Cell Stress. 2024 Apr 30;8:51-55. doi: 10.15698/cst2024.04.295. eCollection 2024.

ABSTRACT

In a recent issue in Nature Cell Biology, Sung Min Son et al. unveil a novel layer in the regulation of the mTORC1/autophagy axis by EP300 which can undergo nucleocytoplasmic shuttling in response to alterations in nutrient availability. The study highlights that, in Hutchinson-Gilford progeria syndrome, overabundant cytoplasmic EP300 results in mTORC1 hyperactivation and impaired autophagy, potentially contributing to premature and accelerated aging.

PMID:38800095 | PMC:PMC11118783 | DOI:10.15698/cst2024.04.295

bioRxiv [Preprint]. 2024 May 14:2024.05.10.593624. doi: 10.1101/2024.05.10.593624.

ABSTRACT

Dysregulated neutrophil recruitment drives many pulmonary diseases, but most preclinical screening methods are unsuited to evaluate pulmonary neutrophilia, limiting progress towards therapeutics. Namely, high throughput therapeutic screening systems typically exclude critical neutrophilic pathophysiology, including blood-to-lung recruitment, dysfunctional activation, and resulting impacts on the air-blood barrier. To meet the conflicting demands of physiological complexity and high throughput, we developed an assay of 96-well Leukocyte recruitment in an Air-Blood Barrier Array (L-ABBA-96) that enables in vivo -like neutrophil recruitment compatible with downstream phenotyping by automated flow cytometry. We modeled acute respiratory distress syndrome (ARDS) with neutrophil recruitment to 20 ng/mL epithelial-side interleukin 8 (IL-8) and found a dose dependent reduction in recruitment with physiologic doses of baricitinib, a JAK1/2 inhibitor recently FDA-approved for severe COVID-19 ARDS. Additionally, neutrophil recruitment to patient-derived cystic fibrosis sputum supernatant induced disease-mimetic recruitment and activation of healthy donor neutrophils and upregulated endothelial e-selectin. Compared to 24-well assays, the L-ABBA-96 reduces required patient sample volumes by 25 times per well and quadruples throughput per plate. Compared to microfluidic assays, the L-ABBA-96 recruits two orders of magnitude more neutrophils per well, enabling downstream flow cytometry and other standard biochemical assays. This novel pairing of high-throughput in vitro modeling of organ-level lung function with parallel high-throughput leukocyte phenotyping substantially advances opportunities for pathophysiological studies, personalized medicine, and drug testing applications.

PMID:38798413 | PMC:PMC11118313 | DOI:10.1101/2024.05.10.593624

Front Pediatr. 2024 May 10;12:1393193. doi: 10.3389/fped.2024.1393193. eCollection 2024.

ABSTRACT

Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations of the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). In 1949, it's been identified as a monogenic disease and was thought to primarily affect individuals of Northern European descent. It was the most prevalent autosomal recessive disease that shortens life. With the availability of multiple testing methodologies nowadays, there is a chance to create novel and enhanced treatment options. Even in the absence of a high sweat chloride test (SCT) result, the discovery of two causal mutations is diagnostic for cystic fibrosis (CF). For a CF diagnosis, however, at least two positive E sweat chloride tests are still required. In order to achieve early and active intervention to manage cystic fibrosis (CF) and its comorbidities, treatment regimens for pediatric patients should be evaluated, improved, and closely monitored. New developments in the treatment of cystic fibrosis (CF) have led to the development of medications derived from molecules that target the pathogenetic pathway of the illness. These options are very efficient and allow pediatric patients to receive individualized care. However, in order to better direct patient care and enhance patient outcomes, it is crucial to research uncommon CF mutations, which can provide crucial information about the prognosis of the disease and the relationships between genotype and phenotype. To ensure the success of creating novel, safer, and more efficient treatment approaches, a deeper understanding of the pathogeny of the illness is required. In the age of customized medicine, genetic research will be essential to improving patient care and quality of life for those with uncommon mutations.

PMID:38798310 | PMC:PMC11116730 | DOI:10.3389/fped.2024.1393193

Pulm Pharmacol Ther. 2024 May 24:102301. doi: 10.1016/j.pupt.2024.102301. Online ahead of print.

