Effects of an Antioxidant-enriched Multivitamin in Cystic Fibrosis. A Randomized, Controlled, Multicenter Clinical Trial

Association of dietary overall antioxidant intake with all-cause and cause-specific mortality among adults with depression: evidence from NHANES 2005-2018

Higher intakes of individual antioxidants such as vitamins A, C, and E have been linked to mortality in the general population, but the association of overall antioxidant intake with mortality especially in depressed adults remains unclear. We aimed to investigate whether the dietary overall antioxidant intake is associated with all-cause and cause-specific mortality among depressed adults. This study included 3051 US adults with depression, who participated in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Patient Health Questionnaire-9 (PHQ-9) was used to define depression and evaluate depression severity. The dietary antioxidant quality score (DAQS) and dietary antioxidant index (DAI) were calculated based on the intakes of vitamins A, C, and E, zinc, selenium, and magnesium. A higher DAQS and DAI were significantly associated with lower depression scores (PHQ-9) (all P-trend < 0.05). For individual antioxidants, significant negative associations of vitamins A and E with all-cause mortality were observed. For overall antioxidant intake, the DAQS and DAI were inversely associated with all-cause and cancer mortality. Compared with participants in the lowest categories of DAQS and DAI, the corresponding HRs (95% CIs) in the highest categories were 0.63 (0.42-0.93) and 0.70 (0.49-0.98) for all-cause mortality and 0.39 (0.17-0.87) and 0.43 (0.21-0.88) for cancer mortality, respectively. The overall dietary antioxidant intake was beneficially associated with all-cause and cancer mortality in depressed adults. These findings suggest that comprehensive dietary antioxidant intake may improve depressive symptoms and lower mortality risk among adults with depression.

Airway inflammation accelerates pulmonary exacerbations in cystic fibrosis

Airway inflammation underlies cystic fibrosis (CF) pulmonary exacerbations. In a prospective multicenter study of randomly selected, clinically stable adolescents and adults, we assessed relationships between 24 inflammation-associated molecules and the future occurrence of CF pulmonary exacerbation using proportional hazards models. We explored relationships for potential confounding or mediation by clinical factors and assessed sensitivities to treatments including CF transmembrane regulator (CFTR) protein synthesis modulators. Results from 114 participants, including seven on ivacaftor or lumacaftor-ivacaftor, representative of the US CF population during the study period, identified 10 biomarkers associated with future exacerbations mediated by percent predicted forced expiratory volume in 1 s. The findings were not sensitive to anti-inflammatory, antibiotic, and CFTR modulator treatments. The analyses suggest that combination treatments addressing RAGE-axis inflammation, protease-mediated injury, and oxidative stress might prevent pulmonary exacerbations. Our work may apply to other airway inflammatory diseases such as bronchiectasis and the acute respiratory distress syndrome.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

The beneficial effects of alpha-tocopherol on intestinal function and the expression of tight junction proteins in differentiated segments of the intestine in piglets

Alpha (α)-tocopherol is a major component of dietary vitamin E. Despite being one of the most widely used food supplements in both animals and humans, its role in intestinal functions remains unknown. We were able to examine and accurately demonstrate its permeability effect in vitro and its differentiated effect on tight junction expression in different segments of the intestine in vivo using cultured intestinal porcine epithelial cell line (IPEC-J2) and piglets. A cultured IPEC-J2 demonstrated that α-tocopherol upregulated the expression of tight junction proteins and improved their integrity, with a maximum effect at concentrations ranging from 20 to 40 μmol/L. In vivo data from weaned pigs fed different doses of α-tocopherol for 2 weeks revealed that α-tocopherol effectively increases the expression of tight junction proteins in all sections of the intestinal mucosa, with the highest effect on the duodenum at an optimum dose of 20-50 mg/kg. In contrast, α-tocopherol did not affect intestinal inflammation. These findings suggest that α-tocopherol maintains intestinal integrity and increases the expression of tight junction proteins both in vitro and in vivo.

Virtual Drug Repositioning as a Tool to Identify Natural Small Molecules That Synergize with Lumacaftor in F508del-CFTR Binding and Rescuing

Cystic fibrosis is a hereditary disease mainly caused by the deletion of the Phe 508 (F508del) of the cystic fibrosis transmembrane conductance regulator (CFTR) protein that is thus withheld in the endoplasmic reticulum and rapidly degraded by the ubiquitin/proteasome system. Cystic fibrosis remains a potentially fatal disease, but it has become treatable as a chronic condition due to some CFTR-rescuing drugs that, when used in combination, increase in their therapeutic effect due to a synergic action. Also, dietary supplementation of natural compounds in combination with approved drugs could represent a promising strategy to further alleviate cystic fibrosis symptoms. On these bases, we screened by in silico drug repositioning 846 small synthetic or natural compounds from the AIFA database to evaluate their capacity to interact with the highly druggable lumacaftor binding site of F508del-CFTR. Among the identified hits, nicotinamide (NAM) was predicted to accommodate into the lumacaftor binding region of F508del-CFTR without competing against the drug but rather stabilizing its binding. The effective capacity of NAM to bind F508del-CFTR in a lumacaftor-uncompetitive manner was then validated experimentally by surface plasmon resonance analysis. Finally, the capacity of NAM to synergize with lumacaftor increasing its CFTR-rescuing activity was demonstrated in cell-based assays. This study suggests the possible identification of natural small molecules devoid of side effects and endowed with the capacity to synergize with drugs currently employed for the treatment of cystic fibrosis, which hopefully will increase the therapeutic efficacy with lower doses.

