Chronic obstructive pulmonary disease: patho-physiology, current methods of treatment and the potential for simvastatin in disease management

Guggulsterone protects against cigarette smoke-induced COPD linked lung inflammation

Recently, we have shown that guggulsterone is the principal constituent responsible for protective effects of Commiphora wightii against elastase-induced chronic obstructive pulmonary disease (COPD)-linked inflammation/emphysema. Given that cigarette smoke (CS) exposure is a primary risk factor for COPD and beneficial effects of guggulsterone have not been investigated in CS-induced COPD-linked lung inflammation. The present work was designed to validate the potential of guggulsterone in amelioration of COPD-linked lung inflammation by using a CS-based mouse model of the condition. Male BALB/c mice were exposed to 9 cigarettes/day with 1 h interval for 4 days daily. Guggulsterone was administered daily at a dose of 10 mg/kg orally for 4 consecutive days, 1 h before initiation of CS exposure. Mice were subjected to measurement of lung function followed by procurement of bronchoalveolar lavage fluid (BALF)/lung tissue. BALF was analyzed for inflammatory cells and pro-inflammatory cytokines. Lung tissue was subjected to RT-PCR for gene expression analysis. Data showed that CS exposure resulted in a significant increase in total BALF cells, predominantly neutrophils, and macrophages. Interestingly, guggulsterone administration significantly blunted CS-induced inflammation as reflected by reduced neutrophil and macrophage count. Further, the compound inhibited CS-induced gene expression of pro-inflammatory mediators TNF-α/ IL-1β/ G-CSF/and KC in lungs along with the production of pro-inflammatory mediators TNF-α/ IL-1β/ IL-6/ G-CSF/ KC/and MCP-1 in BALF. Further, guggulsterone improved the lung function parameters upon CS exposure. Analysis of mRNA expression of matrix metalloproteinase (MMP)-9 and tissue inhibitor of matrix metalloproteinase (TIMP)-1 suggests that guggulsterone may restore the fine balance between matrix-degrading proteases and its inhibitor in lung tissue upon CS exposure, which may contribute in the development of emphysema at later stages. Overall, our data show that guggulsterone protects against CS-induced COPD-linked lung inflammation by modulating relevant molecular players. Based on the potential effects of guggulsterone in the amelioration of CS-induced lung inflammation, we speculate that guggulsterone might alter chronic CS-induced emphysema.

Antioxidant Effects of Statins by Modulating Nrf2 and Nrf2/HO-1 Signaling in Different Diseases

Statins are competitive inhibitors of hydroxymethylglutaryl-CoA (HMG-CoA) reductase and have been used to treat elevated low-density lipoprotein cholesterol (LDL-C) for almost four decades. Antioxidant and anti-inflammatory properties which are independent of the lipid-lowering effects of statins, i.e., their pleiotropic effects, might be beneficial in the prevention or treatment of many diseases. This review discusses the antioxidant effects of statins achieved by modulating the nuclear factor erythroid 2 related factor 2/ heme oxygenase-1 (Nrf2/HO-1) pathway in different organs and diseases. Nrf2 and other proteins involved in the Nrf2/HO-1 signaling pathway have a crucial role in cellular responses to oxidative stress, which is a risk factor for ASCVD. Statins can significantly increase the DNA-binding activity of Nrf2 and induce the expression of its target genes, such as HO-1 and glutathione peroxidase) GPx, (thus protecting the cells against oxidative stress. Antioxidant and anti-inflammatory properties of statins, which are independent of their lipid-lowering effects, could be partly explained by the modulation of the Nrf2/HO-1 pathway.

Development of polymer-based nanoparticles for zileuton delivery to the lung: PMeOx and PMeOzi surface chemistry reduces interactions with mucins

In this paper, two amphiphilic graft copolymers were synthesized by grafting polylactic acid (PLA) as hydrophobic chain and poly(2-methyl-2-oxazoline) (PMeOx) or poly(2-methyl-2-oxazine) (PMeOzi) as hydrophilic chain, respectively, to a backbone of α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA). These original graft copolymers were used to prepare nanoparticles delivering Zileuton in inhalation therapy. Among various tested methods, direct nanoprecipitation proved to be the best technique to prepare nanoparticles with the smallest dimensions, the narrowest dimensional distribution and a spherical shape. To overcome the size limitations for administration by inhalation, the nano-into-micro strategy was applied, encapsulating the nanoparticles in water-soluble mannitol-based microparticles by spray-drying. This process has allowed to produce spherical microparticles with the proper size for optimal lung deposition, and, once in contact with fluids mimicking the lung district, able to dissolve and release non-aggregated nanoparticles, potentially able to spread through the mucus, releasing about 70% of the drug payload in 24 h.

Air-liquid interface cultures of the healthy and diseased human respiratory tract: promises, challenges and future directions

Air-liquid interface (ALI) culture models currently represent a valid instrument to recreate the typical aspects of the respiratory tract in vitro in both healthy and diseased state. They can help reducing the number of animal experiments, therefore, supporting the 3R principle. This review discusses ALI cultures and co-cultures derived from immortalized as well as primary cells, which are used to study the most common disorders of the respiratory tract, in terms of both pathophysiology and drug screening. The article displays ALI models used to simulate inflammatory lung diseases such as chronic obstructive pulmonary disease (COPD), asthma, cystic fibrosis, lung cancer, and viral infections. It also includes a focus on ALI cultures described in literature studying respiratory viruses such as SARS-CoV-2 causing the global Covid-19 pandemic at the time of writing this review. Additionally, commercially available models of ALI cultures are presented. Ultimately, the aim of this review is to provide a detailed overview of ALI models currently available and to critically discuss them in the context of the most prevalent diseases of the respiratory tract.

