Obviously, lower amounts of microglia and astrocyte accumulation around amyloid plaques in the hippocampus and reduced insoluble Aβ plaques in aged APPSWE/PS1DeltaE9 Tg mice of AD model (which overexpress the Swedish mutation of APP KM670/671NL together with PS1 deleted in exon 9) after treatment with an antibiotic cocktail (Minter et al., 2017) were found, which is only circumstantial evidence that antibiotic interfered with microglial activation through reducing the amounts of microglia. This evidence concerns the gene PSEN1 and Alzheimer disease.