Sea lettuce (Ulva fasciata) extract has an inhibitory effect on proinflammatory cytokine production in CpG-stimulated bone marrow-derived macrophages and dendritic cells

Abstract

This report was designed to study inhibitory effect of sea lettuce (Ulva fasciata) extract (UFE) on proinflammatory cytokine production in bone marrow-derived macrophages (BMDM) and dendritic cells (BMDC). The UFE (0–50 μg/mL) pre-treatment showed a dose dependant inhibitory effect on interlukin (IL)-12 p40, IL-6, and tumor necrosis factor (TNF)-α productions in CpG-stimulated BMDMs and BMDCs as compared to non-treated controls. The UFE pre-treatment exhibited strong inhibitory effect on the phosphorylation of p38 mitogen-activated protein kinase (MAPK) while it showed moderate inhibition on nuclear factor (NF)-κB activation as indirectly evaluated by degradation of IκBα. In activator protein (AP)-1 and NF-κB reporter gene assay, the UFE pre-treatment showed moderate inhibitory effect on both AP-1- and NF-κBdependent reporter gene activities. Thus, these results suggest that inhibitory effect of UFE on pro-inflammatory cytokine production may correlate with partial inhibition of both AP-1 and NF-κB pathways. Hence, our data warrant further studies concerning potentials of sea lettuce for medicinal food.