Combination therapy of long-acting beta2-adrenoceptor agonists and corticosteroids for asthma

Using sigma-ligands as part of a multi-receptor approach to target diseases of the brain

INTRODUCTION

The sigma receptors are found abundantly in the central nervous system and are targets for the treatment of various diseases, including Alzheimer's (AD), Parkinson's (PD), Huntington's disease (HD), depression, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS). However, for many of these diseases, other receptors and targets have been the focus of the most, such as acetylcholine esterase inhibitors in Alzheimer's and dopamine replacement in Parkinson's. The currently available drugs for these diseases have limited success resulting in the requirement of an alternative approach to their treatment.

AREAS COVERED

In this review, we discuss the potential role of the sigma receptors and their ligands as part of a multi receptor approach in the treatment of the diseases mentioned above. The literature reviewed was obtained through searches in databases, including PubMed, Web of Science, Google Scholar, and Scopus.

EXPERT OPINION

Given sigma receptor agonists provide neuroprotection along with other benefits such as potentiating the effects of other receptors, further development of multi-receptor targeting ligands, and or the development of multi-drug combinations to target multiple receptors may prove beneficial in the future treatment of degenerative diseases of the CNS, especially when coupled with better diagnostic techniques.

Asthma phenotypes and T-bet protein expression in cells treated with Fluticasone Furoate/Vilanterol

Asthma is a complex disease with diverse clinical manifestations ranging from mild to severe. Despite existing guidelines for asthma recognition and treatment, still a proportion of patients stay uncontrolled. Combinational therapy which comprises inhaled corticosteroids (ICS) and a long acting B2 adrenreceptor agonist (LABA) has been suggested to control asthma. In this study T-bet expression was attested in CD4 T cells treated with Fluticasone Furoate (FF), Vilanterol (V) and FF/V combination in severe asthmatic patients compared to patients with moderate asthma and healthy controls using Immunocytochemistry (ICC). First, CD4 T cells were isolated from PBMCs of 12 patients and controls using CD4 T cell isolation kit. Subsequently, isolated CD4 T cells were cultured with FF, V and FF/V for 1 h. To accomplish ICC, cells were incubated with anti-T-bet antibody, and then stained with HRP-bound secondary antibody. T-bet expression was evaluated using light microscopy. Statistical analyses were performed using R 3.5.2 software and visualized by ggplot2 3.1.0 package. Significant increasing in T-bet expression was seen in CD4 T cells from patients with moderate asthma treated with FF and FF/V. Suggesting conclusion would be distinct mechanisms responsible for severe asthma and moderate asthma in the patients and the needs for novel therapies. Further molecular studies in different asthma phenotypes would be instructive for asthma treatment.

Controversies in Pediatric Asthma

Pediatric asthma, the most common chronic disease of childhood, remains a significant burden to the health care system. Although there are guidelines for the management of pediatric asthma, there remain several controversies about how best to manage asthma in the primary care setting, and how to prevent asthma exacerbations and subsequent emergency department visits and hospitalizations. In this article, we address four of these controversies: use of written asthma treatment plans, the role of long-acting beta-agonists, spirometry and peak flow measurements in disease management, and engagement of school nurses in the health care team. We provide suggestions and guidance related to these topics for the pediatric primary care provider. [Pediatr Ann. 2019;48(3):e128-e134.].

Intratracheal administration of adipose derived mesenchymal stem cells alleviates chronic asthma in a mouse model

BACKGROUND

Adipose-derived mesenchymal stem cell (ASCs) exerts immunomodulatory roles in asthma. However, the underlying mechanism remains unclear. The present study aimed to explore the effects and mechanisms of ASCs on chronic asthma using an ovalbumin (OVA)-sensitized asthmatic mouse model.

METHODS

Murine ASCs (mASCs) were isolated from male Balb/c mice and identified by the expression of surface markers using flow cytometry. The OVA-sensitized asthmatic mouse model was established and then animals were treated with the mASCs through intratracheal delivery. The therapy effects were assessed by measuring airway responsiveness, performing immuohistochemical analysis, and examining bronchoalveolar lavage fluid (BALF). Additionally, the expression of inflammatory cytokines and lgE was detected by CHIP and ELISA, respectively. The mRNA levels of serum indices were detected using qRT-PCR.

