title: Apoptosis induced by low-level laser in polymorphonuclear cells of acute joint inflammation: comparative analysis of two energy densities.
abstract: Anti-inflammatory property of low-level laser therapy (LLLT) has been widely described in literature, although action mechanisms are not always clarified. Thus, this study aimed to evaluate apoptosis mechanisms in the LLLT anti-inflammatory effects on the arthritis experimental model in vivo at two different energy densities (3 and 30 Jcm-2). Arthritis was induced in mice by zymosan solution, animals were distributed into five groups, and morphological analysis, immunocytochemistry and gene expressions for apoptotic proteins were performed. Data showed an anti-inflammatory effect, DNA fragmentation in polymorphonuclear (PMN) cells and alteration in gene expression of proteins related to apoptosis pathways after LLLT. p53 gene expression increased at both energy densities, Bcl2 gene expression increased at 3 Jcm-2, and Bcl2 tissue expression decreased at 30 Jcm-2. In addition, apoptosis was restricted to PMN cells. Results suggest that apoptosis in PMN cells comprise part of LLLT anti-inflammatory mechanisms by disbalance promotion between expression of pro-apoptotic (Bax and p53) and anti-apoptotic (Bcl-2) proteins, with pro-apoptotic gene expression selectively in PMN cells.
authors.affiliation: Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer, s/n-Campus Universitário, São Pedro, Juiz de Fora, Minas Gerais, 36036900, Brazil. luciamara.anjos@ufjf.edu.br.
authors.forename: Lúcia Mara Januário
authors.initials: LMJ
authors.lastname: Dos Anjos
authors.affiliation: Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier, 524, Maracanã, Rio de Janeiro, 20550900, Brazil.
authors.forename: Adenilson de Souza
authors.initials: AS
authors.lastname: da Fonseca
authors.affiliation: Departamento de Microbiologia, Parasitologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer, s/n-Campus Universitário, Juiz de Fora, Minas Gerais, 36036900, Brazil.
authors.forename: Jacy
authors.initials: J
authors.lastname: Gameiro
authors.affiliation: Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer, s/n-Campus Universitário, São Pedro, Juiz de Fora, Minas Gerais, 36036900, Brazil.
authors.forename: Flávia
authors.initials: F
authors.lastname: de Paoli
mesh_terms: D000208:Acute Disease; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects*; D001169:Arthritis, Experimental / Q000235:genetics / Q000473:pathology / Q000532:radiotherapy; D053938:DNA Fragmentation / Q000528:radiation effects; D005786:Gene Expression Regulation / Q000528:radiation effects; D007249:Inflammation / Q000235:genetics / Q000473:pathology*; D007596:Joints / Q000473:pathology*; D028022:Low-Level Light Therapy; D008297:Male; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000378:metabolism / Q000473:pathology* / Q000528:radiation effects*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015054:Zymosan
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D015054:Zymosan
keywords: Apoptosis; Bcl2; LLLT; Polymorphonuclear cells; p53