Protective effect of spironolactone on endothelial cell apoptosis.
Human umbilical vein endothelial cells (HUVECs) undergo apoptosis in response to serum deprivation. We show that the nonspecific mineralocorticoid receptor antagonist, spironolactone, protects from caspase-3 activation induced by serum deprivation in contrast to the selective mineralocorticoid receptor antagonist, eplerenone, that is nonprotective. We also demonstrate that progesterone, hydrocortisone, and dexamethasone all protect HUVECs from serum-deprivation-induced caspase-3 activation, whereas aldosterone and dihydrotestosterone have no effect. Spironolactone has been demonstrated to display agonist activity only to the progesterone receptor (PR), and we additionally show that spironolactone and progesterone, but not eplerenone, inhibit mitochondrial cytochrome c release and cleavage of nuclear poly (ADP-ribose) polymerase (PARP) and increase cell viability. Additionally, the PR antagonist mifepristone (RU486) partially blocked the inhibitory effect of both spironolactone and progesterone on caspase-3 activation, cytochrome c release, and nuclear PARP cleavage. Nitric oxide (NO) protects HUVECs from apoptosis in response to various stimuli including serum-deprivation; however, the NO synthase inhibitor N-monomethyl-l-arginine, did not abolish inhibition of caspase-3 activation or PARP cleavage by spironolactone. Thus, we demonstrate that spironolactone protects HUVECs from serum-deprivation-induced apoptosis by inhibition of caspase-3 activity, cytochrome c release and PARP cleavage by a NO-independent mechanism; further, this effect is likely mediated by the agonist properties of spironolactone toward the PR.
Department of Medicine and Experimental Oncology, Hypertension Unit, University of Torino, Italy. tracy.williams@libero.it
Tracy A
TA
Williams
Andrea
A
Verhovez
Alberto
A
Milan
Franco
F
Veglio
Paolo
P
Mulatero
D000450:Aldosterone / Q000494:pharmacology; D017209:Apoptosis; D015153:Blotting, Western; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D002470:Cell Survival; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D003907:Dexamethasone / Q000494:pharmacology; D013196:Dihydrotestosterone / Q000494:pharmacology; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D004789:Enzyme Activation; D000077545:Eplerenone; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D000451:Mineralocorticoid Receptor Antagonists / Q000494:pharmacology; D008928:Mitochondria / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D013148:Spironolactone / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D013997:Time Factors; D014471:Umbilical Veins / Q000166:cytology*
D000451:Mineralocorticoid Receptor Antagonists; D011980:Receptors, Progesterone; D013196:Dihydrotestosterone; D013148:Spironolactone; D009569:Nitric Oxide; D000450:Aldosterone; D000077545:Eplerenone; D003907:Dexamethasone; D045304:Cytochromes c; D019001:Nitric Oxide Synthase; D011065:Poly(ADP-ribose) Polymerases; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D006854:Hydrocortisone