Long-acting beta-agonists: anti-inflammatory properties and synergy with corticosteroids in asthma

Drug-Drug Interactions and Synergy: From Pharmacological Models to Clinical Application

This review explores the concept of synergy in pharmacology, emphasizing its importance in optimizing treatment outcomes through the combination of drugs with different mechanisms of action. Synergy, defined as an effect greater than the expected additive effect elicited by individual agents according to specific predictive models, offers a promising approach to enhance therapeutic efficacy while minimizing adverse events. The historical evolution of synergy research, from ancient civilizations to modern pharmacology, highlights the ongoing quest to understand and harness synergistic interactions. Key concepts, such as concentration-response curves, additive effects, and predictive models, are discussed in detail, emphasizing the need for accurate assessment methods throughout translational drug development. Although various mathematical models exist for synergy analysis, selecting the appropriate model and software tools remains a challenge, necessitating careful consideration of experimental design and data interpretation. Furthermore, this review addresses practical considerations in synergy assessment, including preclinical and clinical approaches, mechanism of action, and statistical analysis. Optimizing synergy requires attention to concentration/dose ratios, target site localization, and timing of drug administration, ensuring that the benefits of combination therapy detected bench-side are translatable into clinical practice. Overall, the review advocates for a systematic approach to synergy assessment, incorporating robust statistical analysis, effective and simplified predictive models, and collaborative efforts across pivotal sectors, such as academic institutions, pharmaceutical companies, and regulatory agencies. By overcoming critical challenges and maximizing therapeutic potential, effective synergy assessment in drug development holds promise for advancing patient care. SIGNIFICANCE STATEMENT: Combining drugs with different mechanisms of action for synergistic interactions optimizes treatment efficacy and safety. Accurate interpretation of synergy requires the identification of the expected additive effect. Despite innovative models to predict the additive effect, consensus in drug-drug interactions research is lacking, hindering the bench-to-bedside development of combination therapies. Collaboration among science, industry, and regulation is crucial for advancing combination therapy development, ensuring rigorous application of predictive models in clinical settings.

Treatment response heterogeneity in asthma: the role of genetic variation

INTRODUCTION

Asthmatic patients show a large heterogeneity in response to asthma medication. Rapidly evolving genotyping technologies have led to the identification of various genetic variants associated with treatment outcomes. Areas covered: This review focuses on the current knowledge of genetic variants influencing treatment response to the most commonly used asthma medicines: short- and long-acting beta-2 agonists (SABA/LABA), inhaled corticosteroids (ICS) and leukotriene modifiers. This review shows that various genetic variants have been identified, but none are currently used to guide asthma treatment. One of the most promising genetic variants is the Arg16 variant in the ADRB2 gene to guide LABA treatment in asthmatic children. Expert commentary: Poor replication of initially promising results and the low fraction of variability accounted for by single genetic variants inhibit pharmacogenetic findings to reach the asthma clinic. Nevertheless, the identification of genetic variation influencing treatment response does provide more insights in the complex processes underlying response and might identify novel targets for treatment. There is a need to report measures of clinical validity, to perform precision-medicine guided trials, as well as to understand how genetic variation interacts with environmental factors. In addition, systems biology approaches might be able to show a more complete picture of these complex interactions.

Vilanterol and fluticasone furoate for asthma

BACKGROUND

Vilanterol (VI) is a long-acting beta2-agonist (LABA) that binds to the beta2-adrenoceptor on the airway smooth muscle, producing bronchodilation. LABA therapy, which is well established in adults as part of the British Thoracic Society (BTS) Guidelines for the Management of Asthma, leads to improvement in symptoms and lung function and reduction in exacerbations. At present, the commonly used LABAs licensed for use in asthma management (formoterol and salmeterol) require twice-daily administration, whereas VI is a once-daily therapy.Fluticasone furoate (FF) is an inhaled corticosteroid (ICS), and ICS therapy is recommended by the BTS asthma guidelines. ICSs, the mainstay of asthma treatment, lead to a reduction in both airway inflammation and airway hyper-responsiveness. Regular use leads to improvement in symptoms and lung function. ICSs are currently recommended as 'preventer' therapy for patients who use a 'reliever' medication (e.g. short-acting beta2 agonist (SABA), salbutamol) three or more times per week. Most of the commonly used ICS treatments are twice-daily medications, although two once-daily products are currently licensed (ciclesonide and mometasone).At the present time, only one once-daily ICS/LABA combination (FF/VI) is available, and several other combination inhalers are recommended for twice-daily administration.

OBJECTIVES

To compare effects of VI and FF in combination versus placebo, or versus other ICSs and/or LABAs, on acute exacerbations and on health-related quality of life (HRQoL) in adults and children with chronic asthma.

SEARCH METHODS

We searched the Cochrane Airways Group Register of trials, clinical trial registries, manufacturers' websites and reference lists of included studies up to June 2016.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of adults and children with a diagnosis of asthma. Included studies compared VI and FF combined versus placebo, or versus other ICSs and/or LABAs. Our primary outcomes were health-related quality of life, severe asthma exacerbation, as defined by hospital admissions or treatment with a course of oral corticosteroids, and serious adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and analysed outcomes using a fixed-effect model. We used standard Cochrane methods.

