Long-term montelukast therapy in moderate to severe COPD—a preliminary observation

Montelukast, cysteinyl leukotriene receptor 1 antagonist, inhibits cardiac fibrosis by activating APJ

Montelukast, cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, is used clinically for patients with asthma, chronic obstructive pulmonary diseases (COPD), and allergic rhinitis. It has been reported that CysLT1R antagonists could reduce the risks of cardiovascular diseases in animal studies. Cardiac fibrosis is one of the major causes of heart failure. But little is known about the role of Montelukast in cardiac fibrosis and its underlying mechanism. In transverse aortic constriction (TAC) mice, Montelukast improved cardiac pumping function and inhibited cardiac fibrosis by down-regulation of the proteins related to the fibrosis, such as connective tissue growth factor (CTGF), Transforming Growth Factor β (TGF-β), and Alpha-smooth muscle actin (α-SMA). Montelukast reduced cell proliferation and collagen production in neonatal cardiac fibroblasts (CFs) with the pretreatment of 20% serum, while down-regulating the expression of TGF-β, CTGF and α-SMA. Molecules docking methods estimated a high affinity of Montelukast to Apelin receptor (APJ) and an effective chemical structure for Montelukast binding APJ. In Chinese hamster ovary (CHO) cells with stable overexpressing APJ, Montelukast inhibited forskolin (1 μM)-mediated cyclic adenosine monophosphate (cAMP) production and extracellular signal-regulated kinase1/2 (ERK1/2) phosphorylation, while these effects were reversed by pertussis toxin (PTX) pretreatment. APJ silence disrupted the effects of Montelukast in CFs pretreatment by serum 20%. So we concluded that Montelukast inhibited cardiac fibrosis due presumably to the coupling to the APJ-mediated Gi signaling pathway, which may be a promising therapeutic target for cardiac fibrosis.

Chronic obstructive pulmonary disease - diagnosis and management of stable disease; a personalized approach to care, using the treatable traits concept based on clinical phenotypes. Position paper of the Czech Pneumological and Phthisiological Society

This position paper has been drafted by experts from the Czech national board of diseases with bronchial obstruction, of the Czech Pneumological and Phthisiological Society. The statements and recommendations are based on both the results of randomized controlled trials and data from cross-sectional and prospective real-life studies to ensure they are as close as possible to the context of daily clinical practice and the current health care system of the Czech Republic. Chronic Obstructive Pulmonary Disease (COPD) is a preventable and treatable heterogeneous syndrome with a number of pulmonary and extrapulmonary clinical features and concomitant chronic diseases. The disease is associated with significant mortality, morbidity and reduced quality of life. The main characteristics include persistent respiratory symptoms and only partially reversible airflow obstruction developing due to an abnormal inflammatory response of the lungs to noxious particles and gases. Oxidative stress, protease-antiprotease imbalance and increased numbers of pro-inflammatory cells (mainly neutrophils) are the main drivers of primarily non-infectious inflammation in COPD. Besides smoking, household air pollution, occupational exposure, low birth weight, frequent respiratory infections during childhood and also genetic factors are important risk factors of COPD development. Progressive airflow limitation and airway remodelling leads to air trapping, static and dynamic hyperinflation, gas exchange abnormalities and decreased exercise capacity. Various features of the disease are expressed unequally in individual patients, resulting in various types of disease presentation, emerging as the "clinical phenotypes" (for specific clinical characteristics) and "treatable traits" (for treatable characteristics) concept. The estimated prevalence of COPD in Czechia is around 6.7% with 3,200-3,500 deaths reported annually. The elementary requirements for diagnosis of COPD are spirometric confirmation of post-bronchodilator airflow obstruction (post-BD FEV₁/VCmax <70%) and respiratory symptoms assessement (dyspnoea, exercise limitation, cough and/or sputum production. In order to establish definite COPD diagnosis, a five-step evaluation should be performed, including: 1/ inhalation risk assessment, 2/ symptoms evaluation, 3/ lung function tests, 4/ laboratory tests and 5/ imaging. At the same time, all alternative diagnoses should be excluded. For disease classification, this position paper uses both GOLD stages (1 to 4), GOLD groups (A to D) and evaluation of clinical phenotype(s). Prognosis assessment should be done in each patient. For this purpose, we recommend the use of the BODE or the CADOT index. Six elementary clinical phenotypes are recognized, including chronic bronchitis, frequent exacerbator, emphysematous, asthma/COPD overlap (ACO), bronchiectases with COPD overlap (BCO) and pulmonary cachexia. In our concept, all of these clinical phenotypes are also considered independent treatable traits. For each treatable trait, specific pharmacological and non-pharmacological therapies are defined in this document. The coincidence of two or more clinical phenotypes (i.e., treatable traits) may occur in a single individual, giving the opportunity of fully individualized, phenotype-specific treatment. Treatment of COPD should reflect the complexity and heterogeneity of the disease and be tailored to individual patients. Major goals of COPD treatment are symptom reduction and decreased exacerbation risk. Treatment strategy is divided into five strata: risk elimination, basic treatment, phenotype-specific treatment, treatment of respiratory failure and palliative care, and treatment of comorbidities. Risk elimination includes interventions against tobacco smoking and environmental/occupational exposures. Basic treatment is based on bronchodilator therapy, pulmonary rehabilitation, vaccination, care for appropriate nutrition, inhalation training, education and psychosocial support. Adequate phenotype-specific treatment varies phenotype by phenotype, including more than ten different pharmacological and non-pharmacological strategies. If more than one clinical phenotype is present, treatment strategy should follow the expression of each phenotypic label separately. In such patients, multicomponental therapeutic regimens are needed, resulting in fully individualized care. In the future, stronger measures against smoking, improvements in occupational and environmental health, early diagnosis strategies, as well as biomarker identification for patients responsive to specific treatments are warranted. New classes of treatment (inhaled PDE3/4 inhibitors, single molecule dual bronchodilators, anti-inflammatory drugs, gene editing molecules or new bronchoscopic procedures) are expected to enter the clinical practice in a very few years.

