Pseudomonas aeruginosa Trent and zinc homeostasis.

FEMS Microbiol Lett. 2017 Sep 01;364(16):

Authors: Davies CB, Harrison MD, Huygens F

Abstract
Pseudomonas aeruginosa is a Gram-negative pathogen and the major cause of mortality in patients with cystic fibrosis. The mechanisms that P. aeruginosa strains use to regulate intracellular zinc have an effect on infection, antibiotic resistance and the propensity to form biofilms. However, zinc homeostasis in P. aeruginosa strains of variable infectivity has not been compared. In this study, zinc homeostasis in P. aeruginosa Trent, a highly infectious clinical strain, was compared to that of a laboratory P. aeruginosa strain, ATCC27853. Trent was able to tolerate higher concentrations of additional zinc in rich media than ATCC27853. Further, pre-adaptation to additional zinc enhanced the growth of Trent at non-inhibitory concentrations but the impact of pre-adaption on the growth of ATCC27853 under the same conditions was minimal. The results establish clear differences in zinc-induced responses in Trent and ATCC27853, and how zinc homeostasis can be a promising target for the development of novel antimicrobial strategies for P. aeruginosa infection in cystic fibrosis patients.

PMID: 28854710 [PubMed - in process]

Current and future therapies for Pseudomonas aeruginosa infection in patients with cystic fibrosis.

FEMS Microbiol Lett. 2017 Aug 01;364(14):

Authors: Smith WD, Bardin E, Cameron L, Edmondson CL, Farrant KV, Martin I, Murphy RA, Soren O, Turnbull AR, Wierre-Gore N, Alton EW, Bundy JG, Bush A, Connett GJ, Faust SN, Filloux A, Freemont PS, Jones AL, Takats Z, Webb JS, Williams HD, Davies JC

Abstract
Pseudomonas aeruginosa opportunistically infects the airways of patients with cystic fibrosis and causes significant morbidity and mortality. Initial infection can often be eradicated though requires prompt detection and adequate treatment. Intermittent and then chronic infection occurs in the majority of patients. Better detection of P. aeruginosa infection using biomarkers may enable more successful eradication before chronic infection is established. In chronic infection P. aeruginosa adapts to avoid immune clearance and resist antibiotics via efflux pumps, β-lactamase expression, reduced porins and switching to a biofilm lifestyle. The optimal treatment strategies for P. aeruginosa infection are still being established, and new antibiotic formulations such as liposomal amikacin, fosfomycin in combination with tobramycin and inhaled levofloxacin are being explored. Novel agents such as the alginate oligosaccharide OligoG, cysteamine, bacteriophage, nitric oxide, garlic oil and gallium may be useful as anti-pseudomonal strategies, and immunotherapy to prevent infection may have a role in the future. New treatments that target the primary defect in cystic fibrosis, recently licensed for use, have been associated with a fall in P. aeruginosa infection prevalence. Understanding the mechanisms for this could add further strategies for treating P. aeruginosa in future.

PMID: 28854668 [PubMed - in process]

Airway Mucosal Host Defense is Key to Genomic Regulation of Cystic Fibrosis Lung Disease Severity.

Am J Respir Crit Care Med. 2017 Aug 30;:

Authors: Polineni D, Dang H, Gallins PJ, Jones LC, Pace RG, Stonebraker JR, Commander LA, Krenicky JE, Zhou YH, Corvol H, Cutting GR, Drumm ML, Strug LJ, Boyle MP, Durie PR, Chmiel JF, Zou F, Wright FA, O'Neal WK, Knowles MR

