Abstract: Purpose: The anti-inflammatory activity of astaxanthin docosahexaenoic acid (DHA) monoester was investigated in lipopolysaccharide (LPS)-induced mouse microglial BV2 cells and zebrafish. Methods: Cell morphology was observed by light microscope, cell activity was detected by methyl thiazolyl tetrazolium assay, and nitric oxide (NO) level was determined by Griess method. Zebrafish embryos were microinjected with astaxanthin, and embryo development was observed under a stereomicroscope. The contents of reactive oxygen species (ROS) and malondialdehyde (MDA) were detected with commercial kits. The expression levels of inflammatory factors were determined by real-time fluorescence quantitative polymerase chain reaction. Results: After astaxanthin DHA monomer intervention, the expression level of intracellular inflammatory factors decreased significantly compared with the model group, approaching that in the blank control group. Both free astaxanthin and astaxanthin DHA monomer could protect the development of zebrafish embryos, lower the incidence of embryo malformations induced by LPS, effectively inhibit ROS production in zebrafish with inflammation, significantly reduce the content of MDA, and down-regulate the expression levels of inflammatory factors, and the effect of astaxanthin DHA monomer was more pronounced. Conclusion: Astaxanthin DHA monoester has a stronger anti-inflammatory activity, and a more significant protective effect against LPS-induced inflammation than free astaxanthin.

Key words: astaxanthin DHA monoester; zebrafish; inflammation; microglia; lipopolysaccharide