Katarzyna Grzela

Airway Remodeling in Chronic Obstructive Pulmonary Disease and Asthma: the Role of Matrix Metalloproteinase-9

Chronic obstructive pulmonary disease (COPD) and asthma are both associated with airflow restriction and progressive remodeling, which affect the respiratory tract. Among various biological factors involved in the pathomechanisms of both diseases, proteolytic enzymes—matrix metalloproteinases (MMPs)—play an important role, especially MMP-9. In this review, the authors discuss the current topics of research concerning the possible role of MMP-9 in both mentioned diseases. They include the analysis of protein levels, nucleotide polymorphisms of MMP-9 gene and their possible correlation with asthma and COPD. Finally, the authors refer to the studies on MMP-9 inhibition as a new perspective for increasing the effectiveness of treatment in asthma and COPD.

Prolonged Treatment with Inhaled Corticosteroids does not Normalize High Activity of Matrix Metalloproteinase-9 in Exhaled Breath Condensates of Children with Asthma.

The airway remodeling in asthma is associated with increased amount of matrix metalloproteinase (MMP)-9. High levels of MMP-9 were found in mucosal biopsies, sputum and in exhaled breath condensates (EBC) of asthma patients. However, there are no data concerning real in vivo activity. Inhaled corticosteroids are effective in asthma control, but it is unclear, whether they only attenuate inflammation, or also protect against progressive remodeling of respiratory tract. Therefore, the aim of the study was to assess the amount and activity of MMP-9 in context of pro-inflammatory cytokines (IL-6, IL-8 and tumor necrosis factor, TNF), measured in EBC of asthma-suffering children, treated with inhaled steroids. The study involved 27 children with asthma, continuously treated with inhaled fluticasone propionate, and 22 healthy controls. In addition to routine clinical screening, the selected cytokines in EBC were analyzed using Ultrasensitive ELISA, whereas activity of MMP-9 was assessed using a novel immunozymography method. Despite chronic treatment with inhaled steroids mean MMP-9/EBC activity in asthma group was significantly higher than in healthy controls. Moreover, high MMP-9/EBC in asthma-suffering children significantly correlated with IgE serum levels. The IL-6 and IL-8 concentration was below the detection limit in all EBC samples. TNF/EBC levels were similar in both, asthma and healthy children. We hypothesize that MMP-9 hyperactivity in asthma may be closely related to high IgE serum levels. Our results suggest that inhaled steroids may be ineffective to prevent asthma-associated airway remodeling. Finally, we emphasize the necessity of further research focused on MMP-9 inhibition in asthma treatment.

Immunostimulatory oligonucleotides in therapy of allergic diseases

At present, the improvement of hygienic life standards is considered as an environmental condition, increasing the prevalence of allergic diseases, as early contact with some pathogens is, according to the hygiene hypothesis, required for maturation of the immune system. The recognition of microbial components involves acquired and innate immunity mechanisms. Recently, the link between innate and acquired immunity has been discovered. It involves the evolutionarily old Toll-like receptor (TLR) system. Ligands recognised by TLRs include unmethylated deoxycytidil-deoxyguanosine (CpG) motif-containing microbial DNA. TLR-mediated signalling induces expression of cytokines preferentially promoting a Th1-directed response. Therefore, synthetic CpG motif-containing immunostimulatory oligonucleotides could be employed in causal allergy treatment. This review discusses some molecular aspects of the TLR system, as well as results of animal studies and early experiences, including treatment safety, from human clinical trials with immunostimulatory CpG motif-containing oligonucleotides.

Nitric oxide, IL-6 and IL-13 are increased in the exhaled breath condensates of children with allergic rhinitis.

To evaluate nitric oxide and interleukin (IL)‐6, IL‐8 and IL‐13 in the exhaled breath of children with allergic rhinitis (AR), before and after intranasal allergen exposure.

