Protection of Taurine Against Impairment in Learning and Memory in Mice Exposed to Arsenic

To evaluate protection of taurine against arsenic (As)-induced impairment of learning and memory as well as explore its protective mechanism, mice were divided into control, As and taurine protection groups. Mice of As exposure group exposed to drinking water containing 4 ppm As2O3. Mice of taurine protective group received both 4 ppm As2O3 and 150 mg taurine per kilogram. Mice of control group only drank double-distilled water. All animals were treated for 60 days. Morphology of brain was observed by HE staining. Morris water maze (MWM) tests and step-down passive avoidance task were performed to examine cognition function. Moreover, expressions of some genes and proteins related to regulation learning and memory in brain were tested by Real Time RT-PCR and Western Blot. As a result, abnormal morphologic changes in brain tissue and poor performance in cognition functions were observed in As-exposed mice. The expression of TR beta protein, a regulator of CaMK IV gene, significantly decreased in brains of As-exposed mice than in controls. By contrast, impairment in learning and memory, change in brain morphology and disturbance in protein expression were significantly mitigated in mice of taurine protective group. Our results suggest that taurine supplementation protects against neurotoxicity induced by As in mice.