Cell type-specific regulation of CFTR trafficking-on the verge of progress.

Trafficking of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein is a complex process that starts with its biosynthesis and folding in the endoplasmic reticulum. Exit from the endoplasmic reticulum (ER) is coupled with the acquisition of a compact structure that can be processed and traffic through the secretory pathway. Once reaching its final destination-the plasma membrane, CFTR stability is regulated through interaction with multiple protein partners that are involved in its post-translation modification, connecting the channel to several signaling pathways. The complexity of the process is further boosted when analyzed in the context of the airway epithelium. Recent advances have characterized in detail the different cell types that compose the surface epithelium and shifted the paradigm on which cells express CFTR and on their individual and combined contribution to the total expression (and function) of this chloride/bicarbonate channel. Here we review CFTR trafficking and its relationship with the knowledge on the different cell types of the airway epithelia. We explore the crosstalk between these two areas and discuss what is still to be clarified and how this can be used to develop more targeted therapies for CF.

Use of adenine base editing and homology-independent targeted integration strategies to correct the cystic fibrosis causing variant, W1282X.

Small molecule drugs known as modulators can treat ~90% of people with cystic fibrosis (CF), but do not work for premature termination codon variants such as W1282X (c.3846G>A). Here we evaluated two gene editing strategies, Adenine Base Editing (ABE) to correct W1282X, and Homology-Independent Targeted Integration (HITI) of a CFTR superexon comprising exons 23-27 (SE23-27) to enable expression of a CFTR mRNA without W1282X. In Flp-In-293 cells stably expressing a CFTR expression minigene bearing W1282X, ABE corrected 24% of W1282X alleles, rescued CFTR mRNA from nonsense mediated decay and restored protein expression. However, bystander editing at the adjacent adenine (c.3847A>G), caused an amino acid change (R1283G) that affects CFTR maturation and ablates ion channel activity. In primary human nasal epithelial cells homozygous for W1282X, ABE corrected 27% of alleles, but with a notably lower level of bystander editing, and CFTR channel function was restored to 16% of wild-type levels. Using the HITI approach, correct integration of a SE23-27 in intron 22 of the CFTR locus in 16HBEge W1282X cells was detected in 5.8% of alleles, resulting in 7.8% of CFTR transcripts containing the SE23-27 sequence. Analysis of a clonal line homozygous for the HITI-SE23-27 produced full-length mature protein and restored CFTR anion channel activity to 10% of wild-type levels, which could be increased three-fold upon treatment with the triple combination of CF modulators. Overall, these data demonstrate two different editing strategies can successfully correct W1282X, the second most common class I variant, with a concomitant restoration of CFTR function.

Personalized medicine: Function of CFTR variant p.Arg334Trp is rescued by currently available CFTR modulators.

Most of the 2,100 CFTR gene variants reported to date are still unknown in terms of their disease liability in Cystic Fibrosis (CF) and their molecular and cellular mechanism that leads to CFTR dysfunction. Since some rare variants may respond to currently approved modulators, characterizing their defect and response to these drugs is essential for effective treatment of people with CF (pwCF) not eligible for the current treatment. Here, we assessed how the rare variant, p.Arg334Trp, impacts on CFTR traffic and function and its response to existing CFTR modulators. To this end, we performed the forskolin-induced swelling (FIS) assay on intestinal organoids from 10 pwCF bearing the p.Arg334Trp variant in one or both alleles of the CFTR gene. In parallel, a novel p.Arg334Trp-CFTR expressing CFBE cell line was generated to characterize the variant individually. Results show that p.Arg334Trp-CFTR does not significantly affect the plasma membrane traffic of CFTR and evidences residual CFTR function. This CFTR variant is rescued by currently available CFTR modulators independently of the variant in the second allele. The study, predicting clinical benefit for CFTR modulators in pwCF with at least one p.Arg334Trp variant, demonstrates the high potential of personalized medicine through theranostics to extend the label of approved drugs for pwCF carrying rare CFTR variants. We recommend that this personalized approach should be considered for drug reimbursement policies by health insurance systems/national health services.

