Regulation of glucose storage extends lifespan and promotes healthspan

Western diets including an ever-increasing amount of sugar are attributing to the current alarming rise in obesity and Type 2 diabetes. Excess dietary sugar (glucose) is stored as glycogen in both humans and Caenorhabditis elegans (C. elegans). A key enzyme in glycogen synthesis in both humans and C. elegans is glycogen synthase, which in C. elegans is encoded by the gene gsy-1. Here, I will discuss our findings that show that dependent upon how excess dietary glucose is stored, can result either in detrimental or beneficial longevity and health effects. Limiting glycogen storage leads to a metabolic shift whereby glucose is now stored as trehalose. The increased trehalose requires a functional FOXO transcription factor DAF-16 and autophagy to promote lifespan and healthspan extension. Taken together, excess dietary glucose stored as glycogen is detrimental, whereas, when stored as trehalose, animals live a longer, healthier life.