Different approaches in the treatment of obstructive pulmonary diseases

Animal models and mechanisms of tobacco smoke-induced chronic obstructive pulmonary disease (COPD)

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide, and its global health burden is increasing. COPD is characterized by emphysema, mucus hypersecretion, and persistent lung inflammation, and clinically by chronic airflow obstruction and symptoms of dyspnea, cough, and fatigue in patients. A cluster of pathologies including chronic bronchitis, emphysema, asthma, and cardiovascular disease in the form of hypertension and atherosclerosis variably coexist in COPD patients. Underlying causes for COPD include primarily tobacco use but may also be driven by exposure to air pollutants, biomass burning, and workplace related fumes and chemicals. While no single animal model might mimic all features of human COPD, a wide variety of published models have collectively helped to improve our understanding of disease processes involved in the genesis and persistence of COPD. In this review, the pathogenesis and associated risk factors of COPD are examined in different mammalian models of the disease. Each animal model included in this review is exclusively created by tobacco smoke (TS) exposure. As animal models continue to aid in defining the pathobiological mechanisms of and possible novel therapeutic interventions for COPD, the advantages and disadvantages of each animal model are discussed.

Multi-walled carbon nanotubes induce arachidonate 5-lipoxygenase expression and enhance the polarization and function of M1 macrophages in vitro

Fibrogenic carbon nanotubes (CNTs) induce the polarization of M1 and M2 macrophages in mouse lungs. Polarization of the macrophages regulates the production of proinflammatory and pro-resolving lipid mediators (LMs) to mediate acute inflammation and its resolution in a time-dependent manner. Here we examined the molecular mechanism by which multi-walled CNTs (MWCNTs, Mitsui-7) induce M1 polarization in vitro. Treatment of murine macrophages (J774A.1) with Mitsui-7 MWCNTs increased the expression of Alox5 mRNA and protein in a concentration- and time-dependent manner. The MWCNTs induced the expression of CD68 and that induction persisted for up to 3 days post-exposure. The expression and activity of inducible nitric oxide synthase, an intracellular marker of M1, were increased by MWCNTs. Consistent with M1 polarization, the MWCNTs induced the production and secretion of proinflammatory cytokines tumor necrosis factor-α and interleukin-1β, and proinflammatory LMs leukotriene B4 (LTB4) and prostaglandin E2 (PGE2). The cell-free media from MWCNT-polarized macrophages induced the migration of neutrophilic cells (differentiated from HL-60), which was blocked by Acebilustat, a specific leukotriene A4 hydrolase inhibitor, or LY239111, an LTB4 receptor antagonist, but not NS-398, a cyclooxygenase 2 inhibitor, revealing LTB4 as a major mediator of neutrophil chemotaxis from MWCNT-polarized macrophages. Knockdown of Alox5 using specific small hairpin-RNA suppressed MWCNT-induced M1 polarization, LTB4 secretion, and migration of neutrophils. Taken together, these findings demonstrate the polarization of M1 macrophages by Mitsui-7 MWCNTs in vitro and that induction of Alox5 is an important mechanism by which the MWCNTs promote proinflammatory responses by boosting M1 polarization and production of proinflammatory LMs.

Pharmacokinetics, metabolite profiling, safety, and tolerability of inhalation aerosol of 101BHG-D01, a novel, long-acting and selective muscarinic receptor antagonist, in healthy Chinese subjects

101BHG-D01 is a novel, long-acting, selective muscarinic receptor antagonist for the treatment of chronic obstructive pulmonary disease (COPD). A single-site, randomized, double-blind, placebo-controlled and dose-escalation study of 101BHG-D01 inhalation aerosol was conducted to evaluate its pharmacokinetics, metabolite profiling, safety and tolerability following the single inhaled doses ranged from 20 to 900 μg in healthy Chinese subjects. After inhalation, 101BHG-D01 was absorbed rapidly into plasma with the time to maximum concentration about 5 min, and eliminated slowly with the terminal phase half-life about 30 h. The cumulative excretion rates of 101BHG-D01 in feces and urine were about 30% and 2%, respectively, which showed the study drug was mainly excreted in feces. The maximum drug concentration and area under the plasma concentration-time curve increased with dose escalation in the range of 20-600 μg, but their values increased out of proportion to the whole studied doses. The main metabolic pathways were loss of phenyl group and hydroxylation. No metabolite that presented at greater than 10 percent of total drug-related exposure was observed. 101BHG-D01 was safe and well tolerated after administration. The study results indicate that 101BHG-D01 is a good candidate for the treatment of COPD and enable further clinical development in subsequent studies in patients. Clinical Trial Registration: http://www.chinadrugtrials.org.cn; Identifier: CTR20192058.

