Comparison of cystic fibrosis transmembrane conductance regulator (CFTR) and ciliary beat frequency activation by the CFTR Modulators Genistein, VRT-532, and UCCF-152 in primary sinonasal epithelial cultures.
OBJECTIVE
Pharmacologic activation of mucociliary clearance (MCC) represents an emerging therapeutic strategy for patients with chronic rhinosinusitis, even in the absence of congenital mutations of the CFTR gene. Drug discovery efforts have identified small molecules that activate the cystic fibrosis transmembrane conductance regulator (CFTR), including potentiators under development for treatment of cystic fibrosis.


OBJECTIVE
To evaluate the properties of CFTR modulators and their effects on ciliary beat frequency (CBF) in human sinonasal epithelium (HSNE).


METHODS
Primary HSNE cultures (wild type and F508del/F508del) were used to compare stimulation of CFTR-mediated Cl- conductance and CBF by the CFTR modulators genistein, VRT-532, and UCCF-152.


METHODS
Increase in CFTR-dependent anion transport and CBF.


RESULTS
HSNE cultures were analyzed using pharmacologic manipulation of ion transport (change in short-circuit current [∆ISC]) and high-speed digital imaging (CBF). Activation of CFTR-dependent anion transport was significantly different among agonists (P < .001), with genistein exerting the greatest effect (mean [SD] ∆ISC, genistein, 23.1 [1.8] μA/cm2² > VRT-532, 8.1 [1.0] μA/cm² > UCCF-152, 3.4 [1.4] μA/cm² > control, 0.7 [0.2] μA/cm²; Tukey-Kramer P < .05) in the absence of forskolin. Genistein and UCCF-152 augmented CBF (under submerged conditions) significantly better (Tukey-Kramer P < .05) than cells treated with VRT-532 or dimethyl sulfoxide vehicle control (mean [SD] fold change over baseline, genistein, 1.63 [0.06]; UCCF-152, 1.56 [0.06]; VRT-532, 1.38 [0.08]; control, 1.27 [0.02]). Activation of CBF was blunted in F508del/F508del HSNE cultures.


CONCLUSIONS
The degree of CBF stimulation was not dependent on the magnitude of Cl- secretion, suggesting that different mechanisms of action may underlie MCC activation by these small molecule potentiators. Agents that activate both CFTR-dependent ISC and CBF are particularly attractive as therapeutics because they may address 2 independent pathways that contribute to deficient MCC in chronic rhinosinusitis.
Division of Otolaryngology, Department of Surgery, University of Alabama at Birmingham.
Bryant T
BT
Conger
Shaoyan
S
Zhang
Daniel
D
Skinner
Stephen B
SB
Hicks
Eric J
EJ
Sorscher
Steven M
SM
Rowe
Bradford A
BA
Woodworth
D002478:Cells, Cultured; D003408:Cresols / Q000494:pharmacology*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D004594:Electrophysiology; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D019833:Genistein / Q000494:pharmacology*; D006801:Humans; D017136:Ion Transport / Q000187:drug effects; D007555:Isoxazoles / Q000494:pharmacology*; D009079:Mucociliary Clearance / Q000187:drug effects* / Q000235:genetics; D009297:Nasal Mucosa / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011720:Pyrazoles / Q000494:pharmacology*; D012220:Rhinitis / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology; D012680:Sensitivity and Specificity; D012852:Sinusitis / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology
C584469:3-(2-benzyloxyphenyl)-5-chloromethylisoxazole; D003408:Cresols; D007555:Isoxazoles; D011720:Pyrazoles; C535089:VRT 532; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D019833:Genistein