GAPDH and diabetes mellitus: Previous studies have shown thathyperglycemia-induced oxidative stress leads to DNA damage and activation of nuclearpoly(ADP-ribose) polymerase (PARP, a nuclear DNA repair enzyme), which inhibits thecatalytic activity of glyceraldehyde 3-phosphate dehydrogenase (GAPDH).28,29 It issuggested that as a result the levels of glycolytic metabolites (e.g., MG, GAP andDHAP) that are upstream of GAPDH increase, resulting in activation of multiplepathogenic pathways in diabetes, such as activation of protein kinase C (PKC) and anincrease of AGEs.