Potential therapeutic role for statins in respiratory disease

Statin Use Is Associated With Protection Against Acute Cholangitis in Patients With Primary Sclerosing Cholangitis: A Multicenter Retrospective Cohort Study

INTRODUCTION

Patients with primary sclerosing cholangitis (PSC) are at increased risk of acute cholangitis. The epidemiological risks of cholangitis are poorly studied despite the high morbidity associated with this infection. The aim of this study was to understand the impact of statins on acute cholangitis in PSC.

METHODS

This multicenter, retrospective cohort study assessed data from 294 patients with PSC at Stanford Medical Center, Baylor Medical Center, and Valley Medical Center. Clinical factors associated with the development of cholangitis were identified using multivariable Cox regression.

RESULTS

The patients were predominantly male (68.7%) with a median age at enrollment of 48 years (interquartile range [IQR]: 31.0-60.8). Fifty patients (17.0%) were prescribed statins. The median follow-up time was 6 years (IQR: 2.0-12.0), in which 29.6% (n = 87) developed cholangitis. In multivariable analysis, statins were associated with an 81% reduction in cholangitis (HR 0.19, 95% confidence interval 0.03-0.64). Statins were associated with a lower adjusted incidence of cholangitis at 36 months compared with patients not on statin therapy (incidence of 2.8% vs 12.2%, P < 0.001). Statins were also associated with increased time-to-stricture ( P = 0.004), an outcome known to be associated with PSC complications.

DISCUSSION

Statin therapy is associated with reduced risk of cholangitis in PSC, possibly by delaying the time to develop dominant or high-grade strictures. In patients with PSC, use of statin therapy may be a beneficial modality to prevent the development of cholangitis and warrants further investigation.

Simvastatin and Rifaximin in Decompensated Cirrhosis: A Randomized Clinical Trial

Importance

There are no useful treatments to prevent the development of severe complications of liver cirrhosis. Simvastatin and rifaximin have shown beneficial effects in liver cirrhosis.

Objective

To assess whether simvastatin combined with rifaximin improves outcomes in patients with decompensated cirrhosis.

Design, Setting, and Participants

Double-blind, placebo-controlled, phase 3 trial conducted among patients with decompensated cirrhosis in 14 European hospitals between January 2019 and December 2022. The last date of follow-up was December 2022.

Interventions

Patients were randomly assigned to receive simvastatin, 20 mg/d, plus rifaximin, 1200 mg/d (n = 117), or identical-appearing placebo (n = 120) for 12 months in addition to standard therapy, stratified according to Child-Pugh class B or C.

Main Outcomes and Measures

The primary end point was incidence of severe complications of liver cirrhosis associated with organ failure meeting criteria for acute-on-chronic liver failure. Secondary outcomes included transplant or death and a composite end point of complications of cirrhosis (ascites, hepatic encephalopathy, variceal bleeding, acute kidney injury, and infection).

Results

Among the 237 participants randomized (Child-Pugh class B: n = 194; Child-Pugh class C: n = 43), 72% were male and the mean age was 57 years. There were no differences between the 2 groups in terms of development of acute-on-chronic liver failure (21 [17.9%] vs 17 [14.2%] patients in the treatment and placebo groups, respectively; hazard ratio, 1.23; 95% CI, 0.65-2.34; P = .52); transplant or death (22 [18.8%] vs 29 [24.2%] patients in the treatment and placebo groups, respectively; hazard ratio, 0.75; 95% CI, 0.43-1.32; P = .32); or development of complications of cirrhosis (50 [42.7%] vs 55 [45.8%] patients in the treatment and placebo groups, respectively; hazard ratio, 0.93; 95% CI, 0.63-1.36; P = .70). Incidence of adverse events was similar in both groups (426 vs 419; P = .59), but 3 patients in the treatment group (2.6%) developed rhabdomyolysis.

Conclusions and Relevance

The addition of simvastatin plus rifaximin to standard therapy does not improve outcomes in patients with decompensated liver cirrhosis.

Trial Registration

ClinicalTrials.gov Identifier: NCT03780673.

Cholesterol Accumulation Enhances Cigarette Smoke-Induced Airway Epithelial Inflammation

Background

Statins, commonly used to lower cholesterol, have been shown to have anti-inflammatory effects in respiratory disease models. Disorders of cholesterol metabolism can cause damage to cells and tissues, and further lead to the development of a variety of diseases. However, the role of cholesterol metabolism in cigarette smoke-induced airway epithelial inflammation is unclear. The present study aims to explore this question.

Methods

Human bronchial epithelial cells (HBEs) were stimulated with cigarette smoke extract (CSE) and mice were exposed to CS as models. The expression of cholesterol content and cholesterol metabolism-related molecules such as Sterol Regulatory Element-Binding Protein 2 (SREBP2), 3-Hydroxy-3-Methylglutaryl-CoA Reductase (HMGCR), ATP Binding Cassette Transporter A1 (ABCA1), and ATP Binding Cassette Transporter G1 (ABCG1) were detected by cholesterol assay kits and immunohistochemistry (IHC) in vivo, and were detected by cholesterol assay kits, Western blot (WB), and quantitative real-time polymerase chain reaction (Q-PCR) in vitro. Cholesterol metabolism molecules related siRNAs, inhibitors or agonists were used to intervene the Cholesterol levels in HBE. The mRNA level and protein level of interleukin IL-6 and IL-8 were detected by RT-qPCR and enzyme-linked immunosorbent assay (ELISA). Cellular reactive oxygen species (ROS) levels were detected by reactive oxygen species assay kits.

Results

We found that cigarette smoke exposure inhibited cholesterol efflux by decreasing the expression of ABCA1, thereby increasing cholesterol accumulation in airway epithelial cells, which promotes the production of reactive oxygen species and promotes the secretion of inflammatory cytokines, ultimately aggravating cigarette smoke-induced airway inflammation. Reducing intracellular cholesterol content by inhibiting intracellular synthesis and promoting increased efflux can reduce the cigarette smoke-induced airway epithelial inflammatory factors secretion.

Conclusion

In conclusion, cholesterol accumulation plays an important role in cigarette smoke-induced airway inflammation and may provide new targets in the treatment of this disease in the future.

Adjunctive Statin Therapy in Patients with Covid-19: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The efficacy and safety of adjunctive statin therapy in hospitalized patients with coronavirus disease 2019 (Covid-19) remains uncertain.

METHODS

We systematically searched Medline, Embase, Cochrane, and ClinicalTrials.gov databases from inception to late April 2024 for randomized controlled trials (RCTs) comparing statin versus no statin use in patients hospitalized with Covid-19. We pooled risk ratios (RRs) and hazard ratios (HRs) with 95% confidence intervals (CIs) applying a random-effects model. R version 4.3.1 was used for statistical analyses.

RESULTS

We included 7 RCTs comprising 4,262 patients, of whom 2,645 (62%) were randomized to receive statin therapy. Compared with no statin, statin use significantly reduced case-fatality rate (RR 0.88; 95% CI 0.80-0.98; I2 = 0%). In a time-to-event analysis, we found similar results (HR 0.86; 95% CI 0.75-0.99; I2 = 0%). Statin use also significantly reduced World Health Organization (WHO) scale at 14 days (mean difference -0.27; 95% CI -0.54 to -0.01; I2 = 0%). There was no statistically significant difference between the two groups in length of hospital stay, elevation of liver enzymes, and C-reactive protein levels.

CONCLUSIONS

In patients hospitalized with Covid-19, statins significantly reduced case-fatality rate and WHO scale score.

REGISTRATION

A prospective register was recorded in International Prospective Register of Systematic Reviews (PROSPERO) with the number CRD42023479007.

Early Detection of Atrial Fibrillation in Chronic Obstructive Pulmonary Disease Patients

Atrial fibrillation (AF) is an important medical problem, as it significantly affects patients' quality of life and prognosis. AF often complicates the course of chronic obstructive pulmonary disease (COPD), a widespread disease with heavy economic and social burdens. A growing body of evidence suggests multiple links between COPD and AF. This review considers the common pathogenetic mechanisms (chronic hypoxia, persistent inflammation, endothelial dysfunction, and myocardial remodeling) of these diseases and describes the main risk factors for the development of AF in patients with COPD. The most effective models based on clinical, laboratory, and functional indices are also described, which enable the identification of patients suffering from COPD with a high risk of AF development. Thus, AF in COPD patients is a frequent problem, and the search for new tools to identify patients at a high risk of AF among COPD patients remains an urgent medical problem.

