AHR and experimental autoimmune encephalomyelitis: In experimental autoimmune encephalomyelitis (EAE), a common mouse model of Ms, gut metabolites derived from dietary tryptophan (Trp) were shown to activate astrocytic aryl hydrocarbon receptor (AHR) signaling, which limits NF-κB signaling and suppresses CNS inflammation (Rothhammer et al., 2016).