The pharmacological management of asthma-chronic obstructive pulmonary disease overlap syndrome (ACOS)

Introduction: Asthma-chronic obstructive pulmonary disease overlap syndrome (ACOS) is a disease phenotype that shares T helper lymphocyte cell Th1/neutrophilic/non-Type-2 Inflammation pathways thought to be key in COPD and Th2/eosinophilic/Type-2 inflammatory pathways of asthma. The pharmacology of treating ACOS is challenging in severe circumstances.Areas covered: This review evaluates the stepwise treatment of ACOS using pharmacological treatments used in both COPD and asthma. The most common medications involve the same inhalers used to treat COPD and asthma patients. Advanced stepwise therapies for ACOS patients are based on patient characteristics and biomarkers. Very few clinical trials exist that focus specifically on ACOS patients.Expert opinion: After inhalers, advanced therapies including phosphodiesterase inhibitors, macrolides, N-acetylcysteine and statin therapy for those ACOS patients with a COPD appearance and exacerbations are available. In atopic ACOS patients with exacerbations, advanced asthma therapies (leukotriene receptor antagonists and synthesis blocking agents.) are used. ACOS patients with elevated blood eosinophil/IgE levels are considered for immunotherapy or therapeutic monoclonal antibodies blocking specific Th2/Type-2 interleukins or IgE. Symptom control, stabilization/improvement in pulmonary function and reduced exacerbations are the metrics of success. More pharmacological trials of ACOS patients are needed to better understand which patients benefit from specific treatments.Abbreviations: 5-LOi: 5-lipoxygenase inhibitor; ACOS: asthma - COPD overlap syndrome; B₂AR: Beta₂ adrenergic receptors; cAMP: cyclic adenosine monophosphate; cGMP: cyclic guanosine monophosphate; CI: confidence interval; COPD: chronic obstructive pulmonary disease; CRS : chronic rhinosinusitis; cys-LT: cysteinyl leukotrienes; DPI: dry powder inhaler; EMA: European Medicines Agency; FDA: US Food and Drug Administration; FDC: fixed-dose combination; FeNO: exhaled nitric oxide; FEV₁: forced expiratory volume in one second; FVC: forced vital capacity; GM-CSF: granulocyte-macrophage colony-stimulating factor; ICS : inhaled corticosteroids; IL: interleukin; ILC2: Type 2 innate lymphoid cells; IP₃: Inositol triphosphate; IRR: incidence rate ratio; KOLD: Korean Obstructive Lung Disease; LABA: long-acting B₂ adrenergic receptor agonist; LAMA: long-acting muscarinic receptor antagonist; LRA: leukotriene receptor antagonist; LT: leukotrienes; MDI: metered-dose inhalers; M_N: M-subtype muscarinic receptors; MRA: muscarinic receptor antagonist; NAC: N-acetylcysteine; NEB: nebulization; OR: odds ratio; PDE: phosphodiesterase; PEFR: peak expiratory flow rate; PGD2: prostaglandin D2; PRN: as needed; RR: risk ratio; SABA: short-acting B₂ adrenergic receptor agonist; SAMA: short-acting muscarinic receptor antagonist; SDMI: spring-driven mist inhaler; Th1: T helper cell 1 lymphocyte; Th2: T helper cell 2 lymphocytes; TNF-α: tumor necrosis factor alpha; US : United States.

