Biochemical and histopathological evaluations of ghrelin effects following cadmium toxicity in the rat testis

Numerous reports demonstrate that cadmium (Cd) induces oxidative stress by increasing lipid peroxidation and altering antioxidative enzymes status. Thirty male rats were subdivided into control-saline, Cd-saline and Cd-ghrelin groups. A single dose of Cd was injected to induce testicular injury and also ghrelin for 10 consecutive days to group 3. SOD activity decreased and lipid peroxidation increased by Cd administration. The mean activities of GPx and CAT as well as GSH content were lower in the Cd-saline rats; however, they did not statistically differ compared with the controls. Exposure to Cd resulted in complete degeneration of seminiferous tubules with severe depletion of germ cells and arrest in spermatogenesis. Notably, ghrelin treatment not only prevented reduction in SOD, GPx, CAT and GSH level, but also increased enzyme activities form their normal values. Moreover, TBARS concentration was significantly reduced by ghrelin administration. Furthermore, ghrelin pre-treatment resulted in partial but not significant prevention in testicular histopathological features damaged by Cd. In conclusion, the obtained results indicate for the first time the novel evidences of ghrelin ability in promotion of antioxidant enzyme activities and reduction of lipid peroxidation following Cd-induced oxidative stress in the rat testis. These observations also demonstrate that ghrelin may be considered as promising antioxidant agent in prevention and attenuation of testicular injury upon Cd toxicity.