Loss of NAD homeostasis leads to progressive and reversible degeneration of skeletal muscle
Nad is an important coenzyme for cell energy conversion. In the process of glycolysis and oxidative phosphorylation, it depends on the electron shuttle characteristics of nicotinamide adenine dinucleotide (NAD + or NAD), which requires strict control of the balance between the synthesis and degradation of this dinucleotide in cells. However, in the process of genotoxic stress and natural aging, the level of NAD decreases in multiple tissues with age or disease, and the availability of NAD in some tissues will be limited. The functional impact of NAD restriction on tissue physiology remains unclear. Nicotinamide (NAM) is a precursor of NAD, and most tissues cannot synthesize Nam from scratch. Therefore, most mammalian cells must rely on remedial pathways to regenerate degraded NAD. Therefore, one of the strategies to expand the nad remedial synthesis pathway is to supplement the diet with compounds containing Nam, including nicotinamide mononucleotide (MN) and nicotinamide nucleoside (NR).