Carnosine prevents testicular oxidative stress and advanced glycation end product formation in D-galactose-induced aged rats.

D-Galactose is shown to mimic natural ageing in rodents by exacerbating oxidative stress and glycation. Steroid production and having a poor antioxidant system make testis vulnerable to galactose-induced ageing. Antioxidation and antiglycating actions of carnosine may be intriguing for prevention of testicular ageing. In this study, male Wistar rats were applied D-galactose (300 mg/kg; subcutaneously 5 days a week) and carnosine (250 mg/kg; intraperitoneally 5 days a week) along with D-galactose for 2 months. D-Galactose treatment increased testicular reactive oxygen species, thiobarbituric acid reactive substances, diene conjugates, protein carbonyls, advanced oxidation products of proteins and advanced glycation end products. Carnosine was capable of repelling oxidative stress and glycation produced by D-galactose. Johnsen's score, which describes histopathological evaluation, was also significantly improved with preserved spermatogenesis by carnosine. It appears that carnosine deters the testicular oxidative stress due to galactose-induced ageing directly by its antioxidative and antiglycating properties.