Preclinical studies in AD have shown that astaxanthin supplementation results in the amelioration of memory deficits, reduction in Aβ deposition in the hippocampus and cortex, decreased tau phosphorylation and parvalbumin-positive neuron density in the hippocampus of AD model mice compared to control mice [202,203,204]. The gene discussed is MAPT; the disease is Alzheimer disease.