Effects of Schisandra chinensis Baillon (Schizandraceae) on lipopolysaccharide induced lung inflammation in mice

Ethnopharmacological relevance: Schisandra chinensis Baillon (Sc), an anti-inflammatory herb that has been used in traditional Chinese medicine for thousands of years, is frequently used to treat upper respiratory tract infections. Aim of the study: This study was conducted to evaluate the ability of a water extract of Sc to prevent airway inflammation both in vitro and in vivo. Materials and methods: Human lung alveolar epithelial-derived A549 cells were stimulated with to interleukin-1 beta, tumor necrosis factor-alpha, and interferon-gamma (IL-1 beta, TNF-alpha, and INF-gamma; cytokine mixture; CM) and treated with Sc extracts. They were then evaluated using nitric oxide (NO), IL-8 and monocyte chemotactic protein-1 (MCP-1) secretions. In the in vivo study, BALB/c mice were challenged with lipopolysaccharide (LPS) to induce acute airway inflammation. After this challenge, the mice were treated with Sc extracts (10, 50 and 100 mg/kg) by oral administration, and inflammatory cells in the bronchoalveolar lavage (BAL) fluid were counted. IL-6 and TNF-alpha secretions were measured using an enzyme-linked immunosorbent assay. Lung tissues of the LPS treated mice were prepared and stained with hematoxylin and eosin (HE) for histological examination. Results: In the A549 cells, Sc extracts dose-dependently and significantly inhibited CM-induced NO production and reduced IL-8 and MCP-1 secretions. Sc extracts efficiently suppressed neutrophil and macrophage infiltrations of lung tissues and increased IL-6 and TNF-a levels in BAL fluid in LPS-instilled BALB/c mice. In addition, Sc extracts treatment inhibited pathologic progress in the lung tissues, as confirmed by H&E staining. These findings indicate that Sc extracts could be potentially useful for the treatment of acute lung inflammation and acute lung injury. (C) 2012 Elsevier Ireland Ltd. All rights reserved.