Montelukast, Leukotriene Inhibitor, Reduces LPS-Induced Acute Lung Inflammation and Human Neutrophil Activation

Montelukast as a potential treatment for COVID-19

INTRODUCTION

Montelukast is a leukotriene inhibitor that is widely used to treat chronic asthma and allergic rhinitis. The drug interferes with molecular signaling pathways produced by leukotrienes in a variety of cells and tissues throughout the human body that lead to tightening of airway muscles, production of aberrant pulmonary fluid (airway edema), and in some cases, pulmonary inflammation.

AREAS COVERED

Montelukast has also been noted to have anti-inflammatory properties, suggesting it may have a role in the treatment of coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has been noted to induce misfiring of the immune system in some patients. A literature search of PubMed was performed to identify all relevant studies of montelukast and SARS-CoV-2 through 27 January 2023.

EXPERT OPINION

Montelukast has been the subject of small studies of SARS-CoV-2 and will be included in a large, randomized, double-blind, placebo-controlled study of outpatients with COVID-19 sponsored by the United States National Institutes of Health known as Accelerating COVID-19 Therapeutic Interventions and Vaccines-6. This paper reviews what is known about montelukast, an inexpensive, well-tolerated, and widely available medication, and examines the rationale for using this drug to potentially treat patients with COVID-19.

Leukotriene Inhibitors with dexamethasone show promise in the prevention of death in COVID-19 patients with low oxygen saturations

Introduction

COVID-19 is a major health threat around the world causing hundreds of millions of infections and millions of deaths. There is a pressing global need for effective therapies. We hypothesized that leukotriene inhibitors (LTIs), that have been shown to lower IL6 and IL8 levels, may have a protective effect in patients with COVID-19.

Methods

In this retrospective controlled cohort study, we compared death rates in COVID-19 patients who were taking a LTI with those who were not taking an LTI. We used the Department of Veterans Affairs (VA) Corporate Data Warehouse (CDW) to create a cohort of COVID-19-positive patients and tracked their use of LTIs between November 1, 2019 and November 11, 2021.

Results

Of the 1,677,595 cohort of patients tested for COVID-19, 189,195 patients tested positive for COVID-19. Forty thousand seven hundred one were admitted. 38,184 had an oxygen requirement and 1214 were taking an LTI. The use of dexamethasone plus a LTI in hospital showed a survival advantage of 13.5% (CI: 0.23%-26.7%; p < 0.01) in patients presenting with a minimal O₂Sat of 50% or less. For patients with an O₂Sat of <60 and <50% if they were on LTIs as outpatients, continuing the LTI led to a 14.4% and 22.25 survival advantage if they were continued on the medication as inpatients.

Conclusions

When combined dexamethasone and LTIs provided a mortality benefit in COVID-19 patients presenting with an O₂ saturations <50%. The LTI cohort had lower markers of inflammation and cytokine storm.

Double-blind placebo-controlled randomized clinical trial to assess the efficacy of montelukast in mild to moderate respiratory symptoms of patients with long COVID: E-SPERANZA COVID Project study protocol

Background

The coronavirus disease 2019 (COVID-19) pandemic continues to affect the globe. After 18 months of the SARS-CoV-2 emergence, clinicians have clearly defined a subgroup of patients with lasting, disabling symptoms. While big strides have been made in understanding the acute phase of SARS-CoV-2 infection, the pathophysiology of long COVID is still largely unknown, and evidence-based, effective treatments for this condition remain unavailable.

Objectives

To evaluate the efficacy of 10 mg oral montelukast every 24 h versus placebo in improving quality of life associated with mild to moderate respiratory symptoms in patients with long COVID as measured with the COPD Assessment Test (CAT) questionnaire. The secondary objectives will evaluate the effect of montelukast versus placebo on improving exercise capacity, COVID-19 symptoms (asthenia, headache, mental confusion or brain fog, ageusia, and anosmia), oxygen desaturation during exertion, functional status, and mortality.