Rescue of Rare CFTR Trafficking Mutants Highlights a Structural Location-Dependent Pattern for Correction.

Cystic Fibrosis (CF) is a genetic disease caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) channel. Currently, more than 2100 variants have been identified in the gene, with a large number being very rare. The approval of modulators that act on mutant CFTR protein, correcting its molecular defect and thus alleviating the burden of the disease, revolutionized the field of CF. However, these drugs do not apply to all patients with CF, especially those with rare mutations-for which there is a lack of knowledge on the molecular mechanisms of the disease and the response to modulators. In this work, we evaluated the impact of several rare putative class II mutations on the expression, processing, and response of CFTR to modulators. Novel cell models consisting of bronchial epithelial cell lines expressing CFTR with 14 rare variants were created. The variants studied are localized at Transmembrane Domain 1 (TMD1) or very close to the signature motif of Nucleotide Binding Domain 1 (NBD1). Our data show that all mutations analyzed significantly decrease CFTR processing and while TMD1 mutations respond to modulators, those localized in NBD1 do not. Molecular modeling calculations confirm that the mutations in NBD1 induce greater destabilization of CFTR structure than those in TMD1. Furthermore, the structural proximity of TMD1 mutants to the reported binding site of CFTR modulators such as VX-809 and VX-661, make them more efficient in stabilizing the CFTR mutants analyzed. Overall, our data suggest a pattern for mutation location and impact in response to modulators that correlates with the global effect of the mutations on CFTR structure.

Mutation-class dependent signatures outweigh disease-associated processes in cystic fibrosis cells.

BACKGROUND: The phenotypic heterogeneity observed in Cystic Fibrosis (CF) patients suggests the involvement of other genes, besides CFTR. Here, we combined transcriptome and proteome analysis to understand the global gene expression patterns associated with five prototypical CFTR mutations. RESULTS: Evaluation of differentially expressed genes and proteins unveiled common and mutation-specific changes revealing functional signatures that are much more associated with the specific molecular defects associated with each mutation than to the CFTR loss-of-function phenotype. The combination of both datasets revealed that mutation-specific detected translated-transcripts (Dtt) have a high level of consistency. CONCLUSIONS: This is the first combined transcriptomic and proteomic study focusing on prototypical CFTR mutations. Analysis of Dtt provides novel insight into the pathophysiology of CF, and the mechanisms through which each mutation class causes disease and will likely contribute to the identification of new therapeutic targets and/or biomarkers for CF.

Fundamental and translational research in Cystic Fibrosis - why we still need it.

Clinical treatments for cystic fibrosis (CF) underwent significant changes in the last decade as therapies targeting the basic defect in the CFTR protein were approved. Significant scientific progress has also been made in several other areas that may lead in the future to novel therapeutic approaches that can help fight CF in all individuals living with this disease. Thus, focusing on fundamental research in the CF field has and will continue to be of great importance. This has been one of the aims of the European Cystic Fibrosis Society (ECFS), which has promoted the ECFS Basic Science Conference (BSC) every year since 2004. This special issue covers the topics featured and discussed at the 17th ECFS BSC, held in Albufeira (Portugal) in March 2022, and highlights advances in understanding CFTR, in using personalized medicine, and in developing innovative strategies to identify breakthrough therapies. This introduction highlights the topics presented throughout this special issue, thereby underscoring the relevance of fundamental research in CF.

The Effects of Combined Aquatic Exercise on Physical Performance and Metabolic Indices in Overweight Healthy Older Adults.

