Superoxide production and expression of nox family proteins in human atherosclerosis.
BACKGROUND
NAD(P)H oxidases are important sources of superoxide in the vasculature, the activity of which is associated with risk factors for human atherosclerosis. This study was designed to investigate the localization of superoxide production and the expression of the Nox family of NAD(P)H oxidase proteins (gp91phox, Nox1, and Nox4) in nonatherosclerotic and atherosclerotic human coronary arteries.


RESULTS
In coronary artery segments from explanted human hearts, we examined intracellular superoxide production with dihydroethidium. In nonatherosclerotic coronary arteries, superoxide was present homogenously throughout the intima, media, and adventitia. In atherosclerotic arteries, there was an additional intense area of superoxide in the plaque shoulder, which is rich in macrophages and alpha-actin-positive cells. p22phox colocalized with gp91phox mainly in macrophages, whereas Nox4 was found only in nonphagocytic vascular cells. Expression of gp91phox and p22phox mRNA was associated with the severity of atherosclerosis. gp91phox correlated with the plaque macrophage content, whereas Nox4 correlated with the content of alpha-actin-positive cells. Nox1 expression was low both in human coronary arteries and isolated vascular cells.


CONCLUSIONS
Several Nox proteins, including gp91phox and Nox4, may contribute to increased intracellular oxidative stress in human coronary atherosclerosis in a cell-specific manner and thus may be involved in the genesis and progression of human coronary atherosclerotic disease.
Sorescu
Dan
D
Department of Medicine, Emory University, Atlanta, Ga 30322, USA.
Weiss
Daiana
D
Lassègue
Bernard
B
Clempus
Roza E
RE
Szöcs
Katalin
K
Sorescu
George P
GP
Valppu
Liisa
L
Quinn
Mark T
MT
Lambeth
J David
JD
Vega
J David
JD
Taylor
W Robert
WR
Griendling
Kathy K
KK
D001161:Arteriosclerosis / Q000378:metabolism* / Q000473:pathology; D002478:Cells, Cultured; D003324:Coronary Artery Disease / Q000378:metabolism* / Q000473:pathology; D003331:Coronary Vessels / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005456:Fluorescent Dyes; D006333:Heart Failure / Q000378:metabolism; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000096:biosynthesis* / Q000235:genetics; D009252:NADPH Dehydrogenase / Q000235:genetics / Q000378:metabolism; D000074662:NADPH Oxidase 2; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D013481:Superoxides / Q000032:analysis / Q000378:metabolism*
D005456:Fluorescent Dyes; D007527:Isoenzymes; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D010750:Phosphoproteins; D012333:RNA, Messenger; D013481:Superoxides; D009247:NADH, NADPH Oxidoreductases; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases; C498910:NOX4 protein, human; C086986:CYBA protein, human; D009252:NADPH Dehydrogenase