Mice exposed to HQ showed augmented levels of MDA and enhanced ROS generation by neutrophils in comparison to samples obtained from vehicle-exposed animals (Fig. 1A and B, respectively). On the contrary, no differences were detected in the two animal groups with regard to global DNA fragmentation (Fig. 1C). In vivo exposure to HQ at 12.5, 25 or 50 ppm did not modify the number of circulating Selleckchem EPZ015666 leukocytes after LPS challenge. The number of neutrophils and mononuclear cells (MN) was not statistically different in vehicle- and HQ-exposed

animals ( Table 1). Normal values of polymorphonuclear leukocytes (PMN) in mouse blood are around 15–20%, and they are highly elevated after acute inflammation. This pattern of response was detected in both groups of animals, indicating that neutrophil mobilization from storage compartments was not affected by HQ exposure. It is noteworthy that the levels of PMN and MN in vehicle- and HQ-exposed animals ( Table 1) must be compared in groups of animals submitted

to the same concentration exposure, since assays were performed on different days and total leukocyte numbers for the mice ranges about 3500–6000/mm3. Corroborating that HQ exposure does not affect neutrophil delivery from bone marrow or cell maturation steps, cell cycle was equivalent in circulating cells obtained Crizotinib molecular weight from vehicle- or HQ-exposed animals ( Fig. 2). On the other hand, exposure to 12.5, 25 or 50 ppm of HQ reduced the neutrophil numbers recovered in BALF (Fig. 3A), and these cells seemed to persist inside the lung tissue, since MPO levels of lung were higher than those obtained for vehicle-exposed animals (Fig. 3B). Numbers of neutrophils in BALF, obtained in vehicle-exposed and non-inflamed animals, was almost 50% less in comparison to the LPS-stimulated control group (Fig. 3A, dotted line), indicating the efficiency of LPS in inducing lung inflammation and that circulating neutrophils from

vehicle-exposed animals were able to migrate to the alveolar compartment. As the three concentrations of HQ similarly reduced the number of PMN in the BALF, and 25 ppm exposure next promoted more homogenous responses, the following study was conducted with animals exposed to 25 ppm of HQ. As IL-1β, TNF-α and IL-6 are involved in leukocyte migration by inducing the expression of adhesion molecules and secretion of chemoattractant factors (Barreiro et al., 2010), the effects of HQ exposure on these cytokines in BALF were investigated using ELISA. The data obtained demonstrated that HQ did not modify the baseline or LPS-induced secretion of these cytokines (Fig. 4). In vivo exposure to HQ did not modify the LPS-induced expression of endothelial E- and P-selectins ( Fig. 5A) and ICAM-1, VCAM-1 and PECAM-1 ( Fig. 5B). Baseline expression of these molecules was very low in lung tissue and did not differ between the two animal groups studied (data not shown).