Information Toddalolactone Toddalolactone, a natural coumarin, inhibits the activity of recombinant human Plasminogen activator inhibitor-1 (PAI-1) in a dose-dependent manner, yielding an IC50 value of 37.31 ± 3.23 μM. Targets PAI-1 37.31 μM In vitro Toddalolactone inhibits the binding between PAI-1 and uPA, and therefore prevented the formation of the PAI-1/uPA complex. In vivo Intraperitoneal injection of toddalolactone in mice significantly prolonged tail bleeding and reduced arterial thrombus weight in a FeCl3-induced thrombosis model. Moreover, the hydroxyproline level in the plasma and the degree of liver fibrosis in mice were decreased after intraperitoneal injection of toddalolactone in CCl4-induced mouse liver fibrosis model.