MAIN RESULTS

We identified 14 studies that met our inclusion criteria, with a total of 6641 randomised participants, of whom 5638 completed the study. All studies lasted between two and 78 weeks and showed good methodological quality overall.We included 10 comparisons in this review, seven for which the dose of VI and FF was 100/25 mcg (VI/FF 100/25 mcg vs placebo; VI/FF 100/25 mcg vs same dose of FF; VI/FF 100/25 mcg vs same dose of VI; VI/FF 100/25 mcg vs fluticasone propionate (FP) 500 mcg twice-daily; VI/FF 100/25 mcg vs fluticasone propionate/salmeterol (FP/SAL) 250/50 mcg twice-daily; VI/FF 100/25 mcg vs FP/SAL 250/25 mcg twice-daily; FF/VI 100/25 vs FP/SAL500/50) and three for which the dose of VI and FF was 200/25 mcg (VI/FF 200/25 mcg vs placebo; VI/FF 200/25 mcg vs FP 500 mcg; VI/FF 200/25 mcg vs same dose of FF).We found very few opportunities to combine results from the 14 included studies in meta-analyses. We tabulated the data for our pre-specified primary outcomes. In particular, we found insufficient information to assess whether once-daily VI/FF was better or worse than twice-daily FP/SAL in terms of efficacy or safety.Only one of the 14 studies looked at health-related quality of life when comparing VI and FF 100/25 mcg versus placebo and identified a significant advantage of VI/FF 100/25 mcg (mean difference (MD) 0.30, 95% confidence interval (CI) 0.14 to 0.46; 329 participants); we recognised this as moderate-quality evidence. Only two studies compared VI/FF 100/25 mcg versus placebo with respect to exacerbations; both studies reported no exacerbations in either treatment arm. Five studies (VI/FF 100/25 mcg vs placebo) sought information on serious adverse events; all five studies reported no serious adverse events in the VI/FF 100/25 mcg or placebo arms. We found no comparison relevant to our primary outcomes for VI/FF at a higher dose (200/25 mcg) versus placebo.The small number of studies contributing to each comparison precludes the opportunity to draw robust conclusions for clinical practice. These studies were not of sufficient duration to allow conclusions about long-term side effects.

AUTHORS' CONCLUSIONS

Some evidence suggests clear advantages for VI/FF, in combination, compared with placebo, particularly for forced expiratory volume in one second (FEV1) and peak expiratory flow; however, the variety of questions addressed in the included studies did not allow review authors to draw firm conclusions. Information was insufficient for assessment of whether once-daily VI/FF was better or worse than twice-daily FP/SAL in terms of efficacy or safety. It is clear that more research is required to reduce the uncertainties that surround interpretation of these studies. It will be necessary for these findings to be replicated in other work before more robust conclusions are revealed. Only five of the 13 included studies provided data on health-related quality of life, and only six recorded asthma exacerbations. Only one study focused on paediatric patients, so no conclusions can be drawn for the paediatric population. More research is needed, particularly in the primary outcome areas selected for this review, so that we can draw firmer conclusions in the next update of this review.

Therapeutic effect of budesonide/formoterol, montelukast and N-acetylcysteine for bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation

Background

Bronchiolitis obliterans syndrome (BOS) after allogeneic hematopoietic stem cell transplantation (HSCT) is currently treated with systemic corticosteroids despite poor efficacy and side effects. This study investigated the therapeutic effect of budesonide/formoterol, montelukast and n-acetylcysteine, which are suggested as treatment options for BOS after HSCT.

Methods

After diagnosis of BOS, 61 patients were treated with budesonide/formoterol, montelukast and n-acetylcysteine for 3 months. Pulmonary function test and COPD assessment test (CAT) were performed before and after the combination therapy. Therapeutic response was evaluated by changes in forced expiratory volume in 1 s (FEV₁) or CAT score.

Results

After 3 months of combination treatment, mean FEV₁ increased by 220 mL (p < 0.001) and residual volume decreased by 200 mL (p =0 .005). Median CAT score also significantly decreased from 15.5 to 11.0 (p = 0.001). The overall response rate to combination therapy was 82 %. Comparing the no-response group and the response group, the forced vital capacity (% predicted) decline between pre-HSCT and BOS diagnosis was significantly greater in the response group (p = 0.036).

Conclusion

Combination treatment with budesonide/formoterol, montelukast and n-acetylcysteine significantly improved lung function and respiratory symptoms in patients with BOS after allogeneic HSCT without serious side effects.

Chronic obstructive pulmonary disease associated with increased risk of bipolar disorder

Epidemiological studies have identified a trend in the development of depressive and anxiety disorders following a diagnosis of chronic obstructive pulmonary disease (COPD). However, the relationship between COPD and subsequent bipolar disorder remains unclear. From January 1, 2000, we identified adult patients with COPD from the Taiwan National Health Insurance Research Database. A nationwide population-based study was conducted; 46,778 COPD patients and 46,778 age-, sex-, and comorbidity-matched subjects between 2000 and 2011 were enrolled. The two cohorts were followed up till December 31, 2011 and observed for occurrence of bipolar disorder. We observed the COPD and comparison cohorts for 263,020 and 267,895 person-years, respectively, from 2000 to 2011. The incidence rate for bipolar disorder was 1.6/1000 person-years in the COPD cohort and 1.2/1000 person-years in the comparison cohort ( p < 0.001). After multivariate adjustment, the hazard ratio (HR) for subsequent bipolar disorder among the COPD patients was 1.42 (95% confidence interval [CI], 1.22-1.64; p < 0.001). In the COPD patients, short-acting beta-agonists (SABAs) was associated with a significantly increased risk of bipolar disorder development (HR = 1.83, 95% CI = 1.25-2.69, p = 0.002). Other COPD medications were not associated with the risk of bipolar disorder development. The study results indicate that COPD may be an independent risk factor for the development of bipolar disorder. The regular use of SABAs might increase the risk of bipolar disorder in COPD patients.

A-kinase-anchoring proteins coordinate inflammatory responses to cigarette smoke in airway smooth muscle

β2-Agonist inhibitors can relieve chronic obstructive pulmonary disease (COPD) symptoms by stimulating cyclic AMP (cAMP) signaling. A-kinase-anchoring proteins (AKAPs) compartmentalize cAMP signaling by establishing protein complexes. We previously reported that the β2-agonist fenoterol, direct activation of protein kinase A (PKA), and exchange factor directly activated by cAMP decrease cigarette smoke extract (CSE)-induced release of neutrophil attractant interleukin-8 (IL-8) from human airway smooth muscle (ASM) cells. In the present study, we tested the role of AKAPs in CSE-induced IL-8 release from ASM cells and assessed the effect of CSE on the expression levels of different AKAPs. We also studied mRNA and protein expression of AKAPs in lung tissue from patients with COPD. Our data show that CSE exposure of ASM cells decreases AKAP5 and AKAP12, both capable of interacting with β2-adrenoceptors. In lung tissue of patients with COPD, mRNA levels of AKAP5 and AKAP12 were decreased compared with lung tissue from controls. Using immunohistochemistry, we detected less AKAP5 protein in ASM of patients with COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage II compared with control subjects. St-Ht31, which disrupts AKAP-PKA interactions, augmented CSE-induced IL-8 release from ASM cells and diminished its suppression by fenoterol, an effect mediated by disturbed ERK signaling. The modulatory role of AKAP-PKA interactions in the anti-inflammatory effects of fenoterol in ASM cells and the decrease in expression of AKAP5 and AKAP12 in response to cigarette smoke and in lungs of patients with COPD suggest that cigarette smoke-induced changes in AKAP5 and AKAP12 in patients with COPD may affect efficacy of pharmacotherapy.