Inhaled corticosteroids do not reduce initial high activity of matrix metalloproteinase (MMP)-9 in exhaled breath condensates of children with asthma exacerbation: a proof of concept study

Inhaled corticosteroids (ICS) are the key component of asthma treatment. However, it is unclear whether they could control the activity and level of matrix metalloproteinase (MMP)-9, which is an important factor in asthma-associated inflammation and airway remodeling. Therefore, the aim of this proof of concept study was to analyze the influence of increased doses of ICS on MMP-9 in exhaled breath condensates (EBC) of patients with allergic asthma exacerbation. Apart from MMP-9, the assessment concerned selected inflammation markers – exhaled nitric oxide (eNO) and cytokines (IL-8 and TNF). The study involved a small group (n = 4) of individuals with asthma exacerbation. The intervention concerned increased doses of ICS with β-mimetics for 4 weeks. In addition to clinical evaluation, eNO measurements and EBC collections were done before and after 4 weeks of intense ICS treatment. The biochemical assessment of EBC concerned MMP-9, IL-8 and TNF. The data were compared to results of healthy controls (n = 6). The initial levels of eNO, MMP-9 and TNF in EBC were higher in the asthma group than in controls. In all subjects IL-8 levels were below the detection limit. After 4 weeks of ICS treatment in all patients we observed improvement of clinical and laboratory parameters. Interestingly, despite reduction of eNO and TNF, the activity of MMP-9/EBC remained on the initial level. Practical relevance of our results is limited by a small group. Nevertheless, our data suggest that ICS, although sufficient to control symptoms and inflammatory markers, may be ineffective to reduce MMP-9/EBC activity in asthma exacerbation and, possibly, airway remodeling.

Inflammatory Cytokines in Exhaled Breath Condensate in Children With Inflammatory Bowel Diseases

Although inflammatory bowel diseases (IBD) affect mainly the gastrointestinal tract, the extra‐intestinal manifestations are not uncommon. Different diagnostic methods have been applied to assess pulmonary involvement in patients with IBD, but majority of these methods show significant limitations in children. The aim of our study was to evaluate the usefulness of exhaled breath condensate (EBC) measurements of pro‐inflammatory cytokines in children with IBD.

Pulmonary arteriovenous malformations: clinical and radiological presentation.

History Exertional dyspnea for 4 years, medical and family history unremarkable Exertional dyspnea for 2 years, migraine headaches, medical and family history unremarkable Symptoms Central cyanosis, finger clubbing, no abnormalities on heart and lung examination Central cyanosis, finger clubbing, growth retardation (body weight <3rd percentile) no abnormalities on heart and lung examination Laboratory tests RBC, 6.26 T/L; Hct, 54.2%, Hb, 18.8 g/dL, PaO2, 55 mm Hg RBC, 6.02 T/L, Hct, 52.8%, Hb, 18.4 g/dL PaO2, 52 mm Hg Chest radiograph Well-defined round opacity in the midLarge, well-defined oval opacity in the midT were treated in our institution; in both cases, the initial symptoms included exertional dyspnea and cyanosis. The signs and symptoms as well as results of laboratory tests and chest radiographs on admission are presented in the Table. The masses found on chest radiographs were further assessed by contrast-enhanced spiral computed tomography. Computed tomography identified both lesions as large pulmonary arteriovenous fistulas (PAVFs) (Figures 1 and 2). A small PAVF in the right upper lobe was also demonstrated in case 1 (Figure 3; available at www.jpeds.com). In both cases, underlying diseases such as hereditary hemorrhagic telangiectasia were excluded. The patients were treated with percutaneous coil embolization. This resulted innormalization of PaO2, RBC, and Hb values and subsequent resolution of clinical symptoms. Pulmonary arteriovenous fistulas are a rare clinical entity. The most common clinical presentation of large PAVFs in

Polymorphic Variants 279R and 668Q Augment Activity of Matrix Metalloproteinase-9 in Breath Condensates of Children with Asthma

