Comparison of albuterol to isoproterenol as a bronchodilator for use in pulmonary function testing

Is a diluted seawater-based solution safe and effective on human nasal epithelium?

PURPOSE

Nasal irrigation is an effective method for alleviating several nasal symptoms and regular seawater-based nasal irrigation is useful for maintaining nasal hygiene which is essential for appropriate functioning of the nose and for preventing airborne particles including some pollutants, pathogens, and allergens from moving further in the respiratory system. However, safety studies on seawater-based nasal irrigation are scarce. In this study, the safety and efficacy of a diluted isotonic seawater solution (Stérimar Nasal Hygiene, SNH) in maintaining nasal homeostasis were evaluated in vitro.

METHODS

Safety was assessed by measuring tissue integrity via transepithelial electrical resistance (TEER). Efficacy was measured by mucociliary clearance (MCC), mucin secretion, and tissue re-epithelization (wound repair) assays. All assays were performed using a 3D reconstituted human nasal epithelium model.

RESULTS

In SNH-treated tissues, TEER values were statistically significantly lower than the untreated tissues; however, the values were above the tissue integrity limit. SNH treatment significantly increased MCC (88 vs. 36 µm/s, p < 0.001) and mucin secretion (1717 vs. 1280 µg/ml, p < 0.001) as compared to untreated cultures. Faster wound closure profile was noted upon pre-SNH treatment as compared to classical isotonic saline solution pre-treatment (90.5 vs. 50.7% wound closure 22 h after wound generation).

CONCLUSION

SNH did not compromise the integrity of the nasal epithelium in vitro. Furthermore, SNH was effective for removal of foreign particles through MCC increase and for enhancing wound repair on nasal mucosa.

Increased β2-adrenoceptor phosphorylation in airway smooth muscle in severe asthma: possible role of mast cell-derived growth factors

The purpose of this study was to investigate whether growth factors produced by activated human lung mast cells (HLMCs) impair β₂ -adrenoceptor (β₂ -AR) function in human airway smooth muscle (ASM) cells. Protein array analysis confirmed the presence of various growth factors, including transforming growth factor (TGF)-β1, in the supernatants of high-affinity IgE receptor (FcεRI)-activated HLMCs which, when applied to ASM cells, impaired albuterol-induced cyclic adenosine monophosphate (cAMP) production, an effect that was prevented following neutralization of TGF-β1. This blunted β₂ -AR response was reproduced by treating ASM cells with TGF-β1 or fibroblast growth factor (FGF)-2, which induced β₂ -AR phosphorylation at tyrosine residues Tyr¹⁴¹ and Tyr³⁵⁰ , and significantly reduced the maximal bronchorelaxant responses to isoproterenol in human precision cut lung slices (PCLS). Finally, ASM cells isolated from severe asthmatics displayed constitutive elevated β₂ -AR phosphorylation at both Tyr¹⁴¹ and Tyr³⁵⁰ and a reduced relaxant response to albuterol. This study shows for the first time that abnormal β₂ -AR phosphorylation/function in ASM cells that is induced rapidly by HLMC-derived growth factors, is present constitutively in cells from severe asthmatics.

The effects of long-acting β2-agonists plus inhaled corticosteroids for early reversibility in patients with airway obstruction

BACKGROUND

Salbutamol, as a short-acting β2-agonist, was popularly used in the past for detection of reversibility in patients with airway obstruction when it was the only drug available in the treatment of airway obstruction. Today, the combination of long-acting β2-agonists (LABA) and inhaled glucocorticoids are the first choice of therapy, with or without the presence of reversibility, in patients with airway obstruction. We aimed to compare the efficacy of salbutamol and long acting β2-agonists plus inhaled glucocorticoids for early reversibility test in patients with airway obstruction.

METHODS

Symptomatic patients (cough, dyspnea, and/or wheezing) with airway obstruction according to pulmonary function testing (FEV1/FVC value less than 70% of expected) who had never used bronchodilators before or had not received short- or long-acting inhaled bronchodilator therapy within the most recent 12 hours were evaluated. Reversibility measurements were made by administering the combination of long-acting β2-agonists (LABA) and inhaled glucocorticoids after 15 minutes.

