From the Ketogenic Diet to the Mediterranean Diet: The Potential Dietary Therapy in Patients with Obesity after CoVID-19 Infection (Post CoVID Syndrome)

PURPOSE OF REVIEW

This review primarily examines the evidence for areas of consensus and on-going uncertainty or controversy about diet and physical exercise approaches for in the post-CoVID. We propose an ideal dietary and physical activity approach that the patient with obesity should follow after CoVID-19 infection in order to reduce the clinical conditions associated with post-CoVID syndrome.

RECENT FINDINGS

The CoVID-19 disease pandemic, caused by the severe acute respiratory syndrome coronavirus-2, has spread all over the globe, infecting hundreds of millions of individuals and causing millions of death. It is also known to be is associated with several medical and psychological complications, especially in patients with obesity and weight-related disorders who in general pose a significant global public health problem, and in specific affected individuals are on a greater risk of developing poorer CoVID-19 clinical outcomes and experience a higher rate of mortality. Little is still known about the best nutritional approach to be adopted in this disease especially in the patients post-CoVID syndrome. To the best of our knowledge, no specific nutritional recommendations exist to manage in the patients post-CoVID syndrome. We report a presentation of nutritional therapeutic approach based on a ketogenic diet protocol followed by a transition to the Mediterranean diet in patients post-infection by CoVID, combined to a physical activity program to address conditions associated with post-CoVID syndrome.

Clinical and nutritional management of very-low-calorie ketogenic diet (VLCKD) in patients with psoriasis and obesity: a practical guide for the nutritionist

Psoriasis is an immune-mediated inflammatory skin disease associated with multiple comorbidities. Considered one of the most common inflammatory skin diseases among the general population, it not only affects the skin, but also negatively impacts other organs and joints. In addition, psoriasis has been associated with several chronic cardio-metabolic diseases such as obesity, which would seem to be (i) a risk factor for the onset of psoriasis and (ii) a worsening factor of the severity of the disease. Weight loss appears to improve severity in overweight patients. Recently proposed as an obesity management nutritional strategy, the very-low-calorie ketogenic diet (VLCKD) has demonstrated significant effects in reducing inflammatory processes. In the current review, we describe the evidence available on psoriasis and VLCKD, and provide a practical guide to the prescription of VLCKD in the different phases, evaluation and management of possible adverse events, and the importance of physical activity as a lifestyle modification to reduce psoriasis and associated comorbidities. Randomized control trials are, however, necessary to determine the most effective VLCKD protocol for patients with obesity and psoriasis, optimal protocol duration, composition of micronutrients and macronutrients, choice of special supplements, and management of carbohydrate reintroduction.

Treatment with sera from Water Polo athletes activates AMPKα and ACC proteins In HepG2 hepatoma cell line

Purpose

Physical activity and professional physical activity such as water polo (WP) sport, has numerous beneficial effects to fight metabolism-related disorders through several mechanisms, including the promotion of liver metabolic adaptations, and the modulation of cytokine production. The aim of this study was to investigate the effects of different types of physical activity on AMPKα and ACC, two proteins involved in liver metabolism; therefore, we treated the hepatoma cell line Hep G2 with sera from elite WP athletes and amateur (basket) players. As control, we used serum from both sedentary and obese subjects.

Methods

Help G2 cells were treated with 5% of human sera from the different subjects; after 24 h and 48 h, HepG2 cell viability was verified through MTT assay and activation status of AMPKα and ACC through western blotting. Cytokine’s serum levels were measured through ELISA assay.

Results

After 72 h, the treatment of HepG2 cells with sera from the different subjects produced no effect on cell viability. Furthermore, after 48 h of treatment, both AMPKα and ACC phosphorylation statistically increases in HepG2 cells treated with sera from WP athletes. Furthermore, IL-4, IL-6 and IL-10 levels resulted statistically increased in WP athlete’s sera than in sedentary subjects.

Conclusion

The specific activation of AMPKα and ACC by WP sera confirms that professional sport activity carried out by WP athletes can be considered as a physiological activator of these two proteins also in HepG2 liver cells. In addition, the increase of anti-inflammatory cytokines in WP sera confirms the ample evidence for multiple anti-inflammatory activities carried out by WP discipline.

