<i>Foeniculum vulgare</i> Mill. Protects against Lipopolysaccharide-induced Acute Lung Injury in Mice through ERK-dependent NF-kB Activation

<i>Foeniculum vulgare</i> Mill. Protects against Lipopolysaccharide-induced Acute Lung Injury in Mice through ERK-dependent NF-kB Activation

<i>Foeniculum vulgare</i> Mill. (fennel) is used to flavor food, in cosmetics, as an antioxidant, and to treat microbial, diabetic and common inflammation. No study to date, however, has assessed the anti-inflam-matory effects of fennel in experimental models of inflammation. The aims of this study were to investigate the anti-inflammatory effects of fennel in model of lipopolysaccharide (LPS)-induced acute lung injury. Mice were randomly assigned to seven groups (n=7∼10). In five groups, the mice were intraperitoneally injected with 1% Tween 80-saline (vehicle), fennel (125, 250, 500<i>μ</i>l/kg), or dexame-thasone (1 mg/kg), followed 1 h later by intratracheal instillation of LPS (1.5 mg/kg). In two groups, the mice were intraperitoneally injected with vehicle or fennel (250<i>μ</i>l/kg), followed 1 h later by intra-tracheal instillation of sterile saline. Mice were sacrificed 4 h later, and bronchoalveolar lavage fluid (BALF) and lung tissues were obtained. Fennel significantly and dose-dependently reduced LDH activity and immune cell numbers in LPS treated mice. In addition fennel effectively suppressed the LPS-induced increases in the production of the inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha, with 500<i>μ</i>l/kg fennel showing maximal reduction. Fennel also significantly and dose-dependently reduced the activity of the proinflammatory mediator matrix metalloproteinase 9 and the immune modulator nitric oxide (NO). Assessments of the involvement of the MAPK signaling pathway showed that fennel significantly decreased the LPS-induced phosphorylation of ERK. Fennel effectively blocked the inflammatory processes induced by LPS, by regulating pro-inflammatory cytokine production, transcription factors, and NO.