RESULTS

A total of 90 patients were evaluated. The mean age of patients was 57.3±17.7 (range, 8-88) years and the male-to-female ratio was 69/21. The baseline pulmonary function test results were mean FVC; 2,747±1,181 mL and 74.7%±21.4%, mean FEV1; 1,716±825 mL and 57.5%±19.0%, mean FEV1/FVC; 61.4%±7.4%. The bronchodilator drugs given before reversibility testing were as salmeterol/fluticasone (FTC/SAL), formoterol/budesonide (BUD/FOR), beclomethasone dipropionate/formoterol (BDP/FOR) and salbutamol (SLB) in 24, 22, 24 and 20 patients, respectively. The reversibility was positive in 33 (36.7%) patients. The absolute change and percentage of change in mean FEV1 were 206±252 mL, 13.2%±16.6% for FTC/SAL group, 273±201 mL, 14%±8% for BUD/FOR group, 240±151 mL, 18.7%±15.9% for BUD/FOR groupand 171±116 mL, 13.3%±11.8% for SLB group. There was no statistically significant for reversibilty results between LABAs/inhaledsteroids and SLB group. And the patients with positivere versibility test were significantly higher in both of BUD/FOR and BDP/FOR groups than SLB group.

CONCLUSIONS

We think that performance of an early reversibility test using the combination of a LABA and an inhaled corticosteroid for treatment would enhance both the education of the patient in using the device and the reliability of the drug. And, we suggest that: "you should make the reversibility test with Long-Acting β2-Agonists plus Inhaled Corticosteroids which used in treatment of obstructive lung diseases".

Evaluation of Alstonia scholaris leaves for broncho-vasodilatory activity

The present study demonstrates that the ethanol extract of Alstonia scholaris (Apocynaceae) leaves induced pronounced bronchodilatory activity in anaesthetized rats with the probable involvement of prostaglandins. However, in vitro preparations of guinea-pig trachea did not confirm this property, indicating that bronchodilation is not due to the direct tracheal smooth muscle relaxation. The vasodilatory activity of the extract was independent of adrenergic or muscarinic receptors or prostaglandins but was mainly via endothelial-derived relaxing factor, nitric oxide. The extract inhibited the spontaneous movements of rabbit jejunum and contractile effects of acetylcholine and histamine on guinea-pig ileum. Additionally, the extract caused marked reduction of barium chloride-, potassium chloride- and calcium chloride-induced contraction on guinea-pig ileum and pulmonary artery, implying a direct interference of plant extract with the influx of calcium ions into cells. However, the extract has no detectable effect on mobilization of intracellular calcium. These results coupled with the in vivo effects of ethanol extract reveal that the Alstonia scholaris leaves possess broncho-vasodilatory activity mediated presumably by prostaglandins, calcium antagonism and endothelium-derived relaxing factor(s).

A statistical approach for assessment of bronchodilator responsiveness in pulmonary function testing

OBJECTIVE

Because published criteria for bronchodilator responsiveness are based on population variability and compare only the single best measures before and after intervention, we hypothesized that the variability of the FEV1 and FEV3 of each patient would better determine that patient's responsiveness.

DESIGN AND INTERVENTIONS

Five 3-s forced expiratory maneuvers were used for each of 3 sequential portions of the study: baseline, after nebulized saline solution, and after nebulized albuterol.

SETTING

Clinical pulmonary function laboratory in a county/university teaching hospital.

PATIENTS

Fifty consecutive adult patients with obstruction referred for routine testing and thought to be able to complete the study. (The primary diagnoses were found to be equally divided between asthma, bronchitis, and emphysema; equal numbers had very severe, severe, moderate, mild, or minimal obstruction.)

MEASUREMENTS AND RESULTS

The primary finding was that 36 patients were found to be responders (consistent and statistically significant FEV1 and FEV3 improvement after albuterol). The 14 identified as nonresponders would have been so categorized by all other published criteria. For assessing responsiveness, we found FEV3 measures preferable to vital capacity measures, because the latter depends on the duration of the maneuver.

CONCLUSIONS

The percentage of responders identified is higher than recognized by any other published criteria. Most criteria would not have identified the responders with very severe or minimal airways obstruction.