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.

Clinical Effectiveness of a Combination of Black Elder Berries, Violet Herb, and Calendula Flowers in Chronic Obstructive Pulmonary Disease: The Results of a Double-Blinded Placebo-Controlled Study

Chronic obstructive pulmonary disease (COPD) is a multifactorial disease, in which systemic inflammation plays a key role. This 6-month randomized double-blinded placebo-controlled study evaluates the possible effect of natural preparation Inflaminat on clinical symptoms of COPD, indicators of respiratory function, and exacerbation frequency in 60 patients with moderate severity of COPD. Inflaminat is a combination of natural ingredients black elder (Sambucus nigra L.) berries, violet (Viola tricolor L.) herb, and calendula (Calendula officinalis L.) flowers. The preparation has been previously demonstrated to possess anticytokine and anti-inflammatory effects in experimental studies. In present study, COPD dynamics were evaluated by means of BCSS (Breathlessness, Cough, and Sputum Scale) and spirometry tests. It was shown that 6-months Inflaminat administration led to significant decrease of BCSS points from 3.0 ± 0.6 to 1.9 ± 0.7, (p = 0.002) as well as significant increase of FEV1 from 66 ± 18% to 73 ± 17%, (p = 0.042); there were no beneficial dynamics in placebo group. Side effects associated with preparation administration were not identified. The results of the study suggest that Inflaminat may be employed in treatment of patients with moderate severity of COPD, since it has a positive effect on COPD symptoms according BCSS and indicators of respiratory function FEV1.

Difluoromethylation of Phenols and Thiophenols with the S-(Difluo-romethyl)sulfonium Salt: Reaction, Scope, and Mechanistic Study

A facile and practical approach for the difluoromethylation of phenols and thiophenols was described. Making use of the recently developed bench-stable S-(difluoromethyl)sulfonium salt as the difluorocarbene precursor, a wide variety of diversely functionalized phenols and thiophenols were readily converted to their corresponding aryl difluoromethyl ethers in good to excellent yields in the presence of lithium hydroxide. Chemoselectivity of various O,S-nucleophiles toward difluorocarbene was systematically studied, suggesting the reactivity order ArS- > RS-, ArO- > ROH > RO-, ArSH, ArOH, RSH.

Mevalonate signaling, COPD and cancer: the statins and beyond

Evidence suggests that smoking confers a persistent and/or exaggerated inflammatory response in the lungs that, with underlying genetic susceptibility, may result in lung remodeling and impaired repair. The innate immune response to smoking described above, which is modified by the mevalonate pathway, provides a plausible pathogenic link between the development of chronic obstructive pulmonary disease and lung cancer. The mevalonate pathway modifies innate responsiveness through important intracellular signaling molecules called guanine phosphate transferases (GTPases) such as Rho-A. Smoke exposure activates cell surface proteins which, through the mediating influence of GTPases, then modifies the activation of nuclear factor kappa -light-chain-enhancer of activated B cells (NFĸB) its downstream effects on genes underlying innate immunity, neutrophilic inflammation and carcinogenesis. The mevalonate pathway is modifiable through the enzyme 3-hydroxy-3-methyl-glutaryl-Coenzyme A (HMGCo-A) reductase. This enzyme controls the rate limiting step of the mevalonate pathway and is subject to inhibition by statin drugs (HMGCo-A reductase inhibitors) and small chain fatty acids derived from high dietary fiber intake. Ths, inhibitory effect dampens the innate immune response to smoking and may modify pulmonary inflammation and lung remodeling. This article is a symposia summary outlining the preclinical and clinical data suggesting that statins and a high-fiber diet may have a chemopreventive effect on lung cancer.

Effectiveness of long-term using statins in COPD - a network meta-analysis

OBJECTIVES

To evaluate the effectiveness of long-term treatment of statins for chronic obstructive pulmonary disease (COPD), and to answer which one is better.

METHODS

General meta-analysis was performed to produce polled estimates of the effect of mortality, inflammatory factors, and lung function index in COPD patients by the search of PubMed, Web of Science, Embase, and China National Knowledge Infrastructure for eligible studies. A network meta-analysis was performed to synthetically compare the effectiveness of using different statins in COPD patients.

RESULTS

General meta-analysis showed that using statins reduced the risk of all-cause mortality, heart disease-related mortality and COPD acute exacerbation (AECOPD) in COPD patients, the RR (95% CI) were 0.72 (0.63,0.84), 0.72 (0.53,0.98) and 0.84 (0.79,0.89), respectively. And using statins reduced C-reactive protein (CRP) and pulmonary hypertension (PH) in COPD patients, the SMD (95% CI) were - 0.62 (- 0.52,-0.72) and - 0.71 (- 0.85,-0.57), respectively. Network meta-analysis showed that Fluvastatin (97.7%), Atorvastatin (68.0%) and Rosuvastatin (49.3%) had higher cumulative probability than other statins in reducing CRP in COPD patients. Fluvastatin (76.0%) and Atorvastatin (75.4%) had higher cumulative probability than other satins in reducing PH in COPD patients.

