Adam Antczak

A randomized, double-blind, placebo-controlled study of tumor necrosis factor-α blockade in severe persistent asthma

RATIONALE The treatment effect of golimumab, a human monoclonal antibody against tumor necrosis factor (TNF)-alpha, in severe persistent asthma is unknown. OBJECTIVES To assess the safety and efficacy of golimumab in a large population of patients with uncontrolled, severe persistent asthma. METHODS From 2004 to 2006, 309 patients with severe and uncontrolled asthma, despite high-dose inhaled corticosteroids and long-acting beta(2) agonists, were randomized 1:1:1:1 to monthly subcutaneous injections of placebo or golimumab (50, 100, or 200 mg) through Week 52. Coprimary endpoints were the change from baseline through Week 24 in prebronchodilator percent-predicted FEV(1) and the number of severe asthma exacerbations through Week 24. MEASUREMENTS AND MAIN RESULTS No significant differences were observed for the change in percent-predicted FEV1 (least squares mean: placebo, 2.44 [95% confidence interval (CI) -0.574 to 5.461]; combined 100-mg and 200-mg, 2.91 [0.696-5.116]) or severe exacerbations (mean +/- SD: placebo, 0.5 +/- 1.07 vs. combined 100-mg and 200-mg 0.5 +/- 0.97) through week 24. Through Week 24, 2.6% of patients treated with placebo vs. 19.5% of those treated with golimumab discontinued the study agent, and 1.3% and 7.8% discontinued study participation, respectively. An unfavorable risk-benefit profile led to early discontinuation of study-agent administration after the Week-24 database lock. Through Week 76, 20.5% of patients treated with placebo and 30.3% of patients treated with golimumab experienced serious adverse events, with serious infections occurring more frequently in golimumab-treated patients. One death and all eight malignancies occurred in the active groups. CONCLUSIONS Overall, treatment with golimumab did not demonstrate a favorable risk-benefit profile in this study population of patients with severe persistent asthma. Clinical trial registered with www.clinicaltrials.gov (NCT00207740).

Increased hydrogen peroxide and thiobarbituric acid-reactive products in expired breath condensate of asthmatic patients

Symptoms of bronchial asthma are a manifestation of airway inflammation. Circulatory leucocytes (predominantly eosinophils, mast cells and neutrophils), release inflammatory mediators, including reactive oxygen species, i.e. superoxide anion which is dismutated to hydrogen peroxide (H2O2). Neutrophils from asthmatics generate greater amounts of these species than those of healthy subjects. Some of the H2O2 and thiobarbituric acid-reactive products (TBARs) can evaporate from alveolar lining fluid, and could be expired from the airways of asthmatics. In this study, therefore, we determined whether asthmatic patients exhale more H2O2 and TBARs than healthy subjects. We examined 10 healthy subjects as a control group and 21 asthmatic subjects. In asthmatic subjects, forced expiratory volume in one second (FEV1), was 68+/-9% of predicted value, peak expiratory flow rate (PEFR) was 65+/-8% pred, and bronchial reversibility was 34+/-5% of prebronchodilated FEV1. The mean H2O2 level measured spectrofluorimetrically in the expired breath condensate of asthmatic subjects was 26 fold higher than that in healthy controls (0.26+/-0.29 vs 0.01+/-0.03 nM; p<0.05). The concentration of TBARs in breath condensate was also higher in asthmatic patients compared with nonasthmatics (0.073+/-0.071 vs 0.004+/-0.009 nM; p<0.05). There was a significant correlation between H2O2 level and concentration of TBARs in asthmatic patients (r=0.74; p<0.01). There was also a strong inverse correlation between H2O2 content of all asthmatics and FEV1% pred (r=-0.63; p<0.005) and PEFR% pred (r=-0.52; p<0.05). We conclude that there are elevated levels of hydrogen peroxide and thiobarbituric acid-reactive products in expired breath condensate of asthmatic patients, and that measurement of these substances in the expired breath condensate could be a simple, noninvasive method that could be used as a biochemical marker of airway inflammation.

Increased content of hydrogen peroxide in the expired breath of cigarette smokers

Cigarette smoking causes an influx of mononuclear phagocytes and polymorphonuclear leucocytes into the lower airways. These cells have altered oxygen metabolism and release more H2O2 than phagocytes from nonsmokers. In this study, we intended to determine whether asymptomatic cigarette smokers exhale more H2O2 than healthy nonsmokers. The content of H2O2 in the expired condensate of 27 nonsmokers and 33 cigarette smokers was measured spectrofluorimetrically (homovanillic acid method). The mean H2O2 level in the expired breath condensate of all cigarette smokers was about fivefold higher than that found in the whole nonsmoker group (0.24 +/- 0.32 versus 0.05 +/- 0.11 nM). However, only 16 smokers (49%) and 6 nonsmokers (22%) had detectable levels of H2O2 in expired breath that reached values 0.49 +/- 0.28 and 0.23 +/- 0.10 nM, respectively. Although the cigarette smoking status was similar for both male and female smokers, females expired 2.5 fold less H2O2 than males (0.15 +/- 0.24 (n = 21) versus 0.38 +/- 0.39 (n = 12) nM. No correlation was found between expired H2O2 levels and cigarette smoking status expressed as the daily cigarette consumption, cumulative cigarette consumption and urinary cotinine concentration. It is suggested that in some smokers, expressed H2O2 can be a noninvasive marker of oxidant overload in the lower airways related to cigarette smoking.