Methods and analysis

Phase III, randomized, double-blind clinical trial. We will include 18- to 80-year-old patients with SARS-CoV-2 infection and mild to moderate respiratory symptoms lasting more than 4 weeks. Participants will be randomly allocated in a 1:1 ratio to the intervention (experimental treatment with 10 mg/day montelukast) or the control group (placebo group), during a 28-day treatment. Follow-up will finish 56 days after the start of treatment. The primary outcome will be health-related quality of life associated with respiratory symptoms according to the COPD Assessment Test 4 weeks after starting the treatment. The following are the secondary outcomes: (a) exercise capacity and oxygen saturation (1-min sit-to-stand test); (b) Post-COVID-19 Functional Status Scale; (c) other symptoms: asthenia, headache, mental confusion (brain fog), ageusia, and anosmia (Likert scale); (d) use of healthcare resources; (e) mortality; (f) sick leave duration in days; and (g) side effects of montelukast.

Ethics and dissemination

This study has been approved by the Clinical Research Ethics Committee of the IDIAPJGol (reference number 21/091-C). The trial results will be published in open access, peer-reviewed journals and explained in webinars to increase awareness and understanding about long COVID among primary health professionals.

Trial registration

ClinicalTrials.govNCT04695704. Registered on January 5, 2021. EudraCT number 2021-000605-24. Prospectively registered.

Levocetirizine and montelukast in the COVID-19 treatment paradigm

Levocetirizine, a third-generation antihistamine, and montelukast, a leukotriene receptor antagonist, exhibit remarkable synergistic anti-inflammatory activity across a spectrum of signaling proteins, cell adhesion molecules, and leukocytes. By targeting cellular protein activity, they are uniquely positioned to treat the symptoms of COVID-19. Clinical data to date with an associated six-month follow-up, suggests the combination therapy may prevent the progression of the disease from mild to moderate to severe, as well as prevent/treat many of the aspects of ‘Long COVID,’ thereby cost effectively reducing both morbidity and mortality. To investigate patient outcomes, 53 consecutive COVID-19 test (+) cases (ages 3–90) from a well-established, single-center practice in Boston, Massachusetts, between March – November 2020, were treated with levocetirizine and montelukast in addition to then existing protocols [2]. The data set was retrospectively reviewed. Thirty-four cases were considered mild (64%), 17 moderate (32%), and 2 (4%) severe. Several patients presented with significant comorbidities (obesity: n = 22, 41%; diabetes: n = 10, 19%; hypertension: n = 24, 45%). Among the cohort there were no exclusions, no intubations, and no deaths. The pilot study in Massachusetts encompassed the first COVID-19 wave which peaked on April 23, 2020 as well as the ascending portion of the second wave in the fall. During this period the average weekly COVID-19 case mortality rate (confirmed deaths/confirmed cases) varied considerably between 1 and 7.5% [37]. FDA has approved a multicenter, randomized, placebo-controlled, Phase 2 clinical trial design, replete with electronic diaries and laboratory metrics to explore scientific questions not addressed herein.

Nuclear factor-kappa B and its role in inflammatory lung disease

Nuclear factor-kappa B, involved in inflammation, host immune response, cell adhesion, growth signals, cell proliferation, cell differentiation, and apoptosis defense, is a dimeric transcription factor. Inflammation is a key component of many common respiratory disorders, including asthma, chronic obstructive pulmonary disease (COPD), bronchiectasis, and acute respiratory distress syndrome. Many basic transcription factors are found in NF-κB signaling, which is a member of the Rel protein family. Five members of this family c-REL, NF-κB2 (p100/p52), RelA (p65), NF-κB1 (p105/p50), RelB, and RelA (p65) produce 5 transcriptionally active molecules. Proinflammatory cytokines, T lymphocyte, and B lymphocyte cell mitogens, lipopolysaccharides, bacteria, viral proteins, viruses, double-stranded RNA, oxidative stress, physical exertion, various chemotherapeutics are the stimulus responsible for NF-κB activation. NF-κB act as a principal component for several common respiratory illnesses, such as asthma, lung cancer, pulmonary fibrosis, COPD as well as infectious diseases like pneumonia, tuberculosis, COVID-19. Inflammatory lung disease, especially COVID-19, can make NF-κB a key target for drug production.

