Interactions between corticosteroids and beta agonists

Standard medical therapy with vs. without nebulised magnesium for children with asthma decompensation

Pediatric asthma is a common condition, and its exacerbations can be associated with significant morbidity and mortality. The role of nebulised magnesium as adjunct therapy for children with asthma exacerbations is still unclear. To compare clinical and functional outcomes for children with asthma exacerbation taking either nebulised magnesium sulfate added to standard medical therapy (SMT) versus SMT alone. PubMed, Embase, and Cochrane Library were systematically searched for randomised clinical trials (RCT) comparing the use of SMT with vs. without nebulised magnesium. The outcomes were respiratory rate, heart rate, % predicted peak expiratory flow rate (PEFR), % predicted forced expiratory volume (FEV1), peripheral O2 saturation, asthma severity scores, and need for intravenous (IV) bronchodilator use. Twelve RCTs and 2484 children were included. Mean age was 5.6 (range 2-17) years old, mean baseline % predicted FEV1 was 69.6%, and 28.66% patients were male. Children treated with magnesium had a significantly higher % predicted PEFR (mean difference [MD] 5.33%; 95% confidence interval [CI] 4.75 to 5.90%; p < 0.01). Respiratory rate was significantly lower in the magnesium group (MD -0.70 respirations per minute; 95% CI -1.24 to -0.15; p < 0.01). Need for IV bronchodilators, % predicted FEV1, heart rate, asthma severity scores, and O2 saturation were not significantly different between groups.

CONCLUSION

In children with asthma exacerbation, treatment with nebulised magnesium and SMT was associated with a statistically significant, but small improvement in predicted PEFR and respiratory rate, as compared with SMT alone.

WHAT IS KNOWN

• Magnesium sulfate has bronchodilating properties and aids in the treatment of asthma exacerbation when administered intravenously. • There is no significant evidence of benefit of nebulised magnesium as an adjunct therapy to the standard medical treatment for children with asthma exacerbations.

WHAT IS NEW

• Our study suggests nebulised magnesium sulfate may have a statistically significant, but small benefit in respiratory rate and peak expiratory flow rate. The addition of nebulised magnesium does not seem to increase adverse events.

The Wiser Strategy of Using Beta-Agonists in Asthma: Mechanisms and Rationales

Concerns regarding the safety of beta-2 agonists have led to revisions of the major asthma guidelines to better address these issues. Although these updates allow for a combination of previous and current strategies, they may confuse clinical practitioners. Beta-2 agonists are vital for alleviating asthma symptoms by relaxing smooth muscles; however, they also pose significant risks by inducing pro-inflammatory mediators both in vitro and in vivo. In addition to the risks of overuse and symptom masking, the use of beta-agonists alone at therapeutic doses can worsen airway inflammation and enhance virus-induced inflammation during asthma exacerbation. Inhaled corticosteroids (ICS) can effectively prevent these adverse effects. With new insights into the mechanisms of these adverse events, reserving short-acting beta-agonists for acute symptom relief during exacerbations and only for those who are already on ICS or oral steroids represents a careful approach to using beta-agonists with least adverse effects in patients with asthma. However, a major drawback of this approach is the potential non-compliance with ICS, leading to beta-agonist use without the necessary counteraction by ICS. An optimal strategy, both during and outside exacerbations, would integrate beta-agonists into an anti-inflammatory regimen that includes ICS, ideally combined with the same inhaler to ensure their concurrent use where finances allow. This would maintain the beneficial effects of beta-agonists, such as bronchodilation, while preventing the adverse effects from the induction of inflammatory mediators. This method is aligned with diverse clinical settings, maximizes the safe use of beta-agonists, and supports a comprehensive guideline-compliant management strategy.

Synephrine and Its Derivative Compound A: Common and Specific Biological Effects

This review is focused on synephrine, the principal phytochemical found in bitter orange and other medicinal plants and widely used as a dietary supplement for weight loss/body fat reduction. We examine different aspects of synephrine biology, delving into its established and potential molecular targets, as well as its mechanisms of action. We present an overview of the origin, chemical composition, receptors, and pharmacological properties of synephrine, including its anti-inflammatory and anti-cancer activity in various in vitro and animal models. Additionally, we conduct a comparative analysis of the molecular targets and effects of synephrine with those of its metabolite, selective glucocorticoid receptor agonist (SEGRA) Compound A (CpdA), which shares a similar chemical structure with synephrine. SEGRAs, including CpdA, have been extensively studied as glucocorticoid receptor activators that have a better benefit/risk profile than glucocorticoids due to their reduced adverse effects. We discuss the potential of synephrine usage as a template for the synthesis of new generation of non-steroidal SEGRAs. The review also provides insights into the safe pharmacological profile of synephrine.

Differential Roles of Interleukin-6 in Severe Acute Respiratory Syndrome-Coronavirus-2 Infection and Cardiometabolic Diseases

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection can lead to a cytokine storm, unleashed in part by pyroptosis of virus-infected macrophages and monocytes. Interleukin-6 (IL-6) has emerged as a key participant in this ominous complication of COVID-19. IL-6 antagonists have improved outcomes in patients with COVID-19 in some, but not all, studies. IL-6 signaling involves at least 3 distinct pathways, including classic-signaling, trans-signaling, and trans-presentation depending on the localization of IL-6 receptor and its binding partner glycoprotein gp130. IL-6 has become a therapeutic target in COVID-19, cardiovascular diseases, and other inflammatory conditions. However, the efficacy of inhibition of IL-6 signaling in metabolic diseases, such as obesity and diabetes, may depend in part on cell type-dependent actions of IL-6 in controlling lipid metabolism, glucose uptake, and insulin sensitivity owing to complexities that remain to be elucidated. The present review sought to summarize and discuss the current understanding of how and whether targeting IL-6 signaling ameliorates outcomes following SARS-CoV-2 infection and associated clinical complications, focusing predominantly on metabolic and cardiovascular diseases.

The Changing Asthma Management Landscape and Need for Appropriate SABA Prescription

Short-acting β2 agonists (SABAs) have been a mainstay of asthma treatment since the 1950s, and have been mainly recommended as-needed for symptom relief alongside daily inhaled corticosteroid (ICS)-based maintenance treatment for the past 30 years. However, patient adherence to regular ICS-based anti-inflammatory maintenance therapy is frequently poor, leading to SABA overuse for symptom relief and associated poor outcomes. At present, there is a lack of consensus between treatment guidelines on how SABA should be used, and as-needed ICS-formoterol is suggested by some as an alternative reliever therapy. Here, we examine the pharmacology and current use of inhaled SABAs, identify that regular dosing of ICS can encourage appropriate SABA use, and appraise the evidence used to support the changing reliever treatment recommendations. We conclude that SABA continues to play an important role in the asthma management landscape, and give our views on how it should be used in patients with mild-moderate asthma, to complement regular ICS-based maintenance treatment.

Recent Updates on Corticosteroid-Induced Neuropsychiatric Disorders and Theranostic Advancements through Gene Editing Tools

The vast use of corticosteroids (CCSs) globally has led to an increase in CCS-induced neuropsychiatric disorders (NPDs), a very common manifestation in patients after CCS consumption. These neuropsychiatric disorders range from depression, insomnia, and bipolar disorders to panic attacks, overt psychosis, and many other cognitive changes in such subjects. Though their therapeutic importance in treating and improving many clinical symptoms overrides the complications that arise after their consumption, still, there has been an alarming rise in NPD cases in recent years, and they are seen as the greatest public health challenge globally; therefore, these potential side effects cannot be ignored. It has also been observed that many of the neuronal functional activities are regulated and controlled by genomic variants with epigenetic factors (DNA methylation, non-coding RNA, and histone modeling, etc.), and any alterations in these regulatory mechanisms affect normal cerebral development and functioning. This study explores a general overview of emerging concerns of CCS-induced NPDs, the effective molecular biology approaches that can revitalize NPD therapy in an extremely specialized, reliable, and effective manner, and the possible gene-editing-based therapeutic strategies to either prevent or cure NPDs in the future.