ABSTRACT

Elexacaftor, tezacaftor, ivacaftor (ETI) is a CFTR modulator combination approved for use in ∼90% of people with cystic fibrosis (pwCF) over 2 years old. While most pwCF tolerate this therapy well, some are intolerant to standard dosing, and others show little response. Clinical providers may adjust ETI dosing to combat these issues, but these adjustments are not well guided by pharmacokinetic evidence. Our post-approval study aimed to describe pharmacokinetic variability of ETI plasma concentrations in 15 participants who were administered a standard or reduced dose. ETI were quantified by LC-MS/MS in plasma samples taken prior to the morning dose. Results showed non-significant differences for each compound regardless dosing regimen and after dose equivalence normalization. The majority of participants in both dosing groups had concentrations expected to elicit clinical response to ETI therapy. These findings indicate that dose reduction may be a viable strategy to maintain clinical benefit while managing intolerance.

PMID:38797221 | DOI:10.1016/j.pupt.2024.102301

Curr Probl Pediatr Adolesc Health Care. 2024 May 25:101638. doi: 10.1016/j.cppeds.2024.101638. Online ahead of print.

NO ABSTRACT

PMID:38797571 | DOI:10.1016/j.cppeds.2024.101638

Plants (Basel). 2024 May 18;13(10):1412. doi: 10.3390/plants13101412.

ABSTRACT

Pseudomonas aeruginosa is an opportunistic pathogen that is especially dominant in people with cystic fibrosis; the drug resistance expressed by this pathogen and its capacity for adaptation poses a significant challenge to its treatment and control, thereby increasing morbidity and mortality rates globally. In this sense, the search for new treatment alternatives is imminent today, with products of plant origin being an excellent alternative for use. The objective of this research was to evaluate the antibacterial and antibiofilm potential and to explore the possible effect of ethanolic extracts from the wood and bark of Duguetia vallicola on the cell membrane. Microdilution assays showed the inhibition of bacterial growth by more than 50%, with the lowest concentration (62.5 μg/mL) of both extracts evaluated. Furthermore, we report the ability of both extracts to inhibit mature biofilms, with inhibition percentages between 48.4% and 93.7%. Intracellular material leakage experiments (260/280 nm), extracellular pH measurements, and fluorescence microscopy with acridine orange (AO) and ethidium bromide (EB) showed cell membrane damage. This indicates that the antibacterial action of ethanolic extracts of D. vallicola is associated with damage to the integrity of the cell membrane and consequent death of these pathogens. These results serve as a reference for future studies in establishing the mechanisms of action of these extracts.

PMID:38794482 | DOI:10.3390/plants13101412

Pharmaceutics. 2024 May 11;16(5):648. doi: 10.3390/pharmaceutics16050648.

ABSTRACT

Inhaled ciprofloxacin (CFX) has been investigated as a treatment for lower respiratory tract infections (LRTIs) associated with cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD), and bronchiectasis. The challenges in CFX effectiveness for LRTI treatment include poor aqueous solubility and therapy resistance. CFX dry powder for inhalation (DPI) formulations were well-tolerated, showing a remarkable decline in overall bacterial burden compared to a placebo in bronchiectasis patients. Recent research using an inhalable powder combining Pseudomonas phage PEV20 with CFX exhibited a substantial reduction in bacterial density in mouse lungs infected with clinical P. aeruginosa strains and reduced inflammation. Currently, studies suggest that elevated biosynthesis of fatty acids could serve as a potential biomarker for detecting CFX resistance in LRTIs. Furthermore, inhaled CFX has successfully addressed various challenges associated with traditional CFX, including the incapacity to eliminate the pathogen, the recurrence of colonization, and the development of resistance. However, further exploration is needed to address three key unresolved issues: identifying the right patient group, determining the optimal treatment duration, and accurately assessing the risk of antibiotic resistance, with additional multicenter randomized controlled trials suggested to tackle these challenges. Importantly, future investigations will focus on the effectiveness of CFX DPI in bronchiectasis and COPD, aiming to differentiate prognoses between these two conditions. This review underscores the importance of CFX inhalable formulations against LRTIs in preclinical and clinical sectors, their challenges, recent advancements, and future perspectives.

PMID:38794310 | DOI:10.3390/pharmaceutics16050648

Life (Basel). 2024 Apr 27;14(5):565. doi: 10.3390/life14050565.