Cardiomyopathy in cirrhosis: From pathophysiology to clinical care

Cirrhotic cardiomyopathy (CCM) is defined as systolic or diastolic dysfunction in the absence of prior heart disease or another identifiable cause in patients with cirrhosis, in whom it is an important determinant of outcome. Its underlying pathogenic/pathophysiological mechanisms are rooted in two distinct pathways: 1) factors associated with portal hypertension, hyperdynamic circulation, gut bacterial/endotoxin translocation and the resultant inflammatory phenotype; 2) hepatocellular insufficiency with altered synthesis or metabolism of substances such as proteins, lipids, carbohydrates, bile acids and hormones. Different criteria have been proposed to diagnose CCM; the first in 2005 by the World Congress of Gastroenterology, and more recently in 2019 by the Cirrhotic Cardiomyopathy Consortium. These criteria mainly utilised echocardiographic evaluation, with the latter refining the evaluation of diastolic function and integrating global longitudinal strain into the evaluation of systolic function, an important addition since the haemodynamic changes that occur in advanced cirrhosis may lead to overestimation of systolic function by left ventricular ejection fraction. Advances in cardiac imaging, such as cardiac magnetic resonance imaging and the incorporation of an exercise challenge, may help further refine the diagnosis of CCM. Over recent years, CCM has been shown to contribute to increased mortality and morbidity after major interventions, such as liver transplantation and transjugular intrahepatic portosystemic shunt insertion, and to play a pathophysiologic role in the genesis of hepatorenal syndrome. In this review, we discuss the pathogenesis/pathophysiology of CCM, its clinical implications, and the role of cardiac imaging modalities including MRI. We also compare diagnostic criteria and review the potential diagnostic role of electrocardiographic QT prolongation. At present, no definitive medical therapy exists, but some promising potential treatment strategies for CCM are reviewed.

Beneficial role of kaempferol and its derivatives from different plant sources on respiratory diseases in experimental models

Respiratory illnesses impose a significant health burden and cause deaths worldwide. Despite many advanced strategies to improve patient outcomes, they are often less effective. There is still considerable room for improvement in the treatment of various respiratory diseases. In recent years, alternative medicinal agents derived from food plants have shown better beneficial effects against a wide variety of disease models, including cancer. In this regard, kaempferol (KMF) and its derivatives are the most commonly found dietary flavonols. They have been found to exhibit protective effects on multiple chronic diseases like diabetes, fibrosis, and so on. A few recent articles have reviewed the pharmacological actions of KMF in cancer, central nervous system diseases, and chronic inflammatory diseases. However, there is no comprehensive review that exists regarding the beneficial effects of KMF and its derivatives on both malignant- and non-malignant respiratory diseases. Many experimental studies reveal that KMF and its derivatives are helpful in managing a wide range of respiratory diseases, including acute lung injury, fibrosis, asthma, cancer, and chronic obstructive pulmonary disease, and their underlying molecular mechanisms. In addition, we also discussed the chemistry and sources, the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties, methods to enhance bioavailability, as well as our perspective on future research with KMF and its derivatives.

Atorvastatin and ezetimibe protect against hypercholesterolemia-induced lung oxidative stress, inflammation, and fibrosis in rats

Background

Hypercholesterolemia is a major risk factor for interstitial lung disease (ILD). Atorvastatin and ezetimibe are antilipemic drugs that have pleiotropic effects. However, their effects on pulmonary fibrosis prevention and the mechanisms underlying hypercholesterolemia have not been fully investigated. This study aimed to evaluate the individual effects of atorvastatin and ezetimibe on lung inflammation and fibrosis in high-cholesterol diet (HCD)-fed rats.

Materials and methods

Male Sprague-Dawley rats were divided into four groups — standard diet (S), standard diet + 1% cholesterol (SC), standard diet + 1% cholesterol with 30 mg/kg/day atorvastatin (SCA), and standard diet + 1% cholesterol with 10 mg/kg/day ezetimibe (SCE). At the end of an 8-week dietary schedule, serum lipid parameters and the levels of lung oxidative stress, inflammatory cytokines, and fibrotic mediators were determined.

Results

Atorvastatin and ezetimibe treatment remarkably reduced serum lipid profiles with reversed pulmonary histological alterations, in addition to reducing the levels of lung oxidative stress, inflammation, and fibrosis in hypercholesterolemic rats.

Conclusion

Atorvastatin and ezetimibe treatment showed a protective effect against hypercholesterolemia-induced pulmonary fibrosis in rats. This information appears potentially useful in the prevention of PF in a hypercholesterolemia model; however, further rigorous investigations are needed to prove their clinical utility on antifibrosis.

Host-microbiome interactions: Gut-Liver axis and its connection with other organs

An understanding of connections between gut microbiome and liver has provided important insights into the pathophysiology of liver diseases. Since gut microbial dysbiosis increases gut permeability, the metabolites biosynthesized by them can reach the liver through portal circulation and affect hepatic immunity and inflammation. The immune cells activated by these metabolites can also reach liver through lymphatic circulation. Liver influences immunity and metabolism in multiple organs in the body, including gut. It releases bile acids and other metabolites into biliary tract from where they enter the systemic circulation. In this review, the bidirectional communication between the gut and the liver and the molecular cross talk between the host and the microbiome has been discussed. This review also provides details into the intricate level of communication and the role of microbiome in Gut-Liver-Brain, Gut-Liver-Kidney, Gut-Liver-Lung, and Gut-Liver-Heart axes. These observations indicate a complex network of interactions between host organs influenced by gut microbiome.

Acute respiratory distress syndrome: causes, pathophysiology, and phenotypes

Acute respiratory distress syndrome (ARDS) is a common clinical syndrome of acute respiratory failure as a result of diffuse lung inflammation and oedema. ARDS can be precipitated by a variety of causes. The pathophysiology of ARDS is complex and involves the activation and dysregulation of multiple overlapping and interacting pathways of injury, inflammation, and coagulation, both in the lung and systemically. Mechanical ventilation can contribute to a cycle of lung injury and inflammation. Resolution of inflammation is a coordinated process that requires downregulation of proinflammatory pathways and upregulation of anti-inflammatory pathways. The heterogeneity of the clinical syndrome, along with its biology, physiology, and radiology, has increasingly been recognised and incorporated into identification of phenotypes. A precision-medicine approach that improves the identification of more homogeneous ARDS phenotypes should lead to an improved understanding of its pathophysiological mechanisms and how they differ from patient to patient.

The association between visceral adiposity with systemic inflammation, oxidative stress, and risk of post-surgical adhesion

Abdominal and pelvic adhesions are common post-operative complications. Despite new medical technologies, these adhesions are appearing to be unavoidable and little is known about their causation; for example, why certain patients/or tissues are more prone to adhesions. There have been no clinical studies about increasing the risk adhesions in obese patients, but there is some evidence about the molecular mechanisms involving visceral fat (VF) that may lead to profibrotic conditions. VF is an endocrine/inflammatory organ which produces many biologically active molecules such as adipokines and inflammatory cytokines. Inflammatory conditions, oxidative stress, and the expression some fibrotic molecules in the VF may induce pathological conditions in the abdominal cavity that predispose to the formation of fibrotic bands.

Simvastatin Downregulates the SARS-CoV-2-Induced Inflammatory Response and Impairs Viral Infection Through Disruption of Lipid Rafts

Coronavirus disease 2019 (COVID-19) is currently a worldwide emergency caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). In observational clinical studies, statins have been identified as beneficial to hospitalized patients with COVID-19. However, experimental evidence of underlying statins protection against SARS-CoV-2 remains elusive. Here we reported for the first-time experimental evidence of the protective effects of simvastatin treatment both in vitro and in vivo. We found that treatment with simvastatin significantly reduced the viral replication and lung damage in vivo, delaying SARS-CoV-2-associated physiopathology and mortality in the K18-hACE2-transgenic mice model. Moreover, simvastatin also downregulated the inflammation triggered by SARS-CoV-2 infection in pulmonary tissue and in human neutrophils, peripheral blood monocytes, and lung epithelial Calu-3 cells in vitro, showing its potential to modulate the inflammatory response both at the site of infection and systemically. Additionally, we also observed that simvastatin affected the course of SARS-CoV-2 infection through displacing ACE2 on cell membrane lipid rafts. In conclusion, our results show that simvastatin exhibits early protective effects on SARS-CoV-2 infection by inhibiting virus cell entry and inflammatory cytokine production, through mechanisms at least in part dependent on lipid rafts disruption.

Atorvastatin versus placebo in patients with covid-19 in intensive care: randomized controlled trial

OBJECTIVE

To assess the effect of statin treatment versus placebo on clinical outcomes in patients with covid-19 admitted to the intensive care unit (ICU).

DESIGN

INSPIRATION/INSPIRATION-S was a multicenter, randomized controlled trial with a 2×2 factorial design. Results for the anticoagulation randomization have been reported previously. Results for the double blind randomization to atorvastatin versus placebo are reported here.

SETTING

11 hospitals in Iran.

PARTICIPANTS

Adults aged ≥18 years with covid-19 admitted to the ICU.

INTERVENTION

Atorvastatin 20 mg orally once daily versus placebo, to be continued for 30 days from randomization irrespective of hospital discharge status.

MAIN OUTCOME MEASURES

The primary efficacy outcome was a composite of venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation, or all cause mortality within 30 days from randomization. Prespecified safety outcomes included increase in liver enzyme levels more than three times the upper limit of normal and clinically diagnosed myopathy. A clinical events committee blinded to treatment assignment adjudicated the efficacy and safety outcomes.