RESULTS

The mASCs grew by adherence with fibroblast-like morphology, and showed the positive expression of CD90, CD44, and CD29 as well as the negative expression of CD45 and CD34, indicating that the mASCs were successfully isolated. Administering mASCs to asthmatic model animals through intratracheal delivery reduced airway responsiveness, the number of lymphocytes (P < 0.01) and the expression of lgE (P < 0.01), IL-1β (P < 0.05), IL-4 (P < 0.001), and IL-17F (P < 0.001), as well as increased the serum levels of IL-10 and Foxp3, and the percentage of CD4 + CD25 + Foxp3+ Tregs in the spleen, and reduced the expression of IL-17 (P < 0.05) and RORγ.

CONCLUSIONS

Intratracheal administration of mASCs alleviated airway inflammation, improved airway remodeling, and relieved airway hyperresponsiveness in an OVA-sensitized asthma model, which might be associated with the restoration of Th1/Th2 cell balance by mASCs.

Stimulus-selective regulation of human mast cell gene expression, degranulation and leukotriene production by fluticasone and salmeterol

Despite the fact that glucocorticoids and long acting beta agonists are effective treatments for asthma, their effects on human mast cells (MC) appear to be modest. Although MC are one of the major effector cells in the underlying inflammatory reactions associated with asthma, their regulation by these drugs is not yet fully understood and, in some cases, controversial. Using a human immortalized MC line (LAD2), we studied the effects of fluticasone propionate (FP) and salmeterol (SM), on the release of early and late phase mediators. LAD2 cells were pretreated with FP (100 nM), SM (1 µM), alone and in combination, at various incubation times and subsequently stimulated with agonists substance P, C3a and IgE/anti-IgE. Degranulation was measured by the release of β-hexosaminidase. Cytokine and chemokine expression were measured using quantitative PCR, ELISA and cytometric bead array (CBA) assays. The combination of FP and SM synergistically inhibited degranulation of MC stimulated with substance P (33% inhibition compared to control, n = 3, P<.05). Degranulation was inhibited by FP alone, but not SM, when MC were stimulated with C3a (48% inhibition, n = 3, P<.05). As previously reported, FP and SM did not inhibit degranulation when MC were stimulated with IgE/anti-IgE. FP and SM in combination inhibited substance P-induced release of tumor necrosis factor (TNF), CCL2, and CXCL8 (98%, 99% and 92% inhibition, respectively, n = 4, P<.05). Fluticasone and salmeterol synergistically inhibited mediator production by human MC stimulated with the neuropeptide substance P. This synergistic effect on mast cell signaling may be relevant to the therapeutic benefit of combination therapy in asthma.

Th17 immunity in children with allergic asthma and rhinitis: a pharmacological approach

Th17 cells and IL-17A play a role in the development and progression of allergic diseases. We analyzed the IL-17A levels in sputum supernatants (Ss), nasal wash (NW) and plasma (P) from Healthy Controls (HC) and children with Asthma/Rhinitis. We tested the expression of IL-17A, RORγ(t) and FOXP3 in peripheral blood T-lymphocytes from intermittent and mild-moderate asthma. The effect of Budesonide and Formoterol was tested “in vitro” on IL-17A, RORγ(t) and FOXP3 expression in cultured T-lymphocytes from mild-moderate asthma/persistent rhinitis patients, and on nasal and bronchial epithelial cells stimulated with NW and Ss from mild-moderate asthma/persistent rhinitis. Further, the effect of 12 weeks of treatment with Budesonide and Formoterol was tested “in vivo” in T-lymphocytes from mild-moderate asthma/persistent rhinitis patients. IL-17A was increased in Ss, NW and P from children with mild-moderate asthma compared with intermittent and HC. In cultured T-lymphocytes IL-17A and RORγ(t) expression were higher in mild-moderate asthma/persistent rhinitis than in mild-moderate asthma/intermittent rhinitis, while FOXP3 was reduced. Budesonide with Formoterol reduced IL-17A and RORγ(t), while increased FOXP3 in cultured T-lymphocytes from mild-moderate asthma/persistent rhinitis, and reduced the IL-8 release mediated by IL-17A present in NW and Ss from mild-moderate asthma/persistent rhinitis in nasal and bronchial epithelial cells. Finally, Budesonide with Formoterol reduced IL-17A levels in P and Ss, CD4⁺IL-17A⁺T-cells, in naïve children with mild-moderate asthma/persistent rhinitis after 12 weeks of treatment. Th17 mediated immunity may be involved in the airway disease of children with allergic asthma and allergic rhinitis. Budesonide with Formoterol might be a useful tool for its therapeutic control.

