Cognitive impairments can be devastating for quality of life, and thus, preventing or counteracting them is of great value. To this end, the present study exploits the potential of the plantRhodiola roseaand identifies the constituent ferulic acid eicosyl ester [icosyl-(2E)-3-(4-hydroxy-3-methoxyphenyl)-prop-2-enoate (FAE-20)] as a memory enhancer. We show that food supplementation with dried root material fromR. roseadose-dependently improves odor-taste reward associative memory scores in larvalDrosophilaand prevents the age-related decline of this appetitive memory in adult flies. Task-relevant sensorimotor faculties remain unaltered. From a parallel approach, a list of candidate compounds has been derived, includingR. rosea–derived FAE-20. Here, we show that bothR. rosea–derived FAE-20 and synthetic FAE-20 are effective as memory enhancers in larvalDrosophila. Synthetic FAE-20 also partially compensates for age-related memory decline in adult flies, as well as genetically induced early-onset loss of memory function in young flies. Furthermore, it increases excitability in mouse hippocampal CA1 neurons, leads to more stable context-shock aversive associative memory in young adult (3-month-old) mice, and increases memory scores in old (>2-year-old) mice. Given these effects, and given the utility ofR. rosea—the plant from which we discovered FAE-20—as a memory enhancer, these results may hold potential for clinical applications.
Reward enhances memory via age-varying online and offline neural mechanisms across development
