title: Increase in the nitric oxide release without changes in cell viability of macrophages after laser therapy with 660 and 808 nm lasers.
abstract: The aim of this study was to evaluate the influence of low-level laser therapy (LLLT) with different parameters and wavelengths on nitric oxide (NO) release and cell viability. Irradiation was performed with Ga-Al-As laser, continuous mode and wavelengths of 660 and 808 nm at different energy and power densities. For each wavelength, powers of 30, 50, and 100 mW and times of 10, 30, and 60 s were used. NO release was measured using Griess reaction, and cell viability was evaluated by mitochondrial reduction of bromide 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) to formazan. LLLT promoted statistically significant changes in NO release and MTT value only at the wavelength of 660 nm (p < 0.05). LLLT also promoted an increase in the NO release and cell viability when the energy densities 64 (p = 0.04) and 214 J/cm2(p = 0.012), respectively, were used. LLLT has a significant impact on NO release without affecting cell viability, but the significance of these findings in the inflammatory response needs to be further studied.
authors.affiliation: Department of Clinic and Preventive Dentistry, Pernambuco Federal University, Av. Prof. Moraes Rego, 1235, Recife, PE, Brazil, 50670-901. igorrecife@hotmail.com.
authors.forename: Igor Henrique Morais
authors.initials: IH
authors.lastname: Silva
authors.affiliation: Department of Clinic and Preventive Dentistry, Pernambuco Federal University, Av. Prof. Moraes Rego, 1235, Recife, PE, Brazil, 50670-901.
authors.forename: Samantha Cardoso
authors.initials: SC
authors.lastname: de Andrade
authors.affiliation: Department of Clinic and Preventive Dentistry, Pernambuco Federal University, Av. Prof. Moraes Rego, 1235, Recife, PE, Brazil, 50670-901.
authors.forename: Andreza Barkokebas Santos
authors.initials: AB
authors.lastname: de Faria
authors.affiliation: Department of Clinic and Preventive Dentistry, Pernambuco Federal University, Av. Prof. Moraes Rego, 1235, Recife, PE, Brazil, 50670-901.
authors.forename: Deborah Daniela Diniz
authors.initials: DD
authors.lastname: Fonsêca
authors.affiliation: Department of Clinic and Preventive Dentistry, Pernambuco Federal University, Av. Prof. Moraes Rego, 1235, Recife, PE, Brazil, 50670-901.
authors.forename: Luiz Alcino Monteiro
authors.initials: LA
authors.lastname: Gueiros
authors.affiliation: Department of Clinic and Preventive Dentistry, Pernambuco Federal University, Av. Prof. Moraes Rego, 1235, Recife, PE, Brazil, 50670-901.
authors.forename: Alessandra Albuquerque Tavares
authors.initials: AA
authors.lastname: Carvalho
authors.affiliation: Department of Nutrition, Pernambuco Federal University, Recife, PE, Brazil.
authors.forename: Wylla Tatiana Ferreira
authors.initials: WT
authors.lastname: da Silva
authors.affiliation: Department of Nutrition, Pernambuco Federal University, Recife, PE, Brazil.
authors.forename: Raul Manhães
authors.initials: RM
authors.lastname: de Castro
authors.affiliation: Department of Clinic and Preventive Dentistry, Pernambuco Federal University, Av. Prof. Moraes Rego, 1235, Recife, PE, Brazil, 50670-901.
authors.forename: Jair Carneiro
authors.initials: JC
authors.lastname: Leão
mesh_terms: D002470:Cell Survival / Q000528:radiation effects; D006801:Humans; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D028022:Low-Level Light Therapy / Q000379:methods*; D008264:Macrophages / Q000528:radiation effects*; D009569:Nitric Oxide / Q000378:metabolism*
chemical_list: D009569:Nitric Oxide
keywords: Inflammation; Laser therapy; MTT; Macrophages; NO; Nitric oxide