RESULTS

Of 605 patients randomized between 29 July 2020 and 4 April 2021 for statin randomization in the INSPIRATION-S trial, 343 were co-randomized to intermediate dose versus standard dose prophylactic anticoagulation with heparin based regimens, whereas 262 were randomized after completion of the anticoagulation study. 587 of the 605 participants were included in the primary analysis of INSPIRATION-S, reported here: 290 were assigned to atorvastatin and 297 to placebo (median age 57 years (interquartile range 45-68 years); 256 (44%) women). The primary outcome occurred in 95 (33%) patients assigned to atorvastatin and 108 (36%) assigned to placebo (odds ratio 0.84, 95% confidence interval 0.58 to 1.21). Death occurred in 90 (31%) patients in the atorvastatin group and 103 (35%) in the placebo group (odds ratio 0.84, 95% confidence interval 0.58 to 1.22). Rates for venous thromboembolism were 2% (n=6) in the atorvastatin group and 3% (n=9) in the placebo group (odds ratio 0.71, 95% confidence interval 0.24 to 2.06). Myopathy was not clinically diagnosed in either group. Liver enzyme levels were increased in five (2%) patients assigned to atorvastatin and six (2%) assigned to placebo (odds ratio 0.85, 95% confidence interval 0.25 to 2.81).

CONCLUSIONS

In adults with covid-19 admitted to the ICU, atorvastatin was not associated with a significant reduction in the composite of venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation, or all cause mortality compared with placebo. Treatment was, however, found to be safe. As the overall event rates were lower than expected, a clinically important treatment effect cannot be excluded.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04486508.

Evaluation of the efficiency of simvastatin loaded PLGA nanoparticles against acute paraquat-intoxicated rats

Here, we reported a novel nanotherapeutic platform for paraquat (PQ)-induced acute lung injury in animal models using simvastatin (SV) loaded into Poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs). In this way, Male Wistar rats orally received PQ (120 mg / kg) plus saline, SV (20 mg / kg) or PLGA-SV NPs containing 5, 10 and 20 mg SV/ kg. The levels of TNFα, IL-1β, IL-6 and glutathione content were evaluated. In addition, the pathological changes in the lung were monitored. Our results indicated that PQ (120 mg/kg) significantly reduced the body weight of rats compared to the control group. The most decrease in the level of inflammatory cytokines, bleeding, alveolar destruction as well as lymphocytic infiltration in the lung was observed at group treated with PLGA-SV NPs (10 mg). Free SV (20 mg) as well as PLGA-SV NPs (5 mg) modulated the inflammatory factors and glutathione content, however, they could not prevent tissue damage of PQ. Interestingly, PLGA-SV NPs (20 mg) could not improve the PQ- induced pulmonary damage. In conclusion, PLGA-SV NPs (10 mg) attenuated PQ-induced lung injury. The underlying mechanism may be relevant to increasing glutathione levels and inhibition of the production of inflammatory factors.

Statin Use and COVID-19 Infectivity and Severity in South Korea: Two Population-Based Nationwide Cohort Studies

Background

Basic studies suggest that statins as add-on therapy may benefit patients with COVID-19; however, real-world evidence of such a beneficial association is lacking.

Objective

We investigated differences in SARS-CoV-2 test positivity and clinical outcomes of COVID-19 (composite endpoint: admission to intensive care unit, invasive ventilation, or death) between statin users and nonusers.

Methods

Two independent population-based cohorts were analyzed, and we investigated the differences in SARS-CoV-2 test positivity and severe clinical outcomes of COVID-19, such as admission to the intensive care unit, invasive ventilation, or death, between statin users and nonusers. One group comprised an unmatched cohort of 214,207 patients who underwent SARS-CoV-2 testing from the Global Research Collaboration Project (GRCP)-COVID cohort, and the other group comprised an unmatched cohort of 74,866 patients who underwent SARS-CoV-2 testing from the National Health Insurance Service (NHIS)-COVID cohort.

Results

The GRCP-COVID cohort with propensity score matching had 29,701 statin users and 29,701 matched nonusers. The SARS-CoV-2 test positivity rate was not associated with statin use (statin users, 2.82% [837/29,701]; nonusers, 2.65% [787/29,701]; adjusted relative risk [aRR] 0.97; 95% CI 0.88-1.07). Among patients with confirmed COVID-19 in the GRCP-COVID cohort, 804 were statin users and 1573 were matched nonusers. Statin users were associated with a decreased likelihood of severe clinical outcomes (statin users, 3.98% [32/804]; nonusers, 5.40% [85/1573]; aRR 0.62; 95% CI 0.41-0.91) and length of hospital stay (statin users, 23.8 days; nonusers, 26.3 days; adjusted mean difference –2.87; 95% CI –5.68 to –0.93) than nonusers. The results of the NHIS-COVID cohort were similar to the primary results of the GRCP-COVID cohort.

Conclusions

Our findings indicate that prior statin use is related to a decreased risk of worsening clinical outcomes of COVID-19 and length of hospital stay but not to that of SARS-CoV-2 infection.

Statins: Neurobiological underpinnings and mechanisms in mood disorders

Statins (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) treat dyslipidaemia and cardiovascular disease by inhibiting cholesterol biosynthesis. They also have immunomodulatory and anti-inflammatory properties. Beyond cardiovascular disease, cholesterol and inflammation appear to be components of the pathogenesis and pathophysiology of neuropsychiatric disorders. Statins may therefore afford some therapeutic benefit in mood disorders. In this paper, we review the pathophysiology of mood disorders with a focus on pharmacologically relevant pathways, using major depressive disorder and bipolar disorder as exemplars. Statins are discussed in the context of these disorders, with particular focus on the putative mechanisms involved in their anti-inflammatory and immunomodulatory effects. Recent clinical data suggest that statins may have antidepressant properties, however given their interactions with many known biological pathways, it has not been fully elucidated which of these are the major determinants of clinical outcomes in mood disorders. Moreover, it remains unclear what the appropriate dose, or appropriate patient phenotype for adjunctive treatment may be. High quality randomised control trials in concert with complementary biological investigations are needed if the potential clinical effects of statins on mood disorders, as well as their biological correlates, are to be better understood.

Unravelling the mechanisms driving multimorbidity in COPD to develop holistic approaches to patient-centred care

COPD is a major cause of morbidity and mortality worldwide. Multimorbidity is common in COPD patients and a key modifiable factor, which requires timely identification and targeted holistic management strategies to improve outcomes and reduce the burden of disease.We discuss the use of integrative approaches, such as cluster analysis and network-based theory, to understand the common and novel pathobiological mechanisms underlying COPD and comorbid disease, which are likely to be key to informing new management strategies.Furthermore, we discuss the current understanding of mechanistic drivers to multimorbidity in COPD, including hypotheses such as multimorbidity as a result of shared common exposure to noxious stimuli (e.g. tobacco smoke), or as a consequence of loss of function following the development of pulmonary disease. In addition, we explore the links to pulmonary disease processes such as systemic overspill of pulmonary inflammation, immune cell priming within the inflamed COPD lung and targeted messengers such as extracellular vesicles as a result of local damage as a cause for multimorbidity in COPD.Finally, we focus on current and new management strategies which may target these underlying mechanisms, with the aim of holistic, patient-centred treatment rather than single disease management.

The effect of statin therapy on disease-related outcomes in idiopathic pulmonary fibrosis: A systematic review and meta-analysis

BACKGROUND

Idiopathic pulmonary fibrosis is a progressive disease and antifibrotic therapies do not reverse existing fibrosis. There has been emerging evidence of potential role for statins in idiopathic pulmonary fibrosis. The aim of this review is to synthesise the evidence on the efficacy of statins in idiopathic pulmonary fibrosis, focusing on associations with all-cause mortality, disease-specific mortality and change in pulmonary function.

METHODS

Medline and Embase were reviewed to identify relevant publications. Studies were selected if they examined disease-related outcomes including mortality, pulmonary function and adverse events in people with idiopathic pulmonary fibrosis receiving statin therapy.

RESULTS

Five studies with a total of 3407 people with IPF were selected and analysed. The overall risk of bias of five included studies was moderate to serious. In the fixed effect meta-analysis, statin use was associated with a reduction in mortality (RR 0.8; 95% CI 0.72-0.99). However, in the random effects model, there was no longer any significant association between statin use and all-cause mortality (RR 0.87; 95% CI 0.68-1.12). There was no statistically significant association between statin use and decline in FVC % predicted.

CONCLUSION

There is currently insufficient evidence to conclude the effect of statin therapy on disease-related outcomes in idiopathic pulmonary fibrosis. Considering the limitations of available literature, we would recommend a prospective cohort study with capture of dosage and preparation of statin, statin adherence and use of concurrent antifibrotic treatment.

PROSPERO REGISTRATION NUMBER

CRD42019122745.

