Small amounts of dietary fructose dramatically increase hepatic glucose uptake through a novel mechanism of glucokinase activation.

Glucokinase plays a major role in the control of hepatic glucose uptake and storage as glycogen. Small amounts of fructose-1-phosphate, in the presence of relatively high glucose levels, markedly stimulate glucokinase through a novel mechanism of regulation involving dissociation from a regulatory protein and translocation from the nucleus into the cytosol. Using this understanding of glucokinase regulation, a recent study demonstrated that very small amounts of fructose (infused into the duodenum) could increase hepatic glucose uptake and glycogen storage, and reduce peripheral glycemia and insulin levels in the dog. These results suggest that very small amounts of dietary fructose could be beneficial in type 2 diabetes.