CONCLUSIONS

Using statins can reduce the risk of mortality, the level of CRP and PH in COPD patients. In addition, Fluvastatin and Atorvastatin are more effective in reducing CRP and PH in COPD patients.

Repurposing of statins via inhalation to treat lung inflammatory conditions

Despite many therapeutic advancements over the past decade, the continued rise in chronic inflammatory lung diseases incidence has driven the need to identify and develop new therapeutic strategies, with superior efficacy to treat these diseases. Statins are one class of drug that could potentially be repurposed as an alternative treatment for chronic lung diseases. They are currently used to treat hypercholesterolemia by inhibiting the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, that catalyses the rate limiting step in the mevalonate biosynthesis pathway, a key intermediate in cholesterol metabolism. Recent research has identified statins to have other protective pleiotropic properties including anti-inflammatory, anti-oxidant, muco-inhibitory effects that may be beneficial for the treatment of chronic inflammatory lung diseases. However, clinical studies have yielded conflicting results. This review will summarise some of the current evidences for statins pleiotropic effects that could be applied for the treatment of chronic inflammatory lung diseases, their mechanisms of actions, and the potential to repurpose statins as an inhaled therapy, including a detailed discussion on their different physical-chemical properties and how these characteristics could ultimately affect treatment efficacies. The repurposing of statins from conventional anti-cholesterol oral therapy to inhaled anti-inflammatory formulation is promising, as it provides direct delivery to the airways, reduced risk of side effects, increased bioavailability and tailored physical-chemical properties for enhanced efficacy.

Drug delivery to the brain: how can nanoencapsulated statins be used in the clinic?

Statins are used for the primary and secondary prevention of cardiovascular disease by inhibiting cholesterol synthesis in the liver. Statins have also noncholesterol-related effects, called pleiotropic effects, which arise from statins' anti-inflammatory, immunomodulatory and antioxidant properties. These effects are especially attractive for the treatment of various brain diseases ranging from stroke to neurodegenerative diseases. Still, low brain concentrations after oral drug administration hinder the clinical application of statins in these pathologies. Pharmaceutical nanotechnologies may offer a solution to this problem, as local or targeted delivery of nanoencapsulated statins may increase brain availability. This special report rapidly summarizes the potential of statins in the treatment of brain diseases and the pharmaceutical nanotechnologies that could provide a viable approach to enable these indications.

Genetic polymorphisms of IL17A, TLR4 and P2RX7 and associations with the risk of chronic obstructive pulmonary disease

We investigated the association between genetic polymorphisms of IL17A, TLR4 and P2RX7 genes and chronic obstructive pulmonary disease (COPD) in a Han population. We performed a case-control study with 152 COPD subjects from the Third People's Hospital of Nantong in 2015. Healthy controls were selected from a group of people attending the physical examination and were frequency-matched to the cases by sex and age. Genotyping was performed using TaqMan allelic discrimination technology. A logistic regression model was used to calculated odds ratios (OR) and 95% confidence intervals (CI). After Bonferroni correction, polymorphisms rs2275913 and rs763780 in the IL17A gene, rs10759932 and rs2737190 in the TLR4 gene, and rs1718119 in the P2RX7 gene were significantly associated with altered risk for COPD. Individuals carrying rs2275913 allele A had a reduced risk (OR 0.62; 95% CI: 0.46-0.86). Individuals carrying rs763780 allele C had an increased risk (OR 1.96; 95% CI: 1.29-2.98). Individuals carrying rs10759932 allele C had a reduced risk (OR 0.49; 95% CI: 0.34-0.73). Individuals carrying rs2737190 allele G had a reduced risk (OR 0.51; 95% CI: 0.37-0.71). Individuals carrying rs1718119 allele A had a reduced risk (OR 0.69; 95% CI: 0.45-1.06).Genetic polymorphisms in IL17A, TLR4 and P2RX7 genes were significantly associated with altered risks for COPD.

Statins reduce all-cause mortality in chronic obstructive pulmonary disease: an updated systematic review and meta-analysis of observational studies

Recently, a number of observational studies have suggested that use of statins reduces mortality in patients suffering from chronic obstructive pulmonary disease (COPD). To obtain a more valid assessment, we update the meta-analysis of the effect of statins on COPD exacerbation and mortality. We searched for eligible articles using PubMed, Medline, Embase, the Cochrane Central Register of Controlled Trials, Cochrane Databases and Web of Science between January 2006 and February 2017, with no restrictions. The hazard ratio (HR) with 95% confidence interval (CI) was estimated. Publication bias was evaluated by funnel plot and Begg's test. Sensitivity analyses were also conducted. Twenty studies with a total of 303,981 patients were included. Thirteen articles provided data on all-cause mortality (165,221 participants), and the pooled hazard ratio of 0.65 (95% CI: 0.57–0.74, P < 0.001). Nine cohorts involving 155,435 patients reported data for COPD exacerbation with or without hospitalization, and they gave a HR of 0.58(95%CI: 0.48–0.72, P < 0.001). Our systematic review of exclusively observational studies showed a clear benefit of statins for patients suffering from COPD.