The landscape of potential health benefits of carotenoids as natural supportive therapeutics in protecting against Coronavirus infection

The Coronavirus Disease-2019 (COVID-19) pandemic urges researching possibilities for prevention and management of the effects of the virus. Carotenoids are natural phytochemicals of anti-oxidant, anti-inflammatory and immunomodulatory properties and may exert potential in aiding in combatting the pandemic. This review presents the direct and indirect evidence of the health benefits of carotenoids and derivatives based on in vitro and in vivo studies, human clinical trials and epidemiological studies and proposes possible mechanisms of action via which carotenoids may have the capacity to protect against COVID-19 effects. The current evidence provides a rationale for considering carotenoids as natural supportive nutrients via antioxidant activities, including scavenging lipid-soluble radicals, reducing hypoxia-associated superoxide by activating antioxidant enzymes, or suppressing enzymes that produce reactive oxygen species (ROS). Carotenoids may regulate COVID-19 induced over-production of pro-inflammatory cytokines, chemokines, pro-inflammatory enzymes and adhesion molecules by nuclear factor kappa B (NF-κB), renin-angiotensin-aldosterone system (RAS) and interleukins-6- Janus kinase-signal transducer and activator of transcription (IL-6-JAK/STAT) pathways and suppress the polarization of pro-inflammatory M1 macrophage. Moreover, carotenoids may modulate the peroxisome proliferator-activated receptors γ by acting as agonists to alleviate COVID-19 symptoms. They also may potentially block the cellular receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human angiotensin-converting enzyme 2 (ACE2). These activities may reduce the severity of COVID-19 and flu-like diseases. Thus, carotenoid supplementation may aid in combatting the pandemic, as well as seasonal flu. However, further in vitro, in vivo and in particular long-term clinical trials in COVID-19 patients are needed to evaluate this hypothesis.

α-Tocopherol Pharmacokinetics in Adults with Cystic Fibrosis: Benefits of Supplemental Vitamin C Administration

BACKGROUND

Numerous abnormalities in cystic fibrosis (CF) could influence tocopherol absorption, transportation, storage, metabolism and excretion. We hypothesized that the oxidative distress due to inflammation in CF increases vitamin E utilization, which could be positively influenced by supplemental vitamin C administration.

METHODS

Immediately before and after receiving vitamin C (500 mg) twice daily for 3.5 weeks, adult CF patients (n = 6) with moderately advanced respiratory tract (RT) disease consumed a standardized breakfast with 30% fat and a capsule containing 50 mg each hexadeuterium (d₆)-α- and dideuterium (d₂)-γ-tocopheryl acetates. Blood samples were taken frequently up to 72 h; plasma tocopherol pharmacokinetics were determined. During both trials, d₆-α- and d₂-γ-tocopherols were similarly absorbed and reached similar maximal plasma concentrations ~18-20 h. As predicted, during vitamin C supplementation, the rates of plasma d₆-α-tocopherol decline were significantly slower.

CONCLUSIONS

The vitamin C-induced decrease in the plasma disappearance rate of α-tocopherol suggests that vitamin C recycled α-tocopherol, thereby augmenting its concentrations. We conclude that some attention should be paid to plasma ascorbic acid concentrations in CF patients, particularly to those individuals with more advanced RT inflammatory disease and including those with severe exacerbations.

Update on the management of vitamins and minerals in cystic fibrosis

Advancements in respiratory and nutrition management have significantly improved the survival of patients with cystic fibrosis (CF). With the availability of several nutrition interventions such as oral/enteral nutrition supplements, enteric‐coated pancreatic enzymes, and water‐miscible CF‐specific vitamin supplements, frank vitamin deficiencies—with the exception of vitamin D—are rarely encountered in current clinical practice. Whereas they were previously considered as micronutrients, our current understanding of fat‐soluble vitamins and minerals as antioxidants, immunomodulators, and disease biomarkers has been evolving. The impact of highly effective modulators on the micronutrient status of patients with CF remains elusive. This narrative review focuses on the updates on the management of fat‐soluble vitamins and other micronutrients in CF in the current era and identifies the gaps in our knowledge.

Cystic Fibrosis and Oxidative Stress: The Role of CFTR

There is substantial evidence in the literature that patients with cystic fibrosis (CF) have higher oxidative stress than patients with other diseases or healthy subjects. This results in an increase in reactive oxygen species (ROS) and in a deficit of antioxidant molecules and plays a fundamental role in the progression of chronic lung damage. Although it is known that recurrent infection–inflammation cycles in CF patients generate a highly oxidative environment, numerous clinical and preclinical studies suggest that the airways of a patient with CF present an inherently abnormal proinflammatory milieu due to elevated oxidative stress and abnormal lipid metabolism even before they become infected. This could be directly related to cystic fibrosis transmembrane conductance regulator (CFTR) deficiency, which appears to produce a redox imbalance in epithelial cells and extracellular fluids. This review aims to summarize the main mechanism by which CFTR deficiency is intrinsically responsible for the proinflammatory environment that characterizes the lung of a patient with CF.