Abstract
RATIONALE: The severity of cystic fibrosis (CF) lung disease varies widely, even for Phe508del homozygotes. Heritability studies show that >50% of the variability reflects non-CFTR genetic variation; however the full extent of the pertinent genetic variation is not known.
OBJECTIVES: We sought to identify novel CF disease-modifying mechanisms using an integrated approach based on analyzing "in vivo" CF airway epithelial gene expression, complemented with genome-wide association study (GWAS) data.
METHODS: Nasal mucosal RNA from 134 CF patients was used for RNA sequencing. We tested for associations of transcriptomic (gene expression) data with a quantitative phenotype of CF lung disease severity. Pathway analysis of CF GWAS data (n = 5,659 patients) was performed to identify novel pathways and assess concordance of genomic and transcriptomic data. Association of gene expression with previously identified CF GWAS risk alleles was also tested.
MEASUREMENTS AND MAIN RESULTS: Significant evidence of heritable gene expression was identified. Gene expression pathways relevant to airway mucosal host defense were significantly associated with CF lung disease severity, including viral infection, inflammation/inflammatory signaling, lipid metabolism, apoptosis, ion transport, Phe508del CFTR processing, and innate immune responses, including HLA genes. Ion transport and CFTR processing pathways, and HLA genes, were identified across differential gene expression and GWAS signals.
CONCLUSION: Transcriptomic analyses in CF airway epithelia, coupled to genomic (GWAS) analyses, highlights the role of heritable host defense variation in determining the pathophysiology of CF lung disease. The identification of these pathways provides opportunities to pursue targeted interventions to improve CF lung health.

PMID: 28853905 [PubMed - as supplied by publisher]

Clinical trial research in focus: ensuring new cystic fibrosis drugs fulfil their potential.

Lancet Respir Med. 2017 Sep;5(9):681-683

Authors: Elborn JS, Davies J

PMID: 28853396 [PubMed - in process]

Eigenvalue significance testing for genetic association.

Biometrics. 2017 Aug 29;:

Authors: Zhou YH, Marron JS, Wright FA

Abstract
Genotype eigenvectors are widely used as covariates for control of spurious stratification in genetic association. Significance testing for the accompanying eigenvalues has typically been based on a standard Tracy-Widom limiting distribution for the largest eigenvalue, derived under white-noise assumptions. It is known that even modest local correlation among markers inflates the largest eigenvalues, even in the absence of true stratification. In addition, a few sample eigenvalues may be extreme, creating further complications in accurate testing. We explore several methods to identify appropriate null eigenvalue thresholds, while remaining sensitive to eigenvalues corresponding to population stratification. We introduce a novel block permutation approach, designed to produce an appropriate null eigenvalue distribution by eliminating long-range genomic correlation while preserving local correlation. We also propose a fast approach based on eigenvalue distribution modeling, using a simple fit criterion and the general Marčenko-Pastur equation under a simple discrete eigenvalue model. Block permutation and the model-based approach work well for pure simulations and for data resampled from the 1000 Genomes project. In contrast, we find that the standard approach of computing an "effective" number of markers does not perform well. The performance of the methods is also demonstrated for a motivating example from the International Cystic Fibrosis Consortium.

PMID: 28853138 [PubMed - as supplied by publisher]

Early severe anemia as the first sign of cystic fibrosis.

Eur J Pediatr. 2017 Aug 30;:

Authors: Aricò MOLR, Ielo S, Palma L, Maschio M, Lubrano L, Pietrobelli A, Degani D, D'Orazio C

PMID: 28852771 [PubMed - as supplied by publisher]

The Sweat Metabolome of Screen-Positive Cystic Fibrosis Infants: Revealing Mechanisms beyond Impaired Chloride Transport.

ACS Cent Sci. 2017 Aug 23;3(8):904-913

Authors: Macedo AN, Mathiaparanam S, Brick L, Keenan K, Gonska T, Pedder L, Hill S, Britz-McKibbin P

