Effects of sub‐chronic oral caffeine consumption on memory and the hippocampal Akt, GSK‐3β and ERK in mice

Abstract

AbstractBackgroundCaffeine, one of the most widely consumed psychoactive substance in the world, has been shown to affect mood, memory, alertness, and cognitive performance. However, the literature about the effects of caffeine intake on memory is equivocal. This study aimed to assess the effect of sub‐chronic oral gavage of caffeine on memory and the phosphorylation levels of hippocampal Akt (protein kinase B), GSK‐3β (Glycogen Synthase Kinase‐3beta) and ERK (extracellular signal‐regulated kinase) in mice.MethodAdult male NMRI mice were administered with sub‐chronic caffeine at the doses of 0.25, 0.5, 0.75 and 1.5 mg/kg/oral gavage for 10 days before training which continued until the retention day of passive avoidance task. Upon completion of the behavioral assessments, the hippocampi were isolated for western blot analysis to detect the phosphorylated and total levels of Akt, GSK‐3β and ERK proteins.ResultThe results showed that sub‐chronic caffeine ingestion at the dose of 0.5 mg/kg improves memory in mice. Furthermore, the memory enhancing dose of caffeine (0.5 mg/kg) elevated the phosphorylated to total ratios of hippocampal Akt, GSK‐3β and ERK.ConclusionThis study suggests that sub‐chronic low dose of caffeine improves memory and increases the phosphorylation of hippocampal Akt, GSK‐3β and ERK proteins.