Anti-inflammatory effects of medications used for viral infection-induced respiratory diseases

Respiratory viruses like rhinovirus, influenza virus, respiratory syncytial virus, and coronavirus cause several respiratory diseases, such as bronchitis, pneumonia, pulmonary fibrosis, and coronavirus disease 2019, and exacerbate bronchial asthma, chronic obstructive pulmonary disease, bronchiectasis, and diffuse panbronchiolitis. The production of inflammatory mediators and mucin and the accumulation of inflammatory cells have been reported in patients with viral infection-induced respiratory diseases. Interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α, granulocyte-macrophage colony-stimulating factor, and regulated on activation normal T-cell expressed and secreted are produced in the cells, including human airway and alveolar epithelial cells, partly through the activation of toll-like receptors, nuclear factor kappa B and p44/42 mitogen-activated protein kinase. These mediators are associated with the development of viral infection-induced respiratory diseases through the induction of inflammation and injury in the airway and lung, airway remodeling and hyperresponsiveness, and mucus secretion. Medications used to treat respiratory diseases, including corticosteroids, long-acting β₂-agonists, long-acting muscarinic antagonists, mucolytic agents, antiviral drugs for severe acute respiratory syndrome coronavirus 2 and influenza virus, macrolides, and Kampo medicines, reduce the production of viral infection-induced mediators, including cytokines and mucin, as determined in clinical, in vivo, or in vitro studies. These results suggest that the anti-inflammatory effects of these medications on viral infection-induced respiratory diseases may be associated with clinical benefits, such as improvements in symptoms, quality of life, and mortality rate, and can prevent hospitalization and the exacerbation of chronic obstructive pulmonary disease, bronchial asthma, bronchiectasis, and diffuse panbronchiolitis.

Changes in the breath sound spectrum with bronchodilation in children with asthma

BACKGROUND

Breath sound parameters have been suggested to be new biomarkers of airway function in patients with asthma.

METHODS

We investigated the effect of bronchodilation on breath sound parameters in sixty-four children (mean age, 8.9 years; range, 6-16 years) using a breath sound analyzer. The breath sound parameters included frequency limiting 50% and 99% of the power spectrum (F₅₀ and F₉₉), roll-off from 600-1200 Hz (slope), and spectrum curve indices such as the ratios of the third and fourth power area to the total area of the power spectrum (P₃/P_T and P₄/P_T), total area under the curve (A₃/A_T and B₄/A_T), and the ratio of power and frequency at 50% and 75% of the highest frequency of the power spectrum (RPF₇₅ and RPF₅₀). Lung function was assessed using spirometry and the forced oscillation technique (FOT). All variables were assessed before and after inhalation of a β₂-agonist.

RESULTS

The spectrum curve indices, A₃/A_T, B₄/A_T, RPF₇₅, and RPF₅₀, showed statistically significant increase following β₂-agonist inhalation. The increase in RPF₅₀ was correlated with the decrease in the difference between resistance at 5 Hz and 20 Hz, R5-R20, measured by FOT. In the multiple regression analysis adjusted for the effect of ΔRPF₇₅, the changes in A₃/A_T and B₄/A_T were positively correlated with that in the forced expiratory volume in one second.

CONCLUSIONS

The spectrum curve indices indicated bronchodilation, and may be useful for the assessment of bronchial reversibility in children with asthma.

Acute cardiovascular safety of two formulations of beclometasone dipropionate/formoterol fumarate in COPD patients: A single-dose, randomised, placebo-controlled crossover study

INTRODUCTION

An extrafine combination of beclometasone dipropionate (BDP) and formoterol fumarate (FF) via a pressurised metered-dose inhaler (pMDI) has been commercially available for some years for the management of asthma and chronic obstructive pulmonary disease (COPD). A dry powder inhaler (DPI) formulation of extrafine BDP/FF is now also available. This study evaluated the cardiovascular safety of BDP/FF DPI in comparison to BDP/FF pMDI and placebo.

METHODS

Single-dose, partially-blind, randomised, placebo-controlled, 5-period crossover study. Main inclusion criteria: aged 40-75 years; moderate to severe COPD (post-bronchodilator FEV₁ 40-80% predicted, FEV₁/FVC <0.7). Patients received BDP/FF 200/12, 800/48 μg and placebo via DPI, and BDP/FF 200/12 and 800/48 μg via pMDI. In both devices, 200/12 μg is the therapeutic dose; 800/48 μg is supratherapeutic.

PRIMARY OBJECTIVE

to demonstrate non-inferiority between BDP/FF DPI and pMDI in average 4-h heart rate (HR_0-4h) at each dose level. Secondary variables included: HR_0-12h, HR peak and individual timepoint; QTcF interval; SBP and DBP AUC_0-12h; and potassium and glucose AUC_0-4h. Adverse events (AEs) were collected.