Effect of nebulized beclomethasone on airway inflammation and clinical status of children with allergic asthma and rhinitis: a randomized, double-blind, placebo-controlled study

We aimed to evaluate the therapeutic effect of nebulized beclomethasone dipropionate (nBDP) on both allergic asthma and rhinitis. In a randomized, double-blind, placebo-controlled study, 40 children (mean age 10.7 ± 2.1 years) with allergic asthma and rhinitis received either nBDP (daily dose of 800 µg, administered twice daily) or placebo for 4 weeks (with a face mask), after a 2-week run-in period of clinical assessment. Nasal and oral fractional exhaled nitric oxide (FeNO) measurements together with pulmonary function tests, nasal and oral exhaled breath condensate (EBC) collection for pH and interleukin-5 (IL-5) measurements as well as nasal and bronchial symptom scores were obtained at baseline and after 4-week treatment. A significant improvement in oral FeNO, oral and nasal EBC IL-5 and nasal EBC pH was observed in the nBDP group when comparing the values with baseline, together with an improvement in symptom score of the visual analogue scale, nasal obstruction, sneezing, rhinorrhea, breathing difficulty, cough, wheezing and sleep disturbance (nBDP end treatment vs. baseline, Wilcoxon signed-rank test). nBDP was more effective than placebo (ANCOVA test) in improving [difference Δ = response after treatment at the last visit (active or placebo) - value at baseline] nasal pH, oral IL-5, oral FeNO, forced expiratory volume in 1 s, forced expiratory volume in 1 s/forced vital capacity, peek expiratory flow, visual analogue scale, breathing difficulty, cough, wheezing and sleep disturbance scores. No differences were observed between the nBDP and the placebo group for symptom score of rhinitis. nBDP is a useful treatment for airway inflammation and clinical status in children with concomitant allergic asthma and rhinitis.

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.

Should treatments for asthma be aimed at the airway smooth muscle?

The airway smooth muscle (ASM) cell is an important part of the airway wall of asthma patients because of its increased contractile properties, which appear to be enhanced in this condition and which contribute to airflow obstruction and bronchial hyper-responsiveness. ASM cells are also abnormal in asthma with increased expression of certain chemokines, with increased proliferation rate, numbers and size. beta-adrenergic agonists and corticosteroids are the two most important treatments for asthma; other drugs used are leukotriene receptor antagonists and theophylline. Combination therapy of beta-adrenergic agonists and corticosteroids has become the treatment of choice for moderate-to-severe asthma. beta-adrenergic agonists cause relaxation of ASM cells, leading to a decrease in airflow obstruction of asthma and acute relief of symptoms. Corticosteroids also have direct effects on ASM cells. It is postulated that the effect of anti-inflammatory agents on ASM cells is the most important determinant of the therapeutic effects of these agents. Targeting the ASM cell in asthma could be the focus of therapies for asthma. Specific delivery of active agents to ASM cells may also be part of this strategy.