Physical Activity Regulates TNFα and IL-6 Expression to Counteract Inflammation in Cystic Fibrosis Patients

Background: Cystic fibrosis (CF) is one of the most common inherited diseases. It is characterised by a severe decline in pulmonary function associated with metabolic perturbations and an increased production of inflammatory cytokines. The key role of physical activity (PA) in improving the health status of CF patients and reducing lung function decline has recently been demonstrated. This study evaluated interleukin-6 (IL-6) and tumour necrosis factor α (TNFα) expression in two subgroups of CF patients classified based on PA. Methods: We selected 85 CF patients; half of them regularly undertook supervised PA in the three years leading up to the study and half of them were not physically active. Patients were analysed for serum IL-6 and TNFα levels using enzyme-linked immunosorbent assays. Results: We found that the expression levels of IL-6 and TNFα differed in terms of their regulation by PA. In particular, TNFα levels negatively correlated with FEV1% decrease/year and FEV1% decrease (p = 0.023 and p = 0.02, respectively), and positively correlated with serum fasting glucose (p = 0.019) in PA CF patients. In contrast, in the NPA subgroup, TNFα levels were positively correlated with IL-6 (p = 0.001) and negatively correlated with adiponectin (p = 0.000). In addition, multiple logistic regression analysis confirmed that PA is an independent modulator of the inflammatory state. Conclusions: PA modulates inflammatory processes in CF patients by regulating the secretion of pro-inflammatory cytokines and thus ameliorating lung function. Our data show that PA is a useful complementary strategy in the management of CF and that TNFα may be a marker of these effects of PA.

Molecular mechanisms involved in the positive effects of physical activity on coping with COVID-19

PURPOSE

Physical activity (PA) represents the first line of defence against diseases characterised by increased inflammation status, such as metabolic and infectious diseases. Conversely, a sedentary lifestyle-associated with obesity, type 2 diabetes and cardiovascular disorders-negatively impacts on general health status, including susceptibility to infections. At a time of a pandemic SARS-CoV2 infection, and in the context of the multiorgan crosstalk (widely accepted as a mechanism participating in the pathophysiology of all organs and systems), we examine the complex interplay mediated by skeletal muscle contraction involving the immune system and how this contributes to control health status and to counteract viral infections. In so doing, we review the molecular mechanisms and expression of molecules modulated by PA, able to provide the proper molecular equipment against viral infections such as the current SARS-CoV2.

METHODS

A critical review of the literature was performed to elucidate the molecular mechanisms and mediators induced by PA that potentially impact on viral infections such as SARS-CoV2.

RESULTS

We showed the effects mediated by regular moderate PA on viral adverse effects through the regulation of biological processes involving the crosstalk between skeletal muscle, the immune system and adipose tissue. Evidence was provided of the effects mediated by modulation of the expression of inflammation markers.

CONCLUSION

A tigth association between PA and reduction in inflammation status allows effective counteracting of SARS-CoV2 infection. It is therefore essential to persuade people to keep active.

Impact of Physical Activity on Cognitive Functions: A New Field for Research and Management of Cystic Fibrosis

Cystic Fibrosis (CF) is a genetic disease inherited by an autosomal recessive mechanism and characterized by a progressive and severe multi-organ failure. Mutations in Cystic Fibrosis Conductance Regulator (CFTR) protein cause duct obstructions from dense mucus secretions and chronic inflammation related to organ damage. The progression of the disease is characterized by a decline of lung function associated with metabolic disorders and malnutrition, musculoskeletal disorders and thoracic deformities, leading to a progressive decrement of the individual’s quality of life. The World Health Organization (WHO) qualifies Physical Activity (PA) as a structured activity produced by skeletal muscles’ movements that requires energy consumption. In the last decade, the number of studies on PA increased considerably, including those investigating the effects of exercise on cognitive and brain health and mental performance. PA is recommended in CF management guidelines, since it improves clinic outcomes, such as peripheral neuropathy, oxygen uptake peak, bone health, glycemic control and respiratory functions. Several studies regarding the positive effects of exercise in patients with Cystic Fibrosis were carried out, but the link between the effects of exercise and cognitive and brain health in CF remains unclear. Animal models showed that exercise might improve learning and memory through structural changes of brain architecture, and such a causal relationship can also be described in humans. Indeed, both morphological and environmental factors seem to be involved in exercise-induced neural plasticity. An increase of gray matter volume in specific areas is detectable as a consequence of regular training in humans. Neurobiological processes associated with brain function improvements include biochemical modifications, such as neuromodulator or neurohormone release, brain-derived neurotrophic factor (BDNF) production and synaptic activity changes. From a functional point of view, PA also seems to be an environmental factor enhancing cognitive abilities, such as executive functions, memory and processing speed. This review describes the current state of research regarding the impacts of physical activity and exercise on cognitive functions, introducing a possible novel field of research for optimizing the management of Cystic Fibrosis.

