Boosting NAD⁺ with a small molecule that activates NAMPT.

Abstract

Pharmacological strategies that boost intracellular NAD⁺ are highly coveted for their therapeutic potential. One approach is activation of nicotinamide phosphoribosyltransferase (NAMPT) to increase production of nicotinamide mononucleotide (NMN), the predominant NAD⁺ precursor in mammalian cells. A high-throughput screen for NAMPT activators and hit-to-lead campaign yielded SBI-797812, a compound that is structurally similar to active-site directed NAMPT inhibitors and blocks binding of these inhibitors to NAMPT. SBI-797812 shifts the NAMPT reaction equilibrium towards NMN formation, increases NAMPT affinity for ATP, stabilizes phosphorylated NAMPT at His247, promotes consumption of the pyrophosphate by-product, and blunts feedback inhibition by NAD⁺. These effects of SBI-797812 turn NAMPT into a "super catalyst" that more efficiently generates NMN. Treatment of cultured cells with SBI-797812 increases intracellular NMN and NAD⁺. Dosing of mice with SBI-797812 elevates liver NAD⁺. Small molecule NAMPT activators such as SBI-797812 are a pioneering approach to raise intracellular NAD⁺ and realize its associated salutary effects.