Enhanced memory in Wistar rats by virgin coconut oil is associated with increased antioxidative, cholinergic activities and reduced oxidative stress

Abstract

Context: Virgin coconut oil (VCO) has been reported to possess antioxidative, anti-inflammatory and antistress properties. Objective: Capitalizing on these therapeutic effects, this study investigated for the first time the potential of VCO on memory improvement in vivo. Materials and methods: Thirty male Wistar rats (7-8 weeks old) were randomly assigned to five groups (n=six per group). Treatment groups were administered with 1, 5 and 10 g/kg VCO for 31 days by oral gavages. The cognitive function of treated-rats were assessed using the Morris Water Maze Test. Brains were removed, homogenized and subjected to biochemical analyses of acetylcholine (ACh) and acetylcholinesterase (AChE), antioxidants [superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx) and glutathione reductase (GRx)], lipid peroxidase [malondialdehyde (MDA)] as well as nitric oxide (NO). α-Tocopherol (αT; 150mg/kg) was also included for comparison purposes. Results: VCO-fed Wistar rats exhibited significant (p<0.05) improvement of cognitive functions [reduced escape latency (≥1.8 s), reduced escape distance (≥0.3 m) and increased total time spent on platform (≥1 s)]. The findings were accompanied by elevation of ACh (15%), SOD (8%), CAT (≥54%), GSH (≥20%) and GPx (≥12%) and reduction of AChE (≥17%), MDA (>33%) and NO (≥34%). Overall, memory improvement by VCO was comparable to αT. Discussion and conclusion: VCO has the potential to be used as a memory enhancer, the effect of which was mediated, at least in part, through enhanced cholinergic activity, increased antioxidants level and reduced oxidative stress.