New endogenous PPARα ligands have been isolated in hippocampal neurons [38], and one of these ligands, hexadecanamide, upregulates BDNF expression in hippocampal neurons, thus promoting synaptic functions and plasticity, as reported in a mouse model of Alzheimer’s disease (AD), the 5XFAD mouse [39]. The gene discussed is BDNF; the disease is Alzheimer disease.