Budesonide/formoterol maintenance and reliever therapy in asthma control: acute, dose-related effects and real-life effectiveness

BACKGROUND AND OBJECTIVE

The efficacy of budesonide/formoterol maintenance and reliever therapy (BFMRT) in asthma control is well documented in large randomized controlled trials. However, the acute reliever effects and real-life effectiveness are seldom reported.

METHODS

This multicenter trial enrolled steroid-naïve, symptomatic asthmatics with baseline exhaled nitric oxide (eNO) of ≥ 40 ppb. There were 120 eligible patients who were randomized and received a dose of inhaled budesonide/formoterol 320/9 μg (lower dose budesonide/formoterol), 640/18 μg (higher dose budesonide/formoterol (HDBF)), or terbutaline (TERB) 1 mg. Inflammatory cells and mediators in induced sputum, eNO and lung function were measured at baseline and 6 h (acute phase). Subsequently, all patients used BFMRT as real-life practice for 24 weeks (maintenance phase).

RESULTS

In the acute phase, the degree of post-treatment reduction in total eosinophil counts, interleukin-8 and matrix metalloproteinase-9 in induced sputum were significantly greater in group HDBF (vs TERB, P < 0.05). The increase in forced expiratory volume in first second (FEV1 ) in group HDBF was significantly higher (vs LDBF and TERB, P < 0.05) 3 h after dosing. In the maintenance phase, significant improvement of asthma control (presented by eNO, FEV1 and a five-item asthma control questionnaire) in real-life settings was observed at 4 weeks and sustained to the end of study. The rate of patients who followed scheduled visits declined over time (87% at week 4 and 42% at week 24).

CONCLUSIONS

Budesonide/formoterol as reliever exerts acute, dose-related anti-inflammatory effects and FEV1 improvement in symptomatic asthmatics. BFMRT is effective in asthma control. However, the decrease in long-term follow-up rate remains an issue to overcome in real-life settings.

Chronic treatment in vivo with β-adrenoceptor agonists induces dysfunction of airway β(2) -adrenoceptors and exacerbates lung inflammation in mice

BACKGROUND AND PURPOSE

Inhalation of a β-adrenoceptor agonist (β-agonist) is first-line asthma therapy, used for both prophylaxis against, and acute relief of, bronchoconstriction. However, repeated clinical use of β-agonists leads to impaired bronchoprotection and, in some cases, adverse patient outcomes. Mechanisms underlying this β(2) -adrenoceptor dysfunction are not well understood, due largely to the lack of a comprehensive animal model and the uncertainty as to whether or not bronchorelaxation in mice is mediated by β(2) -adrenoceptors. Thus, we aimed to develop a mouse model that demonstrated functional β-agonist-induced β(2) -adrenoceptor desensitization in the context of allergic inflammatory airway disease.

EXPERIMENTAL APPROACH

We combined chronic allergen exposure with repeated β-agonist inhalation in allergen-treated BALB/C mice and examined the contribution of β(2) -adrenoceptors to albuterol-induced bronchoprotection using FVB/NJ mice with genetic deletion of β(2) -adrenoceptors (KO). Associated inflammatory changes - cytokines (ELISA), cells in bronchoalevolar lavage and airway remodelling (histology) and β(2) -adrenoceptor density (radioligand binding) - were also measured. KEY RESULTS β(2) -Adrenoceptors mediated albuterol-induced bronchoprotection in mice. Chronic treatment with albuterol induced loss of bronchoprotection, associated with exacerbation of the inflammatory components of the asthma phenotype.

CONCLUSIONS AND IMPLICATIONS

This animal model reproduced salient features of human asthma and linked loss of bronchoprotection with airway pathobiology. Accordingly, the model offers an advanced tool for understanding the mechanisms of the effects of chronic β- agonist treatment on β-adrenoceptor function in asthma. Such information may guide the clinical use of β-agonists and provide insight into development of novel β-adrenoceptor ligands for the treatment of asthma.

Additive anti-inflammatory effects of beta 2 adrenoceptor agonists or glucocorticosteroid with roflumilast in human peripheral blood mononuclear cells

The phosphodiesterase 4 inhibitor (PDE4i) roflumilast has been approved in the US and EU for treatment of GOLD stage 3 and 4 chronic obstructive pulmonary disease (COPD). Inhaled β2 adrenoceptor agonist bronchodilators and anti-inflammatory glucocorticosteroids are also used as standard of care in COPD. We investigated the anti-inflammatory interaction of roflumilast in combination with long-acting β2 agonists (LABA), salmeterol or formoterol, or a glucocorticosteroid, dexamethasone, on cytokine production from LPS-stimulated human primary peripheral blood mononuclear cells (PBMC). Salmeterol or formoterol caused a concentration-dependent inhibition of tumor necrosis factor-α (TNFα) secretion with an IC50 of 0.33 pM (C.I. 0.006-19) and 34 pM (C.I. 13-87), respectively. When roflumilast was evaluated, the addition of salmeterol (1 nM) to roflumilast caused the IC50 for roflumilast to shift from 1.8 nM (C.I. 0.8-4) to 4.1 pM (C.I.0.3-69) (p < 0.01), and maximal inhibition increased from 72.5 ± 3.2% to 90.9 ± 3.1%. Addition of formoterol to roflumilast also produced an increased TNFα inhibition more than either drug alone (p < 0.05). The inhibition of TNFα production with salmeterol was both β2 adrenoceptor- and protein kinase A-dependent. Addition of roflumilast (10 nM) in the presence of dexamethasone increased the inhibition of LPS-induced TNFα and CCL3. Roflumilast in combination with salmeterol, formoterol, or dexamethasone increased the inhibition of LPS-induced TNFα from human PBMC, in an additive manner. Addition of roflumilast to either a β2 adrenoceptor agonist or a glucocorticosteroid may provide superior anti-inflammatory activity and greater efficacy in COPD patients and be dose sparing.

