DW2009 Elevates the Efficacy of Donepezil against Cognitive Impairment in Mice.

C29 and DW2009 (C29-fermented soybean) alleviate cognitive impairment through the modulation of the microbiota-gut-brain axis. Therefore, we examined whether combining donepezil, a well-known acetylcholinesterase inhibitor, with C29 or DW2009 could synergistically alleviate cognitive impairment in mice. Oral administration of donepezil combined with or without C29 (DC) or DW2009 (DD) alleviated lipopolysaccharide (LPS)-induced cognitive impairment-like behaviors more strongly than treatment with each one alone. Their treatments significantly suppressed the NF-κB/Iba1 (activated microglia) population, NF-κB activation, and tumor necrosis factor-α and interleukin-1β expression in the hippocampus, while the brain-derived neurotropic factor (BDNF)/NeuN cell population and BDNF expression increased. Their treatments strongly suppressed LPS-induced colitis. Moreover, they increased the Firmicutes population and decreased the Cyanobacteria population in gut microbiota. Of these, DD most strongly alleviated cognitive impairment, followed by DC. In conclusion, DW2009 may synergistically or additively increase the effect of donepezil against cognitive impairment and colitis by regulating NF-κB-mediated BDNF expression.