Correlation between regional oxidative stress markers of the cerebrum and spatial learning in tocotrienol-mediated protection against light-to-moderate doses of ethanol exposure

ABSTRACT

Tocotrienol, a multipotent nutraceutical with antioxidative, anti-inflammatory and neuroprotective properties, could be used to maintain the cognitive functions even in the presence of neurotoxicants. Oral supplementation of two doses of tocotrienol was used during the three doses of ethanol exposure (comparable with low-to-moderate doses of alcohol consumption in human), and learning, retention, and utilisation of navigation performances were evaluated and correlated with the level of oxidative stress markers in cerebral regions. Rats received ethanol exposure for 4 weeks and tocotrienol supplementation for 4 weeks of ethanol exposure and continued for 2 more weeks. The significant decrement in weight gain during the experimentation was observed only in the groups receiving the highest amount of ethanol exposure (0.6 mg/kg body weight). Only the group exposed to ethanol at 0.4 mg/kg bw demonstrated alterations in acquisition time and post-48 h retention time of Morris water maze navigation task. Significant influences of ethanol exposure and tocotrienol supplementation were observed in the probe test using the Morris water maze. The correlation between oxidative stress parameters of cerebral regions and probe test did not provide any significant information; however, indicated that investigated domains of cognition most likely were associated with frontal cortex and temporal cortex functions.