Esculetin
Esculetin is an active ingredient extracted mainly from the bark of Fraxinus rhynchophylla. Esculetin inhibits platelet-derived growth factor (PDGF)-induced airway smooth muscle cells (ASMCs) phenotype switching through inhibition of PI3K/Akt pathway. Esculetin has antioxidant, antiinflammatory, and antitumor activities[1].