The anti-inflammatory properties of marine microalgae in LPS-induced macrophages

Inflammatory diseases such as inflammatory bowel disease (IBD) have become one of the leading causes of health issues throughout the world. Existing treatments for IBD are not effective and emphasize the need for a new biologic approach. Inflammation is mediated by cytokines produced by stimulated immune cells such as macrophages. Targeting pro-inflammatory cytokines such as Tumor necrosis factor-a (TNFa) often reduces the disease processes by influencing immune cells. Marine microalgae have been identified as an underexplored reservoir of unique anti-inflammatory compounds. With further investigation, microalgae anti-inflammatory phytochemicals have the potential to be used as therapeutics with profound anti-inflammatory activity with reduced side effects. In this study, anti-inflammatory potential of microalga was assessed in lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophages. Extraction were prepared using solid-liquid of ethyl acetate or Ethanol:H2O (70:30%). We have found that the ethyl acetate extract was the most effective in reducing inflammation. From this extract, we isolated and identified the active fraction using a series of chromatographic steps and analytical methods. Our results showed that pretreatment of RAW 264.7 cells with the crude extract from microalgae significantly inhibited the secretion of TNFa by 50-60% (p < 0.001). Furthermore, the fractions effectively inhibited the LPS-induced TNFa similar to the effect obtained by the crude extract. Interestedly, some fraction contained omega 3 and omega 7 that are known to have anti-inflammatory properties. Our findings suggest, that the microalgae might become a natural source for new anti-inflammatory treatment and lead to a promising route of treatment for chronic inflammation-linked diseases.