S-EPMC4487365 - [18F]FDG Accumulation in Early Coronary Atherosclerotic Lesions in Pigs. - OmicsDI

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Dataset Information

[18F]FDG Accumulation in Early Coronary Atherosclerotic Lesions in Pigs.

ABSTRACT:

Objective

Inflammation is an important contributor to atherosclerosis progression. A glucose analogue 18F-fluorodeoxyglucose ([18F]FDG) has been used to detect atherosclerotic inflammation. However, it is not known to what extent [18F]FDG is taken up in different stages of atherosclerosis. We aimed to study the uptake of [18F]FDG to various stages of coronary plaques in a pig model.

Methods

First, diabetes was caused by streptozotocin injections (50 mg/kg for 3 days) in farm pigs (n = 10). After 6 months on high-fat diet, pigs underwent dual-gated cardiac PET/CT to measure [18F]FDG uptake in coronary arteries. Coronary segments (n = 33) were harvested for ex vivo measurement of radioactivity and autoradiography (ARG).

Results

Intimal thickening was observed in 16 segments and atheroma type plaques in 10 segments. Compared with the normal vessel wall, ARG showed 1.7±0.7 times higher [18F]FDG accumulation in the intimal thickening and 4.1±2.3 times higher in the atheromas (P = 0.004 and P = 0.003, respectively). Ex vivo mean vessel-to-blood ratio was higher in segments with atheroma than those without atherosclerosis (2.6±1.2 vs. 1.3±0.7, P = 0.04). In vivo PET imaging showed the highest target-to-background ratio (TBR) of 2.7. However, maximum TBR was not significantly different in segments without atherosclerosis (1.1±0.5) and either intimal thickening (1.2±0.4, P = 1.0) or atheroma (1.6±0.6, P = 0.4).

Conclusions

We found increased uptake of [18F]FDG in coronary atherosclerotic lesions in a pig model. However, uptake in these early stage lesions was not detectable with in vivo PET imaging. Further studies are needed to clarify whether visible [18F]FDG uptake in coronary arteries represents more advanced, highly inflamed plaques.

SUBMITTER: Tarkia M

PROVIDER: S-EPMC4487365 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

[18F]FDG Accumulation in Early Coronary Atherosclerotic Lesions in Pigs.

Tarkia Miikka M Saraste Antti A Stark Christoffer C Vähäsilta Tommi T Savunen Timo T Strandberg Marjatta M Saunavaara Virva V Tolvanen Tuula T Teuho Jarmo J Teräs Mika M Metsälä Olli O Rinne Petteri P Heinonen Ilkka I Savisto Nina N Pietilä Mikko M Saukko Pekka P Roivainen Anne A Knuuti Juhani J

PloS one 20150629 6

<h4>Objective</h4>Inflammation is an important contributor to atherosclerosis progression. A glucose analogue 18F-fluorodeoxyglucose ([18F]FDG) has been used to detect atherosclerotic inflammation. However, it is not known to what extent [18F]FDG is taken up in different stages of atherosclerosis. We aimed to study the uptake of [18F]FDG to various stages of coronary plaques in a pig model.<h4>Methods</h4>First, diabetes was caused by streptozotocin injections (50 mg/kg for 3 days) in farm pigs ...[more]

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