1330. Stabilized PLASmin® Complexes Deliver Exogenous Genes to the Nasal Epithelia of Cystic Fibrosis (CF) Knockout Mice and Confer Partial Physiological Correction of CFTR-Mediated Chloride Transport

ABSTRACT In cystic fibrosis, a recessive genetic disease caused by defects in the cystic fibrosis conductance regulator (CFTR), the main cause of death is lung infection and inflammation. Nutritional deficits have been proposed to contribute to the excessive host inflammatory response in both humans and Cftr-knockout mice. Cftr-knockout mice and gut-corrected Cftr-knockout mice expressing human CFTR primarily in the gut were challenged with Pseudomonas aeruginosa-laden agarose beads; they responded similarly with respect to bronchoalveolar lavage cell counts and levels of the acute-phase cytokines tumor necrosis factor alpha, interleukin-1β (IL-1β), and IL-6. Wild-type mice fed the liquid diet used to prevent intestinal obstruction in Cftr-knockout mice had inflammatory responses to P. aeruginosa-laden agarose beads similar to those of wild-type mice fed an enriched solid diet, so dietary effects are unlikely to account for differences between wild-type mice and mice with cystic fibrosis. Finally, since cystic fibrosis patients and Cftr-knockout mice have an imbalance in fatty acids (significantly lower-than-normal levels of docosahexaenoic acid), the effects of specific supplementation with docosahexaenoic acid of wild-type and Cftr-knockout mice on their inflammatory responses to P. aeruginosa-laden agarose beads were tested. There were no significant differences (P = 0.35) in cumulative survival rates between Cftr-knockout mice and wild-type mice provided with either the liquid diet Peptamen or Peptamen containing docosahexaenoic acid. In conclusion, diet and docosahexaenoic acid imbalances alone are unlikely to explain the differences in the host response to lung infections with mucoid P. aeruginosa between mice with cystic fibrosis and their wild-type counterparts.

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Altered intestinal chloride transport in cystic fibrosis

The FASEB Journal ◽

10.1096/fasebj.2.10.2838365 ◽

1988 ◽

Vol 2 (10) ◽

pp. 2625-2629 ◽

Cited By ~ 143

Author(s):

H. M. Berschneider ◽

M. R. Knowles ◽

R. G. Azizkhan ◽

R. C. Boucher ◽

N. A. Tobey ◽

...

Keyword(s):

Cystic Fibrosis ◽

Chloride Transport

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Loci of intestinal distress in cystic fibrosis knockout mice

Physiological Genomics ◽

10.1152/physiolgenomics.00114.2002 ◽

2003 ◽

Vol 12 (2) ◽

pp. 79-84 ◽

Cited By ~ 15

Author(s):

Christina K. Haston ◽

Lap-Chee Tsui

Keyword(s):

Cystic Fibrosis ◽

X Chromosome ◽

Knockout Mice ◽

Mendelian Inheritance ◽

Genetic Dissection ◽

Male Mice ◽

Female Mice ◽

Genome Wide ◽

A Genome ◽

Strain Dependent

The strain-dependent survival of cystic fibrosis (CF) knockout mice has been used to map a modifier of CF, Cfm1, in mice and, subsequently, in humans. To identify additional modifiers of the CF phenotype, in this study, the survival of F2 CF mice derived from a cross between congenic C57BL/6J CF and BALB/cJ CF heterozygotes was followed up to 12 wk of age. A genome-wide linkage scan completed in F2 CF mice revealed a chromosome 10 locus ( P = 1.2 × 10−4) to predict for intestinal distress in CF male mice. An X chromosome locus for which non-Mendelian inheritance favoring B6 alleles in the surviving CF mice and BALB alleles in mice of a control population, was identified. The survival of female mice, both F2 CF and F2 control, was linked to loci on chromosomes 3 and 5. The identification of additional putative CF modifier loci may permit further genetic dissection of the complex CF phenotype.

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CFTR Deficiency Affects Glucose Homeostasis via Regulating GLUT4 Plasma Membrane Transportation

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.630654 ◽

2021 ◽

Vol 9 ◽

Author(s):

Junzhong Gu ◽

Weiwei Zhang ◽

Lida Wu ◽

Yuchun Gu

Keyword(s):

Cystic Fibrosis ◽

Glucose Homeostasis ◽

Knockout Mice ◽

Glucose Transporter ◽

Autosomal Recessive Disorder ◽

Cellular Level ◽

Transmembrane Conductance Regulator ◽

Glut4 Translocation ◽

Altered Glucose ◽

Insulin Responses

Cystic Fibrosis (CF) is an autosomal recessive disorder caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. CF-related diabetes (CFRD) is one of the most prevalent comorbidities of CF. Altered glucose homeostasis has been reported in CF patients. The mechanism has not been fully elucidated. Besides the consequence of pancreatic endocrine dysfunction, we focus on insulin-responsive tissues and glucose transportation to explain glucose homeostasis alteration in CFRD. Herein, we found that CFTR knockout mice exhibited insulin resistance and glucose tolerance. Furthermore, we demonstrated insulin-induced glucose transporter 4 (GLUT4) translocation to the cell membrane was abnormal in the CFTR knockout mice muscle fibers, suggesting that defective intracellular GLUT4 transportation may be the cause of impaired insulin responses and glucose homeostasis. We further demonstrated that PI(4,5)P2 could rescue CFTR related defective intracellular GLUT4 transportation, and CFTR could regulate PI(4,5)P2 cellular level through PIP5KA, suggesting PI(4,5)P2 is a down-stream signal of CFTR. Our results revealed a new signal mechanism of CFTR in GLUT4 translocation regulation, which helps explain glucose homeostasis alteration in CF patients.