Modulation of 11β-hydroxysteroid dehydrogenase 1 by β2-adrenoceptor in the ischaemia-reperfused rat kidney

BACKGROUND

11β-Hydroxysteroid dehydrogenase Type 1 (11βHSD-1) amplifies intracellular levels of active glucocorticoids which possess protective effects against organ ischaemia and reperfusion (I/R). However, the mechanisms by which 11βHSD-1 is modified after a renal I/R challenge remain unclear. This study investigated the effect of β(2)-adrenoceptor (β(2)-AR) activation and the subsequent signalling pathways on renal 11βHSD-1 gene expression following renal I/R.

METHODS

Renal I/R was induced using 25 min of bilateral renal artery occlusion in 4-week-old Wistar rats followed by an intraperitoneal injection of various doses of adeno-β(2)-AR gene. Following renal I/R, kidneys, plasma and urine were collected to assay 11βHSD messenger RNA (mRNA) levels, β(2)-AR signalling cascades and renal function.

RESULTS

On the second day after the renal I/R challenge, there was a reduction in renal 11βHSD-1 mRNA levels associated with a decrease in stimulatory G protein α (Gsα) and adenylate cyclase-1 (ACY-1) in the kidney. The addition of the adeno-β(2)-AR gene resulted in greater increases in 11βHSD-1 mRNA and β(2)-AR-Gsα-ACY-cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) activity in the kidney but had no effect on 11βHSD-2 mRNA or protein kinase C levels in the kidney.

CONCLUSIONS

Over-expression of β(2)-AR resulting from the gene delivery improved renal function and 11βHSD-1 production following renal I/R, which were actions exerted through the cAMP-PKA pathway. The stimulatory effect of functional β(2)-AR activation on renal 11βHSD-1 expression may offer a means of protection from renal I/R injury.

New perspectives regarding β(2) -adrenoceptor ligands in the treatment of asthma

In the last two decades several significant changes have been proposed in the receptor theory that describes how ligands can interact with G protein-coupled receptors (GPCRs). Here we briefly summarize the evolution of receptor theory and detail recent prominent advances. These include: (i) the existence of spontaneously active GPCRs that are capable of signalling even though they are unoccupied by any ligand; (ii) the discovery of ligands that can inactivate these spontaneously active receptors; (iii) the notion that a ligand may simultaneously activate more than one GPCR signalling pathway; and (iv) the notion that certain ligands may be able to preferentially direct receptor signalling to a specific pathway. Because the data supporting these receptor theory ideas are derived primarily from studies using artificial expression systems, the physiological relevance of these new paradigms remains in question. As a potential example of how these new perspectives in receptor theory relate to drug actions and clinical outcomes, we discuss their relevance to the recent controversy regarding the chronic use of β(2) -adrenoceptor agonists in the treatment of asthma.

Budesonide/formoterol dry powder in asthma: an option for control as maintenance and reliever therapy

IMPORTANCE OF THE FIELD

Asthma is a heterogeneous disease with various components that may contribute to symptoms. Obtaining global control of is one of the fundamental parts of the management of this disease.

AREAS COVERED IN THIS REVIEW

The Cochrane trial database, Medline and Embase, were searched systematically, and approximately 20 respiratory journals and conference abstracts were searched manually. The search was limited to publications in English language of last 20 years and which included the keywords 'budesonide', 'formoterol', 'asthma' and 'control'.

WHAT THE READER WILL GAIN

The purposes of this review are: i) to discuss the rationale about possibility of using combination therapy administered with a single inhaler for both daily maintenance and relief as needed of breakthrough symptoms in asthma management; ii) to give readers the current status of clinical pharmacological treatment of asthma; iii) to discuss the evidence on the use of budesonide/formoterol dry powder in one inhaler.

TAKE HOME MESSAGE

Among the various inhalatory drugs, budesonide and formoterol can be conveniently delivered in one dry powder inhaler and simplify treatment by providing immediate step-up when symptoms increase. Alongside the anti-inflammatory component, formoterol provides both short- and long-acting bronchodilator effects with maintenance and reliever properties. The option of using one inhaler simplifies treatment by simultaneously providing bronchodilator and anti-inflammatory activity, thus enhancing compliance. As indicated in guidelines, all these characteristics are essential for optimizing asthma treatment and control.

[Prospective evaluation of the efficacy of the combination of budesonide/formoterol in obstructive airway disease after allogeneic hematopoietic stem cell transplantation]

État des connaissances

La survenue d’un trouble ventilatoire obstructif au décours d’une allogreffe de cellules souches hématopoïétiques est attribuée à une réaction de greffon contre l’hôte pulmonaire et menace le pronostic des patients. La prise en charge thérapeutique consiste habituellement en une intensification du traitement immunosuppresseur systémique. Cette attitude non validée entraîne de nombreuses complications, notamment infectieuses, encourageant l’évaluation de traitements plus ciblés. Nous avons récemment rapporté de façon rétrospective notre expérience de l’efficacité du budésonide/ formotérol inhalés dans cette pathologie.

Méthodes

Il s’agit d’une étude prospective, multicentrique, randomisée, en double aveugle contre placebo qui évaluera l’efficacité de l’association budésonide/formotérol (400/12 µg 2 inhalations matin et soir) chez des patients ayant développé un trouble ventilatoire obstructif modéré à sévère après allogreffe de cellules souches hématopoïétiques. Le critère d’évaluation principal sera la variation absolue du VEMS après 1 mois de traitement. Les critères d’évaluation secondaires seront basés sur l’évolution de la symptomatologie clinique et de la fonction respiratoire après 6 mois de traitement.