Protease inhibitors in respiratory disease: focus on asthma and chronic obstructive pulmonary disease

Respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD), are a major health burden on society and current treatment modalities for these diseases have not significantly changed over the past 40 years. The only major pharmacological advancement for the treatment of these diseases has been to increase the duration of action of bronchodilators (asthma: salmeterol; COPD: tiotropium bromide) and glucocorticosteroids (asthma: fluticasone propionate) and, increasingly, to formulate these agents in the same delivery device. Despite our increasing understanding of the cell and molecular biology of these diseases, the development of novel treatments remains beyond the reach of the scientific community. Proteases are a family of proteins with diverse biological activity, which are found in abundance within the airways of asthma and COPD, and have been implicated in the pathogenesis of these diseases. The targeting of proteases, including mast cell tryptase, neutrophil elastase and matrix metalloprotease with low-molecular-weight inhibitors, has highlighted the potential role of these enzymes in mediating certain aspects of the disease process in preclinical studies. Several challenges remain regarding the development of protease inhibitors, including the synthesis of highly potent and specific inhibitors, and target validation in man.

Current trends in the treatment of asthma: focus on the simultaneous administration of salmeterol/fluticasone

Asthma is a chronic disease of the airways that affects over 20 million people in the United States. It is a complex disease that involves airway infiltration by different types of cells and cell mediators causing chronic inflammation of the airway as well as hyper-responsiveness and edema. Management of asthma symptoms often requires combination therapy with multiple medications. Long-acting beta-2 agonists and inhaled corticosteroids have become key medications in the prevention of asthma exacerbations. The bronchodilatory effects of the beta-2 agonists coupled with the anti-inflammatory action of the corticosteroids combat the multi-factorial causes of asthma. The combination inhaler containing salmeterol and fluticasone is one such product that has been proven safe and effective for asthma therapy.

Salmeterol/fluticasone propionate: a review of its use in asthma

Salmeterol/fluticasone propionate (Seretide/Advair Diskus [dry powder inhaler] or Seretide/Advair inhalation aerosol [metered-dose inhaler]) is a fixed-dose combination inhalation agent containing a long-acting beta2-adrenoceptor agonist (LABA) plus a corticosteroid. In patients with symptomatic asthma, twice-daily salmeterol/fluticasone propionate maintenance therapy improves lung function and asthma symptoms to a greater extent than monotherapy with inhaled corticosteroids (ICS), such as fluticasone propionate, oral montelukast with or without fluticasone propionate, or sustained-release theophylline plus fluticasone propionate. The greater efficacy achieved with salmeterol/fluticasone propionate versus fluticasone propionate alone was sustained for 1 year in a well designed trial. Salmeterol/fluticasone propionate is also associated with a corticosteroid-sparing effect. Results of studies comparing fixed dosages of salmeterol/fluticasone propionate with formoterol/budesonide in adults and adolescents are equivocal. Twice-daily salmeterol/fluticasone propionate is associated with clinically meaningful improvements from baseline in health-related quality of life (HR-QOL), and improvements were greater than those reported with fluticasone propionate alone. Salmeterol/fluticasone propionate is generally well tolerated in adults, adolescents and children aged 4-11 years, and the fixed-combination inhaler ensures the appropriate use of a LABA in combination with an ICS. In cost-utility analyses in patients with uncontrolled asthma, salmeterol/fluticasone propionate compares favourably with fluticasone propionate alone or oral montelukast. Thus, salmeterol/fluticasone propionate provides an effective, well tolerated and cost-effective option for maintenance treatment in patients with asthma.

Inhaled corticosteroids as combination therapy with beta-adrenergic agonists in airways disease: present and future