Role of leukotriene pathway and montelukast in pulmonary and extrapulmonary manifestations of Covid-19: The enigmatic entity

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), the responsible agent for the coronavirus disease 2019 (Covid-19), has its entry point through interaction with angiotensin converting enzyme 2 (ACE2) receptors, highly expressed in lung type II alveolar cells and other tissues, like heart, pancreas, brain, and vascular endothelium. This review aimed to elucidate the potential role of leukotrienes (LTs) in the pathogenesis and clinical presentation of SARS-CoV-2 infection, and to reveal the critical role of LT pathway receptor antagonists and inhibitors in Covid-19 management. A literature search was done in PubMed, Scopus, Web of Science and Google Scholar databases to find the potential role of montelukast and other LT inhibitors in the management of pulmonary and extra-pulmonary manifestations triggered by SARS-CoV-2. Data obtained so far underline that pulmonary and extra-pulmonary manifestations in Covid-19 are attributed to a direct effect of SARS-CoV-2 in expressed ACE2 receptors or indirectly through NF-κB dependent induction of a cytokine storm. Montelukast can ameliorate extra-pulmonary manifestations in Covid-19 either directly through blocking of Cys-LTRs in different organs or indirectly through inhibition of the NF-κB signaling pathway.

Montelukast in hospitalized patients diagnosed with COVID-19

OBJECTIVE

Several therapeutic agents have been assessed for the treatment of COVID-19, but few approaches have been proven efficacious. Because leukotriene receptor antagonists, such as montelukast have been shown to reduce both cytokine release and lung inflammation in preclinical models of viral influenza and acute respiratory distress syndrome, we hypothesized that therapy with montelukast could be used to treat COVID-19. The objective of this study was to determine if montelukast treatment would reduce the rate of clinical deterioration as measured by the COVID-19 Ordinal Scale.

METHODS

We performed a retrospective analysis of COVID-19 confirmed hospitalized patients treated with or without montelukast. We used "clinical deterioration" as the primary endpoint, a binary outcome defined as any increase in the Ordinal Scale value from Day 1 to Day 3 of the hospital stay, as these data were uniformly available for all admitted patients before hospital discharge. Rates of clinical deterioration between the montelukast and non-montelukast groups were compared using the Fisher's exact test. Univariate logistic regression was also used to assess the association between montelukast use and clinical deterioration. A total of 92 patients were analyzed, 30 who received montelukast at the discretion of the treating physician and 62 patients who did not receive montelukast.

RESULTS

Patients receiving montelukast experienced significantly fewer events of clinical deterioration compared with patients not receiving montelukast (10% vs 32%, p = 0.022). Our findings suggest that montelukast associates with a reduction in clinical deterioration for COVID-19 confirmed patients as measured on the COVID-19 Ordinal Scale.

CONCLUSIONS

Hospitalized COVID-19 patients treated with montelukast had fewer events of clinical deterioration, indicating that this treatment may have clinical activity. While this retrospective study highlights a potential pathway for COVID-19 treatment, this hypothesis requires further study by prospective studies.

The Leukotriene Receptor Antagonist Montelukast as a Potential COVID-19 Therapeutic

The emergence and global impact of COVID-19 has focused the scientific and medical community on the pivotal influential role of respiratory viruses as causes of severe pneumonia, on the understanding of the underlying pathomechanisms, and on potential treatment for COVID-19. The latter concentrates on four different strategies: (i) antiviral treatments to limit the entry of the virus into the cell and its propagation, (ii) anti-inflammatory treatment to reduce the impact of COVID-19 associated inflammation and cytokine storm, (iii) treatment using cardiovascular medication to reduce COVID-19 associated thrombosis and vascular damage, and (iv) treatment to reduce the COVID-19 associated lung injury. Ideally, effective COVID-19 treatment should target as many of these mechanisms as possible arguing for the search of common denominators as potential drug targets. Leukotrienes and their receptors qualify as such targets: they are lipid mediators of inflammation and tissue damage and well-established targets in respiratory diseases like asthma. Besides their role in inflammation, they are involved in various other aspects of lung pathologies like vascular damage, thrombosis, and fibrotic response, in brain and retinal damages, and in cardiovascular disease. In consequence, leukotriene receptor antagonists might be potential candidates for COVID-19 therapeutics. This review summarizes the current knowledge on the potential involvement of leukotrienes in COVID-19, and the rational for the use of the leukotriene receptor antagonist montelukast as a COVID-19 therapeutic.

The assessment of the serum levels of TWEAK and prostaglandin F2α in COVID – 19

Background/aim

It is claimed that aberrant immune response has a more important role than the cytopathic effect of the virus in the morbidity and mortality of the coronavirus disease 2019 (COVID-19). We aimed to investigate the possible roles of tumor necrosis factor-like weak inducer of apoptosis (TWEAK)/Fn14 pathway and leukotrienes (LT) in uncontrolled immune response that occurs in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Materials and methods

This study included 25 asymptomatic patients and 35 patients with lung involvement who were diagnosed with COVID-19 as well as 22 healthy volunteers. Lung involvement was determined using computed-tomography. Serum TWEAK, LTE4, and prostaglandin F2α (PGF2α) levels were determined.