ABSTRACT

Calcitonin gene-related peptide (CGRP) has long been implicated in both the physiology and pathophysiology of the respiratory tract. The objective of our study was to determine the serum concentration of alpha CGRP (αCGRP) in cystic fibrosis (CF) that arises from mutations in the gene responsible for encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Currently, there are not many data in the literature about the role of CGRP in CF. The serum level of αCGRP was estimated using the enzyme-linked immunosorbent assay among 64 patients with CF and 31 healthy controls. The αCGRP concentration in the CF group was 62.51 ± 15.45 pg/mL, while in the control group it was 47.43 ± 8.06 pg/mL (p < 0.001). We also compared the level of αCGRP in CF patients according to the type of CFTR mutation. Homozygotes for ΔF508 had higher αCGRP levels than heterozygotes (67.9 ± 10.2 vs. 54.5 ± 18.3 pg/mL, p < 0.01). The level of this neuropeptide was statistically higher in patients with severe disease than in those with mild CF (p = 0.003) when patients were divided into three groups by spirometry results. αCGRP concentration was not correlated with age, sex, clinical parameters, and pulmonary function test results in the study participants. The results of our study suggest a significant increase in the concentration of αCGRP in the serum of patients with CF compared to the control group. This observation opens interesting possibilities for understanding the role of αCGRP in the context of CF pathophysiology.

PMID:38792587 | DOI:10.3390/life14050565

J Clin Med. 2024 May 20;13(10):3013. doi: 10.3390/jcm13103013.

ABSTRACT

Background: Benralizumab has been shown to restore good control of severe eosinophilic asthma (SEA). Robust data on benralizumab effectiveness over periods longer than 2 years are scarce. Methods: This retrospective multicentric study was conducted on 108 Italian SEA patients treated with benralizumab for up to 36 months. Partial and complete clinical remission (CR) were assessed. Data were analyzed with descriptive statistics or using linear, logistic, and negative binomial mixed-effect regression models. Results: At 36 months, benralizumab reduced the exacerbation rate by 89% and increased the forced expiratory volume in 1 second (FEV1) (+440 mL at 36 months, p < 0.0001). Benralizumab improved asthma control as well as sinonasal symptoms in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP). Up to 93.33% of patients either reduced or discontinued OCS; benralizumab also decreased ICS use and other asthma medications. Overall, 84.31% of patients achieved partial or complete CR. Conclusions: Benralizumab improved asthma and sinonasal outcomes up to 36 months. These findings support the potential of benralizumab to induce CR, emphasizing its role as a disease-modifying anti-asthmatic drug for the management of SEA. Further research is warranted to expand these findings by minimizing data loss and assessing benralizumab's long-term safety.

PMID:38792553 | DOI:10.3390/jcm13103013

Int J Mol Sci. 2024 May 16;25(10):5416. doi: 10.3390/ijms25105416.

ABSTRACT

Previous omics research in patients with complex congenital heart disease and single-ventricle circulation (irrespective of the stage of palliative repair) revealed alterations in cardiac and systemic metabolism, inter alia abnormalities in energy metabolism, and inflammation, oxidative stress or endothelial dysfunction. We employed an affinity-proteomics approach focused on cell surface markers, cytokines, and chemokines in the serum of 20 adult Fontan patients with a good functioning systemic left ventricle, and we 20 matched controls to reveal any specific processes on a cellular level. Analysis of 349 proteins revealed 4 altered protein levels related to chronic inflammation, with elevated levels of syndecan-1 and glycophorin-A, as well as decreased levels of leukemia inhibitory factor and nerve growth factor-ß in Fontan patients compared to controls. All in all, this means that Fontan circulation carries specific physiological and metabolic instabilities, including chronic inflammation, oxidative stress imbalance, and consequently, possible damage to cell structure and alterations in translational pathways. A combination of proteomics-based biomarkers and the traditional biomarkers (uric acid, γGT, and cholesterol) performed best in classification (patient vs. control). A metabolism- and signaling-based approach may be helpful for a better understanding of Fontan (patho-)physiology. Syndecan-1, glycophorin-A, leukemia inhibitory factor, and nerve growth factor-ß, especially in combination with uric acid, γGT, and cholesterol, might be interesting candidate parameters to complement traditional diagnostic imaging tools and the determination of traditional biomarkers, yielding a better understanding of the development of comorbidities in Fontan patients, and they may play a future role in the identification of targets to mitigate inflammation and comorbidities in Fontan patients.