Corticosteroid administration and glycemic outcomes during treatment of acute exacerbation of chronic obstructive pulmonary disease

Background

While international guidelines recommend low doses of systemic corticosteroids for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) clinical practice patterns show significant heterogeneity. Increasing doses of corticosteroids have inconsistently been associated with a greater risk of hyperglycemia.

Methods

Patients admitted to inpatient services for AECOPD were retrospectively enrolled. Hospitalization corticosteroid doses, daily blood glucose levels, and other markers of corticosteroid excess were collected. Correlative and regression analyses were conducted to assess the relationship between corticosteroid dose and average hospitalization blood glucose.

Results

Daily corticosteroid dose significantly predicted a higher blood glucose (rs=0.179, p=0.0095; p<0.0028 respectively) and cumulative corticosteroid dose predicted a longer hospital length of stay in bivariate and multivariate analyses (rs=0.679, p<0.0001; p<0.0001 respectively). Patients that experienced hypernatremia, hypokalemia, acute hyperglycemia, and acute hypertension received larger corticosteroid doses than patients that did not experience these complicating events.

Conclusions

We identified that increasing amounts of corticosteroids administered to inpatients experiencing AECOPD experienced higher average hospitalization blood glucose values, protracted hospitalizations, and other untoward effects.

Budesonide/glycopyrronium/formoterol fumarate triple therapy prevents pulmonary hypertension in a COPD mouse model via NFκB inactivation

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a health problem that results in death, commonly due to the development of pulmonary hypertension (PH). Here, by utilizing a mouse model of intratracheal elastase-induced emphysema that presents three different phases of COPD, we sought to observe whether budesonide/glycopyrronium/formoterol fumarate (BGF) triple therapy could prevent COPD-PH in addition to ameliorating COPD progression.

METHODS

We utilized intratracheal elastase-induced emphysema mouse model and performed experiments in three phases illustrating COPD progression: inflammatory (1 day post-elastase), emphysema (3 weeks post-elastase) and PH (4 weeks post-elastase), while treatments of BGF and controls (vehicle, one-drug, and two-drug combinations) were started in prior to elastase instillation (inflammatory phase), at day 7 (emphysema), or at day 14 (PH phase). Phenotype analyses were performed in each phase. In vitro, A549 cells or isolated mouse lung endothelial cells (MLEC) were treated with TNFα with/without BGF treatment to analyze NFκB signaling and cytokine expression changes.

RESULTS

We observed significant reductions in the proinflammatory phenotype observed in the lungs and bronchoalveolar lavage fluid (BALF) 1 day after elastase administration in mice treated with BGF compared with that in mice administered elastase alone (BALF neutrophil percentage, p = 0.0011 for PBS/Vehicle vs. PBS/Elastase, p = 0.0161 for PBS/Elastase vs. BGF). In contrast, only BGF treatment significantly ameliorated the elastase-induced emphysematous lung structure and desaturation after three weeks of elastase instillation (mean linear intercept, p = 0.0156 for PBS/Vehicle vs. PBS/Elastase, p = 0.0274 for PBS/Elastase vs. BGF). Furthermore, BGF treatment prevented COPD-PH development, as shown by improvements in the hemodynamic and histological phenotypes four weeks after elastase treatment (right ventricular systolic pressure, p = 0.0062 for PBS/Vehicle vs. PBS/Elastase, p = 0.027 for PBS/Elastase vs. BGF). Molecularly, BGF acts by inhibiting NFκB-p65 phosphorylation and subsequently decreasing the mRNA expression of proinflammatory cytokines in both alveolar epithelial and pulmonary endothelial cells.

CONCLUSION

Our results collectively showed that BGF treatment could prevent PH in addition to ameliorating COPD progression via the inhibition of inflammatory NFκB signaling.

Analysis of medication patterns for pediatric asthma patients in emergency department: Does the sequence placement of glucocorticoids administration matter?

Objectives: Timely glucocorticoid administration is associated with decreased admission rate and is thus a common quality metric for ED asthma care; less is known about the impact of the timing of glucocorticoids in the context of the sequence of asthma medications administered. Therefore, we investigated the distribution of asthma medication sequences in one ED and analyzed the effect of the sequence placement of glucocorticoids administration on treatment outcomes.Methods: A retrospective study using five-year electronic health record data obtained from an academic urban children's hospital ED was conducted. We clustered the sequences of medication administration using an exact string-matching algorithm to identify the most frequently used asthma medication sequences. Then, we used the identified patterns to perform statistical tests to examine the effect of the sequence placement of glucocorticoids administration on the outcomes length-of-stay and ED disposition.Results: A total of 4,844 encounters were included in our study. The ten most common treatment sequences accounted for 43% of all encounters. Stratified analyses confirmed that treatment sequences pattern was correlated with patient severity, but ED crowding does not impact treatment sequences. In multivariable models, glucocorticoids administration earlier in the treatment sequence was associated with shorter length of stay and lower hospital admission rates.Conclusions: By analyzing medication sequence patterns for the ED encounter of pediatric asthma, we found that the earlier sequence placement of glucocorticoids administration is associated with improved outcomes. Our findings can help inform quality improvement and clinical guideline development related to ED asthma care for children.

The Phosphodiesterase Inhibitor Ensifentrine Reduces Production of Proinflammatory Mediators in Well Differentiated Bronchial Epithelial Cells by Inhibiting PDE4

Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel that impair airway salt and fluid secretion. Excessive release of proinflammatory cytokines and chemokines by CF bronchial epithelium during airway infection leads to chronic inflammation and a slow decline in lung function; thus, there is much interest in finding safe and effective treatments that reduce inflammation in CF. We showed previously that the cyclic nucleotide phosphodiesterase (PDE) inhibitor ensifentrine (RPL554; Verona Pharma) stimulates the channel function of CFTR mutants with abnormal gating and also those with defective trafficking that are partially rescued using a clinically approved corrector drug. PDE inhibitors also have known anti-inflammatory effects; therefore, we examined whether ensifentrine alters the production of proinflammatory cytokines in CF bronchial epithelial cells. Ensifentrine reduced the production of monocyte chemoattractant protein-1 and granulocyte monocyte colony-stimulating factor (GM-CSF) during challenge with interleukin-1β Comparing the effect of ensifentrine with milrinone and roflumilast, selective PDE3 and PDE4 inhibitors, respectively, demonstrated that the anti-inflammatory effect of ensifentrine was mainly due to inhibition of PDE4. Beneficial modulation of GM-CSF was further enhanced when ensifentrine was combined with low concentrations of the β 2-adrenergic agonist isoproterenol or the corticosteroid dexamethasone. The results indicate that ensifentrine may have beneficial anti-inflammatory effects in CF airways particularly when used in combination with β 2-adrenergic agonists or corticosteroids. SIGNIFICANCE STATEMENT: Airway inflammation that is disproportionate to the burden of chronic airway infection causes much of the pathology in the cystic fibrosis (CF) lung. We show here that ensifentrine beneficially modulates the release of proinflammatory factors in well differentiated CF bronchial epithelial cells that is further enhanced when combined with β2-adrenergic agonists or low-concentration corticosteroids. The results encourage further clinical testing of ensifentrine, alone and in combination with β2-adrenergic agonists or low-concentration corticosteroids, as a novel anti-inflammatory therapy for CF.

Current Bronchodilator Responsiveness Criteria Underestimate Asthma in Older Adults

BACKGROUND

Asthma is common in older adults and is confirmed by demonstration of variable expiratory air-flow limitations, typically evaluated by spirometric assessment of bronchodilator responsiveness. However, many patients with clinically suspected asthma and documented air-flow obstruction do not exhibit a post-bronchodilator response that meets or exceeds current established guidelines. We investigated if extending the time from bronchodilator administration to assessment of bronchodilator response increases the yield of spirometry for the diagnosis of asthma in older adults.

METHODS

This was a cross-sectional study. The subjects were non-smokers, ≥ 60 y old, and with suspected asthma. Subjects were characterized as (1) those with a positive bronchodilator response on the 30-min post-bronchodilator spirometry, (2) those with a positive bronchodilator response on the 60-min post-bronchodilator spirometry, and (3) those without a positive bronchodilator response but with a positive methacholine challenge test. Factors associated with a late response to bronchodilator were evaluated by using bivariate analysis and by multivariate analysis by using a logistic regression model.