Chinese Herbs and Repurposing Old Drugs as Therapeutic Agents in the Regulation of Oxidative Stress and Inflammation in Pulmonary Diseases

Several pro-inflammatory factors and proteins have been characterized that are involved in the pathogenesis of inflammatory diseases, including acute respiratory distress syndrome, chronic obstructive pulmonary disease, and asthma, induced by oxidative stress, cytokines, bacterial toxins, and viruses. Reactive oxygen species (ROS) act as secondary messengers and are products of normal cellular metabolism. Under physiological conditions, ROS protect cells against oxidative stress through the maintenance of cellular redox homeostasis, which is important for proliferation, viability, cell activation, and organ function. However, overproduction of ROS is most frequently due to excessive stimulation of either the mitochondrial electron transport chain and xanthine oxidase or reduced nicotinamide adenine dinucleotide phosphate (NADPH) by pro-inflammatory cytokines, such as interleukin-1β and tumor necrosis factor α. NADPH oxidase activation and ROS overproduction could further induce numerous inflammatory target proteins that are potentially mediated via Nox/ROS-related transcription factors triggered by various intracellular signaling pathways. Thus, oxidative stress is considered important in pulmonary inflammatory processes. Previous studies have demonstrated that redox signals can induce pulmonary inflammatory diseases. Thus, therapeutic strategies directly targeting oxidative stress may be effective for pulmonary inflammatory diseases. Therefore, drugs with anti-inflammatory and anti-oxidative properties may be beneficial to these diseases. Recent studies have suggested that traditional Chinese medicines, statins, and peroxisome proliferation-activated receptor agonists could modulate inflammation-related signaling processes and may be beneficial for pulmonary inflammatory diseases. In particular, several herbal medicines have attracted attention for the management of pulmonary inflammatory diseases. Therefore, we reviewed the pharmacological effects of these drugs to dissect how they induce host defense mechanisms against oxidative injury to combat pulmonary inflammation. Moreover, the cytotoxicity of oxidative stress and apoptotic cell death can be protected via the induction of HO-1 by these drugs. The main objective of this review is to focus on Chinese herbs and old drugs to develop anti-inflammatory drugs able to induce HO-1 expression for the management of pulmonary inflammatory diseases.

Association of Statin Use With the In-Hospital Outcomes of 2019-Coronavirus Disease Patients: A Retrospective Study

Background: Statins have multiple protective effects on inflammation, immunity and coagulation, and may help alleviate pneumonia. However, there was no report focusing on the association of statin use with in-hospital outcomes of patients with coronavirus disease 2019 (COVID-19). We investigated the association between the use of statins and in-hospital outcomes of patients with COVID-19.

Methods: In this retrospective case series, consecutive COVID-19 patients admitted at 2 hospitals in Wuhan, China, from March 12, 2020 to April 14, 2020 were analyzed. A 1:1 matched cohort was created by propensity score-matched analysis. Demographic data, laboratory findings, comorbidities, treatments and in-hospital outcomes were collected and compared between COVID-19 patients taking and not taking statins.

Result: A total of 2,147 patients with COVID-19 were enrolled in this study. Of which, 250 patients were on statin therapy. The mortality was 2.4% (6/250) for patients taking statins while 3.7% (70/1,897) for those not taking statins. In the multivariate Cox model, after adjusting for age, gender, admitted hospital, comorbidities, in-hospital medications and blood lipids, the risk was lower for mortality (adjusted HR, 0.428; 95% CI, 0.169–0.907; P = 0.029), acute respiratory distress syndrome (ARDS) (adjusted HR, 0.371; 95% CI, 0.180–0.772; P = 0.008) or intensive care unit (ICU) care (adjusted HR, 0.319; 95% CI, 0.270–0.945; P = 0.032) in the statin group vs. the non-statin group. After propensity score-matched analysis based on 18 potential confounders, a 1:1 matched cohort (206:206) was created. In the matched cohort, the Kaplan-Meier survival curves showed that the use of statins was associated with better survival (P = 0.025). In a Cox regression model, the use of statins was associated with lower risk of mortality (unadjusted HR, 0.254; 95% CI, 0.070–0.926; P = 0.038), development of ARDS (unadjusted HR, 0.240; 95% CI, 0.087–0.657; P = 0.006), and admission of ICU (unadjusted HR, 0.349; 95% CI, 0.150–0.813; P = 0.015). The results remained consistent when being adjusted for age, gender, total cholesterol, triglyceride, low density lipoprotein cholesterol, procalcitonin, and brain natriuretic peptide. The favorable outcomes in statin users remained statistically significant in the first sensitivity analysis with comorbid diabetes being excluded in matching and in the second sensitivity analysis with chronic obstructive pulmonary disease being added in matching.

Conclusion: In this retrospective analysis, the use of statins in COVID-19 patients was associated with better clinical outcomes and is recommended to be continued in patients with COVID-19.

Statins: Could an old friend help in the fight against COVID-19?

The COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has overwhelmed healthcare systems requiring the rapid development of treatments, at least, to reduce COVID-19 severity. Drug repurposing offers a fast track. Here, we discuss the potential beneficial effects of statins in COVID-19 patients based on evidence that they may target virus receptors, replication, degradation, and downstream responses in infected cells, addressing both basic research and epidemiological information. Briefly, statins could modulate virus entry, acting on the SARS-CoV-2 receptors, ACE2 and CD147, and/or lipid rafts engagement. Statins, by inducing autophagy activation, could regulate virus replication or degradation, exerting protective effects. The well-known anti-inflammatory properties of statins, by blocking several molecular mechanisms, including NF-κB and NLRP3 inflammasomes, could limit the "cytokine storm" in severe COVID-19 patients which is linked to fatal outcome. Finally, statin moderation of coagulation response activation may also contribute to improving COVID-19 outcomes. LINKED ARTICLES: This article is part of a themed issue on The Pharmacology of COVID-19. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.21/issuetoc.

Observational studies assessing the pharmacological treatment of obstructive lung disease: strengths, challenges and considerations for study design

Randomised controlled trials (RCTs) are the gold standard for evaluating treatment efficacy in patients with obstructive lung disease. However, due to strict inclusion criteria and the conditions required for ascertaining statistical significance, the patients included typically represent as little as 5% of the general obstructive lung disease population. Thus, studies in broader patient populations are becoming increasingly important. These can be randomised effectiveness trials or observational studies providing data on real-world treatment effectiveness and safety data that complement efficacy RCTs. In this review we describe the features associated with the diagnosis of asthma and chronic obstructive pulmonary disease (COPD) in the real-world clinical practice setting. We also discuss how RCTs and observational studies have reported opposing outcomes with several treatments and inhaler devices due to differences in study design and the variations in patients recruited by different study types. Whilst observational studies are not without weaknesses, we outline recently developed tools for defining markers of quality of observational studies. We also examine how observational studies are capable of providing valuable insights into disease mechanisms and management and how they are a vital component of research into obstructive lung disease. As we move into an era of personalised medicine, recent observational studies, such as the NOVEL observational longiTudinal studY (NOVELTY), have the capacity to provide a greater understanding of the value of a personalised healthcare approach in patients in clinical practice by focussing on standardised outcome measures of patient-reported outcomes, physician assessments, airway physiology, and blood and airway biomarkers across both primary and specialist care.

The potential of Atorvastatin for chronic lung diseases therapy

Atorvastatin (ATO) is of the statin class and is used as an orally administered lipid-lowering drug. ATO is a reversible synthetic competitive inhibitor of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase thus leading to a reduction in cholesterol synthesis. It has recently been demonstrated that ATO has different pharmacological actions, which are unrelated to its lipid-lowering effects and has the ability to treat chronic airway diseases. This paper reviews the potential of ATO as an anti-inflammatory, antioxidant, and anti-proliferative agent after oral or inhaled administration. This paper discusses the advantages and disadvantages of using ATO under conditions associated with those found in the airways. This treatment could potentially be used to support the formulating of ATO as an inhaler for the treatment of chronic respiratory diseases.

Fungal allergen-induced IL-33 secretion involves cholesterol-dependent, VDAC-1-mediated ATP release from the airway epithelium

KEY POINTS

Alternaria aeroallergens induce the release of ATP from human bronchial epithelial (HBE) cells by activating a conductive pathway involving voltage-dependent anion channel-1 (VDAC-1) and by exocytosis of ATP localized within membrane vesicles. Inhibition of VDAC-1 blocked Alternaria-evoked Ca²⁺ uptake across the plasma membrane of HBE cells and interleukin (IL)-33 release into the extracellular media. Reducing cholesterol content with a cholesterol scavenger (β-methylcyclodextrin) or statin compound (simvastatin) blocked ATP and IL-33 release by lowering the expression of VDAC-1 in the plasma membrane. Pretreatment with simvastatin for 24 h also inhibited the increase in tight junction macromolecule permeability that occurs following Alternaria exposure. These results establish a novel role for VDAC-1 as a mechanism underlying ATP release induced by fungal allergens and suggests a possible therapeutic use for cholesterol lowering compounds in reducing Alternaria-stimulated allergic inflammation.

