healing has increased over the last years; however, little is still known about the molecular pathways associated to LED exposure. In the present study, we verified the effects of LED therapy on DNA methylation and expression of the DNA methyltransferase (Dnmt) genes, Dnmt1 and Dnmt3a, in an in vivo model of epithelial wound healing. Male Wistar rats were submitted to epithelial excision in the dorsal region and subsequently distributed within the experimental groups: group 1, animals that received irradiation of 0.8 J/cm(2) of LED (604 nm); group 2, animals that received 1.6 J/cm(2) of LED (604 nm); control (CTL), animals not submitted to therapeutic intervention. LED applications were performed during 7 days, and tissues from the periphery of the wound area were obtained for molecular analysis. The Image-J software was used for analysis of the wound area. DNA methylation was evaluated by ELISA-based method and gene expressions were quantified by real-time PCR. Decrease on global DNA methylation profile was observed in all experimental groups (CTL, 1, and 2) revealing the participation of DNA methylation in the healing process. Significant decrease in the wound area accompanied by increase in the Dnmt3a expression was associated to group 2. Based on our findings, we propose that DNA methylation is an important molecular mechanism associated to wound healing and that irradiation with 1.6 J/cm(2) of LED evokes an increase in the expression of the Dnmt3a that might associates to the efficiency of the epithelial wound healing.
Subject(s)
DNA (Cytosine-5-)-Methyltransferases/genetics , DNA (Cytosine-5-)-Methyltransferases/metabolism , DNA Methylation/radiation effects , Gene Expression Regulation, Enzymologic/radiation effects , Laser Therapy , Skin/pathology , Wound Healing/genetics , Wound Healing/radiation effects , Animals , DNA (Cytosine-5-)-Methyltransferase 1 , DNA Methyltransferase 3A , Disease Models, Animal , Male , Rats, Wistar , Real-Time Polymerase Chain Reaction , Skin/radiation effectsABSTRACT
O emprego de fontes de luz de baixa potência, como diodos emissores de luz-LEDs, pode propiciar um recurso terapêutico opcional aos convencionais ou ser utilizado em conjunto com estes, com a vantagem do baixo custo e comprovada eficiência no tratamento de úlceras e outras enfermidades. O estudo de caso foi realizado com um paciente do Ambulatório de Clinicas do HC/UEL que apresenta úlceras nos membros inferiores. A aplicação foi feita uma vez por semana, empregando LEDs com comprimento de onda de 628 nm na úlcera do membro inferior esquerdo e o direito foi utilizado como controle. A evolução foi medida por meio de registro fotográfico, medida da área e mensuração da dor. Foram realizadas 18 sessões. Os resultados apontaram mudanças nas características clínicas da lesão e a área cicatrizada foi 30% maior em relação à úlcera controle. Quanto à dor, a escala análoga visual variou de oito para zero no membro irradiado e de nove para dois no controle. Assim, pode-se concluir que a LED terapia é um recurso de eleição no tratamento da úlcera venosa, nos aspectos cicatriciais e redução da dor.
The use of low power light sources, such as diodes emitters of light LEDs, provides an alternative and complementary therapeutic resource to the conventional ones, with the advantage of being cost-effective and reliable in the treatment of ulcers and other infirmities. This study was carried out on a patient from the HC/UEL Outpatient Clinic with ulcers on both lower limbs. LEDs were applied once a week, using a wave length of 628 nm on the left lower limb ulcer ,using the right limb as control. Evolution was measured through photographic registers, area size and pain assessment. Eighteen sessions were performed. Results showed that changes were observed on the clinical characteristics of the injury and the healed area was 30% larger when compared to the control. As for the pain assessment, the visual analogue scale varied from eight to zero on the limb radiated and from nine to two on the control. Thus, it can be concluded that the LED therapy is a resource of choice for treating venous ulcer, in both healing and pain reduction aspects.
