Immune-modulation effect of Halocynthia aurantium tunic lipid on RAW264.7 cells

The current study evaluated the immune-regulatory potential of lipid extract from Halocynthia aurantium tunic on macrophage cells. The results showed that H. aurantium lipid is composed of primarily SFA (68.32%), followed by MUFA and PUFA (17.61% and 14.07%, respectively). Halocynthia aurantium lipid dose-dependently modulated the NO and PGE₂ production in RAW264.7 cells without any LPS stimulation. The lipid effectively up-regulated the cytokine expression, including IL-1β, IL-6, and TNF-α in RAW264.7 cells. The COX-2 expression as a key biomarker for inflammation was also significantly increased. Conversely, H. aurantium lipid down-regulated the expression of inflammatory cytokines in LPS-stimulated RAW264.7 cells. Halocynthia aurantium lipid modulated the phosphorylation of NF-κB p-65, p38, ERK, and JNK, indicating that this lipid activated through NF-κB and MAPK pathways. These results provide insight into the immune-regulatory activities of H. aurantium tunic lipid and suggest that H. aurantium tunic may a potential lipid source for immune-regulatory molecules.