Referenced in: none

Automatically associated channels: TRP , TRPC , TRPC6

Title: Effect of VX-770 (ivacaftor) and OAG on Ca2+ influx and CFTR activity in G551D and F508del-CFTR expressing cells.

Authors: Laura Vachel, Caroline Norez, Frédéric Becq, Clarisse Vandebrouck

Journal, date & volume: J. Cyst. Fibros., 2013 Dec , 12, 584-91

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/23757361

Abstract
TRPC6 has been proposed to be responsible for the abnormal OAG-dependent Ca(2+) influx in cystic fibrosis (CF) cells and we hypothesized that it interacts with CFTR. Here, we investigated how this functional complex operates in CF and non-CF epithelial cells.Chinese hamster ovary (CHO) cells stably transfected with pNut vector containing wild type CFTR (CHO-WT), F508del-CFTR (CHO-F508del) or G551D-CFTR(CHO-G551D) were used. Calcium channel activity was recorded using Fluo-4 probe and CFTR activity was measured by iodide efflux technique in the presence of CFTR activators (forskolin, genistein) and VX-770, CFTR inhibitor (GPinh5a) and TRPC non-selective modulators (OAG, SKF96365).CFTR down regulates OAG Ca(2+) response and OAG Ca(2+) influx increases CFTR chloride efflux. Furthermore, we observed potentiation of G551D-CFTR activity when combining VX-770 and OAG.Taking advantage of the functional coupling between OAG-dependent Ca(2+) influx and CFTR, a combination of OAG and VX-770 could be a therapeutic strategy for homozygote patients bearing the G551D-CFTR mutation.