The Use of Thiocyanate Formulations to Create Manganese Porphyrin Antioxidants That Supplement Innate Immunity

The innate immune response to infection results in inflammation and oxidative damage, creating a paradox where most anti-inflammatory and antioxidant therapies can further suppress an already inadequate immune response. We have previously reported the beneficial effects of the exogenous supplementation of innate immunity with small pseudohalide thiocyanate (⁻SCN) in a mouse model of a cystic fibrosis (CF) lung infection and inflammation. The object of this study was to evaluate the use of ⁻SCN as a counter anion for cationic manganese porphyrin (MnP) catalytic antioxidants, which could increase the parent compound’s antioxidant spectrum against hypohalous acids while supplementing innate immunity. The antioxidant activities of the parent compound were examined, as its chloride salt was compared with the ⁻SCN-anion exchanged compound, (MnP(SCN) versus MnP(Cl)). We measured the superoxide dismutase activity spectrophotometrically and performed hydrogen peroxide scavenging using oxygen and hydrogen peroxide electrodes. Peroxidase activity was measured using an amplex red assay. The inhibition of lipid peroxidation was assessed using a thiobarbituric acid reactive species (TBARS) assay. The effects of the MnP compounds on macrophage phagocytosis were assessed by flow cytometry. The abilities of the MnP(Cl) formulations to protect human bronchiolar epithelial cells against hypochlorite (HOCl) and glycine chloramine versus their MnP(SCN) formulations were assessed using a cell viability assay. We found that anions exchanging out the chloride for ⁻SCN improved the cellular bioavailability but did not adversely affect the cell viability or phagocytosis and that they switched hydrogen-peroxide scavenging from a dismutation reaction to a peroxidase reaction. In addition, the ⁻SCN formulations improved the ability of MnPs to protect human bronchiolar epithelial cells against hypochlorous acid (HOCl) and glycine chloramine toxicity. These novel types of antioxidants may be more beneficial in treating lung disease that is associated with chronic infections or acute infectious exacerbations.

Links between Disease Severity, Bacterial Infections and Oxidative Stress in Cystic Fibrosis

Cystic fibrosis (CF) is one of the most common, yet fatal genetic diseases in Caucasians. The presence of a defective CF transmembrane conductance regulator and the massive neutrophils influx into the airways contribute to an imbalance in epithelial cell processes and extracellular fluids and lead to excessive production of reactive oxygen species and intensification of oxidative stress. The study included 16 controls and 42 participants with CF aged 10 to 38. The products of protein oxidation, total antioxidant capacity (TAC) and markers of lipid peroxidation were estimated in the serum of the subjects. Furthermore, we compared the level of oxidative stress in patients with CF according to the severity of disease and type of bacterial infection. Thiol groups and serum TAC decreased significantly in patients with CF (p < 0.05). Elevated levels of 3-nitrotyrosine, malondialdehyde and 8-isoprostane were observed in CF subjects (p < 0.05). Furthermore, as the severity of the disease increased, there was a decrease in the thiol groups and TAC levels, as well as an increase in the concentration of 3-nitrotyrosine and 8-isoprostane. CF participants infected with Pseudomonas aeruginosa had elevated 3-nitrotyrosine concentration levels (p < 0.05), while those infected with Staphylococcus aureus noted a decrease in thiol groups (p < 0.05). Elevated levels of oxidative stress markers were found in the serum of CF patients. Furthermore, oxidative stress progressively increased over the years and along with the severity of the disease. The presence of bacterial infection with P. aeruginosa or S. aureus had a slight effect on oxidative stress, while co-infection by two species did not affect the level of oxidative stress.

Antifibrotic effect of brown algae-derived fucoidans on osteoarthritic fibroblast-like synoviocytes

Synovial fibrosis is a pathological process which contributes to joint pain and stiffness in several musculoskeletal disorders. Fucoidans, sulfated polysaccharides found in brown algae, have recently emerged as promising therapeutic agents. Despite the increasing amount of evidence suggesting the protective role of fucoidans in different experimental approaches of human fibrotic disorders, the effect of these sulfated polysaccharides on synovial fibrosis has not been investigated yet. By an in vitro experimental approach in fibroblast-like synoviocytes, we detected that fucoidans inhibit their differentiation into myofibroblasts with tumor cell-like characteristics and restore apoptosis. Composition and structure of fucoidan appear to be critical for the detected activity. Furthermore, protective effects of these sulfated polysaccharides are mediated by upregulation of nitric oxide production and modulation of TGF-β/smad pathway. Altogether, our results support the use of fucoidans as therapeutic compounds in the treatment of the fibrotic processes involved in rheumatic pathologies.

Brazilian Guidelines for Nutrition in Cystic Fibrosis

OBJECTIVE

To develop a scientific consensus on nutrition in cystic fibrosis.

METHODS

Sixteen coordinators elaborated relevant questions on nutritional therapy in cystic fibrosis, which were divided into six sections: nutritional assessment, nutritional recommendations, nutritional intervention, dietary counseling, special situations and enzyme replacement, and gastrointestinal manifestations. Two to three specialists in the field were responsible for each section and obtaining answers formulated based on standardized bibliographic searches. The available literature was searched in the PubMed®/MEDLINE database, after training and standardization of search strategies, to write the best level of evidence for the questions elaborated. Issues related to disagreement were discussed until a consensus was reached among specialists, based on the current scientific literature.

RESULTS

Forty-two questions were prepared and objectively answered, resulting in a consensus of nutritional therapy in cystic fibrosis.