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.

The nasal delivery of nanoencapsulated statins - an approach for brain delivery

Purpose

Along with their cholesterol-lowering effect, statins have shown a wide range of pleiotropic effects potentially beneficial to neurodegenerative diseases. However, such effects are extremely elusive via the conventional oral administration. The purpose of the present study was to prepare and characterize the physicochemical properties and the in vivo biodistribution of simvastatin-loaded lecithin/chitosan nanoparticles (SVT-LCNs) suitable for nasal administration in view of an improved delivery of the statins to the brain.

Materials and methods

Chitosan, lecithin, and different oil excipients were used to prepare nanocapsules loaded with simvastatin. Particle size distribution, surface charge, structure, simvastatin loading and release, and interaction with mucus of nanoparticles were determined. The nanoparticle nasal toxicity was evaluated in vitro using RPMI 2651 nasal cell lines. Finally, in vivo biodistribution was assessed by gamma scintigraphy via Tc99m labeling of the particles.

Results

Among the different types of nanoparticles produced, the SVT-LCN_MaiLab showed the most ideal physicochemical characteristics, with small diameter (200 nm), positive surface charge (+48 mV) and high encapsulation efficiency (EE; 98%). Size distribution was further confirmed by nanoparticle tracking analysis and electron microscopy. The particles showed a relatively fast release of simvastatin in vitro (35.6%±4.2% in 6 hours) in simulated nasal fluid. Blank nanoparticles did not show cytotoxicity, evidencing that the formulation is safe for nasal administration, while cytotoxicity of simvastatin-loaded nanoparticles (IC₅₀) was found to be three times lower than the drug solution (9.92 vs 3.50 μM). In rats, a significantly higher radioactivity was evidenced in the brain after nasal delivery of simvastatin-loaded nanoparticles in comparison to the administration of a similar dose of simvastatin suspension.

Conclusion

The SVT-LCNs developed presented some of the most desirable characteristics for mucosal delivery, that is, small particle size, positive surface charge, long-term stability, high EE, and mucoadhesion. In addition, they displayed two exciting features: First was their biodegradability by enzymes present in the mucus layer, such as lysozyme. This indicates a new Trojan-horse strategy which may enhance drug release in the proximity of the nasal mucosa. Second was their ability to enhance the nose-to-brain transport as evidenced by preliminary gamma scintigraphy studies.

Simvastatin requires activation in accessory cells to modulate T-cell responses in asthma and COPD

T-cell-dependent airway and systemic inflammation triggers the progression of chronic obstructive pulmonary disease (COPD) and asthma. Retrospective studies suggest that simvastatin has anti-inflammatory effects in both diseases but it is unclear, which cell types are targeted. We hypothesized that simvastatin modulates T-cell activity. Circulating CD4+ and CD8+ T-cells, either pure, co-cultured with monocytes or alveolar macrophages (AM) or in peripheral blood mononuclear cells (PBMCs), were ex vivo activated towards Th1/Tc1 or Th2/Tc2 and incubated with simvastatin. Markers for Th1/Tc1 (IFNγ) and Th2/Tc2 (IL-5, IL-13) were measured by ELISA; with PBMCs this was done comparative between 11 healthy never-smokers, 11 current smokers without airflow limitation, 14 smokers with COPD and 11 never-smokers with atopic asthma. T-cell activation induced IFNγ, IL-5 and IL-13 in the presence and absence of accessory cells. Simvastatin did not modulate cytokine expression in pure T-cell fractions. β-hydroxy-simvastatin acid (activated simvastatin) suppressed IL-5 and IL-13 in pure Th2- and Tc2-cells. Simvastatin suppressed IL-5 and IL-13 in Th2-cells co-cultivated with monocytes or AM, which was partially reversed by the carboxylesterase inhibitor benzil. Simvastatin suppressed IL-5 production of Th2/Tc2-cells in PBMCs without differences between cohorts and IL-13 stronger in never-smokers and asthma compared to COPD. Simvastatin induced IFNγ in Th1/Tc1-cells in PBMCs of all cohorts except asthmatics. Simvastatin requires activation in accessory cells likely by carboxylesterase to suppress IL-5 and IL-13 in Th2/Tc2-cells. The effects on Il-13 are partially reduced in COPD. Asthma pathogenesis prevents simvastatin-induced IFNγ up-regulation. Simvastatin has anti-inflammatory effects that could be of interest for asthma therapy.

Could simvastatin be considered as a potential therapy for chronic lung diseases? A debate on the pros and cons

INTRODUCTION

Simvastatin (SV) is a drug from the statin class, currently used orally as an anti-cholesterolemic drug. It inhibits the 3-hydroxy-3-methyl-glutaryl-Coenzyme A (HMG-CoA) reductase to reduce cholesterol synthesis. Recently, it has been found that SV also has several other protective pharmacological actions unrelated to its anti-cholesterol effects that might be beneficial in the treatment of chronic airway diseases.

AREAS COVERED

This review summarizes the evidence relating to SV as a potential anti-inflammatory, anti-oxidant and muco-inhibitory agent, administered both orally and via pulmonary inhalation, and discusses its pro and cons. Evidence could potentially be used to support the delivery of SV as inhaled formulation for the treatment of chronic respiratory diseases.

