As the average human lifespan increases, people are experiencing poor health and age-related diseases longer, incurring major financial and societal costs. One substantial contributing factor to age-related diseases and their progression is degraded immune function. Specifically, NK cells that terminate cancer and virally infected cells become less effective. At present, no remedy exists to restore the function of NK cells during aging. So, compounds that stimulate NK cell activation may prevent age-related ailments or slow their advancement.
Okumura and colleagues from Juntendo University in Japan treated mice with nicotinamide mononucleotide (NMN) to restore NK cell cytotoxicity — the ability to destroy malfunctioning cells. Published in Biomedical Research, NK cell stimulation in mice occurred when NMN was injected (313, 625, or 1250 mg/kg) or orally administered (625 mg/kg) for four days. Notably, the boosted NK cell cytotoxicity didn’t come from their enhanced proliferation or higher NK cell numbers but rather improved NK cell abilities to destroy cancer cells. These findings support that NMN supplementation may boost NK cell immunity and overall tissue health by curtailing the accumulation of precancerous and viral-infected cells as people age.