Abstract
The sweat chloride test remains the gold standard for confirmatory diagnosis of cystic fibrosis (CF) in support of universal newborn screening programs. However, it provides ambiguous results for intermediate sweat chloride cases while not reflecting disease progression when classifying the complex CF disease spectrum given the pleiotropic effects of gene modifiers and environment. Herein we report the first characterization of the sweat metabolome from screen-positive CF infants and identify metabolites associated with disease status that complement sweat chloride testing. Pilocarpine-stimulated sweat specimens were collected independently from two CF clinics, including 50 unaffected infants (e.g., carriers) and 18 confirmed CF cases. Nontargeted metabolite profiling was performed using multisegment injection-capillary electrophoresis-mass spectrometry as a high throughput platform for analysis of polar/ionic metabolites in volume-restricted sweat samples. Amino acids, organic acids, amino acid derivatives, dipeptides, purine derivatives, and unknown exogenous compounds were identified in sweat when using high resolution tandem mass spectrometry, including metabolites associated with affected yet asymptomatic CF infants, such as asparagine and glutamine. Unexpectedly, a metabolite of pilocarpine, used to stimulate sweat secretion, pilocarpic acid, and a plasticizer metabolite from environmental exposure, mono(2-ethylhexyl)phthalic acid, were secreted in the sweat of CF infants at significantly lower concentrations relative to unaffected CF screen-positive controls. These results indicated a deficiency in human paraoxonase, an enzyme unrelated to mutations to the cystic fibrosis transmembrane conductance regulator (CFTR) and impaired chloride transport, which is a nonspecific arylesterase/lactonase known to mediate inflammation, bacterial biofilm formation, and recurrent lung infections in affected CF children later in life. This work sheds new light into the underlying mechanisms of CF pathophysiology as required for new advances in precision medicine of orphan diseases that benefit from early detection and intervention, including new molecular targets for therapeutic intervention.

PMID: 28852705 [PubMed]

Weight gain during acute treatment of an initial pulmonary exacerbation is associated with a longer interval to the next exacerbation in adults with cystic fibrosis.

ERJ Open Res. 2017 Jul;3(3):

Authors: Barr HL, Cámara M, Barrett D, Williams P, Forrester D, Smyth A, Honeybourne D, Whitehouse J, Nash E, Dewar J, Knox A, Fogarty AW

Abstract
Weight gain during treatment for a cystic fibrosis exacerbation http://ow.ly/f1zl30dU9AO.

PMID: 28852645 [PubMed]

Mapping genetic determinants of host susceptibility to Pseudomonas aeruginosa lung infection in mice.

BMC Genomics. 2016 May 11;17:351

Authors: De Simone M, Spagnuolo L, Lorè NI, Cigana C, De Fino I, Broman KW, Iraqi FA, Bragonzi A

Abstract
BACKGROUND: P. aeruginosa is one of the top three causes of opportunistic human bacterial infections. The remarkable variability in the clinical outcomes of this infection is thought to be associated with genetic predisposition. However, the genes underlying host susceptibility to P. aeruginosa infection are still largely unknown.
RESULTS: As a step towards mapping these genes, we applied a genome wide linkage analysis approach to a mouse model. A large F2 intercross population, obtained by mating P. aeruginosa-resistant C3H/HeOuJ, and susceptible A/J mice, was used for quantitative trait locus (QTL) mapping. The F2 progenies were challenged with a P. aeruginosa clinical strain and monitored for the survival time up to 7 days post-infection, as a disease phenotype associated trait. Selected phenotypic extremes of the F2 distribution were genotyped with high-density single nucleotide polymorphic (SNP) markers, and subsequently QTL analysis was performed. A significant locus was mapped on chromosome 6 and was named P . aeruginosa infection resistance locus 1 (Pairl1). The most promising candidate genes, including Dok1, Tacr1, Cd207, Clec4f, Gp9, Gata2, Foxp1, are related to pathogen sensing, neutrophils and macrophages recruitment and inflammatory processes.
CONCLUSIONS: We propose a set of genes involved in the pathogenesis of P. aeruginosa infection that may be explored to complement human studies.

PMID: 27169516 [PubMed - indexed for MEDLINE]

Dual device cannulation of an intradiverticular minor papilla.