CONCLUSION

This work enabled establishing a scientific consensus for nutritional treatment of cystic fibrosis patients.

An intervention to support adherence to inhaled medication in adults with cystic fibrosis: the ACtiF research programme including RCT

Background

People with cystic fibrosis frequently have low levels of adherence to inhaled medications.

Objectives

The objectives were to develop and evaluate an intervention for adults with cystic fibrosis to improve adherence to their inhaled medication.

Design

We used agile software methods to develop an online platform. We used mixed methods to develop a behaviour change intervention for delivery by an interventionist. These were integrated to become the CFHealthHub intervention. We undertook a feasibility study consisting of a pilot randomised controlled trial and process evaluation in two cystic fibrosis centres. We evaluated the intervention using an open-label, parallel-group randomised controlled trial with usual care as the control. Participants were randomised in a 1 : 1 ratio to intervention or usual care. Usual care consisted of clinic visits every 3 months. We undertook a process evaluation alongside the randomised controlled trial, including a fidelity study, a qualitative interview study and a mediation analysis. We undertook a health economic analysis using both a within-trial and model-based analysis.

Setting

The randomised controlled trial took place in 19 UK cystic fibrosis centres.

Participants

Participants were people aged ≥ 16 years with cystic fibrosis, on the cystic fibrosis registry, not post lung transplant or on the active transplant list, who were able to consent and not using dry-powder inhalers.

Intervention

People with cystic fibrosis used a nebuliser with electronic monitoring capabilities. This transferred data automatically to a digital platform. People with cystic fibrosis and clinicians could monitor adherence using these data, including through a mobile application (app). CFHealthHub displayed graphs of adherence data as well as educational and problem-solving information. A trained interventionist helped people with cystic fibrosis to address their adherence.

Main outcome measures

Randomised controlled trial – adjusted incidence rate ratio of pulmonary exacerbations meeting the modified Fuchs criteria over a 12-month follow-up period (primary outcome); change in percentage adherence; and per cent predicted forced expiratory volume in 1 second (key secondary outcomes). Process evaluation – percentage fidelity to intervention delivery, and participant and interventionist perceptions of the intervention. Economic modelling – incremental cost per quality-adjusted life-year gained.

Results

Randomised controlled trial – 608 participants were randomised to the intervention (n = 305) or usual care (n = 303). To our knowledge, this was the largest randomised controlled trial in cystic fibrosis undertaken in the UK. The adjusted rate of exacerbations per year (primary outcome) was 1.63 in the intervention and 1.77 in the usual-care arm (incidence rate ratio 0.96, 95% confidence interval 0.83 to 1.12; p = 0.638) after adjustment for covariates. The adjusted difference in mean weekly normative adherence was 9.5% (95% confidence interval 8.6% to 10.4%) across 1 year, favouring the intervention. Adjusted mean difference in forced expiratory volume in 1 second (per cent) predicted at 12 months was 1.4% (95% confidence interval –0.2% to 3.0%). No adverse events were related to the intervention. Process evaluation – fidelity of intervention delivery was high, the intervention was acceptable to people with cystic fibrosis, participants engaged with the intervention [287/305 (94%) attended the first intervention visit], expected mechanisms of action were identified and contextual factors varied between randomised controlled trial sites. Qualitative interviews with 22 people with cystic fibrosis and 26 interventionists identified that people with cystic fibrosis welcomed the objective adherence data as proof of actions to self and others, and valued the relationship that they built with the interventionists. Economic modelling – the within-trial analysis suggests that the intervention generated 0.01 additional quality-adjusted life-years at an additional cost of £865.91 per patient, leading to an incremental cost-effectiveness ratio of £71,136 per quality-adjusted life-year gained. This should be interpreted with caution owing to the short time horizon. The health economic model suggests that the intervention is expected to generate 0.17 additional quality-adjusted life-years and cost savings of £1790 over a lifetime (70-year) horizon; hence, the intervention is expected to dominate usual care. Assuming a willingness-to-pay threshold of £20,000 per quality-adjusted life-year gained, the probability that the intervention generates more net benefit than usual care is 0.89. The model results are dependent on assumptions regarding the duration over which costs and effects of the intervention apply, the impact of the intervention on forced expiratory volume in 1 second (per cent) predicted and the relationship between increased adherence and drug-prescribing levels.

Limitations

Number of exacerbations is a sensitive and valid measure of clinical change used in many trials. However, data collection of this outcome in this context was challenging and could have been subject to bias. It was not possible to measure baseline adherence accurately. It was not possible to quantify the impact of the intervention on the number of packs of medicines prescribed.

Conclusions

We developed a feasible and acceptable intervention that was delivered to fidelity in the randomised controlled trial. We observed no statistically significant difference in the primary outcome of exacerbation rates over 12 months. We observed an increase in normative adherence levels in a disease where adherence levels are low. The magnitude of the increase in adherence may not have been large enough to affect exacerbations.

Future work

Given the non-significant difference in the primary outcome, further research is required to explore why an increase in objective normative adherence did not reduce exacerbations and to develop interventions that reduce exacerbations.

Trial registration

Work package 3.1: Current Controlled Trials ISRCTN13076797. Work packages 3.2 and 3.3: Current Controlled Trials ISRCTN55504164.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 11. See the NIHR Journals Library website for further project information.

