Wang W. et al. (2021) conducted experiments in both in vivo and in vitro formats and showed that in vitro, C004019 significantly increased the level of ubiquitination of Tau in both HEK293-hTau cells and SH-SY5Y cells, and that this increase was eliminated by the proteasome inhibitor MG132. In vivo experiments, by perfusing C004019 into the intracerebroventricular compartment of 3xTg-AD mice, it was found that C004019 was able to reduce the levels of total Tau and phosphorylated Tau in the hippocampus and cortex, and improve the cognitive and synaptic functions of the mice. This evidence concerns the gene MAPT and Alzheimer disease.