Creatine supplementation attenuates pulmonary and systemic effects of lung ischemia and reperfusion injury.

BACKGROUND: Creatine (Cr) is a dietary supplement that presents beneficial effects in experimental models of heart and brain ischemia and reperfusion (I/R) injury. It can improve adenosine 5'-triphosphate generation and reduce cell damage. This study evaluated the effects of Cr supplementation in a model of lung I/R. METHODS: Forty male Wistar rats were divided into 4 groups: sham operated, Cr+sham, I/R, and Cr+I/R. We investigated the effects of 5 days of Cr supplementation (0.5 g/kg/day by gavage) before left pulmonary artery ischemia (90 minutes) and reperfusion (120 minutes) on pulmonary and systemic response. RESULTS: Cr inhibited the I/R-induced increase in exhaled nitric oxide (p < 0.05), total cells (p < 0.01), and neutrophils (p < 0.001) in bronchoalveolar lavage fluid and in the systemic circulation (p < 0.001). The levels of interleukin-1ß (p < 0.05), tissue damping, and tissue elastance (p < 0.05) were also minimized. Cr also inhibited pulmonary edema formation (total proteins in bronchoalveolar lavage fluid, p < 0.001; histologic edema index, p < 0.001) and neutrophils accumulation in lung tissue (p < 0.001). As possible mechanisms underlying Cr effects, we observed a reduced expression of caspase 3 (p < 0.05), reduced expression of Toll-like receptor (TLR) 4, and increased expression of TLR7 in lung tissue (p < 0.001). CONCLUSIONS: Cr supplementation presents pulmonary and systemic protective effects in acute lung injury induced by I/R in rats. These beneficial effects seem to be related to the anti-inflammatory and anti-oxidant properties of Cr and modulation of TLRs.

Anacardic acids from cashew nuts ameliorate lung damage induced by exposure to diesel exhaust particles in mice.

Anacardic acids from cashew nut shell liquid, a Brazilian natural substance, have antimicrobial and antioxidant activities and modulate immune responses and angiogenesis. As inflammatory lung diseases have been correlated to environmental pollutants exposure and no reports addressing the effects of dietary supplementation with anacardic acids on lung inflammation in vivo have been evidenced, we investigated the effects of supplementation with anacardic acids in a model of diesel exhaust particle- (DEP-) induced lung inflammation. BALB/c mice received an intranasal instillation of 50 µ g of DEP for 20 days. Ten days prior to DEP instillation, animals were pretreated orally with 50, 150, or 250 mg/kg of anacardic acids or vehicle (100 µ L of cashew nut oil) for 30 days. The biomarkers of inflammatory and antioxidant responses in the alveolar parenchyma, bronchoalveolar lavage fluid (BALF), and pulmonary vessels were investigated. All doses of anacardic acids ameliorated antioxidant enzyme activities and decreased vascular adhesion molecule in vessels. Animals that received 50 mg/kg of anacardic acids showed decreased levels of neutrophils and tumor necrosis factor in the lungs and BALF, respectively. In summary, we demonstrated that AAs supplementation has a potential protective role on oxidative and inflammatory mechanisms in the lungs.

Anti-inflammatory effects of aerobic exercise in mice exposed to air pollution.

PURPOSE: Exposure to diesel exhaust particles (DEP) results in lung inflammation. Regular aerobic exercise improves the inflammatory status in different pulmonary diseases. However, the effects of long-term aerobic exercise on the pulmonary response to DEP have not been investigated. The present study evaluated the effect of aerobic conditioning on the pulmonary inflammatory and oxidative responses of mice exposed to DEP. METHODS: BALB/c mice were subjected to aerobic exercise five times per week for 5 wk, concomitantly with exposure to DEP (3 mg·mL(-1); 10 µL per mouse). The levels of exhaled nitric oxide, reactive oxygen species, cellularity, interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α) were analyzed in bronchoalveolar lavage fluid, and the density of neutrophils and the volume proportion of collagen fibers were measured in the lung parenchyma. The cellular density of leukocytes expressing IL-1ß, keratinocyte chemoattractant (KC), and TNF-α in lung parenchyma was evaluated with immunohistochemistry. The levels of IL-1ß, KC, and TNF-α were also evaluated in the serum. RESULTS: Aerobic exercise inhibited the DEP-induced increase in the levels of reactive oxygen species (P < 0.05); exhaled nitric oxide (P < 0.01); total (P < 0.01) and differential cells (P < 0.01); IL-6 and TNF-α levels in bronchoalveolar lavage fluid (P < 0.05); the level of neutrophils (P < 0.001); collagen density in the lung parenchyma (P < 0.05); the levels of IL-6, KC, and TNF-α in plasma (P < 0.05); and the expression of IL-1ß, KC, and TNF-α by leukocytes in the lung parenchyma (P < 0.01). CONCLUSIONS: We conclude that long-term aerobic exercise presents protective effects in a mouse model of DEP-induced lung inflammation. Our results indicate a need for human studies that evaluate the pulmonary responses to aerobic exercise chronically performed in polluted areas.