Gastrointest Endosc. 2016 Sep;84(3):530-1

Authors: Amateau SK, Freeman ML

PMID: 27032882 [PubMed - indexed for MEDLINE]

Oxygen-dependent regulation of c-di-GMP synthesis by SadC controls alginate production in Pseudomonas aeruginosa.

Environ Microbiol. 2016 Oct;18(10):3390-3402

Authors: Schmidt A, Hammerbacher AS, Bastian M, Nieken KJ, Klockgether J, Merighi M, Lapouge K, Poschgan C, Kölle J, Acharya KR, Ulrich M, Tümmler B, Unden G, Kaever V, Lory S, Haas D, Schwarz S, Döring G

Abstract
Pseudomonas aeruginosa produces increased levels of alginate in response to oxygen-deprived conditions. The regulatory pathway(s) that links oxygen limitation to increased synthesis of alginate has remained elusive. In the present study, using immunofluorescence microscopy, we show that anaerobiosis-induced alginate production by planktonic PAO1 requires the diguanylate cyclase (DGC) SadC, previously identified as a regulator of surface-associated lifestyles. Furthermore, we found that the gene products of PA4330 and PA4331, located in a predicted operon with sadC, have a major impact on alginate production: deletion of PA4330 (odaA, for oxygen-dependent alginate synthesis activator) caused an alginate production defect under anaerobic conditions, whereas a PA4331 (odaI, for oxygen-dependent alginate synthesis inhibitor) deletion mutant produced alginate also in the presence of oxygen, which would normally inhibit alginate synthesis. Based on their sequence, OdaA and OdaI have predicted hydratase and dioxygenase reductase activities, respectively. Enzymatic assays using purified protein showed that unlike OdaA, which did not significantly affect DGC activity of SadC, OdaI inhibited c-di-GMP production by SadC. Our data indicate that SadC, OdaA and OdaI are components of a novel response pathway of P. aeruginosa that regulates alginate synthesis in an oxygen-dependent manner.

PMID: 26743546 [PubMed - indexed for MEDLINE]

Histones bundle F-actin filaments and affect actin structure.

PLoS One. 2017;12(8):e0183760

Authors: Blotnick E, Sol A, Muhlrad A

Abstract
Histones are small polycationic proteins complexed with DNA located in the cell nucleus. Upon apoptosis they are secreted from the cells and react with extracellular polyanionic compounds. Actin which is a polyanionic protein, is also secreted from necrotic cells and interacts with histones. We showed that both histone mixture (histone type III) and the recombinant H2A histone bundles F-actin, increases the viscosity of the F-actin containing solution and polymerizes G-actin. The histone-actin bundles are relatively insensitive to increase of ionic strength, unlike other polycation, histatin, lysozyme, spermine and LL-37 induced F-actin bundles. The histone-actin bundles dissociate completely only in the presence of 300-400 mM NaCl. DNA, which competes with F-actin for histones, disassembles histone induced actin bundles. DNase1, which depolymerizes F- to G-actin, actively unbundles the H2A histone induced but slightly affects the histone mixture induced actin bundles. Cofilin decreases the amount of F-actin sedimented by low speed centrifugation, increases light scattering and viscosity of F-actin-histone mixture containing solutions and forms star like superstructures by copolymerizing G-actin with H2A histone. The results indicate that histones are tightly attached to F-actin by strong electrostatic and hydrophobic forces. Since both histones and F-actin are present in the sputum of patients with cystic fibrosis, therefore, the formation of the stable histone-actin bundles can contribute to the pathology of this disease by increasing the viscosity of the sputum. The actin-histone interaction in the nucleus might affect gene expression.

PMID: 28846729 [PubMed - in process]

Transcriptomic profile of cystic fibrosis patients identifies type I interferon response and ribosomal stalk proteins as potential modifiers of disease severity.