Case report: Three adult brothers with cystic fibrosis (delF508-delF508) maintain unusually preserved clinical profile in the absence of standard CF care

We present three cases in this report. Three adult brothers, homozygous for the delF508 cystic fibrosis mutation, have maintained an unusually preserved clinical condition even though they did not attend a CF Clinic during their childhood, do not attend a CF Clinic now, and do not follow standard CF care guidelines. The brothers use an alternative CF treatment regimen on which they have maintained normal lung function, height/weight, and bloodwork, and they utilize less than half the recommended dosage of pancreatic enzymes. The brothers culture only methicillin-sensitive Staphylococcus aureus, and have never cultured any other bacteria. Highly effective modulator therapies, such as elexacaftor/tezacaftor/ivacaftor, do not substantially reduce infection and inflammation in vivo in CF patients, and thus these three case reports are of special note in terms of suggesting adjunct therapeutic approaches. Finally, these three cases also raise important questions about standard CF care guidelines.

Oxidative Stress and Endoplasmic Reticulum Stress in Rare Respiratory Diseases

Several studies have shown that some rare respiratory diseases, such as alpha-1 antitrypsin deficiency (AATD), idiopathic pulmonary fibrosis (IPF), cystic fibrosis (CF), and primary ciliary dyskinesia (PCD) present oxidative stress (OS) and endoplasmic reticulum (ER) stress. Their involvement in these pathologies and the use of antioxidants as therapeutic agents to minimize the effects of OS are discussed in this review.

Airway Redox Homeostasis and Inflammation Gone Awry: From Molecular Pathogenesis to Emerging Therapeutics in Respiratory Pathology

As aerobic organisms, we are continuously and throughout our lifetime subjected to an oxidizing atmosphere and, most often, to environmental threats. The lung is the internal organ most highly exposed to this milieu. Therefore, it has evolved to confront both oxidative stress induced by reactive oxygen species (ROS) and a variety of pollutants, pathogens, and allergens that promote inflammation and can harm the airways to different degrees. Indeed, an excess of ROS, generated intrinsically or from external sources, can imprint direct damage to key structural cell components (nucleic acids, sugars, lipids, and proteins) and indirectly perturb ROS-mediated signaling in lung epithelia, impairing its homeostasis. These early events complemented with efficient recognition of pathogen- or damage-associated recognition patterns by the airway resident cells alert the immune system, which mounts an inflammatory response to remove the hazards, including collateral dead cells and cellular debris, in an attempt to return to homeostatic conditions. Thus, any major or chronic dysregulation of the redox balance, the air-liquid interface, or defects in epithelial proteins impairing mucociliary clearance or other defense systems may lead to airway damage. Here, we review our understanding of the key role of oxidative stress and inflammation in respiratory pathology, and extensively report current and future trends in antioxidant and anti-inflammatory treatments focusing on the following major acute and chronic lung diseases: acute lung injury/respiratory distress syndrome, asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, and cystic fibrosis.

Cystic Fibrosis and Genotype-Dependent Therapy: Is There a Need for a Sex-Specific Therapy?

Cystic fibrosis (CF) is an autosomal recessive genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulation (CFTR) anion channel. Loss of CFTR protein and/or function disrupts chloride, bicarbonate, and fluid transport and also impacts epithelial sodium transport. Such altered ion and fluid transport produces mucus obstruction, inflammation, pulmonary infection, and damage to multiple organs. Although an autosomal disease, it is apparent that gender differences in life expectancy and quality of life do exist. Conventionally established therapies have treated the downstream sequelae of CFTR dysfunction and have led to a steady increase in life expectancy. Physicians now have access to medications that treat the basic defect in CF, in the form of CFTR modulators. These drugs target the trafficking and/or function of CFTR to improve clinical outcomes for patients. This review summarizes the science behind CFTR modulators and shows how these drugs have dramatically changed how patients with CF are treated. Surprisingly, although the drug target(s) are identical in males and females, CF females seem to display a greater improvement than their male counterparts.

Antibiotic adjuvant therapy for pulmonary infection in cystic fibrosis

BACKGROUND

Cystic fibrosis is a multi-system disease characterised by the production of thick secretions causing recurrent pulmonary infection, often with unusual bacteria. This leads to lung destruction and eventually death through respiratory failure. There are no antibiotics in development that exert a new mode of action and many of the current antibiotics are ineffective in eradicating the bacteria once chronic infection is established. Antibiotic adjuvants - therapies that act by rendering the organism more susceptible to attack by antibiotics or the host immune system, by rendering it less virulent or killing it by other means, would be a significant therapeutic advance. This is an update of a previously published review.

OBJECTIVES

To determine if antibiotic adjuvants improve clinical and microbiological outcome of pulmonary infection in people with cystic fibrosis.

SEARCH METHODS

We searched the Cystic Fibrosis Trials Register which is compiled from database searches, hand searches of appropriate journals and conference proceedings. Date of most recent search: 16 January 2020. We also searched MEDLINE (all years) on 14 February 2019 and ongoing trials registers on 06 April 2020.

SELECTION CRITERIA

Randomised controlled trials and quasi-randomised controlled trials of a therapy exerting an antibiotic adjuvant mechanism of action compared to placebo or no therapy for people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two of the authors independently assessed and extracted data from identified trials.