EXPERT OPINION

The use of SV as anti-inflammatory, anti-oxidant and muco-inhibitory agent for drug delivery to the lung is promising. Inhaled SV formulations could allow the delivery profile to be customized and optimized to take advantage of the rapid onset of action, low systemic side effect and improved physico-chemical stability. This treatment could potentially to be used clinically for the localized treatment of lung diseases where inflammation and oxidative stress production is present.

Statin Effects on Exacerbation Rates, Mortality, and Inflammatory Markers in Patients with Chronic Obstructive Pulmonary Disease: A Review of Prospective Studies

Chronic obstructive pulmonary disease (COPD) is a debilitating, irreversible disease with currently available therapies targeting symptom control and exacerbation reduction. A need for alternative disease-modifying therapies remains, specifically those that may have antiinflammatory and immunomodulatory properties that impact the pathophysiologic components of COPD. Statin drugs, the current gold standard for the treatment of dyslipidemia and prevention of cardiovascular disease (CVD), contain properties that affect the inflammatory disease processes seen in COPD. Several retrospective studies have demonstrated that statins may have a benefit in the reduction of morbidity and mortality in patients with COPD. This has led to prospective trials evaluating the impact of statins on various COPD-related outcomes. This article reviews the current body of prospective evidence for use of statins in patients with COPD. A search of the PubMed/Medline database of English-language articles was conducted from 1964 through November 2015; references of relevant articles were also reviewed for qualifying studies. Prospective studies of all types relating to statin use in patients with COPD were included if they had COPD- or respiratory-related outcomes; ultimately, eight studies were identified for this review. Statin effects on exacerbation rates, mortality, and inflammatory markers in patients with COPD are discussed. Strong prospective evidence does not currently exist to suggest that statins provide a clinical benefit in patients with COPD who do not have other CVD risk factors. Benefits from statins that have been illustrated are likely explained by their impact on underlying CVD risk factors rather than the COPD disease process. An opportunity exists for unanswered questions to be addressed in future studies.

An Official American Thoracic Society/European Respiratory Society Statement: Research questions in chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity, mortality, and resource use worldwide. The goal of this Official American Thoracic Society (ATS)/European Respiratory Society (ERS) Research Statement is to describe evidence related to diagnosis, assessment, and management; identify gaps in knowledge; and make recommendations for future research. It is not intended to provide clinical practice recommendations on COPD diagnosis and management.

METHODS

Clinicians, researchers, and patient advocates with expertise in COPD were invited to participate. A literature search of Medline was performed, and studies deemed relevant were selected. The search was not a systematic review of the evidence. Existing evidence was appraised and summarized, and then salient knowledge gaps were identified.

RESULTS

Recommendations for research that addresses important gaps in the evidence in all areas of COPD were formulated via discussion and consensus.

CONCLUSIONS

Great strides have been made in the diagnosis, assessment, and management of COPD as well as understanding its pathogenesis. Despite this, many important questions remain unanswered. This ATS/ERS Research Statement highlights the types of research that leading clinicians, researchers, and patient advocates believe will have the greatest impact on patient-centered outcomes.

An official American Thoracic Society/European Respiratory Society statement: research questions in COPD

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity, mortality, and resource use worldwide. The goal of this official American Thoracic Society (ATS)/European Respiratory Society (ERS) research statement is to describe evidence related to diagnosis, assessment and management; identify gaps in knowledge; and make recommendations for future research. It is not intended to provide clinical practice recommendations on COPD diagnosis and management.

Clinicians, researchers, and patient advocates with expertise in COPD were invited to participate. A literature search of Medline was performed, and studies deemed relevant were selected. The search was not a systematic review of the evidence. Existing evidence was appraised and summarised, and then salient knowledge gaps were identified.

Recommendations for research that addresses important gaps in the evidence in all areas of COPD were formulatedviadiscussion and consensus.

Great strides have been made in the diagnosis, assessment and management of COPD, as well as understanding its pathogenesis. Despite this, many important questions remain unanswered. This ATS/ERS research statement highlights the types of research that leading clinicians, researchers, and patient advocates believe will have the greatest impact on patient-centred outcomes.

Second-hand cigarette smoke impairs bacterial phagocytosis in macrophages by modulating CFTR dependent lipid-rafts

Introduction

First/Second-hand cigarette-smoke (FHS/SHS) exposure weakens immune defenses inducing chronic obstructive pulmonary disease (COPD) but the underlying mechanisms are not fully understood. Hence, we evaluated if SHS induced changes in membrane/lipid-raft (m-/r)-CFTR (cystic fibrosis transmembrane conductance regulator) expression/activity is a potential mechanism for impaired bacterial phagocytosis in COPD.

Methods

RAW264.7 murine macrophages were exposed to freshly prepared CS-extract (CSE) containing culture media and/or Pseudomonas-aeruginosa-PA01-GFP for phagocytosis (fluorescence-microscopy), bacterial survival (colony-forming-units-CFU), and immunoblotting assays. The CFTR-expression/activity and lipid-rafts were modulated by transient-transfection or inhibitors/inducers. Next, mice were exposed to acute/sub-chronic-SHS or room-air (5-days/3-weeks) and infected with PA01-GFP, followed by quantification of bacterial survival by CFU-assay.