RESULTS

Forty-nine patients were randomised; 45 (92%) received all five treatments. Non-inferiority was demonstrated between the DPI and pMDI formulations at both doses (-0.2 bpm [95% CI -1.3, 0.9] for 200/12 μg and 0.6 bpm [-0.5, 1.7] for 800/48 μg). Although there were statistically significant treatment-placebo differences at both doses and with both devices (thus confirming assay sensitivity), these differences were small and well below 5 bpm for the 200/12 μg dose. The results for the secondary parameters (QTcF, glucose and potassium) further supported the therapeutic equivalence of the two treatments. At the therapeutic dose, there were no clinically relevant treatment-placebo differences in any parameter with either formulation. There was no increase in the proportion of patients reporting AEs whilst receiving therapeutic doses of BDF/FF (either formulation) compared with placebo.

CONCLUSIONS

Overall, this study provides reassurance over the cardiovascular safety of extrafine BDP/FF, both in a DPI and a pMDI formulation.

Exchange protein directly activated by cyclic AMP (EPAC) activation reverses neutrophil dysfunction induced by β2-agonists, corticosteroids, and critical illness

BACKGROUND

Neutrophils play a role in the pathogenesis of asthma, chronic obstructive pulmonary disease, and pulmonary infection. Impaired neutrophil phagocytosis predicts hospital-acquired infection. Despite this, remarkably few neutrophil-specific treatments exist.

OBJECTIVES

We sought to identify novel pathways for the restoration of effective neutrophil phagocytosis and to activate such pathways effectively in neutrophils from patients with impaired neutrophil phagocytosis.

METHODS

Blood neutrophils were isolated from healthy volunteers and patients with impaired neutrophil function. In healthy neutrophils phagocytic impairment was induced experimentally by using β2-agonists. Inhibitors and activators of cyclic AMP (cAMP)-dependent pathways were used to assess the influence on neutrophil phagocytosis in vitro.

RESULTS

β2-Agonists and corticosteroids inhibited neutrophil phagocytosis. Impairment of neutrophil phagocytosis by β2-agonists was associated with significantly reduced RhoA activity. Inhibition of protein kinase A (PKA) restored phagocytosis and RhoA activity, suggesting that cAMP signals through PKA to drive phagocytic impairment. However, cAMP can signal through effectors other than PKA, such as exchange protein directly activated by cyclic AMP (EPAC). An EPAC-activating analog of cAMP (8CPT-2Me-cAMP) reversed neutrophil dysfunction induced by β2-agonists or corticosteroids but did not increase RhoA activity. 8CPT-2Me-cAMP reversed phagocytic impairment induced by Rho kinase inhibition but was ineffective in the presence of Rap-1 GTPase inhibitors. 8CPT-2Me-cAMP restored function to neutrophils from patients with known acquired impairment of neutrophil phagocytosis.

CONCLUSIONS

EPAC activation consistently reverses clinical and experimental impairment of neutrophil phagocytosis. EPAC signals through Rap-1 and bypasses RhoA. EPAC activation represents a novel potential means by which to reverse impaired neutrophil phagocytosis.

Regulation of Akt-mTOR, ubiquitin-proteasome and autophagy-lysosome pathways in response to formoterol administration in rat skeletal muscle

Administration of β2-agonists triggers skeletal muscle anabolism and hypertrophy. We investigated the time course of the molecular events responsible for rat skeletal muscle hypertrophy in response to 1, 3 and 10 days of formoterol administration (i.p. 2000μg/kg/day). A marked hypertrophy of rat tibialis anterior muscle culminated at day 10. Phosphorylation of Akt, ribosomal protein S6, 4E-BP1 and ERK1/2 was increased at day 3, but returned to control level at day 10. This could lead to a transient increase in protein translation and could explain previous studies that reported increase in protein synthesis following β2-agonist administration. Formoterol administration was also associated with a significant reduction in MAFbx/atrogin-1 mRNA level (day 3), suggesting that formoterol can also affect protein degradation of MAFbx/atrogin1 targeted substrates, including MyoD and eukaryotic initiation factor-3f (eIF3-f). Surprisingly, mRNA level of autophagy-related genes, light chain 3 beta (LC3b) and gamma-aminobutyric acid receptor-associated protein-like 1 (Gabarapl1), as well as lysosomal hydrolases, cathepsin B and cathepsin L, was significantly and transiently increased after 1 and/or 3 days, suggesting that autophagosome formation would be increased in response to formoterol administration. However, this has to be relativized since the mRNA level of Unc-51-like kinase1 (Ulk1), BCL2/adenovirus E1B interacting protein3 (Bnip3), and transcription factor EB (TFEB), as well as the protein content of Ulk1, Atg13, Atg5-Atg12 complex and p62/Sqstm1 remained unchanged or was even decreased in response to formoterol administration. These results demonstrate that the effects of formoterol are mediated, in part, through the activation of Akt-mTOR pathway and that other signaling pathways become more important in the regulation of skeletal muscle mass with chronic administration of β2-agonists.