NOS2 and colitis: Ursolic acid inhibits the activation of NF-κB and MAPK signaling pathways in IECs and macrophages, reduces TNF-α, IL-1β, COX-2, and iNOS in TNBS-induced colitis in mice as well as in LPS-stimulated inflammatory cells expression levels and attenuate the inflammatory response (Chun et al., 2014; Jang et al., 2014; Liu et al., 2016).