Oral non-steroidal anti-inflammatory drug therapy for lung disease in cystic fibrosis

Serious infectious events and ibuprofen administration in pediatrics: a narrative review in the era of COVID-19 pandemic

Purpose of review

Despite its recognized efficacy and tolerability profile, during the last decade a rise of adverse events following ibuprofen administration in children has been reported, including a possible role in worsening the clinical course of infections. Our aim was to critically evaluate the safety of ibuprofen during the course of pediatric infectious disease in order to promote its appropriate use in children.

Recent findings

Ibuprofen is associated with severe necrotizing soft tissue infections (NSTI) during chickenpox course. Pre-hospital use of ibuprofen seems to increase the risk of complicated pneumonia in children. Conflicting data have been published in septic children, while ibuprofen in the setting of Cystic Fibrosis (CF) exacerbations is safe and efficacious. No data is yet available for ibuprofen use during COVID-19 course.

Summary

Ibuprofen should not be recommended for chickenpox management. Due to possible higher risks of complicated pneumonia, we suggest caution on its use in children with respiratory symptoms. While it remains unclear whether ibuprofen may have harmful effects during systemic bacterial infection, its administration is recommended in CF course. Despite the lack of data, it is seems cautious to prefer the use of paracetamol during COVID-19 acute respiratory distress syndrome in children.

The Role of Specialized Pro-Resolving Mediators in Cystic Fibrosis Airways Disease

Cystic Fibrosis (CF) is a recessive genetic disease due to mutations of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene encoding the CFTR chloride channel. The ion transport abnormalities related to CFTR mutation generate a dehydrated airway surface liquid (ASL) layer, which is responsible for an altered mucociliary clearance, favors infections and persistent inflammation that lead to progressive lung destruction and respiratory failure. The inflammatory response is normally followed by an active resolution phase to return to tissue homeostasis, which involves specialized pro-resolving mediators (SPMs). SPMs promote resolution of inflammation, clearance of microbes, tissue regeneration and reduce pain, but do not evoke unwanted immunosuppression. The airways of CF patients showed a decreased production of SPMs even in the absence of pathogens. SPMs levels in the airway correlated with CF patients' lung function. The prognosis for CF has greatly improved but there remains a critical need for more effective treatments that prevent excessive inflammation, lung damage, and declining pulmonary function for all CF patients. This review aims to highlight the recent understanding of CF airway inflammation and the possible impact of SPMs on functions that are altered in CF airways.

Oral non-steroidal anti-inflammatory drug therapy for lung disease in cystic fibrosis

BACKGROUND

Progressive lung damage causes most deaths in cystic fibrosis. Non-steroidal anti-inflammatory drugs (such as ibuprofen) may prevent progressive pulmonary deterioration and morbidity in cystic fibrosis. This is an update of a previously published review.

OBJECTIVES

To assess the effectiveness of treatment with oral non-steroidal anti-inflammatory drugs in cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches, hand searches of relevant journals and abstract books of conference proceedings. We contacted manufacturers of non-steroidal anti-inflammatory drugs and searched online trials registries.Latest search of the Group's Trials Register: 21 November 2018.

SELECTION CRITERIA

Randomized controlled trials comparing oral non-steroidal anti-inflammatory drugs, at any dose for at least two months, to placebo in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for inclusion the review and their potential risk of bias. Two authors independently rated the quality of the evidence for each outcome using the GRADE guidelines.