Inhaled corticosteroid (ICS) therapy in combination with long-acting beta-adrenergic agonists represents the most important treatment for chronic airways diseases such as asthma and chronic obstructive pulmonary disease (COPD). ICS therapy forms the basis for treatment of asthma of all severities, improving asthma control, lung function and preventing exacerbations of disease. Use of ICS has also been established in the treatment of COPD, particularly symptomatic patients, who experience useful gains in quality of life, likely from an improvement in symptoms such as breathlessness and in reduction in exacerbations, and an attenuation of the yearly rate of deterioration in lung function. The addition of long-acting beta-agonist (LABA) therapy with ICS increases the efficacy of ICS effects in moderate-to-severe asthma. Thus, a 800 mug daily dose of the ICS budesonide reduced severe exacerbation rates by 49% compared to a low dose of 200 mug daily, and addition of the LABA formoterol to budesonide (800 mug) led to a 63% reduction. In COPD, the effects of ICS are less prominent but there are beneficial effects on the decline in FEV(1) and the rate of exacerbations. A reduction in the rate of decline in FEV(1) of 16 ml/year with a 25% reduction in exacerbation rate has been reported with the salmeterol and fluticasone combination. A non-significant 17.5% reduction in all-cause mortality rate with ICS and LABA is reported. Chronic inflammation is a feature of both asthma and COPD, although there are site and characteristic differences. ICS targets this inflammation although this effect of ICS is less effective in patients with severe asthma and with COPD; however, addition of LABA may potentiate the anti-inflammatory effects of ICS. An important consideration is the presence of corticosteroid insensitivity in these patients. Currently available ICS have variably potent binding activities to specific glucocorticoid receptors, leading to inhibition of gene expression by either binding to DNA and inducing anti-inflammatory genes or by repressing the induction of pro-inflammatory mediators. Local side effects of ICS include oral candidiasis, hoarseness and dysphonia, while systemic side effects, such as easy bruising and reduction in growth velocity or bone mineral densitometry, are usually restricted to doses above maximally recommended doses. Use of LABA alone in patients with asthma increases the risk of asthma-related events including deaths, but this is less observed with the combination of ICS and LABA. Therefore, use of LABA alone is not recommended for asthma therapy. Future progress in ICS development will be characterised by the introduction of ICS with greater efficacy with a limited side-effect profile, and by longer-acting ICS that can be used in combination with once-daily LABAs. Other agents that could improve the efficacy of corticosteroids or reverse corticosteroid insensitivity may be added to ICS. ICS in combination with LABAs will continue to remain the main focus of treatment of airways diseases.

Glucocorticoids and mitogen- and stress-activated protein kinase 1 inhibitors: possible partners in the combat against inflammation

In the combat against inflammation, glucocorticoids (GCs) are a widespread therapeutic. These ligands of the glucocorticoid receptor (GR) inhibit the transactivation of various transcription factors, including nuclear factor-kappaB (NF-kappaB), and alter the composition of the pro-inflammatory enhanceosome, culminating in the repression of pro-inflammatory gene expression. However, pharmacological usage of GCs in long-term treatment is burdened with a detrimental side-effect profile. Recently, we discovered that GCs can lower NF-kappaB transactivation and pro-inflammatory gene expression by abolishing the recruitment of mitogen- and stress-activated protein kinase 1 (MSK1) (EC 2.7.11.1) to pro-inflammatory gene promoters and displacing a significant fraction of MSK1 to the cytoplasm. In our current investigation in L929sA fibroblasts, upon combining GCs and MSK1 inhibitors, we discovered a dose-dependent additive repression of pro-inflammatory gene expression, most likely due to diverse and multilayered repression mechanisms employed by GCs and MSK1 inhibitors. Therefore, the combined application of GCs and MSK1 inhibitors enabled a similar level of repression of pro-inflammatory gene expression, using actually a lower concentration of GCs and MSK1 inhibitors combined than would be necessary when using these inhibitors separately. Although H89 can inhibit both MSK1 and PKA, TNF does not activate PKA (EC 2.7.11.11) and as such PKA inhibition does not mediate H89-instigated repression of TNF-stimulated gene expression. Furthermore, the additional repressive effects of liganded GR and inhibition of MSK1, are not mediated via GR transactivation mechanisms. In conclusion, these results could entail a new therapeutic strategy using lower drug concentrations, potentially leading to a more beneficial side-effect profile.