Addressing overweight and obesity to promote healthy aging is essential. Exercise is an outstanding approach to manage metabolic and physical dysfunction. Aquatic exercise has been recommended for older individuals due to reduced weight pressure on joints. The aim of this study was to determine the effects of twenty-eight weeks of combined aquatic exercise (aerobic and resistance) in overweight healthy older individuals. Thirty-two subjects of both genders with mean age of 72.06 ± 5.8 years were randomly assigned into two groups: an aquatic exercise group (EG; n = 19) and a control group (CG; n = 13). Body composition, anthropometric measurements, blood pressure, lipid profile, fasting glucose, insulin, and leptin were assessed before and after the training program. The lipid profile, fasting glucose, leptin, insulin, and insulin resistance did not change between and within groups. The lipid profile worsened in the CG. Reduction in body fat mass, waist and leg circumferences, along with body mass gain in the aquatic exercise group was observed (p ≤ 0.05). Systolic and diastolic blood pressure significantly improved in the exercise group (P = 0.003, P = 0.001). Significant differences were found in aerobic endurance (P = 0.008) and lower body flexibility (P = 0.049) of the aquatic exercise group compared with the control group. Also, upper body flexibility (P = 0.001, P = 0.020), lower and upper body strength (P = 0.001, P = 0.031), and handgrip (P = 0.001, P = 0.006), showed significant differences within the exercise group. Aquatic exercise may have a positive impact on the overweight aging population's metabolic and cardiovascular parameters, based on the observed improvements in blood pressure and body composition.

Effects of combined training during the COVID-19 pandemic on metabolic health and quality of life in sedentary workers: A randomized controlled study.

This study aimed to analyze the effects of a combined training (CT) program performed during the first national lockdown due to the COVID-19 pandemic on body composition, metabolic profile, quality of life and stress in sedentary workers, and examines whether changes in the metabolic profile are associated with changes in health-related outcomes which are modifiable by exercise. We evaluated 31 sedentary workers (48.26 ± 7.89 years old). Participants were randomly assigned to a CT group (i.e., performed 16 weeks of exercise) or to a non-exercise control group. The CT program consisted of 16-week of resistance and aerobic exercise. Body composition, glycemic and lipidic profiles, cardiorespiratory fitness (CRF), health-related quality of life and stress levels were assessed pre- and post-intervention. After the intervention period, the CT group demonstrated significantly lower waist and hip circumference (p < 0.05) values than the control group. The control group significantly increased the fasting glucose and HOMA-IR after 16 weeks follow-up (+4.74 mg/dL, p = 0.029; and +0.41 units, p = 0.010, respectively), whiles no significant changes were observed in the CT group in the same parameters (+3.33 mg/dL, p = 0.176; and +0.04 units, p = 0.628, respectively). No changes were observed in the lipid profile for either group (p > 0.05). A significant positive relationship was detected between the change in BMI with the changes in insulin and HOMA-IR (r = 0.643, p = 0.024; and r = 0.605, p = 0.037, respectively). In addition, the changes in CRF were negatively associated with the changes in total cholesterol (r = -0.578, p = 0.049). We observed differences between groups on perceived stress levels and physical, psychological, and environmental domains of quality of life, with the CT group showing better results. Moreover, the CT group improved perceived life satisfaction (+3.17 points, p = 0.038). The findings of the present study suggest that the participants who remained physically active during the first pandemic-related lockdown were able to mitigate the deleterious effects associated with a sedentary lifestyle.

The impact of aquatic exercise programs on the systemic hematological and inflammatory markers of community dwelling elderly: A randomized controlled trial.

