Angela Batista Gomes Santos

Toll-like receptors 2, 3 and 4 and thymic stromal lymphopoietin expression in fatal asthma

Airway inflammation in asthma involves innate immune responses. Toll‐like receptors (TLRs) and thymic stromal lymphopoietin (TSLP) are thought to be involved in airway inflammation, but their expression in asthmatics’ both large and small airways has not been investigated.

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-1β, keratinocyte chemoattractant (KC), and TNF-α in lung parenchyma was evaluated with immunohistochemistry. The levels of IL-1β, 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-1β, 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.

Effects of Chronic Exposure to Crack Cocaine on the Respiratory Tract of Mice

Smoked cocaine (crack cocaine) causes several forms of injury to the respiratory tract, including asthma exacerbations, lung edema and hemorrhage, and nasal mucosal alterations. Few studies, however, have assessed respiratory tract pathology in habitual users of crack cocaine. Here, we describe the histological alterations in the respiratory tract of mice caused by chronic inhalation of crack cocaine. Twenty 2-month-old BALB/c mice were exposed to the smoke of 5 g crack cocaine in an inhalation chamber once a day for two months and compared to controls (n = 10). We then morphometrically analyzed nose and bronchiolar epithelial alterations, bronchiolar and alveolar macrophage cell density, alveolar hemosiderin content, and in addition determined the vasoconstriction index and the wall thickness of pulmonary arteries. The serum cocaine level was 212.5 ng/mL after a single inhalation. The mucus content of the nasal epithelium increased in crack-exposed animals, and the nasal and bronchial epithelium thickness decreased significantly. The alveolar hemosiderin content and the alveolar and bronchiolar macrophage cell density increased in animals exposed to crack. The vasoconstriction index increased in the pulmonary arteries of the exposed group. Chronic crack cocaine inhalation causes extensive histological changes along the entire respiratory tract.

Bronchopulmonary lymph nodes and large airway cell trafficking in patients with fatal asthma

BACKGROUND Immune responses in asthmatic patients involve coordinated cellular responses in the airways and lymph nodes (LNs). However, no studies have described the composition of different cell populations in the bronchopulmonary LNs of asthmatic patients. OBJECTIVE We sought to investigate the expression of dendritic cells (DCs) and costimulatory molecules, B cells, T cells, TH2-related cytokines, eosinophils, and vascular cell adhesion molecule in the bronchopulmonary LNs and large airways of asthmatic patients. METHODS Using histochemistry, immunohistochemistry, and image analysis, we investigated the expression of Factor XIIIa(+), CD1a(+), CD83(+), and CD207(+) DCs; CD4(+) and CD8(+) T cells; CD20(+) B cells; CD23(+) (FcεRII) cells; IL-4; IL-5; eosinophils, and vascular cell adhesion molecule 1 in the large airways and bronchopulmonary LNs of 11 nonsmokers who died from an asthma exacerbation (fatal asthma [FA]) in comparison with 8 nonasthmatic control subjects. In selected cases of FA, we analyzed the coexpression of HLA-DR, CD40, and CD80 in lung and LN eosinophils. RESULTS The LNs of asthmatic patients exhibited increased density of eosinophils. No other cells were expressed differently in the LNs of patients with FA. The large airways of patients with FA had increased expression of eosinophils in all layers and increased expression of Factor XIIIa(+) cells, CD4(+) and CD8(+) T cells, CD20(+) B cells, and CD23(+) cells in the outer layer. There was colocalization of HLA-DR, CD40, and CD80 in the eosinophils at both sites. CONCLUSIONS FA is associated with the increased presence of eosinophils in the LNs and large airways, which express HLA-DR and costimulatory molecules. The expression of Factor XIIIa(+) monocyte-derived DCs, CD4(+) and CD8(+) T cells, CD20(+) B cells, and CD23(+) cells was increased in the large airways without a corresponding increase in the expression of these cells in the bronchopulmonary LNs. These findings support the concept that eosinophils might act as antigen-presenting cells in patients with FA.

