Carnosine and vitamin E - a promising pair in the combat against testicular oxidative stress in aged rats

Abstract

Oxidative stress is considered to play a key role in ageing. Carnosine alone or together with vitamin E may prove to be helpful in dealing with problems of ageing through its antioxidant activity. Testis, by producing steroids and possessing a poor antioxidant system may become a strong target for the chronic oxidative stress generated during ageing. Therefore we investigated the in vivo effect of carnosine alone or together with vitamin E on testicular oxidative stress in aged rats. In this study, young (5 months) and aged (22 months) Wistar rats were used. Carnosine (250 mg kg(-1); i.p.; 5 days per week) and vitamin E (200 mg kg(-1); i.m.; twice per week) were given to aged rats for 2 months. Increased testicular lipid peroxidation and superoxide dismutase activity in aged rats were declined to the levels of young ones by both treatments. Decreased glutathione peroxidase and glutathione transferase activities returned to the level of young's only by carnosine plus vitamin E treatment. Histopathological evaluation described by Johnsen's score, also showed significant improvement with preserved spermatogenesis. Carnosine plus vitamin E treatment appears to stage a powerful performance by attenuating testicular oxidative stress and sparing the antioxidant system.

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

“…CAR is also found to improve JS with preserved spermatogenesis, which has also been observed in the study of Aydın et al. () in naturally aged rats. These results may clearly indicate the beneficial role of CAR on disrupted testicular function during ageing.…”

“…Testicular dysfunction due to gamma‐radiation was shown to be restored by CAR through its anti‐apoptotic action (Haeri, Rajabi, Fazelipour, & Hosseinimehr, ). In a previous study, increased testicular TBARS and DC levels in naturally aged rats were found significantly decreased by CAR and CAR + Vit E treatments (Aydın et al., ). To our knowledge, the effect of CAR on testicular oxidative stress and glycation in GAL‐induced aged animals is not presented in the literature.…”

“…Endogenous testosterone plays a crucial role in the maintenance of this balance (Liao et al., ). Testosterone levels were reported to decrease during natural (Aydın et al., ) and GAL‐induced ageing (Jeremy, Gurusubramanian, & Roy, ; Yang, Du et al., ). This decrease is considered to be related to oxidative stress‐induced damage of Leydig cells (Zirkin & Tenover, ).…”

“…The treatment period was 2 months. GAL and CAR doses were chosen according to our previous studies (Aydın et al., , ).…”

“…In a previous study, CAR and its combination with vitamin E (Vit E) were found to attenuate testicular oxidative stress together with histopathological improvement in naturally aged rats (Aydın et al., ). There appears to be no study about the in vivo effects of CAR on testicular oxidative stress and protein glycation in rats aged by GAL in literature.…”