Abstract
PURPOSE: To develop (1) H-based MR detection of nicotinamide adenine dinucleotide (NAD(+) ) in the human brain at 7T and validate the (1) H results with NAD(+) detection based on (31) P-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. (31) P-MR detection of NAD(+) was performed with an unlocalized pulse-acquire sequence. RESULTS: Both (1) H- and (31) P-MRS allowed the detection of NAD(+) signals on every subject in 16 min. Spectral fitting provided an NAD(+) concentration of 107 ± 28 μM for (1) H-MRS and 367 ± 78 μM and 312 ± 65 μM for (31) P-MRS when uridine diphosphate glucose (UDPG) was excluded and included, respectively, as an overlapping signal. CONCLUSIONS: NAD(+) detection by (1) H-MRS is a simple method that comes at the price of reduced NMR visibility. NAD(+) detection by (31) P-MRS has near-complete NMR visibility, but it is complicated by spectral overlap with NADH and UDPG. Overall, the (1) H- and (31) P-MR methods both provide exciting opportunities to study NAD(+) metabolism on human brain in vivo. © 2016 International Society for Magnetic Resonance in Medicine. Magn Reson Med 78:828-835, 2017. © 2016 International Society for Magnetic Resonance in Medicine.