INS and diabetes mellitus: With respect to skeletal muscle tissues of the Goto-Kakizaki rat, numerous studies have clearly shown diabetes-related abnormalities, including (i) an inhibition of insulin receptor autophosphorylation [107], (ii) abnormal functioning of insulin signaling intermediates [108, 109], (iii) an altered subcellular localization and diminished recruitment of the main glucose transporter GLUT4 [110], (iv) cytoskeletal defects in the sarcolemmal dystrophin-dystroglycan complex [111], (v) a significantly reduced percentage of oxidative fibres [112], and (vi) abnormal mitochondrial functioning [113].