Exercise Reduces Effects of Creatine on Lung

We recently demonstrated that creatine supplementation increased some features of lung allergic sensitization in mice. On the other hand, other studies have shown that aerobic exercise inhibited allergic airway inflammation and remodeling. We hypothesized that aerobic exercise may decrease the exacerbatory effects of the creatine supplementation in a murine model of asthma. Balb/c mice were divided into six groups: Control, Creatine (Cr), Low Intensity Exercise+Creatine (Low+Cr), Ovalbumin (OVA), Ovalbumin+Creatine (OVA+Cr) and Ovalbumin+Creatine+Low Intensity Exercise (OVA+Cr+Low). OVA-sensitized groups were sensitized with OVA intraperitoneal injections (days 0, 14, 28, and 42). Aerosol challenge (OVA 1%) and Cr treatment (0.5 g/kg/day) were initiated on Day 21 until Day 53. Low intensity exercise began on day 22 and was sustained until day 50. Low intensity exercise in the presence of creatine supplementation in sensitized mice resulted in a decreased number of eosinophils in BALF (p<0.001) and in the airways (p<0.001), and a decreased density of inflammatory cells positive to IL-4 (p<0.001) and IL-5 (p<0.001), airway collagen (p<0.001) and elastic fibers (p<0.001) content, airway smooth muscle thickness (p<0.001) and bronchoconstriction index (p<0.05) when compared with OVA+Cr group. These results suggest that aerobic exercise reduces the exacerbatory effects of creatine supplementation in chronically sensitized mice.

Aerobic Exercise Reduces Asthma Phenotype by Modulation of the Leukotriene Pathway

Introduction Leukotrienes (LTs) play a central role in asthma. Low- to moderate-intensity aerobic exercise (AE) reduces asthmatic inflammation in clinical studies and in experimental models. This study investigated whether AE attenuates LT pathway activation in an ovalbumin (OVA) model of asthma. Methods Sixty-four male, BALB/c mice were distributed into Control, Exercise (Exe), OVA, and OVA + Exe groups. Treadmill training was performed at moderate intensity, 5×/week, 1 h/session for 4 weeks. Quantification of bronchoalveolar lavage (BAL) cellularity, leukocytes, airway remodeling, interleukin (IL)-5, IL-13, cysteinyl leukotriene (CysLT), and leukotriene B4 (LTB4) in BAL was performed. In addition, quantitative analyses on peribronchial leukocytes and airway epithelium for LT pathway agents: 5-lypoxygenase (5-LO), LTA4 hydrolase (LTA4H), CysLT1 receptor, CysLT2 receptor, LTC4 synthase, and LTB4 receptor 2 (BLT2) were performed. Airway hyperresponsiveness (AHR) to methacholine (MCh) was assessed via whole body plethysmography. Results AE decreased eosinophils (p < 0.001), neutrophils (p > 0.001), lymphocytes (p < 0.001), and macrophages (p < 0.01) in BAL, as well as eosinophils (p < 0.01), lymphocytes (p < 0.001), and macrophages (p > 0.001) in airway walls. Collagen (p < 0.01), elastic fibers (p < 0.01), mucus production (p < 0.01), and smooth muscle thickness (p < 0.01), as well as IL-5 (p < 0.01), IL-13 (p < 0.01), CysLT (p < 0.01), and LTB4 (p < 0.01) in BAL were reduced. 5-LO (p < 0.05), LTA4H (p < 0.05), CysLT1 receptor (p < 0.001), CysLT2 receptor (p < 0.001), LTC4 synthase (p < 0.001), and BLT2 (p < 0.01) expression by peribronchial leukocytes and airway epithelium were reduced. Lastly, AHR to MCh 25 mg/mL (p < 0.05) and 50 mg/mL (p < 0.01) was reduced. Conclusion Moderate-intensity AE attenuated asthma phenotype and LT production in both pulmonary leukocytes and airway epithelium of OVA-treated mice.

Immune cell profile in infants' lung tissue.

