title: Expression of DNA repair genes in burned skin exposed to low-level red laser.
abstract: Although red laser lights lie in the region of non-ionizing radiations in the electromagnetic spectrum, there are doubts whether absorption of these radiations causes lesions in the DNA molecule. Our aim was to investigate the expression of the genes involved with base excision and nucleotide excision repair pathways in skin tissue submitted to burn injury and exposed to low-level red laser. Wistar rats were divided as follows: control group-rats burned and not irradiated, laser group-rats burned and irradiated 1 day after injury for five consecutive days, and later laser group-rats injured and treated 4 days after injury for five consecutive days. Irradiation was performed according to a clinical protocol (20 J/cm(2), 100 mW, continuous wave emission mode). The animals were sacrificed on day 10, and scarred tissue samples were withdrawn for total RNA extraction, complementary DNA (cDNA) synthesis, and evaluation of gene expression by quantitative polymerase chain reaction. Low-level red laser exposure (1) reduces the expression of APE1 messenger (mRNA), (2) increases the expression of OGG1 mRNA, (3) reduces the expression of XPC mRNA, and (4) increases the expression of XPA mRNA both in laser and later laser groups. Red laser exposure at therapeutic fluences alters the expression of genes related to base excision and nucleotide excision pathways of DNA repair during wound healing of burned skin.
authors.affiliation: Laboratório de Reparo Tecidual Departamento de Histologia e Embriologia, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida Marechal Rondon 381-Pav. Jose Roberto Feresin Moraes, Rio de Janeiro, 20950-003, Brazil.
authors.forename: Eduardo Tavares Lima
authors.initials: ET
authors.lastname: Trajano
authors.forename: Andre Luiz
authors.initials: AL
authors.lastname: Mencalha
authors.forename: Andréa
authors.initials: A
authors.lastname: Monte-Alto-Costa
authors.forename: Luís Cristóvão
authors.initials: LC
authors.lastname: Pôrto
authors.forename: Adenilson
authors.initials: A
authors.lastname: de Souza da Fonseca
mesh_terms: D000818:Animals; D002056:Burns / Q000209:etiology*; D002352:Carrier Proteins / Q000378:metabolism; D045647:DNA Glycosylases / Q000378:metabolism; D004260:DNA Repair; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000378:metabolism; D020869:Gene Expression Profiling; D007834:Lasers; D028022:Low-Level Light Therapy / Q000009:adverse effects*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000378:metabolism / Q000528:radiation effects*; D014945:Wound Healing / Q000528:radiation effects*
chemical_list: D002352:Carrier Proteins; C534808:XPC protein, rat; D045647:DNA Glycosylases; C483741:OGG1 protein, rat; C470319:Apex1 protein, rat; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase