title: Low-level laser therapy in different stages of rheumatoid arthritis: a histological study.
abstract: Rheumatoid arthritis (RA) is an autoimmune inflammatory disease of unknown etiology. Treatment of RA is very complex, and in the past years, some studies have investigated the use of low-level laser therapy (LLLT) in treatment of RA. However, it remains unknown if LLLT can modulate early and late stages of RA. With this perspective in mind, we evaluated histological aspects of LLLT effects in different RA progression stages in the knee. It was performed a collagen-induced RA model, and 20 male Wistar rats were divided into 4 experimental groups: a non-injured and non-treated control group, a RA non-treated group, a group treated with LLLT (780 nm, 22 mW, 0.10 W/cm(2), spot area of 0.214 cm(2), 7.7 J/cm(2), 75 s, 1.65 J per point, continuous mode) from 12th hour after collagen-induced RA, and a group treated with LLLT from 7th day after RA induction with same LLLT parameters. LLLT treatments were performed once per day. All animals were sacrificed at the 14th day from RA induction and articular tissue was collected in order to perform histological analyses related to inflammatory process. We observed that LLLT both at early and late RA progression stages significantly improved mononuclear inflammatory cells, exudate protein, medullary hemorrhage, hyperemia, necrosis, distribution of fibrocartilage, and chondroblasts and osteoblasts compared to RA group (p < 0.05). We can conclude that LLLT is able to modulate inflammatory response both in early as well as in late progression stages of RA.
authors.affiliation: Post Graduate Program in Rehabilitation Sciences, Nove de Julho University (UNINOVE), Rua Vergueiro, 235, 01504-001, São Paulo, São Paulo, Brazil.
authors.forename: Ana Carolina Araruna
authors.initials: AC
authors.lastname: Alves
authors.forename: Paulo de Tarso Camillo
authors.initials: PT
authors.lastname: de Carvalho
authors.forename: Marcio
authors.initials: M
authors.lastname: Parente
authors.forename: Murilo
authors.initials: M
authors.lastname: Xavier
authors.forename: Lucio
authors.initials: L
authors.lastname: Frigo
authors.forename: Flávio
authors.initials: F
authors.lastname: Aimbire
authors.forename: Ernesto Cesar Pinto
authors.initials: EC
authors.lastname: Leal Junior
authors.forename: Regiane
authors.initials: R
authors.lastname: Albertini
mesh_terms: D000818:Animals; D001172:Arthritis, Rheumatoid / Q000139:chemically induced / Q000473:pathology* / Q000532:radiotherapy*; D019902:Chondrocytes / Q000473:pathology / Q000528:radiation effects; D003094:Collagen / Q000009:adverse effects; D004195:Disease Models, Animal; D005122:Exudates and Transudates / Q000528:radiation effects; D051445:Fibrocartilage / Q000473:pathology / Q000528:radiation effects; D028022:Low-Level Light Therapy; D008297:Male; D010006:Osteoblasts / Q000473:pathology / Q000528:radiation effects; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003094:Collagen