Molecular Analysis of Prothrombotic Gene Variants in Venous Thrombosis: A Potential Role for Sex and Thrombotic Localization

Background: Requests to test for thrombophilia in the clinical context are often not evidence-based. Aim: To define the role of a series of prothrombotic gene variants in a large population of patients with different venous thromboembolic diseases. Methods: We studied Factor V Leiden (FVL), FVR2, FII G20210A, Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, beta-fibrinogen -455 G>A, FXIII V34L, and HPA-1 L33P variants and PAI-1 4G/5G alleles in 343 male and female patients with deep vein thrombosis (DVT), 164 with pulmonary embolism (PE), 126 with superficial vein thrombosis (SVT), 118 with portal vein thrombosis (PVT), 75 with cerebral vein thrombosis (CVT) and 119 with retinal vein thrombosis (RVT), and compared them with the corresponding variants and alleles in 430 subjects from the general population. Results: About 40% of patients with DVT, PE and SVT had at least one prothrombotic gene variant, such as FVL, FVR2 and FII G20210A, and a statistically significant association with the event was found in males with a history of PE. In patients with a history of PVT or CVT, the FII G20210A variant was more frequent, particularly in females. In contrast, a poor association was found between RVT and prothrombotic risk factors, confirming that local vascular factors have a key role in this thrombotic event. Conclusions: Only FVL, FVR2 and FII G20210A are related to vein thrombotic disease. Other gene variants, often requested for testing in the clinical context, do not differ significantly between cases and controls. Evidence of a sex difference for some variants, once confirmed in larger populations, may help to promote sex-specific prevention of such diseases.

Clinical expression of cystic fibrosis in a large cohort of Italian siblings

Background

A clinical heterogeneity was reported in patients with Cystic Fibrosis (CF) with the same CFTR genotype and between siblings with CF.

Methods

We investigated all clinical aspects in a cohort of 101 pairs of siblings with CF (including 6 triplets) followed since diagnosis.

Results

Severe lung disease had a 22.2% concordance in sib-pairs, occurred early and the FEV₁% at 12 years was predictive of the severity of lung disease in the adulthood. Similarly, CF liver disease occurred early (median: 15 years) and showed a concordance of 27.8% in sib-pairs suggesting a scarce contribution of genetic factors; in fact, only 2/15 patients with liver disease in discordant sib-pairs had a deficiency of alpha-1-antitrypsin (a known modifier gene of CF liver phenotype). CF related diabetes was found in 22 pairs (in 6 in both the siblings). It occurred later (median: 32.5 years) and is strongly associated with liver disease. Colonization by P. aeruginosa and nasal polyposis that required surgery had a concordance > 50% in sib-pairs and were poorly correlated to other clinical parameters. The pancreatic status was highly concordant in pairs of siblings (i.e., 95.1%) but a different pancreatic status was observed in patients with the same CFTR mutations. This suggests a close relationship of the pancreatic status with the “whole” CFTR genotype, including mutations in regulatory regions that may modulate the levels of CFTR expression. Finally, a severe course of CF was evident in a number of patients with pancreatic sufficiency.

Conclusions

Physicians involved in care of patients with CF and in genetic counseling must be aware of the clinical heterogeneity of CF even in sib-pairs that, at the state of the art, is difficult to explain.

Electronic supplementary material

The online version of this article (10.1186/s12890-018-0766-6) contains supplementary material, which is available to authorized users.

Supervised physical exercise improves clinical, anthropometric and biochemical parameters in adult cystic fibrosis patients: A 2-year evaluation

OBJECTIVE

Cystic fibrosis (CF) is the most common inherited, life limiting condition among Caucasians. No healing therapy is currently available for patients with CF. The aim of the study was to define clinical, anthropometric and biochemical effects of regular, supervised physical exercise in a large cohort of patients with CF.