Does Separate Administration of Montelukast and Levocetirizine Provide Better Results in Perennial Allergic Rhinitis: A Hospital Based Study

To determine whether separate administration of Montelukast and Levocetirizine provide a better response in perennial allergic rhinitis (PAR) than their fixed dose combination. Total 151 patients underwent a hospital based clinical study, being divided in 3 discrete groups. One group was given non-bilayered combination of Montelukast and Levocetrizine, 2nd group was given their bilayered counterpart whereas 3rd group was given the drugs at 12 h interval. Medications were continued for 3 months before stoppage. All patients were followed up for 1 month more to note recurrence of symptoms of PAR on weekly basis. While the combination formulation gave 9.8 and 12.6 % symptom-free patients; separate administration of the molecules gave 43.3 % positive (symptom-free 1 month) result. Fixed-dose combination is found to cause 1.4 times more chance of recurrence. Though per se, Montelukast and Levocetrizine does not give excellent response in PAR, their separate administration provides better outcome. So a morning dose of Montelukast and Levocetirizine at bed time is recommended while treating PAR.

Prescription Status and Clinical Outcomes of Methylxanthines and Leukotriene Receptor Antagonists in Mild-to-Moderate Chronic Obstructive Pulmonary Disease

BACKGROUND

Methylxanthines and leukotriene receptor antagonists (LTRA) are not a first-line medical treatment for chronic obstructive pulmonary disease (COPD) but are frequently prescribed despite limited evidence. We aimed to elucidate the real prescribing status and clinical impacts of these agents in early COPD patients.

METHODS

Patients with mild-to-moderate COPD (FEV₁>50%) were selected from the Korean National Health and Nutrition Examination Survey data between 2007 and 2012. Besides analyzing the prescription status of methylxanthines and LTRA and the contributing factors to the prescription, we evaluated the clinical impacts of these drugs on the exacerbation, hospitalization, and medical costs.

RESULTS

Of 2269 patients with mild-to-moderate COPD, 378 patients (16.7%) were under medical treatments, and the users of methylxanthines and/or LTRA were 279 patients (12.3%); however, only 139 patients (6.1%) were inhaler users. The contributing factors for the prescription of methylxanthines were a comorbidity of asthma or allergic disease, poor lung function, low quality of life, prescribing doctor from the specialty of internal medicine, and an institution type of private hospital. The prescription of LTRA was associated with the comorbidity of allergic disease. The methylxanthine and/or LTRA users had more hospital utilization but did not have significant differences in acute exacerbations and medical cost for hospital utilization, compared with the non-users.

CONCLUSION

Methylxanthines and LTRA were used in a significant proportion of patients with mild-to-moderate COPD in real fields without favorable impacts on the exacerbations, hospitalizations, or medical costs. The use of more effective inhaled medications should be encouraged.

Eosinophils in COPD: just another biomarker?

Eosinophils are innate immune cells that, under certain conditions, can be recruited to the lungs, where they have an incompletely understood role in health and disease. Eosinophils have been found in the airways, tissues, and circulation of patients with COPD, during both stable disease and exacerbations. Epidemiological studies and post-hoc analyses of clinical trials of corticosteroid treatment for COPD have shown that the blood eosinophil count is associated with the risk of COPD exacerbations, mortality, decline in FEV₁, and response to both inhaled and systemic corticosteroids. Further studies are urgently needed to explore the contribution of eosinophils to the mechanism of disease in COPD and to identify their association with levels of clinical risk. In this review, we explore the role of the eosinophil as a biomarker and mediator of disease in COPD.