Matrix metalloproteinase (MMP)-9 is involved in pathophysiology of asthma, mainly asthma-associated airway remodeling. Exhaled breath condensates (EBC) of asthmatics contain increased amounts of MMP-9 with activity higher, than in healthy controls. The increased activity of MMP-9 may originate from its excessive production and activation, but may also result from variations in MMP-9 structure, which are determined by single nucleotide polymorphisms (SNPs). In this pilot study we aimed to assess the possible influence of two functional MMP-9 polymorphisms, Q279R and R668Q, on enzymatic activity of MMP-9, measured in EBC of asthmatic children. The concentration and activity of MMP-9 were analyzed in EBC of 20 children with allergic asthma using specific standard ELISA and novel immunoenzymatic activity assay. The SNPs of MMP-9 were assessed using real-time PCR-based genotyping test. We have found that MMP-9 concentration in breath condensates of children with stable asthma was slightly higher in ELISA, than in the activity assay. Moreover, these results and activity-to-amount ratio have revealed some relationship with a presence of specific 279R and/or 668Q MMP-9 gene variants. Our observation suggests that at least in some patients MMP-9 hyperactivity may result from genetic predisposition, determined by polymorphic variants of MMP-9 gene. Moreover, it supports previous reports postulating significance of MMP-9 in pathogenesis of asthma. However, this issue still requires further studies.

Increased angiogenic factors in exhaled breath condensate of children with severe asthma - New markers of disease progression?

Asthma progression is associated with airway remodeling and neo-vascularization. However, role of angiogenesis in these changes remains unclear and available data still incomplete. In this pilot study we verify usefulness of proteome profiler assay in screening of angiogenesis-related factors in exhaled breath condensates (EBC) collected from children with asthma. EBC samples from patients with mild or severe asthma and healthy controls were tested using protein array. In EBC samples from patients with severe asthma we have found large quantities of several angiogenesis regulators, including thrombospondin (TSP)-1, angiogenin, dipeptidyl peptidase (DPP) IV, matrix metalloproteinase (MMP)-9 and its inhibitor TIMP-1. Small amounts of angiopoietin (Ang)-2 and vascular endothelial growth factor (VEGF) were also present. In contrast to them, in EBC from mild asthma group we have detected TSP-1 and small quantities of Ang-2. EBC samples from healthy controls contained only TSP-1. Our preliminary report suggests that, since increased amounts of angiogenesis-related factors in EBC seem to correlate with asthma severity, they may be considered as convenient non-invasive markers of disease progression. However, further research is necessary.

Exhaled matrix metalloproteinase 9 in patients with stable COPD - an observational study

Introduction Data on the measurement of matrix metalloproteinase 9 (MMP‑9) in exhaled breath condensate (EBC) from patients with chronic obstructive pulmonary disease (COPD) are scarce and inconsistent. Objectives We aimed to assess the usefulness of enzyme‑linked immunosorbent assay (ELISA) and immunoenzymatic assay (IEA) for the measurement of MMP‑9 in EBC, the agreement between the results of both methods, and the relationships between total and active MMP‑9 in EBC and clinical and functional COPD characteristics. Patients and methods Total (ELISA and IEA) and active (IEA) MMP‑9 levels were assessed in EBC from 70 patients with stable COPD and 21 controls and correlated with pulmonary function and COPD symptom severity. Results MMP‑9 levels did not reach the sensitivity threshold of the ELISA kit in any of the COPD patients and in 11 controls. Total and active MMP‑9 (IEA) levels did not differ between COPD patients and controls. In COPD patients, total MMP‑9 levels correlated positively with forced expiratory volume in 1 second (FEV1) and FEV1 to forced vital capacity ratio and inversely with residual volume to total lung capacity ratio. A weak positive correlation between active MMP‑9 concentrations and COPD Assessment Test (CAT) score was found (r = 0.31, P = 0.01). Conclusions The utility of ELISA in MMP‑9 assessment in EBC is limited in COPD patients, while MMP‑9 measurement in EBC by IEA is feasible. The positive correlation between active MMP‑9 and CAT score in our patients and the inverse relationship between total MMP‑9 concentration and the degree of airway obstruction reflect the complex role of MMP‑9 in COPD.