The protective effect of vitamin E on rats’ ovarian follicles following an administration of diazinon: An experimental study

Background: Diazinon (DZN) is an organophosphate insecticide that has been widely utilized in agriculture all over the world and caused many negative effects on different species such as plants and animal species, especially on a human. Objective: The aim of the present study was to evaluate the protective effect of vitamin E on rats’ ovarian follicles following an administration of diazinon. Materials and Methods: A total of 30 adult female Wistar rats were divided into five groups: a control group (without any intervention), sham group (received only pure olive oil, as solvent), experimental group I (DZN+olive oil, 60 mg/kg), experimental group II (vitamin E, 200 mg/kg), and experimental group III (DZN: 60 mg/kg+vitamin E: 200 mg/kg). All drugs were injected intraperitoneally, except vitamin E which was administrated by gavage. The animals were sacrificed after two weeks and the left ovary was used to measure proliferation of ovarian follicles. Tissues were analyzed by the PCNA technique and viewed with an optical microscope for evaluating cell proliferation. Results: The result of the present study revealed that the number of proliferative cells in the experimental group I decreased significantly in contrast to the control group in secondary and Graffian follicles (p< 0.001). The administration of vitamin E plus DZN significantly increased proliferative cells compared to the DZN group (p< 0.001). Primordial follicles showed that all study groups were lacking PCNA positive cells, which means no expression of PCNA in these follicles. The results of this study showed that primary follicles in all study groups had a few and scattered PCNA positive cells with no significant difference between the groups (p> 0.05). Conclusion: Results showed that DZN reduced proliferation in secondary and Graffian follicles and vitamin E increased it. The results of this study suggested that vitamin E by its antioxidant activity was able to improve the DZN-induced ovarian toxicity. Key words: Diazinon, Proliferation, Ovary, Vitamin E, Rat