MATERIALS AND METHODS

Fifty-nine adult patients with CF that performed regularly supervised physical exercise in the last 3 years in comparison to 59 sex and age matched sedentary patients with CF were included in the study.

RESULTS

Physical exercise had significantly beneficial effects on: (a) FEV1% decline; (b) anthropometric parameters (lower number of cases with altered BMI, waist and arm circumferences); (c) lipid and glucose metabolism; (d) vitamin D serum levels. Of course, some of this improvement may be because of the better adherence to therapy typical of patients with CF that perform physical activity.

CONCLUSIONS

Such clinical and metabolic effects make supervised physical activity one of the hubs in managing patients with CF.

Butyrate modulating effects on pro-inflammatory pathways in human intestinal epithelial cells

Butyrate acts as energy source for intestinal epithelial cells and as key mediator of several immune processes, modulating gene expression mainly through histone deacetylation inhibition. Thanks to these effects, butyrate has been proposed for the treatment of many intestinal diseases. Aim of this study was to investigate the effect of butyrate on the expression of a large series of target genes encoding proteins involved in pro-inflammatory pathways. We performed quantitative real-time-PCR analysis of the expression of 86 genes encoding proteins bearing to pro-inflammatory pathways, before and after butyrate exposure, in primary epithelial cells derived from human small intestine and colon. Butyrate significantly down-regulated the expression of genes involved in inflammatory response, among which nuclear factor kappa beta, interferon-gamma, Toll like 2 receptor and tumour necrosis factor-alpha. Further confirmations of these data, including studies at protein level, would support the use of butyrate as effective therapeutic strategy in intestinal inflammatory disorders.

Reduced absorption and enhanced synthesis of cholesterol in patients with cystic fibrosis: a preliminary study of plasma sterols

BACKGROUND

Low cholesterol is typically observed in the plasma of patients with cystic fibrosis (CF) contrasting with the subcellular accumulation of cholesterol demonstrated in CF cells and in mice models. However, the homeostasis of cholesterol has not been well investigated in patients with CF.

METHODS

We studied the plasma of 26 patients with CF and 33 unaffected controls campesterol and β-sitosterol as markers of intestinal absorption and lathosterol as a marker of de novo cholesterol biosynthesis by gas chromatography (GC-FID and GC-MS).

RESULTS

Plasma campesterol and β-sitosterol results were significantly (p=0.01) lower while plasma lathosterol was significantly higher (p=0.001) in patients with CF as compared to control subjects. Plasma cholesterol results were significantly lower (p=0.01) in CF patients.

CONCLUSIONS

Our data suggest that the impaired intestinal absorption of exogenous sterols in patients with CF stimulates the endogenous synthesis of cholesterol, but the levels of total cholesterol in plasma remain lower. This may be due to the CFTR dysfunction that reduces cholesterol blood excretion causing the accumulation of cholesterol in liver cells and in other tissues contributing to trigger CF chronic inflammation.

Genotype-phenotype correlation and functional studies in patients with cystic fibrosis bearing CFTR complex alleles

BACKGROUND

The effect of complex alleles in cystic fibrosis (CF) is poorly defined for the lack of functional studies.

OBJECTIVES

To describe the genotype-phenotype correlation and the results of either in vitro and ex vivo studies performed on nasal epithelial cells (NEC) in a cohort of patients with CF carrying cystic fibrosis transmembrane conductance regulator (CFTR) complex alleles.

METHODS

We studied 70 homozygous, compound heterozygous or heterozygous for CFTR mutations: p.[Arg74Trp;Val201Met;Asp1270Asn], n=8; p.[Ile148Thr;Ile1023_Val1024del], n=5; p.[Arg117Leu;Leu997Phe], n=6; c.[1210-34TG[12];1210-12T[5];2930C>T], n=3; p.[Arg74Trp;Asp1270Asn], n=4; p.Asp1270Asn, n=2; p.Ile148Thr, n=6; p.Leu997Phe, n=36. In 39 patients, we analysed the CFTR gating activity on NEC in comparison with patients with CF (n=8) and carriers (n=4). Finally, we analysed in vitro the p.[Arg74Trp;Val201Met;Asp1270Asn] complex allele.

