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Background: Nicotine is a toxic compound in the cigarette smoke and has destructive effects on various human organs. Astaxanthin is a carotenoid with high antioxidant property. In this study, we investigated the protective effects of astaxanthin against nicotine-induced toxicity in mice testes.
Methods: Forty-two inbred balb/c male mice were divided into six groups:Group 1, received 1 ml normal saline daily; Group 2, received nicotine (1.5mg/kg); Group 3, received astaxanthin (25mg/kg); Group 4, received astaxanthin (50mg/kg); Group 5, received astaxanthin (25mg/kg) plus nicotine (1.5mg/kg); and group 6, received astaxanthin (50mg/kg) plus nicotine (1.5mg/kg). After collecting testes samples, microscopic slides were prepared at the School of Veterinary Medicine, University of Mashhad, and the prepared slides were examined under light microscopy.
Results: The histological structures of the testes were normal in the control group and those receiving astaxanthin, regardless of nicotine (groups 3, 4, 5 & 6).  However, group 2 that received only nicotine, showed transformed testicular histology with severe hemorrhage.
Conclusion: Based on the results, nicotine caused harmful effects on the mice testes and astaxanthin appeared to protect the organs against the toxic effects of nicotine.