The leukotriene receptor antagonist montelukast and its possible role in the cardiovascular field

BACKGROUND

Cysteinyl leukotrienes (LTC4, LTD4, and LTE4) are pro-inflammatory mediators of the 5-lipooxygenase (5-LO) pathway, that play an important role in bronchoconstriction, but can also enhance endothelial cell permeability and myocardial contractility, and are involved in many other inflammatory conditions. In the late 1990s, leukotriene receptor antagonists (LTRAs) were introduced in therapy for asthma and later on, approved for the relief of the symptoms of allergic rhinitis, chronic obstructive pulmonary disease, and urticaria. In addition, it has been shown that LTRAs may have a potential role in preventing atherosclerosis progression.

PURPOSE

The aims of this short review are to delineate the potential cardiovascular protective role of a LTRA, montelukast, beyond its traditional use, and to foster the design of appropriate clinical trials to test this hypothesis.

RESULTS AND CONCLUSIONS

What it is known about leukotriene receptor antagonists? •Leukotriene receptor antagonist, such as montelukast and zafirlukast, is used in asthma, COPD, and allergic rhinitis. • Montelukast is the most prescribed CysLT₁ antagonist used in asthmatic patients. • Different in vivo animal studies have shown that leukotriene receptor antagonists can prevent the atherosclerosis progression, and have a protective role after cerebral ischemia. What we still need to know? • Today, there is a need for conducting clinical trials to assess the role of montelukast in reducing cardiovascular risk and to further understand the mechanism of action behind this effect.

Effects of Asian Dust Particles on the Early-Stage Antigen-Induced Immune Response of Asthma in NC/Nga Mice

Asian dust (AD) can aggravate airway inflammation in asthma, but the association between AD and the development of asthma remains unclear. This study aimed to investigate the effects of AD on the early stage of antigen sensitization using a mouse model of asthma, as well as the role of leukotrienes (LTs) in antigen-induced airway inflammation potentiated by AD particles. NC/Nga mice were co-sensitized by intranasal instillation of AD particles and/or Dermatophagoides farinae (Df) for five consecutive days. Df-sensitized mice were stimulated with an intranasal Df challenge at seven days. Mice were treated with the type 1 cysteinyl LT (CysLT₁) receptor antagonist orally 4 h before and 1 h after the allergen challenge. At 24 h post-challenge, the differential leukocyte count, inflammatory cytokines, and LTs in bronchoalveolar lavage fluid were assessed, and airway inflammation was evaluated histopathologically. AD augmented neutrophilic and eosinophilic airway inflammation with increased CysLTs and dihydroxy-LT in a mouse model of asthma. The CysLT₁ receptor antagonist was shown to attenuate both neutrophilic and eosinophilic airway inflammation augmented by AD. Therefore, exposure to AD may be associated with the development of asthma and LTs may play important roles in airway inflammation augmented by AD.

Cysteinyl leukotriene receptor-1 antagonists as modulators of innate immune cell function

Cysteinyl leukotrienes (cysLTs) are produced predominantly by cells of the innate immune system, especially basophils, eosinophils, mast cells, and monocytes/macrophages. Notwithstanding potent bronchoconstrictor activity, cysLTs are also proinflammatory consequent to their autocrine and paracrine interactions with G-protein-coupled receptors expressed not only on the aforementioned cell types, but also on Th2 lymphocytes, as well as structural cells, and to a lesser extent neutrophils and CD8⁺ cells. Recognition of the involvement of cysLTs in the immunopathogenesis of various types of acute and chronic inflammatory disorders, especially bronchial asthma, prompted the development of selective cysLT receptor-1 (cysLTR1) antagonists, specifically montelukast, pranlukast, and zafirlukast. More recently these agents have also been reported to possess secondary anti-inflammatory activities, distinct from cysLTR1 antagonism, which appear to be particularly effective in targeting neutrophils and monocytes/macrophages. Underlying mechanisms include interference with cyclic nucleotide phosphodiesterases, 5′-lipoxygenase, and the proinflammatory transcription factor, nuclear factor kappa B. These and other secondary anti-inflammatory mechanisms of the commonly used cysLTR1 antagonists are the major focus of the current review, which also includes a comparison of the anti-inflammatory effects of montelukast, pranlukast, and zafirlukast on human neutrophils in vitro, as well as an overview of both the current clinical applications of these agents and potential future applications based on preclinical and early clinical studies.

