However, C-peptide has been reported to play a protective role in complications associated with diabetes (Bhatt et al., 2014); the multidimensional effects of C-peptide in animals and patients with diabetes are associated with multiple cell signaling pathways, including extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt (Bhatt et al., 2014). This evidence concerns the gene MAPK3 and diabetes mellitus.