NAD+ Boosting Strategies.

Nicotinamide adenine dinucleotide (oxidized form, NAD⁺) serves as a co-substrate and co-enzyme in cells to execute its key roles in cell signalling pathways and energetic metabolism, arbitrating cell survival and death. It was discovered in 1906 by Arthur Harden and William John Young in yeast extract which could accelerate alcohol fermentation. NAD acts as an electron acceptor and cofactor throughout the processes of glycolysis, Tricarboxylic Acid Cycle (TCA), β oxidation, and oxidative phosphorylation (OXPHOS). NAD has two forms: NAD⁺ and NADH. NAD⁺ is the oxidising coenzyme that is reduced when it picks up electrons. NAD⁺ levels steadily decline with age, resulting in an increase in vulnerability to chronic illness and perturbed cellular metabolism. Boosting NAD⁺ levels in various model organisms have resulted in improvements in healthspan and lifespan extension. These results have prompted a search for means by which NAD⁺ levels in the body can be augmented by both internal and external means. The aim of this chapter is to provide an overview of NAD⁺, appraise clinical evidence of its importance and success in potentially extending health- and lifespan, as well as to explore NAD⁺ boosting strategies.