Activation of the cystic fibrosis transmembrane conductance regulator by the flavonoid quercetin: Potential use as a biomarker of ΔF508 cystic fibrosis transmembrane conductance regulator rescue

Authors

Louise C. Pyle, The University of Alabama at Birmingham
Jennifer C. Fulton, The University of Alabama at Birmingham
Peter A. Sloane, The University of Alabama at Birmingham
Kyle Backer, The University of Alabama at Birmingham
Marina Mazur, The University of Alabama at Birmingham
Jeevan Prasain, The University of Alabama at Birmingham
Stephen Barnes, The University of Alabama at Birmingham
J. P. Clancy, The University of Alabama at Birmingham
Steven M. Rowe, The University of Alabama at Birmingham

Document Type

Journal Article

Publication Date

11-1-2010

Journal

American Journal of Respiratory Cell and Molecular Biology

Volume

43

DOI

10.1165/rcmb.2009-0281OC

Keywords

Airway epithelia; Cystic fibrosis; Nasal potential difference; Short-circuit current

Abstract

Therapies to correct the ΔF508 cystic fibrosis transmembrane conductance regulator (CFTR) folding defect require sensitive methods to detect channel activity in vivo. The β2 adrenergic receptor agonists, which provide the CFTR stimuli commonly used in nasal potential difference assays, may not overcome the channel gating defects seen in ΔF508 CFTR after plasma membrane localization. In this study, we identify an agent, quercetin, that enhances the detection of surface ΔF508 CFTR, and is suitable for nasal perfusion. A screen of flavonoids in CFBE41o- cells stably transduced with ΔF508 CFTR, corrected to the cell surface with low temperature growth, revealed that quercetin stimulated an increase in the short-circuit current. This increase was dose-dependent in both Fisher rat thyroid and CFBE41o- cells. High concentrations inhibited Cl - conductance. In CFBE41o- airway cells, quercetin (20 μg/ml) activated ΔF508 CFTR, whereas the β2 adrenergic receptor agonist isoproterenol did not. Quercetin had limited effects on cAMP levels, but did not produce detectable phosphorylation of the isolated CFTR R-domain, suggesting an activation independent of channel phosphorylation. When perfused in the nares of Cftr+ mice, quercetin (20 μg/ml) produced a hyperpolarization of the potential difference that was absent in Cftr -/- mice. Finally, quercetin-induced, dose-dependent hyperpolarization of the nasal potential difference was also seen in normal human subjects. Quercetin activates CFTR-mediated anion transport in respiratory epithelia in vitro and in vivo, and may be useful in studies intended to detect the rescue of ΔF508 CFTR by nasal potential difference.

APA Citation

Pyle, L., Fulton, J., Sloane, P., Backer, K., Mazur, M., Prasain, J., Barnes, S., Clancy, J., & Rowe, S. (2010). Activation of the cystic fibrosis transmembrane conductance regulator by the flavonoid quercetin: Potential use as a biomarker of ΔF508 cystic fibrosis transmembrane conductance regulator rescue. American Journal of Respiratory Cell and Molecular Biology, 43 (). http://dx.doi.org/10.1165/rcmb.2009-0281OC