TY - JOUR
T1 - NF-κB activation is required for apoptosis in fibrocystin/polyductin- depleted kidney epithelial cells
AU - Mangolini, Alessandra
AU - Bogo, Marco
AU - Durante, Chiara
AU - Borgatti, Monica
AU - Gambari, Roberto
AU - Harris, Peter C.
AU - Rizzuto, Rosario
AU - Pinton, Paolo
AU - Aguiari, Gianluca
AU - Del Senno, Laura
N1 - Funding Information:
Acknowledgments We thank Dr. Johannes A. Schmid (Medical University, Vienna, Austria) for providing NFkB-GFP plasmid, Anna Forster for correcting the manuscript and I. Maestri and A. Canella for technical assistance. This work was supported by Cassa di Risparmio di Ferrara, Cassa di Risparmio di Cento, Italian MIUR COFIN 2008 and Regione Emilia Romagna (Ricerca Regione-Università) 2007–2009.
PY - 2010/1
Y1 - 2010/1
N2 - Autosomal recessive polycystic kidney disease (ARPKD) is caused by mutations in PKHD1, a gene encoding fibrocystin/polyductin (FC1), a membrane-associated receptor-like protein involved in the regulation of tubular cell adhesion, proliferation and apoptosis. Although it is generally accepted that apoptosis is implicated in ARPKD, the question of whether increased apoptosis is a normal response to abnormal cell proliferation or, instead, it is a primary event, is still subject to debate. In support of the latter hypothesis, we hereby provide evidence that apoptosis occurs in the absence of hyper-proliferation of FC1-depleted kidney cells. In fact, a decrease in cell proliferation, with a concomitant increase in apoptotic index and caspase-3 activity was observed in response to FC1-depletion by PKHD1 siRNA silencing in HEK293 and 4/5 tubular cells. FC1-depletion also induced reduction in ERK1/2 kinase activation, upregulation of the pro-apoptotic protein p53 and activation of NF-κB, a transcription factor which reduces apoptosis in many organs and tissues. Interestingly, selective inactivation of NF-κB using either an NF-κB decoy or parthenolide, a blocker of IKK-dependent NF-κB activation, reduced, rather then increased, apoptosis and p53 levels in FC1-depleted cells. Therefore, the proapoptotic function of NF-κB during cell death by FC1-depletion in kidney cells is evident.
AB - Autosomal recessive polycystic kidney disease (ARPKD) is caused by mutations in PKHD1, a gene encoding fibrocystin/polyductin (FC1), a membrane-associated receptor-like protein involved in the regulation of tubular cell adhesion, proliferation and apoptosis. Although it is generally accepted that apoptosis is implicated in ARPKD, the question of whether increased apoptosis is a normal response to abnormal cell proliferation or, instead, it is a primary event, is still subject to debate. In support of the latter hypothesis, we hereby provide evidence that apoptosis occurs in the absence of hyper-proliferation of FC1-depleted kidney cells. In fact, a decrease in cell proliferation, with a concomitant increase in apoptotic index and caspase-3 activity was observed in response to FC1-depletion by PKHD1 siRNA silencing in HEK293 and 4/5 tubular cells. FC1-depletion also induced reduction in ERK1/2 kinase activation, upregulation of the pro-apoptotic protein p53 and activation of NF-κB, a transcription factor which reduces apoptosis in many organs and tissues. Interestingly, selective inactivation of NF-κB using either an NF-κB decoy or parthenolide, a blocker of IKK-dependent NF-κB activation, reduced, rather then increased, apoptosis and p53 levels in FC1-depleted cells. Therefore, the proapoptotic function of NF-κB during cell death by FC1-depletion in kidney cells is evident.
KW - Apoptosis
KW - Autosomal recessive polycystic kidney disease (ARPKD)
KW - Fibrocystin
KW - Kidney cells
KW - NF-κB inhibitors
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U2 - 10.1007/s10495-009-0426-7
DO - 10.1007/s10495-009-0426-7
M3 - Article
C2 - 19943112
AN - SCOPUS:77949261505
SN - 1360-8185
VL - 15
SP - 94
EP - 104
JO - Apoptosis
JF - Apoptosis
IS - 1
ER -