Anxiogenic, memory-impairing, pro-oxidant and pro-inflammatory effects of sodium benzoate in the mouse brain

Objective: Sodium benzoate (NaB), a commonly used food additive, is effective in preventing deterioration and/or spoilage of foods and drinks. While there have been reports suggesting its potential use as an adjunct in schizophrenia management; there is a lack of information on its effects on the brain, especially when added to dry foods. This study examined the effects of NaB added to rodent feed on neurobehavior, antioxidant status, anti-inflammatory and apoptotic markers in mouse brain. Method: Animals were divided into 4 groups of 10 mice each. Groups included normal control (fed with rodent chow) and 3 groups fed with NaB at 125, 250 and 500 mg/kg, respectively, for eight weeks. Open field, elevated plus maze (EPM), Y-maze, and radial-arm maze behaviors were assessed on day 57, following animals were euthanized 24 hours after the behavioral test. Whole-brain homogenate processed for the assessment of antioxidant status, inflammatory/apoptotic markers, and acetylcholinesterase activity. Results: The NaB diet altered body weight, open-field behaviors, working-memory, and anxiety indices. Brain antioxidant status, tumor necrosis factor-alpha and interleukin-10 decreased, while the malondialdehyde, caspase-3 level, and acetylcholinesterase activity increased. Conclusion: The results of this study revealed that the addition of NaB at these concentrations to rodent chow was associated with memory loss, anxiety, oxidative stress and increased inflammatory/apoptotic effects suggesting vigilance in its use.