These deleterious alterations can be normalized by administering NMN.444 Furthermore, NMN alienates glucose intolerance and lipid profiles by recovering NAD+ levels in age induced T2D mouse model.337 Conversely, overexpression of Nmnat3 in mouse can effectively increase NAD+ levels in a variety of tissues and prevent aging-related insulin resistance caused by diet.360 Owing to its expression and activity increase with age, CD38 is essential for age-associated NAD+ decrease through degradation of NMN in vivo. Here, CD38 is linked to Glucose intolerance.