Antioxidant properties of ambroxol

We tested whether Ambroxol, a drug which stimulates the release of surfactant by pneumocytes type II, may also possess antioxidant properties. To assess the reactivity of Ambroxol with reactive oxygen species, we analysed its ability to decompose hydrogen peroxide (H2O2) and to inhibit the superoxide (O2.-)-dependent autooxidation of pyrogallol, hydroxyl radical (.OH)-mediated deoxyribose oxidation, and hypochlorous acid (HClO-induced chlorination of monochlorodimedon. Ambroxol was found to be a sufficient scavenger of HClO and .OH and also revealed the capacity to decompose H2O2. At concentrations of 25 and 70 microM, it inhibited HClO-induced chlorination of monochlorodimedon by 22 +/- 13 and 59 +/- 14%, respectively. Similarly, at concentrations of 1, 2, and 10 mM, Ambroxol decreased .OH-mediated deoxyribose oxidation by 47 +/- 11, 75 +/- 9, and 89 +/- 4%. In addition, at concentrations of 1 to 5 mM, it completely protected linoleic acid from .OH-induced peroxidative damage. Ambroxol had a weak effect on O2.(-)-dependent autooxidation of pyrogallol. Our results indicate that Ambroxol has antioxidant activity, which may have clinical significance in protecting lung tissue from oxidant-induced injury.

Protective effect of ambroxol against heat- and hydrogen peroxide-induced damage to lung lipids in mice

We wanted to determine whether ambroxol, a drug which stimulates the release of surfactant by type II pneumocytes, can protect lung lipids from peroxidative damage in mice. Animals were injected intraperitoneally with ambroxol, 0.169 mmol.kg-1, or 1 ml buffer once a day for three consecutive days. Lipid peroxidation was then induced in lung homogenates either by means of heat, 50 degrees C, or H2O2, 10 mmol.l-1. The lung homogenates from ambroxol-treated animals revealed decreased lipid peroxidation in response to both stimuli. The heat- and H2O2-induced generation of conjugated dienes (a first lipid peroxidation product) in ambroxol-treated lung homogenates was 3.7 and 3.1 fold lower than in the lungs from buffer-injected mice. Ambroxol, as an inhibitor of heat- and H2O2-induced lipid peroxidation, was equipotent to and stronger than the two antioxidants, N-acetylcysteine and methionine, respectively. Ambroxol was not able to protect heart and liver lipids. These results suggest that ambroxol can sufficiently enhance the antioxidant defence in lung tissue and can act as a lung lipid antioxidant.

Exhaled eicosanoids and biomarkers of oxidative stress in exacerbation of chronic obstructive pulmonary disease.

Introduction Eicosanoids and oxidants play an important role in inflammation, but their role in chronic obstructive pulmonary disease (COPD) is uncertain. In this study we hypothesized that levels of exhaled leukotrienes, prostaglandins and biomarkers of oxidative stress are increased in infectious exacerbations of COPD and that they decrease after antibiotic therapy. Material and methods Cysteinyl-leukotrienes (LTs), leukotriene B4 (LTB4), prostaglandin E4, hydrogen peroxide (H2O2) and 8-isoprostane were measured in exhaled breath condensate (EBC) in 16 COPD patients with infectious exacerbations (mean age 64 ±12 years, 13 male) on day 1, during antibiotic therapy (days 2-4), 2-4 days after therapy and at a follow-up visit when stable (21-28 days after therapy). Results There was a significant fall in concentration of cys-LTs, LTB4 and 8-isoprostane at visit 3 compared to day 1 (cys-LTs: 196.5 ±38.4 pg/ml vs. 50.1 ±8.2 pg/ml, p < 0.002; LTB4: 153.6 ±25.5 pg/ml vs. 71.9 ±11.3 pg/ml, p < 0.05; 8-isoprostane: 121.4 ±14.6 pg/ml vs. 56.1 ±5.2 pg/ml, p < 0.03, respectively). Exhaled H2O2 was higher on day 1 compared to that at visits 2 and 3 (0.74 ±0.046 µM vs. 0.52 ±0.028 µM and 0.35 ±0.029 µM, p < 0.01 and p < 0.01, respectively). Exhaled PGE2 levels did not change during exacerbations of COPD. Exhaled eicosanoids and H2O2 in EBC measured at the follow-up visit (stable COPD) were significantly higher compared to those from healthy subjects. Conclusions We conclude that eicosanoids and oxidants are increased in infectious exacerbations of COPD. They are also elevated in the airways of stable COPD patients compared to healthy subjects.

