1. The effect of NO-donors on chloride efflux, intracellular Ca2+ concentration and mRNA expression of CFTR and ENaC in cystic fibrosis airway epithelial cells
- Author
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Rashida Hussain, Marie Johannesson, Igor Oliynyk, Godfried M. Roomans, and Ahmad Amin
- Subjects
Epithelial sodium channel ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,Cystic Fibrosis ,Clinical Biochemistry ,Cystic Fibrosis Transmembrane Conductance Regulator ,chemistry.chemical_element ,Bronchi ,Endogeny ,Calcium ,Cystic fibrosis ,Cell Line ,Pathology and Forensic Medicine ,Chlorides ,Internal medicine ,medicine ,Nitric Oxide Donors ,RNA, Messenger ,Epithelial Sodium Channels ,Molecular Biology ,business.industry ,Epithelial Cells ,Triazoles ,respiratory system ,medicine.disease ,Molecular biology ,digestive system diseases ,respiratory tract diseases ,Endocrinology ,Gene Expression Regulation ,chemistry ,Cell culture ,Respiratory epithelium ,Efflux ,business ,Intracellular - Abstract
Since previous studies showed that the endogenous bronchodilator, S-nitrosglutathione (GSNO), caused a marked increase in CFTR-mediated chloride (Cl(-)) efflux and improved the trafficking of CFTR to the plasma membrane, and that also the nitric oxide (NO)-donor GEA3162 had a similar, but smaller, effect on Cl(-) efflux, it was investigated whether the NO-donor properties of GSNO were relevant for its effect on Cl(-) efflux from airway epithelial cells. Hence, the effect of a number of other NO-donors, sodium nitroprusside (SNP), S-nitroso-N-acetyl-DL-penicillamine (SNAP), diethylenetriamine/nitric oxide adduct (DETA-NO), and diethylenetriamine/nitric oxide adduct (DEA-NONOate) on Cl(-) efflux from CFBE (∆F508/∆F508-CFTR) airway epithelial cells was tested. Cl(-) efflux was determined using the fluorescent N-(ethoxycarbonylmethyl)-6-methoxyquinoliniu bromide (MQAE)-technique. Possible changes in the intracellular Ca(2+) concentration were tested by the fluorescent fluo-4 method in a confocal microscope system. Like previously with GSNO, after 4 h incubation with the NO-donor, an increased Cl(-) efflux was found (in the order SNAPDETA-NOSNP). The effect of DEA-NONOate on Cl(-) efflux was not significant, and the compound may have (unspecific) deleterious effects on the cells. Again, as with GSNO, after a short (5 min) incubation, SNP had no significant effect on Cl(-) efflux. None of the NO-donors that had a significant effect on Cl(-) efflux caused significant changes in the intracellular Ca(2+) concentration. After 4 h preincubation, SNP caused a significant increase in the mRNA expression of CFTR. SNAP and DEA-NONOate decreased the mRNA expression of all ENaC subunits significantly. DETA-NO caused a significant decrease only in α-ENaC expression. After a short preincubation, none of the NO-donors had a significant effect, neither on the expression of CFTR, nor on that of the ENaC subunits in the presence and absence of L-cysteine. It can be concluded that the effect of GSNO on Cl(-) efflux is, at least in part, due to its properties as an NO-donor, and the effect is likely to be mediated by CFTR, not by Ca(2+)-activated Cl(-) channels.
- Published
- 2013
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