ABSTRACT

Human bronchial epithelial (HBE) cells exposed to allergens derived from the common saprophytic fungus, Alternaria alternata release ATP, which in turn stimulates P2X₇ receptor-mediated Ca²⁺ uptake across the plasma membrane. The subsequent increase in intracellular calcium concentration induces proteolytic processing and secretion of interleukin (IL)-33, a critical cytokine involved in the initiation of allergic airway inflammation. A major objective of the present study was to identify the mechanism responsible for conductive ATP release. The results show that pretreatment of HBE cells with inhibitors of the voltage-dependent anion channel-1 (VDAC-1) or treatment with a VDAC-1 selective blocking antibody or silencing mRNA expression of the channel by RNA interference, inhibit Alternaria-evoked ATP release. Moreover, inhibition of VDAC-1 channel activity or reducing protein expression blocked the secretion of IL-33. Similarly, reducing the cholesterol content of HBE cells with simvastatin or the cholesterol scavenger β-methylcyclodextrin also blocked ATP release and IL-33 secretion by decreasing the level of VDAC-1 expression in the plasma membrane. In addition, simvastatin inhibited the increase in tight junction macromolecule permeability that was previously observed after Alternaria exposure. These results demonstrate a novel function for VDAC-1 as the conductive mechanism responsible for Alternaria-induced ATP release, an essential early step in the processing, mobilization and secretion of IL-33 by the airway epithelium. Furthermore, the simvastatin-evoked reduction of VDAC-1 expression in the plasma membrane, suggests the possibility that cholesterol lowering compounds may be beneficial in alleviating allergic airway inflammation induced by fungal allergens.

Targeting defective pulmonary innate immunity - A new therapeutic option?

Chronic pulmonary conditions now account for 1 in 15 deaths in the US and mortality is increasing. Chronic obstructive pulmonary disease (COPD) is due to become the 3rd largest cause of mortality by 2030 and mortality from other respiratory conditions such as asthma, idiopathic pulmonary fibrosis and cystic fibrosis are not reducing. There is an urgent need for novel therapies to address this problem as many of the current strategies targeting inflammation are not sufficient. The innate immune system of the lung is an important defence against invading pathogens, but in many chronic pulmonary diseases, this system mounts an inappropriate response. In COPD, macrophages are increased in number, but fail to clear pathogens correctly and become highly activated. This leads to increased damage and remodelling of the airways. In idiopathic fibrosis, there is a switch of macrophage phenotype to a cell that promotes abnormal repair. Neutrophils also display dysfunction in COPD where aberrant migratory profiles may lead to increased damage to lung tissue and emphysema; while in cystic fibrosis the proteolytic lung environment damages neutrophil receptors leading to ineffective phagocytosis and migration. Targeting the innate immune system to restore 'normal function' could have enormous benefits. Improving phagocytosis of pathogens could reduce exacerbations and hence the associated decline in lung function, and novel therapeutics such as sulforaphane appear to do this in vitro. Other natural products such as resveratrol and derivatives also have anti-inflammatory properties. Statins have traditionally been used to manage cholesterol levels in hypercholesterolaemia, however these molecules also have beneficial effects on the innate immune cells. Statins have been shown to be anti-inflammatory and restore aberrant neutrophil chemotaxis in aged cells. Other possible agents that may be efficacious are senolytics. These compounds include natural products such as quercetin which have anti-inflammatory properties but can also suppress viral replication. As viruses have been shown to suppress phagocytosis of macrophages, it is possible that these compounds could have benefit during viral exacerbations to protect this innate response. These compounds demonstrate that it is possible to address defective innate responses in the lung but a better understanding of the mechanisms driving defective innate immunity in pulmonary disease may lead to improved therapeutics.

Statin Use and the Risk of Subsequent Hospitalized Exacerbations in COPD Patients with Frequent Exacerbations

Rationale

The potential benefits of statins for the prevention of exacerbations in patients with COPD remains controversial. No previous studies have investigated the impact of statins on clinical outcomes in COPD patients with frequent exacerbations.

Objective

This study aimed to evaluate the association between the use of statins and the risk of subsequent hospitalized exacerbations in COPD frequent exacerbators.

Materials and Methods

We conducted a population-based cohort study using the Taiwan National Health Insurance Research Database. 139,223 COPD patients with a first hospitalized exacerbation between 2004 and 2012 were analyzed. Among them, 35,482 had a second hospitalized exacerbation within a year after the first exacerbation, and were defined as frequent exacerbators. 1:4 propensity score matching was used to create matched samples of statin users and non-users. The competing risk regression analysis model was used to evaluate the association between statin use and exacerbation risk.

Results

The use of statins was associated with a significantly reduced risk in subsequent hospitalized exacerbations in COPD patients after their first hospitalized exacerbation (adjusted subdistribution hazard ration [SHR], 0.89; 95% CI, 0.85-0.93, P<0.001). In frequent exacerbators, the SHR for subsequent hospitalized exacerbations in statins users was 0.88 (95% CI, 0.81-0.94, P=0.001). Subgroup analysis among frequent exacerbators demonstrated that the use of statins only provided a protective effect against subsequent hospitalized exacerbations in male patients aged 75 years and older, with coexisting diabetes mellitus, hypertension or cardiovascular disease, and no protective effect was observed in those with lung cancer or depression. Current use of statins was associated with a greater protective effect for reducing subsequent hospitalized exacerbation.

Conclusion

The use of statins was associated with a significant reduction in the risk of hospitalized exacerbations in COPD patients after a first hospitalized exacerbation and in specified COPD frequent exacerbators.

Lung Macrophage Functional Properties in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is caused by the chronic exposure of the lungs to toxic particles and gases. These exposures initiate a persistent innate and adaptive immune inflammatory response in the airways and lung tissues. Lung macrophages (LMs) are key innate immune effector cells that identify, engulf, and destroy pathogens and process inhaled particles, including cigarette smoke and particulate matter (PM), the main environmental triggers for COPD. The number of LMs in lung tissues and airspaces is increased in COPD, suggesting a potential key role for LMs in initiating and perpetuating the chronic inflammatory response that underpins the progressive nature of COPD. The purpose of this brief review is to discuss the origins of LMs, their functional properties (chemotaxis, recruitment, mediator production, phagocytosis and apoptosis) and changes in these properties due to exposure to cigarette smoke, ambient particulate and pathogens, as well as their persistent altered functional properties in subjects with established COPD. We also explore the potential to therapeutically modulate and restore LMs functional properties, to improve impaired immune system, prevent the progression of lung tissue destruction, and improve both morbidity and mortality related to COPD.

Effect of Atorvastatin on PM10-induced Cytokine Production by Human Alveolar Macrophages and Bronchial Epithelial Cells

Exposure to ambient air pollution particles (PM10) has been associated with increased cardiovascular morbidity and mortality. Inhaled pollutants induce a pulmonary and systemic inflammatory response that is thought to exacerbate cardiovascular disease. The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have been shown to have anti-inflammatory effects that could contribute to their beneficial effect in cardiovascular disease. The aim of this study is to determine the effects of statins on PM10-induced cytokine production in human bronchial epithelial cells (HBECs) and alveolar macrophages (AMs). Primary HBECs and AMs are obtained from resected human lung. Cells are pretreated with different concentrations of atorvastatin for 24 hours and then exposed to 100 μg/mL urban air pollution particles (EHC-93). Cytokine levels (interleukin-1β, interleukin-8, granulocyte-macrophage colonystimulating factor, interleukin-6, and tumor necrosis factor-α) are measured at messenger RNA and protein levels using real-time polymerase chain reaction and bead-based multiplex immunoassay, respectively. PM10 exposure increases production of these cytokines by both cell types. Atorvastatin attenuates PM10-induced messenger RNA expression and cytokine production by AMs but not by HBECs. It is concluded that statins can modulate the PM10-induced inflammatory response in the lung by reducing mediator production by AMs.

Simvastatin Nanoparticles Reduce Inflammation in LPS-Stimulated Alveolar Macrophages

Simvastatin (SV) is widely used as a lipid-lowering medication that has also been found to have beneficial immunomodulatory effects for treatment of chronic lung diseases. Although its anti-inflammatory activity has been investigated, its underlying mechanisms have not yet been clearly elucidated. In this study, the anti-inflammatory and antioxidant effects and mechanism of simvastatin nanoparticles (SV-NPs) on lipopolysaccharide-stimulated alveolar macrophages (AMs) NR8383 cells were investigated. Quantitative cellular uptake of SV-NPs, the production of inflammatory mediators (interleukin-6, tumor necrosis factor, and monocyte chemoattractant protein-1), and oxidative stress (nitric oxide) were tested. Furthermore, the involvement of the nuclear factor κB (NF-κB) signaling pathway in activation of inflammation in AMs and the efficacy of SV were visualized using immunofluorescence. Results indicated that SV-NPs exhibit a potent inhibitory effect on nitric oxide production and secretion of inflammatory cytokine in inflamed AM, without affecting cell viability. The enhanced anti-inflammatory activity of SV-NPs is likely due to SV-improved chemical-physical stability and higher cellular uptake into AM. The study also indicates that SV targets the inflammatory and oxidative response of AM, through inactivation of the NF-κB signaling pathway, supporting the pharmacological basis of SV for treatment of chronic inflammatory lung diseases.