MAIN RESULTS

The searches identified 17 trials; four are included (287 participants aged five to 39 years; maximum follow-up of four years) and one is currently awaiting classification pending publication of the full trial report and two are ongoing. Three trials compared ibuprofen to placebo (two from the same center with some of the same participants); one trial assessed piroxicam versus placebo.The three ibuprofen trials were deemed to have good or adequate methodological quality, but used various outcomes and summary measures. Reviewers considered measures of lung function, nutritional status, radiological assessment of pulmonary involvement, intravenous antibiotic usage, hospital admissions, survival and adverse effects. Combined data from the two largest ibuprofen trials showed a lower annual rate of decline for lung function, % predicted forced expiratory volume in one second (FEV1), mean difference (MD) 1.32 (95% confidence interval (CI) 0.21 to 2.42) (moderate-quality evidence); forced vital capacity (FVC), MD 1.27 (95% CI 0.26 to 2.28) (moderate-quality evidence); forced expiratory flow (FEF25%-75%), MD 1.80 (95% CI 0.15 to 3.45). The post hoc analysis of data from two trials split by age showed a slower rate of annual decline of FEV1 % predicted and FVC in the ibuprofen group in younger children, MD 1.41% (95% CI 0.03 to 2.80) (moderate-quality evidence) and MD 1.32% (95% CI 0.04 to 2.60) (moderate-quality evidence) respectively. Data from four trials demonstrated the proportion of participants with at least one hospitalization may be slightly lower in the ibuprofen group compared to placebo, Peto odds ratio 0.61 (95% CI 0.37 to 1.01) (moderate-quality evidence). In one trial, long-term use of high-dose ibuprofen was associated with reduced intravenous antibiotic usage, improved nutritional and radiological pulmonary status. No major adverse effects were reported, but the power of the trials to identify clinically important differences in the incidence of adverse effects was low.We did not have any concerns with regards to risk of bias for the trial comparing piroxicam to placebo. However, the trial did not report many data in a form that we could analyze in this review. No data were available for the review's primary outcome of lung function; available data for hospital admissions showed no difference between the groups. No analyzable data were available for any other review outcome.

AUTHORS' CONCLUSIONS

High-dose ibuprofen can slow the progression of lung disease in people with cystic fibrosis, especially in children, which suggests that strategies to modulate lung inflammation can be beneficial for people with cystic fibrosis.

Roles, Actions, and Therapeutic Potential of Specialized Pro-resolving Lipid Mediators for the Treatment of Inflammation in Cystic Fibrosis

Non-resolving inflammation is the main mechanism of morbidity and mortality among patients suffering from cystic fibrosis (CF), the most common life-threatening human genetic disease. Resolution of inflammation is an active process timely controlled by endogenous specialized pro-resolving lipid mediators (SPMs) produced locally in inflammatory loci to restrain this innate response, prevent further damages to the host, and permit return to homeostasis. Lipoxins, resolvins, protectins, and maresins are SPM derived from polyunsaturated fatty acids that limit excessive leukocyte infiltration and pro-inflammatory signals, stimulate innate microbial killing, and enhance resolution. Their unique chemical structures, receptors, and bioactions are being elucidated. Accruing data indicate that SPMs carry protective functions against unrelenting inflammation and infections in preclinical models and human CF systems. Here, we reviewed their roles and actions in controlling resolution of inflammation, evidence for their impairment in CF, and proofs of principle for their exploitation as innovative, non-immunosuppressive drugs to address inflammation and infections in CF.

Antimicrobial Activity of Ibuprofen against Cystic Fibrosis-Associated Gram-Negative Pathogens

Clinical trials have demonstrated the benefits of ibuprofen therapy in cystic fibrosis (CF) patients, an effect that is currently attributed to ibuprofen's anti-inflammatory properties. Yet, a few previous reports demonstrated an antimicrobial activity of ibuprofen as well, although none investigated its direct effects on the pathogens found in the CF lung, which is the focus of this work. Determination of ibuprofen's in vitro antimicrobial activity against Pseudomonas aeruginosa and Burkholderia species strains through measurements of the endpoint number of CFU and growth kinetics showed that ibuprofen reduced the growth rate and bacterial burden of the tested strains in a dose-dependent fashion. In an in vitroPseudomonas biofilm model, a reduction in the rate of biomass accumulation over 8 h of growth with ibuprofen treatment was observed. Next, an acute Pseudomonas pneumonia model was used to test this antimicrobial activity after the oral delivery of ibuprofen. Following intranasal inoculation, ibuprofen-treated mice exhibited lower CFU counts and improved survival compared with the control animals. Preliminary biodistribution studies performed after the delivery of ibuprofen to mice by aerosol demonstrated a rapid accumulation of ibuprofen in serum and minimum retention in lung tissue and bronchoalveolar lavage fluid. Therefore, ibuprofen-encapsulated polymeric nanoparticles (Ibu-NPs) were formulated to improve the pharmacokinetic profile. Ibu-NPs formulated for aerosol delivery inhibited the growth of P. aeruginosa in vitro and may provide a convenient dosing method. These results provide an additional explanation for the previously observed therapeutic effects of ibuprofen in CF patients and further strengthen the argument for its use by these patients.

