MUC5AC and chronic obstructive pulmonary disease: Interestingly, S-allylmercapto-l-cysteine (SAMC), one of the bioactive phytochemicals found in aged garlic, improved the LPS-induced mucus secretion of a COPD cell model, the human airway submucosal gland cell line (SPC-A1), up-regulating AQP5 and mucin 5AC (MUC5AC) via NF-κB signaling pathway (Yang et al., 2016).