Résultats attendus

L’hypothèse émise est que le traitement inhalé de budésonide/formotérol améliore de façon significative la fonction et les symptômes respiratoires dès le premier mois de traitement dans le groupe de patients étudié.

Is elevated noradrenaline an aetiological factor in a number of diseases?

1 Here I put forth the hypothesis that noradrenaline (NA), which is a signalling molecule in the brain and sympathetic nervous system (SNS), is an aetiological factor in a number of diseases. 2 In a previous paper (Fitzgerald, Int. J. Cancer, 124, 2009, 257), I examined evidence that elevated NA is a factor in various types of cancer. Here I extend the argument to several other diseases, including diabetes mellitus, open-angle glaucoma, osteoarthritis and rheumatoid arthritis and asthma. 3 The principal hypothesis is that, largely as a result of genetics, elevated noradrenergic tone in the SNS predisposes a large number of individuals to a broad range of diseases. 4 For each of the above five diseases, I briefly examine the following four lines of evidence to assess the hypothesis: i) whether pharmacological studies in rodents that manipulate NA levels or receptors affect these diseases; ii) whether pharmacological manipulation of NA in humans affects these diseases; iii) whether bipolar disorder, excessive body weight, and hypertension, which may all three involve elevated NA, tend to be comorbid with these diseases and iv) whether psychological stressors tend to cause or exacerbate these conditions, since psychological stress is associated with increased release of NA. 5 The four lines of evidence tend to support the hypothesis.

The role of Epac proteins, novel cAMP mediators, in the regulation of immune, lung and neuronal function

Chronic degenerative inflammatory diseases, such as chronic obstructive pulmonary disease and Alzheimer's dementia, afflict millions of people around the world, causing death and debilitation. Despite the global impact of these diseases, there have been few innovative breakthroughs into their cause, treatment or cure. As with many debilitating disorders, chronic degenerative inflammatory diseases may be associated with defective or dysfunctional responses to second messengers, such as cyclic adenosinemonophosphate (cAMP). The identification of the cAMP-activated guanine nucleotide exchange factors for Ras-like GTPases, Epac1 (also known as cAMP-GEF-I) and Epac2 (also known as cAMP-GEF-II), profoundly altered the prevailing assumptions concerning cAMP signalling, which until then had been solely associated with protein kinase A (PKA). Studies of the molecular mechanisms of Epac-related signalling have demonstrated that these novel cAMP sensors regulate many physiological processes either alone and/or in concert with PKA. These include calcium handling, cardiac and smooth muscle contraction, learning and memory, cell proliferation and differentiation, apoptosis, and inflammation. The diverse signalling properties of cAMP might be explained by spatio-temporal compartmentalization, as well as A-kinase anchoring proteins, which seem to coordinate Epac signalling networks. Future research should focus on the Epac-regulated dynamics of cAMP, and, hopefully, the development of compounds that specifically interfere with the Epac signalling system in order to determine the precise significance of Epac proteins in chronic degenerative inflammatory disorders.

Asthma patients' self-reported behaviours toward inhaled corticosteroids

BACKGROUND

Patient adherence to recommended use of ICS is questionable in asthma, with irregular use or interruptions occurring frequently. Factors explaining discontinuation of controller therapy could orientate interventions. The characteristics of patients with interruptions of inhaled corticosteroids (ICSs), intentional or accidental, were investigated.

METHODS

Asthma patients regularly prescribed ICS by GPs (Cegedim network) were included. Patients' characteristics and behaviours toward ICS (accidental/intentional interruptions, less frequent use of ICS and change in dosing) were identified from self-report questionnaires, and linked to data prescription database. Interrelations between declared behaviours toward ICS were studied with a Multiple Component Analysis (MCA) and the correlates of ICS interruptions were identified.

RESULTS

During the past 3 months, 31.6% of 204 patients (mean age: 53.8 years, females: 59.3%) intentionally interrupted ICS when feeling better, 25.4% forgot ICS and 18.3% deliberately changed the doses. A quarter of patients considered constant use of respiratory medicines as unhealthy. MCA revealed that intentional, accidental interruptions and less frequent use of ICS were closely correlated. Risk of intentional interruption was increased when patients considered constant use of respiratory therapy to be unhealthy (OR=3.36, 95%CI=[1.47-7.66]). Conversely, risk was significantly lower when ICS was associated or combined with another controller (OR=0.24, 95%CI=[0.08-0.73]), compared to ICS in monotherapy. Less frequent interruptions were observed in patients older than 65 (OR=0.35, 95%CI=[0.13-0.89]).

CONCLUSIONS

Our study suggests that discontinuation of use of controllers is associated with other inadequate behaviours or beliefs about inhaled controllers. Efforts should be targeted at patients' perceptions and behaviours toward controller therapy.

Antiinflammatory effects of long-acting beta2-agonists in patients with asthma: a systematic review and metaanalysis

BACKGROUND

Long-acting beta(2)-agonists (LABAs) are recommended as add-on therapy to antiinflammatory treatment in patients with chronic persistent asthma. Results from individual studies evaluating the in vivo antiinflammatory effect of LABAs are conflicting. The purpose of this metaanalysis was to determine whether LABAs have an in vivo antiinflammatory effect compared to placebo and whether the addition of a LABA to therapy with inhaled corticosteroids (ICSs) has a synergistic or additive antiinflammatory effect.

METHODS

A systematic search was performed of online databases for randomized controlled trials evaluating the antiinflammatory effects of the following: (1) LABAs compared to placebo; and (2) a LABA plus ICS vs ICS alone in adults and children with asthma. Inflammatory outcome measures included cell counts and markers of cell activation in sputum, BAL fluid, bronchial biopsy specimens, serum, and exhaled nitric oxide (ENO). Data were independently extracted by two study investigators and analyzed to generate standardized mean differences using either a fixed or random-effects metaanalysis depending on the degree of heterogeneity.

