Fig. 6.

Proteomic Assessment of NAMPT Knockdown and NR or NMN Co-Treatment in Human Immortalized Myotubes.

Given that NAMPT protein is upstream of both SIRT1 and SIRT2 activity by virtue of their reliance on NAD, we next knocked down NAMPT in human myotubes as confirmed by western blots and quantification by TMT mass spec. A - C). GLO1 was also found to be ∼30 % lower in myotubes treated with NAMPT siRNA which was not rescued by either NR or NMN co-treatment. Globally, PCA plots in E) and hierarchical clustering in F and G) demonstrate a largely ineffectiveness of both NR and NMN to rescue the proteomic changes of NAMPT siRNA treatment. Volcano plots comparing NAMPT siRNA (H), NAMPT siRNA + NR (I), and NAMPT siRNA + NMN (J) to scRNA treated cells also demonstrates similar protein changes in the attempted rescue experiments as the siRNA alone. This is further exemplified in dot plots (K–M) depicting enrichment for similar GO and KEGG pathway terms across all 3 experiments.