RXRA and Alzheimer disease: In different AD mouse models, bexarotene increased Abca1 mRNA and ABCA1 protein levels, but also reduced cerebral load of Aβ and hyperphosphorylated protein tau, which is also a histological marker in AD and other dementias.297,383 This prospect led to synthetic bexarotene derivatives, specifically Z10 and Z36.380 Both candidates induced ABCA1 protein expression by RXR-α activation and reduced Aβ burden in the hippocampus of female APP/PS1 mice.