RESULTS

The p.[Ile148Thr;Ile1023_Val1024del] caused severe CF in five compound heterozygous with a class I-II mutation. Their CFTR activity on NEC was comparable with patients with two class I-II mutations (mean 7.3% vs 6.9%). The p.[Arg74Trp;Asp1270Asn] and the p.Asp1270Asn have scarce functional effects, while p.[Arg74Trp;Val201Met;Asp1270Asn] caused mild CF in four of five subjects carrying a class I-II mutation in trans, or CFTR-related disorders (CFTR-RD) in three having in trans a class IV-V mutation. The p.[Arg74Trp;Val201Met;Asp1270Asn] causes significantly (p<0.001) higher CFTR activity compared with compound heterozygous for class I-II mutations. Furthermore, five of six compounds heterozygous with the p.[Arg117Leu;Leu997Phe] had mild CF, whereas the p.Leu997Phe, in trans with a class I-II CFTR mutation, caused CFTR-RD or a healthy status (CFTR activity: 21.3-36.9%). Finally, compounds heterozygous for the c.[1210-34TG[12];1210-12T[5];2930C>T] and a class I-II mutation had mild CF or CFTR-RD (gating activity: 18.5-19.0%).

CONCLUSIONS

The effect of complex alleles partially depends on the mutation in trans. Although larger studies are necessary, the CFTR activity on NEC is a rapid contributory tool to classify patients with CFTR dysfunction.

Extensive molecular analysis suggested the strong genetic heterogeneity of idiopathic chronic pancreatitis

Rationale: Genetic features of Chronic Pancreatitis (CP) have been extensively investigated mainly testing genes associated to the trypsinogen activation pathway. However, different molecular pathways involving other genes may be implicated in CP pathogenesis. Objectives: 80 patients with Idiopathic CP were investigated using Next Generation Sequencing approach with a panel of 70 genes related to six different pancreatic pathways: premature activation of trypsinogen; modifier genes of Cystic Fibrosis phenotype; pancreatic secretion and ion homeostasis; Calcium signalling and zymogen granules exocytosis; autophagy; autoimmune pancreatitis related genes. Results: We detected mutations in 34 out of 70 genes examined; 64/80 patients (80.0%) were positive for mutations in one or more genes, 16/80 patients (20.0%) had no mutations. Mutations in CFTR were detected in 32/80 patients (40.0%) and 22 of them exhibited at least one mutation in genes of other pancreatic pathways. Of the remaining 48 patients, 13/80 (16.3%) had mutations in genes involved in premature activation of trypsinogen and 19/80 (23.8%) had mutations only in genes of the other pathways: 38/64 patients positive for mutations showed variants in two or more genes (59.3%). Conclusions: Our data, although to be extended with functional analysis of novel mutations, suggest a high rate of genetic heterogeneity in chronic pancreatitis and that trans-heterozygosity may predispose to the idiopathic CP phenotype.

AMP18 interacts with the anion exchanger SLC26A3 and enhances its expression in gastric cancer cells

AMP18 is a stomach-specific secreted protein expressed in normal gastric mucosa but absent in gastric cancer. AMP18 plays a major role in maintaining gastric mucosa integrity and is characterized by the presence of a BRICHOS domain consisting of about 100 amino acids, present also in several unrelated proteins, and probably endowed with a chaperon-like activity. In this work, we exploited a functional proteomic strategy to identify potential AMP18 interactors with the aim to add knowledge on its functional role within gastric cell lines and tissues. To this purpose, recombinant biotinylated AMP18 was purified and incubated with protein extract from human normal gastric mucosa by applying an affinity chromatography strategy. The interacting proteins were identified by peptide mass fingerprinting using MALDI-TOF mass spectrometry. The pool of interacting proteins contained SLC26A3, a protein expressed in the apical membrane of intestinal epithelial cells, supposed to play a critical role in Cl(-) absorption and fluid homeostasis. The interaction was also confirmed by Western blot with anti-SLC26A3 on transfected AGS cell extract following AMP18 pull-down. Furthermore, the interaction between AMP18 and SLC26A3 was also validated by confocal microscopy that showed a co-localization of both proteins at plasma membrane level. More importantly, for the first time, we showed that SLC26A3 is down-regulated in gastric cancer and that the overexpression of AMP18 in AMP-transfected gastric cancer cells up-regulated the expression of SLC26A3 both at transcriptional and translational level, the latter probably through the activation of the MAP kinases pathway. These findings strongly suggest that AMP18 might play an anti-inflammatory role in maintaining mucosal integrity also by regulating SLC26A3 level.