PMID:38791454 | DOI:10.3390/ijms25105416

Biomedicines. 2024 May 9;12(5):1047. doi: 10.3390/biomedicines12051047.

ABSTRACT

Different factors, not limited to the lung, influence the progression of ILDs. A "treatable trait" strategy was recently proposed for ILD patients as a precision model of care to improve outcomes. However, no data have been published so far on the prevalence of TTs in ILD. A prospective, observational, cohort study was conducted within the ILD Program at the IRCCS Humanitas Research Hospital (Milan, Italy) between November 2021 and November 2023. TTs were selected according to recent literature and assigned during multidisciplinary discussion (MDD) to one of the following categories: pulmonary, etiological, comorbidities, and lifestyle. Patients were further divided into four groups according to their post-MDD diagnosis: idiopathic ILD, sarcoidosis, connective tissue disease-ILD, and other ILD. The primary study outcome was the prevalence of each TT in the study population. A total of 116 patients with ILD [63.9% male; median (IQR) age: 69 (54-78) years] were included in the study. All the TTs identified in the literature were found in our cohort, except for intractable chronic cough. We also recognized differences in TTs across the ILD groups, with less TTs in patients with sarcoidosis. This analysis provides the first ancillary characterization of TTs in ILD patients in a real setting to date.

PMID:38791009 | DOI:10.3390/biomedicines12051047

Biomedicines. 2024 Apr 27;12(5):969. doi: 10.3390/biomedicines12050969.

ABSTRACT

Dysregulation of innate immunity is deeply involved in infectious and autoimmune diseases. For a better understanding of pathogenesis and improved management of these diseases, it is of vital importance to implement convenient monitoring of systemic innate immunity. Built upon our previous works on the host transcriptional response to infection in peripheral blood, we proposed a 2D gene model for the simultaneous assessment of two major components of systemic innate immunity, including VirSig as the signature of the host response to viral infection and BacSig as the signature of the host response to bacterial infection. The revelation of dysregulation in innate immunity by this 2D gene model was demonstrated with a wide variety of transcriptome datasets. In acute infection, distinctive patterns of VirSig and BacSig activation were observed in viral and bacterial infection. In comparison, both signatures were restricted to a defined range in the vast majority of healthy adults, regardless of age. In addition, BacSig showed significant elevation during pregnancy and an upward trend during development. In tuberculosis (TB), elevation of BacSig and VirSig was observed in a significant portion of active TB patients, and abnormal BacSig was also associated with a longer treatment course. In cystic fibrosis (CF), abnormal BacSig was observed in a subset of patients, and no overall change in BacSig abnormality was observed after the drug treatment. In systemic sclerosis-associated interstitial lung disease (SSc-ILD), significant elevation of VirSig and BacSig was observed in some patients, and treatment with a drug led to the further deviation of BacSig from the control level. In systemic lupus erythematosus (SLE), positivity for the anti-Ro autoantibody was associated with significant elevation of VirSig in SLE patients, and the additive effect of VirSig/BacSig activation was also observed in SLE patients during pregnancy. Overall, these data demonstrated that the 2D gene model can be used to assess systemic innate immunity in health and disease, with the potential clinical applications including patient stratification, prescription of antibiotics, understanding of pathogenesis, and longitudinal monitoring of treatment response.

PMID:38790931 | DOI:10.3390/biomedicines12050969

Children (Basel). 2024 Apr 24;11(5):507. doi: 10.3390/children11050507.

ABSTRACT

Psychosocial consequences of false-positive results following newborn bloodspot screening have been identified as a potential risk to this highly successful public health initiative. A scoping review was undertaken in October 2023 underpinned by the Arksey and O'Malley framework. Twenty-four papers were included in the review, many of which focused on cystic fibrosis. The results indicated that impact of false-positive results is variable; some studies suggest false-positive results have the potential to result in negative sequelae including increased stress and changes in parental perceptions of their child, while others suggest these impacts are transient and, in some instances, may even lead to positive outcomes. Further evidence is needed to ensure the representation of other conditions included in newborn bloodspot screening and to support strategies to overcome potential negative sequela.

