Natriuretic peptides and nitric oxide induce endothelial apoptosis via a cGMP-dependent mechanism.
Apoptosis is a mode of cell death in which the cell participates in its own demise. We studied whether endothelium-derived relaxing factor, nitric oxide (NO), and natriuretic peptides affect apoptosis of rat vascular endothelial cells via a cGMP-dependent pathway and whether such effects are antagonized by an endothelium-derived vasoconstrictor, endothelin-1 (ET-1). Three natriuretic peptides (atrial natriuretic peptide, brain natriuretic peptide, and C-type natriuretic peptide) induced endothelial apoptosis as demonstrated by nucleosomal laddering on agarose gel electrophoresis and by the terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling method. This dose-dependent relation was assessed by quantifying the fragmented and intact DNA contents by the diphenylamine method. The atrial natriuretic peptide-induced endothelial apoptosis was completely blocked by a guanylate cyclase-coupled receptor antagonist (HS-142-1) and an inhibitor of cGMP-dependent protein kinase (KT5823). An NO donor, NOR3 ((+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexeneamide; FK409) also induced endothelial apoptosis; the effect of this compound was abrogated by KT5823 and an inhibitor of soluble guanylate cyclase, ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one). A cGMP derivative, 8-bromo-cGMP, but not the cAMP derivative 8-bromo-cAMP, caused endothelial apoptosis; the effect of ODQ was also abrogated by KT5823. Endothelial apoptosis induced by ANP, NOR3, and 8-bromo-cGMP was similarly antagonized by ET-1. ANP, NOR3, and 8-bromo-cGMP caused marked accumulations of the tumor suppressor gene product p53 but not of bcl-2, as determined by Western blot analysis. These results demonstrate for the first time that endothelium-derived NO and natriuretic peptides are proapoptotic factors for endothelial cells, whereas the endothelium-derived vasoconstrictor ET-1 is an antiapoptotic factor, suggesting that the countervailing balance between these vasodilators and vasoconstrictors, in addition to regulation of vascular tonus, may contribute to endothelial cell integrity.
Suenobu
N
N
Endocrine-Hypertension Division, Second Department of Internal Medicine, Tokyo Medical and Dental University, Pharmaceutical Research Laboratories, Pola R&D Laboratories, POLA Corp, Yokohama, Japan.
Shichiri
M
M
Iwashina
M
M
Marumo
F
F
Hirata
Y
Y
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D009320:Atrial Natriuretic Factor / Q000494:pharmacology; D006152:Cyclic GMP / Q000494:pharmacology*; D004247:DNA / Q000032:analysis; D053938:DNA Fragmentation; D019332:Endothelin-1 / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000166:cytology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006162:Guanylate Cyclase / Q000037:antagonists & inhibitors; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000494:pharmacology; D020098:Natriuretic Peptide, C-Type / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D010455:Peptides / Q000494:pharmacology*; D047428:Protein Kinase Inhibitors; D051381:Rats; D017208:Rats, Wistar; D014665:Vasodilator Agents / Q000494:pharmacology
D019332:Endothelin-1; D004791:Enzyme Inhibitors; D020030:Nitric Oxide Donors; D010455:Peptides; D047428:Protein Kinase Inhibitors; D014665:Vasodilator Agents; D020097:Natriuretic Peptide, Brain; D020098:Natriuretic Peptide, C-Type; D009569:Nitric Oxide; D009320:Atrial Natriuretic Factor; D004247:DNA; D006162:Guanylate Cyclase; D006152:Cyclic GMP