No abstract

Peroxisome proliferator-activated receptor γ (PPARγ) plays a critical role in the control of airway inflammation. Recently, IL-17 has been found to be implicated in many immune and inflammatory responses, including airway inflammation. However, no data are available concerning the effect of PPARγ on IL-17 production in airway inflammatory diseases. In this study, we used a mouse model of asthma to evaluate the effect of two PPARγ agonists, rosiglitazone or pioglitazone, on IL-17 expression in allergic airway disease. After OVA inhalation, mice developed the typical pathophysiological features of asthma, and the expression of IL-17 protein and mRNA in the lungs was increased. Administration of rosiglitazone or pioglitazone reduced the pathophysiological features of asthma and decreased the increased IL-17 protein and mRNA expression after OVA inhalation. In addition, the attenuating effect of PPARγ agonist on allergic airway inflammation and bronchial hyperresponsiveness is abrogated by coadministration of rIL-17. This study also showed that the inhibition of IL-17 activity with anti-IL-17 Ab remarkably reduced the increased numbers of inflammatory cells of the airways, airway hyperresponsiveness, and the increased levels of IL-4, IL-5, and IL-13 in bronchoalveolar lavage fluid and OVA-specific IgE in serum. In addition, we found that administration of rosiglitazone or pioglitazone decreased the increased NF-κB activity and that a NF-κB inhibitor, BAY 11-7085, substantially reduced the increased IL-17 protein levels in the lung tissues after OVA inhalation. These findings suggest that the therapeutic effect of PPARγ in asthma is partly mediated by regulation of IL-17 expression via NF-κB pathway.

Vascular endothelial growth factor (VEGF) is a mediator of airway inflammation and remodelling in asthma. Transforming growth factor (TGF)-β1plays pivotal roles in diverse biological processes, including tissue remodelling and repair in a number of chronic lung diseases. However, there are few studies elucidating the interactions between VEGF and TGF-β1in allergic airway disease.A murine model of allergic airway disease was used to define the mechanism by which VEGF induces subepithelial fibrosis and to investigate a potential relationship between VEGF and TGF-β1and the mechanisms by which VEGF signalling regulates TGF-β1expression in allergic airway disease.The ovalbumin (OVA)-inhaled murine model revealed the following typical pathophysiological features of allergic airway disease in the lungs: increased numbers of inflammatory cells of the airways, airway hyperresponsiveness, increased peribronchial fibrosis, and increased levels of VEGF and TGF-β1. Administration of VEGF inhibitors reduced the pathophysiological signs of allergic airway disease and decreased the increased TGF-β1levels and peribronchial fibrosis, including phosphoinositide 3-kinase (PI3K) activity after OVA inhalation. In addition, the increased TGF-β1levels and collagen deposition after OVA inhalation were decreased by administration of PI3K inhibitors.These results suggest that inhibition of vascular endothelial growth factor attenuates peribronchial fibrosis, at least when mediated by regulation of transforming growth factor-β1expression through phosphoinositide 3-kinase/Akt pathway in a murine model of allergic airway disease.

These results suggest that mast cells modulate vascular permeability by the regulation of the PI3K-HIF-1alpha-VEGF axis.

Relatively little is known about the efficacy and safety of the programmatic use of bedaquiline and delamanid in multidrug-resistant tuberculosis (MDR-TB) treatment.This study evaluated 61 patients with MDR-TB treated with bedaquiline (n=39), delamanid (n=11) or both, either sequentially (n=10) or in coadministration (n=1), for >1 month, combined with a World Health Organization-recommended regimen.Of these, 49 (80.3%) were male and 12 (19.7%) were female. The median (interquartile range (IQR)) age was 53 (38.5-61.0) years. 42 (68.9%) patients had fluoroquinolone-resistant MDR-TB and 16 (26.2%) had extensively drug-resistant TB. The median (IQR) duration of treatment with bedaquiline and/or delamanid was 168 (166.5-196.5) days, with 33 (54.1%) receiving linezolid for a median (IQR) of 673 (171-736) days. Of the 55 patients with positive sputum cultures at the start of bedaquiline and/or delamanid treatment, 39 (70.9%) achieved sputum culture conversion within a median of 119 days. Treatment was halted in four patients (6.6%) because of prolonged Fridericia's corrected QT interval.Bedaquiline and delamanid were effective and safe for treating MDR-TB, with initial evidence of sequential administration of these two drugs as a viable treatment strategy for patients when an adequate treatment regimen cannot be constructed.