Hongyu Li1, Iain A Findlay, David N Sheppard. 1. Department of Physiology, University of Bristol, School of Medical Sciences, University Walk, Bristol, United Kingdom.
Abstract
BACKGROUND: In autosomal-dominant polycystic kidney disease (ADPKD), cAMP-stimulated cell proliferation and Cl- secretion via the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel drive the enlargement of fluid-filled epithelial cysts. To investigate how CFTR blockers inhibit cyst growth, we studied cAMP-dependent Cl- secretion, cell proliferation, and cyst growth using type I Madin Darby canine kidney (MDCK) cells as a model of renal cyst development and growth. METHODS: We grew MDCK cysts in collagen gels in the presence of the cAMP agonist forskolin, measured Cl- secretion with the Ussing chamber technique, and assayed cell proliferation using nonpolarized and polarized MDCK cells. To inhibit CFTR, we used glibenclamide, 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), genistein, and the specific CFTR inhibitor CFTRinh-172. As controls, we tested the effects of blockers of other types of apical membrane Cl- channels and inhibitors of basolateral membrane ion channels and transporters. RESULTS: In the absence of inhibitors of transepithelial ion transport, forskolin stimulated dramatic cyst growth. CFTR blockers and inhibitors of basolateral membrane ion channels and transporters retarded cyst growth. In contrast, blockers of other types of apical membrane Cl- channels, which were without effect on CFTR, failed to inhibit cyst growth. Inhibition of cyst growth by CFTR blockers was correlated with inhibition of cAMP-stimulated Cl- current (correlation coefficient = 0.81; P < 0.05), but not cell proliferation (correlation coefficient = 0.50; P > 0.05). CONCLUSION: Our data suggest that CFTR blockers might retard cyst growth predominantly by inhibiting fluid accumulation within the cyst lumen.
BACKGROUND: In autosomal-dominant polycystic kidney disease (ADPKD), cAMP-stimulated cell proliferation and Cl- secretion via the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel drive the enlargement of fluid-filled epithelial cysts. To investigate how CFTR blockers inhibit cyst growth, we studied cAMP-dependent Cl- secretion, cell proliferation, and cyst growth using type I Madin Darby canine kidney (MDCK) cells as a model of renal cyst development and growth. METHODS: We grew MDCK cysts in collagen gels in the presence of the cAMP agonist forskolin, measured Cl- secretion with the Ussing chamber technique, and assayed cell proliferation using nonpolarized and polarized MDCK cells. To inhibit CFTR, we used glibenclamide, 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), genistein, and the specific CFTR inhibitor CFTRinh-172. As controls, we tested the effects of blockers of other types of apical membrane Cl- channels and inhibitors of basolateral membrane ion channels and transporters. RESULTS: In the absence of inhibitors of transepithelial ion transport, forskolin stimulated dramatic cyst growth. CFTR blockers and inhibitors of basolateral membrane ion channels and transporters retarded cyst growth. In contrast, blockers of other types of apical membrane Cl- channels, which were without effect on CFTR, failed to inhibit cyst growth. Inhibition of cyst growth by CFTR blockers was correlated with inhibition of cAMP-stimulated Cl- current (correlation coefficient = 0.81; P < 0.05), but not cell proliferation (correlation coefficient = 0.50; P > 0.05). CONCLUSION: Our data suggest that CFTR blockers might retard cyst growth predominantly by inhibiting fluid accumulation within the cyst lumen.
Authors: Hongyu Li; Hennie Valkenier; Luke W Judd; Peter R Brotherhood; Sabir Hussain; James A Cooper; Ondřej Jurček; Hazel A Sparkes; David N Sheppard; Anthony P Davis Journal: Nat Chem Date: 2015-11-02 Impact factor: 24.427
Authors: Vani Narayanan; Laurel E Schappell; Carl R Mayer; Ashley A Duke; Travis J Armiger; Paul T Arsenovic; Abhinav Mohan; Kris N Dahl; Jason P Gleghorn; Daniel E Conway Journal: Curr Biol Date: 2020-01-23 Impact factor: 10.834
Authors: C Norez; C Vandebrouck; J Bertrand; S Noel; E Durieu; N Oumata; H Galons; F Antigny; A Chatelier; P Bois; L Meijer; F Becq Journal: Br J Pharmacol Date: 2014-11 Impact factor: 8.739