New targets for drug development in asthma

Asthma is a chronic inflammatory disease that affects about 300 million people worldwide, a total that is expected to rise to about 400 million over the next 15-20 years. Most asthmatic individuals respond well to the currently available treatments of inhaled corticosteroids and beta-adrenergic agonists; however, 5-10% have severe disease that responds poorly. Improved knowledge of asthma mechanisms has led to the recognition of different asthma phenotypes that might reflect distinct types of inflammation, explaining the effectiveness of anti-leucotrienes and the anti-IgE monoclonal antibody omalizumab in some patients. However, more knowledge of the inflammatory mechanisms within the airways is required. Improvements in available therapies-such as the development of fast-onset, once-a-day combination drugs with better safety profiles-will occur. Other drugs, such as inhaled p38 MAPK inhibitors and anti-oxidants, that target specific pathways or mediators could prove useful as monotherapies, but could also, in combination with corticosteroids, reduce the corticosteroid insensitivity often seen in severe asthma. Biological agents directed against the interleukin-13 pathway and new immunoregulatory agents that modulate functions of T-regulatory and T-helper-17 cells are likely to be successful. Patient-specific treatments will depend on the development of discriminatory handprints of distinct asthma subtypes and are probably over the horizon. Although a cure is unlikely to be developed in the near future, a greater understanding of disease mechanisms could bring such a situation nearer to reality.

Multifunctional neuroprotective drugs targeting monoamine oxidase inhibition, iron chelation, adenosine receptors, and cholinergic and glutamatergic action for neurodegenerative diseases

A new paradigm is emerging in the targeting of multiple disease aetiologies that collectively lead to neurodegenerative disorders such as Parkinson's disease, Alzheimer's disease, post-stroke neurodegeneration and others. This paradigm challenges the widely held assumption that 'silver bullet' agents are superior to 'dirty drugs' when it comes to drug therapy. Accumulating evidence in the literature suggests that many neurodegenerative diseases have multiple mechanisms in their aetiologies, thus suggesting that a drug with at least two mechanisms of action targeted at multiple aetiologies of the same disease may offer more therapeutic benefit in certain disorders compared with a drug that only targets one disease aetiology. This review offers a synopsis of therapeutic strategies and novel investigative drugs developed in the authors' own and other laboratories that modulate multiple disease targets associated with neurodegenerative diseases.

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.

Beclometasone dipropionate/formoterol: in an HFA-propelled pressurised metered-dose inhaler

A hydrofluoroalkane (HFA)-propelled pressurised metered-dose inhaler (pMDI) has been developed (using Modulite technology) for a new fixed combination of beclometasone dipropionate/formoterol fumarate (BDP/formoterol) 100 microg/6 microg. Each actuation of the BDP/formoterol HFA pMDI 100 microg/6 microg delivers 86.4 microg of BDP and 5 microg of formoterol. BDP/formoterol HFA pMDI was associated with significantly higher morning peak expiratory flow (PEF) values than BDP administered alone via a chlorofluorocarbon (CFC) pMDI (including when BDP was administered at a higher dosage) in well designed trials in adults with mild to moderate or moderate to severe asthma. In terms of morning PEF values, BDP/formoterol HFA pMDI was noninferior to BDP plus formoterol administered via separate inhalers in well designed trials in adults with moderate to severe asthma. BDP/formoterol HFA pMDI was noninferior to fixed-combination budesonide/formoterol (the daily dosage of BDP was half that of budesonide) in terms of lung function, asthma symptoms and use of rescue medications in adults with moderate to severe asthma. BDP/formoterol HFA pMDI was also noninferior to, and had a faster onset of bronchodilation than, fixed-combination fluticasone propionate/salmeterol. BDP/formoterol 200 microg/12 microg per day or 400 microg/24 microg per day administered by the HFA pMDI was generally well tolerated. Moreover, a single high dose of BDP/formoterol (1000 microg/60 microg) was generally well tolerated in patients with asthma.

Multifunctional drugs with different CNS targets for neuropsychiatric disorders

The multiple disease etiologies that lead to neuropsychiatric disorders, such as Parkinson's and Alzheimer's disease, amyotrophic lateral sclerosis, Huntington disease, schizophrenia, depressive illness and stroke, offer significant challenges to drug discovery efforts aimed at preventing or even reversing the progression of these disorders. Transcriptomic tools and proteomic profiling have clearly indicated that such diseases are multifactorial in origin. Further, they are thought to be initiated by a cascade of molecular events that involve several neurotransmitter systems. In response to this complexity, a new paradigm has recently emerged that challenges the widely held assumption that 'silver bullet' agents are superior to 'dirty drugs' in therapeutic approaches aimed at the prevention or treatment of neuropsychiatric diseases. A similar pattern of drug development has occurred in strategies for the treatment of cancer, AIDS and cardiovascular diseases. In this review, we offer an overview of therapeutic strategies and novel investigative drugs discovered or developed in our own and other laboratories, that address multiple CNS etiological targets associated with an array of neuropsychiatric disorders.

