CLDN1 and Cognitive impairment: Therefore, we selected Lactococcus lactis NK209 (Ll), Lactobacillus rhamnosus NK210 (Lr), and Bifidobacterium longum NK219 (Bl), which increased claudin-1 expression in LPS- or TNBS-treated Caco-2 cells, from the fecal bacteria collection of humans and investigated their effects on TNBS-induced leaky gut and cognitive impairment in mice.