MAIN RESULTS

We identified 42 trials of which eight (350 participants) that examined antibiotic adjuvant therapies are included. Two further trials are ongoing and five are awaiting classification. The included trials assessed β-carotene (one trial, 24 participants), garlic (one trial, 34 participants), KB001-A (a monoclonal antibody) (two trials, 196 participants), nitric oxide (two trials, 30 participants) and zinc supplementation (two trials, 66 participants). The zinc trials recruited children only, whereas the remaining trials recruited both adults and children. Three trials were located in Europe, one in Asia and four in the USA. Three of the interventions measured our primary outcome of pulmonary exacerbations (β-carotene, mean difference (MD) -8.00 (95% confidence interval (CI) -18.78 to 2.78); KB001-A, risk ratio (RR) 0.25 (95% CI 0.03 to 2.40); zinc supplementation, RR 1.85 (95% CI 0.65 to 5.26). β-carotene and KB001-A may make little or no difference to the number of exacerbations experienced (low-quality evidence); whereas, given the moderate-quality evidence we found that zinc probably makes no difference to this outcome. Respiratory function was measured in all of the included trials. β-carotene and nitric oxide may make little or no difference to forced expiratory volume in one second (FEV₁) (low-quality evidence), whilst garlic probably makes little or no difference to FEV₁ (moderate-quality evidence). It is uncertain whether zinc or KB001-A improve FEV₁ as the certainty of this evidence is very low. Few adverse events were seen across all of the different interventions and the adverse events that were reported were mild or not treatment-related (quality of the evidence ranged from very low to moderate). One of the trials (169 participants) comparing KB001-A and placebo, reported on the time to the next course of antibiotics; results showed there is probably no difference between groups, HR 1.00 (95% CI 0.69 to 1.45) (moderate-quality evidence). Quality of life was only reported in the two KB001-A trials, which demonstrated that there may be little or no difference between KB001-A and placebo (low-quality evidence). Sputum microbiology was measured and reported for the trials of KB001-A and nitric oxide (four trials). There was very low-quality evidence of a numerical reduction in Pseudomonas aeruginosa density with KB001-A, but it was not significant. The two trials looking at the effects of nitric oxide reported significant reductions in Staphylococcus aureus and near-significant reductions in Pseudomonas aeruginosa, but the quality of this evidence is again very low.

AUTHORS' CONCLUSIONS

We could not identify an antibiotic adjuvant therapy that we could recommend for treating of lung infection in people with cystic fibrosis. The emergence of increasingly resistant bacteria makes the reliance on antibiotics alone challenging for cystic fibrosis teams. There is a need to explore alternative strategies, such as the use of adjuvant therapies. Further research is required to provide future therapeutic options.

Evaluation of airway and circulating inflammatory biomarkers for cystic fibrosis drug development

INTRODUCTION

Biomarkers of inflammation in blood and sputum can play a critical role in anti-inflammatory drug development in cystic fibrosis (CF). The objectives of this analysis were to examine relationships between airway and systemic measurements of inflammation, associations between inflammatory biomarkers and FEV₁, differences in airway and systemic inflammation by baseline covariates, reproducibility of serum biomarkers, and to assess the effects of freezing and delayed processing on sputum analyte measurements.

METHODS

We analyzed baseline and serial concentrations of inflammatory markers in blood and induced sputum collected from individuals with CF ages 10 years and older who participated in a multicenter clinical trial.

RESULTS

Among circulating biomarkers, serum high sensitivity C-reactive protein (hsCRP) and serum amyloid A (SAA) correlated most strongly with each other (r_s = 0.85). Comparing sputum-based inflammation measurements, sputum neutrophil elastase and myeloperoxidase (MPO) were the most highly correlated (r_s = 0.88). Markers most strongly correlated with ppFEV₁ were serum hsCRP (r_s = -0.55), SAA (r_s =-0.58), and sputum neutrophil elastase (r_s = -0.53). Within-subject standard deviation was consistently lower than between-subject standard deviation for all serum biomarkers. Serum calprotectin and MPO had the highest ratio of between-to-within subject variability. Freezing and delayed sputum processing were not associated with significant differences in measurements of sputum neutrophil elastase, IL-1β, or MPO.

CONCLUSIONS

Among the biomarkers analyzed, serum hsCRP and sputum neutrophil elastase are promising candidates to include in CF anti-inflammatory clinical trials to avoid redundancy, minimize variation, and serve as correlates of lung disease severity and change.

Nonpharmacological treatment for patients with nontuberculous mycobacterial lung disease

Patients with nontuberculous mycobacterial lung disease (NTM-LD) often have significant exercise intolerance and poorer health-related quality of life (HRQL). The goals of treatment for NTM-LD should include reducing the severity of symptoms, improving HRQL, and reducing acute exacerbations. Nonpharmacological treatment, including pulmonary rehabilitation program and optimal nutritional strategy, should be one part of treatment for NTM-LD. A pulmonary rehabilitation (PR) program can comprise education, airway clearance techniques instruction, exercise training program, and inspiratory muscle training (IMT). Airway clearance techniques can improve the volume of sputum expectorated, cough symptom, breathlessness, and HRQL. Exercise training can improve exercise capacity and HRQL, and reduce acute exacerbations and dyspnea. Clinical benefits of IMT remain controversial but high-intensity IMT has been shown to be effective in increasing respiratory muscle strength with concurrent improvement of HRQL and exercise capacity. Body weight and muscle mass loss are common in patients with NTM-LD. An adequate protein and caloric diet combined with antioxidant nutrients might be the most appropriate dietary strategy. Comprehensive treatment for NTM-LD should include the combination of both pharmacological and nonpharmacological treatments. The management programs should be tailored to the individual's condition.