Digitoxin for Airway Inflammation in Cystic Fibrosis: Preliminary Assessment of Safety, Pharmacokinetics, and Dose Finding

RATIONALE

Cystic fibrosis (CF) lung disease progresses by a combination of airway inflammation, bacterial colonization, and infection. Airway inflammation is predominantly neutrophilic and complicates airway clearance therapies through cellular debris; excessive DNA; excessive and viscous mucus; and high concentrations of neutrophils, IL-8, and related cytokines liberated along the nuclear factor-κB signaling pathway.

OBJECTIVES

We conducted a preliminary, single-site, randomized, double-blind, placebo-controlled study to evaluate the effects over 28 days of two dose levels (0.05 mg and 0.1 mg daily) of an older cardiac glycoside, digitoxin, as compared with placebo, on safety, pharmacokinetics, and inflammatory markers in induced sputum obtained from 24 subjects with mild to moderate CF lung disease.

METHODS

Patients with CF 18-45 years old with any genotype combination were eligible. The primary objective was to measure the effects of digitoxin on IL-8 and neutrophil counts in induced sputum. Secondary objectives were to measure (1) the pharmacokinetics of digitoxin in sera of patients with stable CF; (2) safety indices, including ECG changes and sputum microbiology; (3) the effect of digitoxin on gene expression in nasal epithelial cells of patients with stable CF; and (4) quality-of-life scores using the Cystic Fibrosis Questionnaire-Revised.

MEASUREMENTS AND MAIN RESULTS

It took several weeks to achieve a therapeutic serum level of digitoxin in subjects with CF. No safety concerns emerged during the study. Digitoxin treatment showed a trend toward reduction in sputum free neutrophil elastase and neutrophil counts, but not a reduction in sputum IL-8. Digitoxin treatment did not reach statistical significance for the primary or secondary outcome measures over the 28-day study period. However, the nasal mRNA from the group receiving 0.1 mg of digitoxin daily had a distinct distribution of global gene expression levels as compared with either the 0.05-mg dose or placebo treatment. The mRNAs encoding chemokine/cytokine or cell surface receptors in immune cells were decreased in nasal epithelial cells at the higher dose, leading to pathway-mediated reductions in IL-8, IL-6, lung epithelial inflammation, neutrophil recruitment, and mucus hypersecretion.

CONCLUSIONS

At a dose of 0.1 mg daily for 28 days, digitoxin was safe for adults with CF lung disease, but it did not achieve a significant decrease in sputum inflammatory markers. Clinical trial registered with www.clinicaltrials.gov (NCT00782288).

Interval estimation of the overall treatment effect in a meta-analysis of a few small studies with zero events

When a meta-analysis consists of a few small trials that report zero events, accounting for heterogeneity in the (interval) estimation of the overall effect is challenging. Typically, we predefine meta-analytical methods to be employed. In practice, data poses restrictions that lead to deviations from the pre-planned analysis, such as the presence of zero events in at least one study arm. We aim to explore heterogeneity estimators behaviour in estimating the overall effect across different levels of sparsity of events. We performed a simulation study that consists of two evaluations. We considered an overall comparison of estimators unconditional on the number of observed zero cells and an additional one by conditioning on the number of observed zero cells. Estimators that performed modestly robust when (interval) estimating the overall treatment effect across a range of heterogeneity assumptions were the Sidik-Jonkman, Hartung-Makambi and improved Paul-Mandel. The relative performance of estimators did not materially differ between making a predefined or data-driven choice. Our investigations confirmed that heterogeneity in such settings cannot be estimated reliably. Estimators whose performance depends strongly on the presence of heterogeneity should be avoided. The choice of estimator does not need to depend on whether or not zero cells are observed.