PLoS One. 2017;12(8):e0183526

Authors: Kormann MSD, Dewerth A, Eichner F, Baskaran P, Hector A, Regamey N, Hartl D, Handgretinger R, Antony JS

Abstract
Cystic Fibrosis (CF) is the most common monogenic disease among people of Western European descent and caused by mutations in the CFTR gene. However, the disease severity is immensely variable even among patients with similar CFTR mutations due to the possible effect of 'modifier genes'. To identify genetic modifiers, we applied RNA-seq based transcriptomic analyses in CF patients with a mild and severe lung phenotype. Global gene expression and enrichment analyses revealed that genes of the type I interferon response and ribosomal stalk proteins are potential modifiers of CF related lung dysfunction. The results provide a new set of CF modifier genes with possible implications as new therapeutic targets for the treatment of CF.

PMID: 28846703 [PubMed - in process]

The safety of lumacaftor and ivacaftor for the treatment of cystic fibrosis.

Expert Opin Drug Saf. 2017 Aug 28;:

Authors: Talamo Guevara M, McColley SA

Abstract
INTRODUCTION: Lumacaftor-ivacaftor is indicated for treatment of cystic fibrosis (CF) in patients homozygous for the Phe-508del cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations. In clinical trials, treated patients showed improved pulmonary function, reduced pulmonary exacerbations, and other benefits. This article reviews safety of this therapy. Areas covered: Safety findings in ivacaftor, lumacaftor and combined therapy trials, and reported subsequently through post-approval evaluation, were accessed by PubMed and Google searches using key words "VX-770", "ivacaftor", "VX-809", and "lumacaftor". Transaminitis was seen in ivacaftor and combination trials. Non-congenital cataracts were seen in pre-clinical animal studies and in children taking ivacaftor and combined therapy. Dyspnea occurs in some patients taking lumacaftor and combined therapy and usually resolves without stopping treatment. Lumacaftor is a strong inducer of CYP3A while ivacaftor is a CYP3A sensitive substrate. Combination therapy can decrease systemic exposure of medications that are substrates of CYP3A, decreasing therapeutic effect. Co-administration of lumacaftor-ivacaftor with sensitive CYP3A substrates or CYP3A substrates with narrow therapeutic index is not recommended. Expert opinion: Lumacaftor-ivacaftor therapy may be associated with ocular and hepatic side effects. Specific recommendations for monitoring are available. Dyspnea occurs, especially during initiation of treatment. Potential drug interactions should be evaluated in patients taking combination therapy. The risk benefit ratio of lumacaftor-ivacaftor favors therapy.

PMID: 28846049 [PubMed - as supplied by publisher]

[Rare diseases in post-genomic era.]

Recenti Prog Med. 2017 Jul-Aug;108(7):307-315

Authors: Pulciani S, Vittozzi A, Diemoz S, Nutile E, Taruscio D

Abstract
The Human Genome Project and the "-omics" technologies will in future provide genetic maps and biosynthetic pathways permitting personalized medical interventions directed at maintaining or restoring wellbeing. This is reflected in the strategy aims of 4P medicine in being: predictive, preventive, personalized, and participatory. The results obtained in the field of cystic fibrosis, with the cloning of CFTR gene, and use of Kalydeco®, have demonstrated how using the mentioned strategies could also have success in rare disease management. Kalydeco® is the emblematic example demonstrating the indispensable role of an active patient participation in fully achieving the P4 medicine goals. It is actually the patient involvement that will furnish the fundamental data necessary in defining molecular profiles specific to the health status of any patient. These molecular profiles will contribute in planning preventive, and/or therapeutic interventions aimed at maintaining, and/or restoring the health conditions. Hence, for a correct and effective implementation of P4 medicine, researchers and healthcare professionals should always consider the psychological experiences and characteristics of their patients and families; making them all participants in formulating an appropriate therapeutic path. In achieving this, it will not only be necessary to consider and use concepts of vulnerability and resilience, particularly in the rare disease field, where patient fragility is high, and caregivers are often faced with unique and difficult issues, never confronted before.