Antioxidant Micronutrients and Essential Fatty Acids Supplementation on Cystic Fibrosis Outcomes: A Systematic Review

BACKGROUND

Antioxidant micronutrients and essential fatty acids supplementation intake appears to have a protective effect in some diseases such as cardiovascular disease, cancer, and asthma.

OBJECTIVE

The aim of this study was to perform a systematic review to evaluate the effects of these nutrients on nutritional and clinical outcomes of patients with cystic fibrosis (CF).

METHODS

This is a systematic review of randomized clinical trials (RCTs) in CF. MEDLINE (via PubMed), Embase, and Scopus databases were searched for RCTs published from 1948 through February 2019. Two investigators independently reviewed the titles and abstracts and then extracted the data from the included studies using a standardized predesigned form. Two reviewers independently performed the quality assessment of the RCTs according to the Cochrane risk of bias tools.

RESULTS

A total of 4,792 studies were identified, and 23 were eligible (8 antioxidant micronutrient and 15 essential fatty acids). The interventions found were beta-carotene, zinc, magnesium, multivitamin, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), linoleic acid and lipid matrix with choline supplementation. A significant improvement was observed in: (a) pulmonary function with magnesium (n=1) and essential fatty acids (n=2) supplementation; (b) less pulmonary exacerbations with beta-carotene (n=1), zinc (n=1), antioxidant-enriched multivitamin (n=1) and essential fatty acids (n=2) supplementation. One study with antioxidant-enriched multivitamin and four studies with EPA/DHA supplementation reported significant reductions in inflammatory markers. Nutritional status was not modified by antioxidants supplementation in any of the studies, while in five studies there was an improvement with fatty acids supplementation. The risk of bias of the majority of the parallel studies was high.

CONCLUSIONS

The benefits of antioxidants or DHA/EPA supplementation for CF, although observed in some studies, are not consistent enough to recommend routine use of these supplements. The mechanisms of action of these nutrients, dose levels and timing should be further explored in future studies.

Targeting airway inflammation in cystic fibrosis

Introduction: The major cause of morbidity and mortality in patients with cystic fibrosis (CF) is lung disease. Inflammation in the CF airways occurs from a young age and contributes significantly to disease progression and shortened life expectancy. Areas covered: In this review, we discuss the key immune cells involved in airway inflammation in CF, the contribution of the intrinsic genetic defect to the CF inflammatory phenotype, and anti-inflammatory strategies designed to overcome what is a critical factor in the pathogenesis of CF lung disease. Review of the literature was carried out using the MEDLINE (from 1975 to 2018), Google Scholar and The Cochrane Library databases. Expert opinion: Therapeutic interventions specifically targeting the defective CF transmembrane conductance regulator (CFTR) protein have changed the clinical landscape and significantly improved the outlook for CF. As survival estimates for people with CF increase, long-term management has become an important focus, with an increased need for therapies targeted at specific elements of inflammation, to complement CFTR modulator therapies.

Antioxidant supplementation for lung disease in cystic fibrosis

BACKGROUND

Airway infection leads to progressive damage of the lungs in cystic fibrosis (CF) and oxidative stress has been implicated in the etiology. Supplementation of antioxidant micronutrients (vitamin E, vitamin C, beta-carotene and selenium) or N-acetylcysteine (NAC) as a source of glutathione, may therefore potentially help maintain an oxidant-antioxidant balance. Glutathione or NAC can also be inhaled and if administered in this way can also have a mucolytic effect besides the antioxidant effect. Current literature suggests a relationship between oxidative status and lung function. This is an update of a previously published review.

OBJECTIVES

To synthesise existing knowledge on the effect of antioxidants such as vitamin C, vitamin E, beta-carotene, selenium and glutathione (or NAC as precursor of glutathione) on lung function through inflammatory and oxidative stress markers in people with CF.

SEARCH METHODS

The Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register and PubMed were searched using detailed search strategies. We contacted authors of included studies and checked reference lists of these studies for additional, potentially relevant studies. We also searched online trials registries.Last search of Cystic Fibrosis Trials Register: 08 January 2019.

SELECTION CRITERIA

Randomised and quasi-randomised controlled studies comparing antioxidants as listed above (individually or in combination) in more than a single administration to placebo or standard care in people with CF.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies, extracted data and assessed the risk of bias in the included studies. We contacted study investigators to obtain missing information. If meta-analysed, studies were subgrouped according to supplement, method of administration and the duration of supplementation. We assessed the quality of the evidence using GRADE.

