scholarly journals Esc peptides as novel potentiators of defective cystic fibrosis transmembrane conductance regulator: an unprecedented property of antimicrobial peptides

2021 ◽  
Author(s):  
Loretta Ferrera ◽  
Floriana Cappiello ◽  
Maria Rosa Loffredo ◽  
Elena Puglisi ◽  
Bruno Casciaro ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Antimicrobial Peptides ◽  
Lung Disease ◽  
Bacterial Infections ◽  
Wound Repair ◽  
Direct Interaction ◽  
Transmembrane Conductance Regulator ◽  
Transmembrane Conductance ◽  
Advanced Stages ◽  
Cf Transmembrane Conductance Regulator

AbstractMutations in the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein lead to persistent lung bacterial infections, mainly due to Pseudomonas aeruginosa, causing loss of respiratory function and finally death of people affected by CF. Unfortunately, even in the era of CFTR modulation therapies, management of pulmonary infections in CF remains highly challenging especially for patients with advanced stages of lung disease. Recently, we identified antimicrobial peptides (AMPs), namely Esc peptides, with potent antipseudomonal activity. In this study, by means of electrophysiological techniques and computational studies we discovered their ability to increase the CFTR-controlled ion currents, by direct interaction with the F508del-CFTR mutant. Remarkably, this property was not explored previously with any AMPs or peptides in general. More interestingly, in contrast with clinically used CFTR modulators, Esc peptides would give particular benefit to CF patients by combining their capability to eradicate lung infections and to act as promoters of airway wound repair with their ability to ameliorate the activity of the channel with conductance defects. Overall, our findings not only highlighted Esc peptides as the first characterized AMPs with a novel property, that is the potentiator activity of CFTR, but also paved the avenue to investigate the functions of AMPs and/or other peptide molecules, for a new up-and-coming pharmacological approach to address CF lung disease.

scholarly journals The CFTR and ENaC debate: how important is ENaC in CF lung disease?

2012 ◽  
Vol 302 (11) ◽  
pp. L1141-L1146 ◽  
Author(s):  
James F. Collawn ◽  
Ahmed Lazrak ◽  
Zsuzsa Bebok ◽  
Sadis Matalon
Keyword(s):  
Cystic Fibrosis ◽  
Lung Disease ◽  
Bacterial Infections ◽  
Transmembrane Conductance Regulator ◽  
Transmembrane Conductance ◽  
Ongoing Debate ◽  
The Subject ◽  
Cystic Fibrosis Transmembrane ◽  
Epithelial Sodium Channel Enac

Cystic fibrosis (CF) is caused by the loss of the cystic fibrosis transmembrane conductance regulator (CFTR) function and results in a respiratory phenotype that is characterized by dehydrated mucus and bacterial infections that affect CF patients throughout their lives. Much of the morbidity and mortality in CF results from a failure to clear bacteria from the lungs. What causes the defect in the bacterial clearance in the CF lung has been the subject of an ongoing debate. Here we discuss the arguments for and against the role of the epithelial sodium channel, ENaC, in the development of CF lung disease.

scholarly journals Postnatal airway growth in cystic fibrosis piglets

2017 ◽  
Vol 123 (3) ◽  
pp. 526-533 ◽  
Author(s):  
Ryan J. Adam ◽  
Mahmoud H. Abou Alaiwa ◽  
Drake C. Bouzek ◽  
Daniel P. Cook ◽  
Nicholas D. Gansemer ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Lung Disease ◽  
Lung Volume ◽  
Growth And Development ◽  
Anion Channel ◽  
Postnatal Period ◽  
Transmembrane Conductance Regulator ◽  
Transmembrane Conductance ◽  
Disease Pathogenesis ◽  
Cf Transmembrane Conductance Regulator

Mutations in the gene encoding the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) anion channel cause CF. The leading cause of death in the CF population is lung disease. Increasing evidence suggests that in utero airway development is CFTR-dependent and that developmental abnormalities may contribute to CF lung disease. However, relatively little is known about postnatal CF airway growth, largely because such studies are limited in humans. Therefore, we examined airway growth and lung volume in a porcine model of CF. We hypothesized that CF pigs would have abnormal postnatal airway growth. To test this hypothesis, we performed CT-based airway and lung volume measurements in 3-wk-old non-CF and CF pigs. We found that 3-wk-old CF pigs had tracheas of reduced caliber and irregular shape. Their bronchial lumens were reduced in size proximally but not distally, were irregularly shaped, and had reduced distensibility. Our data suggest that lack of CFTR results in aberrant postnatal airway growth and development, which could contribute to CF lung disease pathogenesis. NEW & NOTEWORTHY This CT scan-based study of airway morphometry in the cystic fibrosis (CF) postnatal period is unique, as analogous studies in humans are greatly limited for ethical and technical reasons. Findings such as reduced airway lumen area and irregular caliber suggest that airway growth and development are CF transmembrane conductance regulator-dependent and that airway growth defects may contribute to CF lung disease pathogenesis.

scholarly journals VX-809 corrects folding defects in cystic fibrosis transmembrane conductance regulator protein through action on membrane-spanning domain 1

2013 ◽  
Vol 24 (19) ◽  
pp. 3016-3024 ◽  
Author(s):  
Hong Yu Ren ◽  
Diane E. Grove ◽  
Oxana De La Rosa ◽  
Scott A. Houck ◽  
Pattarawut Sopha ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Chloride Transport ◽  
Genetic Disorder ◽  
Missense Mutations ◽  
Transmembrane Conductance Regulator ◽  
Transmembrane Conductance ◽  
Regulator Protein ◽  
Folding Defect ◽  
Membrane Spanning ◽  
Cf Transmembrane Conductance Regulator