RESULTS

This study enrolled 165 subjects. Of these, 81 (49.1%) had a positive bronchodilator response on 30-min post-bronchodilator spirometry; 25 (15.2%) had a positive bronchodilator response on the 1-h post-bronchodilator spirometry; and 59 (35.8%) had no positive bronchodilator response but had a positive methacholine challenge test. On multivariable regression analysis, those with a higher baseline percentage of predicted FEV₁, higher scores on a standard asthma control test, and wheezing and/or cough after exercise were more likely to either have a late bronchodilator response or no bronchodilator response.

CONCLUSIONS

Our study showed that a late positive response to bronchodilator use was more common than previously presumed in older subjects with suspected asthma. Pulmonary function testing laboratories should consider routinely reassessing spirometry at 1 h after bronchodilator use if the earlier assessment did not reveal a significant response.

Effect of Bronchodilator and Steroid Use on Heart Disease and Stroke Risks in a Bronchiectasis-Chronic Obstructive Pulmonary Disease Overlap Cohort: A Propensity Score Matching Study

Background: To determine the effects of bronchodilator, steroid, and anti-arrhythmia drug use on the risk of heart disease/stroke (HDS) in patients with bronchiectasis–chronic obstructive pulmonary disease overlap syndrome (BCOS).

Methods: We retrospectively enrolled patients with BCOS (BCOS cohort, n = 1,493) and patients without bronchiectasis and chronic obstructive pulmonary disease (COPD) (non-BCOS cohort, n = 5,972). The cumulative incidence of HDS was analyzed through Cox proportional regression. We calculated adjusted hazard ratios (aHRs) and their 95% confidence intervals (CIs) for HDS after adjustments for sex, age, comorbidities, long-acting β2-agonist or long-acting muscarinic antagonist (LABAs/LAMAs) use, short-acting β2-agonist or short-acting muscarinic antagonist (SABAs/SAMAs) use, oral steroid (OSs) or inhaled corticosteroid steroid (ICSs) use, and anti-arrhythmia drugs use.

Results: The aHR (95% CI) for HDS was 1.08 (0.28–4.06) for patients using LAMAs compared with those not using drugs. Regarding drug use days, the aHRs (95% CIs) were 32.2 (1.79–773.0), 1.85 (1.01–3.39), and 31.1 (3.25–297.80) for those with recent SABAs use, past ICSs use, and past anti-arrythmia drugs use, respectively. Regarding cumulative drug dose, the aHRs (95% CIs) were 2.12 (1.46–3.10), 3.48 (1.13–10.6), 3.19 (2.04–4.99), 28.1 (1.42–555.7), 2.09 (1.32–3.29), 2.28 (1.53–3.40), and 1.93 (1.36–2.74) for those with a low dose of SABAs, medium dose of SABAs, low dose of SAMAs, low dose of ICSs, medium dose of ICSs, low dose of OSs, and medium dose of OSs, respectively.

Conclusions: Compared with patients without bronchiectasis and COPD, BCOS patients with recent SABAs, past ICSs, and past anti-arrhythmia drugs use; a low or medium SABAs ICSs, and OSs dose; and a low SAMAs dose had a higher risk of HDS. LAMAs were not associated with HDS.

Improving timeliness for acute asthma care for paediatric ED patients using a nurse driven intervention: an interrupted time series analysis

Asthma is the most common chronic paediatric disease treated in the emergency department (ED). Rapid corticosteroid administration is associated with improved outcomes, but our busy ED setting has made it challenging to achieve this goal. Our primary aim was to decrease the time to corticosteroid administration in a large, academic paediatric ED. We conducted an interrupted time series analysis for moderate to severe asthma exacerbations of one to 18 year old patients. A multidisciplinary team designed the intervention of a bedside nurse initiated administration of oral dexamethasone, to replace the prior system of a physician initiated order for oral prednisone. Our baseline and intervention periods were 12 month intervals. Our primary process measure was the time to corticosteroid administration. Other process measures included ED length of stay, admission rate, and rate of emesis. The balance measures included rate of return visits to the ED or clinic within five days, as well as the proportion of discharged patients who were admitted within five days. No special cause variation occurred in the baseline period. The mean time to corticosteroid administration decreased significantly, from 98 minutes in the baseline period to 59 minutes in the intervention period (p < 0.01), and showed special cause variation improvement within two months after the intervention using statistical process control methodology. We sustained the improvement and demonstrated a stable process. The intervention period had a significantly lower admission rate (p<0.01) and emesis rate (p<0.01), with no unforeseen harm to patients found with any of our balance measures. In summary, the introduction of a nurse initiated, standardized protocol for corticosteroid therapy for asthma exacerbations in a paediatric ED was associated with decreased time to corticosteroid administration, admission rates, and post-corticosteroid emesis.

Effect of glucocorticoids on the activity, expression and proximal promoter of type II deiodinase in rat brown adipocytes

Triiodothyronine (T3) is important for thermogenesis in brown adipose tissue (BAT). Type II deiodinase (DIO2) produces T3 required for intracellular needs in BAT. Brown adipocytes in culture require T3 for the adrenergic stimulation of DIO2. Glucocorticoids induce adipocyte differentiation (lipogenesis). We investigated the regulation of DIO2 activity, Dio2 mRNA and Dio2 promoter activity by glucocorticoids in primary cultures of rat brown adipocytes using dexamethasone (DEX) and hydrocortisone (HC). DEX and HC regulated the adrenergic stimulation of DIO2 activity in a dose- and time-dependent manner, inhibiting DIO2 activity at short treatment times and large doses (1-10 μM) and stimulating DIO2 at low HC doses (1-100 nM) and longer times (DEX). Insulin depletion reduced DIO2 activity but the response to glucocorticoids remained unchanged. DEX and HC inhibited basal DIO2 activity. DEX had no effect on DIO2 half-life, whereas HC stabilized DIO2 activity. DEX and HC inhibited the adrenergic stimulation of Dio2 mRNA expression (100-10000 nM, 14-96 h), but stabilized Dio2 mRNA, particularly DEX. DEX increased basal Dio2 mRNA levels, possibly through stabilization of Dio2 mRNA. An 807 bp construct of the murine Dio2 proximal promoter showed maximal reporter activity, with the cAMP response element (CRE) essential for transcriptional activity. DEX caused inhibition in most constructs containing the CRE element whereas HC stimulated reporter activity in the 807 bp construct. Glucocorticoids inhibited the adrenergic stimulation of Dio2 at the transcriptional level in brown adipocytes, although DIO2 activity increased with HC, possibly due to stabilization of Dio2 activity and mRNA. The CRE and cEBP elements of the Dio2 promoter seem involved in the regulation by glucocorticoids.

Emerging role of long-acting anticholinergics in children with asthma

PURPOSE OF REVIEW

Although the use of inhaled anticholinergics in obstructive airway disease has been established for several years, the clinical experience using these medications in treating patients with asthma is limited. Only few studies so far have included pediatric patients with asthma, but these studies demonstrate relevant therapeutic effects. This review will explore the pharmacological effects of inhaled anticholinergics, provide an overview about current adult and pediatric asthma studies using tiotropium, and describe future research needs.

RECENT FINDINGS

In a phase II study with tiotropium as add-on to maintenance treatment to inhaled corticosteroids (ICSs) in moderate persistent adolescent with asthma, significant improvement of peak and trough forced expiratory volume in 1 s (FEV1) with a good safety profile could be demonstrated. A pediatric phase II study in symptomatic patients with asthma aged 6-11with comparable study design also demonstrated significant improvement of peak FEV1 with no serious adverse events. However, both studies could not document a significant clinical improvement analyzed by standardized scores.

SUMMARY

Tiotropium might become an add-on treatment option in symptomatic pediatric and adolescent patients with asthma despite adequate therapy with ICS and long-acting β2-agonist (LABA) or as an alternative to LABA in patients with safety concerns related to LABA. For a better assessment of the clinical effect, long-term studies are needed.

