Effect of San-ao Decoction, a traditional Chinese prescription, on IL-4 treated normal human bronchial epithelium

Ethnopharmacological relevanceSan-ao Decoction (SA) is a classical prescription, clinically employed to treat asthma in Chinese medicine.Aim of studyThe present study was designed to examine whether SA has a protective effect on normal human bronchial epithelium modeled by interleukin-4 (IL-4), in association with eotaxin-3.Materials and methodsSA is made of three traditional Chinese medicines: Herba Ephedrae, Semen Armeniacae amarum and Radix Glycyrrhizae. Apoptosis was measured by fluorescence microscopy and flow cytometry with IL-4 activated NHBE. In addition, eotaxin-3 mRNA's expression was detected by RT-PCR in NHBE stimulated with IL-4.ResultsFluorescence microscopy and flow cytometry showed that IL-4-induced normal human bronchial epithelium (NHBE) apoptosis, while SA decreased the apoptosis of NHBE with IL-4 stimulation. RT-PCR showed no expression or low expression of eotaxin-3 mRNA on NHBE, IL-4 enhanced the eotaxin-3 mRNA's expression, and that could be decreased by SA.ConclusionsThe results indicate that SA can decrease NHBE's damage and inflammation through reducing eotaxin-3 mRNA expression.

Graphical abstractFluorescence microscope and flow cytometric analysis results showed IL-4 (10 ng/ml) could damage the NHBE, San-ao Decoction (555.55 μg/ml) could protect the damage with IL-4. Blue arrows: apoptotic cell; red arrows: necrotic cell and pink arrow: normal cell. Magnification, 400×.Figure optionsDownload full-size imageDownload as PowerPoint slide