Deuterium labeling kinetics in rat cerebral cortex using ex-vivo 2H NMR spectroscopy

Motivation: Lower sensitivity of 13C NMR spectroscopy requires longer acquisition time while quantifying brain metabolites. An alternative technique is essential to aid faster detection. Goal(s): To evaluate the kinetics of 2H labeling brain metabolites from [6,6’-2H2]glucose using 2H NMR spectroscopy. Approach: The cortical extracts of rats infused with [6,6’-2H2]glucose were analyzed using 2H NMR spectroscopy. Results: The signals of deuterated GlcC6, GluC4, LacC3, GABAC2and GlnC4 are seen in the 2H NMR spectrum of cortical extract obtained after 90 min of [6,6’-2H2]glucose infusion. The resonances of AspC2, GluC2, and GluC3 are absent suggesting complete loss/dilution of 2H from the TCA cycle intermediates beyond α-ketoglutarate. Impact: Judicious use of 2H NMR together with suitable deuterated substrates may an alternative for neurometabolic analysis in neurological disorders.