Evidence shows that physical exercise is important in maintaining an efficient immune system during ageing. However, there are few studies that test the impact of aquatic exercise programs on the immune system. This study aims to analyze the impact of different physical exercise programs in aquatic environment on the systemic hematological and inflammatory markers of community dwelling elderly. One hundred and two elderly were randomly allocated into four groups: a continuous aerobic exercise group (AerG) (n = 25, 71.44 ± 4.84 years); an interval aerobic exercise group (IntG) (n = 28, 72.64 ± 5.22 years); a combined exercise group (ComG) (n = 29, 71.90 ± 5.67 years); a control group (CG) (n = 20, 73.60 ± 5.25 years). The AerG, IntG and ComG participants took part in three different aquatic exercise programs over a 28-weeks period. The CG participants maintained their usual routines during the same time period. Blood samples were collected from all participants in order to access hematologic indicators, by means of cell count, and the inflammatory profile by ELISA. After 28 weeks, significant differences were found for several hematologic variables in the AerG, IntG and ComG with increases in mean corpuscular hemoglobulin (MCH), mean corpuscular hemoglobulin concentration (MCHC), and hemoglobulin (Hb). Decreases in TNF-α levels were found for all exercising groups. An increase in IL-10 levels, granulocytes to lymphocytes ratio (GLR) and a decrease in the TNF-α/IL-10 ratio, were found for the IntG. For the ComG decreases were also found for the TNF-α, IL-1ß/IL-1ra ratios. The present study suggests that aquatic exercise programs were able to improve the inflammatory profile of the participants. Those in the exercise intervention groups showed a shift towards lower pro-inflammatory levels while the non-exercising group showed the opposite behaviour. The IntG and the ComG aquatic exercise programs appeared to be more effective than the AerG program in decreasing chronic low-grade inflammation by mediating the production of higher levels of anti-inflammatory cytokines. However, the differences found between the exercising groups were small and may not have clinical significance.

Absence of EPAC1 Signaling to Stabilize CFTR in Intestinal Organoids.

The plasma membrane (PM) stability of the cystic fibrosis transmembrane conductance regulator (CFTR), the protein which when mutated causes Cystic Fibrosis (CF), relies on multiple interaction partners that connect CFTR to signaling pathways, including cAMP signaling. It was previously shown that activation of exchange protein directly activated by cAMP 1 (EPAC1) by cAMP promotes an increase in CFTR PM levels in airway epithelial cells. However, the relevance of this pathway in other tissues, particularly the intestinal tissue, remains uncharacterized. Here, we used Western blot and forskolin-induced swelling assay to demonstrate that the EPAC1 protein is not expressed in the intestinal organoid model, and consequently the EPAC1 stabilization pathway is not in place. On the other hand, using cell surface biotinylation, EPAC1-mediated stabilization of PM CFTR is observed in intestinal cell lines. These results indicate that the EPAC1 stabilization pathway also occurs in intestinal cells and is a potential target for the development of novel combinatorial therapies for treatment of CF.

Severity of the S1251N allele in cystic fibrosis is affected by the presence of the F508C variant in cis.

BACKGROUND: In cystic fibrosis (CF), genotype-phenotype correlation is complicated by the large number of CFTR variants, the influence of modifier genes, environmental effects, and the existence of complex alleles. We document the importance of complex alleles, in particular the F508C variant present in cis with the S1251N disease-causing variant, by detailed analysis of a patient with CF, with the [S1251N;F508]/G542X genotype and a very mild phenotype, contrasting it to that of four subjects with the [S1251N;F508C]/F508del genotype and classical CF presentation. METHODS: Genetic differences were identified by Sanger sequencing and CFTR function was quantified using rectal organoids in rectal organoid morphology analysis (ROMA) and forskolin-induced swelling (FIS) assays. CFTR variants were further characterised in CF bronchial epithelial (CFBE) cell lines. The impact of involved amino acid changes in the CFTR 3D protein structure was evaluated. RESULTS: Organoids of the patient [S1251N;F508] with mild CF phenotype confirmed the CF diagnosis but showed higher residual CFTR function compared to the four others [S1251N;F508C]. CFBE cell lines showed a decrease in [S1251N;F508C]-CFTR function but not in processing when compared to [S1251N;F508]-CFTR. Analysis of the 3D CFTR structure suggested an additive deleterious effect of the combined presence of S1251N and F508C with respect to NBD1-2 dimerisation. CONCLUSIONS: In vitro and in silico data show that the presence of F508C in cis with S1251N decreases CFTR function without affecting processing. Complex CFTR alleles play a role in clinical phenotype and their identification is relevant in the context of personalised medicine for each patient with CF.

Molecular mechanisms of cystic fibrosis - how mutations lead to misfunction and guide therapy.

