Reversible effects of vitamins C and E combination on cognitive deficits and oxidative stress in the hippocampus of melamine-exposed rats

• Effect of vitamin C and E on neurotoxic melamine was investigated in Wistar rats.
• We used MWM test, histological stain, and ELISA methods.
• Combined vitamins rescued spatial learning and memory defects.
• Complex vitamins alleviated cell death via inhibiting oxidative stress and apoptosis.
• Mechanisms may be lay in antioxidative effects of combined vitamins.

Previous studies showed that the spatial cognitive deficits of rats were induced by chronic melamine exposure, which was associated with the hippocampal oxidative damage. Currently, we examined the antioxidative effect of vitamins C and E combination on cognitive function in melamine-treated rats. Melamine was oral administrated to male adolescent Wistar at a dosage of 300 mg/kg/day for 28 days. After that, animals received vitamins C and E at a dose of 150 and 200 mg/kg, respectively, intraperitoneally for the next 7 days. Cognitive behaviors were investigated using the Morris water maze test. The biochemical indexes were detected in the hippocampal homogenate. The treatment with vitamin complex significantly ameliorated cognitive deficits induced by melamine. ROS, MDA, and NO contents were almost back to normal, while SOD, CAT, GSH-Px, and NOS activities were improved as well. The neural apoptosis in the hippocampus were ameliorated by regulating the expression of anti-apoptotic protein (Bcl-2) and caspase-3. Additionally, histological observation showed that vitamin complex effectively alleviated the injuries of hippocampal neurons. These results suggest that the potential therapeutic for oxidative damage induced neuronal apoptosis after treatment of vitamins C and E combination, which is most likely related to the antioxidative effects.