TNF and metabolic dysfunction-associated steatotic liver disease: The replenishment of NAD, by treated with NR, is able to protect against aging-induced hepatic steatosis, which is possibly associated with an improvement in reduction of pro-inflammatory cytokines, such as IL-1β and TNF- α. Our study raises the possibility of NR to alleviate NAFLD-like liver injure in aged individuals, suggesting the clinical advantage of NR during vitamin supplementation therapy.