Cystic fibrosis, the most common autosomal recessive disorder in Caucasians, is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which encodes a cAMP-activated chloride and bicarbonate channel that regulates ion and water transport in secretory epithelia. Although all mutations lead to the lack or reduction in channel function, the mechanisms through which this occurs are diverse - ranging from lack of full-length mRNA, reduced mRNA levels, impaired folding and trafficking, targeting to degradation, decreased gating or conductance, and reduced protein levels to decreased half-life at the plasma membrane. Here, we review the different molecular mechanisms that cause cystic fibrosis and detail how these differences identify theratypes that can inform the use of directed therapies aiming at correcting the basic defect. In summary, we travel through CFTR life cycle from the gene to function, identifying what can go wrong and what can be targeted in terms of the different types of therapeutic approaches.

The Impact of Aquatic Exercise Programs on the Intima-Media thickness of the Carotid Arteries, Hemodynamic Parameters, Lipid Profile and Chemokines of Community-Dwelling Older Persons: A Randomized Controlled Trial.

Scientific evidence has shown that physical exercise is an effective way of improving several cardiovascular disease markers. However, few studies have tested its effectiveness when performed in aquatic environments. The purpose of this study was to test the impact of different aquatic exercise programs on the intima-media thickness of carotid arteries (IMT) and hemodynamic and biochemical markers of cardiovascular diseases in community-dwelling older persons. A total of 102 participants were randomly allocated into four groups: an aerobic exercise group (AerG) (n = 25, 71.44 ± 4.84 years); an aerobic interval group (IntG) (n = 28, 72.64 ± 5.22 years); a combined group (ComG) (n = 29, 71.90 ± 5.67 years); and a control group (CG) (n = 20, 73.60 ± 5.25 years). The AerG, IntG, and ComG participants took part in three different aquatic exercise programs for 28 weeks. The CG participants maintained their usual routines. All participants were evaluated for IMT, blood pressure, lipid profile, and MCP-1 and MIP-1α chemokines, pre- and post-intervention. Significant differences were found in the AerG for diastolic diameter (DD), in the IntG for peak systolic velocity (PSV), and in the ComG for DD and end-diastolic velocity (EDV). Regarding blood pressure, significant differences were found in AerG for systolic blood pressure (SBP) and diastolic blood pressure (DBP); in IntG for DBP; and in ComG for SBP, DBP, and heart rate (HR). Significant differences were found in the AerG and IntG for glucose (GLU). Lower plasma levels of monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein (MIP-1α) were found in the AerG and in the ComG for MCP-1 after the intervention. Aquatic physical exercise appears to improve cardiovascular health, regardless of the type of the program adopted. Aerobic programs (combined and continuous aerobic exercises) seemed to have a more beneficial effect in reducing important cardiovascular risk markers.

Rescue of Mutant CFTR Trafficking Defect by the Investigational Compound MCG1516A.

Although some therapeutic progress has been achieved in developing small molecules that correct F508del-CFTR defects, the mechanism of action (MoA) of these compounds remain poorly elucidated. Here, we investigated the effects and MoA of MCG1516A, a newly developed F508del-CFTR corrector. MCG1516A effects on wild-type (WT) and F508del-CFTR were assessed by immunofluorescence microscopy, and biochemical and functional assays both in cell lines and in intestinal organoids. To shed light on the MoA of MCG1516A, we evaluated its additivity to the FDA-approved corrector VX-661, low temperature, genetic revertants of F508del-CFTR (G550E, R1070W, and 4RK), and the traffic-null variant DD/AA. Finally, we explored the ability of MCG1516A to rescue trafficking and function of other CF-causing mutations. We found that MCG1516A rescues F508del-CFTR with additive effects to VX-661. A similar behavior was observed for WT-CFTR. Under low temperature incubation, F508del-CFTR demonstrated an additivity in processing and function with VX-661, but not with MCG1516A. In contrast, both compounds promoted additional effects to low temperature to WT-CFTR. MCG1516A demonstrated additivity to genetic revertant R1070W, while VX-661 was additive to G550E and 4RK. Nevertheless, none of these compounds rescued DD/AA trafficking. Both MCG1516A and VX-661 rescued CFTR processing of L206W- and R334W-CFTR with greater effects when these compounds were combined. In summary, the absence of additivity of MCG1516A to genetic revertant G550E suggests a putative binding site for this compound on NBD1:NBD2 interface. Therefore, a combination of MCG1516A with compounds able to rescue DD/AA traffic, or mimicking the actions of revertant R1070W (e.g., VX-661), could enhance correction of F508del-CFTR defects.

