In Vitro Immune-Enhancement and Anti-Inflammatory Effects of Fatty Acids Extracted from the Halocynthia aurantium Gonad on RAW264.7 Macrophages

Fatty acids extracted from the Halocynthia aurantium gonad (HAGF) were shown to be primarily composed of the highest concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) at 41% and 17% of total fatty acids, respectively. In the present study, HAGF were examined for their immunostimulant and anti-inflammatory effects on RAW264.7 macrophage cells. HAGF were found to significantly boost nitric oxide (NO) production and increase the levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), IL-6, and tumor necrosis factor (TNF)-α expression in a dose-dependent manner. Moreover, the phosphorylation of c-Jun N-terminal kinase/stress-activated protein kinase (JNK), extracellular signal-regulated kinase (ERK), p38, and nuclear factor κB (NF-κB) p65 was up-regulated by the stimulation of RAW264.7 cells with HAGF. When lipopolysaccharide (LPS)—stimulated the macrophages, they also exhibited anti-inflammatory activity via decreasing NO production and immune-related gene expression, Cluster of differentiation (CD) 86 expression, and protein levels in the NF-κB and mitogen-activated protein kinases (MAPK) signaling pathways. Overall, these results indicate that HAGF exert immune-modulatory effects in macrophages.