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In vivo activation of CFTR-dependent chloride transport in murine airway epithelium by CNP

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1997.273.5.l1065 ◽

1997 ◽

Vol 273 (5) ◽

pp. L1065-L1072 ◽

Cited By ~ 4

Author(s):

Thomas J. Kelley ◽

Calvin U. Cotton ◽

Mitchell L. Drumm

Keyword(s):

Cystic Fibrosis ◽

Chloride Transport ◽

Nasal Epithelium ◽

Transmembrane Conductance Regulator ◽

Wild Type ◽

Transmembrane Conductance ◽

Cyclic Monophosphate ◽

Δf508 Cftr ◽

Membrane Bound

Inhibitors of guanosine 3′,5′-cyclic monophosphate (cGMP)-inhibited phosphodiesterases stimulate Cl− transport across the nasal epithelia of cystic fibrosis mice carrying the ΔF508 mutation [cystic fibrosis transmembrane conductance regulator (CFTR) (ΔF/ΔF)], suggesting a role for cGMP in regulation of epithelial ion transport. Here we show that activation of membrane-bound guanylate cyclases by C-type natriuretic peptide (CNP) stimulates hyperpolarization of nasal epithelium in both wild-type and ΔF508 CFTR mice in vivo but not in nasal epithelium of mice lacking CFTR [CFTR(−/−)]. With the use of a nasal transepithelial potential difference (TEPD) assay, CNP was found to hyperpolarize lumen negative TEPD by 6.1 ± 0.6 mV in mice carrying wild-type CFTR. This value is consistent with that obtained with 8-bromoguanosine 3′,5′-cyclic monophosphate (6.2 ± 0.9 mV). A combination of the adenylate cyclase agonist forskolin and CNP demonstrated a synergistic ability to induce Cl− secretion across the nasal epithelium of CFTR(ΔF/ΔF) mice. No effect on TEPD was seen with this combination when used on CFTR(−/−) mice, implying that the CNP-induced change in TEPD in CFTR(ΔF/ΔF) mice is CFTR dependent.

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ClC-5: ontogeny of an alternative chloride channel in respiratory epithelia

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00207.2001 ◽

2002 ◽

Vol 282 (3) ◽

pp. L501-L507 ◽

Cited By ~ 10

Author(s):

Rebecca D. Edmonds ◽

Ian V. Silva ◽

William B. Guggino ◽

Robert B. Butler ◽

Pamela L. Zeitlin ◽

...

Keyword(s):

Cystic Fibrosis ◽

Lung Disease ◽

Chloride Channel ◽

Chloride Channels ◽

Chloride Transport ◽

Premature Death ◽

Fetal Lung ◽

Chloride Secretion ◽

Normal Lung ◽

Ribonuclease Protection Assay

Chloride transport is critical to many functions of the lung. Molecular defects in the best-known chloride channel, cystic fibrosis transmembrane conductance regulator (CFTR), lead to impaired function of airway defensins, hydration of airway surface fluid, and mucociliary clearance leading to chronic lung disease, and premature death, but do not cause defects in lung development. We examined the expression of one member of the ClC family of volume- and voltage-regulated channels using the ribonuclease protection assay and Western blot analysis in rats. ClC-5 mRNA and protein are most strongly expressed in the fetal lung, and expression is maintained although downregulated postnatally. In addition, using immunocytochemistry, we find that ClC-5 is predominantly expressed along the luminal surface of the airway epithelium, suggesting that ClC-5 may participate in lung chloride secretion. Identifying candidate genes for critical ion transport functions is essential for understanding normal lung morphogenesis and the pathophysiology of several lung diseases. In addition, the manipulation of non-CFTR chloride channels may provide a viable approach for treating cystic fibrosis lung disease.

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Examining basal chloride transport using the nasal potential difference response in a murine model

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.2001.281.5.l1173 ◽

2001 ◽

Vol 281 (5) ◽

pp. L1173-L1179 ◽

Cited By ~ 11

Author(s):

Kristine G. Brady ◽

Thomas J. Kelley ◽

Mitchell L. Drumm

Keyword(s):

Cystic Fibrosis ◽

Chloride Transport ◽

Inbred Mice ◽

Inbred Strains ◽

Potential Difference ◽

Transmembrane Conductance Regulator ◽

Transmembrane Conductance ◽

Inbred Strains Of Mice ◽

Cystic Fibrosis Transmembrane

Epithelia of humans and mice with cystic fibrosis are unable to secrete chloride in response to a chloride gradient or to cAMP-elevating agents. Bioelectrical properties measured using the nasal transepithelial potential difference (TEPD) assay are believed to reflect these cystic fibrosis transmembrane conductance regulator (CFTR)-dependent chloride transport defects. Although the response to forskolin is CFTR mediated, the mechanisms responsible for the response to a chloride gradient are unknown. TEPD measurements performed on inbred mice were used to compare the responses to low chloride and forskolin in vivo. Both responses show little correlation between or within inbred strains of mice, suggesting they are mediated through partially distinct mechanisms. In addition, these responses were assayed in the presence of several chloride channel inhibitors, including DIDS, diphenylamine-2-carboxylate, glibenclamide, and 5-nitro-2-(3-phenylpropylamino)-benzoic acid, and a protein kinase A inhibitor, the Rp diastereomer of adenosine 3′,5′-cyclic monophosphothioate ( Rp-cAMPS). The responses to low chloride and forskolin demonstrate significantly different pharmacological profiles to both DIDS and Rp-cAMPS, indicating that channels in addition to CFTR contribute to the low chloride response.

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