The dietary capsaicin group increased PI3K/AKT and decreased GSK-3β activity, which was also observed in the hippocampus compared with that in T2DM control rats that did not receive capsaicin, indicating that capsaicin inhibited the phosphorylation of tau protein by increasing the PI3K/AKT and inhibiting GSK-3β activity. The gene discussed is GSK3B; the disease is type 2 diabetes mellitus.