NAD+ proton T1 and T2 relaxation measured in vivo in the human brain at 7T using single-slice spectrally-selective downfield MRS

Motivation: NAD+ is a key metabolite in aging and disease, but its absolute in vivo tissue quantification requires correction for T1 and T2 relaxation effects. Goal(s): Our goal was to determine T1 and T2 of NAD+ in human brain in vivo at 7T. Approach: We utilized spectrally-selective downfield spectroscopy with slice localization. Results: We measured an average T1 of 164.6±28.1ms and an average T2 of 33.5±10.3ms across three NAD+ downfield resonances. Impact: Our measurements of NAD+ T1 and T2 in human brain can be used as correction factors to quantify absolute concentration of NAD+, a potential biomarker to study metabolic derangements in many diseases.