The pulmonary route as a way to drug repositioning in COVID-19 therapy

Introduction

The outbreak of the disease caused by the new coronavirus (COVID-19) has been affecting society's routine and its patterns of interaction worldwide, in addition to the impact on the global economy. To date, there is still no clinically effective treatment for this comorbidity, and drug repositioning might be a good strategy considering the established clinical safety profile. In this context, since COVID-19 affects the respiratory tract, a promising approach would be the pulmonary drug delivery.

Objective

Identify repurposing drug candidates for the treatment of COVID-19 based on the data of ongoing clinical trials and in silico studies and also assess their potential to be applied in formulations for pulmonary administration.

Method

A integrative literature review was conducted between June and July 2020, by extracting the results from Clinical Trials, PubMed, Web of Science and Science Direct databases.

Results

By crossing the results obtained from diverse sources, 21 common drugs were found, from which only 4 drugs presented studies of pulmonary release formulations, demonstrating the need for greater investment and incentive in this field.

Conclusion

Even though the lung is a target that facilitates viral infection and replication, formulations for pulmonary delivery of suitable drugs are still lacking for COVID-19 treatment. However, it is indisputable that the pandemic constitutes a concrete demand, with a profound impact on public health, and that, with the appropriate investments, it will give the pharmaceutical industry an opportunity to reinforce the pulmonary delivery field.

Epac Function and cAMP Scaffolds in the Heart and Lung

Evidence collected over the last ten years indicates that Epac and cAMP scaffold proteins play a critical role in integrating and transducing multiple signaling pathways at the basis of cardiac and lung physiopathology. Some of the deleterious effects of Epac, such as cardiomyocyte hypertrophy and arrhythmia, initially described in vitro, have been confirmed in genetically modified mice for Epac1 and Epac2. Similar recent findings have been collected in the lung. The following sections will describe how Epac and cAMP signalosomes in different subcellular compartments may contribute to cardiac and lung diseases.

Protection from Cigarette Smoke-Induced Lung Dysfunction and Damage by H2 Relaxin (Serelaxin)

Cigarette smoke (CS) is the major etiologic factor of chronic obstructive pulmonary disease (COPD), which is characterized by airway remodeling, lung inflammation and fibrosis, emphysema, and respiratory failure. The current therapies can improve COPD management but cannot arrest its progression and reduce mortality. Hence, there is a major interest in identifying molecules susceptible of development into new drugs to prevent or reduce CS-induced lung injury. Serelaxin (RLX), or recombinant human relaxin-2, is a promising candidate because of its anti-inflammatory and antifibrotic properties highlighted in lung disease models. Here, we used a guinea pig model of CS-induced lung inflammation, and remodeling reproducing some of the hallmarks of COPD. Animals exposed chronically to CS (8 weeks) were treated with vehicle or RLX, delivered by osmotic pumps (1 or 10 μg/day) or aerosol (10 μg/ml/day) during CS treatment. Controls were nonsmoking animals. RLX maintained airway compliance to a control-like pattern, likely because of its capability to counteract lung inflammation and bronchial remodeling. In fact, treatment of CS-exposed animals with RLX reduced the inflammatory recruitment of leukocytes, accompanied by a significant reduction of the release of proinflammatory cytokines (tumor necrosis factor α and interleukin-1β). Moreover, RLX was able to counteract the adverse bronchial remodeling and emphysema induced by CS exposure by reducing goblet cell hyperplasia, smooth muscle thickening, and fibrosis. Of note, RLX delivered by aerosol has shown a comparable efficacy to systemic administration in reducing CS-induced lung dysfunction and damage. In conclusion, RLX emerges as a new molecule to counteract CS-induced inflammatory lung diseases.