Bronchiectasis and cough: An old relationship in need of renewed attention

Bronchiectasis is an increasingly recognised respiratory condition with limited therapeutic options and a complex spectrum of clinical manifestations that invariably includes chronic cough. As the primary presentation of bronchiectasis in most cases, chronic cough and its mechanistic underpinnings are of central importance but remain poorly understood in this setting. Bronchiectasis is also increasingly identified as an underlying cause of chronic cough highlighting the interrelationship between the two conditions that share overlapping clinical features. Several therapeutic approaches have illustrated positive effects on bronchiectasis-associated cough, however, more focused treatment of heterogeneous cough subtypes may yield better outcomes for patients. A current challenge is the identification of bronchiectasis and cough endophenotypes that may allow improved patient stratification and more targeted therapeutic matching of the right treatment to the right patient. Here we discuss the complex disease phenotypes of bronchiectasis and their interrelationship with cough while considering current and emerging treatment options. We discuss some key cough promoters in bronchiectasis including infection, allergy and immune dysfunction.

Statins and nonalcoholic fatty liver disease in the era of precision medicine: More friends than foes

Nonalcoholic fatty liver disease (NAFLD) describes a spectrum of alcohol-like hepatic histological changes, which occur in the absence of any competing causes of chronic liver disease, notably including significant alcohol consumption. A close and bi-directional relationship links NAFLD with the metabolic syndrome (MetS), and concurrent MetS will hasten the progression to more severe forms of NAFLD, including cirrhosis and hepatocellular carcinoma (HCC). Patients with NAFLD will typically exhibit atherogenic dyslipidemia and increased cardiovascular risk (CVR). Statins are among the most widely prescribed lipid-lowering drugs. Their use has historically been hampered, in individuals with liver disease, owing to the fear of hepatotoxicity. However, studies suggest that statins are not only effective in reducing cardiovascular events, but may also exert multiple beneficial effects on the liver. CVR in those with NAFLD has extensively been covered by our group and others. This updated clinical narrative review will critically examine the effects of statins on the pathogenesis of NAFLD, including the key elementary pathological lesions of NAFLD, i.e. steatosis, inflammation and fibrosis, and its liver-related complications, i.e. cirrhosis, portal hypertension and HCC.

Statins: Old drugs as new therapy for liver diseases?

In addition to lowering cholesterol levels, statins have pleiotropic effects, particularly anti-inflammatory, antiangiogenic, and antifibrotic, that may be beneficial in some chronic inflammatory conditions. Statins have only recently been investigated as a potential treatment option in chronic liver diseases because of concerns related to their safety in patients with impaired liver function. A number of experimental studies in animal models of liver diseases have shown that statins decrease hepatic inflammation, fibrogenesis and portal pressure. In addition, retrospective cohort studies in large populations of patients with cirrhosis and pre-cirrhotic conditions have shown that treatment with statins, with the purpose of decreasing high cholesterol levels, was associated with a reduced risk of disease progression, hepatic decompensation, hepatocellular carcinoma development, and death. These beneficial effects persisted after adjustment for disease severity and other potential confounders. Finally, a few randomised controlled trials have shown that treatment with simvastatin decreases portal pressure (two studies) and mortality (one study). Statin treatment was generally well tolerated but a few patients developed severe side effects, particularly rhabdomyolysis. Despite these promising beneficial effects, further randomised controlled trials in large series of patients with hard clinical endpoints should be performed before statins can be recommended for use in clinical practice.

Statin for Tuberculosis and Pneumonia in Patients with Asthma⁻Chronic Pulmonary Disease Overlap Syndrome: A Time-Dependent Population-Based Cohort Study

We investigated the effects of statins on tuberculosis (TB) and pneumonia risks in asthma⁻chronic pulmonary disease overlap syndrome (ACOS) patients. We extracted data of patients diagnosed as having ACOS during 2000⁻2010 from the Taiwan National Health Insurance Research Database and divided them into statin users and nonusers. All study participants were followed up from the index date until death, withdrawal from insurance, or TB and pneumonia occurred (31 December 2011). The cumulative TB and pneumonia incidence was analyzed using Cox proportional regression analysis with time-dependent variables. After adjustments for multiple confounding factors including age, sex, comorbidities, and use of medications [statins, inhaled corticosteroids (ICSs), or oral steroids (OSs)], statin use was associated with significantly lower TB [adjusted hazard ratio (aHR) 0.49, 95% confidence interval (CI) 0.34⁻0.70] and pneumonia (aHR 0.52, 95% CI 0.41⁻0.65) risks. Moreover, aHRs (95% CIs) for statins combined with ICSs and OSs were respectively 0.60 (0.31⁻1.16) and 0.58 (0.40⁻0.85) for TB and 0.61 (0.39⁻0.95) and 0.57 (0.45⁻0.74) for pneumonia. Thus, statin users had lower TB and pneumonia risks than did nonusers, regardless of age, sex, comorbidities, and ICS or OS use. Pneumonia risk was lower among users of statins combined with ICSs or Oss and TB risk was lower among the users of statins combined with OSs.

Leaky brain in neurological and psychiatric disorders: Drivers and consequences

BACKGROUND

The blood-brain barrier acts as a highly regulated interface; its dysfunction may exacerbate, and perhaps initiate, neurological and neuropsychiatric disorders.

METHODS

In this narrative review, focussing on redox, inflammatory and mitochondrial pathways and their effects on the blood-brain barrier, a model is proposed detailing mechanisms which might explain how increases in blood-brain barrier permeability occur and can be maintained with increasing inflammatory and oxidative and nitrosative stress being the initial drivers.

RESULTS

Peripheral inflammation, which is causatively implicated in the pathogenesis of major psychiatric disorders, is associated with elevated peripheral pro-inflammatory cytokines, which in turn cause increased blood-brain barrier permeability. Reactive oxygen species, such as superoxide radicals and hydrogen peroxide, and reactive nitrogen species, such as nitric oxide and peroxynitrite, play essential roles in normal brain capillary endothelial cell functioning; however, chronically elevated oxidative and nitrosative stress can lead to mitochondrial dysfunction and damage to the blood-brain barrier. Activated microglia, redox control of which is mediated by nitric oxide synthases and nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, secrete neurotoxic molecules such as reactive oxygen species, nitric oxide, prostaglandin, cyclooxygenase-2, quinolinic acid, several chemokines (including monocyte chemoattractant protein-1 [MCP-1], C-X-C motif chemokine ligand 1 [CXCL-1] and macrophage inflammatory protein 1α [MIP-1α]) and the pro-inflammatory cytokines interleukin-6, tumour necrosis factor-α and interleukin-1β, which can exert a detrimental effect on blood-brain barrier integrity and function. Similarly, reactive astrocytes produce neurotoxic molecules such as prostaglandin E2 and pro-inflammatory cytokines, which can cause a 'leaky brain'.

CONCLUSION

Chronic inflammatory and oxidative and nitrosative stress is associated with the development of a 'leaky gut'. The following evidence-based approaches, which address the leaky gut and blood-brain barrier dysfunction, are suggested as potential therapeutic interventions for neurological and neuropsychiatric disorders: melatonin, statins, probiotics containing Bifidobacteria and Lactobacilli, N-acetylcysteine, and prebiotics containing fructo-oligosaccharides and galacto-oligosaccharides.

Challenges in the management of asthma associated with smoking-induced airway diseases

INTRODUCTION

Smoking-induced airway diseases such as chronic bronchitis, emphysema, and small airway dysfunction contribute to the chronic respiratory symptoms experienced by adults with asthma, including those with spirometric chronic obstructive pulmonary disease (COPD), termed asthma-COPD overlap (ACO). Drug treatment of symptomatic smokers with asthma or ACO is uncertain due to their exclusion from most clinical trials.

AREAS COVERED

This review summarizes evidence for the efficacy of small molecule drugs used in the clinic to treat current and former smokers with a diagnostic label of asthma or ACO. Other therapeutic interventions are reviewed, including smoking cessation and biologics.

EXPERT OPINION

Clinical trials and observational studies suggest that smoking cessation and approved drugs used to treat non-smokers with asthma produce clinical benefits in smokers with asthma or ACO, although the overall quality of evidence is low. The efficacy of some treatments for asthma is altered in current smokers, including reduced responsiveness to short-term inhaled corticosteroids and possibly improved responsiveness to leukotriene receptor antagonists. Preliminary findings suggest that low-dose theophylline, statins, and biologics, such as omalizumab, mepolizumab, and dupilumab, may improve clinical outcomes in smokers with asthma or ACO. Improved phenotyping and endotyping of asthma and smoking-induced airway diseases should lead to better targeted therapies.

