Increased receptor for advanced glycation end products in spermatozoa of diabetic men and its association with sperm nuclear DNA fragmentation.

Although the majority of patients with diabetes have disorders in sexual function, associations between diabetes mellitus and sperm function at the molecular level are largely unknown. As receptor for advanced glycation end products plays a key role in many diabetic complications, we hypothesised that it may be involved in sperm nuclear DNA fragmentation. RAGE levels were determined using ELISA and western blot analysis in sperm samples from 32 diabetic and 35 nondiabetic men. Sperm DNA fragmentation was assessed using TUNEL assay. Diabetic men had significantly higher mean levels of RAGE protein (P < 0.001) and DNA fragmentation (P < 0.001) in spermatozoa. Sperm RAGE was directly correlated to sperm DNA fragmentation in diabetic men (r = 0.81, P < 0.001). The high positive correlation between RAGE levels and nuclear DNA fragmentation in spermatozoa of diabetic men suggests a central role of RAGE in disturbances in sexual function of diabetic men.