INS and hyperinsulinism: Akt2 knockout mice exhibited a diabetic phenotype accompanied by hyperglycemia, impaired INS action, reduced circulating leptin, and mild growth retardation (George et al. 2004), whereas Akt2 and Akt3 double knockout mice exhibited hyperinsulinemia, hyperglycemia, and reduced brain volume (Dummler et al. 2006).