RESULTS

Thirty-two studies (n = 1,105 participants) met the inclusion criteria. The mean number of participants and mean number of studies for each inflammatory outcome in the metaanalysis was 113.1 (SD, 46.2) and 3.5 (SD, 1.3), respectively. There was no effect of LABA therapy on sputum, BAL fluid, or mucosal inflammatory cells in adults or in children. LABA therapy decreased ENO levels and BAL fluid albumin levels in adults. In children, LABA therapy was associated with a small decrease in serum eosinophils and interleukin-4.

CONCLUSION

LABA therapy does not appear to have any clinically important antiinflammatory or proinflammatory effect. LABA therapy decreases BAL fluid albumin levels, suggesting a possible modulating effect on microvascular leakage.

Budesonide/Formoterol pressurized metered-dose inhaler

*The corticosteroid budesonide and the long-acting [beta]2-adrenoceptor agonist formoterol have been combined into a single pressurized metered-dose inhaler (pMDI) for use in patients aged > or =12 years with asthma. *In well designed 12-week clinical trials in patients with mild to moderate or moderate to severe persistent asthma, lung function improved to a significantly greater extent with twice-daily budesonide/formoterol pMDI 160 [micro]g/9 [micro]g or 320 [micro]g/9 [micro]g than with placebo or the same nominal dosage of either of the components alone. *Budesonide/formoterol pMDI was also associated with improvements from baseline in patient-reported asthma control, asthma symptom and asthma-related quality of life outcomes that were significantly greater than those with placebo and, for many endpoints, monotherapy with the individual components. *In a 52-week safety study, treatment with twice-daily budesonide/formoterol pMDI 320 [micro]g/9 [micro]g was associated with rapid and durable improvements in lung function and asthma control that were significantly greater than those with twice-daily budesonide pMDI 640 [micro]g monotherapy. *Budesonide/formoterol pMDI was well tolerated in clinical trials. Its overall adverse event profile is consistent with the known tolerability profiles of long-acting [beta]2-adrenoceptor agonist and inhaled corticosteroid therapy, and is similar to that shown with placebo.

Budesonide/formoterol: a review of its use as maintenance and reliever inhalation therapy in asthma

The use of combination budesonide/formoterol dry powder inhaler (Symbicort Turbuhaler) for both daily maintenance therapy and as-needed relief of breakthrough symptoms using a single inhaler is a new approach to asthma management that is indicated in patients with persistent asthma not adequately controlled by conventional regimens using reliever therapy with a short-acting beta(2)-adrenoceptor agonist alone. The administration of additional corticosteroid with each reliever inhalation in response to symptoms is expected to provide improved control of airway inflammation.Budesonide/formoterol maintenance and reliever therapy reduced the risk of severe asthma exacerbations compared with conventional regimens using a short-acting beta(2)-adrenoceptor agonist alone as reliever therapy in the majority of trials, while providing similar or better daily asthma control than higher fixed maintenance doses of budesonide or inhaled corticosteroid/long-acting beta(2)-adrenoceptor agonist combination therapy in patients with generally moderate to severe, uncontrolled, persistent asthma. The strategy offers the convenience of a single inhaler and simplifies treatment by providing immediate additional anti-inflammatory medication in response to asthma symptoms and immediate step-down when symptoms abate. The improved efficacy, with respect to exacerbation prevention, observed with budesonide/formoterol maintenance and reliever therapy in all double-blind comparative trials was achieved with a lower mean daily dose of inhaled corticosteroid or with fewer daily inhalations of reliever medication. Budesonide/formoterol maintenance and reliever therapy was well tolerated with an incidence of adverse events similar to that with conventional regimens. Therefore, it offers a new approach to therapy in patients with uncontrolled, persistent asthma; providing improved efficacy with a lower overall drug load.

Interactive effects of steroids and beta-agonists on accumulation of type 2 T cells

BACKGROUND

Airway inflammation associated with asthma has been reported to be either unaffected or slightly increased by inhaled beta-agonist monotherapy, and concerns regarding disease exacerbations with continuous long-acting beta-agonist monotherapy have prompted the recommendation of concomitant steroid treatment.

OBJECTIVES

Using peripheral blood lymphocytes from asthmatic subjects, we aimed to determine (1) whether short- or long-acting beta-agonists increase IL-13-producing (IL-13+ or IFN-gamma-producing (IFN-gamma+ T-cell numbers and (2) the ability of the corticosteroid budesonide to reverse these effects.

METHODS

Peripheral blood lymphocytes from asthmatic subjects were cultured 6 days ex vivo with IL-2 and various concentrations of albuterol, formoterol, and budesonide. Numbers of IL-13+ and IFN-gamma+ T cells were determined by means of flow cytometric analysis.

RESULTS

Both albuterol and formoterol increased IL-2-stimulated accumulation of IL-13+ T cells, and this increase was highest at concentrations approximating the dissociation constant of each beta-agonist for the beta(2)-adrenergic receptor. Budesonide at greater than 1 nmol/L reversed the augmenting effects of beta-agonists on IL-13+ T-cell accumulation, and budesonide at greater than 10 nmol/L inhibited increases in IL-13+ T cells stimulated by IL-2. Budesonide decreased, whereas beta-agonist did not affect, numbers of total and IFN-gamma+ T cells in IL-2-stimulated cultures.

CONCLUSION

beta-Agonists at physiologically and clinically relevant concentrations stimulate increased antigen-independent, cytokine-stimulated accumulation, specifically of type 2 T cells from asthmatic subjects. The corticosteroid budesonide potently reverses this effect.