Protective Effects of Clenbuterol against Dexamethasone-Induced Masseter Muscle Atrophy and Myosin Heavy Chain Transition

Background

Glucocorticoid has a direct catabolic effect on skeletal muscle, leading to muscle atrophy, but no effective pharmacotherapy is available. We reported that clenbuterol (CB) induced masseter muscle hypertrophy and slow-to-fast myosin heavy chain (MHC) isoform transition through direct muscle β2-adrenergic receptor stimulation. Thus, we hypothesized that CB would antagonize glucocorticoid (dexamethasone; DEX)-induced muscle atrophy and fast-to-slow MHC isoform transition.

Methodology

We examined the effect of CB on DEX-induced masseter muscle atrophy by measuring masseter muscle weight, fiber diameter, cross-sectional area, and myosin heavy chain (MHC) composition. To elucidate the mechanisms involved, we used immunoblotting to study the effects of CB on muscle hypertrophic signaling (insulin growth factor 1 (IGF1) expression, Akt/mammalian target of rapamycin (mTOR) pathway, and calcineurin pathway) and atrophic signaling (Akt/Forkhead box-O (FOXO) pathway and myostatin expression) in masseter muscle of rats treated with DEX and/or CB.

Results and Conclusion

Masseter muscle weight in the DEX-treated group was significantly lower than that in the Control group, as expected, but co-treatment with CB suppressed the DEX-induced masseter muscle atrophy, concomitantly with inhibition of fast-to-slow MHC isoforms transition. Activation of the Akt/mTOR pathway in masseter muscle of the DEX-treated group was significantly inhibited compared to that of the Control group, and CB suppressed this inhibition. DEX also suppressed expression of IGF1 (positive regulator of muscle growth), and CB attenuated this inhibition. Myostatin protein expression was unchanged. CB had no effect on activation of the Akt/FOXO pathway. These results indicate that CB antagonizes DEX-induced muscle atrophy and fast-to-slow MHC isoform transition via modulation of Akt/mTOR activity and IGF1 expression. CB might be a useful pharmacological agent for treatment of glucocorticoid-induced muscle atrophy.

Postoperative serum cortisol concentration and adrenal insufficiency in neonates undergoing open-heart surgery

BACKGROUND

We sought to determine whether immediate postoperative serum cortisol concentration predicts adrenal insufficiency in neonates after cardiac surgery with cardiopulmonary bypass. We hypothesized that cortisol <10 µg/dL would be associated with increased catecholamine requirements and fluid resuscitation and would predict hemodynamic responsiveness to exogenous steroids.

METHODS

Retrospective study of 41 neonates was carried out for the levels of cortisol in the immediate postoperative period; of whom, 15 received steroids due to high levels of inotropic support. Laboratory and clinical outcomes were collected.

RESULTS

Median cortisol was 12 µg/dL (interquartile range: 5.2-27.4). Levels of cortisol <10 µg/dL was not associated with any clinical variable indicative of increased illness severity. Peak lactate (9.1 vs 11.8 mmol/L, P = .04) and maximum arteriovenous saturation difference ([Sao 2 - Svo 2] 28% vs 32%, P = .05) were both lower among patients with levels of cortisol <10 µg/dL. Six (40%) patients had a significant hemodynamic improvement within 24 hours after receiving steroids (responders), although there was no statistical difference between levels of cortisol in responders versus nonresponders. Level of cortisol was positively correlated with maximum lactate (P < .001), maximum Sao 2 - Svo 2 (P < .001), maximum inotrope score (P = .014), initial 24-hour fluid intake (P = .012), and time to negative fluid balance (P = .008) and was negatively correlated with initial 24-hour urine output (P < .001).

CONCLUSIONS

Low cortisol obtained in the immediate postoperative period is not associated with worse postoperative outcomes or predictive of steroid responsiveness. In contrast, elevated levels of cortisol are positively correlated with severity of illness. The use of an absolute cortisol threshold to identify adrenal insufficiency and/or guide steroid therapy in neonates after cardiac surgery is unjustified.

A pilot study of polymorphism of adrenergic Beta-2 receptor and mild asthma: a clinical and pharmacogenetic study

Glycine allele at codon 16 has previously been associated with the increase in asthma severity, bronchial hyperresponsiveness and also the increase in inhaled corticosteroid dependence. This study was designed to evaluate the genetic alleles in mild asthma. Thirty-four patients with diagnosis of mild asthma (FEV1 ≥ 80%, positive methacholine test) and body mass index (BMI ≤ 30 Kg/m(2)) were included in the study. They could only use short acting beta-2 agonists for asthma control. Smoking, infection, occupational sensitizers' exposure, gastroesophageal reflux, diabetes mellitus and heart failure were also considered as exclusion criteria. All patients were genotyped at 16(th) and 27(th) codons. Among all, 20 (58.8%) Arg/Gly, 14 (41.2%) Arg/Arg and no Gly/Gly genotype were detected at codon 16. Genotyping at codon 27 revealed 2 (5.9%) Glu/Glu, 13 (38.2%) Glu/Gln and 18 Gln/Gln (52.9%). Based on the obtained results, Arg/Gly mutation had a higher rate among the studied subjects compared to Arg/Arg polymorphism. This is a pilot study which shows a probable usefulness of genotyping for predicting of asthma severity.

Impact of glucocorticoids on insulin resistance in the critically ill

Glucocorticoids (GCs) have been shown to reduce insulin sensitivity in healthy individuals. Widely used in critical care to treat a variety of inflammatory and allergic disorders, they may inadvertently exacerbate stress-hyperglycaemia. This research uses model-based methods to quantify the reduction in insulin sensitivity from GCs in critically ill patients, and thus their impact on glycaemic control. A model-based measure of insulin sensitivity (S(I)) was used to quantify changes between two matched cohorts of 40 intensive care unit (ICU) patients. Patients in one cohort received GC treatment, while patients in the control cohort did not. All patients were admitted to the Christchurch hospital ICU between 2005 and 2007 and spent at least 24h on the SPRINT glycaemic control protocol. A 31% reduction in whole-cohort median insulin sensitivity was seen between the control cohort and patients receiving glucocorticoids with a median dose equivalent to 200mg/d of hydrocortisone per patient. Comparing percentile patients as a surrogate for matched patients, reductions in median insulin sensitivity of 20%, 25%, and 21% were observed for the 25th-, 50th- and 75th-percentile patients, respectively. These cohort and percentile patient reductions are less than or equivalent to the 30-62% reductions reported in healthy subjects especially when considering the fact that the GC doses in this study are 1.3-4.0 times larger than those in studies of healthy subjects. This reduced suppression of insulin sensitivity in critically ill patients could be a result of saturation due to already increased levels of catecholamines and cortisol common in critically illness. Virtual trial simulation showed that reductions in insulin sensitivity of 20-30% associated with glucocorticoid treatment in the ICU have limited impact on glycaemic control levels within the context of the SPRINT protocol.

Bronchodilator responsiveness and onset of effect with budesonide/formoterol pMDI in COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) patients are thought to have limited bronchodilator response, determined by changes in forced expiratory volume in 1s (FEV(1)). In this study, we assessed bronchodilator response in patients with COPD using not only FEV(1) but also changes in lung volume expressed as forced vital capacity (FVC) and inspiratory capacity (IC). We also evaluated the speed of onset of bronchodilation.

METHODS

Data were from 2 randomized, double-blind, placebo-controlled studies (6-months [NCT00206154]; 12-months [NCT00206167]) in patients with moderate to very severe COPD.

TREATMENTS

twice daily budesonide/formoterol pressurized metered-dose inhaler (pMDI) 320/9μg, budesonide/formoterol pMDI 160/9μg, formoterol dry powder inhaler (DPI) 9μg, placebo.