PMID:38790502 | DOI:10.3390/children11050507

Children (Basel). 2024 Apr 23;11(5):505. doi: 10.3390/children11050505.

ABSTRACT

BACKGROUND: Infants presenting with unexpected pneumoperitoneum upon abdominal X-ray, indicating a gastrointestinal perforation (GIP), have a surgical emergency with potential morbidity and mortality. Preoperative determination of the location of perforation is challenging but will aid the surgeon in optimizing the surgical strategy, as colon perforations are more challenging than small bowel perforations. Therefore, the aim of this study is to provide an overview of preoperative patient characteristics, determine the differences between the small bowel and colon, and determine underlying causes in a cohort of infants with unexpected GIP.

METHODS: All infants (age ≤ 6 months) who presented at our center with unexpected pneumoperitoneum (no signs of pneumatosis before) undergoing surgery between 1996 and 2024 were retrospectively included. The differences between the location of perforation were analyzed using chi-squared and t-tests. Bonferroni correction was used to adjust for multiple tests.

RESULTS: In total, 51 infants presented with unexpected pneumoperitoneum at our center, predominantly male (N = 36/51) and premature (N = 40/51). Among them, twenty-six had small bowel, twenty-two colon, and three stomach perforations. Prematurity (p = 0.001), birthweight < 1000 g (p = 0.001), respiratory support (p = 0.001), and lower median arterial pH levels (p = 0.001) were more present in patients with small bowel perforation compared with colon perforations. Pneumatosis intestinalis was more present in patients with colon perforation (p = 0.004). All patients with Hirschsprung disease and cystic fibrosis had colon perforation. The final diagnoses were mainly focal intestinal perforations (N = 27/51) and necrotizing enterocolitis (N = 9/51).

CONCLUSIONS: Infants with unexpected GIP, birthweight < 1000 g, and prematurity have more risk for small bowel perforation. In case of colon perforation, additional screening (for Hirschsprung and cystic fibrosis) should be considered.

PMID:38790500 | DOI:10.3390/children11050505

Helicobacter. 2024 May-Jun;29(3):e13092. doi: 10.1111/hel.13092.

ABSTRACT

BACKGROUND: Helicobacter pylori may be found during upper gastrointestinal endoscopy (UGE) performed to diagnose celiac disease (CeD), inflammatory bowel disease (IBD), and eosinophilic esophagitis (EoE). We aimed to describe the frequency of H. pylori in children undergoing UGE for CeD, IBD, and EoE and the number of children receiving eradication treatment.

MATERIALS AND METHODS: A retrospective multicenter study from 14 countries included pediatric patients diagnosed with CeD, IBD, and EoE between January 2019 and December 2021.

DATA COLLECTED: age, gender, hematologic parameters, endoscopic, histologic, and H. pylori culture results, and information on eradication treatment.

RESULTS: H. pylori was identified in 349/3890 (9%) children [167 (48%) male, median 12 years (interquartile range 8.1-14.6)]. H. pylori was present in 10% (173/1733) CeD, 8.5% (110/1292) IBD and 7.6% (66/865) EoE patients (p = NS). The prevalence differed significantly between Europe (Eastern 5.2% (28/536), Southern 3.8% (78/2032), Western 5.6% (28/513)) and the Middle East 26.6% (215/809) [odds ratio (OR) 7.96 95% confidence interval (CI) (6.31-10.1) p < 0.0001]. Eradication treatment was prescribed in 131/349 (37.5%) patients, 34.6% CeD, 35.8% IBD, and 56.1% EoE. Predictors for recommending treatment included erosions/ulcers [OR 6.45 95% CI 3.62-11.47, p < 0.0001] and nodular gastritis [OR 2.25 95% CI 1.33-3.81, p 0.003]. Treatment rates were higher in centers with a low H. pylori prevalence (<20%) [OR 3.36 95% CI 1.47-7.66 p 0.004].

CONCLUSIONS: Identifying H. pylori incidentally during UGE performed for the most common gastrointestinal diseases varies significantly among regions but not among diseases. The indications for recommending treatment are not well defined, and less than 40% of children received treatment.

PMID:38790089 | DOI:10.1111/hel.13092

Sci Rep. 2024 May 24;14(1):11911. doi: 10.1038/s41598-024-62282-x.