Brazilian guidelines for the diagnosis and treatment of cystic fibrosis

Cystic fibrosis (CF) is an autosomal recessive genetic disorder characterized by dysfunction of the CFTR gene. It is a multisystem disease that most often affects White individuals. In recent decades, various advances in the diagnosis and treatment of CF have drastically changed the scenario, resulting in a significant increase in survival and quality of life. In Brazil, the current neonatal screening program for CF has broad coverage, and most of the Brazilian states have referral centers for the follow-up of individuals with the disease. Previously, CF was limited to the pediatric age group. However, an increase in the number of adult CF patients has been observed, because of the greater number of individuals being diagnosed with atypical forms (with milder phenotypic expression) and because of the increase in life expectancy provided by the new treatments. However, there is still great heterogeneity among the different regions of Brazil in terms of the access of CF patients to diagnostic and therapeutic methods. The objective of these guidelines was to aggregate the main scientific evidence to guide the management of these patients. A group of 18 CF specialists devised 82 relevant clinical questions, divided into five categories: characteristics of a referral center; diagnosis; treatment of respiratory disease; gastrointestinal and nutritional treatment; and other aspects. Various professionals working in the area of CF in Brazil were invited to answer the questions devised by the coordinators. We used the PubMed database to search the available literature based on keywords, in order to find the best answers to these questions.

Is the perceived placebo effect comparable between adults and children? A meta-regression analysis

BACKGROUND

A potential larger perceived placebo effect in children compared with adults could influence the detection of the treatment effect and the extrapolation of the treatment benefit from adults to children. This study aims to explore this potential difference, using a meta-epidemiological approach.

METHODS

A systematic review of the literature was done to identify trials included in meta-analyses evaluating a drug intervention with separate data for adults and children. The standardized mean change and the proportion of responders (binary outcomes) were used to calculate the perceived placebo effect. A meta-regression analysis was conducted to test for the difference between adults and children of the perceived placebo effect.

RESULTS

For binary outcomes, the perceived placebo effect was significantly more favorable in children compared with adults (β = 0.13; P = 0.001). Parallel group trials (β = -1.83; P < 0.001), subjective outcomes (β = -0.76; P < 0.001), and the disease type significantly influenced the perceived placebo effect.

CONCLUSION

The perceived placebo effect is different between adults and children for binary outcomes. This difference seems to be influenced by the design, the disease, and outcomes. Calibration of new studies for children should consider cautiously the placebo effect in children.

Cystic Fibrosis: Microbiology and Host Response

The earliest descriptions of lung disease in people with cystic fibrosis (CF) showed the involvement of 3 interacting pathophysiologic elements in CF airways: mucus obstruction, inflammation, and infection. Over the past 7 decades, our understanding of CF respiratory microbiology and inflammation has evolved with the introduction of new treatments, increased longevity, and increasingly sophisticated laboratory techniques. This article reviews the current understanding of infection and inflammation and their roles in CF lung disease. It also discusses how this constantly evolving information is used to inform current therapeutic strategies, measures and predictors of disease severity, and research priorities.

Current and future treatment options for cystic fibrosis lung disease: latest evidence and clinical implications

Treatment for cystic fibrosis (CF) has conventionally targeted downstream consequences of the defect such as mucus plugging and infection. More recently, significant advances have been made in treating the root cause of the disease, namely a defective CF transmembrane conductance regulator (CFTR) gene. This review summarizes current pulmonary treatment options and highlights advances in research and development of new therapies.

Oral non-steroidal anti-inflammatory drug therapy for lung disease in cystic fibrosis

BACKGROUND

Progressive lung damage causes most deaths in cystic fibrosis. Non-steroidal anti-inflammatory drugs (such as ibuprofen) may prevent progressive pulmonary deterioration and morbidity in cystic fibrosis.

OBJECTIVES

To assess the effectiveness of treatment with non-steroidal anti-inflammatory drugs in cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches, hand searches of relevant journals and abstract books of conference proceedings. We contacted manufacturers of non-steroidal anti-inflammatory drugs.Latest search of the Group's Trials Register: 04 February 2016.

SELECTION CRITERIA

Randomized controlled trials comparing oral non-steroidal anti-inflammatory drugs, at any dose for at least two months, to placebo in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for inclusion the review and their potential risk of bias.