Little is known about the normal immune cell profile in the lungs of infants without pulmonary disease. Normal lung samples obtained at autopsy of 10 infants that died either due to incidental or inflicted causes or non-pulmonary diseases were stained for antibodies against B and T lymphocytes, macrophages, NK cells, cytotoxic cells, dendritic cells and mast cells. Cells were quantified in the airway epithelial layer, inner layer (between the epithelium and the outer smooth muscle border), outer layer (between the outer smooth muscle border and the external limits of the airway) and alveolar septa. Basement membrane or alveolar septa lengths were assessed by image analysis. Results were expressed as cells/mm. The median age of patients was 6.8 months, ranging from 11 to 840 days. The inner layer of the airways was the region with the smallest density of cells. There was a predominance of cells related to the innate immunity such as CD56+, Granzyme B+ and CD68+ cells in the epithelial layer and alveolar parenchyma. The outer layer and the lung parenchyma presented the highest cellular density. There were very few CD4+ T cells or dendritic cells in most of the lung compartments. The numbers of CD3+ T and granzyme B+ cells correlated positively with age. There was a compartmentalization of immune cells along airways and parenchyma, which may be related to the development of innate and acquired lung defense mechanisms.

Repeated inhalation of crack-cocaine affects spermatogenesis in young and adult mice.

To investigate the effects of repeated crack-cocaine inhalation on spermatogenesis of pubertal and mature Balb/c mice, ten young (Yex) and ten adult (Aex) Balb/c mice were exposed to the smoke from 5 g of crack with 57.7% of pure cocaine in an inhalation chamber, 5 days/week for 2 months. The young (Yc) and adult (Ac) control animals (n = 10) were kept in a specially built and controlled animal house facility. The morphologic analysis of both testes of all animals included the analysis of quantitative and qualitative histologic parameters to assess the effect of crack-cocaine on spermatogenesis and Leydig cells. Apoptosis was determined by immunolabeling with caspase-3 antibodies. Compared to the Yc animals, Yex animals showed a significant reduction in the number of stage VII tubules per testis (p = 0.02), Sertoli cells (p < 0.001) and elongated spermatids (p = 0.001). Comparisons between the Yex and Aex groups identified a significant reduction in the number of Sertoli cells (p < 0.001) and round spermatids (p < 0.001) in the Yex group and a significant increase in apoptotic Leydig cells (p = 0.04) in the Aex group. The experimental results indicate that crack-cocaine smoke inhalation induced spermatogenesis disruption in chronically exposed mice, particularly in pubertal mice.

Creatine Activates Airway Epithelium in Asthma

Airway epithelium plays important roles in the pathophysiology of asthma. Creatine supplementation (Cr) was shown to increase asthma features in a murine model of allergic asthma; however, the role of the airway epithelium in this inflammatory response is not known. BALB/c mice were divided into control, creatine supplementation, ovalbumin-sensitized (OVA) and OVA plus creatine supplementation groups. OVA sensitization occurred on days 0, 14, 28 and 42, and ovalbumin challenge from days 21-53. Cr was also given on days 21-53. Total and differential cells counts in BALF were evaluated. Quantitative epithelial expression of interleukin (IL)-4, IL-5, IL-13, CCL11, CCL5, CCL2, iNOS, VCAM-1, ICAM-1, NF-κB, VEGF, TGF-β, IGF-1, EGFR, TIMP-1, TIMP-2, MMP-9, MMP-12 and arginase II were performed. Cr increased the number of total cells and eosinophils in BALF, the epithelial content of goblet cells and the epithelial expression of IL-5, CCL2, iNOS, ICAM-1, NF-κB, TGF-β, TIMP-1 and MMP-9 when compared to the control group (p<0.05). Creatine supplementation also exacerbated goblet cell proliferation, and IL-5 and iNOS expression by epithelial cells compared to the OVA group (p<0.01). Creatine up-regulates the pro-inflammatory cascade and remodelling process in this asthma model by modulating the expression of inflammatory mediators by epithelial cells.