Induction of Oxidative Stress on Reproductive and Metabolic Organs in Sodium Fluoride-Treated Male Albino Rats: Protective Effect of Testosterone and Vitamin E Coadministration

Abstract

The present study was undertaken to search out the effect of sodium fluoride, a water pollutant noted throughout the world, including India, on oxidative stress induction in reproductive tissues, sperm pellet, and metabolic tissues like the liver and kidney. The protective effects of testosterone or vitamin-E coadministration were also observed on oxidative stress in the above mentioned samples. A significant diminution was noted in the activities of catalase and peroxidase, important antioxidant enzymes in testicular tissue, sperm pellet, prostate, and epididymis in sodium fluoride-treated rats at the dose of 20 mg/kg body weight/day (the level noted in drinking water in fluoride intoxicated areas) for 30 days by oral gavage. Coadministration of testosterone by intraperitoneal injection at the dose of 40 μg/100 g body weight/alternate day, 3 hours after fluoride treatment, resulted in a significant protection in the above mentioned parameters of all these samples. Moreover, fluoride treatment also resulted a significant elevation in the level of malondialdehyde and conjugated dienes, indicators of oxidative stress, in all the above mentioned samples, which were resettled toward the control level after testosterone coadministration. Testiculo-somatic, prostato-somatic, and epididymo-somatic indices were decreased significantly in the fluoride-treated group when compared to the vehicle-treated control group. Testosterone coadministration resulted in significant restoration of these indices to the control level. We also measured the above parameters for the evaluation of oxidative stress in the liver and kidney, important metabolic organs, and noted that there was also a significant elevation in malondialdehyde and conjugated dienes along with diminution in catalase and peroxidase activities in the fluoride treated-group, with respect to the vehicle treated control group. Testosterone coadministration resulted a significant protection in these parameters toward the vehicle-treated control level. There was no significant change in hepato-somatic and reno-somatic indices among fluoride-treated, testosterone coadministered, and vehicle-treated rats. Body weight of the animals among these three groups were not changed significantly. To find out the antioxidative property of testosterone compared to vitamin E, one group of fluoride-treated animals were subjected to coadministration of vitamin E at the dose of 20 mg/100 g body weight. It was noted that in reproductive organs and in metabolic organs, oxidative stress parameters were recovered toward the control level. The results of our experiment suggests that fluoride at the dose noted in drinking water in contaminated areas may induce oxidative stress in reproductive and metabolic organs that can be ameliorated significantly by testosterone or vitamin E coadministration. Moreover, as there was no significant variation in body weights among these groups, it may be predicted that this effect of fluoride on reproductive and metabolic organs is specific and is not due to general effect of fluoride.