Concentration-dependent Effects of Dietary L-Ascorbic Acid Fortification in the Brains of Healthy Mice

Abstract

Ascorbic acid (AA) is a water-soluble vitamin that is concentrated in the brain in large quantities. There have been reports that it is essential for proper brain functioning. However, there is insufficient information on the possible effects of dietary fortification with AA on the health of the brain. This study examined the effects of dietary fortification of rodent chow with AA on neurobehaviour, antioxidant status, lipid peroxidation, and inflammatory/apoptotic markers in the brain of healthy mice. Mice were randomly assigned into four groups of ten animals each. Groups were normal control [fed rodent chow], and three groups were fed AA-fortified chow at 100, 200, and 300 mg/kg of feed, respectively, for eight weeks. Behavioural tests {Open field, Y-maze, radial-arm maze, and elevated plus maze (EPM)} were carried out on day 57. Twenty-four hours after the last behavioural test, animals were euthanised, and the brains were excised and homogenised for assessment of brain acetylcholinesterase activity, lipid peroxidation, antioxidant status, inflammatory and apoptotic markers. Ascorbic acid fortified diet was associated with concentration-dependent changes in body weight, open-field behaviours, working-memory, and anxiety indices. Also, brain levels of malondialdehyde, caspase-3, and TNF-α decreased, while superoxide dismutase activity, total antioxidant capacity, and IL-10 level increased. Dietary AA fortification with concentrations up to 300 mg/kg of feed was associated with sustained improvement in neurobehavioural and biochemical parameters in the brain of healthy mice, reiterating additional health benefits of AA fortification beyond the prevention of nutritional deficiencies.