Neurotrophic factors are polypeptides that promote the well-being of nerve cells, but their clinical use for, say, sustaining memory is limited because the compounds have trouble getting past the blood-brain barrier. Pamela Maher of the Salk Institute for Biological Studies in La Jolla, Calif., and colleagues have now identified the flavonoid fisetin (shown) as a small molecule that has several properties of a neurotrophic factor and can be taken orally (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.0607822103). The researchers report that fisetin, which is found in strawberries and other foods, enhances memory in mice by increasing activation of the transcription factor CREB (cAMP response element-binding protein), which is involved in the physical changes in the brain underlying the development of long-term memory. Chowing down on strawberries isn't a feasible memory-enhancing regimen, Maher warns, since a person would have to eat 10 lb of the fruit per day to obtain a beneficial effect.