The effect of di-n-butyl phthalate on testis and the potential protective effects of resveratrol.

This study aimed to observe the possible protective effects of resveratrol (RSV) against the damage of di-n-butyl phthalate (DBP) on the testis. The study was conducted in 6 groups of rats with 6 animals in each group aged 20 days. The groups include group 1: control group; group 2: solvent (carboxymethylcellulose (CMC), 10 ml/kg); group 3: 500 mg/kg/day DBP; group 4: 500 mg/kg/day DBP + 20 mg/kg/day RSV; group 5: 1000 mg/kg/day DBP; and group 6: 1000 mg/kg/day DBP + 20 mg/kg/day RSV. Groups were treated by gavage for 30 days. Indirect immunohistochemical staining was performed with c-kit, AT1, and ER-α antibodies. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling (TUNEL) method was used for apoptosis. It was found in the DBP-applied groups the C-kit immunostaining, which is parallel to increasing dose, decreased in comparison with the control. C-kit reactivity was similar to that of the control group in the group applied with 500 mg/kg/day + RSV; however, the reactivity was not same in the 1000 mg/kg/day DBP-applied group. It was observed that the reactivity of AT1 increased in the DBP-applied groups. RSV reversed these changes with its protective effects. While there was not much difference between the groups in terms of estrogen receptor reactivity, it was observed that the high dose of DBP reduced the level of estrogen receptor and the resveratrol was not at enough levels in all doses. In TUNEL analysis, high doses of DBP increased the apoptosis in all types of cells; nevertheless, the resveratrol application decreased the apoptosis in the low-level DBP dose. In the statistical analysis, while the length of epithelium and the diameter of seminiferous tubules decreased for all the other groups, it reverted to its original state in the RSV-applied groups. In conclusion, DBP (with increasing dose) administration caused cycle and hormonal changes in testis, resveratrol were recovered the cyclic changes but in hormonal changes, RSV is efficient too but inadequate.