PRKAA2 and diabetes mellitus: The importance of AMPK in the development of endothelial dysfunction and atherosclerosis is best demonstrated by recent studies showing that metformin, one of the most used anti-diabetic drugs which was recently to exert its therapeutic effect in diabetes by activating AMPK [42], [43], has been shown to improve vascular functions and to dramatically reduce cardiovascular endpoints and mortality for type II diabetic patients in large scale clinical trials [44], [45], [46].