Results

We investigated the effect of CSE treatment on RAW264.7 cells infected by PA01-GFP and observed that CSE treatment significantly (p<0.01) inhibits PA01-GFP phagocytosis as compared to the controls. We also verified this in murine model, exposed to acute/sub-chronic-SHS and found significant (p<0.05, p<0.02) increase in bacterial survival in the SHS-exposed lungs as compared to the room-air controls. Next, we examined the effect of impaired CFTR ion-channel-activity on PA01-GFP infection of RAW264.7 cells using CFTR172-inhibitor and found no significant change in phagocytosis. We also similarly evaluated the effect of a CFTR corrector-potentiator compound, VRT-532, and observed no significant rescue of CSE impaired PA01-GFP phagocytosis although it significantly (p<0.05) decreases CSE induced bacterial survival. Moreover, induction of CFTR expression in macrophages significantly (p<0.03) improves CSE impaired PA01-GFP phagocytosis as compared to the control. Next, we verified the link between m-/r-CFTR expression and phagocytosis using methyl-β-cyclodextran (CD), as it is known to deplete CFTR from membrane lipid-rafts. We observed that CD treatment significantly (p<0.01) inhibits bacterial phagocytosis in RAW264.7 cells and adding CSE further impairs phagocytosis suggesting synergistic effect on CFTR dependent lipid-rafts.

Conclusion

Our data suggest that SHS impairs bacterial phagocytosis by modulating CFTR dependent lipid-rafts.

Mean platelet volume is decreased during an acute exacerbation of chronic obstructive pulmonary disease

BACKGROUND AND OBJECTIVE

An increased mean platelet volume (MPV) is an early marker of platelet activation. Activated platelets play a role in atherogenesis, inflammation and atherothrombosis. Chronic obstructive pulmonary disease (COPD) is associated with cardiovascular disease-related mortality. The aim of the study is to measure the MPV in patients with stable and exacerbated COPD.

METHODS

We investigated the peripheral blood cell count parameters, C-reactive protein (CRP), fibrinogen, lung function parameters and arterial blood gas analysis in patients with COPD and in controls. Seventy participants were investigated at admission for an acute exacerbation of COPD and reassessed when stable. Seventy controls were matched for age, gender, body mass index, medication use and smoking.

RESULTS

Participants with an exacerbation of COPD had lower MPV and higher CRP, white blood cells (WBC) and fibrinogen compared with when in stable phase of COPD and controls. MPV was also lower in patients in stable phase COPD compared with controls. Negative correlations between MPV and CRP, and between MPV and platelet count were present in patients in stable and exacerbation of COPD.

CONCLUSIONS

The findings show that COPD patients, during acute exacerbation and in stable phase, have lower MPV compared with healthy controls; the MPV increase once patients have recovered from their exacerbation of COPD.

Dry powder formulation of simvastatin

OBJECTIVES

This study focuses on the development of a dry powder inhaler (DPI) formulation of simvastatin (SV), and the effects of SV on the respiratory epithelium.

METHODS

Micronised SV samples were prepared by dry jet-milling. The long-term chemical stability and physicochemical properties of the formulations were characterised in terms of particles size, morphology, thermal and moisture responses. Furthermore, in vitro aerosol depositions were performed. The formulation was evaluated for cell viability and its effect on cilia beat activity, using ciliated nasal epithelial cells in vitro. The formulation transport across an established air interface Calu-3 bronchial epithelial cells and its ability to reduce mucus secretion was also investigated.

RESULTS

The particle size of the SV formulation and its aerosol performance were appropriate for inhalation therapy. Moreover, the formulation was found to be non-toxic to pulmonary epithelia cells and cilia beat activity up to a concentration of 10(-6) M. Transport studies revealed that SV has the ability to penetrate into airway epithelial cells and is converted into its active SV hydroxy acid metabolite. Single dose of SV DPI also decreased mucus production after 4 days of dosing.

CONCLUSION

This therapy could potentially be used for the local treatment of diseases like chronic obstructive pulmonary disease, cystic fibrosis, and bronchiectasis given its anti-inflammatory effects and ability to reduce mucus production.

Novel simvastatin inhalation formulation and characterisation

Simvastatin (SV), a drug of the statin class currently used orally as an anti-cholesterolemic via the inhibition of the 3-hydroxy-3-methyl-glutaryl-Coenzyme A (HMG-CoA) reductase, has been found not only to reduce cholesterol but also to have several other pharmacological actions that might be beneficial in airway inflammatory diseases. Currently, there is no inhalable formulation that could deliver SV to the lungs. In this study, a pressurised metered-dose inhaler (pMDI) solution formulation of SV was manufactured, with ethanol as a co-solvent, and its aerosol performance and physico-chemical properties investigated. A pMDI solution formulation containing SV and 6% w/w ethanol was prepared. This formulation was assessed visually and quantitatively for SV solubility. Furthermore, the aerosol performance (using Andersen Cascade impactor at 28.3 L/min) and active ingredient chemical stability up to 6 months at different storage temperatures, 4 and 25°C, were also evaluated. The physico-chemical properties of the SV solution pMDI were also characterised by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and laser diffraction. The aerosol particles, determined using scanning electron microscopy (SEM), presented a smooth surface morphology and were spherical in shape. The aerosol produced had a fine particle fraction of 30.77 ± 2.44% and a particle size distribution suitable for inhalation drug delivery. Furthermore, the short-term chemical stability showed the formulation to be stable at 4°C for up to 6 months, whilst at 25°C, the formulation was stable up to 3 months. In this study, a respirable and stable SV solution pMDI formulation for inhalation has been presented that could potentially be used clinically as an anti-inflammatory therapy for the treatment of several lung diseases.