Role of statins and mevalonate pathway on impaired HDAC2 activity induced by oxidative stress in human airway epithelial cells

In patients with chronic obstructive pulmonary disease (COPD) the inflammatory response is often steroid-resistant, likely since oxidative stress and cigarette smoking impair histone deacetylase 2 (HDAC2) activity. Since it has been demonstrated that statins may restore the HDAC2 activity in cultured human endothelial cells, the aim of this study was to investigate the effects of statins in reversing the steroid-resistance induced by oxidative stress. We evaluated the effects of simvastatin and dexamethasone on HDAC2 expression and activity, and the role of mevalonate and Rho/ROCK pathways in A549 cells, a human lung type II epithelial cell line stressed with H₂O₂. Our results documented that H₂O₂ significantly reduced the HDAC2 expression and activity. In H₂O₂ treated cells dexamethasone was unable to restore the activity of HDAC2, whereas simvastatin restored both the expression and the activity of this enzyme. Our data also showed that mevalonate reduced the activity of HDAC2 whereas Y27632, a Rho/ROCK inhibitor, had no effect on HDAC2 activity when co-administered with simvastatin. Our data suggest that statins could have the potential to restore corticosteroid sensitivity in A549 cells. The evidences of this study suggest that, although both mevalonate and Rho/ROCK pathways are involved in the detrimental effect elicited by oxidative stress, statins may restore the function and expression of depleted HDAC2 via modulating the mevalonate cascade, at least in A549 cells. In conclusion, the modulation of histone acetyltransferase/deacetylase activity may lead to the development of novel anti-inflammatory approaches to inflammatory lung diseases that are currently difficult to treat.

Treatment with Atorvastatin Provides Additional Benefits to Imipenem in a Model of Gram-Negative Pneumonia Induced by Klebsiella pneumoniae in Mice

The clinical pathogen Klebsiella pneumoniae is a relevant cause of nosocomial infections, and resistance to current treatment with carbapenem antibiotics is becoming a significant problem. Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) used for controlling plasma cholesterol levels. There is clinical evidence showing other effects of statins, including decrease of lung inflammation. In the current study, we show that pretreatment with atorvastatin markedly attenuated lung injury, which was correlated with a reduction in the cellular influx into the alveolar space and lungs and downmodulation of the production of proinflammatory mediators in the initial phase of infection in C57BL/6 mice with K. pneumoniae However, atorvastatin did not alter the number of bacteria in the lungs and blood of infected mice, despite decreasing local inflammatory response. Interestingly, mice that received combined treatment with atorvastatin and imipenem displayed better survival than mice treated with vehicle, atorvastatin, or imipenem alone. These findings suggest that atorvastatin could be an adjuvant in host-directed therapies for multidrug-resistant K. pneumoniae, based on its powerful pleiotropic immunomodulatory effects. Together with antimicrobial approaches, combination therapy with anti-inflammatory compounds could improve the efficiency of therapy during acute lung infections.

Serum lipoproteins are not associated with the severity of asthma

BACKGROUND

Asthma is a chronic inflammatory disorder of the bronchi with a complicated and largely unknown pathogenesis. In this context, an emerging role is attributed to the apolipoproteins which serve as structural components of plasma lipoproteins. Low density lipoproteins (LDL) may be involved in the inflammatory pathways of the asthmatic airways; in particular, small dense LDL (sdLDL) particles were associated with increased oxidative susceptibility compared to medium and large sized LDL. In our previous study, we found a positive correlation between forced expiratory volume 1 s (FEV₁) % predicted and larger LDL particles (LDL-1), and an inverse correlation between FEV₁% predicted and sdLDL (LDL-3) in mild, untreated asthmatics. Although LDL appear to be important modulators of inflammation, data on their clinical implications are still lacking.

OBJECTIVE

The aim of the study is to investigate whether LDL subclasses correlate with the severity of asthma, assuming that the atherogenic and most pro-inflammatory LDL contribute to ignite and perpetuate the airway inflammatory processes.

METHODS

The study was conducted in one visit, and included clinical and lung functional assessments, as well as measurements of serum concentrations of the LDL subclasses. Non-denaturing, linear polyacrylamide gel electrophoresis was used to separate and measure LDL subclasses, with the LipoPrint^© System (Quantimetrix Corporation, Redondo Beach, CA, USA). LDL subclasses were distributed as seven bands (LDL-1 to LDL-7), LDL-1 and -2 being defined as large LDL (least pro-inflammatory), and LDL-3 to 7 defined as sdLDL (most pro-inflammatory).

RESULTS

70 asthmatics under inhaled treatment (M/F: 35/35) were enrolled; 10 healthy subjects (M/F: 3/7) served as controls. In the asthmatic group, FEV₁% predicted was 81 ± 22% (mean ± SD), vital capacity (VC) % predicted was 97 ± 18%, and FEV₁/FVC was 0.68 ± 0.1. The mean asthma control test (ACT) score was 18 ± 5. LDL-1 were significantly lower in asthmatics as compared to controls (18 ± 4% vs. 22 ± 4%, p = 0.008). On the contrary, LDL-2 (12 ± 4% vs. 12 ± 5%) and LDL-3 (3 ± 3% vs. 2 ± 2%) were not statistically different between the two groups; smaller subclasses were undetectable. To comply with the design of the study, subjects were classified according to their degree of severity into the 5 Global Initiative for Asthma (GINA) steps: Step 1 (M/F: 4/3, 44 ± 12 yrs), Step 2 (M/F: 1/2, 37 ± 11 yrs), Step 3 (M/F: 12/7, 47 ± 12 yrs), Step 4 (M/F: 8/15, 54 ± 12 yrs), and Step 5 (M/F: 7/9, 56 ± 9 yrs). None of the LDL subclasses showed significant differences between classes of severity: LDL-1 were 16.1 ± 5.6% in Step 1, 18 ± 2.8% in Step 2, 16.7 ± 3.7% in Step 3, 18 ± 3.3% in Step 4, and 19.5 ± 3.2% in Step 5 (p = NS); LDL2 were 14 ± 3.6%, 15 ± 3.4%, 12.4 ± 5.3%, 12.7 ± 4.4% and 11.3 ± 4.2%, respectively (p = NS); LDL3 were 5 ± 5.2%, 4.4 ± 2.6%, 3.3 ± 3.6%, 3.2 ± 2.6% and 2.4 ± 1.8%, p = NS. Finally, no relationship was detected between LDL subclasses and lung function parameters as well as the ACT scores.

CONCLUSIONS

The current findings confirm a role of LDL as a potential biomarker in the diagnostic process for asthma, and suggest that LDL cannot be used as marker of severity of the disease.

Statins in the treatment of COPD and asthma-where do we stand?

Asthma and chronic obstructive pulmonary disease (COPD) are the two most prevalent obstructive lung diseases that account for tremendous morbidity and mortality throughout the world. These diseases have strong inflammatory components, with multiple prior studies showing elevated levels of various inflammatory markers and cells in those with COPD and asthma. Therefore, efforts to target inflammation in management of these diseases are of great interest. Statins, which define a class of drugs that are HMG-CoA inhibitors, are used to decrease cholesterol levels and have also been described to have many pleotropic effects that include anti-inflammatory and anti-oxidative properties. These properties have led to multiple studies looking at the potential use of statins in decreasing inflammation in many diseases, including COPD and asthma. This review aims to address the current evidence behind the potential use of statins in the treatment of asthma and COPD.

Simvastatin Therapy and Bronchoalveolar Lavage Fluid Biomarkers in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a progressive disease underlain by airway inflammation. Despite trials with new generations of anti-inflammatory drugs to alleviate the disease burden, the effective curative treatment remains elusive. In this context, the aim of this study was to assess the influence of simvastatin, a leading member of the family of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, known to display anti-inflammatory and immunomodulatory activity, on symptoms and lung function, as well as the proportion of inflammatory cells, cytokines, proteolytic enzymes, and surfactant protein D (SP-D) content in bronchoalveolar lavage fluid (BALF) in COPD patients. There were 50 patients with moderate-to-severe airway obstructions included into the study, subdivided into simvastatin-treated (Zocor - MSD; 40 mg daily) and control simvastatin-untreated groups, other treatment being equal. Pulmonary functions tests and bronchofiberoscopy with BALF procedure were performed before and after 3-month-long treatment in both groups. The major finding was that simvastatin treatment caused a distinct increase in the airway content of SP-D. Further effects, albeit smaller in magnitude, consisted of reductions in the proportion of airway neutrophils and in MMP-9 content, all with a benefit of improved score in the disease activity assessment test. There were no appreciable changes noted in lung function or dyspnea perception, which could be ascribed to simvastatin treatment. We conclude that statin's anti-inflammatory and surfactant homeostasis preserving properties may offer promise as an adjunctive treatment in COPD patients. The SP-D content in BALF has a potential to become a marker of COPD inflammatory activity and treatment monitoring.

Inhaled simvastatin nanoparticles for inflammatory lung disease

Aim: Current inhaled treatments are not adequate to treat all lung diseases. In this study, a promising nanotechnology has been developed to deliver a potential anti-inflammatory and muco-inhibitory compound, simvastatin, for treatment of inflammatory lung diseases via inhalation. Materials & methods: Simvastatin nanoparticles (SV-NPs) encapsulated with poly(lactic-co-glycolic) acid were fabricated using the solvent and anti-solvent precipitation method. Results: SV-NPs were found to be stable up to 9 months at 4°C in a freeze-dried form prior to reconstitution. The amount of mucus produced was significantly reduced after SV-NPs treatment on inflammation epithelial cell models and were effective in suppressing the proinflammatory marker expression. Conclusion: This study suggests that SV-NPs nebulization could potentially be used for the treatment of chronic pulmonary diseases.