Prediction of acute pancreatitis risk based on PIP score in children with cystic fibrosis

BACKGROUND

Currently no tools to predict risk of acute (AP) and recurrent pancreatitis (ARP) in children with cystic fibrosis (CF) are available. We assessed the prevalence of AP/ARP and tested the potential role of Pancreatic Insufficiency Prevalence (PIP) score in a cohort of children with CF.

METHODS

We identified two groups of children, on the basis of presence/absence of AP/ARP, who were compared for age at diagnosis, clinical features, genotypes and sweat chloride level. PIP score was calculated for each patient.

RESULTS

10/167 (5.9%) experienced at least one episode of AP during follow up; 10/10 were pancreatic sufficient (PS). Patients with AP/ARP showed a PIP score ≤0.25 more frequently (6/10) than patients without AP/ARP. The odds ratio (95% CI) of developing pancreatitis was 4.54 (1.22-16.92) for patients with PIP <0.25 when compared with those who have a PIP score >0.25 (p 0.0151). PIP score was correlated with sweat chloride test (p < 0.01).

CONCLUSION

PIP score, PS status and normal/borderline sweat chloride levels could be applied to predict pancreatitis development in children with CF. ARP could lead to pancreatic insufficiency.

Genotype-dependency of butyrate efficacy in children with congenital chloride diarrhea

Background

Congenital chloride diarrhea (CLD) is an autosomal recessive disorder characterized by life-long, severe diarrhea with intestinal Cl^- malabsorption. It results from a reduced activity of the down regulated in adenoma exchanger (DRA), due to mutations in the solute carrier family 26, member 3 (SLC26A3) gene. Currently available therapies are not able to limit the severity of diarrhea in CLD. Conflicting results have been reported on the therapeutic efficacy of oral butyrate.

Methods

We investigated the effect of oral butyrate (100 mg/kg/day) in seven CLD children with different SLC26A3 genotypes. Nasal epithelial cells were obtained to assess the effect of butyrate on the expression of the two main Cl^- transporters: DRA and putative anion transporter-1 (PAT-1).

Results

A variable clinical response to butyrate was observed regarding the stool pattern and fecal ion loss. The best response was observed in subjects with missense and deletion mutations. Variable response to butyrate was also observed on SLC26A3 (DRA) and SLC26A6 (PAT1) gene expression in nasal epithelial cells of CLD patients.

Conclusions

We demonstrate a genotype-dependency for butyrate therapeutic efficacy in CLD. The effect of butyrate is related in part on a different modulation of the expression of the two main apical membrane Cl^- exchangers of epithelial cells, members of the SLC26 anion family.

Trial registration

Australian New Zealand Clinical trial Registry ACTRN12613000450718.

Gene mutation in microRNA target sites of CFTR gene: a novel pathogenetic mechanism in cystic fibrosis?

Cystic fibrosis (CF) is the most frequent lethal genetic disorder among Caucasians. It depends on alterations of a chloride channel expressed by most epithelial cells and encoded by CFTR gene. Also using scanning techniques to analyze the whole coding regions of CFTR gene, mutations are not identified in up to 10% of CF alleles, and such figure increases in CFTR-related disorders (CFTR-RD). Other gene regions may be the site of causing-disease mutations. We searched for genetic variants in the 1500 bp of CFTR 3′ untranslated region, typical target of microRNA (miRNA) posttranscriptional gene regulation, in either CF patients with the F508del homozygous genotype and different clinical expression (n = 20), CF (n = 32) and CFTR-RD (n = 43) patients with one or none mutation after CFTR scanning and in controls (n = 50). We identified three SNPs, one of which, the c.*1043A>C, was located in a region predicted to bind miR-433 and miR-509-3p. Such mutation was peculiar of a CFTR-RD patient that had Congenital Bilateral Absence of Vas Deferens (CBAVD), diffuse bronchiectasis, a borderline sweat chloride test and the heterozygous severe F508del mutation on the other allele. The expression analysis demonstrated that the c.*1043A>C increases the affinity for miR-509-3p and slightly decreases that for the miR-433. Both miRNAs cause in vitro a reduced expression of CFTR protein. Thus, the c.*1043A>C may act as a mild CFTR mutation enhancing the affinity for inhibitory miRNAs as a novel pathogenetic mechanism in CF.