RESULTS

The percentage of patients with FEV(1) improvement (≥12% and ≥200mL; American Thoracic Society [ATS] criterion) was 34-39% post-albuterol (screening). On day of randomization (DOR), a larger proportion receiving formoterol-containing treatment exhibited reversibility within 60min: FEV(1) (57-59%). Similar results were seen for IC (50-61%) and FVC (57-67%) using the same improvement criteria. The time to ≥15% FEV(1) improvement on DOR was 5.0, 4.8, and 7.3min for budesonide/formoterol 320/9, budesonide/formoterol 160/9, and formoterol, respectively. Time to ≥15% FEV(1) improvement was better maintained with budesonide/formoterol than formoterol at treatment end (6 and 12 months).

CONCLUSIONS

Most patients with moderate to very severe COPD exhibit ATS-defined bronchodilator reversibility based on flow and lung volume measures after budesonide/formoterol pMDI or formoterol treatment. Budesonide/formoterol pMDI also has a rapid (within 5min) onset of bronchodilation that is maintained over time compared with formoterol alone.

Regulation of tissue β-adrenergic, glucocorticoid and androgen receptors induced by repeated exposure to growth promoters in male veal calves

Biochemical modifications induced by a combination of anabolic compounds in target organs of male veal calves have been evaluated. Six male Friesian crossbred calves were treated with of 17beta-estradiol, dexamethasone sodium phosphate and clenbuterol or served as controls. beta-Adrenoceptors (beta-ARs) were measured in myocardium, lung, spleen, cerebral cortex, hippocampus, thalamus, hypothalamus, and hypophysis, glucocorticoid receptors (GRs) in the spleen and androgen receptors (AnRs) in the testis, by binding assay. A significant decrease in beta-ARs was observed in all tissue samples from treated animals. In the spleen the two GR subtypes found, low (LA) and high (HA) affinity GRs, were down-regulated by the treatment. A significant (P<0.05) decrease of testis weight and a significant (P<0.05) up-regulation of AnRs was also observed. Our data demonstrate that long-term treatment with anabolic compounds markedly affects receptor concentrations in target organs of male veal calves. Thus, studies investigating biological assays as screening methods to detect such compounds should be encouraged.

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.

Long-acting beta2-agonists for chronic asthma in adults and children where background therapy contains varied or no inhaled corticosteroid

BACKGROUND

Asthma is a common respiratory disease among both adults and children and short acting inhaled beta-2 agonists are used widely for 'reliever' bronchodilator therapy. Long acting beta-2 agonists (LABA) were introduced as prospective 'symptom controllers' in addition to inhaled corticosteroid 'preventer' therapy (ICS). In this updated review we have included studies in which patients were either not on ICS as a group, or in which some patients, but not all, were on ICS to complement previous systematic reviews of studies where LABA was given in patients uniformly receiving ICS. We have focussed particularly on serious adverse events, given previous concerns about potential risks, especially of death, from regular beta-2 agonist use.

OBJECTIVES

This review aimed to determine the benefit or detriment on the primary outcome of asthma control with the regular use of LABA compared with placebo, in mixed populations in which only some were taking ICS and in populations not using ICS therapy.

SEARCH STRATEGY

We carried out searches using the Cochrane Airways Group trial register, most recently in October 2005. We searched bibliographies of identified RCTs for additional relevant RCTs and contacted authors of identified RCTs for other published and unpublished studies.

SELECTION CRITERIA

All randomised studies of at least four weeks duration, comparing a LABA given twice daily with a placebo, in chronic asthma. Selection criteria to this updated review have been altered to accommodate recently published Cochrane reviews on combination and addition of LABA to ICS therapy. Studies in which all individuals were uniformly taking ICS were excluded from this review.

DATA COLLECTION AND ANALYSIS

Two reviewers performed data extraction and study quality assessment independently. We contacted authors of studies for missing data.

MAIN RESULTS

Sixty-seven studies (representing 68 experimental comparisons) randomising 42,333 participants met the inclusion criteria. Salmeterol was used as long-acting agent in 50 studies and formoterol fumarate in 17. The treatment period was four to nine weeks in 29 studies, and 12 to 52 weeks in 38 studies. Twenty-four studies did not permit the use of ICS, and forty permitted either inhaled corticosteroid or cromones (in three studies this was unclear). In these studies between 22% and 92% were taking ICS, with a median of 62%. There were significant advantages to LABA treatment compared to placebo for a variety of measurements of airway calibre including morning peak expiratory flow (PEF), evening PEF and FEV1. They were associated with significantly fewer symptoms, less use of rescue medication and higher quality of life scores. This was true whether patients were taking LABA in combination with ICS or not. Findings from SMART (a recently published surveillance study) indicated significant increases in asthma related deaths, respiratory related deaths and combined asthma related deaths and life threatening experiences. The absolute increase in asthma-related mortality was consistent with an increase of around one per 1250 patients treated with LABA for six months, but the confidence intervals are wide (from 700 to 10,000). Post-hoc exploratory subgroups suggested that African-Americans and those not on inhaled corticosteroids were at particular risk for the primary end-point of death or life-threatening asthma event. There was also a suggestion of an increase in exacerbation rate in children. Pharmacologically predicted side effects such as headache, throat irritation, tremor and nervousness were more frequent with LABA treatment.

AUTHORS' CONCLUSIONS

LABA are effective in the control of chronic asthma in the "real-life" subject groups included. However there are potential safety issues which call into question the safety of LABA, particularly in those asthmatics who are not taking ICS, and it is not clear why African-Americans were found to have significant differences in comparison to Caucasians for combined respiratory-related death and life threatening experiences, but not for asthma-related death.

Overview of the pharmacogenetics of asthma treatment

Asthma affects approximately 300 million individuals worldwide. Medications comprise a substantial portion of asthma expenditures. Despite the availability of three primary therapeutic classes of medications, there are a significant number of nonresponders to therapy. Available data, as well as previous pharmacogenetic studies, suggest that genetics may contribute as much as 60-80% to the interindividual variability in treatment response. In this methodologic review, after providing a broad overview of the asthma pharmacogenetics literature to date, we describe the application of a novel family-based screening algorithm to the analysis of pharmacogenetic data and highlight our approach to identifying and verifying loci influencing asthma treatment response. This approach seeks to address issues related to multiple comparisons, statistical power, population stratification, and failure to replicate from which previous population-based or case-control pharmacogenetic association studies may suffer. Identification of such replicable loci is the next step towards the goal of 'individualized therapy' for asthma.

Changes in lymphocyte glucocorticoid and beta-adrenergic receptors in veal calves treated with clenbuterol and steroid hormones for growth-promoting purposes*

In order to identify possible peripheral markers of illegal treatments with growth-promoting agents in veal calves, beta-adrenergic receptor (beta-AR) and glucocorticoid receptor (GR) concentrations were measured in lymphocytes of 12 male Friesian crossbred calves (six controls and six treated). The animals received a cocktail of anabolic and re-partitioning agents [17beta-oestradiol: 3 x 10 mg intramuscular (i.m.) doses at 17-day intervals; dexamethasone sodium phosphate: 4 mg/day for 6 days and 5 mg/day for six further days dissolved in milk; and clenbuterol: 20 microg/kg/day dissolved in milk for the last 40 days before slaughter]. Blood samples were collected by venipuncture at different time points and lymphocytes were isolated by density gradient centrifugation. Lymphocyte beta-AR and GR levels were measured by binding assays. Treatment with re-partitioning agents caused a significant down-regulation of lymphocyte beta-ARs 19 days after the beginning of clenbuterol administration and at day 55 (after dexamethasone withdrawal, just before slaughter). This phenomenon was partially reversed at day 50, after dexamethasone administration, at which time a significant decrease in GR concentrations also occurred. For both types of receptors, no significant changes in the dissociation constant values were observed at any time point. Lymphocytes express measurable concentrations of beta-ARs and GRs and the measurement of receptor levels highlights the fluctuation of receptor expression due to the dynamic interaction of the drugs used in combination. Lymphocyte receptor determination could therefore be included in a battery of biological assays to detect illegal treatments with anabolic agents in veal calves in the light of a multivariate approach.