Change in asthma and COPD prescribing by Italian general practitioners between 2006 and 2008

AIMS

To explore the trend in prescribing of drugs classified within the R03 therapeutic pharmacological subgroup (drugs for obstructive airway diseases) of the Anatomical Therapeutic Chemical (ATC) classification.

METHODS

Comparison of GP-collected data on physician-patient contacts and drug prescriptions for asthma and COPD in 2006 and 2008.

RESULTS

Compared to 2006, in 2008 patients with COPD were prescribed more long-acting bronchodilators; use of tiotropium increased, whilst use of long-acting β2-agonists (LABAs) and short-acting antimuscarinic agents decreased. However, 55.9% of patients in 2006, and 47.8% in 2008, received an inhaled corticosteroid (ICS), mainly as a LABA/ICS fixed combination inhaler. Compared to 2006, in 2008 there were increased prescriptions of LABA/ICS fixed combination inhalers for asthma, but only 54.5% of all prescriptions included an ICS. This could explain the large use of short-acting β2-agonists, a marker of poor asthma control. Remarkably, LABA/ICS fixed combination inhalers were prescribed more frequently in COPD than in asthma.

CONCLUSIONS

Our data indicate that adherence to guidelines is still low. Patients with asthma and COPD are undertreated by Italian GPs, with a trend to a change in COPD prescribing likely driven by new scientific information.

Anti-inflammatory effects of montelukast on smoke-induced lung injury in rats

Aim

To evaluate the effects of montelukast in smoke-induced lung injury.

Methods

28 Wistar-Albino rats were enrolled into 4 groups with 7 rats per group. The healthy control group was exposed to fresh air while all rats in the 3 experimental groups were exposed to cigarette smoke for 20 weeks for 2 hours per day. After histopathological verification of smoke induced lung injury, montelukast (0.1 mg/kg) dissolved in Na₂CO₃ was given in one group (MON), Na₂CO₃ only was given in another group (MON control) and placebo was injected in the third group (COPD control) intraperitoneally for 21 days. At the end of this period blood samples were obtained for serum TNF-α assessment and light and electron microscopy analyses were performed on the lung tissues of sacrificed rats.

Results

Serum TNF-α levels in the MON group were significantly lower than in the MON control and COPD control groups (38.84 ± 4.9 pg/ml, 77.5 ± 5.8 pg/ml and 79.2 ± 6.9 pg/ml respectively, p < 0.05). Furthermore there was no statistically significant difference between the MON group and healthy controls with respect to serum TNF-α levels (38.84 ± 4.9 pg/ml vs. 29.5 ± 3.6 pg/ml, p > 0.05). Light and electron microscopic evaluation of the lungs demonstrated that the total histopathological damage score of the lung samples was significantly lower in the MON group than in MON controls and COPD controls (5.14 ± 0.5, 8.4 ± 0.6 and 8.7 ± 0.4 respectively, p < 0.05), while there was no significant difference between the MON group and healthy controls (5.1 ± 0.6 vs 2.3 ± 0.2, p > 0.05).

Conclusion

These findings suggest that montelukast might have a protective effect on smoke-induced lung injury in rats both from a histopathological and inflammatory point of view.

Chronic obstructive pulmonary disease: towards pharmacogenetics

Chronic obstructive pulmonary disease (COPD) is a common problem worldwide, and it is recognized that the term encompasses overlapping sub-phenotypes of disease. The development of a sub-phenotype may be determined in part by an individual's genetics, which in turn may determine response to treatment. A growing understanding of the genetic factors that predispose to COPD and its sub-phenotypes and the pathophysiology of the condition is now leading to the suggestion of individualized therapy based on the patients' clinical phenotype and genotype. Pharmacogenetics is the study of variations in treatment response according to genotype and is perhaps the next direction for genetic research in COPD. Here, we consider how knowledge of the pathophysiology and genetic risk factors for COPD may inform future management strategies for affected individuals.