Molecular and functional analysis of the large 5' promoter region of CFTR gene revealed pathogenic mutations in CF and CFTR-related disorders

Patients with cystic fibrosis (CF) manifest a multisystemic disease due to mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR); despite extensive testing of coding regions, a proportion of CF alleles remains unidentified. We studied 118 patients with CF and CFTR-related disorders, most with one or both unknown mutations after the scanning of CFTR coding regions, and a non-CF control group (n = 75) by sequencing the 6000-bp region at the 5' of the CFTR gene. We identified 23 mutations, of which 9 were novel. We expressed such mutations in vitro using four cell systems to explore their functional effect, relating the data to the clinical expression of each patient. Some mutations reduced expression of the gene reporter firefly luciferase in various cell lines and may act as disease-causing mutations. Other mutations caused an increase in luciferase expression in some cell lines. One mutation had a different effect in different cells. For other mutations, the expression assay excluded a functional role. Gene variants in the large 5' region may cause altered regulation of CFTR gene expression, acting as disease-causing mutations or modifiers of its clinical phenotype. Studies of in vitro expression in different cell systems may help reveal the effect of such mutations.

Extensive molecular analysis of patients bearing CFTR-related disorders

Cystic fibrosis transmembrane conductance regulator (CFTR)-related disorders (CFTR-RDs) may present with pancreatic sufficiency, normal sweat test results, and better outcome. The detection rate of mutations is lower in CFTR-RD than in classic CF: mutations may be located in genes encoding proteins that interact with CFTR or support channel activity. We tested the whole CFTR coding regions in 99 CFTR-RD patients, looking for gene mutations in solute carrier (SLC) 26A and in epithelial Na channel (ENaC) in 33 patients who had unidentified mutations. CFTR analysis revealed 28 mutations, some of which are rare. Of these mutations, RT-PCR demonstrated that the novel 1525-1delG impairs exon 10 splicing; by using minigene analysis, we excluded the splicing effect of three other novel intronic variants. Analysis of SLC26A genes revealed several variants, some of which are novel, that did not affect mRNA expression. Other mutations occurred in the ENaC genes encoding the ENaC subunits, but their frequency did not significantly differ between patients and controls. Our data, although obtained on a preliminary cohort of CFTR-RD patients, exclude a role of mutations in SLC26A and in SCNN genes in the pathogenesis of such disease; we confirm that CFTR analysis has a relevant role in CFTR-RD patients; and it appears mandatory to use CFTR scanning techniques and approaches to reveal the effect of novel mutations.

A novel DHPLC-based procedure for the analysis of COL1A1 and COL1A2 mutations in osteogenesis imperfecta

Approximately 90% of patients with osteogenesis imperfecta (OI) exhibit dominant COL1A1 or COL1A2 mutations; however, molecular analysis is difficult because these genes span 51 and 52 exons, respectively. We devised a PCR-denaturing high-performance liquid chromatography (DHPLC) procedure to analyze the COL1A1 or COL1A2 coding regions and validated it using 130 DNA samples from individuals without OI, 25 DNA samples from two cells to investigate the procedure's potential for preimplantation diagnosis, and DNA samples from 10 patients with OI. Three novel intronic variants in vitro were expressed using a minigene assay to assess their effects on splicing. The procedure is rapid, inexpensive, and reproducible. Analysis of samples from individuals without OI revealed six novel and some known polymorphisms useful for linkage diagnosis because of high heterozygosity. Analysis of two-cell samples confirmed the known genotype in 24 of 25 experiments; DNA failed to amplify in only one case. No incidence of allele dropout was recorded. DHPLC revealed six novel mutations, three of which were intronic, in all patients with OI, and these results were confirmed by means of COL1A1 and COL1A2 direct sequencing. Expression of intronic mutations demonstrated that variant 804 + 2_804 + 3delTG in intron 11 disrupts normal splicing, thereby leading to formation of two alternative products. Variants c.3046-4_3046-5dupCT (COL1A1) and c.891 + 77A>T (COL1A2) did not affect splicing. The described DHPLC protocol combined with the minigene assay may contribute to molecular diagnosis in OI. Moreover, this protocol will aid in counseling about prenatal and preimplantation diagnosis.