Adding salmeterol to an inhaled corticosteroid: long term effects on bronchial inflammation in asthma

BACKGROUND

Addition of the long acting beta2 agonist salmeterol to inhaled corticosteroids leads to better symptomatic asthma control than increasing the dose of inhaled corticosteroids. However, little is known about the long term effects of adding salmeterol on the asthmatic inflammatory process, control of which is considered important for the long term outcome of asthma.

METHODS

After a 4 week fluticasone run-in period, 54 patients with allergic asthma were randomised to receive twice daily treatment with fluticasone 250 microg with or without salmeterol 50 microg for 1 year in a double blind, parallel group design (total daily dose of fluticasone 500 microg in both treatment groups). Primary outcomes were sputum eosinophil numbers and eosinophil cationic protein concentrations. Secondary outcomes were neutrophil associated sputum parameters and a respiratory membrane permeability marker. The effects on allergen induced changes were determined before and at the end of the treatment period.

RESULTS

Adding salmeterol to fluticasone resulted in improved peak expiratory flow, symptom scores, rescue medication usage, and bronchial hyperresponsiveness (p < 0.05 for all). There was no sustained effect on sputum cell differential counts and cytokine concentrations during the treatment period or on changes induced by allergen challenge at the end of treatment (p > 0.05). However, adding salmeterol significantly reduced sputum ratios of alpha2-macroglobulin and albumin during the treatment period (p = 0.001).

CONCLUSIONS

The addition of salmeterol to fluticasone produces no sustained effect on allergen induced cellular bronchial inflammation but leads to a significant improvement in size selectivity of plasma protein permeation across the respiratory membrane. This may contribute to the improved clinical outcome seen in patients with allergic asthma when a long acting beta2 agonist is combined with inhaled corticosteroids.

Budesonide and formoterol combination for the treatment of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality throughout the world. Current guidelines recommend the addition of inhaled steroids to bronchodilators, which are central to the symptomatic management of COPD in patients with severe disease. Budesonide/formoterol is a combination inhaled steroid and long-acting bronchodilator delivered by a dry-powder inhaler, approved for use in COPD. Two large, randomised, double-blind, 12-month studies found that combination budesonide/formoterol is more effective than either component alone in addressing many important aspects of the disease, such as pulmonary function, symptoms, use of relief medication, health-related quality of life and exacerbation in patients suffering from severe COPD. This review discusses the pharmacological and clinical properties of the drug.

Adding salmeterol to an inhaled corticosteroid reduces allergen-induced serum IL-5 and peripheral blood eosinophils

BACKGROUND

Adding a long-acting beta(2)-agonist to inhaled corticosteroids results in better symptomatic asthma control than increasing the dose of inhaled corticosteroids.

OBJECTIVE

Investigating whether adding the long-acting beta(2)-agonist salmeterol to the inhaled corticosteroid fluticasone propionate has an effect on allergen-induced allergic inflammation in asthma.

METHODS

Bronchial allergen challenges were performed in 26 patients with allergic asthma, pretreating them with a single dose of either fluticasone/salmeterol (100/50 microg) or fluticasone alone (100 microg), in a double-blind, randomized, cross-over design. Sputum and serum markers of bronchial inflammation were measured after allergen challenge, as well as lung function parameters. Primary outcomes were sputum eosinophil numbers and eosinophil cationic protein.

RESULTS

Asthmatic responses after allergen challenge were significantly reduced after pretreatment with fluticasone/salmeterol relative to fluticasone alone. Sputum inflammatory markers after allergen challenge were not significantly affected by fluticasone/salmeterol pretreatment. By contrast, serum IL-5 was significantly reduced (geometric mean serum IL-5 [SEM]: 0.5 [0.3] vs 1.1 [0.3] pg/mL 1 hour and 0.6 [0.3] vs 1.1 [0.3] pg/mL 6 hours after challenge with fluticasone/salmeterol vs fluticasone alone pretreatment, respectively; P values < .05). Also, peripheral blood eosinophils were significantly reduced (geometric mean number x 10(6)/L [SEM]: 172 [0.1] vs 237 [0.1] at 6 hours and 271 [0.1] vs 351 [0.1] at 24 hours with fluticasone/salmeterol vs fluticasone alone pretreatment, respectively; P < .05).

CONCLUSION

Adding salmeterol to fluticasone reduces allergen-induced serum IL-5 and peripheral blood eosinophils. This phenomenon may contribute to the improved clinical outcomes that result from adding a long-acting beta(2)-agonist to inhaled corticosteroids.

Fluticasone propionate/salmeterol for the treatment of chronic-obstructive pulmonary disease

Chronic-obstructive pulmonary disease (COPD) is a global public health problem and its impact is increasing. Although only smoking cessation has been shown to alter the natural history of the disease, current treatment guidelines recommend the use of inhaled bronchodilators to decrease symptoms, improve lung function and quality of life and to prevent exacerbations. For a subset of patients with more severe disease, inhaled corticosteroids may also have a role in achieving these goals. Fluticasone propionate/salmeterol (Advair) or Seretide), GlaxoSmithKline) is a combination inhaled steroid and long-acting bronchodilator that is delivered by a dry-powder inhaler and was recently approved for use in COPD in the US. Fluticasone propionate/salmeterol is a potent bronchodilator and also appears to have important effects on the frequency of exacerbations and overall quality of life for some patients with COPD. Issues of patient selection as well as the pharmacology, efficacy and safety of the drug are discussed.

Long-acting beta2-agonists: comparative pharmacology and clinical outcomes

Salmeterol and formoterol are both long-acting beta(2)-adrenoceptor agonists (beta(2)-agonists). They both provide excellent bronchodilating and bronchoprotective effects in patients with asthma but their are some differences between these two long-acting beta(2)-agonists in vitro and in vivo. Formoterol has a greater potency and intrinsic activity than salmeterol, which can become especially apparent at higher doses than that clinically recommended, and in contracted bronchi. Long-term use of long-acting beta(2)-agonists can induce tolerance, which can be partially reversed with corticosteroids. Long-acting beta(2)-agonists have some anti-inflammatory effects in vitro, but data in vivo are less convincing. Compared with doubling the dose of inhaled corticosteroids, the addition of inhaled long-acting beta(2)-agonists to inhaled corticosteroids improves symptom control in patients with asthma and reduces both the exacerbation rate of asthma and hospital admission rate. No enhanced airway responsiveness or loss of perception of dyspnea has been observed with the use of inhaled long-acting beta(2)-agonists. Monotherapy with long-acting beta(2)-agonists is not recommended.

Maintenance pharmacotherapy of chronic obstructive pulmonary disease: an evidence-based approach

Chronic obstructive pulmonary disease (COPD) is a major public health problem and its impact is increasing. Only smoking cessation and oxygen for -hypoxaemic patients have been shown to alter mortality, but modern pharmacological therapies can improve symptoms, lung function and quality of life. Treatment guidelines emphasise the use of bronchodilators as first-line treatment for COPD but make few recommendations about choosing a specific agent. In this review, the results of recent studies are examined to provide evidence-based guidance for the selection of appropriate maintenance therapy. Guidelines also support the use of inhaled corticosteroids in patients with more advanced disease, and the role of these agents is discussed.

[Synergic effects of anti-inflammatory drugs in asthma]

Persistent asthma is a chronic airway inflammatory disease that requires treatment with anti-inflammatory drugs. Inhaled corticosteroids are the cornerstone of the treatment of airway inflammation. Clinical studies have shown that asthmatic patients treated with long-acting beta(2)-agonists and inhaled corticosteroids have more reduced exacerbations than those given higher doses of corticosteroids suggesting synergistic effects on the inflammatory process. The understanding of the molecular modes of action of these two classes of drugs explained part of the enhanced anti-inflammatory activity of the combination therapy. However, the production of cysteinyl-leukotrienes is not well controlled by corticosteroids. Anti-leukotrienes, by the blockade of the effects of cysteinyl-leukotrienes, exert therefore a complementary anti-inflammatory action.

