Premium
Production of highly polarized [1‐ 13 C]acetate by rapid decarboxylation of [2‐ 13 C]pyruvate – application to hyperpolarized cardiac spectroscopy and imaging
Author(s) -
Steinhauser Jonas,
Wespi Patrick,
Kwiatkowski Grzegorz,
Kozerke Sebastian
Publication year - 2019
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.27782
Subject(s) - decarboxylation , chemistry , acetylcarnitine , nuclear magnetic resonance spectroscopy , in vivo , spectroscopy , metabolism , stereochemistry , biochemistry , catalysis , microbiology and biotechnology , biology , physics , quantum mechanics
Purpose The objective of the present work was to develop and implement an efficient approach to hyperpolarize [1‐ 13 C]acetate and apply it to in vivo cardiac spectroscopy and imaging. Methods Rapid hydrogen peroxide induced decarboxylation was used to convert hyperpolarized [2‐ 13 C]pyruvate into highly polarized [1‐ 13 C]acetate employing an additional step following rapid dissolution of [2‐ 13 C]pyruvate in a home‐built multi‐sample dissolution dynamic nuclear polarization system. Phantom dissolution experiments were conducted to determine optimal parameters of the decarboxylation reaction, retaining polarization and T 1 of [1‐ 13 C]acetate. In vivo feasibility of detecting [1‐ 13 C]acetate metabolism is demonstrated using slice‐selective spectroscopy and multi‐echo imaging of [1‐ 13 C]acetate and [1‐ 13 C]acetylcarnitine in the healthy rat heart. Results The first in vivo signal was observed ~23 s after dissolution. At the corresponding time point in the phantom experiments, 97.9 ± 0.4% of [2‐ 13 C]pyruvate were converted into [1‐ 13 C]acetate by the decarboxylation reaction. T 1 and polarization of [1‐ 13 C]acetate was determined to be 29.7 ± 1.9% and a 47.7 ± 0.5 s. Polarization levels of [2‐ 13 C]pyruvate and [1‐ 13 C]acetate were not significantly different after transfer to the scanner. In vivo, [1‐ 13 C]acetate and [1‐ 13 C]acetylcarnitine could be detected using spectroscopy and imaging. Conclusion Decarboxylation of hyperpolarized [2‐ 13 C]pyruvate enables the efficient production of highly polarized [1‐ 13 C]acetate that is applicable to study short‐chain fatty acid metabolism in the in vivo heart.