Optimization of dosing schedule of daily inhalant dexamethasone to minimize phase shifting of clock gene expression rhythm in the lungs of the asthma mouse model

Glucocorticoid receptor agonists such as dexamethasone (DEXA) have been recommended for the treatment of asthma. An increased frequency of dosing with these drugs seems preferable for cases of severe or uncontrolled asthma. The purpose of this experiment was to find the appropriate dosing schedule (frequency and timing) for DEXA inhalation based on chronotherapeutic dosing to minimize phase shifts of clock function in the lungs of the ovalbumin-treated asthmatic mouse. The daily rhythm of clock gene expression was similar between control and ovalbumin-treated mice. Acute inhalation of DEXA significantly increased mPer1 gene expression in the lungs but not the liver of mice. Daily exposure of DEXA at zeitgeber time 0 (lights on) or at zeitgeber time 18 (6 h after lights off) for 6 d caused a phase advance or phase delay of bioluminescence rhythm in the lungs, respectively, similar to light-induced phase shifts in locomotor activity rhythm. Daily zeitgeber time 0 exposure to DEXA attenuated the expression level of the mClca3 gene, which is associated with mucus overproduction, and there was a phase-advancing peak time of the mClca3 rhythm. The present results denote the importance of selecting the most appropriate time of day for nebulizer administration of DEXA to minimize adverse effects such as the phase shifting of clock function in asthmatic lungs. This is the first report of a successful protocol that could obtain phase shifts of clock gene expression rhythm in isolated peripheral organs in vivo.

Combined inhaled steroids and bronchodilatators in obstructive airway disease after allogeneic stem cell transplantation

Bronchiolitis obliterans (BO) is a potentially life-threatening complication following allogeneic stem cell transplantation (SCT) and usually carries a poor prognosis. Immunosuppressive medications are the main treatment, but are rarely effective, especially when the disease is severe. Thus, both early detection and alternative therapeutic approaches of post SCT BO are needed. We report our experience with Budesonide/Formoterol, an inhaled steroid and long-acting bronchodilatator combination, in a group of patients with mild to moderately severe BO after SCT whose systemic immunosuppressive treatment had not been modified. Thirteen patients were treated. The diagnosis of BO was based on the presence of respiratory symptoms and air-trapping on expiratory lung high-resolution computed tomography in all patients, associated with irreversible airflow obstruction in seven cases. The median follow-up was 12.8 months (range: 5-29 months). All patients improved clinically, and both forced expiratory volume in 1 (FEV(1)) and mean expiratory flow values increased significantly during follow-up (534+/-268 ml in absolute values and 36+/-27% compared to pretreatment values for FEV(1); P<0.02). These encouraging results provide new insights in the therapeutic approach of BO after SCT and require confirmation in a larger group of patients with a longer follow-up.

Interactions between corticosteroids and beta2-agonists

In vitro studies have demonstrated numerous ways in which beta2-agonists and corticosteroids may interact. Together with evidence of improved control of airway diseases using a combination therapy of inhaled corticosteroids and long-acting beta-agonists compared with treatment with either drug alone, this suggests that there may be a beneficial synergy between these two classes of medication. However, a positive interaction has not been clearly demonstrated in vivo. There is little evidence that beta2-agonists enhance the anti-inflammatory actions of inhaled corticosteroids. Corticosteroids do not enhance the bronchodilator response to beta2- agonists, nor do they appear to prevent the development of tolerance during chronic beta2-agonist treatment. The evidence that high doses of corticosteroids can reverse tolerance to beta2-agonists is conflicting. Most of the clinical benefits from combinations using inhaled corticosteroids and long-acting beta-agonists to treat asthma could result from additive or complimentary effects of the drugs on different parts of the disease process. Nevertheless, there are several studies in which the combination of a long- or short-acting beta-agonist with an inhaled corticosteroid appears to have provided more than additive clinical benefits. The issue warrants further study. Combined inhaled corticosteroid/beta-agonist treatment will remain the basis of asthma management for the foreseeable future, and although the overall clinical benefit of the combination is no longer in doubt, there is more to learn about maximizing this benefit and minimizing adverse effects.

beta-Agonist enhances type 2 T-cell survival and accumulation

BACKGROUND

Neurohumoral modulation of immune system function is poorly understood. beta-Adrenergic receptor ligands (beta-agonists) subserve numerous physiologic processes but also function as pathogenic or therapeutic agents in numerous diseases with inflammatory components.

OBJECTIVES

We sought to establish the effects of beta-agonists and prostaglandin E(2) (PGE(2)) on antigen-dependent and antigen-independent accumulation of IL-13(+) (type 2) and IFN-gamma(+) (type 1) T cells. We also sought to clarify the mechanisms mediating the effects of these G protein-coupled receptor agonists.

METHODS

Effects of beta-agonists or PGE(2) on T-cell subtype accumulation were assessed in peripheral blood lymphocytes cultured with alphaCD3/CD28 or IL-2 by using flow cytometry. The role of cyclic AMP-dependent protein kinase (PKA) in mediating agonist effects was assessed by means of characterization of (1) phosphorylation of an intracellular PKA substrate and (2) T cells from patients with lupus possessing a natural defect in PKA activation.

RESULTS

beta-Agonists, in contrast to PGE(2), increased IL-2-induced accumulation of human type 2 T cells, an effect attributable to differential activation of PKA affecting regulation of cell proliferation and apoptosis. In T cells from patients with lupus exhibiting defective PKA activation, both beta-agonists and PGE(2) promoted an increase in type 2 T-cell accumulation.

CONCLUSION

G(s)-coupled receptors have the capacity to elicit prosurvival signaling in type 2 T cells, which, in most instances, is obscured by concomitant and antimitogenic PKA activation.

CLINICAL IMPLICATIONS

beta-Agonists and other G(s)-coupled receptor agonists have the potential to regulate T-cell development to affect disease pathogenesis or the efficacy of therapies, and variability of effect relates to the ability to stimulate PKA activity.

Treating asthma as an inflammatory disease

Asthma is a chronic inflammatory disease involving many different cell types and cellular elements. Evidence suggests that, in the long term, this inflammation leads to remodeling of the airways, airflow obstruction, and the bronchial hyperreactivity symptoms of asthma, and is present even in patients with intermittent disease. Patients with allergic asthma and those with seasonal allergic rhinitis are believed to have minimal persistent inflammation, and the two diseases often occur together. Early intervention with inhaled corticosteroids (ICS) is believed to modify the disease process and may limit long-term remodeling. ICS remain the cornerstone and "gold standard" of treatment for asthma.

