RESUMO
BACKGROUND: It is valuable to find the potential activity of regulating the excessive mucin secretion by the compounds derived from various medicinal plants. We investigated whether aqueous extract of the root bark of Morus alba L. (AMA), kuwanon E, kuwanon G, mulberrofuran G, and morusin significantly affect the secretion and production of airway mucin using in vivo and in vitro experimental models. METHODS: Effect of AMA was examined on hypersecretion of airway mucin in sulfur dioxide-induced acute bronchitis in rats. Confluent NCI-H292 cells were pretreated with ethanolic extract, kuwanon E, kuwanon G, mulberrofuran G, or morusin for 30 minutes and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 hours. The MUC5AC mucin secretion and production were measured by enzyme-linked immunosorbent assay. RESULTS: AMA stimulated the secretion of airway mucin in sulfur dioxide-induced bronchitis rat model; aqueous extract, ethanolic extract, kuwanon E, kuwanon G, mulberrofuran G and morusin inhibited the production of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively. CONCLUSION: These results suggest that extract of the root bark and the natural products derived from Morus alba L. can regulate the secretion and production of airway mucin and, at least in part, explains the folk use of extract of Morus alba L. as mucoregulators in diverse inflammatory pulmonary diseases.
RESUMO
In this study, we investigated whether apigenin and wogonin affect MUC5AC mucin production and gene expression induced by phorbol ester (phorbol 12-myristate 13-acetate, PMA) or epidermal growth factor (EGF) from human airway epithelial cells. Confluent NCI-H292 cells were pretreated with each agent for 30 min and then stimulated with PMA or EGF for 24 h, respectively. MUC5AC mucin gene expression and mucin protein production were measured by reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA). The results were as follows: (i) apigenin and wogonin were found to inhibit the production of MUC5AC mucin protein induced by PMA or EGF; (ii) both compounds also inhibited the expression of MUC5AC mucin gene induced by PMA or EGF. These results suggest that apigenin and wogonin can inhibit mucin gene expression and production of mucin protein, by directly acting on airway epithelial cells.
Assuntos
Apigenina/farmacologia , Células Epiteliais/efeitos dos fármacos , Flavanonas/farmacologia , Mucina-5AC/metabolismo , Linhagem Celular , Fator de Crescimento Epidérmico/farmacologia , Células Epiteliais/metabolismo , Humanos , Mucina-5AC/genética , Ésteres de Forbol/farmacologiaRESUMO
Despite gaps in our knowledge of how phytochemicals interfere with cellular functions, several natural plant products are utilized to prevent or treat a wide range of diseases. Identification of an agent with therapeutic potential requires multiple steps involving in vitro studies, efficacy and toxicity studies in animal models, and then human clinical trials. This review provides a brief introduction on natural products that may help to treat and/or prevent bronchial asthma and describes our current understanding of their molecular mechanisms based on various in vitro, in vivo, and clinical studies. We focus on the anti-inflammatory and anti-vascular actions of the plant products and other roles beyond the anti-oxidative effects.