Exposure to Sodium Hypochlorite or Cigarette Smoke Induces Lung Injury and Mechanical Impairment in Wistar Rats.

Pulmonary irritants, such as cigarette smoke (CS) and sodium hypochlorite (NaClO), are associated to pulmonary diseases in cleaning workers. We examined whether their association affects lung mechanics and inflammation in Wistar rats. Exposure to these irritants alone induced alterations in the lung mechanics, inflammation, and remodeling. The CS increased airway cell infiltration, acid mucus production, MMP-12 expression, and alveolar enlargement. NaClO increased the number of eosinophils and macrophages in the bronchoalveolar lavage fluid, with cells expressing IL-13, MMP-12, MMP-9, TIMP-1, and iNOS in addition to increased IL-1ß and TNF-α levels. Co-exposure to both irritants increased epithelial and smooth muscle cell area, acid mucus production, and IL-13 expression in the airways, while it reduced the lung inflammation. In conclusion, the co-exposure of CS with NaClO reduced the pulmonary inflammation, but increased the acidity of mucus, which may protect lungs from more injury. A cross-resistance in people exposed to multiple lung irritants should also be considered.

Low-dose chlorine exposure impairs lung function, inflammation and oxidative stress in mice.

AIM: To explore the different consequences of acute and chronic exposure to chlorine gas (Cl2) on the functional and histological parameters of health mice. MAIN METHODS: Firstly, male BALB/c mice were acute exposed to 3.3 or 33.3 or 70.5 mg/m3 Cl2. We analyzed the lung function, the inflammatory cells in the bronchoalveolar lavage, cell influx in the peribrochoalveolar space and mucus production. In a second phase, mice were chronic exposed to 70.5 mg/m3 Cl2. Besides the first phase analyses, we also evaluated the epithelial cells thickness, collagen deposition in the airways, immunohistochemistry stain for IL-1ß, iNOS, IL-17 and ROCK-2 and the levels of IL-5, IL-13, IL-17, IL-1ß and TNF-α in lung homogenate. KEY FINDINGS: Acute exposure to chlorine impaired the lung function, increased the number of inflammatory cells in the BALF and in the airways, also increased the mucus production. Furthermore, when chlorine was exposed chronically, increased the airway remodeling with collagen deposition and epithelial cells thickness, positive cells for IL-1ß, iNOS, IL-17 in the airways and in the alveolar walls and ROCK-2 in the alveolar walls, lung inflammation with increased levels of IL-5, IL-13, IL-1ß and TNF-α in the lung homogenate, and also, induced the acid mucus production by the nasal epithelium. SIGNIFICANCE: Acute and chronic exposure to low dose of chlorine gas worsens lung function, induces oxidative stress activation and mucus production and contributes to augmenting inflammation in health mice.

Randomized trial of physiotherapy and hypertonic saline techniques for sputum induction in asthmatic children and adolescents.

OBJECTIVES: This study aimed to analyze the efficiency of physiotherapy techniques in sputum induction and in the evaluation of pulmonary inflammation in asthmatic children and adolescents. Although hypertonic saline (HS) is widely used for sputum induction (SI), specific techniques and maneuvers of physiotherapy (P) may facilitate the collection of mucus in some asthmatic children and adolescents. METHODS: A randomized crossover study was performed in patients with well-controlled asthma, and 90 sputum samples were collected. Children and adolescents were assessed using spirometry and randomized at entry into one of three sputum induction techniques: (i) 3% hypertonic saline - HS technique; (ii) physiotherapy (oscillatory positive expiratory pressure, forced expiration, and acceleration of expiratory flow) - P technique; and (iii) hypertonic saline + physiotherapy - HSP technique. ClinicalTrials.gov: NCT03136042. RESULTS: The total cells (mL) and the percentage (%) of differential inflammatory cells were similar in all techniques. The sputum weight (g) in the HSP technique was significantly higher than that in the HS technique. In all techniques, the percentage of viable cells was >50%, and there was no difference between the HS and P techniques. Moreover, sputum induction did not cause any alterations in the pulmonary function of patients. CONCLUSION: The physiotherapy sputum collection technique was effective in obtaining viable cells from mucus samples and yielded the same amount of sputum as the gold standard technique (hypertonic saline). In addition, the physiotherapy maneuvers were both safe and useful for sputum induction in asthmatic children and adolescents with well-controlled asthma.

Randomized trial of physiotherapy and hypertonic saline techniques for sputum induction in asthmatic children and adolescents

OBJECTIVES: This study aimed to analyze the efficiency of physiotherapy techniques in sputum induction and in the evaluation of pulmonary inflammation in asthmatic children and adolescents. Although hypertonic saline (HS) is widely used for sputum induction (SI), specific techniques and maneuvers of physiotherapy (P) may facilitate the collection of mucus in some asthmatic children and adolescents. METHODS: A randomized crossover study was performed in patients with well-controlled asthma, and 90 sputum samples were collected. Children and adolescents were assessed using spirometry and randomized at entry into one of three sputum induction techniques: (i) 3% hypertonic saline - HS technique; (ii) physiotherapy (oscillatory positive expiratory pressure, forced expiration, and acceleration of expiratory flow) - P technique; and (iii) hypertonic saline + physiotherapy - HSP technique. ClinicalTrials.gov: NCT03136042. RESULTS: The total cells (mL) and the percentage (%) of differential inflammatory cells were similar in all techniques. The sputum weight (g) in the HSP technique was significantly higher than that in the HS technique. In all techniques, the percentage of viable cells was >50%, and there was no difference between the HS and P techniques. Moreover, sputum induction did not cause any alterations in the pulmonary function of patients. CONCLUSION: The physiotherapy sputum collection technique was effective in obtaining viable cells from mucus samples and yielded the same amount of sputum as the gold standard technique (hypertonic saline). In addition, the physiotherapy maneuvers were both safe and useful for sputum induction in asthmatic children and adolescents with well-controlled asthma.

Author Correction: Low dose of chlorine exposure exacerbates nasal and pulmonary allergic inflammation in mice.

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Low dose of chlorine exposure exacerbates nasal and pulmonary allergic inflammation in mice.

Work-exacerbated asthma (WEA) is defined as preexisting asthma that worsens with exposure to irritants [e.g., chlorine (Cl2) derivatives] in the workplace. The maximum allowable concentration in the workplace of Cl2 exposure is 3 mg/ m3 (described in OSHA). We investigated in an experimental asthma model in mice the effects of a single exposure to a sodium hypochlorite dose with this allowed chlorine concentration and a tenfold higher dose. Acute chlorine exposure at 3.3 mg/m3 in the OVA-sensitized group increased eosinophils in the peribronquial infiltrate, cytokine production, nasal mucus production and the number of iNOS positive cells in the distal lung compared to only sensitized mice. The exposure to a higher dose of 33.3 mg/m3 in the OVA-sensitized group resulted in an increase in respiratory system elastance, in the total and differential numbers of inflammatory cells in bronchoalveolar lavage fluid, IL-4, IL-5, and IL-17 in the lungs, eosinophils in peribronquial infiltrate and mucus content in nasal compared to non-exposed and sensitized animals. In this asthma model, chorine exposures at an allowable dose, contributed to the potentiation of Th2 responses. The functional alterations were associated with increased iNOS and ROCK-2 activation in the distal lung.