MAIN RESULTS

One quasi-randomised and 19 randomised controlled studies (924 children and adults) were included; 16 studies (n = 639) analysed oral antioxidant supplementation and four analysed inhaled supplements (n = 285). Only one of the 20 included studies was judged to be free of bias.Oral supplements versus controlThe change from baseline in forced expiratory volume in one second (FEV₁) % predicted at three months and six months was only reported for the comparison of NAC to control. Four studies (125 participants) reported at three months; we are uncertain whether NAC improved FEV₁ % predicted as the quality of the evidence was very low, mean difference (MD) 2.83% (95% confidence interval (CI) -2.16 to 7.83). However, at six months two studies (109 participants) showed that NAC probably increased FEV₁ % predicted from baseline (moderate-quality evidence), MD 4.38% (95% CI 0.89 to 7.87). A study of a combined vitamin and selenium supplement (46 participants) reported a greater change from baseline in FEV₁ % predicted in the control group at two months, MD -4.30% (95% CI -5.64 to -2.96). One study (61 participants) found that NAC probably makes little or no difference in the change from baseline in quality of life (QoL) at six months (moderate-quality evidence), standardised mean difference (SMD) -0.03 (95% CI -0.53 to 0.47), but the two-month combined vitamin and selenium study reported a small difference in QoL in favour of the control group, SMD -0.66 (95% CI -1.26 to -0.07). The NAC study reported on the change from baseline in body mass index (BMI) (62 participants) and similarly found that NAC probably made no difference between groups (moderate-quality evidence). One study (69 participants) found that a mixed vitamin and mineral supplement may lead to a slightly lower risk of pulmonary exacerbation at six months than a multivitamin supplement (low-quality evidence). Nine studies (366 participants) provided information on adverse events, but did not find any clear and consistent evidence of differences between treatment or control groups with the quality of the evidence ranging from low to moderate. Studies of β-carotene and vitamin E consistently reported greater plasma levels of the respective antioxidants.Inhaled supplements versus controlTwo studies (258 participants) showed inhaled glutathione probably improves FEV₁ % predicted at three months, MD 3.50% (95% CI 1.38 to 5.62), but not at six months compared to placebo, MD 2.30% (95% CI -0.12 to 4.71) (moderate-quality evidence). The same studies additionally reported an improvement in FEV₁ L in the treated group compared to placebo at both three and six months. One study (153 participants) reported inhaled glutathione probably made little or no difference to the change in QoL from baseline, MD 0.80 (95% CI -1.63 to 3.23) (moderate-quality evidence). No study reported on the change from baseline in BMI at six months, but one study (16 participants) reported at two months and a further study (105 participants) at 12 months; neither study found any difference at either time point. One study (153 participants) reported no difference in the time to the first pulmonary exacerbation at six months. Two studies (223 participants) reported treatment may make little or no difference in adverse events (low-quality evidence), a further study (153 participants) reported that the number of serious adverse events were similar across groups.

AUTHORS' CONCLUSIONS

With regards to micronutrients, there does not appear to be a positive treatment effect of antioxidant micronutrients on clinical end-points; however, oral supplementation with glutathione showed some benefit to lung function and nutritional status. Based on the available evidence, inhaled and oral glutathione appear to improve lung function, while oral administration decreases oxidative stress; however, due to the very intensive antibiotic treatment and other concurrent treatments that people with CF take, the beneficial effect of antioxidants remains difficult to assess in those with chronic infection without a very large population sample and a long-term study period. Further studies, especially in very young children, using outcome measures such as lung clearance index and the bronchiectasis scores derived from chest scans, with improved focus on study design variables (such as dose levels and timing), and elucidating clear biological pathways by which oxidative stress is involved in CF, are necessary before a firm conclusion regarding effects of antioxidants supplementation can be drawn. The benefit of antioxidants in people with CF who receive CFTR modulators therapies should also be assessed in the future.

Cystic fibrosis year in review 2018, part 2

Cystic fibrosis (CF) research and case reports were robust in the year 2018. This report summarizes publications related the multisystem effects of CF, pulmonary exacerbations, new and expanded therapies other than cystic fibrosis transmembrane conductance regulator modulator studies, and patient-reported priorities and outcomes.

Challenges with optimizing nutrition in cystic fibrosis

Introduction. Optimizing nutrition remains the cornerstone of therapy for patients with cystic fibrosis (CF) since it is associated with better pulmonary function and survival. However, a significant proportion of patients still fail to achieve normal growth and nutritional status. Areas covered. This review describes the current challenges in providing effective nutritional therapy in CF with a focus on the current issues related to energy imbalance, dietary composition, adherence to nutritional recommendations, pancreatic enzyme replacement therapy, and the effects of modulators of the CF transmembrane conductance regulator. Expert opinion. CF is a multisystemic disease that requires a personalized nutritional approach with accurate evaluation of energy balance. There is an urgent need for evidence-based recommendations on the dietary composition, in consideration of the increasing prevalence of overweight, diabetes and the potential effects of fatty acids on inflammation and immune response. More research into new pancreatic enzyme formulations is also required.

Rapid therapeutic advances in CFTR modulator science

Cystic fibrosis (CF) is an autosomal recessive genetic disease caused by variants in the gene encoding the cystic fibrosis transmembrane conduction regulator (CFTR) protein. Loss of CFTR function disrupts chloride, bicarbonate and regulation of sodium transport, producing a cascade of mucus obstruction, inflammation, pulmonary infection, and ultimately damage in numerous organs. Established CF therapies treat the downstream consequences of CFTR dysfunction and have led to steady improvements in patient survival. A class of drugs termed CFTR modulators has recently entered the CF therapeutic landscape. These drugs differ fundamentally from prior therapies in that they aim to improve the function of disease-causing CFTR variants. This review summarizes the science behind CFTR modulators, including their targets, mechanism of action, clinical benefit, and future directions in the field. CFTR modulators have dramatically changed how CF is treated, validated CFTR as a therapeutic target, and opened the door to truly personalized therapies and treatment regimens.