Y. Wang et al. noted that cognitive deficits were further exacerbated in AD mice treated with 27-hydroxycholesterol (27-OHC) and that elevated levels of IL-17 in mouse brain and intestinal plasma were associated with mouse ileocecal lesions, changes in intestinal permeability and microbial composition, and decreased levels of SCFAs such as propionate and butyrate (100). Here, IL17A is linked to Cognitive impairment.