Leukotriene C4 synthase and ischemic cardiovascular disease and obstructive pulmonary disease in 13,000 individuals

Ischemic cardiovascular disease and obstructive pulmonary disease involve inflammation. Leukotrienes may be important pro-inflammatory mediators. We tested the hypothesis that the (-1072)G > A and (-444)A > C promoter polymorphisms of leukotriene C4 synthase confer risk of transient ischemic attack (TIA), ischemic stroke, ischemic heart disease (IHD), asthma, and chronic obstructive pulmonary disease (COPD). We genotyped individuals from the Danish general population, the Copenhagen City Heart Study, and Danish patients with IHD/coronary atherosclerosis, the Copenhagen Ischemic Heart Disease Study. We used prospective (n = 10,386), cross-sectional (n = 10,386), and case-control (n = 2392 + 5012) designs. Allele frequency was 0.07 for (-1072)A and 0.29 for (-444)C. Cumulative incidence for TIA was higher for (-1072)AA versus GG genotype (log-rank: p < 0.001), and lower for (-444)CC versus AA genotype (log-rank: p = 0.03). Cumulative incidence for ischemic stroke was also lower for (-444)CC versus AA genotype (log-rank: p = 0.04). Multifactorially adjusted hazard ratios for TIA were 5.2(95% CI:1.9-14) for (-1072)AA versus GG genotype, and 0.4(0.2-1.0) for (-444)CC versus AA genotype. Corresponding values were 1.9 (0.7-5.2) and 0.7 (0.5-1.0) for ischemic stroke, and 0.8 (0.4-1.6) and 1.0 (0.9-1.2) for IHD. In the case-control study, corresponding multifactorially adjusted odds ratios for IHD/coronary atherosclerosis were 0.5 (0.2-1.3) and 1.2 (1.0-1.5). These genotypes were not associated with risk of asthma or COPD. Leukotriene C4 synthase promoter genotypes influence risk of TIA and ischemic stroke, but not risk of IHD/coronary atherosclerosis, asthma, or COPD.

Potential role of leukotriene modifiers in the treatment of chronic obstructive pulmonary disease

Abstract Chronic obstructive pulmonary disease (COPD) is characterized by progressive, irreversible airflow limitation coupled with an abnormal inflammatory process. It is associated with high morbidity and mortality. Leukotriene modifiers, approved by the United States Food and Drug Administration as treatment for asthma and allergic rhinitis, may also alleviate the abnormal inflammatory response seen in patients with COPD. To explore the outcomes of research in this area, we conducted a literature search from 1950-2007, using the PubMed database. We found no published studies that provided conclusive evidence that the available leukotriene modifiers benefit patients with COPD. However, data do suggest that leukotriene modifiers may offer benefits to patients with COPD, including effects that pertain to airflow limitation, neutrophil and lymphocyte chemotaxis, and neutrophil longevity. Added to conventional treatment, these agents appear to reduce symptoms, improve objective measures of disease, and control inflammation. Further studies are needed to determine the precise role of leukotriene modifiers in the treatment of COPD.

Montelukast inhibits neutrophil pro-inflammatory activity by a cyclic AMP-dependent mechanism

BACKGROUND AND PURPOSE

The objective of this study was to characterize the effects of the cysteinyl leukotriene receptor antagonist, montelukast (0.1-2 micromol x L(-1)), on Ca(2+)-dependent pro-inflammatory activities, cytosolic Ca(2+) fluxes and intracellular cAMP in isolated human neutrophils activated with the chemoattractants, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (1 micromol x L(-1)) and platelet-activating factor (200 nmol x L(-1)).

EXPERIMENTAL APPROACH

Generation of reactive oxygen species was measured by lucigenin- and luminol-enhanced chemiluminescence, elastase release by a colourimetric assay, leukotriene B(4) and cAMP by competitive binding ELISA procedures, and Ca(2+) fluxes by fura-2/AM-based spectrofluorimetric and radiometric ((45)Ca(2+)) procedures.

