Ethyl Pyruvate Prevents Renal Damage Induced by Methylglyoxal-Derived Advanced Glycation End Products

The renal accumulation of advanced glycation end products (AGEs) is a causative factor of various renal diseases, including chronic kidney disease and diabetic nephropathy. AGE inhibitors, such as aminoguanidine and pyridoxamine, have the therapeutic activities for reversing the increase in renal AGE burden. This study evaluated the inhibitory effects of ethyl pyruvate (EP) on methylglyoxal- (MGO-) modified AGE cross-links with proteins in vitro. We also determined the potential activity of EP in reducing the renal AGE burden in exogenously MGO-injected rats. EP inhibited MGO-modified AGE-bovine serum albumin (BSA) cross-links to collagen (IC50=0.19 +/- 0.03 mM) in a dose-dependent manner, and its activity was stronger than aminoguanidine (IC50=35.97 +/- 0.85 mM). In addition, EP directly trapped MGO (IC50=4.41 +/- 0.08 mM) in vitro. In exogenous MGO-injected rats, EP suppressed AGE burden and MGO-induced oxidative injury in renal tissues. These activities of EP on the MGO-mediated AGEs cross-links with protein in vitro and in vivo showed its pharmacological potential for inhibiting AGE-induced renal diseases.