Results

Compared with the healthy control group, TWEAK, LTE4, and PGF2α levels were higher in the group of SARS-CoV-2 infection without lung involvement. In the group of SARS-CoV-2 infection with lung involvement, age, fibrinogen, sedimentation, C-reactive protein and ferritin, TWEAK, LTE4, and PGF2α levels were higher, and lymphocyte levels were lower compared with the asymptomatic group.

Conclusions

In the study, TWEAK and LTE4 levels increased in cases with COVID-19. These results support that TWEAK/Fn14 pathway and LT may involved in the pathology of aberrant immune response against SARS-CoV-2. Inhibition of each of these pathways may be a potential target in the treatment of COVID-19.

Montelukast Drug May Improve COVID-19 Prognosis: A Review of Evidence

With the lack of effective therapy, chemoprevention and vaccination, focusing on the immediate repurposing of existing drugs gives hope of curbing the pandemic. Interestingly, montelukast, a drug usually used in asthma, may be proposed as a potential adjuvant therapy in COVID-19. The aim of the present article was to review the properties of montelukast that could be beneficial in COVID-19. Ten experimentally supported properties were retrieved, either related to SARS-CoV-2 (antiviral properties, prevention of endotheliitis and of neurological disorders linked to SARS-CoV-2), and/or related to the host (improvement of atherogenic vascular inflammation, limitation of the ischemia/reperfusion phenomenon, improvement of respiratory symptoms), and/or related to serious COVID-19 outcomes (limitation of the cytokine storm, mitigation of acute respiratory distress syndrome), and/or related to tissue sequelae (antioxidant properties, anti-fibrosis effects). Based on gathered theoretical evidence, we argue that montelukast should be further tested to prevent and treat COVID-19 outcomes.

Effect of berberine on LPS-induced expression of NF-B/MAPK signalling pathway and related inflammatory cytokines in porcine intestinal epithelial cells

Berberine is an alkaloid extracted from medicinal plants such as Coptis chinensis and Phellodendron chinense. It possesses anti-inflammatory, anti-tumour and anti-oxidation properties, and regulates Glc and lipid metabolism. This study explored the mechanisms of the protective effects of berberine on barrier function and inflammatory damage in porcine intestinal epithelial cells (IPEC-J2) induced by LPS. We first evaluated the effects of berberine and LPS on cell viability. IPEC-J2 cells were treated with 5 μg/ml LPS for 1 h to establish an inflammatory model, and 75, 150 and 250 μg/ml berberine were used in further experiments. The expression of IL-1β, IL-6 and TNF-α was measured by RT-PCR. The key proteins of the NF-κB/MAPK signalling pathway (IκBα, p-IκBα, p65, p-p65, c-Jun N-terminal kinase (JNK), p-JNK, p38, p-p38, ERK1/2 and p-ERK1/2) were detected by Western blot. Upon exposure to LPS, IL-1β, IL-6 and TNF-α mRNA levels and p-IκBα p-p65 protein levels were significantly enhanced. Pre-treatment with berberine reduced the expression of inflammatory factors and was positively correlated with its concentration, and dose dependently inhibited the expression of IκBα, p-IκBα, p-p65, p-p38 and JNK. These results demonstrated that pre-treating intestinal epithelial cells with berberine was useful in preventing and treating diarrhoea induced by Escherichia coli in weaned pigs.

Ibudilast, a Phosphodiesterase-4 Inhibitor, Ameliorates Acute Respiratory Distress Syndrome in Neonatal Mice by Alleviating Inflammation and Apoptosis

Background

Acute respiratory distress syndrome (ARDS) is a sudden and serious disease with increasing morbidity and mortality rates. Phosphodiesterase 4 (PDE4) is a novel target for inflammatory disease, and ibudilast (IBU), a PDE4 inhibitor, inhibits inflammatory response. Our study investigated the effect of IBU on the pathogenesis of neonatal ARDS and the underlying mechanism related to it.