Novel simvastatin inhalation formulation and characterisation

Simvastatin (SV), a drug of the statin class currently used orally as an anti-cholesterolemic via the inhibition of the 3-hydroxy-3-methyl-glutaryl-Coenzyme A (HMG-CoA) reductase, has been found not only to reduce cholesterol but also to have several other pharmacological actions that might be beneficial in airway inflammatory diseases. Currently, there is no inhalable formulation that could deliver SV to the lungs. In this study, a pressurised metered-dose inhaler (pMDI) solution formulation of SV was manufactured, with ethanol as a co-solvent, and its aerosol performance and physico-chemical properties investigated. A pMDI solution formulation containing SV and 6% w/w ethanol was prepared. This formulation was assessed visually and quantitatively for SV solubility. Furthermore, the aerosol performance (using Andersen Cascade impactor at 28.3 L/min) and active ingredient chemical stability up to 6 months at different storage temperatures, 4 and 25°C, were also evaluated. The physico-chemical properties of the SV solution pMDI were also characterised by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and laser diffraction. The aerosol particles, determined using scanning electron microscopy (SEM), presented a smooth surface morphology and were spherical in shape. The aerosol produced had a fine particle fraction of 30.77 ± 2.44% and a particle size distribution suitable for inhalation drug delivery. Furthermore, the short-term chemical stability showed the formulation to be stable at 4°C for up to 6 months, whilst at 25°C, the formulation was stable up to 3 months. In this study, a respirable and stable SV solution pMDI formulation for inhalation has been presented that could potentially be used clinically as an anti-inflammatory therapy for the treatment of several lung diseases.

Targeting the mevalonate cascade as a new therapeutic approach in heart disease, cancer and pulmonary disease

The cholesterol biosynthesis pathway, also known as the mevalonate (MVA) pathway, is an essential cellular pathway that is involved in diverse cell functions. The enzyme 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (HMGCR) is the rate-limiting step in cholesterol biosynthesis and catalyzes the conversion of HMG-CoA to MVA. Given its role in cholesterol and isoprenoid biosynthesis, the regulation of HMGCR has been intensely investigated. Because all cells require a steady supply of MVA, both the sterol (i.e. cholesterol) and non-sterol (i.e. isoprenoid) products of MVA metabolism exert coordinated feedback regulation on HMGCR through different mechanisms. The proper functioning of HMGCR as the proximal enzyme in the MVA pathway is essential under both normal physiologic conditions and in many diseases given its role in cell cycle pathways and cell proliferation, cholesterol biosynthesis and metabolism, cell cytoskeletal dynamics and stability, cell membrane structure and fluidity, mitochondrial function, proliferation, and cell fate. The blockbuster statin drugs ('statins') directly bind to and inhibit HMGCR, and their use for the past thirty years has revolutionized the treatment of hypercholesterolemia and cardiovascular diseases, in particular coronary heart disease. Initially thought to exert their effects through cholesterol reduction, recent evidence indicates that statins also have pleiotropic immunomodulatory properties independent of cholesterol lowering. In this review we will focus on the therapeutic applications and mechanisms involved in the MVA cascade including Rho GTPase and Rho kinase (ROCK) signaling, statin inhibition of HMGCR, geranylgeranyltransferase (GGTase) inhibition, and farnesyltransferase (FTase) inhibition in cardiovascular disease, pulmonary diseases (e.g. asthma and chronic obstructive pulmonary disease (COPD)), and cancer.

Managing older patients with coexistent asthma and chronic obstructive pulmonary disease: diagnostic and therapeutic challenges

Asthma and chronic obstructive pulmonary disease (COPD) are common obstructive airway diseases, especially among older people. These conditions are associated with a significant and increasing disease burden. The diagnosis and management of asthma and COPD in older populations are complex, and consequently clinicians are faced with many therapeutic and diagnostic challenges. Both aging and obstructive airway diseases are associated with complex co-morbidities and these coexisting illnesses confound management. Moreover, the age-related physiological changes that occur in the lungs may lead to airflow limitation, and this may be difficult to distinguish from an active disease state. In practice, management of asthma and COPD is informed by disease-specific clinical practice guidelines; however, most older people with these conditions are excluded from clinical trials that are designed to inform practice, creating major evidence gaps. Furthermore, seldom do clinical practice guidelines consider the complexities of management in older populations. The problems experienced by older people are complex and multifactorial and our approach to management must reflect these challenges. Opportunities exist to improve the management and outcomes for older people with obstructive airway disease and there is an urgent need for clinical trials to test management approaches in this population; current research must consider the challenges and evidence gaps that exist.

