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Introduction: Proteinase inhibitors have been associated with anti-inflammatory and antioxidant activities and may represent a potential therapeutic treatment for asthma., Purpose: The aim of the present study was to evaluate the effects of Enterolobium contortisiliquum trypsin inhibitor (EcTI) on pulmonary mechanical function, eosinophilic recruitment, inflammatory cytokines, remodeling and oxidative stress in an experimental model of chronic allergic pulmonary inflammation., Methods: BALB/c mice were divided into 4 groups: C (saline i.p and inhalations with saline), OVA (ovalbumin i.p and inhalations with ovalbumin); C+EC (saline i.p, inhalations with s aline and treatment with EcTI); OVA+EC (ovalbumin i.p, inhalations with ovalbumin and treatment with EcTI). On day 29, we performed the following tests: resistance (Rrs) and elastance (Ers) of the respiratory system; (b) quantify eosinophils, 8-ISO-PGF2α, collagen and elastic fiber volume fractions; (c) IFN-γ, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-β, iNOS and p65-NFκB-positive cells in the airway and alveolar walls., Results: In OVA+EC group, there was an attenuation of the Rrs and Ers, reduction of eosinophils, IL-4, IL-5, IL-13, IFN-γ, iNOS and p65-NFκB-positive cells compared to OVA group. The 8-ISO-PGF2α, elastic and collagen fibers volume fractions as well as the positive cells for MMP-9, TIMP-1 and TGF-β positive cells were decreased in OVA+EC compared to the OVA group., Conclusion: EcTI attenuates bronchial hyperresponsiveness, inflammation, remodeling and oxidative stress activation in this experimental mouse model of asthma.

Background . The epidemiologic association between pulmonary exposure to ambient particulate matter (PM) and acute lung damage is well known. However, the mechanism involved in the effects of repeated exposures of PM in the lung injury is poorly documented. This study tested the hypotheses that chronic nasal instillation of residual oil fly ash (ROFA) induced not only distal lung and airway inflammation but also remodeling. In addition, we evaluated the effects of inducible nitric oxide inhibition in these responses. For this purpose, airway and lung parenchyma were evaluated by quantitative analysis of collagen and elastic fibers, immunohistochemistry for macrophages, neutrophils, inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), and alveolar septa 8-iso prostaglandin F2 α (8-iso-PGF-2 α ) detection. Anesthetized i n vivo (airway resistance, elastance, H, G, and Raw) respiratory mechanics were also analyzed. C57BL6 mice received daily 60ul of ROFA (intranasal) for five (ROFA-5d) or fifteen days (ROFA-15d). Controls have received saline (SAL). Part of the animals has received 1400W (SAL+1400W and ROFA-15d+1400W), an iNOS inhibitor, for four days before the end of the protocol. A marked neutrophil and macrophage infiltration and an increase in the iNOS, nNOS, and 8-iso-PGF2 α expression was observed in peribronchiolar and alveolar wall both in ROFA-5d and in ROFA-15d groups. There was an increment of the collagen and elastic fibers in alveolar and airway walls in ROFA-15d group. The iNOS inhibition reduced all alterations induced by ROFA, except for the 8-iso-PGF2 α expression. In conclusion, repeated particulate matter exposures induce extracellular matrix remodeling of airway and alveolar walls, which could contribute to the pulmonary mechanical changes observed. The mechanism involved is, at least, dependent on the inducible nitric oxide activation.

We evaluated the effects of aerobic exercise (AE) on airway inflammation, exhaled nitric oxide levels (ENO), airway remodeling, and the expression of Th1, Th2 and regulatory cytokines in a guinea pig asthma model. Animals were divided into 4 groups: non-trained and non-sensitized (C), non-sensitized and AE (AE), ovalbumin-sensitized and non-trained (OVA), and OVA-sensitized and AE (OVA+AE). OVA inhalation was performed for 8 weeks, and AE was conducted for 6 weeks beginning in the 3rd week of OVA sensitization. Compared to the other groups, the OVA+AE group had a reduced density of eosinophils and lymphocytes, reduced expression of interleukin (IL)-4 and IL-13 and an increase in epithelium thickness (p<0.05). AE did not modify airway remodeling or ENO in the sensitized groups (p>0.05). Neither OVA nor AE resulted in differences in the expression of IL-2, IFN-γ, IL-10 or IL1-ra. Our results show that AE reduces the expression of Th2 cytokines and allergic airway inflammation and induces epithelium remodeling in sensitized guinea pigs., (Copyright © 2012 Elsevier B.V. All rights reserved.)

We evaluated the effects of cigarette smoke (CS) on lung inflammation and remodeling in a model of ovalbumin (OVA)-sensitized and OVA-challenged mice. Male BALB/c mice were divided into 4 groups: non-sensitized and air-exposed (control); non-sensitized and exposed to cigarette smoke (CS), sensitized and air-exposed (OVA) (50 μg+OVA 1% 3 times/week for 3 weeks) and sensitized and cigarette smoke exposed mice (OVA+CS). IgE levels were not affected by CS exposure. The increases in total bronchoalveolar fluid cells in the OVA group were attenuated by co-exposure to CS, as were the changes in IL-4, IL-5, and eotaxin levels as well as tissue elastance (p<0.05). In contrast, only the OVA+CS group showed a significant increase in the protein expression of IFN-γ, VEGF, GM-CSF and collagen fiber content (p<0.05). In our study, exposure to cigarette smoke in OVA-challenged mice resulted in an attenuation of pulmonary inflammation but led to an increase in pulmonary remodeling and resulted in the dissociation of airway inflammation from lung remodeling., (Copyright © 2012 Elsevier B.V. All rights reserved.)