MUC5AC and Airway obstruction: Among these, IL-1β can trigger PTGS2 to induce MUC5AC mucin expression through ERK or p38 MAPK, exacerbating airway obstruction, whereas TNF-α may induce PTGS2 to produce prostaglandin E2 (PGE2) and other substances, exacerbating airway inflammation [46–48].