Trolox contributes to Nrf2-mediated protection of human and murine primary alveolar type II cells from injury by cigarette smoke

Cigarette smoke (CS) is a main risk factor for chronic obstructive pulmonary disease (COPD). Oxidative stress induced by CS causes DNA and lung damage. Oxidant/antioxidant imbalance occurs in the distal air spaces of smokers and in patients with COPD. We studied the effect of oxidative stress generated by CS both in vivo and in vitro on murine primary alveolar type II (ATII) cells isolated from nuclear erythroid 2-related factor-2 (Nrf2)(-/-) mice. We determined human primary ATII cell injury by CS in vitro and analyzed ATII cells isolated from smoker and non-smoker lung donors ex vivo. We also studied whether trolox (water-soluble derivative of vitamin E) could protect murine and human ATII cells against CS-induced DNA damage and/or decrease injury. We analyzed oxidative stress by 4-hydroxynonenal expression, reactive oxygen species (ROS) generation by Amplex Red Hydrogen Peroxide Assay, Nrf2, heme oxygenase 1, p53 and P53-binding protein 1 (53BP1) expression by immonoblotting, Nrf2 nuclear translocation, Nrf2 and p53 DNA-binding activities, apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and cytokine production by ELISA. We found that ATII cells isolated from Nrf2(-/-) mice are more susceptible to CS-induced oxidative DNA damage mediated by p53/53BP1 both in vivo and in vitro compared with wild-type mice. Therefore, Nrf2 activation is a key factor to protect ATII cells against injury by CS. Moreover, trolox abolished human ATII cell injury and decreased DNA damage induced by CS in vitro. Furthermore, we found higher inflammation and p53 mRNA expression by RT-PCR in ATII cells isolated from smoker lung donors in comparison with non-smokers ex vivo. Our results indicate that the Nrf2 and p53 cross talk in ATII cells affect the susceptibility of these cells to injury by CS. Trolox can protect against oxidative stress, genotoxicity and inflammation induced by CS through ROS scavenging mechanism, and serve as a potential antioxidant prevention strategy against oxidative injury of ATII cells in CS-related lung diseases.

Multiple dosing of simvastatin inhibits airway mucus production of epithelial cells: implications in the treatment of chronic obstructive airway pathologies

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterised by mucus hyper-production. This pathology, together with other inflammatory contributions, leads to airway obstruction and breathing complications. Newer therapeutic approaches are of increased interest, including the use of HMG-CoA reductase inhibitors. Retrospective studies have shown that statins are effective in reducing patient mortality and blood cytokines levels. These findings suggest statins may also provide a new therapeutic approach in COPD treatment.

PURPOSE

The aim of the present work was to study the transport of simvastatin (SV) across Calu-3 epithelial cells and to investigate its pharmacological action with respect to reduction in mucus production.

METHODS

Calu-3 cells were grown under liquid covered culture (LCC) conditions for transport studies in order to demonstrate the ability of SV to transport across the monolayer. For mucus detection, cells were grown under air interface culture (AIC) conditions. Samples collected for microscope analysis were stained with alcian blue; images of the stained cell surface were acquired and the mucus was quantified as the RGBB ratio.

RESULTS

SV was transported through the cell monolayer and 'retained' inside the Calu-3 cells. Colour analysis of stained Calu-3 monolayers microscope-images showed that chronic administration of SV for 14 days caused a significant inhibition in mucus production.

CONCLUSION

These findings suggest that local delivery of SV directly to the lungs may provide a promising treatment and potential disease management approach of COPD, with significant effects on mucus reduction.

PET imaging of tumor associated macrophages using mannose coated 64Cu liposomes

Macrophages within the tumor microenvironment (TAMs) have been shown to play a major role in the growth and spread of many types of cancer. Cancer cells produce cytokines that cause macrophages to express scavenger receptors (e.g. the mannose receptor) and factors that facilitate tissue and blood vessel growth, suppress T cell mediated anti-tumor activity, and express enzymes that can break down the extracellular matrix, thereby promoting metastasis. We have designed a mannosylated liposome (MAN-LIPs) and show that it accumulates in TAMs in a mouse model of pulmonary adenocarcinoma. These liposomes are loaded with (64)Cu to allow tracking by PET imaging, and contain a fluorescent dye in the lipid bilayer permitting subsequent fluorescence microscopy. We injected these liposomes into a mouse model of lung cancer. In vivo PET images were acquired 6 h after injection followed by the imaging of select excised organs. MAN-LIPs accumulated in TAMs and exhibited little accumulation in remote lung areas. MAN-LIPs are a promising new vehicle for the delivery of imaging agents to lung TAMs. In addition to imaging, MAN-LIPs hold the potential for delivery of therapeutic agents to the tumor microenvironment.

Treatment of COPD: moving beyond the lungs

We still do not know whether the successful treatment of the comorbid diseases associated with COPD, mainly cardiovascular disease, also positively influences the course of the lung disease because so far there are few definite data documenting that treatment of COPD comorbidities will reduce morbidity and mortality rates in these patients. Observational studies suggest that COPD patients treated with statins, angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor blockers, and β-adrenoceptor blockers may have improved survival and reduced hospitalisation from exacerbations. Progress in basic and translational research has led to a better understanding of pharmacological mechanisms that may explain the effects of these drugs on COPD and some small clinical trial activity is beginning to generate promising results.