Ethanol Extract of Elaeocarpus petiolatus Inhibits Lipopolysaccharide-Induced Inflammation in Macrophage Cells

Elaeocarpus petiolatus is known to exert active oxygen scavenging, anti-aging, and whitening actions. However, the biological effects of E. petiolatus on inflammation and the underlying mechanisms are yet to be established. In the present study, we investigated the anti-inflammatory effects of the ethanol extract from E. petiolatus (EPE) bark in murine Raw264.7 macrophages stimulated with lipopolysaccharide (LPS). EPE inhibited the production of PGE₂, TNF-α, and IL-1β in a dose-dependent manner in Raw264.7 cells stimulated with LPS. The decrease in PGE₂ production was correlated with reduced COX-2 expression. Furthermore, EPE suppressed the phosphorylation of extracellular signal-related kinases (ERK), c-Jun N-terminal kinase (JNK), and p38 as well as translocation of the NF-κB p65 subunit from the cytosol to nucleus. Our results suggest that EPE exerts anti-inflammatory activity through inhibition of inflammatory mediators, such as PGE₂, TNF-α, and IL-1β, and downregulation of COX-2 via suppression of NF-κB translocation and phosphorylation of ERK, JNK, and p38 in LPS-stimulated Raw264.7 cells.