ABSTRACT

Lack of understanding of the pathophysiology of gastrointestinal (GI) complications in type 1 diabetes (T1D), including altered intestinal transcriptomes and protein expression represents a major gap in the management of these patients. Human enteroids have emerged as a physiologically relevant model of the intestinal epithelium but establishing enteroids from individuals with long-standing T1D has proven difficult. We successfully established duodenal enteroids using endoscopic biopsies from pediatric T1D patients and compared them with aged-matched enteroids from healthy subjects (HS) using bulk RNA sequencing (RNA-seq), and functional analyses of ion transport processes. RNA-seq analysis showed significant differences in genes and pathways associated with cell differentiation and proliferation, cell fate commitment, and brush border membrane. Further validation of these results showed higher expression of enteroendocrine cells, and the proliferating cell marker Ki-67, significantly lower expression of NHE3, lower epithelial barrier integrity, and higher fluid secretion in response to cAMP and elevated calcium in T1D enteroids. Enteroids established from pediatric T1D duodenum identify characteristics of an abnormal intestinal epithelium and are distinct from HS. Our data supports the use of pediatric enteroids as an ex-vivo model to advance studies of GI complications and drug discovery in T1D patients.

PMID:38789719 | DOI:10.1038/s41598-024-62282-x

J Cyst Fibros. 2024 May 23:S1569-1993(24)00068-7. doi: 10.1016/j.jcf.2024.05.005. Online ahead of print.

ABSTRACT

BACKGROUND: Cystic fibrosis transmembrane conductance regulator (CFTR) modulators improve nutritional status and are of importance in achieving normal growth among younger children with CF. The study was designed to examine CFTR modulator-associated changes in nutrition status, including bile acids and fatty acids after lumacaftor/ivacaftor therapy for 24 weeks.

METHODS: Children 2 to 5.9 years were recruited from US and Canadian CF Centers. Eligible children were lumacaftor/ivacaftor naïve and approved to initiate therapy. Anthropometrics, diet, energy expenditure, nutrition biomarkers, pancreatic status, serum and fecal calprotectin, serum bile acids and plasma fatty acids were measured. Changes from baseline at 12 and 24 weeks were examined using mixed effects linear regression modeling.

RESULTS: Weight-for-age z-score (WAZ) increased at 12 (0.15 ± 0.1, p = 0.01) and 24 weeks (0.23 ± 0.1, p = 0.001) from baseline following modulator therapy. Head circumference-for-age (HCZ) increased at 12 weeks compared to baseline (0.22 ± 0.1, p = 0.03) and subscapular Z score increased from baseline at 24 weeks following therapy (0.33 ± 0.1, p = 0.02). There were no changes in energy expenditure. Serum total bile acids (6.7 ± 2.0, p = 0.001), chenodeoxycholic acid (CDCA) (2.4 ± 1.1, p = 0.001), and cholic acid (CA) (3.5 ± 0.8, p < 0.0001) increased at 24 weeks compared to baseline. Fecal calprotectin decreased at 12 and 24 weeks compared to baseline (-463 ± 310, p = 0.03 and 566 ± 347, p = 0.047). A number of plasma fatty acids changed over the course of 24 weeks of therapy. Noteably, alpha-linolenic acid (ALA) decreased at 12 and 24 weeks (-24 ± 10,p = 0.03 and -18 ± 10, p = 0.02, respectively).

CONCLUSIONS: Overall, young children experienced favorable changes in nutritional and growth, with the exception of plasma ALA status in the first 24 weeks of lumacaftor/ivacaftor therapy.

PMID:38789320 | DOI:10.1016/j.jcf.2024.05.005

J Cyst Fibros. 2024 May 23:S1569-1993(24)00067-5. doi: 10.1016/j.jcf.2024.05.004. Online ahead of print.

