TNF and Cognitive impairment: In addition, Lactobacillus rhamnosus and Bifidobacterium longum have shown to alleviate cognitive impairment in mice by regulation the IFN-γ/IL-10 and TNF-α/IL-10 rations [52], whereas Lactobacillus plantarum and Bifidobacterium longum have also shown to alleviate cognitive impairment in mice by up-regulating NF-kB-mediated BDNF expression [43].