Change in inflammation in out-patient COPD patients from stable phase to a subsequent exacerbation

BACKGROUND: Inflammation increases during exacerbations of COPD, but only a few studies systematically assessed these changes. Better identification of these changes will increase our knowledge and potentially guide therapy, for instance by helping with quicker distinction of bacterially induced exacerbations from other causes. AIM: To identify which inflammatory parameters increase during COPD exacerbations compared to stable disease, and to compare bacterial and non-bacterial exacerbations. METHODS: In 45 COPD patients (37 male/8 female, 21 current smokers, mean age 65, FEV(1) 52% predicted, pack years 38) sputum was collected during a stable phase and subsequently during an exacerbation. RESULTS: Sputum total cell counts (9.0 versus 7.9 x 10(6)/mL), eosinophils (0.3 versus 0.2 x 10(6)/mL), neutrophils (6.1 versus 5.8 x 10(6)/mL), and lymphocytes (0.07 versus 0.02 x 10(6)/mL) increased significantly during an exacerbation compared to stable disease. A bacterial infection was demonstrated by culture in 8 sputum samples obtained during an exacerbation. These exacerbations had significantly increased sputum total cell and neutrophil counts, leukotriene-B4, myeloperoxidase, interleukin-8 and interleukin-6, and tumor necrosis factor-alpha (TNF-alpha) levels, and were also associated with more systemic inflammation compared to exacerbations without a bacterial infection. Sputum TNF-alpha level during an exacerbation had the best test characteristics to predict a bacterial infection. CONCLUSION: Sputum eosinophil, neutrophil, and lymphocyte counts increase during COPD exacerbations. The increase in systemic inflammation during exacerbations seems to be limited to exacerbations caused by bacterial infections of the lower airways. Sputum TNF-alpha is a candidate marker for predicting airway bacterial infection

Mouse Protocadherin-1 gene expression is regulated by cigarette smoke exposure in vivo

Protocadherin-1 (PCDH1) is a novel susceptibility gene for airway hyperresponsiveness, first identified in families exposed to cigarette smoke and is expressed in bronchial epithelial cells. Here, we asked how mouse Pcdh1 expression is regulated in lung structural cells in vivo under physiological conditions, and in both short-term cigarette smoke exposure models characterized by airway inflammation and hyperresponsiveness and chronic cigarette smoke exposure models. Pcdh1 gene-structure was investigated by Rapid Amplification of cDNA Ends. Pcdh1 mRNA and protein expression was investigated by qRT-PCR, western blotting using isoform-specific antibodies. We observed 87% conservation of the Pcdh1 nucleotide sequence, and 96% conservation of the Pcdh1 protein sequence between men and mice. We identified a novel Pcdh1 isoform encoding only the intracellular signalling motifs. Cigarette smoke exposure for 4 consecutive days markedly reduced Pcdh1 mRNA expression in lung tissue (3 to 4-fold), while neutrophilia and airway hyperresponsiveness was induced. Moreover, Pcdh1 mRNA expression in lung tissue was reduced already 6 hours after an acute cigarette-smoke exposure in mice. Chronic exposure to cigarette smoke induced loss of Pcdh1 protein in lung tissue after 2 months, while Pcdh1 protein levels were no longer reduced after 9 months of cigarette smoke exposure. We conclude that Pcdh1 is highly homologous to human PCDH1, encodes two transmembrane proteins and one intracellular protein, and is regulated by cigarette smoke exposure in vivo

Cigarette smoke-induced mitochondrial dysfunction and oxidative stress in

In this thesis we studied the effects of cigarette smoke (CS) on mitochondrial function and oxidative stress in epithelial cells and discussed the potential of these phenomena in the pathogenesis of chronic obstructive pulmonary diseases (COPD). In the first three chapters we demonstrated that CS disturbs mitochondrial function, increase reactive oxygen species (ROS) generation and alters the regulation of cell death. In chapter 4 and 5 we investigated the effects of gaseous-phase CS and H2O2 on the antioxidant glutathione and thiol proteins regulating redox state, morphology and cell death pathways in airway epithelial cells. In chapter 6 we studied the negative side effects of cyclosporine A (CsA), an immunosuppressive drug and potent inducer of mitochondrial permeability transition pore (MPTP) closure, on mitochondrial membrane potential, oxidative stress and calcium homeostasis in relation to chronic renal allograft dysfunction.

Design, Synthesis, and Inhibitory Activity of Potent, Photoswitchable Mast Cell Activation Inhibitors

<p>Allergic reactions affect millions of people worldwide. The need for new and effective antiallergic agents is evident, and insight into the underlying mechanisms that lead to allergic events is necessary. Herein, we report the design, synthesis, and activity of photoswitchable mast cell activation inhibitors. In mast cell degranulation assays, these inhibitors possess significantly greater potency than an original, chromone-based antiallergic agent. Furthermore, one of the photoswitchable inhibitors shows a significant difference in inhibitory activity between its two photoisomeric forms. Further optimization could ultimately lead to a photoswitchable compound suitable for studying mechanisms involved in allergic reactions in a novel manner, with activity addressable by light and with precise spatiotemporal control over events at the molecular level.</p>