Clenbuterol antagonizes glucocorticoid-induced atrophy and fibre type transformation in mice

Beta-agonists and glucocorticoids are frequently coprescribed for chronic asthma treatment. In this study the effects of 4 week treatment with beta-agonist clenbuterol (CL) and glucocorticoid dexamethasone (DEX) on respiratory (diaphragm and parasternal) and limb (soleus and tibialis) muscles of the mouse were studied. Myosin heavy chain (MHC) distribution, fibres cross sectional area (CSA), glycolytic (phosphofructokinase, PFK; lactate dehydrogenase, LDH) and oxidative enzyme (citrate synthase, CS; cytochrome oxidase, COX) activities were determined. Muscle samples were obtained from four groups of adult C57/B16 mice: (1) Control (2) Mice receiving CL (CL, 1.5 mg kg(-1) day(-1) in drinking water) (3) Mice receiving DEX (DEX, 5.7 mg kg(-1) day(-1) s.c.) (4) Mice receiving both treatments (DEX + CL). As a general rule, CL and DEX showed opposite effects on CSA, MHC distribution, glycolytic and mitochondrial enzyme activities: CL alone stimulated a slow-to-fast transition of MHCs, an increase of PFK and LDH and an increase of muscle weight and fibre CSA; DEX produced an opposite (fast-to-slow transition) change of MHC distribution, a decrease of muscle weight and fibre CSA and in some case an increase of CS. The response varied from muscle to muscle with mixed muscles, as soleus and diaphragm, being more responsive than fast muscles, as tibialis and parasternal. In combined treatments (DEX + CL), the changes induced by DEX or CL alone were generally minimized: in soleus, however, the effects of CL predominated over those of DEX, whereas in diaphragm DEX prevailed over CL. Taken together the results suggest that CL might counteract the unwanted effects on skeletal muscles of chronic treatment with glucocorticoids.

Budesonide/formoterol: in chronic obstructive pulmonary disease

Budesonide/formoterol is a fixed-dose combination of the corticosteroid budesonide and the long-acting beta2-agonist formoterol, and is inhaled via the Turbuhaler device. In two large, randomised, double-blind, 12-month studies, patients with severe chronic obstructive pulmonary disease (COPD) receiving budesonide/formoterol 320/9 microg twice daily had a significantly higher forced expiratory volume in 1 second (FEV1) and significantly higher morning and evening peak expiratory flow at trial endpoint than recipients of budesonide or placebo; FEV1 was significantly higher than with formoterol in the larger study. In both studies, the rate of COPD exacerbations and exacerbations requiring oral corticosteroids was significantly reduced with budesonide/formoterol versus formoterol and placebo. Moreover, the time to first exacerbation was significantly prolonged with budesonide/formoterol versus all other treatment arms in the larger study. At 12 months, significant improvements in health-related quality-of-life scores were seen with budesonide/formoterol versus placebo in both studies. The reduction in total and individual symptom scores was significantly greater with budesonide/formoterol than with budesonide or placebo in the smaller study. Budesonide/formoterol was generally well tolerated by patients with severe COPD. The tolerability profile of the combination was similar to that of the individual components with no increase in the incidence of adverse events.

Administration of Aerosolized Terbutaline and Budesonide Reduces Chlorine Gas–Induced Acute Lung Injury

BACKGROUND

The pathophysiology and treatment of chlorine gas-induced acute lung injury is poorly characterized and based on anecdotal data. This study aimed to assess the effects of aerosolized beta-2 adrenergic agonist and corticosteroid therapy on chlorine gas-induced lung injury.

METHODS

Anesthetized, ventilated pigs were exposed to chlorine gas (400 parts per million for 20 minutes), then assigned randomly 30 minutes later to receive aerosolized terbutaline, budesonide, terbutaline followed by budesonide or placebo (6 pigs in each group). Hemodynamics, gas exchange, and lung mechanics were evaluated for another 5 hours.

RESULTS

All the animals demonstrated an immediate increase in airway and pulmonary artery pressure as well as sharp drops in arterial oxygen tension (PaO2) and lung compliance (CL). Recovery of PaO2 and CL was greatest in the terbutaline plus budesonide group, but therapy with terbutaline and budesonide alone also was associated with significant improvement in PaO2 and CL, as compared with placebo.

CONCLUSIONS

Treatment of acute chlorine gas lung injury with aerosolized terbutaline followed by aerosolized budesonide improved lung function. Combined treatment was more effective than treatment with either drug alone.

Budesonide/formoterol for the treatment of asthma

Budesonide/formoterol (Symbicort), AstraZeneca plc) is a novel treatment for asthma, combining an inhaled corticosteroid - budesonide, and a long-acting beta(2)-agonist - formoterol, in a single inhaler, the Turbuhaler. Randomised, clinical studies in patients with asthma have demonstrated that budesonide/formoterol is more effective than the inhaled corticosteroids, budesonide and fluticasone alone, and at least as effective as both monocomponents in separate inhalers. Results from clinical studies suggest a synergistic effect when both drugs are administered via one inhaler, although the mechanisms for this are not fully understood. Budesonide/formoterol has a rapid onset of effect, apparent within 1 min of treatment, which is largely because of the properties of formoterol. Once- and twice-daily dosing with budesonide/formoterol are effective treatment options for patients with mild or moderate asthma. Studies have also shown that the beneficial safety profiles and dose relationships of both budesonide and formoterol allow dose adjustments of budesonide/formoterol in response to variations in the patient's asthma. Findings from the budesonide/formoterol adjustable maintenance dosing programme, comparing fixed and adjustable, symptom-guided dosing regimens, demonstrate that patients achieve equally good asthma control with adjustable dosing (from one inhalation twice-daily to more than four inhalations twice-daily), but at a significantly lower overall drug load. Adverse events, mainly expected inhaled corticosteroid and long-acting beta(2)agonist class effects, have been few in number and mild in nature. In addition, there is growing evidence that budesonide/formoterol is also effective in patients with chronic obstructive pulmonary disease. The future for treatment with budesonide/formoterol may include as-needed administration in addition to maintenance therapy.

Beta-adrenergic agonists inhibit corticosteroid-induced apoptosis of airway epithelial cells

Airway epithelial damage is a feature of persistent asthma. Treatment with inhaled and oral corticosteroids may suppress inflammation and gain clinical control despite continued epithelial damage. We have previously demonstrated that corticosteroids elicit apoptosis of airway epithelial cells in culture. beta-Adrenergic receptor agonists are commonly used in asthma therapy and can inhibit corticosteroid-induced apoptosis of eosinophils. We tested the hypothesis that beta-adrenergic agonists would inhibit corticosteroid-induced airway epithelial cell apoptosis in cultured primary airway epithelial cells and in the cell line 1HAEo-. Albuterol treatment inhibited dexamethasone-induced apoptosis completely but did not inhibit apoptosis induced by Fas receptor activation. The protective effect of albuterol was duplicated by two different analogs of protein kinase A. The protective effect was not associated with increased translocation of the glucocorticoid receptor to the nucleus nor with changes in glucocorticoid receptor-mediated transcriptional activation or repression. We demonstrate that beta-adrenergic agonists can inhibit corticosteroid-induced apoptosis but not apoptosis induced by Fas activation. These data suggest that one potential deleterious effect of corticosteroid therapy in asthma can be prevented by concomitant beta-adrenergic agonist treatment.