Targeting G protein-coupled receptor signaling in asthma

The complex disease asthma, an obstructive lung disease in which excessive airway smooth muscle (ASM) contraction as well as increased ASM mass reduces airway lumen size and limits airflow, can be viewed as a consequence of aberrant airway G protein-coupled receptor (GPCR) function. The central role of GPCRs in determining airway resistance is underscored by the fact that almost every drug used in the treatment of asthma directly or indirectly targets either GPCR-ligand interaction, GPCR signaling, or processes that produce GPCR agonists. Although many airway cells contribute to the regulation of airway resistance and architecture, ASM properties and functions have the greatest impact on airway homeostasis. The theme of this review is that GPCR-mediated regulation of ASM tone and ASM growth is a major determinant of the acute and chronic features of asthma, and multiple strategies targeting GPCR signaling may be employed to prevent or manage these features.

Mucus and MUC in asthma

PURPOSE OF REVIEW

Asthma is characterized by chronic airway inflammation and a mucus hypersecretory phenotype comprising excess mucus secretion, goblet cell hyperplasia and submucosal gland hypertrophy. This augmented mucus secretion has been relatively undervalued in asthma compared with airway inflammation. However, mucus plugging contributes to airflow limitation and airway hyperresponsiveness, and to morbidity and mortality in asthma. We review recent contributions to this field and therapeutic avenues to control mucus hypersecretion.

RECENT FINDINGS

A distinct mucus hypersecretory phenotype may present in asthma. Overexpression of MUC5AC, MUC5B and MUC2 have been described in asthma secretions, but identification of defined biochemical abnormalities and polymorphisms of mucin genes linked to asthma remains elusive. Activation of epidermal growth factor receptor (EGFR) activation appears central in transducing many different stimuli, including oxidative stress, proteases and cytokines. In contrast, nitrosative stress has barely been investigated. The existence of crosstalk between EGFR and other receptor systems may provide new clues regarding the activity of acetylcholine, adenosine and other agonists of G-protein-coupled receptors and other receptor families on mucin secretion. Modern techniques for noninvasive detection of mucus pathology will advance clinical research in this field.

SUMMARY

Airway mucus hypersecretion as a part of airway remodelling represents a problem in asthma, and studies of pathophysiology and therapeutic approaches are therefore warranted. Identification of targets such as the EGFR cascade, which are crucial in excessive and abnormal mucus secretion, may lead to the rational design of new antihypersecretory drugs that may enhance future asthma treatment.

Influence of epithelium and isoprenaline incubation on responsiveness of guinea-pig trachea to methacholine

There are reports regarding harmful effect of long-term use of beta2-agonist drugs on asthma severity and airway responsiveness. In the present study, the responses of guinea pig trachea with intact and denuded epithelium (groups 1 and 2, n = 10) to methacholine as EC50 were measured in tissues nonincubated or incubated with 10 mumol/l isoprenaline during the resting period. The same protocol was performed in groups 3 and 4 (n = 5 for each group) with an additional 30 min rest time after isoprenaline incubation. The response of trachea with denuded epithelium (groups 2 and 4) to methacholine was significantly higher than that with intact epithelium both in incubated and nonincubated conditions (groups 1 and 3, p < 0.05 to p < 0.001). Incubation with isoprenaline caused a significant reduction in the tracheal response to methacholine in both the denuded groups (p < 0.005 and p < 0.001) and intact epithelium groups (p < 0.005 for both cases). The reduction in tracheal responsiveness to methacholine due to incubation in epithelium denuded trachea (groups 2 and 4) was nonsignificantly greater than that of intact epithelium tissues. There was no difference between groups 3 and 4 with those of groups 1 and 2 in both incubated and non incubated conditions. The maximum contractility response to methacholine was not different between tracheal chains with denuded and intact epithelium and did not change due to incubation with isoprenaline. The results of this study indicate reduction of tracheal response to methacholine due to incubation of tissues with isoprenaline, which was relatively more pronounced in epithelium denuded trachea.

Improving asthma control in patients suboptimally controlled on inhaled steroids and long-acting beta2-agonists: addition of montelukast in an open-label pilot study

BACKGROUND

Airway inflammation and symptoms often persist in asthma patients despite treatment with inhaled corticosteroids (ICS) and long-acting beta2-agonists (LABA). It is hypothesized that the leukotriene receptor antagonist montelukast, treating a pathway of inflammation distinct from that of ICS, might confer additional benefit.

OBJECTIVE

To evaluate the efficacy of montelukast in improving asthma control in patients symptomatic on a fixed-association (FA) medium dose of ICS and LABA.

METHODS

A 2-month, open-label, real-life observational study was undertaken by 131 Belgian pulmonologists. Patients (> or = 15 years old) suffering from persistent asthma (pre-bronchodilator FEV1 > or = 60% of predicted value) and insufficiently controlled on a FA therapy of fluticasone/salmeterol or budesonide/formoterol were given montelukast 10 mg daily as add-on therapy. Asthma control was assessed by the standardized Juniper asthma control questionnaire (ACQ) at baseline and after a 2-month treatment with montelukast. Global evaluation of therapy was made both by the patients and physicians.

RESULTS

A total of 313 patients were eligible for analysis. Forty-nine per cent received inhaled fluticasone/salmeterol and the rest budesonide/formoterol. Mean ACQ score decreased significantly on montelukast (13.9 +/- 5.1 at baseline versus 7.4 +/- 4.7 on montelukast, p < 0.001), with a significant improvement in all individual symptom scores (p < 0.001) and in pre-bronchodilator FEV1 score (from 2.2 +/- 1.5 to 1.6 +/- 1.4; p < 0.001). Parallel to these results, 78.6% of the patients reported a global improvement of their asthma. The same proportion of improvement was observed in the global evaluation made by the physicians (kappa = 0.66).

CONCLUSION

This pilot study suggests that addition of montelukast in patients symptomatic on a FA of ICS and LABA may result in significant improvements in asthma control. A randomised, placebo-controlled clinical trial seems warranted.