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Imaging brain deoxyglucose uptake and metabolism by glucoCEST MRI.

ABSTRACT: 2-Deoxy-D-glucose (2DG) is a known surrogate molecule that is useful for inferring glucose uptake and metabolism. Although (13)C-labeled 2DG can be detected by nuclear magnetic resonance (NMR), its low sensitivity for detection prohibits imaging to be performed. Using chemical exchange saturation transfer (CEST) as a signal-amplification mechanism, 2DG and the phosphorylated 2DG-6-phosphate (2DG6P) can be indirectly detected in (1)H magnetic resonance imaging (MRI). We showed that the CEST signal changed with 2DG concentration, and was reduced by suppressing cerebral metabolism with increased general anesthetic. The signal changes were not affected by cerebral or plasma pH, and were not correlated with altered cerebral blood flow as demonstrated by hypercapnia; neither were they related to the extracellular glucose amounts as compared with injection of D- and L-glucose. In vivo (31)P NMR revealed similar changes in 2DG6P concentration, suggesting that the CEST signal reflected the rate of glucose assimilation. This method provides a new way to use widely available MRI techniques to image deoxyglucose/glucose uptake and metabolism in vivo without the need for isotopic labeling of the molecules.

SUBMITTER: Nasrallah FA

PROVIDER: S-EPMC3734779 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Imaging brain deoxyglucose uptake and metabolism by glucoCEST MRI.

Nasrallah Fatima A FA Pagès Guilhem G Kuchel Philip W PW Golay Xavier X Chuang Kai-Hsiang KH

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20130515 8

2-Deoxy-D-glucose (2DG) is a known surrogate molecule that is useful for inferring glucose uptake and metabolism. Although (13)C-labeled 2DG can be detected by nuclear magnetic resonance (NMR), its low sensitivity for detection prohibits imaging to be performed. Using chemical exchange saturation transfer (CEST) as a signal-amplification mechanism, 2DG and the phosphorylated 2DG-6-phosphate (2DG6P) can be indirectly detected in (1)H magnetic resonance imaging (MRI). We showed that the CEST signa ...[more]

PMID: 23673434

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Dataset Information

Imaging brain deoxyglucose uptake and metabolism by glucoCEST MRI.

Publications

Imaging brain deoxyglucose uptake and metabolism by glucoCEST MRI.

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