Taurine reverses sodium fluoride-mediated increase in inflammation, caspase-3 activity, and oxidative damage along the brain-pituitary-gonadal axis in male rats.

Excessive exposure to fluoride is associated with male reproductive dysfunction in humans and animals. Taurine (2-aminoethane sulfonic acid) is a free intracellular ß-amino acid with antioxidant, anti-inflammatory, and neuroprotective properties. However, the effect of taurine on fluoride-induced reproductive toxicity has not been reported. The present study investigated the influence of taurine on sodium fluoride (NaF)-induced functional changes along the brain-pituitary-gonadal axis in male rats. NaF was administered singly in drinking water at 15 mg·L-1 alone or orally co-administered by gavage with taurine at 100 and 200 mg·(kg body mass)-1 for 45 consecutive days. Results showed that taurine significantly prevented NaF-induced increase in oxidative stress indices as well as augmented antioxidant enzymes activities and glutathione level in the brain, testes, and epididymis of the treated rats. Moreover, taurine reversed NaF-induced elevation in inflammatory biomarkers and caspase-3 activity as well as histological damage in the brain, testes, and epididymis of the treated rats. The significant reversal of NaF-induced decreases in testosterone level and testicular activities of acid phosphatase, alkaline phosphatase, and lactate dehydrogenase by taurine was accompanied by enhancement of sperm functional characteristics in the treated rats. Taurine may be a possible chemopreventive candidate against reproductive dysfunction resulting from fluoride exposure.

Neuroprotective influence of taurine on fluoride-induced biochemical and behavioral deficits in rats.

Epidemiological and experimental studies have demonstrated that excessive exposure to fluoride induced neurodevelopmental toxicity both in humans and animals. Taurine is a free intracellular ß-amino acid with antioxidant and neuroprotective properties. The present study investigated the neuroprotective mechanism of taurine by evaluating the biochemical and behavioral characteristics in rats exposed to sodium fluoride (NaF) singly in drinking water at 15 mg/L alone or orally co-administered by gavage with taurine at 100 and 200 mg/kg body weight for 45 consecutive days. Locomotor behavior was assessed using video-tracking software during a 10-min trial in a novel environment while the brain structures namely the hypothalamus, cerebrum and cerebellum of the rats were processed for biochemical determinations. Results showed that taurine administration prevented NaF-induced locomotor and motor deficits namely decrease in total distance travelled, total body rotation, maximum speed, absolute turn angle along with weak forelimb grip, increased incidence of fecal pellets and time of grooming, immobility and negative geotaxis. The taurine mediated enhancement of the exploratory profiles of NaF-exposed rats was supported by track and occupancy plot analyses. Moreover, taurine prevented NaF-induced increase in hydrogen peroxide and lipid peroxidation levels but increased acetylcholinesterase and the antioxidant enzymes activities in the hypothalamus, cerebrum and cerebellum of the rats. Collectively, taurine protected against NaF-induced neurotoxicity via mechanisms involving the restoration of acetylcholinesterase activity and antioxidant status with concomitant inhibition of lipid peroxidation in the brain of rats.