NMNAT1 inhibits axon degeneration via blockade of SARM1-mediated NAD+ depletion - PubMed (original) (raw)
(a) Intracellular NMN and NAD+ levels relative to control (0 hr) were quantified at 2, 4, and 6 hr after 100 nM FK866 addition using LC-MS/MS. Data show the first and third quartile (box height) and median (line in the box) ± 1.5 time interquartile (details in the method), one-way ANOVA F(3,8) = 12.9, p=0.00197 for NMN; F(3,8) = 6.541, p=0.0152 for NAD+. *p<0.05 denotes significant difference from metabolite levels at 0 hr with Holm-Bonferroni multiple comparison (Figure 2—source data 1, n=3). (b, c) Intracellular NMN and nicotinic acid mononucleotide (NaMN) levels (b), and NAD+ and nicotinic acid adenine dinucleotide (NaAD) levels (c) relative to control (for NMN, NAD+) or relative to NMN DD-expressing neurons (for NaMN, NaAD) were measured using LC-MS/MS. Data show the first and third quartile (box height) and median (line in the box) ± 1.5 time interquartile (details in the method), one-way ANOVA F(6, 35)=369.8, p<2× 10–16 for NaMN; F(6, 35) = 29.92, p=2.14×10–12 for NMN; F(6, 35) = 537, p<2×10–16 for NaAD; F(6, 35) = 33.69, p=3.83× 10–13 for NAD. *p<0.05, **p<1×10–4 denote a significant difference from control metabolite levels with Holm-Bonferroni multiple comparison (Figure 2—source data 1, n = 6). (d, e) Axonal NAD+ (d) and NMN (e) were quantified at 0, 1, 2, 3, and 6 hr post axotomy using LC-MS/MS. Axonal metabolites were collected from transected axons at the indicated time after axotomy. Data show the first and third quartile (box height) and median (line in the box) ± 1.5 time interquartile (details in the method), one-way ANOVA F(4,10) = 193.6, p=2×10–9 for control NAD+; F(4,10) = 6.682, p=6.694×10–3 for control NMN; F(4,10) = 28.87, p=1.87×10–5 for NRK1 NR, NAD+; F(4,10) = 24.49, p=3.78×10–5, for NRK1+ NR NMN. There are no significant metabolite changes after axotomy for NAMPT, cytNMNAT1, or NMN DD expressing cells (F(4, 10) = 1.066, p=0.422 for NAMPT NAD+, F(4,10) = 0.893, p=0.503 for NAMPT NMN, F(4,10) = 0.127, p=0.969 for cytNMNAT1 NAD+, F(4,10)=0.366, p=0.828 for cytNMNAT1 NMN, F(4,10)=0.343, p=0.843 for NMN DD NAD+, F(4,10) = 0.004, p=1 for NMN DD NMN). *p<0.05, **p<1×10–4 denote significant difference from axonal metabolite levels at 0 hr post axotomy with Holm-Bonferroni multiple comparison (Figure 2—source data 1, n = 3). # p<0.05 denotes significant difference of baseline NAD+ or NMN before axotomy compared with control; One-way ANOVA with Holm-Bonferroni multiple comparison, F(4, 10) = 10.8, p=0.0012 for NAD+ and F(4,10) = 41.44, p=3.1×10–6 for NMN (Figure 2—source data 1, n = 3). DOI: