First evidence for a crosstalk between mitochondrial and NADPH oxidase-derived reactive oxygen species in nitroglycerin-triggered vascular dysfunction.
Chronic nitroglycerin treatment results in development of nitrate tolerance associated with endothelial dysfunction (ED). We sought to clarify how mitochondria- and NADPH oxidase (Nox)-derived reactive oxygen species (ROS) contribute to nitrate tolerance and nitroglycerin-induced ED. Nitrate tolerance was induced by nitroglycerin infusion in male Wistar rats (100 microg/h/4 day) and in C57/Bl6, p47(phox/) and gp91(phox/) mice (50 microg/h/4 day). Protein and mRNA expression of Nox subunits were unaltered by chronic nitroglycerin treatment. Oxidative stress was determined in vascular rings and mitochondrial fractions of nitroglycerin-treated animals by L-012 enhanced chemiluminescence, revealing a dominant role of mitochondria for nitrate tolerance development. Isometric tension studies revealed that genetic deletion or inhibition (apocynin, 0.35 mg/h/4 day) of Nox improved ED, whereas nitrate tolerance was unaltered. Vice versa, nitrate tolerance was attenuated by co-treatment with the respiratory chain complex I inhibitor rotenone (100 microg/h/4 day) or the mitochondrial permeability transition pore blocker cyclosporine A (50 microg/h/4 day). Both compounds improved ED, suggesting a link between mitochondrial and Nox-derived ROS. Mitochondrial respiratory chain-derived ROS are critical for the development of nitrate tolerance, whereas Nox-derived ROS mediate nitrate tolerance-associated ED. This suggests a crosstalk between mitochondrial and Nox-derived ROS with distinct mechanistic effects and sites for pharmacological intervention.
2nd Medical Clinic, Department of Cardiology, Johannes Gutenberg University, Mainz, Germany.
Philip
P
Wenzel
Hanke
H
Mollnau
Matthias
M
Oelze
Eberhard
E
Schulz
Jennifer M Dias
JM
Wickramanayake
Johanna
J
Müller
Swenja
S
Schuhmacher
Marcus
M
Hortmann
Stephan
S
Baldus
Tommaso
T
Gori
Ralf P
RP
Brandes
Thomas
T
Münzel
Andreas
A
Daiber
D000818:Animals; D001011:Aorta / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D015153:Blotting, Western; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D016572:Cyclosporine / Q000008:administration & dosage / Q000494:pharmacology; D004996:Ethidium / Q000031:analogs & derivatives / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008929:Mitochondria, Heart / Q000187:drug effects / Q000378:metabolism; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism*; D005996:Nitroglycerin / Q000008:administration & dosage / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D026361:Reactive Nitrogen Species / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012402:Rotenone / Q000008:administration & dosage / Q000494:pharmacology; D014162:Transfection; D014661:Vasoconstriction / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology
C506392:2-hydroxyethidium; D012333:RNA, Messenger; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species; D014665:Vasodilator Agents; D012402:Rotenone; D016572:Cyclosporine; D019255:NADPH Oxidases; D004996:Ethidium; D005996:Nitroglycerin