Comparison of Cas9 and Cas12a CRISPR editing methods to correct the W1282X-CFTR mutation.

BACKGROUND: W1282X-CFTR variant (c.3846G>A) is the second most common nonsense cystic fibrosis (CF)-causing mutation in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. Even though remarkable breakthroughs have been done towards CF treatment with the approval of four CFTR protein modulators, none of these are approved for patients with nonsense mutations. CRISPR gene editing tools can be of great value to permanently correct the genetic defects caused by these mutations. METHODS: We compared the capacity of homology-directed repair (HDR) mediated by Cas9 or Cas12a to correct W1282X CFTR mutation in the CFF-16HBEge W1282X CFTR cell line (obtained from CFF), using Cas9/gRNA and Cas12a/gRNA ribonucleoproteins (RNPs) and single strand DNA (ssODN) oligonucleotide donors. RESULTS: Cas9 shows higher levels of correction than Cas12a as, by electroporating cells with Cas9 RNPs and ssODN donor, nearly 18% of precise editing was achieved compared to just 8% for Cas12a. Such levels of correction increase the abundance of CFTR mRNA and protein, and partially restore CFTR function in the pool of edited cells to 18% of WT CFTR function. Moreover, homozygous corrected clones produced levels of mRNA, protein, and function comparable to those of cells expressing WT CFTR. CONCLUSION: Altogether, this work demonstrates the potential of gene editing as a therapeutic strategy for CF directly correcting the root cause of the disease.

Revisiting CFTR Interactions: Old Partners and New Players.

Remarkable progress in CFTR research has led to the therapeutic development of modulators that rescue the basic defect in cystic fibrosis. There is continuous interest in studying CFTR molecular disease mechanisms as not all cystic fibrosis patients have a therapeutic option available. Addressing the basis of the problem by comprehensively understanding the critical molecular associations of CFTR interactions remains key. With the availability of CFTR modulators, there is interest in comprehending which interactions are critical to rescue CFTR and which are altered by modulators or CFTR mutations. Here, the current knowledge on interactions that govern CFTR folding, processing, and stability is summarized. Furthermore, we describe protein complexes and signal pathways that modulate the CFTR function. Primary epithelial cells display a spatial control of the CFTR interactions and have become a common system for preclinical and personalized medicine studies. Strikingly, the novel roles of CFTR in development and differentiation have been recently uncovered and it has been revealed that specific CFTR gene interactions also play an important role in transcriptional regulation. For a comprehensive understanding of the molecular environment of CFTR, it is important to consider CFTR mutation-dependent interactions as well as factors affecting the CFTR interactome on the cell type, tissue-specific, and transcriptional levels.

CyFi-MAP: an interactive pathway-based resource for cystic fibrosis.

Cystic fibrosis (CF) is a life-threatening autosomal recessive disease caused by more than 2100 mutations in the CF transmembrane conductance regulator (CFTR) gene, generating variability in disease severity among individuals with CF sharing the same CFTR genotype. Systems biology can assist in the collection and visualization of CF data to extract additional biological significance and find novel therapeutic targets. Here, we present the CyFi-MAP-a disease map repository of CFTR molecular mechanisms and pathways involved in CF. Specifically, we represented the wild-type (wt-CFTR) and the F508del associated processes (F508del-CFTR) in separate submaps, with pathways related to protein biosynthesis, endoplasmic reticulum retention, export, activation/inactivation of channel function, and recycling/degradation after endocytosis. CyFi-MAP is an open-access resource with specific, curated and continuously updated information on CFTR-related pathways available online at https://cysticfibrosismap.github.io/ . This tool was developed as a reference CF pathway data repository to be continuously updated and used worldwide in CF research.

