Avaliação do tratamento sistêmico com fotobiomodulação em modelo experimental de inflamação pulmonar aguda induzida por lipopolissacarídeo

Abstract

Acute Respiratory Distress Syndrome (ARDS) is a severe, multifactorial lung pa- thology characterized by diffuse alveolar injury, inflammatory cell infiltration, alveolar epithelial barrier rupture, alveolar edema and impaired pulmonary gas exchange, with a high rate of mortality; and sepsis is its most common cause. The mechanisms underlying acute lung inflammation due to systemic inflammation are investigated experimentally by systemic lipopolysaccharide (LPS) administration. Photobiomodulation has been showing good results for several inflammatory diseases, but there are not enough studies to support the real benefits of its use, especially systemically in the treatment of lung diseases. Considering that ARDS is a pathology with high morbidity and mortality, we studied the effect of systemic photobiomodulation with red LED in the management of inflammatory parameters of this disease. For this, male Wistar rats submitted to ARDS were injected by LPS (ip) and treated or not with LED systemically 2 and 6 h after ARDS induction. Our results point to the beneficial effects of systemic LED photobiomodulation on the LPS-induced ARDS model, as it reduced the number of neutrophils recruited into BAL, MPO activity and also reduced IL-1β, IL- 6 and IL-17 in the lung. Even considering the promising results, we highlight the importance of further studies to understand the mechanisms involved and especially the dosimetry, so that in the not so distant future we can apply this knowledge in clinical practice.