PMID: 28845852 [PubMed - in process]

Sensitive Monogenic Noninvasive Prenatal Diagnosis by Targeted Haplotyping.

Am J Hum Genet. 2017 Aug 18;:

Authors: Vermeulen C, Geeven G, de Wit E, Verstegen MJAM, Jansen RPM, van Kranenburg M, de Bruijn E, Pulit SL, Kruisselbrink E, Shahsavari Z, Omrani D, Zeinali F, Najmabadi H, Katsila T, Vrettou C, Patrinos GP, Traeger-Synodinos J, Splinter E, Beekman JM, Kheradmand Kia S, Te Meerman GJ, Ploos van Amstel HK, de Laat W

Abstract
During pregnancy, cell-free DNA (cfDNA) in maternal blood encompasses a small percentage of cell-free fetal DNA (cffDNA), an easily accessible source for determination of fetal disease status in risk families through non-invasive procedures. In case of monogenic heritable disease, background maternal cfDNA prohibits direct observation of the maternally inherited allele. Non-invasive prenatal diagnostics (NIPD) of monogenic diseases therefore relies on parental haplotyping and statistical assessment of inherited alleles from cffDNA, techniques currently unavailable for routine clinical practice. Here, we present monogenic NIPD (MG-NIPD), which requires a blood sample from both parents, for targeted locus amplification (TLA)-based phasing of heterozygous variants selectively at a gene of interest. Capture probes-based targeted sequencing of cfDNA from the pregnant mother and a tailored statistical analysis enables predicting fetal gene inheritance. MG-NIPD was validated for 18 pregnancies, focusing on CFTR, CYP21A2, and HBB. In all cases we could predict the inherited alleles with >98% confidence, even at relatively early stages (8 weeks) of pregnancy. This prediction and the accuracy of parental haplotyping was confirmed by sequencing of fetal material obtained by parallel invasive procedures. MG-NIPD is a robust method that requires standard instrumentation and can be implemented in any clinic to provide families carrying a severe monogenic disease with a prenatal diagnostic test based on a simple blood draw.

PMID: 28844486 [PubMed - as supplied by publisher]

Molecular epidemiology of Pseudomonas aeruginosa in an unsegregated bronchiectasis cohort sharing hospital facilities with a cystic fibrosis cohort.

Thorax. 2017 Aug 26;:

Authors: Mitchelmore PJ, Randall J, Bull MJ, Moore KA, O'Neill PA, Paszkiewicz K, Mahenthiralingam E, Scotton CJ, Sheldon CD, Withers NJ, Brown AR

Abstract
While Pseudomonas aeruginosa (PA) cross-infection is well documented among patients with cystic fibrosis (CF), the equivalent risk among patients with non-CF bronchiectasis (NCFB) is unclear, particularly those managed alongside patients with CF. We performed analysis of PA within a single centre that manages an unsegregated NCFB cohort alongside a segregated CF cohort. We found no evidence of cross-infection between the two cohorts or within the segregated CF cohort. However, within the unsegregated NCFB cohort, evidence of cross-infection was found between three (of 46) patients. While we do not presently advocate any change in the management of our NCFB cohort, longitudinal surveillance is clearly warranted.

PMID: 28844058 [PubMed - as supplied by publisher]

Clinical and microbiological profile of chronic Burkholderia cepacia complex infections in a cystic fibrosis reference hospital in Brazil.

Eur J Clin Microbiol Infect Dis. 2017 Aug 24;:

Authors: da Costa Capizzani CP, Caçador NC, Torres LAGMM, Tonani L, Vandamme P, da Costa Darini AL