KEY RESULTS

Pre-incubation of neutrophils with montelukast resulted in dose-related inhibition of the generation of reactive oxygen species and leukotriene B(4) by chemoattractant-activated neutrophils, as well as release of elastase, all of which were maximal at 2 micromol x L(-1) (mean percentages of the control values of 30 +/- 1, 12 +/- 3 and 21 +/- 3 respectively; P < 0.05). From a mechanistic perspective, treatment of chemoattractant-activated neutrophils with montelukast resulted in significant reductions in both post-peak cytosolic Ca(2+) concentrations and store-operated Ca(2+) influx. These montelukast-mediated alterations in Ca(2+) handling by the cells were associated with a significant elevation in basal cAMP levels, which resulted from inhibition of cyclic nucleotide phosphodiesterases.

CONCLUSIONS AND IMPLICATIONS

Montelukast, primarily a cysteinyl leukotriene (CysLT(1)) receptor antagonist, exhibited previously undocumented, secondary, neutrophil-directed anti-inflammatory properties, which appeared to be cAMP-dependent.

Cysteinyl-leukotrienes and their receptors in asthma and other inflammatory diseases: critical update and emerging trends

Cysteinyl-leukotrienes (cysteinyl-LTs), that is, LTC4, LTD4, and LTE4, trigger contractile and inflammatory responses through the specific interaction with G protein-coupled receptors (GPCRs) belonging to the purine receptor cluster of the rhodopsin family, and identified as CysLT receptors (CysLTRs). Cysteinyl-LTs have a clear role in pathophysiological conditions such as asthma and allergic rhinitis (AR), and have been implicated in other inflammatory conditions including cardiovascular diseases, cancer, atopic dermatitis, and urticaria. Molecular cloning of human CysLT1R and CysLT2R subtypes has confirmed most of the previous pharmacological characterization and identified distinct expression patterns only partially overlapping. Interestingly, recent data provide evidence for the immunomodulation of CysLTR expression, the existence of additional receptor subtypes, and of an intracellular pool of CysLTRs that may have roles different from those of plasma membrane receptors. Furthermore, genetic variants have been identified for the CysLTRs that may interact to confer risk for atopy. Finally, a crosstalk between the cysteinyl-LT and the purine systems is being delineated. This review will summarize and attempt to integrate recent data derived from studies on the molecular pharmacology and pharmacogenetics of CysLTRs, and will consider the therapeutic opportunities arising from the new roles suggested for cysteinyl-LTs and their receptors.

One hundred years of chronic obstructive pulmonary disease (COPD)

Chronic obstructive pulmonary disease (COPD) is an increasing health problem and one of the leading causes of morbidity and mortality worldwide, but knowledge about its pathogenesis has increased substantially in recent years. The disease results from interaction between individual risk factors (like enzymatic deficiencies) and environmental exposures to noxious agents, like cigarette smoking, occupational dusts, air pollution and infections in childhood. The main mechanisms that may contribute to airflow limitation in COPD are fixed narrowing of small airways, emphysema and luminal obstruction with mucus secretions. COPD is characterised by a chronic inflammatory process in the pulmonary tissue, with a pattern different from bronchial asthma, associated with extrapulmonary effects and is considered now a complex, systemic disease. Optimal therapeutic targeting of COPD depends on a clear understanding of the precise mechanisms of these complex processes and on early and correct evaluation of disease severity. A combination of pharmacological and non-pharmacological approaches is used to treat COPD. Bronchodilators are the mainstay of COPD treatment and can be combined with inhaled corticosteroids for greater efficacy and fewer side effects. The use of LTOT for hypoxemic patients has resulted in increased survival, and expanded drug therapy options have effectively improved dyspnoea and quality of life. Recent studies have documented the benefits of pulmonary rehabilitation. In addition, non-invasive mechanical ventilation offers new alternatives for patients with acute or chronic failure.

Leukotriene E(4) in urine in patients with asthma and COPD--the effect of smoking habit

