Evaluation of the possible protective effect of aloe vera against reproductive toxicity induced by diazinon in adult albino rats

ABSTRACT

Diazinon, an organophosphate insecticide has been used in agriculture and domestic for several years. This work was undertaken to investigate the toxic effects of diazinon on reproductive systems in adult albino rats of both sexes and to assess the protective effects of aloe vera against these toxic effects. A total of 60 adult albino rats of both sexes were equally divided into five groups. Twelve rats served as the negative control [group 1], another twelve rats were used as positive control group [group 2] received deionized water [the vehicle]. The remaining thirty-six rats were equally divided into three groups. Rats in group 3 were treated with aloe vera in a dose of 300 mg/kg, while those of group 4 received 12.8 mg/kg of diazinon. Rats in the 5[th] group were treated with aloe vera followed by diazinon. For each group, it was further subdivided into two subgroups; a-subgroup for male rats and bsub group for female rats. Chemicals and vehicle were administered by gavage on a daily base for eight weeks. By the end of the study, all rats were sacrificed for collection of blood samples for evaluation of testosterone, estradiol and progesterone. Testicular and ovarian specimens were collected for assessment of oxidative stress markers and histopathological examination. Diazinon significantly reduced the serum levels of testosterone in male rats and estradiol and progesterone in female rats. Diazinon induced disorganized degenerated germinal epithelium with edema between the seminiferous tubules and degeneration of the corpora lutea and ovarian follicles. These changes were accompanied with increased caspase-3 immunoreactivity and significant decreases in testicular and ovarian glutathione [GSH] levels, activity of superoxide dismutase [SOD] enzyme and a significant increase in malonaldehyde levels. Also it was observed that aloe vera treatment diminished diazinon induced detrimental effects in both testis and ovary. Diazinon induced testicular and ovarian damage might be due to oxidative stress and free oxygen radicals production upon diazinon exposure, inducing histopathological alterations and promoting local apoptosis via activation of caspase-3 pathway; however, aloe vera seems to be an effective antioxidant against diazinon induced testicular and ovarian toxicity