Abstract
Burkholderia sp. infections are extremely complex in cystic fibrosis (CF) patients, especially considering the lack of knowledge regarding its behavior, its relationship with prognosis, as well as its transmissibility and multidrug resistance features. This study evaluated the frequency of chronic infection by Burkholderia, using microbiological and clinical data. Ninety-eight patients with CF attended from July 2011 to April 2014 in a Brazilian reference hospital were included. Antimicrobial activity, molecular epidemiology, Shwachman score, body mass index, exacerbations, and lung function were analyzed. Nine patients had chronic colonization, and all of them showed preserved pulmonary function levels, body mass index, and Shwachman score. Meropenem was the most effective antibiotic; however, divergent results were shown by other studies. Cross-contamination may have occurred in only two unrelated patients of different ages, who were colonized by B. vietnamiensis, which does not occur frequently. Twelve new sequence types (STs) were identified and three STs have presented intercontinental distribution. None of the patients presented known epidemic strains. In conclusion, a relatively low number of patients with chronic colonization and suspected cross-infection were identified. Different from other studies that have found CF patients chronically colonized with Burkholderia sp. having a greater deterioration of lung function, more frequent antibiotic therapy, and increased mortality, in the current study, the patients showed good clinical outcomes and favorable options for antibiotics therapy. This study also updated the epidemiological database, which facilitates the multicentric collaborative analysis and assists in the control of global infection by these pathogens.

PMID: 28840370 [PubMed - as supplied by publisher]

Changes in magnetic resonance imaging scores and ventilation inhomogeneity in children with cystic fibrosis pulmonary exacerbations.

Eur Respir J. 2017 Aug;50(2):

Authors: Grasemann H, Ciet P, Amin R, McDonald N, Klingel M, Tiddens HAWM, Ratjen F, Grosse-Wortmann L

PMID: 28838978 [PubMed - in process]

Combinatorial effects of quercetin and sex-steroids on fluid and electrolytes' (Na+, Cl-, HCO3-) secretory mechanisms in the uterus of ovariectomised female Sprague-Dawley rats.

PLoS One. 2017;12(3):e0172765

Authors: Shahzad H, Giribabu N, Karim K, Kassim NM, Muniandy S, Salleh N

Abstract
Dysregulation of uterine fluid environment could impair successful reproduction and this could be due to the effect of environmental estrogens. Therefore, in this study, effect of quercetin, an environmental estrogen on uterine fluid and electrolytes concentrations were investigated under sex-steroid influence. Ovariectomised adult female Sprague-Dawley rats were given 10, 50 or 100mg/kg/day quercetin subcutaneously with 17-β estradiol (E) for seven days or three days E, then three days E plus progesterone (P) (E+P) treatment. Uterine fluid secretion rate, Na+, Cl- and HCO3- concentrations were determined by in-vivo perfusion. Following sacrifice, uteri were harvested and levels of the proteins of interest were identified by Western blotting and Realtime PCR. Distribution of these proteins in the uterus was observed by immunofluorescence. Levels of uterine cAMP were measured by enzyme-linked immunoassay (EIA). Administration of quercetin at increasing doses increased uterine fluid secretion rate, Na+, Cl- and HCO3- concentrations, but to the levels lesser than that of E. In concordant, levels of CFTR, SLC4A4, ENaC (α, β and γ), Na+/K+-ATPase, GPα/β, AC and cAMP in the uterus increased following increased in the doses of quercetin. Co-administration of quercetin with E caused uterine fluid secretion rate, Na+, Cl- and HCO3- concentrations to decrease. In concordant, uterine CFTR, SLC26A6, SLC4A4, ENaC (α, β and γ), Na+/K+-ATPase, GPα/β, AC and cAMP decreased. Greatest effects were observed following co-administration of 10mg/kg/day quercetin with E. Co-administration of quercetin with E+P caused uterine fluid Na+ and HCO3- concentrations to increase but no changes in fluid secretion rate and Cl- concentration were observed. Co-administration of high dose quercetin (100 mg/kg/day) with E+P caused uterine CFTR, SLC26A6, AC, GPα/β and ENaC (α, β and γ) to increase. Quercetin-induced changes in the uterine fluid secretion rate and electrolytes concentrations could potentially affect the uterine reproductive functions under female sex-steroid influence.

PMID: 28253299 [PubMed - indexed for MEDLINE]