Monoamine oxidase inhibition improves vascular function in mammary arteries from nondiabetic and diabetic patients with coronary heart disease.
Monoamine oxidases (MAOs) are mitochondrial enzymes with 2 isoforms that have emerged as important contributors to cardiovascular oxidative stress via the constant generation of hydrogen peroxide. The present study was purported to assess whether MAO-derived H2O2contributes to the endothelial dysfunction in mammary arteries harvested from coronary heart disease patients with and without diabetes mellitus subjected to coronary artery bypass grafting. To this aim, the effects of MAO inhibition on vascular contractility to phenylephrine and endothelial-dependent relaxation (EDR) in response to acetylcholine were studied in vascular segments. Clorgyline (irreversible MAO-A inhibitor), selegiline (irreversible MAO-B inhibitor), and moclobemide (reversible MAO-A inhibitor) were applied in the organ bath (10 μmol/L). MAO expression was assessed by immunohistochemistry. We found a constant impairment of EDR that has been significantly attenuated in the presence of the MAO-A and MAO-B inhibitors in both groups of coronary heart disease patients. MAO-B was the dominant isoform in all human diseased vessels. In conclusion, in vitro inhibition of MAO significantly improved EDR in human mammary arteries, regardless of the presence of diabetes. These data suggest that MAO inhibitors might be useful in restoring endothelial response in clinical conditions associated with increased oxidative stress, such as coronary artery disease and diabetes.
a Department of Parasitology, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Rodica
R
Lighezan
b Department of Pathophysiology, "Victor Babeş" University of Medicine and Pharmacy, 2, Eftimie Murgu Sq., 300041 Timişoara, Romania.|j Center for Translational Research and Systems Medicine, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Adrian
A
Sturza
b Department of Pathophysiology, "Victor Babeş" University of Medicine and Pharmacy, 2, Eftimie Murgu Sq., 300041 Timişoara, Romania.|j Center for Translational Research and Systems Medicine, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Oana M
OM
Duicu
c Department of Histology, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Raluca A
RA
Ceausu
d Department of Morphopathology, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Adrian
A
Vaduva
e Department of Cardiovascular Surgery, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Marian
M
Gaspar
e Department of Cardiovascular Surgery, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Horea
H
Feier
f Department of Anatomy, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Monica
M
Vaida
g Department of Cardiology - 2nd Cardiology Clinic, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Viviana
V
Ivan
h Department of Internal Medicine I, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.|j Center for Translational Research and Systems Medicine, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Daniel
D
Lighezan
b Department of Pathophysiology, "Victor Babeş" University of Medicine and Pharmacy, 2, Eftimie Murgu Sq., 300041 Timişoara, Romania.|j Center for Translational Research and Systems Medicine, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Danina M
DM
Muntean
i Department of Cardiology - 1st Cardiology Clinic, "Victor Babeş" University of Medicine and Pharmacy, Timişoara, Romania.
Cristian
C
Mornos
MAO inhibitors; coronaropathie; coronary artery disease; diabetes mellitus; diabète sucré; dysfonction endothéliale; endothelial dysfunction; inhibiteurs des MAO; monoamine oxidases; monoamines-oxydases