Lack of Association between Preoperative Statin Use and Respiratory and Neurologic Complications after Cardiac Surgery

Background

Statins may reduce the risk of pulmonary and neurologic complications after cardiac surgery.

Methods

The authors acquired data for adults who had coronary artery bypass graft, valve surgery, or combined procedures. The authors matched patients who took statins preoperatively to patients who did not. First, the authors assessed the association between preoperative statin use and the primary outcomes of prolonged ventilation (more than 24 h), pneumonia (positive cultures of sputum, transtracheal fluid, bronchial washings, and/or clinical findings consistent with the diagnosis of pneumonia), and in-hospital all-cause mortality, using logistic regressions. Second, the authors analyzed the collapsed composite of neurologic complications using logistic regression. Intensive care unit and hospital length of stay were evaluated with Cox proportional hazard models.

Results

Among 14,129 eligible patients, 6,642 patients were successfully matched. There was no significant association between preoperative statin use and prolonged ventilation (statin: 408/3,321 [12.3%] vs. nonstatin: 389/3,321 [11.7%]), pneumonia (44/3,321 [1.3%] vs. 54/3,321 [1.6%]), and in-hospital mortality (52/3,321 [1.6%] vs. 43/3,321 [1.3%]). The estimated odds ratio was 1.06 (98.3% CI, 0.88 to 1.27) for prolonged ventilation, 0.81 (0.50 to 1.32) for pneumonia, and 1.21 (0.74 to 1.99) for in-hospital mortality. Neurologic outcomes were not associated with preoperative statin use (53/3,321 [1.6%] vs. 56/3,321 [1.7%]), with an odds ratio of 0.95 (0.60 to 1.50). The length of intensive care unit and hospital stay was also not associated with preoperative statin use, with a hazard ratio of 1.04 (0.98 to 1.10) for length of hospital stay and 1.00 (0.94 to 1.06) for length of intensive care unit stay.

Conclusions

Preoperative statin use did not reduce pulmonary or neurologic complications after cardiac surgery.

Effect of simvastatin on MMPs and TIMPs in cigarette smoke-induced rat COPD model

BACKGROUND

Proteases may play an important role in the development of chronic obstructive pulmonary disease and emphysema in response to cigarette smoke exposure (CSE). The current study was designed to investigate the expression of matrix metalloproteinase (MMP)-8, MMP-9, MMP-12, tissue inhibitor of MMP (TIMP)-1, and TIMP-4 in rat lung tissues in response to CSE, and assessed the effect of simvastatin in regulating expression of MMPs and TIMPs.

METHODS

Thirty normal Sprague Dawley (SD) rats were divided into control (n=10), CSE (n=10), and CSE plus simvastatin (n=10) groups. Animals were whole-body exposed to the cigarette smoke in the box for 1 hour each time, twice a day, 5 days a week for 16 weeks. Animals of CSE + simvastatin group were intra-gastrically administered simvastatin at a dose of 5 mg/kg/day followed by CSE. Bronchoalveolar lavage fluid was harvested for inflammatory cell count and lung tissues were stained for morphologic examination. Expression of mRNA and protein level of MMP-8, MMP-9, MMP-12, TIMP-1, and TIMP-4 was assessed by real-time reverse transcription polymerase chain reaction and immunohistochemistry, respectively.

RESULTS

CSE resulted in a significant increase of mean linear intercept (MLI: 34.6±2.0 μm) and bronchial wall thickness and diameter (BWT/D, 0.250±0.062) compared to control (MLI: 24.0±1.7 μm, BWT/D: 0.160±0.034, P<0.01). In contrast, mean alveolar number was significantly decreased in the CSE group than that in the control group (13.5±2.0 of CSE vs 21.5±2.0 N/μm2 of control, P>0.01). Simvastatin slightly but not significantly prevented alteration of MLI, BWT/D, and mean alveolar number (MLI: 33.4±1.4 μm; BWT/D: 0.220±0.052; mean alveolar number: 15.5±2.5 N/μm2, P>0.05). Total white blood cell was significantly increased in the bronchoalveolar lavage fluid of smoking group (3.3±2.5×109 cells/L vs 1.1±1.3×109 cells/L of control, P<0.01), and it was significantly reduced by simvastatin (2.3±2.1×109 cells/L, P<0.01). CSE resulted in significantly increased accumulation of neutrophils and macrophages (neutrophils: 14.5%±1.3% of CSE group vs 9.1%±1.5% of control; macrophage: 91%±3% of CSE group vs 87%±2% of control, P<0.05), and simvastatin significantly reduced neutrophils (12.9%±2.0%, P<0.05) in the bronchoalveolar lavage fluid, but had no effect on macrophage (89%±1.6%, P>0.05). In response to CSE, MMP-8, MMP-9, and MMP-12 mRNA were upregulated more than sevenfold, while TIMP-1 and TIMP-4 increased two- to fivefold. Simvastatin significantly blocked upregulation of MMP-8 and -9 (P<0.01), but had no effect on MMP-12, TIMP-1 and TIMP-4 mRNA (P>0.05). In addition, simvastatin significantly blocked cigarette smoke-induced MMP-8 and -9 protein synthesis, while it had no significant effect on TIMP-1 and -4 protein synthesis even in the presence of cigarette smoke.

CONCLUSION

CSE resulted in imbalance of MMPs and TIMPs, and by which mechanism, cigarette smoke may lead to insufficient lung tissue repair. Simvastatin partially blocked airway inflammation and MMP production and, thus, statins may modulate composition of the lung extracellular matrix.

New and developing non-adrenoreceptor small molecule drugs for the treatment of asthma

INTRODUCTION

Inhaled corticosteroids (ICS) alone or in combination with an inhaled long-acting beta₂-agonist (LABA) are the preferred long-term treatment for adults and adolescents with symptomatic asthma. Additional drugs include leukotriene-receptor antagonists, slow-release theophylline and the long-acting muscarinic antagonist (LAMA) tiotropium (approved in 2015). There is a need for more effective therapies, as many patients continue to have poorly controlled asthma. Areas covered: New and developing long-acting non-adrenoreceptor synthetic drugs for the treatment of symptomatic chronic asthma despite treatment with an ICS alone or combined with a LABA. Data was reviewed from studies published up until November 2016. Expert opinion: Tiotropium improves lung function and has a modest effect in reducing exacerbations when added to ICS alone or ICS and LABA. The LAMAs umeclidinium and glycopyrronium are under development in fixed dose combination with ICS and LABA. Novel small molecule drugs, such as CRTH2 receptor antagonists, PDE₄ inhibitors, protein kinase inhibitors and nonsteroidal glucocorticoid receptor agonists and 'off-label' use of licensed drugs, such as macrolides and statins are under investigation for asthma, although their effectiveness in clinical practice is not established. To better achieve the goal of developing effective novel small molecule drugs for asthma will require greater understanding of mechanisms of disease and the different phenotypes and endotypes of asthma.

Roles of the Mevalonate Pathway and Cholesterol Trafficking in Pulmonary Host Defense

The mevalonic acid synthesis pathway, cholesterol, and lipoproteins play fundamental roles in lung physiology and the innate immune response. Recent literature investigating roles for cholesterol synthesis and trafficking in host defense against respiratory infection was critically reviewed. The innate immune response and the cholesterol biosynthesis/trafficking network regulate one another, with important implications for pathogen invasion and host defense in the lung. The activation of pathogen recognition receptors and downstream cellular host defense functions are critically sensitive to cellular cholesterol. Conversely, microorganisms can co-opt the sterol/lipoprotein network in order to facilitate replication and evade immunity. Emerging literature suggests the potential for harnessing these insights towards therapeutic development. Given that >50% of adults in the U.S. have serum cholesterol abnormalities and pneumonia remains a leading cause of death, the potential impact of cholesterol on pulmonary host defense is of tremendous public health significance and warrants further mechanistic and translational investigation.

Bronchiectasis in the Last Five Years: New Developments

Bronchiectasis, a chronic lung disease characterised by cough and purulent sputum, recurrent infections, and airway damage, is associated with considerable morbidity and mortality. To date, treatment options have been limited to physiotherapy to clear sputum and antibiotics to treat acute infections. Over the last decade, there has been significant progress in understanding the epidemiology, pathophysiology, and microbiology of this disorder. Over the last five years, methods of assessing severity have been developed, the role of macrolide antibiotic therapy in reducing exacerbations cemented, and inhaled antibiotic therapies show promise in the treatment of chronic Pseudomonas aeruginosa infection. Novel therapies are currently undergoing Phase 1 and 2 trials. This review aims to address the major developments within the field of bronchiectasis over this time.