Understanding the pathophysiology of severe asthma to generate new therapeutic opportunities

Although asthma is defined in terms of reversibility of airflow obstruction, as the disease becomes more severe and chronic, it adopts different characteristics, including a degree of fixed airflow obstruction and corticosteroid refractoriness. Underlying these phenotypes is evidence of airway wall remodeling, which should be distinguished from the increase in smooth muscle linked to airways hyperresponsiveness. Aberrant epithelial-mesenchymal communication leads to a chronic wound scenario, which is characterized by activation of the epithelial-mesenchymal trophic unit, epithelial damage, the laying down of new matrix, and greater involvement of neutrophils in the inflammatory response. In allergic asthmatic patients who remain symptomatic despite high-dose corticosteroid therapy, blockade of IgE with omalizumab confers appreciable clinical benefit. Chronic severe asthma is also accompanied by a marked increase in TNF-alpha production that might contribute to corticosteroid refractoriness. Based on this, TNF blockade with the soluble fusion protein entanercept produces improvement in asthma symptoms, lung function, and quality of life paralleled by a marked reduction in airways hyperresponsiveness. Identification of novel susceptibility genes, such as a disintegrin and metalloprotease 33 (ADAM33), will provide further targets against which to direct novel therapies for asthma, especially at the more severe end of the disease spectrum.

Update on glucocorticoid action and resistance

Extensive development of inhaled and oral glucocorticoids has resulted in highly potent molecules that have been optimized to target activity to the lung and minimize systemic exposure. These have proved highly effective for most asthmatic subjects, but despite these developments, there are a number of subjects with asthma who fail to respond to even high doses of inhaled or even oral glucocorticoids. Advances in delineating the fundamental mechanisms of glucocorticoid pharmacology, especially the concepts of transactivation and transrepression and cofactor recruitment, have resulted in better understanding of the molecular mechanisms whereby glucocorticoids suppress inflammation. The existence of multiple mechanisms underlying glucocorticoid insensitivity raises the possibility that this might indeed reflect different diseases with a common phenotype, and studies examining the efficacy of potential new agents should be targeted toward subgroups of patients with severe corticosteroid-resistant asthma who clearly require effective new drugs and other approaches to improved asthma control.

Inhaled salmeterol/fluticasone propionate: a review of its use in asthma

Salmeterol/fluticasone propionate, administered twice daily via a multidose dry powder inhaler (Seretide/Advair Diskus), Seretide Accuhaler or metered-dose hydrofluoroalkane (chlorofluorocarbon-free) inhaler (Seretide Evohaler), is a combination of the long-acting beta(2)-adrenoceptor agonist (beta(2)-agonist) [LABA] salmeterol and the corticosteroid fluticasone propionate. Maintenance therapy with combined salmeterol/fluticasone propionate is at least as effective in improving lung function and symptoms and is as well tolerated in patients with asthma as concurrent salmeterol plus fluticasone propionate. In patients previously receiving as-required short-acting beta(2)-agonists (SABAs) or inhaled corticosteroids, salmeterol/fluticasone propionate was significantly more effective in providing asthma control than fluticasone propionate and in improving lung function and asthma symptoms than inhaled corticosteroids (at equivalent or higher dosages), salmeterol or montelukast (as monotherapy or in combination with fluticasone propionate). Salmeterol/fluticasone propionate was more effective in improving asthma symptoms than adjusted-dose budesonide/formoterol in patients with uncontrolled asthma despite treatment with inhaled corticosteroids with or without a LABA in a well designed 1-year study. In pharmacoeconomic analyses, salmeterol/fluticasone propionate compared favourably with inhaled corticosteroids and mono- or combination therapy with oral montelukast. Salmeterol/fluticasone propionate is, therefore, an effective, well tolerated and cost-effective option for the maintenance treatment of patients with asthma.

