GW-0742 vs NAD+

Metabolic

Metabolic

Research Only

Research Only

GW-0742 is a high-affinity, highly selective agonist of human PPARδ (EC50 = 1.1 nM for hPPARδ transactivation vs ~1.1 µM for hPPARα and ~2 µM for hPPARγ), conferring ~1000-fold selectivity for PPARδ over the other PPAR subtypes. Upon activation, PPARδ heterodimerizes with RXR and binds PPAR-response elements (PPREs) to alter transcription of genes governing fatty-acid oxidation, glucose utilization, and inflammatory signaling. In mice, however, GW-0742-induced hepatomegaly, hepatic/skeletal-muscle peroxisome proliferation, and skeletal myopathy were shown to be predominantly mediated by off-target PPARα cross-activation rather than PPARδ—a mechanism-based toxicity concern at animal-study exposures.

NAD+ functions as a primary electron carrier in glycolysis, the TCA cycle, and oxidative phosphorylation. Beyond its redox role, NAD+ serves as a consumable substrate for sirtuin deacetylases (SIRT1-7), poly(ADP-ribose) polymerases (PARPs), and CD38/CD157 ectoenzymes. Sirtuin activation is linked to mitochondrial biogenesis, autophagy, and stress-response gene expression, and PARP activity is central to DNA-damage repair. Oral bioavailability of intact NAD+ is poor, which is why clinics market IV infusion; the best human data for raising tissue NAD+ involve oral precursors NR (nicotinamide riboside) and NMN (nicotinamide mononucleotide) rather than NAD+ itself.