title: Low Level Laser Therapy Reduces the Development of Lung Inflammation Induced by Formaldehyde Exposure.
abstract: Lung diseases constitute an important public health problem and its growing level of concern has led to efforts for the development of new therapies, particularly for the control of lung inflammation. Low Level Laser Therapy (LLLT) has been highlighted as a non-invasive therapy with few side effects, but its mechanisms need to be better understood and explored. Considering that pollution causes several harmful effects on human health, including lung inflammation, in this study, we have used formaldehyde (FA), an environmental and occupational pollutant, for the induction of neutrophilic lung inflammation. Our objective was to investigate the local and systemic effects of LLLT after FA exposure. Male Wistar rats were exposed to FA (1%) or vehicle (distillated water) during 3 consecutive days and treated or not with LLLT (1 and 5 hours after each FA exposure). Non-manipulated rats were used as control. 24 h after the last FA exposure, we analyzed the local and systemic effects of LLLT. The treatment with LLLT reduced the development of neutrophilic lung inflammation induced by FA, as observed by the reduced number of leukocytes, mast cells degranulated, and a decreased myeloperoxidase activity in the lung. Moreover, LLLT also reduced the microvascular lung permeability in the parenchyma and the intrapulmonary bronchi. Alterations on the profile of inflammatory cytokines were evidenced by the reduced levels of IL-6 and TNF-α and the elevated levels of IL-10 in the lung. Together, our results showed that LLLT abolishes FA-induced neutrophilic lung inflammation by a reduction of the inflammatory cytokines and mast cell degranulation. This study may provide important information about the mechanisms of LLLT in lung inflammation induced by a pollutant.
authors.affiliation: Post Graduate Program in Biophotonics Applied to Health Sciences, University Nove de Julho (UNINOVE), São Paulo, Brazil.
authors.forename: Cristiane
authors.initials: C
authors.lastname: Miranda da Silva
authors.affiliation: Post Graduate Program in Biophotonics Applied to Health Sciences, University Nove de Julho (UNINOVE), São Paulo, Brazil.
authors.forename: Mayara
authors.initials: M
authors.lastname: Peres Leal
authors.affiliation: Post Graduate Program in Biophotonics Applied to Health Sciences, University Nove de Julho (UNINOVE), São Paulo, Brazil.
authors.forename: Robson Alexandre
authors.initials: RA
authors.lastname: Brochetti
authors.affiliation: Department of Immunology, University of São Paulo, São Paulo, Brazil.
authors.forename: Tárcio
authors.initials: T
authors.lastname: Braga
authors.affiliation: Post Graduate Program in Biophotonics Applied to Health Sciences, University Nove de Julho (UNINOVE), São Paulo, Brazil.
authors.forename: Luana Beatriz
authors.initials: LB
authors.lastname: Vitoretti
authors.affiliation: Department of Immunology, University of São Paulo, São Paulo, Brazil.
authors.forename: Niels Olsen
authors.initials: NO
authors.lastname: Saraiva Câmara
authors.affiliation: Department of Basic Science in Health, Faculty of Medical Sciences, Federal University of Cuiabá, Cuiabá, Brazil.
authors.forename: Amílcar Sabino
authors.initials: AS
authors.lastname: Damazo
authors.affiliation: Post Graduate Program in Biophotonics Applied to Health Sciences, University Nove de Julho (UNINOVE), São Paulo, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Ligeiro-de-Oliveira
authors.affiliation: Post Graduate Program in Medicine, University Nove de Julho (UNINOVE), São Paulo, Brazil.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Chavantes
authors.affiliation: Post Graduate Program in Biophotonics Applied to Health Sciences, University Nove de Julho (UNINOVE), São Paulo, Brazil.
authors.forename: Adriana
authors.initials: A
authors.lastname: Lino-Dos-Santos-Franco
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid; D015550:Cell Degranulation; D005557:Formaldehyde / Q000009:adverse effects*; D005786:Gene Expression Regulation; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D028022:Low-Level Light Therapy; D008168:Lung / Q000098:blood supply / Q000473:pathology; D008297:Male; D008407:Mast Cells / Q000378:metabolism; D055806:Microvessels / Q000473:pathology; D009504:Neutrophils / Q000378:metabolism; D010539:Permeability; D011014:Pneumonia / Q000209:etiology* / Q000235:genetics / Q000532:radiotherapy*; D017208:Rats, Wistar; D012130:Respiratory Hypersensitivity / Q000150:complications* / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D005557:Formaldehyde