Abstract
BACKGROUND: Exposure to Air pollution PM10 results in lung inflammation increased risk of lung cancer. Regular aerobic exercise improves the inflammatory status in different lung diseases. However, the effects of long-term aerobic exercise on the pulmonary response to PM10 have not been investigated. OBJECTIVES: The present study evaluated the effect of aerobic exercise on the lung inflammatory and risk of lung cancer of rat exposed to PM10 carbon black. MATERIALS AND METHODS: Twenty four adult male Wistar rats were divided into 4 groups: A: control (without exposure PM10 and aerobic exercise; n = 6), B: aerobic exercise (five times per week for 4 weeks; n = 6), C: exposure to PM10 carbon black (5 mg/m(3); per rat; n = 6), D: and aerobic exercise concomitantly with exposure to PM10 carbon black (n = 6). The gene expression of TLR4, NF-κB and TNF-α were analyzed in lung tissue by Real time-PCR. In order to determine the significant differences between groups, one way ANOVA and LSD post hoc and Kruskal-Vallis test were used. RESULTS: Aerobic exercise inhibited the PM10 -induced increase in the gene expression of TLR4, NF-κB and TNF-α. But there was significant different only between B and C groups for TNF-α and NF-κB (P = 0.047, 0.014, respectively). CONCLUSIONS: We conclude that four week aerobic exercise presents protective effects in a rat model of PM10 carbon black-induced lung inflammation and risk of lung cancer. Our results indicate a need for human studies that evaluate the lung Responses to aerobic exercise chronically performed in polluted areas.