ABSTRACT

BACKGROUND: We recently demonstrated that 48 h exposure of primary human bronchial epithelial (hBE) cells, obtained from both CF (F508del homozygous) and non-CF subjects, to the triple drug combination Elexacaftor/Tezacaftor/Ivacaftor (ETI) results in a CFTR genotype-independent modulation of the de novo synthethic pathway of sphingolipids, with an accumulation of dihydroceramides (dHCer). Since dHCer are converted into ceramides (Cer) by the action of a delta-4 sphingolipid desaturase (DEGS) enzyme, we aimed to better understand this off-target effect of ETI (i.e., not related to CFTR rescue) METHODS: hBE cells, both F508del and wild-type, were cultured to create fully differentiated bronchial epithelia. We analyzed Cer and dHCer using an LC-MS based method previously developed by our lab. DEGS expression levels in differentiated hBE cells lysates were quantified by western blot analysis.

RESULTS: We demonstrated that 1) dHCer accumulate in hBE with time following prolonged ETI exposure, that 2) similar inhibition occurs in wild-type primary human hepatocytes and that 3) this does not result in an alteration of DEGS expression. We then proved that 4) ETI is a direct inhibitor of DEGS, that 5) Tezacaftor is the molecule responsible for this effect, that 6) the inhibition is concentration dependent. Finally, after repeated oral administration of ETI to naïve, non-CF, mice, we observed a slight accumulation of dHCer in the brain.

CONCLUSIONS: We believe that further investigations on Tezacaftor should be envisaged, particularly for the use of ETI during pregnancy, breastfeeding and in the early stages of development. DEGS dysfunction and dHCer accumulation causes impairment in the development of the nervous system, due to a derangement in myelin formation and maintenance.

PMID:38789319 | DOI:10.1016/j.jcf.2024.05.004

J Cyst Fibros. 2024 May 23:S1569-1993(24)00072-9. doi: 10.1016/j.jcf.2024.05.009. Online ahead of print.

ABSTRACT

BACKGROUND: Improved growth in children with CF may have resulted from advances in treatment for cystic fibrosis (CF) over the past two decades, including the implementation of newborn screening in Denmark in 2016. This observational cohort study focuses on changes in early growth in Danish children with CF born between 2000 and January 2022.

METHODS: Age, length/height, and weight data of children 0-5 years old were obtained from the Danish CF Cohort. Data were stratified to four birth cohorts born between 2000 and 2022. Weight-for-age (WAZ), length-for-age (LAZ), height-for-age (HAZ) and body-mass-index (BMZ) z-scores were computed using WHO growth curves. Cubic spline mixed effects models were used to evaluate growth over 5 years between birth cohorts.

RESULTS: We included 255 children in the analyses. Cubic spline mixed effects models show that catch-up growth improved in birth cohorts over time, with the 2016-2022 birth cohort achieving growth reference curve values in WAZ, LAZ/HAZ and BMZ the earliest. The proportion of underweight and stunting observations among children born 2000-2004 decreased by the 2016-2022 birth cohort, while the proportion of overweight, low BMZ and high BMZ observations increased.

CONCLUSION: Advances in care for young children with CF have led to improvements in growth - with the 2016-2022 birth cohort approaching potential for overweight. Nonetheless, low BMZ remains. Immediate, individualized nutrition care throughout early childhood remain crucial in mitigating malnutrition.

PMID:38789318 | DOI:10.1016/j.jcf.2024.05.009

J Cyst Fibros. 2024 May 23:S1569-1993(24)00070-5. doi: 10.1016/j.jcf.2024.05.007. Online ahead of print.

ABSTRACT

This is the final of four papers updating standards for the care of people with CF. That this paper "Planning a longer life" was considered necessary, highlights how much CF care has progressed over the past decade. Several factors underpin this progress, notably increased numbers of people with CF with access to CFTR modulator therapy. As the landscape for CF changes, so do the hopes and aspirations of people with CF and their families. This paper reflects the need to consider people with CF not as a "problem" to be solved, but as a success, a potential and a voice to be heard. People with CF and the wider CF community have driven this approach, reflecting many of the topics in this paper. This exercise involved wide stakeholder engagement. People with CF are keen to contribute to research priorities and be involved in all stages of research. People with CF want healthcare professionals to respect them as individuals and consider the impact of our actions on the world around us. Navigating life presents challenges to all, but for people with CF these challenges are heightened and complex. In this paper we highlight the concerns and life moments that impact people with CF, and events that the CF team should aim to support, including the challenges around having a family. People with CF and their care teams must embrace the updated standards outlined in these four papers to enjoy the full potential for a healthier life.

PMID:38789317 | DOI:10.1016/j.jcf.2024.05.007