Material/Methods

Western blotting was performed to analyze the expression levels of PDE4, CXCR4, SDF-1, CXCR5, CXCL1, inflammatory cytokines, and proteins related to cell apoptosis. Hematoxylin-eosin staining was performed to observe the pathological morphology of lung tissue. Pulmonary edema score was used to assess the degree of lung water accumulation after pulmonary injury. Enzyme-linked immunosorbent assay (ELISA) was used to assess levels of inflammatory factors (TNF-α, IL-1β, IL-6, and MCP-1) in serum. TUNEL assay was used to detect apoptotic cells.

Results

Increased expression of PDE4 was observed in an LPS-induced neonatal ARDS mouse model, and IBU ameliorated LPS-induced pathological manifestations and pulmonary edema in lung tissue. In addition, IBU attenuated the secretion of inflammatory cytokines by inactivating the chemokine axis in the LPS-induced neonatal ARDS mouse model. Finally, IBU significantly reduced LPS-induced cell apoptosis in lung tissue.

Conclusions

IBU, a PDE4 inhibitor, protected against ARDS by interfering with pulmonary inflammation and apoptosis. Our findings provide a novel and promising strategy to regulate pulmonary inflammation in ARDS.

Interleukin-37 Attenuates Lipopolysaccharide (LPS)-Induced Neonatal Acute Respiratory Distress Syndrome in Young Mice via Inhibition of Inflammation and Cell Apoptosis

Background

Neonatal acute respiratory distress syndrome (ARDS) is a common clinical syndrome caused by lung immaturity and the abnormal synthesis of pulmonary surfactant in preterm newborns, and it has high morbidity and mortality rates. The present study investigated the roles of interleukin-37 (IL-37) in the pathogenesis of neonatal ARDS and the underlying biochemical mechanism.

Material/Methods

We used 6-day-old neonatal C57BL/6 mice to establish the ARDS model. Inflammatory cytokines levels were measured with enzyme-linked immunosorbent assay (ELISA) Kits. The pathological morphology of lung tissues was observed by hematoxylin-eosin (HE) staining. The expression levels of proteins were assessed by Western blotting and apoptotic cells were detected via TUNEL assay. Further, the expression of nucleotide-bound oligomerization domain (Nod)-like receptor P3 (NLRP3) was detected with immunohistochemistry and Western blotting.

Results

IL-37 attenuated lipopolysaccharide (LPS)-induced cell apoptosis and excessive inflammatory cytokines levels, including IL-1β, IL-8, TNF-α, and MCP-1, and ameliorated lung pathological manifestations in an LPS-induced neonatal ARDS model. Moreover, IL-37 suppressed the abnormal expression of proteins related to the CXCR4/SDF-1 chemokine axis and NLRP3 inflammasome pathway.

Conclusions

The present results suggest that IL-37 protect against LPS-induced lung injury through inhibition of inflammation and apoptosis in lung tissue in an LPS-induced neonatal ARDS model. Hence, IL-37 may be considered as a potential therapeutic agent for neonatal ARDS.

Acute 1-NP exposure induces inflammatory responses through activating various inflammatory signaling pathways in mouse lungs and human A549 cells

1-Nitropyrene (1-NP), a key component of fine particulate matter (PM2.5), is a representative of nitrated polycyclic aromatic hydrocarbons (NPAHs). The aim of this research is to investigate proinflammatory effects of acute 1-NP exposure in mouse lungs and human A549 cells. All mice except controls were intratracheally instilled with 1-NP (20 μg/mouse). A549 cell, a human lung cancer cell line, was cultured with or without 1-NP (5 μM). Acute 1-NP exposure elevated lung weight and caused infiltration of inflammatory cells, especially neutrophils in mouse lungs. Although it had little effect on serum TNF-α and KC, acute 1-NP exposure elevated the levels of TNF-α and KC in BALF. Correspondingly, acute 1-NP exposure upregulated pulmonary Il-1β, Il-6, Tnf-α and Kc. Mechanistically, acute 1-NP exposure activated nuclear factor kappa B (NF-κB) in mouse lungs and human A549 cells. Additionally, acute 1-NP exposure induced Akt phosphorylation in mouse lungs and human A549 cells. Moreover, acute 1-NP exposure induced phosphorylation of pulmonary JNK and ERK1/2, molecules of the mitogen-activated protein kinase (MAPK) pathway. This study provides evidence that acute 1-NP exposure induces inflammatory responses through activating various inflammatory signaling pathways in mouse lungs and human A549 cells.