MAIN RESULTS

The searches identified 10 trials; four are included (287 participants aged five to 39 years; maximum follow up of four years) and one is currently awaiting classification pending publication of the full trial report. Three trials compared ibuprofen to placebo (two from the same centre with some of the same participants); one trial assessed piroxicam versus placebo.The three ibuprofen trials were deemed to have good or adequate methodological quality, but used various outcomes and summary measures. Reviewers considered measures of lung function, nutritional status, radiological assessment of pulmonary involvement, intravenous antibiotic usage, hospital admissions, survival and adverse effects. Combined data from the two largest ibuprofen trials showed a significantly lower annual rate of decline for lung function, percent predicted forced expiratory volume in one second mean difference 1.32 (95% confidence interval 0.21 to 2.42); forced vital capacity mean difference 1.27 (95% confidence interval 0.26 to 2.28); forced expiratory flow (25-75%) mean difference 1.80 (95% confidence interval 0.15 to 3.45). The post-hoc analysis of data from two trials split by age showed a statistically significant slower rate of annual decline of percent predicted forced expiratory volume in one second and forced vital capacity in the ibuprofen group in younger children, mean difference 1.41% (95% confidence interval 0.03 to 2.80) and mean difference 1.32% (95% confidence interval 0.04 to 2.60) respectively. In one trial, long-term use of high-dose ibuprofen was associated with reduced intravenous antibiotic usage, improved nutritional and radiological pulmonary status. No major adverse effects were reported, but the power of the trials to identify clinically important differences in the incidence of adverse effects was low.We did not have any concerns with regards to risk of bias for the trial comparing piroxicam to placebo. However, the trial did not report many data in a form that we could analyse in this review. No data were available for the review's primary outcome of lung function; available data for hospital admissions showed no difference between the groups. No analysable data were available for any other review outcome.

AUTHORS' CONCLUSIONS

High-dose ibuprofen can slow the progression of lung disease in people with cystic fibrosis, especially in children, which suggests that strategies to modulate lung inflammation can be beneficial for people with cystic fibrosis.

Safety of Drugs during Pregnancy and Breastfeeding in Cystic Fibrosis Patients

Health management of cystic fibrosis (CF) patients should be maximized during pregnancy and breastfeeding because of its significant impact on the maternal and newborn outcomes. Thus, numerous drugs will have to be continued during pregnancy and lactation. Most of the drugs representing CF treatment lines cross the placenta or are excreted into human milk. Research addressing the risks and benefits of drugs used in CF patients during pregnancy and lactation is often incomplete or challenged by limited methodology, which often leads to conflicting or inconclusive results. Yet, potential treatment benefits for CF pregnant patients most often outbalance potential risks for the unborn child.

Inhaled non-steroid anti-inflammatories for children and adults with bronchiectasis

BACKGROUND

Chronic neutrophilic inflammation, in both the presence and absence of infection, is a feature of bronchiectasis in adults and children. The anti-inflammatory properties of non-steroid anti-inflammatory drugs (NSAIDs) may be beneficial in reducing airway inflammation, thus potentially improving lung function and quality of life in patients with bronchiectasis.

OBJECTIVES

To evaluate the efficacy of inhaled NSAIDs in the management of non-cystic fibrosis bronchiectasis in children and adults:• during stable bronchiectasis; and• for reduction of:∘ severity and frequency of acute respiratory exacerbations; and∘ long-term pulmonary decline.

SEARCH METHODS

We searched the Cochrane Airways Group Trials Register, which includes reports identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). We also searched the trial registry ClinicalTrials.gov and the World Health Organization (WHO) trial portal. We carried out the latest searches on 22 September 2015.

SELECTION CRITERIA

All randomised controlled trials comparing inhaled NSAIDs versus a control (placebo or usual treatment) in children or adults with bronchiectasis not related to cystic fibrosis.

DATA COLLECTION AND ANALYSIS

We reviewed the results of searches against predetermined criteria for inclusion.

MAIN RESULTS

One small, short-term trial was eligible for inclusion. We included this study of 25 adults with chronic lung disease (only 32% of people included in the trial had bronchiectasis), as the other conditions were linked to development of bronchiectasis, and all were characterised by chronic sputum production. We were not able to obtain separate data for people with a diagnosis of bronchiectasis. We judged that the study was at a high risk of selection bias.The primary outcome (mean difference in control of bronchiectasis severity, quality of life (Qol), cough scores) was not reported in the included study. The single trial in adults reported a significant reduction in sputum production over 14 days for the treatment group (inhaled indomethacin) compared with the placebo group (mean difference (MD) -75.00 g/day; 95% confidence interval (CI) -134.61 to -15.39) and a significant improvement in the Borg Dyspnoea Scale score (MD -1.90, 95% CI -3.15 to -0.65). We noted no significant differences between groups in lung function or blood indices and no reported adverse events.

