Proteomics and phosphoproteomics of the diurnal cycle in chow and high fat high sucrose feed rats

There is growing evidence that energy metabolism and insulin action are regulated by mechanisms that follow a diurnal rhythm and it has been proposed that defects in Akt signalling are associated with the pathophysiology of metabolic disease. It is therefore important to investigate these parameters under physiology of the free-living state. We therefore examined the insulin action in muscle of chow or high fat, high sucrose diet-fed (HFHS) rats during the normal diurnal cycle. HFHS animals displayed hyperinsulinemia, however had reduced systemic glucose disposal and impaired muscle glucose uptake during the feeding period. Proteomics and phosphoproteomics was performed over the diurnal cycle in chow and HFHS rats.