Evaluation of histologic, antiapoptotic and antioxidant effects of melatonin against the acute ocular toxicity of Cisplatin.

This study aimed to investigate the protective effect of melatonin against the acute toxicity of cisplatin in ocular tissues. The eyes of 40 rats were divided into 4 groups: Control group (10 rats), Melatonin (Mel) group (10 rats), Cisplatin (Cis) group (10 rats), Melatonin (Mel) + Cisplatin (Cis) group (10 rats). Retina, cornea, and ciliary body tissues were examined after hematoxylin-eosin staining of sections obtained from the eyes and were scored for disorganization and degeneration. Apoptotic cells were counted for the retina, cornea, and ciliary body with the TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling) method. The total antioxidant status (TAS) / total oxidant status (TOS) of homogenized eye tissues were measured. While apoptotic cells were found to increase in the cornea of the Cisplatin (Cis) group, no difference was found regarding the retina and ciliary body cell count. An increased number of apoptotic cells in the cornea of the Cis group was found while there was a decrease in the group where Cisplatin and Melatonin were administered together (Mel+Cis group). There was no statistically significant difference amongst groups for TOS or TAS. Melatonin had a partial protective effect against histological damage.