Glycogen debranching enzyme and progressive muscle involvement, with variations caused by age of onset, rate of disease progression and severity. Patients with Type IIIb generally symptoms related to liver disease. Type III patients be distinguished by elevated liver enzymes, with normal uric acid and blood lactate levels, differing from other forms of GSD. In patients with muscle involvement, Type IIIa, the muscle weakness becomes predominant into adulthood and can lead to ventricular hypertrophy and distal muscle wasting. Glycogen debranching enzyme A debranching enzyme is a molecule that helps facilitate the breakdown of glycogen, which serves as a store of glucose in the body,
Glycogen synthase protein phosphatase 1 (PP1), which activates glycogen synthase via dephosphorylation. PP1 is targeted to the glycogen pellet by four targeting subunits, G, G, PTG and R6. These regulatory enzymes are regulated by insulin and glucagon signaling pathways. Mutations in the "GYS1" gene are associated with glycogen storage disease type 0. In humans, defects in the tight control of glucose uptake and utilization are also associated with diabetes and hyperglycemia. Patients with type 2 diabetes normally exhibit low glycogen storage levels because of impairments in insulin-stimulated glycogen synthesis and suppression of glycogenolysis. Insulin stimulates glycogen synthase by inhibiting glycogen synthase kinases