We observed that (Huynh et al., 2021) mice with HF showed obvious increases in intestinal permeability and plasma LPS levels, which were accompanied by elevated expression of TLR4 in the brain and enhanced neuroinflammation (Havakuk et al., 2017) the intestinal barrier protector IAP attenuated neuroinflammation after HF while effectively increasing plasma LPS levels; and (Xie et al., 2019) TLR4-KO mice showed significant improvements in HF-induced neuroinflammation, which were not markedly affected by intestinal barrier inhibitors or protectors. Here, TLR4 is linked to hydrops fetalis.