MUC5AC and chronic obstructive pulmonary disease: Furthermore, Song et al. (2016) offered evidence that oral administration of Dendrobium officinale Kimura and Migo [Orchidaceae; Dendrobii caulis] polysaccharides (DOPs) could ameliorate pulmonary dysfunction against cigarette smoke-induced chronic pulmonary inflammatory processes via significantly decreasing the levels of pro-inflammatory mediators (interleukin 6, IL-6, and C-reactive protein, CRP) and remarkably downregulating MUC5AC and upregulating AQP5 in COPD models and patients.