AOAH and Alzheimer disease: After the blood carrying LPS was injected into the liver through the portal vein, it was phagocytosed and detoxified by the Kupffer cells, but the hepatic Kupffer cells of the AD mice were in an inhibited state and the hydrolase AOAH of the LPS was significantly decreased, and thus, this led to more LPS leaving the liver and circulating in the animals’ bodies, which eventually led to severe accumulations of LPS in the brains of the AD mice.