Soluble CD36 in plasma is increased in patients with symptomatic atherosclerotic carotid plaques and is related to plaque instability.
OBJECTIVE
The risk for cardiovascular events is related to the composition and stability of an atherosclerotic plaque driven by inflammation and deposition of lipids. Scavenger receptors are a family of cell surface receptors involved in lipid uptake and inflammation. Recently, we found that soluble CD36 is increased in plasma from patients with diabetes strongly correlated with insulin resistance.


METHODS
We tested whether soluble CD36 is a marker of plaque stability in patients with high-grade internal carotid stenoses (n=62). The patients were classified according to plaque symptomatology and plaque echogenicity on ultrasound examination.


RESULTS
When patients were divided into 3 groups according to the latest clinical symptoms from plaques (ie, symptoms within the last 2 months [n=16], symptoms within the last 2 to 6 months [n=15], or asymptomatic [n=31]), the former group had significantly raised plasma levels of soluble CD36 as compared with the other 2 groups. In contrast, we found no differences in plasma levels of C-reactive protein, beta-thromboglobulin, lipid parameters, or HbA1C between these groups. The patients with echolucent carotid plaques (n=20) tended to have higher soluble CD36 levels in plasma compared with those with echogenic/heterogenic plaque (n=39; P=0.087). By immunohistochemistry, CD36 was localized to macrophages-rich area of intima within the atherosclerotic lesion.


CONCLUSIONS
We propose that sCD36 may be a marker of plaque instability and symptomatic carotid atherosclerosis, possibly at least partly as a result of CD36 release to the circulation from the foam cells within the atherosclerotic lesion.
Handberg
Aase
A
Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark.
Skjelland
Mona
M
Michelsen
Annika E
AE
Sagen
Ellen Lund
EL
Krohg-Sørensen
Kirsten
K
Russell
David
D
Dahl
Arve
A
Ueland
Thor
T
Oie
Erik
E
Aukrust
Pål
P
Halvorsen
Bente
B
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D018955:CD36 Antigens / Q000097:blood*; D002340:Carotid Artery Diseases / Q000097:blood / Q000473:pathology; D016893:Carotid Stenosis / Q000097:blood / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged
D015415:Biomarkers; D018955:CD36 Antigens