Dataset Information

Cross-sectional and Test-Retest Characterization of PET with [(18)F]FP-(+)-DTBZ for ? Cell Mass Estimates in Diabetes.

ABSTRACT:

Purpose

The vesicular monoamine transporter, type 2 (VMAT2) is expressed by insulin producing ? cells and was evaluated as a biomarker of ? cell mass (BCM) by positron emission tomography (PET) with [(18)F]fluoropropyl-dihydrotetrabenazine ([(18)F]FP-(+)-DTBZ).

Procedures

We evaluated the feasibility of longitudinal pancreatic PET VMAT2 quantification in the pancreas in two studies of healthy controls and patients with type 1 or 2 diabetes. VMAT2 binding potential (BPND) was estimated voxelwise using a reference tissue method in a cross-sectional study, followed by assessment of reproducibility using a test-retest paradigm. Metabolic function was evaluated by stimulated c-peptide measurements.

Results

Pancreatic BPND was significantly decreased in patients with type 1 diabetes relative to controls and the test-retest variability was 9.4%.

Conclusions

Pancreatic VMAT2 content is significantly reduced in long-term diabetes patients relative to controls and repeat scans are sufficiently reproducible to suggest the feasibility clinically VMAT2 measurements in longitudinal studies of new onset diabetes.

SUBMITTER: Freeby MJ

PROVIDER: S-EPMC4783444 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Publications

Cross-sectional and Test-Retest Characterization of PET with [(18)F]FP-(+)-DTBZ for β Cell Mass Estimates in Diabetes.

Freeby Matthew J MJ Kringas Patricia P Goland Robin S RS Leibel Rudolph L RL Maffei Antonella A Divgi Chaitan C Ichise Masanori M Harris Paul E PE

Molecular imaging and biology 20150914 2

<h4>Purpose</h4>The vesicular monoamine transporter, type 2 (VMAT2) is expressed by insulin producing β cells and was evaluated as a biomarker of β cell mass (BCM) by positron emission tomography (PET) with [(18)F]fluoropropyl-dihydrotetrabenazine ([(18)F]FP-(+)-DTBZ).<h4>Procedures</h4>We evaluated the feasibility of longitudinal pancreatic PET VMAT2 quantification in the pancreas in two studies of healthy controls and patients with type 1 or 2 diabetes. VMAT2 binding potential (BPND) was estim ...[more]

PMID: 26370678

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