Abstract
Fluoride is a highly electronegative anion with cumulative toxic effects causing reproductive dysfunction and increase in reactive oxygen species production in different organs including testis. Propolis is a honeybee product that has an antioxidant property. The aim of this study was to elucidate the protective effects of propolis against reproductive toxicity induced by sodium fluoride (NaF) in male rabbits (buck). Four experimental groups receiving a combination of sodium fluoride (10 mg/ kg body weight/day) and/or propolis (25 mg/ kg body weight/day) for 70-day was divided as follows: non treated (control), sodium fluoride alone, propolis alone and sod fluoride + propolis. Sodium fluoride caused a decrease in testes and epididymis weights as well as serum testosterone and accompanied with disturbances in semen quality and quantity, compared to control group. Similarly, histopathological results revealed that NaF caused alterations in the testes, epididymis and prostate gland. There was intensive positive immunoreactivity for caspase- 3 (dark brown granules) was observed in the cytoplasm of germinal cells, Sertoli cells and Leydig cells of NaF treated group compared with the control that indicating the severity of its toxicity in testes. On the other hand, testicular cells of NaF in combination with propolis treated group showed apparent reduction of caspase-3 immunoreactivity to be more or less similar to the control group. Administration of propolis either alone or combined with NaF ameliorated these toxic effects. Testis of control group and propolis only revealed negative or low caspase- 3 immunohistochemical reactivity. In conclusion, propolis reduced the oxidative stress toxicity induced by fluoride in the reproductive system of male albino rabbits.

Key words: Sodium Fluoride, propolis; reproductive toxicity, immunohistopathology