Mucin-5AC (MUC5AC) (MUC5AC)

Mucin-5AC (MUC5AC) is a high-molecular-weight, gel-forming glycoprotein that serves as a primary structural component of the protective mucus layer in the respiratory and gastrointestinal tracts [7, 11]. In the airways, it is predominantly synthesized and secreted by surface goblet cells to facilitate the trapping and clearance of pathogens and environmental particulates [2, 11]. Pathological overproduction of MUC5AC is a hallmark of chronic inflammatory airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD), where it leads to mucus plugging and airway obstruction [7, 12]. This hypersecretion is driven by various inflammatory kinase pathways, including the epidermal growth factor receptor (EGFR), mitogen-activated protein kinase (MAPK), and phosphoinositide 3-kinase (PI3K) cascades [4, 10]. Therapeutic interventions aim to modulate these signaling pathways or inhibit downstream transcription factors like NF-κB and STAT6 to reduce MUC5AC expression [2, 9]. While targeting MUC5AC production offers a way to alleviate symptoms of muco-obstructive diseases, complete suppression may compromise the innate immune defense of the mucosal barrier [11].

Other names

MUC5MUC-5ACMajor airway mucinOligomeric mucus/gel-forming mucinMucin 5, subtype AC, tracheobronchial

Inhibition of MUC5AC gene transcription and protein synthesis by blocking upstream inflammatory signaling (e.g., EGFR, MAPK, PI3K/Akt) or downstream transcription factors (e.g., NF-κB, STAT6, SPDEF); direct reduction of mucus viscosity via mucolytic agents that cleave disulfide bonds [2, 4, 7, 11].