Role of ERK/MAPK signalling pathway in anti-inflammatory effects of Ecklonia cava in activated human mast cell line-1 cells

The anti-inflammatory effects of Ecklonia cava (EC) and its mechanism of action were examined in phorbol-12 myristate 13-acetate (30 nmol/L) and A23187 (1 μmol/L) (PMACI) stimulated human mast cell line-1 cells. Nitric oxide content, inducible nitric oxide synthase and cyclooxygenase-2 protein expression, pro-inflammatory cytokines including IL-1β, TNF-α, and IL-6 mRNA and protein expressions were determined. In addition, extracellular regulated protein kinases/mitogen-activated protein kinase (ERK/MAPK) activation was examined. EC dose-dependently suppressed inducible nitric oxide synthase and cyclooxygenase-2 protein expression and subsequently it reduces nitric oxide content in PMACI stimulated human mast cell line-1 cells. EC dose-dependently inhibited the mRNA as well as protein expression of TNF-α, IL-1β, and IL-6 in the PMACI stimulated human mast cell line-1 cells without any cytotoxic effect. Furthermore, EC significantly inhibited PMACI induced phosphorylation of ERK1/2 in a dose-dependent manner without affecting the total protein levels. EC exert its anti-inflammatory actions via inhibition of ERK/MAPK signalling pathway, suggesting that EC is a potent and efficacious anti-inflammatory agent for mast cell-mediated inflammatory diseases.