Open Access Research

Protective effects of aerobic exercise on acute lung injury induced by LPS in mice

Cintia Tokio Reis Gonçalves1, Carlos Gustavo Reis Gonçalves1, Francine Maria de Almeida2, Fernanda Degobi Tenório Quirino dos Santos Lopes2, Ana Carolina Cardoso dos Santos Durão4, Fabiana Almeida dos Santos4, Luiz Fernando Ferraz da Silva1, Tania Marcourakis4, Hugo C Castro-Faria-Neto3, Rodolfo de Paula Vieira15 and Marisa Dolhnikoff1*

Author Affiliations

1 Departamento de Patologia (LIM05) da Faculdade de Medicina da Universidade de São Paulo, Av. Dr. Arnaldo, 455 sala 1155, CEP 01246-903, São Paulo, Brazil

2 Departamento de Clínica Médica (LIM20) da Faculdade de Medicina da Universidade de São Paulo, Av. Dr. Arnaldo, 455 sala 1226, CEP 01246-903, São Paulo, Brazil

3 Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4365, CEP 21045-900, Rio de Janeiro, Brazil

4 Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Av. Prof. Lineu Prestes, 580 Bl 13B, CEP 05503-900, São Paulo, Brazil

5 Universidade Nove de Julho - UNINOVE, Rua Vergueiro 239/245, Vergueiro, CEP 01504-000, São Paulo - SP, Brazil

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Critical Care 2012, 16:R199  doi:10.1186/cc11807

Published: 18 October 2012

Abstract

Introduction

The regular practice of physical exercise has been associated with beneficial effects on various pulmonary conditions. We investigated the mechanisms involved in the protective effect of exercise in a model of lipopolysaccharide (LPS)-induced acute lung injury (ALI).

Methods

Mice were divided into four groups: Control (CTR), Exercise (Exe), LPS, and Exercise + LPS (Exe + LPS). Exercised mice were trained using low intensity daily exercise for five weeks. LPS and Exe + LPS mice received 200 µg of LPS intratracheally 48 hours after the last physical test. We measured exhaled nitric oxide (eNO); respiratory mechanics; neutrophil density in lung tissue; protein leakage; bronchoalveolar lavage fluid (BALF) cell counts; cytokine levels in BALF, plasma and lung tissue; antioxidant activity in lung tissue; and tissue expression of glucocorticoid receptors (Gre).

Results

LPS instillation resulted in increased eNO, neutrophils in BALF and tissue, pulmonary resistance and elastance, protein leakage, TNF-alpha in lung tissue, plasma levels of IL-6 and IL-10, and IL-1beta, IL-6 and KC levels in BALF compared to CTR (P ≤0.02). Aerobic exercise resulted in decreases in eNO levels, neutrophil density and TNF-alpha expression in lung tissue, pulmonary resistance and elastance, and increased the levels of IL-6, IL-10, superoxide dismutase (SOD-2) and Gre in lung tissue and IL-1beta in BALF compared to the LPS group (P ≤0.04).

Conclusions

Aerobic exercise plays important roles in protecting the lungs from the inflammatory effects of LPS-induced ALI. The effects of exercise are mainly mediated by the expression of anti-inflammatory cytokines and antioxidants, suggesting that exercise can modulate the inflammatory-anti-inflammatory and the oxidative-antioxidative balance in the early phase of ALI.