Folic acid protects against fluoride-induced oxidative stress and testicular damage in rats

Objective: To investigate the effects of folic acid on testicular oxidative damage in sodium fluoride-induced male Wistar rats. Methods: A total of 24 male Wistar rats were divided into 4 groups: the control, sodium fluoride (fed with 100 mg/L sodium fluoride through drinking water orally for 21 days), folic acid (36 μg/kg body weight/day, orally), and sodium fluoride plus folic acid (received similar dose orally) groups. At the end of 21 days, epididymal sperm parameters, biochemical analysis of testicular tissue, and serum hormonal levels were performed along with histopathological studies. Results: Sodium fluoride intoxication resulted in marked reduction in gonado somatic index, serum luteinizing hormone, and testosterone level along with 3 β -hydroxysteroid dehydrogenase and 17 β -hydroxysteroid dehydrogenase activities. In addition, reduction in sperm density, as well as loss of sperm motility and sperm viability, were also observed. Besides, increased levels of testicular malondialdehyde, nitrite, interleukin-6 and tumor necrosis factor- α as well as decreased levels of superoxide dismutase and catalase activities and reduced glutathione content were found to be associated with this toxicity. Folic acid co-treatment, on the other hand, could prevent all the sodium fluoride-induced testicular pathophysiology and oxidative stress related parameters. Histological examinations of testicular sections from the experimental rats supported these results. Conclusions: Combining all, this study suggests that being an antioxidant, folic acid plays a beneficial role against fluoride-induced adverse effects on the male reproductive system.