Detection of cerebral NAD+ in humans at 7T

PurposeTo develop H-1-based MR detection of nicotinamide adenine dinucleotide (NAD(+)) in the human brain at 7T and validate the H-1 results with NAD(+) detection based on P-31-MRS. Methods(1)H-MR detection of NAD(+) was achieved with a one-dimensional double-spin-echo method on a slice parallel to the surface coil transceiver. Perturbation of the water resonance was avoided through the use of frequency-selective excitation. P-31-MR detection of NAD(+) was performed with an unlocalized pulse-acquire sequence. ResultsBoth H-1- and P-31-MRS allowed the detection of NAD(+) signals on every subject in 16min. Spectral fitting provided an NAD(+) concentration of 10728M for H-1-MRS and 367 +/- 78M and 312 +/- 65M for P-31-MRS when uridine diphosphate glucose (UDPG) was excluded and included, respectively, as an overlapping signal. ConclusionsNAD(+) detection by H-1-MRS is a simple method that comes at the price of reduced NMR visibility. NAD(+) detection by P-31-MRS has near-complete NMR visibility, but it is complicated by spectral overlap with NADH and UDPG. Overall, the H-1- and P-31-MR methods both provide exciting opportunities to study NAD(+) metabolism on human brain in vivo. (c) 2016 International Society for Magnetic Resonance in Medicine. Magn Reson Med 78:828-835, 2017. (c) 2016 International Society for Magnetic Resonance in Medicine.