Leukotriene E(4) (LTE(4)) is implicated in asthma pathophysiology and possibly in chronic obstructive pulmonary disease (COPD) as one of the causes of persistent bronchoconstriction and mucus hypersecretion. Cigarette smoking stimulates cysteinyl leukotrienes (CysLTs) production. We investigated whether LTE(4) is equally increased in asthma and COPD and whether smoking significantly affects LTE(4) levels. Secondary outcomes involved correlations with inflammatory and functional parameters. We studied 40 patients with COPD [20 smokers], 40 asthmatics [20 smokers] and 30 healthy subjects [15 smokers]. Spirometry (FEV(1)% pred., FEV(1)/FVC) was performed, urine was collected for measurement of LTE(4) and creatinine, induced sputum was collected for differential cell counts and serum for ECP. LTE(4)/creatinine levels (pg/mg) [mean (sd)] were increased in asthmatic patients compared to COPD and controls, [125.6(54.5) vs. 54.5(19) vs. 55.9(18.9)pg/mg, respectively, P<0.0001 for asthma]. Smoking significantly affects LTE(4) levels only in asthmatic patients [164 (48) vs. 87 (26.3), P<0.0001 for smokers]. The only significant correlation was between eosinophils in induced sputum and LTE(4)/creatinine levels in asthmatics. In conclusion, patients with asthma presented higher LTE(4) values compared to normals and patients with COPD. Smoking significantly affects LTE(4) values only in asthmatics indicating a different underlying CysLTs inflammatory process in this condition.

Mediators of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major and increasing global health problem that is now a leading cause of death. COPD is associated with a chronic inflammatory response, predominantly in small airways and lung parenchyma, which is characterized by increased numbers of macrophages, neutrophils, and T lymphocytes. The inflammatory mediators involved in COPD have not been clearly defined, in contrast to asthma, but it is now apparent that many lipid mediators, inflammatory peptides, reactive oxygen and nitrogen species, chemokines, cytokines, and growth factors are involved in orchestrating the complex inflammatory process that results in small airway fibrosis and alveolar destruction. Many proteases are also involved in the inflammatory process and are responsible for the destruction of elastin fibers in the lung parenchyma, which is the hallmark of emphysema. The identification of inflammatory mediators and understanding their interactions is important for the development of anti-inflammatory treatments for this important disease.

Short-term effects of montelukast in stable patients with moderate to severe COPD

This study aims to investigate the possibility of additional value of leukotriene receptor antagonist (LTA) on dyspnea score, arterial blood gases (ABG), pulmonary function tests (PFTs), and quality of life (St. George QoL) in chronic obstructive pulmonary disease (COPD) patients. In this randomized, prospective, single-blind, and controlled study, 117 non-reversible COPD patients defined by global initiative for chronic obstructive lung disease (GOLD) criteria were randomized to receive ipratropium bromide, formoterol and montelukast (n:58, montelukast group) or ipratropium bromide and formoterol (n:59, control group) after a 2-week run-in period. There was no significant demographic difference between the two groups (P>0.05). Baseline ABG, PFT, visual analoque scores (VAS), and QoL scores were obtained and at first month and second month, PFT, VAS, and QoL scores were repeated and ABG was obtained at second month and the values were compared with baseline values. As the result of the comparison, there was significant increase in vital capacity, FVC, FEV1, VAS, and PaO2 parameters (P<0.05), and a significant decrease in the QoL scores (P<0.05) in the montelukast group. These parameters did not show any difference in the control group (P>0.05). Sputum samples that could be obtained in 24 of the COPD patients were evaluated and in the montelukast group, there was a decrease in neutrophilic activity after treatment (n:13) (P:0.059). These results suggest that LTA that is used additionally in routine treatment protocol can produce additive improvement on PFT, dyspnea score and especially QoL in patients with stable COPD and for these reasons, LTA may be taken into account when there is need for an additional anti-inflammatory treatment in COPD patients.

Enfermedad pulmonar obstructiva crónica

Treatment of chronic obstructive pulmonary disease (COPD) has underwent a very important advance in the last five years. It has been developed a new long-lasting anticholynergic drug, tiotrope bromure, which has been found to improve lung function and exercise capacity and to decrease relapses. Also the combined treatment of long lasting beta 2 adrenergics with inhaled steroids (salmeterol/fluticasone and formoterol/budesonide) has proven similar results. However, the response to these new drugs is not the same in all patients. Individual characteristics such as gravity, degree of bronchial hyperresponsiveness, frequency of relapses, comorbidity, etc will determine the response to several agents. Thus, it is necessary to perform a detailed diagnostic study in COPD patients in order to select the best treatment in an individualized form. In the future, new specific antiinflammatories such as phosphodiesterase 4 inhibitors or agents with a potential action in tissue regeneration could lead to new perspectives, as well as to new questions, in COPD treatment.