AUTHORS' CONCLUSIONS

No new studies of adults or children have been conducted since the last version of this review was published. Therefore, final conclusions have not changed. Current evidence is insufficient to support or refute the use of inhaled NSAIDs for the management of bronchiectasis in adults or children. One small trial reported a reduction in sputum production and improved dyspnoea among adults with chronic lung disease who were treated with inhaled indomethacin, indicating that additional studies on the efficacy of NSAIDs for treatment of patients with bronchiectasis are warranted.

The Evolution of Cystic Fibrosis Care

Cystic fibrosis (CF) is the most common life-limiting inherited illness of whites. Most of the morbidity and mortality in CF stems from impaired mucociliary clearance leading to chronic, progressive airways obstruction and damage. Significant progress has been made in the care of patients with CF, with advances focused on improving mucociliary clearance, minimizing inflammatory damage, and managing infections; these advances include new antimicrobial therapies, mucolytic and osmotic agents, and antiinflammatory treatments. More recently, researchers have targeted disease-causing mutations using therapies to promote gene transcription and improve channel function, which has led to impressive physiologic changes in some patients. As we develop more advanced, allele-directed therapies for the management of CF, it will become increasingly important to understand the specific genetic and environmental interactions that cause the significant heterogeneity of lung disease seen in the CF population. This understanding of CF endotypes will allow for more targeted, personalized therapies for future patients. This article reviews the genetic and molecular basis of CF lung disease, the treatments currently available, and novel therapies that are in development.

Cystic fibrosis

Cystic fibrosis is an autosomal recessive, monogenetic disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The gene defect was first described 25 years ago and much progress has been made since then in our understanding of how CFTR mutations cause disease and how this can be addressed therapeutically. CFTR is a transmembrane protein that transports ions across the surface of epithelial cells. CFTR dysfunction affects many organs; however, lung disease is responsible for the vast majority of morbidity and mortality in patients with cystic fibrosis. Prenatal diagnostics, newborn screening and new treatment algorithms are changing the incidence and the prevalence of the disease. Until recently, the standard of care in cystic fibrosis treatment focused on preventing and treating complications of the disease; now, novel treatment strategies directly targeting the ion channel abnormality are becoming available and it will be important to evaluate how these treatments affect disease progression and the quality of life of patients. In this Primer, we summarize the current knowledge, and provide an outlook on how cystic fibrosis clinical care and research will be affected by new knowledge and therapeutic options in the near future. For an illustrated summary of this Primer, visit: http://go.nature.com/4VrefN.

Early pulmonary inflammation and lung damage in children with cystic fibrosis

Individuals with cystic fibrosis (CF) suffer progressive airway inflammation, infection and lung damage. Airway inflammation and infection are present from early in life, often before children are symptomatic. CF gene mutations cause changes in the CF transmembrane regulator protein that result in an aberrant airway microenvironment including airway surface liquid (ASL) dehydration, reduced ASL acidity, altered airway mucin and a dysregulated inflammatory response. This review discusses how an altered microenvironment drives CF lung disease before overt airway infection, the response of the CF airway to early infection, and methods to prevent inflammation and early lung disease.

Physiological impact of abnormal lipoxin A₄ production on cystic fibrosis airway epithelium and therapeutic potential

Lipoxin A₄ has been described as a major signal for the resolution of inflammation and is abnormally produced in the lungs of patients with cystic fibrosis (CF). In CF, the loss of chloride transport caused by the mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) Cl⁻ channel gene results in dehydration, mucus plugging, and reduction of the airway surface liquid layer (ASL) height which favour chronic lung infection and neutrophil based inflammation leading to progressive lung destruction and early death of people with CF. This review highlights the unique ability of LXA₄ to restore airway surface hydration, to stimulate airway epithelial repair, and to antagonise the proinflammatory program of the CF airway, circumventing some of the most difficult aspects of CF pathophysiology. The report points out novel aspects of the cellular mechanism involved in the physiological response to LXA₄, including release of ATP from airway epithelial cell via pannexin channel and subsequent activation of and P2Y11 purinoreceptor. Therefore, inadequate endogenous LXA₄ biosynthesis reported in CF exacerbates the ion transport abnormality and defective mucociliary clearance, in addition to impairing the resolution of inflammation, thus amplifying the vicious circle of airway dehydration, chronic infection, and inflammation.