Epidermal growth factor upregulates beta-adrenergic receptor signaling in a human salivary cell line

The effects of epidermal growth factor (EGF) on the beta-adrenergic receptor-coupled adenylyl cyclase system were studied in a human salivary cell line (HSY). The beta-adrenergic agonist isoproterenol (10(-5) M) stimulated adenylyl cyclase activity by approximately 2-fold, and the isoproterenol response was increased 1.8-fold after prolonged (48 h) exposure to EGF (5 x 10(-10) M). In contrast, enzyme activation via stimulatory prostaglandin receptors and by agents acting on nonreceptor components of the adenylyl cyclase system was not enhanced by EGF. beta-Adrenergic receptor density, assessed by binding of the beta-adrenergic receptor antagonist (-)-[(125)I]iodopindolol, was increased threefold after EGF treatment. Competition binding studies with unlabeled antagonists selective for beta(1)- and beta(2)-adrenergic receptor subtypes indicated that the increase in (-)-[(125)I]iodopindolol binding sites induced by EGF reflected an increased number of beta(2)-adrenergic receptors. Likewise, Northern blot analysis of RNA from EGF-treated cells revealed selective induction of beta(2)-adrenergic receptor mRNA, which was blocked by the RNA synthesis inhibitor actinomycin D. The increase in beta-adrenergic receptor density produced by EGF was unaltered after phorbol ester-induced downregulation of protein kinase C (PKC). Enhancement of isoproterenol-responsive adenylyl cyclase activity and phosphorylation of mitogen-activated protein kinase (MAPK) by EGF were both blocked by the MAPK pathway inhibitor PD-98059. The results suggest that in HSY cells EGF enhances beta-adrenergic responsiveness by upregulating beta(2)-adrenergic receptor expression at the transcriptional level. Moreover, the stimulatory effect of EGF on beta(2)-adrenergic receptor signaling appears to be mediated by the MAPK pathway and independent of PKC activation.

Inhaled long acting beta agonists for stable chronic asthma

BACKGROUND

Asthma is a common respiratory disease among both adults and children and short acting inhaled beta-2 agonists are used widely for 'reliever' bronchodilator therapy. Long acting beta-2 agonists were introduced as prospective 'symptom controllers' in addition to inhaled corticosteroid 'preventer' therapy (ICS).

OBJECTIVES

This review aimed to determine the benefit or detriment on the primary outcome of asthma control with the regular use of long acting inhaled beta-2 agonists compared with placebo.

SEARCH STRATEGY

We carried out searches using the Cochrane Airways Group trial register, most recently in October 2002. We searched bibliographies of identified RCTs for additional relevant RCTs and contacted authors of identified RCTs for other published and unpublished studies.

SELECTION CRITERIA

All randomised studies of at least two weeks duration, comparing a long acting inhaled beta-agonist given twice daily with a placebo, in chronic asthma.

DATA COLLECTION AND ANALYSIS

Two reviewers performed data extraction and study quality assessment independently. We contacted authors of studies for missing data.

MAIN RESULTS

Eighty five studies met the inclusion criteria, 56 parallel group and 29 cross over design. Salmeterol xinafoate was used as long acting agent in 60 studies and formoterol fumarate in 25. The treatment period was two to four weeks in 32 studies, and 12 to 52 weeks in 53 studies. 34 study groups used concurrent inhaled corticosteroid treatment, 21 studies did not permit their use and 35 permitted either inhaled corticosteroid or cromones. There were significant advantages to long acting beta-2 agonist treatment compared to placebo for a variety of measurements of airway calibre including morning peak expiratory flow (PEF) (weighted mean difference (WMD) 26.78 L/min 95%CI 20.36 to 33.20), evening PEF (WMD 19.17 L/min 95%CI 11.63 to 26.73). They were associated with significantly fewer symptoms, less use of rescue medication and higher quality of life scores. The risk of exacerbation was lower in adults using regular inhaled corticosteroids.

REVIEWER'S CONCLUSIONS

Long acting beta-2 agonists are effective in the control of chronic asthma, and the evidence supports their use in addition to inhaled corticosteroids, as emphasised in current guidelines. Further research is needed on their use in children under 12 and in mild asthmatics not taking ICS.

Regular treatment with long acting beta agonists versus daily regular treatment with short acting beta agonists in adults and children with stable asthma

BACKGROUND

Selective beta-adrenergic agonists for use in asthma are: short acting (2-6 hours) and long acting (>12 hours). There has been little controversy about using short acting beta-agonists intermittently, but long acting beta-agonists are used regularly, and their regular use has been controversial.

OBJECTIVES

To determine the benefit or detriment of treatment with regular short- or long acting inhaled beta-agonists in chronic asthma.

SEARCH STRATEGY

A search was carried out using the Cochrane Airways Group register. Bibliographies of identified RCTs were searched for additional relevant RCTs. Authors of identified RCTs were contacted for other published and unpublished studies.

SELECTION CRITERIA

All randomised studies of at least two weeks duration, comparing a long acting inhaled beta-agonist given twice daily with any short acting inhaled beta-agonist of equivalent bronchodilator effectiveness given regularly in chronic asthma.

DATA COLLECTION AND ANALYSIS

Two reviewers performed data extraction and study quality assessment independently. Authors of studies were contacted for missing data.

MAIN RESULTS

31 studies met the inclusion criteria, 24 of parallel group and 7 cross over design. Salmeterol xinafoate was used as long acting agent in 22 studies and formoterol fumarate in 9. Salbutamol was the short acting agent used in 27 studies and terbutaline in 5. The treatment period was over 2 weeks in 29 studies, and at least 12 weeks in 20. 25 studies permitted a variety of co-intervention treatments, usually inhaled corticosteroid or cromones. One study did not permit inhaled corticosteroid. Long acting beta-agonists were significantly better than short acting for a variety of lung function measurements including morning PEF (Weighted Mean Difference (WMD) 33 l/min 95% CI 25, 42) or evening PEF (WMD 26 l/min 95% CI 18, 33); and had significantly lower scores for day and night time asthma symptom scores and percentage of days and nights without symptoms. They were also associated with a significantly lower use of rescue medication both during the day and night. Risk of exacerbations was not different between the two types of agent, but most studies were of short duration which limits the power to test for such differences.

REVIEWER'S CONCLUSIONS

Long acting inhaled beta-agonists have advantages across a wide range of physiological and clinical outcomes for regular treatment.

Long-acting beta-agonist treatment in patients with persistent asthma already receiving inhaled corticosteroids

International guidelines recommend that long-acting beta-agonists should be considered in patients who are symptomatic despite moderate doses of inhaled corticosteroids. When combined with inhaled corticosteroids they improve asthma symptoms and lung function and reduce exacerbations. The evidence suggests that they are well tolerated. However, they are less effective than inhaled corticosteroids as monotherapy and should not be used alone, although the addition of a long-acting beta-agonist may permit a small reduction in the corticosteroid dose. Both salmeterol and formoterol appear equally effective in improving asthma control. Formoterol, however, has a rapid onset of action and is now being promoted for the relief of acute asthma symptoms. Both drugs provide prolonged protection against exercise-induced bronchospasm. However, this effect rapidly diminishes with continuous therapy and if this is the main aim of treatment, intermittent use may be preferable. When compared with alternative treatments, inhaled long-acting beta-agonists are more effective in controlling asthma symptoms than either theophylline or antileukotriene agents. Bambuterol, an oral prodrug of terbutaline, appears to be as effective as the inhaled long-acting beta-agonists and has the advantage of once daily oral administration. However, the inhaled long-acting beta-agonists are less likely to have systemic adverse effects. There are theoretical concerns that regular beta-agonist treatment may lead to tolerance and a failure to respond to emergency asthma treatment. While there is no doubt that tolerance occurs, there is currently little evidence that this is a clinical problem. Insights into pharmacological as well as therapeutic interactions between inhaled corticosteroids and beta-agonists are providing justification for their use in combination. Guidelines for the management of patients with chronic persistent asthma are likely to require modification to reflect these developments.

Inhaled budesonide/formoterol combination

Current evidence suggests that the addition of the long acting inhaled beta2-agonist formoterol to low or moderate doses of the inhaled corticosteroid budesonide is effective in improving lung function and reducing the incidence of asthma exacerbations. Concurrent use of budesonide with formoterol does not result in any untoward interaction that affects the pharmacodynamic or pharmacokinetic profiles of the individual drugs, or their adverse effect profiles. The administration of combined budesonide/formoterol is effective in improving morning and evening peak expiratory flow rates in adults with persistent asthma. Control of asthma symptoms is also significantly improved. In children aged 4 to 17 years, combined budesonide/formoterol is effective in increasing both morning and evening peak expiratory flow rates and significantly improving forced expiratory volume in 1 second (FEV1). The most commonly encountered adverse effects in clinical trials with combination budesonide/formoterol therapy have been respiratory infection, pharyngitis and coughing. No adverse effects on pulse rate, blood pressure or serum potassium have been reported with combination therapy.