IDO1 and Alzheimer disease: A study designed to evaluate the neuroprotection effect of coptisine discovered that coptisine (50 mg/kg, oral, once daily for one month; 10 μmol/L, 5 hours) reversed the enhanced IDO activity in AβPPswe/PS1ΔE9 mice, and it as well prevented AD pathogenesis by means of blocking microglia and astrocyte activation through inactivating CD11b and GFAP, respectively.78 In accordance with in vivo study, coptisine (0‐40 μmol/L, 24 hours) diminished IDO overexpression and GUIN overproduction induced by Aβ1‐42 in microglia cells.