Beta-adrenoceptor responses of the airways: for better or worse?

Beta2-adrenoceptor agonists are the first-line treatment of asthma and chronic obstructive pulmonary disease (COPD), in which a short-acting beta2-adrenoceptor agonist is used as required for relief of bronchoconstriction. A long-acting beta2-adrenoceptor agonist may be added to an inhaled corticosteroid as step 3 in the management of chronic asthma. Long-acting beta2-adrenoceptor agonists may also be added in treatment of COPD. This review examines the beneficial and detrimental effects of beta2-adrenoceptor agonists. The beneficial effects of beta2-adrenoceptor agonists are mainly derived from their bronchodilator activity which relieves the bronchiolar narrowing and improves air flow. The potential anti-inflammatory actions of stabilizing mast cell degranulation and release of inflammatory and bronchoconstrictor mediators, is considered. Other potential beneficial responses include improvements in mucociliary clearance and inhibition of extravasation of plasma proteins that is involved in oedema formation in asthma. The side effects of beta2-adrenoceptor agonists are primarily related to beta2-adrenoceptor-mediated responses at sites outside the airways. Of major concern has been the development of tolerance and this is discussed in relation to incidence of increased morbidity and mortality to asthma over the past three decades. A clinical aspect of beta2-adrenoceptor pharmacology in recent years has been the recognition of genetic polymorphism of the receptor and how this affects responses to and tolerance to beta2-adrenoceptor agonists. A controversial feature of beta2-adrenoceptor agonists is their stereoisomerism and whether the inactive (S)-isomer of salbutamol had detrimental actions in the commercially used racemate. The consensus is that despite these adverse properties, beta2-adrenoceptor agonist remains the most useful pharmacological agents in the management of asthma and COPD.

Characterization of 16 human G protein-coupled receptors expressed in baculovirus-infected insect cells

Understanding the three-dimensional structure of G protein-coupled receptors (GPCRs) has been limited by the technical challenges associated with expression, purification, and crystallization of membrane proteins, and their low abundance in native tissue. In the first large-scale comparative study of GPCR protein production using recombinant baculovirus, we report the characterization of 16 human receptors. The GPCRs were produced in three insect cell lines and functional protein levels monitored over 72 h using radioligand binding assays. Different GPCRs exhibited widely different expression levels, ranging from less than 1 pmol receptor/mg protein to more than 250 pmol/mg. No single set of conditions was suitable for all GPCRs, and large differences were seen for the expression of individual GPCRs in different cell lines. Closely related GPCRs did not share similar expression profiles; however, high expression (greater than 20 pmol/mg) was achieved for over half the GPCRs in our study. Overall, the levels of protein production compared favourably to other published systems.

Interleukin-10-secreting "regulatory" T cells induced by glucocorticoids and beta2-agonists

Greater clinical benefit in controlling the symptoms of asthma is frequently observed through combining moderate doses of inhaled glucocorticoids together with long-acting beta(2)-agonists, as compared with increasing glucocorticoid dosage alone. To address in vitro whether glucocorticoids plus beta(2)-agonists, compared with glucocorticoids alone, have greater inhibitory activity on CD4+ T cell responses to allergen, peripheral blood CD4+ T cell responses to allergen were compared in the presence or absence of the glucocorticoid fluticasone proprionate and the short- and long-acting beta(2)-agonists salbutamol and salmeterol, respectively. Fluticasone proprionate inhibited interleukin (IL)-5 and IL-13 and enhanced IL-10 synthesis in allergen-stimulated cultures in a concentration-dependent manner. Salmeterol, but not salbutamol, inhibited IL-5 and IL-13 and enhanced IL-10 synthesis in these cultures. When used in combination the two drugs demonstrated an additive effect on this pattern of cytokine production. Allergen-specific T cell lines induced in the presence of salmeterol and fluticasone proprionate inhibited IL-5 and IL-13 production by allergen-specific Th2 cell lines in an IL-10-dependent manner. Thus fluticasone proprionate and salmeterol increased IL-10 and reduced Th2 cytokine synthesis additively in allergen stimulated human CD4+ T cells.