Cystic fibrosis (CF) is a fatal genetic disorder associated with defective hydration of lung airways due to the loss of chloride transport through the CF transmembrane conductance regulator protein (CFTR). CFTR contains two membrane-spanning domains (MSDs), two nucleotide-binding domains (NBDs), and a regulatory domain, and its channel assembly requires multiple interdomain contacts. The most common CF-causing mutation, F508del, occurs in NBD1 and results in misfolding and premature degradation of F508del-CFTR. VX-809 is an investigational CFTR corrector that partially restores CFTR function in people who are homozygous for F508del-CFTR. To identify the folding defect(s) in F508del-CFTR that must be repaired to treat CF, we explored the mechanism of VX-809 action. VX-809 stabilized an N-terminal domain in CFTR that contains only MSD1 and efficaciously restored function to CFTR forms that have missense mutations in MSD1. The action of VX-809 on MSD1 appears to suppress folding defects in F508del-CFTR by enhancing interactions among the NBD1, MSD1, and MSD2 domains. The ability of VX-809 to correct F508del-CFTR is enhanced when combined with mutations that improve F508del-NBD1 interaction with MSD2. These data suggest that the use of VX-809 in combination with an additional CFTR corrector that suppresses folding defects downstream of MSD1 may further enhance CFTR function in people with F508del-CFTR.

scholarly journals Maturation and function of cystic fibrosis transmembrane conductance regulator variants bearing mutations in putative nucleotide-binding domains 1 and 2.

1991 ◽  
Vol 11 (8) ◽  
pp. 3886-3893 ◽  
Author(s):  
R J Gregory ◽  
D P Rich ◽  
S H Cheng ◽  
D W Souza ◽  
S Paul ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Amino Acid ◽  
Functional Activity ◽  
Nucleotide Binding ◽  
Missense Mutations ◽  
Transmembrane Conductance Regulator ◽  
Transmembrane Conductance ◽  
Fluorescence Measurements ◽  
Cf Transmembrane Conductance Regulator ◽  
Altered Proteins

One feature of the mutations thus far found to be associated with the disease cystic fibrosis (CF) is that many of them are clustered within the first nucleotide-binding domain (NBD) of the CF transmembrane conductance regulator (CFTR). We sought to discover the molecular basis for this clustering by introducing into the two NBDs of CFTR mutations either mimicking amino acid changes associated with CF or altering residues within highly conserved motifs. Synthesis and maturation of the mutant CFTR were studied by transient expression in COS cells. The ability of the altered proteins to generate cyclic AMP-stimulated anion efflux was assessed by using 6-methoxy-N-(sulfopropyl) quinolinium (SPQ) fluorescence measurements in HeLa cells expressing mutated plasmids. The results show that (i) all CF-associated mutants, with one exception, lack functional activity as measured in the SPQ assay, (ii) mutations in NBD1 are more sensitive to the effects of the same amino acid change than are the corresponding mutations in NBD2, (iii) cells transfected with plasmids bearing CF-associated mutations commonly but not exclusively lack mature CFTR, (iv) NBD mutants lacking mature CFTR fail to activate Cl- channels, and (v) the glycosylation of CFTR, per se, is not required for CFTR function. We reason that the structure of NBD1 itself or of the surrounding domains renders it particularly sensitive to mutational changes. As a result, most NBD1 mutants, but only a few NBD2 mutants, fail to mature or lack functional activity. These findings are consistent with the observed uneven distribution of CFTR missense mutations between NBD1 and NBD2 of CF patients.

scholarly journals Dysfunctional cystic fibrosis transmembrane conductance regulator inhibits phagocytosis of apoptotic cells with proinflammatory consequences

2009 ◽  
Vol 297 (4) ◽  
pp. L677-L686 ◽  
Author(s):  
R. William Vandivier ◽  
Tiffany R. Richens ◽  
Sarah A. Horstmann ◽  
Aimee M. deCathelineau ◽  
Moumita Ghosh ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Rho Kinase ◽  
Negative Regulator ◽  
Apoptotic Cells ◽  
Transmembrane Conductance Regulator ◽  
Transmembrane Conductance ◽  
Altered Expression ◽  
Proinflammatory Mediators ◽  
Downstream Effector ◽  
Cf Transmembrane Conductance Regulator

Cystic fibrosis (CF) is caused by mutated CF transmembrane conductance regulator (CFTR) and is characterized by robust airway inflammation and accumulation of apoptotic cells. Phagocytosis of apoptotic cells (efferocytosis) is a pivotal regulator of inflammation, because it prevents postapoptotic necrosis and actively suppresses release of a variety of proinflammatory mediators, including IL-8. Because CF is associated with accumulation of apoptotic cells, inappropriate levels of IL-8, and robust inflammation, we sought to determine whether CFTR deficiency specifically impairs efferocytosis and its regulation of inflammatory mediator release. Here we show that CFTR deficiency directly interferes with efferocytosis by airway epithelium, an effect that is not due to altered binding of apoptotic cells to epithelial cells or altered expression of efferocytosis receptors. In contrast, expression of RhoA, a known negative regulator of efferocytosis, is substantially increased in CFTR-deficient cells, and inhibitors of RhoA or its downstream effector Rho kinase normalize efferocytosis in these cells. Impaired efferocytosis appears to be mediated through an amiloride-sensitive ion channel, because amiloride restores phagocytic competency in CFTR-deficient cells. Finally, ineffective efferocytosis in CFTR-deficient cells appears to have proinflammatory consequences, because apoptotic cells enhance IL-8 release by these cells, but not by wild-type controls. Therefore, in CF, dysregulated efferocytosis may lead to accumulation of apoptotic cells and impaired regulation of the inflammatory response and, ultimately, may suggest a new therapeutic target.

Sign in / Sign up

Export Citation Format

Share Document