Magnetoliposomes loaded with poly-unsaturated fatty acids as novel theranostic anti-inflammatory formulations

We describe the preparation, physico-chemical characterization and anti-inflammatory properties of liposomes containing the superparamagnetic nanoparticle Nanotex, the fluorescent dye Rhodamine-100 and omega-3 polyunsaturated fatty acid ethyl ester (ω-3 PUFA-EE), as theranostic anti-inflammatory agents. Liposomes were prepared after drying chloroform suspensions of egg phosphatidylcholine, hydration of the lipid film with aqueous phases containing or not Nanotex, Rhodamine-100 dye or ω-3 PUFA-EE, and eleven extrusion steps through nanometric membrane filters. This resulted in uniform preparations of liposomes of approximately 200 nm diameter. Extraliposomal contents were removed from the preparation by gel filtration chromatography. High Resolution Magic Angle Spinning ¹H NMR Spectroscopy of the liposomal preparations containing ω-3 PUFA-EE revealed well resolved ¹H resonances from highly mobile ω-3 PUFA-EE, suggesting the formation of very small (ca. 10 nm) ω-3 PUFA-EE nanogoticules, tumbling fast in the NMR timescale. Chloroform extraction of the liposomal preparations revealed additionally the incorporation of ω-3 PUFA-EE within the membrane domain. Water diffusion weighted spectra, indicated that the goticules of ω-3 PUFA-EE or its insertion in the membrane did not affect the average translational diffusion coefficient of water, suggesting an intraliposomal localization, that was confirmed by ultrafiltration. The therapeutic efficacy of these preparations was tested in two different models of inflammatory disease as inflammatory colitis or the inflammatory component associated to glioma development. Results indicate that the magnetoliposomes loaded with ω-3 PUFA-EE allowed MRI visualization in vivo and improved the outcome of inflammatory disease in both animal models, decreasing significantly colonic inflammation and delaying, or even reversing, glioma development. Together, our results indicate that magnetoliposomes loaded with ω-3 PUFA-EE may become useful anti-inflammatory agents for image guided drug delivery.

Factors associated with response to treatment of pulmonary exacerbations in cystic fibrosis patients

BACKGROUND

Pulmonary exacerbations are associated with significant lung function decline from baseline in cystic fibrosis (CF) and it is not well understood why some patients do not respond to antibiotic therapy. The objective of this study was to identify factors associated with lung function response to antibiotic treatment of pulmonary exacerbations.

METHODS

As a secondary analysis of a randomized, controlled trial of intravenous antibiotic treatment for pulmonary exacerbations in CF patients, we investigated whether baseline factors and changes in sputum bacterial density, serum or sputum inflammatory markers were associated with recovery of lung function and risk of subsequent exacerbation.

RESULTS

In 36 of the 70 exacerbations (51%), patients' lung function returned to >100% of their baseline at day 14 of antibiotic treatment; 34 exacerbations were classified as non-responders. Baseline characteristics were not significantly different between responders and non-responders. Less of a drop in FEV1 from baseline to exacerbation (OR 1.09, 95% CI 1.0, 1.18, p=0.04) as well as a greater decrease in sputum neutrophil elastase (OR 2.94, 95% CI 1.07, 8.06, p=0.04) were associated with response to antibiotic treatment at day 14. In addition, higher CRP (HR 1.35 (95% CI: 1.01, 1.78), p=0.04) and sputum neutrophil elastase (HR 1.71 (95% CI: 1.02, 2.88), p=0.04) at day 14 of antibiotic therapy were associated with an increased risk of subsequent exacerbation.

CONCLUSIONS

Inadequate reduction of inflammation during an exacerbation is associated with failure to recover lung function and increased risk of subsequent re-exacerbation in CF patients.

The role of Lipoxin A4 in Cystic Fibrosis Lung Disease

In Cystic Fibrosis (CF), mutations of the CFTR gene result in defective Cl(-) secretion and Na(+) hyperabsorption by epithelia which leads to airway lumen dehydration and mucus plugging and favours chronic bacterial colonization, persistent inflammation and progressive lung destruction. Beyond this general description, the pathogenesis of CF lung disease remains obscure due to an incomplete understanding of normal innate airway defense. This mini-review aims to highlight the role of the pro-resolution lipid mediator, Lipoxin A4, which is inadequately produced in CF, on several aspects of innate immunity that are altered in CF airway disease.