TY - JOUR
T1 - Deficiency of polycystic kidney disease-1 gene (PKD1) expression increases A3 adenosine receptors in human renal cells
T2 - Implications for cAMP-dependent signalling and proliferation of PKD1-mutated cystic cells
AU - Aguiari, Gianluca
AU - Varani, Katia
AU - Bogo, Marco
AU - Mangolini, Alessandra
AU - Vincenzi, Fabrizio
AU - Durante, Chiara
AU - Gessi, Stefania
AU - Sacchetto, Valeria
AU - Catizone, Luigi
AU - Harris, Peter
AU - Rizzuto, Rosario
AU - Borea, Pier Andrea
AU - del Senno, Laura
N1 - Funding Information:
We thank Dr Johannes A. Schmid (Center of Biomolecular Medicine and Pharmacology, Medical University, Vienna, Austria) for providing NFkB-GFP plasmid; Anna Foster for correcting the manuscript and A. Canella for technical assistance. We also thank Prof. A. Faenza and Dr G. Feliciangeli (Transplant Center, and Nephrology Dialysis and Renal Transplantation Unit, S. Orsola University Hospital, Bologna, Italy) for ADPKD kidneys and Dr C. Daniele (S. Anna Hospital, Ferrara, Italy) for non ADPKD kidneys. MRE3008F20 and MRE 2029F20 were a kind gift from Prof. G. Baraldi (Ferrara University, Italy). This work was supported by Cassa di Risparmio di Ferrara, Cassa di Risparmio di Cento, Local University Funds, Telethon grant GGP05284.
PY - 2009/6
Y1 - 2009/6
N2 - Cyst growth and expansion in autosomal dominant polycystic kidney disease (ADPKD) has been attributed to numerous factors, including ATP, cAMP and adenosine signalling. Although the role of ATP and cAMP has been widely investigated in PKD1-deficient cells, no information is currently available on adenosine-mediated signalling. Here we investigate for the first time the impact of abnormalities of polycystin-1 (PC1) on the expression and functional activity of adenosine receptors, members of the G-protein-coupled receptor superfamily. Pharmacological, molecular and biochemical findings show that a siRNA-dependent PC1-depletion in HEK293 cells and a PKD1-nonsense mutation in cyst-derived cell lines result in increased expression of the A3 adenosine receptor via an NFkB-dependent mechanism. Interestingly, A3 adenosine receptor levels result higher in ADPKD than in normal renal tissues. Furthermore, the stimulation of this receptor subtype with the selective agonist Cl-IB-MECA causes a reduction in both cytosolic cAMP and cell proliferation in both PC1-deficient HEK293 cells and cystic cells. This reduction is associated with increased expression of p21waf and reduced activation not only of ERK1/2, but also of S6 kinase, the main target of mTOR signalling. In the light of these findings, the ability of Cl-IB-MECA to reduce disease progression in ADPKD should be further investigated. Moreover, our results suggest that NFkB, which is markedly activated in PC1-deficient and cystic cells, plays an important role in modulating A3AR expression in cystic cells.
AB - Cyst growth and expansion in autosomal dominant polycystic kidney disease (ADPKD) has been attributed to numerous factors, including ATP, cAMP and adenosine signalling. Although the role of ATP and cAMP has been widely investigated in PKD1-deficient cells, no information is currently available on adenosine-mediated signalling. Here we investigate for the first time the impact of abnormalities of polycystin-1 (PC1) on the expression and functional activity of adenosine receptors, members of the G-protein-coupled receptor superfamily. Pharmacological, molecular and biochemical findings show that a siRNA-dependent PC1-depletion in HEK293 cells and a PKD1-nonsense mutation in cyst-derived cell lines result in increased expression of the A3 adenosine receptor via an NFkB-dependent mechanism. Interestingly, A3 adenosine receptor levels result higher in ADPKD than in normal renal tissues. Furthermore, the stimulation of this receptor subtype with the selective agonist Cl-IB-MECA causes a reduction in both cytosolic cAMP and cell proliferation in both PC1-deficient HEK293 cells and cystic cells. This reduction is associated with increased expression of p21waf and reduced activation not only of ERK1/2, but also of S6 kinase, the main target of mTOR signalling. In the light of these findings, the ability of Cl-IB-MECA to reduce disease progression in ADPKD should be further investigated. Moreover, our results suggest that NFkB, which is markedly activated in PC1-deficient and cystic cells, plays an important role in modulating A3AR expression in cystic cells.
KW - ADPKD
KW - Adenosine receptor
KW - NFkB activation
KW - Polycystin-1
KW - Renal cell
KW - cAMP-dependent signalling
UR - http://www.scopus.com/inward/record.url?scp=67349163728&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=67349163728&partnerID=8YFLogxK
U2 - 10.1016/j.bbadis.2009.03.001
DO - 10.1016/j.bbadis.2009.03.001
M3 - Article
C2 - 19285554
AN - SCOPUS:67349163728
SN - 0925-4439
VL - 1792
SP - 531
EP - 540
JO - Biochimica et Biophysica Acta - Molecular Basis of Disease
JF - Biochimica et Biophysica Acta - Molecular Basis of Disease
IS - 6
ER -