Enhanced frequency of CFTR gene variants in couples who are candidates for assisted reproductive technology treatment

BACKGROUND

An increased frequency of (cystic fibrosis transmembrane conductance regulator) CFTR mutations has been detected in some types of male infertility. The aim of this study was to shed light on the link between CFTR mutations and infertility.

METHODS

We sequenced the CFTR gene in 294 subjects (190 males) affected by infertility of different origin who underwent assisted reproductive technology (ART). As a control group, we studied 1000 (353 males) unrelated, unselected subjects from the general population of southern Italy.

RESULTS

The frequency of CFTR mutations, some of which are detected only by gene sequencing, and of the IVS8 poly(TG)12-poly(T)5-V470 haplotype was significantly higher in obstructive [congenital bilateral absence of vasa defer-entes (CBAVD, five cases)] and secretory (23 cases) azoospermic patients than in the general population. Some patients, primarily those with CBAVD, were compound heterozygous for two mutations. Interestingly, the frequency of the TG12-T5-V470 variant haplotype was significantly higher in severe oligospermic patients (88 cases) and in patients with tubal sterility (74 cases) compared with the general population. Finally, neither the frequency of CFTR mutations nor the frequency of the TG12-T5 variants differed between patients with mild oligospermia (74 cases) and patients with ovulatory sterility (30 cases) compared with the general population.

CONCLUSIONS

All subjects affected by obstructive or secretory azoospermia should undergo molecular analysis and counselling for CF using gene scanning which has a high detection rate and also reveals rare CFTR mutations. Molecular analysis seems to be less mandatory in other types of male/female infertility. Furthermore, we found that the CFTR TG12-T5-V470 variant haplotype was associated with both severe oligospermia and tubal infertility, thereby implicating the CFTR protein in both spermatogenesis and tubal functionality.

Three novel CFTR polymorphic repeats improve segregation analysis for cystic fibrosis

BACKGROUND

Molecular diagnosis for cystic fibrosis (CF) is based on the direct identification of mutations in the CFTR gene [cystic fibrosis transmembrane conductance regulator (ATP-binding cassette sub-family C, member 7)] (detection rate about 90% with scanning procedures) and on segregation analysis of intragenic polymorphisms for carrier and prenatal diagnosis in about 20% of CF families in which 1 or both causal mutations are unknown.

METHODS

We identified 3 novel intragenic polymorphic repeats (IVS3polyA, IVS4polyA, and IVS10CA repeats) in the CFTR gene and developed and validated a procedure based on the PCR followed by capillary electrophoresis for large-scale analysis of these polymorphisms and the 4 previously identified microsatellites (IVS1CA, IVS8CA, IVS17bTA, and IVS17bCA repeats) in a single run. We validated the procedure for both single- and 2-cell samples (for a possible use in preimplantation diagnosis), and on a large number of CF patients bearing different genotypes and non-CF controls.

RESULTS

The allelic distribution and heterozygosity results suggest that the 3 novel polymorphisms strongly contribute to carrier and prenatal diagnosis of CF in families in which 1 or both causal mutations have not been identified. At least 1 of the 4 previously identified microsatellites was informative in 78 of 100 unrelated CF families; at least 1 of all 7 polymorphisms was informative in 98 of the families. Finally, the analysis of haplotypes for the 7 polymorphisms revealed that most CF mutations are associated with different haplotypes, suggesting multiple slippage events but a single origin for most CFTR mutations.

CONCLUSIONS

The analysis of the 7 polymorphisms is a rapid and efficient tool for routine carrier, prenatal, and preimplantation diagnosis of CF.

Isolated elevated sweat chloride concentrations in the presence of the rare mutation S1455X: An extremely mild form ofCFTR dysfunction

Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) have been shown to cause typical cystic fibrosis (CF) and several milder phenotypes. We report on two asymptomatic sisters who had isolated increased sweat chloride concentrations, and in whom systematic scanning of the whole coding region of the CFTR gene revealed the F508del/S1455X genotype.