The significance of epigenetic alterations in lung carcinogenesis

Lung cancer is recognized as a leading cause of cancer-related death worldwide and its frequency is still increasing. The prognosis in lung cancer is poor and limited by the difficulties of diagnosis at early stage of disease, when it is amenable to surgery treatment. Therefore, the advance in identification of lung cancer genetic and epigenetic markers with diagnostic and/or prognostic values becomes an important tool for future molecular oncology and personalized therapy. As in case of other tumors, aberrant epigenetic landscape has been documented also in lung cancer, both at early and late stage of carcinogenesis. Hypermethylation of specific genes, mainly tumor suppressor genes, as well as hypomethylation of oncogenes and retrotransposons, associated with histopathological subtypes of lung cancer, has been found. Epigenetic aberrations of histone proteins and, especially, the lower global levels of histone modifications have been associated with poorer clinical outcome in lung cancer. The recently discovered role of epigenetic modifications of microRNA expression in tumors has been also proven in lung carcinogenesis. The identified epigenetic events in lung cancer contribute to its specific epigenotype and correlated phenotypic features. So far, some of them have been suggested to be cancer biomarkers for early detection, disease monitoring, prognosis, and risk assessment. As epigenetic aberrations are reversible, their correction has emerged as a promising therapeutic target.

Effect of bacterial lipopolysaccharide on the content of lipid peroxidation products in lungs and other organs of mice

The influence of lipopolysaccharide fromEscherichia coli (LPS, 17 mg/kg body weight) on the lipid peroxidation process in organs of mice was studied. The content of conjugated dienes (CD), lipid peroxides (LP), malondialdehyde (MDA) (all three lipid peroxidation by-products), peroxidase (PO) activity and wet-to-dry weight ratio in lungs, heart, spleen, kidneys and liver were determined 1.5 h after intravenous injection of LPS. Animals observed at this time-point had reduced activity and decreased body temperature by about 2°C, however, all analysed organs did not reveal any changes of wet-to-dry weight ratio comparing to organs from mice injected with sterile, pyrogen free 0,9% NaCl. Only extracts from heart and lungs showed significant increase in the tissue level of at least two lipid peroxidation products. The heart content of CD, MDA, and LP was about 1.5-, 1.3-, and 2.4-fold higher than in control group. In lungs CD and MDA increased 3.3- and 1.3-times but in spleen only content of LP was elevated. In these organs the suppression of PO activity was also observed. Liver and kidneys did not reveal any convincing enhancement of lipid peroxidation process and alterations of PO activity. Since free radical reactions are involved in lipid peroxidation process and inactivation of PO these results suggest that heart, lungs and spleen are the organs mostly exposed to oxidative stress during the first 1.5 h after single injection of LPS in mice.

Lipoxin A4 generation is decreased in aspirin‐sensitive patients in lysine‐aspirin nasal challenge in vivo model

Background:  Lipoxins represent a group of lipoxygenase derived eicosanoids which, in contrast to leukotrienes, are potent anti‐inflammatory mediators. The aim of our study was to determine lipoxin A4 (LXA4) and leukotriene C4 (LTC4) levels in nasal lavages after intranasal challenge with aspirin in aspirin intolerant (AIA) in comparison to aspirin tolerant (ATA) asthmatics and after allergen challenge in patients suffering from allergic rhinitis.

Correlation between eicosanoids in bronchoalveolar lavage fluid and in exhaled breath condensate

Exhaled breath condensate (EBC) has been increasingly used as a new and non-invasive method to study airway inflammation. In this study we have compared the concentrations of lipid mediators in EBCwith concentrations in bronchoalveolar lavage fluid (BALF). We included 37 patients undergoing bronchoscopy (12 sarcoidosis, 12 COPD, 6 lung cancer, 5 chronic cough, 1 Wegener’s granulomatosis, 1 sclerodermia). Patients were not allowed to have exacerbation or any change in concomitant medication for at least 4 weeks prior to the study. In all patients, EBC was collected immediately prior to the bronchoscopy. The levels of cys-LTs, LTB4, 8-isoprostane were significantly higher in BALF compared to EBC (p < 0.0001, p < 0.001, p < 0.0001 for cys-LTs, LTB4, 8-isoprostane respectively). Moreover, there was a strong positive correlation between both leukotriene B4 and 8-isoprostane in BALF and EBC (r = 0.53 and r = 0.79, p < 0.01, respectively) in patients with sarcoidosis and COPD but there was no correlation between eicosanoids BALF and EBC in patients with chronic cough and lung cancer. This is the first study to compare EBC and BALF in different lung diseases which demonstrated significant correlations between the levels of eicosanoids in BALF and EBCin patientswith COPD and sarcoidosis. EBC may be useful inmeasuring inflammation in several inflammatory lung diseases.