Of note is the RXR agonist bexarotene that has been shown to upregulate ABCA1 and ABCG1 thereby increasing apoE4 lipidation, which reverses apoE4-induced cognitive and neuronal impairments in non-amyloid mice [48], and lowers Aβ oligomers and strengthens synaptic viability in E4FAD AD mice [49]. This evidence concerns the gene ABCA1 and Alzheimer disease.