We discovered that UA, a triterpenoid compound with a molecular weight of 456.7 kD that is naturally found in fruit peels, herbs, and spices, exhibited profound decreases in total tau (tau5, HT7) and p-Tau (AT8) levels at multiple sites associated with AD in primary neurons instantly transfected with hTau and HEK293 cells with stable expression of WT full-length hTau (termed HEK293-hTau) (P < 0.05; Fig. 7a, Additional file 1: Fig. S24a). This evidence concerns the gene MAPT and Alzheimer disease.