“…The above findings imply that PDE4B is a promising target in IBD since PDE4B activity is closely related to M1 type macrophage infiltration. Triptolide, the main biologically active substance in Tripterygium wilfordii Hook F. (TwHF), was previously demonstrated to possess powerful anti-inflammatory and immunosuppressive properties in many preclinical studies (38,39). Triptolide was found to regulate multiple inflammatory mediators in vitro and in animal models of inflammation and autoimmune diseases such as nephritis, asthma, and arthritis (40)(41)(42).…”