Integrity and Stability of PTC Bearing CFTR mRNA and Relevance to Future Modulator Therapies in Cystic Fibrosis.

Major advances have recently been made in the development and application of CFTR (cystic fibrosis transmembrane conductance regulator) mutation class-specific modulator therapies, but to date, there are no approved modulators for Class I mutations, i.e., those introducing a premature termination codon (PTC) into the CFTR mRNA. Such mutations induce nonsense-mediated decay (NMD), a cellular quality control mechanism that reduces the quantity of PTC bearing mRNAs, presumably to avoid translation of potentially deleterious truncated CFTR proteins. The NMD-mediated reduction of PTC-CFTR mRNA molecules reduces the efficacy of one of the most promising approaches to treatment of such mutations, namely, PTC readthrough therapy, using molecules that induce the incorporation of near-cognate amino acids at the PTC codon, thereby enabling translation of a full-length protein. In this study, we measure the effect of three different PTC mutations on the abundance, integrity, and stability of respective CFTR mRNAs, using CFTR specific RT-qPCR-based assays. Altogether, our data suggest that optimized rescue of PTC mutations has to take into account (1) the different steady-state levels of the CFTR mRNA associated with each specific PTC mutation; (2) differences in abundance between the 3' and 5' regions of CFTR mRNA, even following PTC readthrough or NMD inhibition; and (3) variable effects on CFTR mRNA stability for each specific PTC mutation.

Impact of Different Aquatic Exercise Programs on Body Composition, Functional Fitness and Cognitive Function of Non-Institutionalized Elderly Adults: A Randomized Controlled Trial.

Aquatic physical exercise programs have become progressively more popular among elderly people. Some of the major physical exercise program disadvantages on land are minimized due to the specific properties of the aquatic environment. The purpose of the present randomized controlled study is to verify the effects of different aquatic physical exercise programs on body composition, functional fitness and cognitive function in non-institutionalized elderly people. For this study, 102 elderly individuals were randomly allocated into four different groups: AerG (n = 25, 71.44 ± 4.84 years); IntG (n = 28, 72.64 ± 5.22 years); ComG (n = 29, 71.90 ± 5.67 years) and CG (n = 20, 73.60 ± 5.25 years). Individuals from the groups AerG, IntG and ComG participated in three different aquatic physical exercise programs for a period of 28 weeks. The CG participants kept to their usual routines. All participants were evaluated for body composition, functional fitness and cognitive function at two time moments, i.e., pre- (M1) and post-intervention (M2). Significant differences for body composition were found between M1 and M2 for FM (p < 0.001), LBM (p < 0.001) and WCir (p < 0.01) in the AerG, for BMI (p < 0.05), FM (p < 0.05), LBM (p < 0.001) and LCir-R (p < 0.05) in the IntG, and for WGT (p < 0.01), FM (p < 0.05), LBM (p < 0.01), LCir-R (p < 0.05) and LCir-L (p < 0.01) in the ComG groups. For functional fitness, differences were found between M1 and M2 for 2m-ST (p < 0.000), 30s-CS (p < 0.000), 30s-AC (p < 0.05), HG-T-R (p < 0.000) and HG-T-L (p < 0.000) in the AerG, for 2m-ST (p < 0.05), BS-R (p < 0.05), 30s-CS (p < 0.000), 30s-AC(p < 0.01), HG-T-R (p < 0.000) and HG-T-L (p < 0.000) in the IntG, and for 30s-CS (p < 0.000), HG-T-R (p < 0.000) and HG-T-L (p < 0.000) in the ComG groups. The present study evidenced the beneficial effects of physical exercise in an aquatic environment on body composition, functional fitness and cognitive function in non-institutionalized elderly adults. The ComG water-based exercise program showed more beneficial effects in the improvement of body composition and cognitive function variables, while the IntG and AerG programs were more effective in the improvement of functional fitness.