Ethanol extract of Chondracanthus tenellus(Harvey)Hommersand attenuates lipopolysaccharide-induced inflammatory and oxidative response by blocking the NF-κB,MAPKs,and PI3K/Akt signaling pathways

Objective:To investigate whether the ethanol extract of Chondracanthus tenellus(Harvey)Hommersand,a type of red algae,could exhibit anti-inflammatory potential in lipopolysaccharide(LPS)-stimulated macrophages.Methods:The ethanol extract of Chondracanthus tenellus was applied to 100 ng/mL LPS-stimulated RAW 264.7 cells,and cell viability,phagocytic ability,levels of pro-inflammatory factors,and the production of reactive oxygen species were measured.To identify the underlying mechanism of the ethanol extract of Chondracanthus tenellus,the expression of inflammation-regulated genes was estimated.Results:The ethanol extract of Chondracanthus tenellus had no cytotoxic effect at concentrations below 300μg/mL,and reduced the LPS-induced production of inflammatory mediators including nitric oxide(NO)and prostaglandin E2.Furthermore,the extract markedly suppressed the expression of inducible NO synthase and cyclooxygenase-2,as well as the production of reactive oxygen species.The LPS-induced up-regulation of pro-inflammatory cytokines was attenuated by treatment with the ethanol extract of Chondracanthus tenellus,reducing their extracellular secretion.The Chondracanthus tenellus extract also inhibited LPS-mediated activation of nuclear factor-kappa B(NF-κB).In addition,the phosphorylation of mitogen activated protein kinases(MAPKs)and phosphatidylinositol 3 kinase(PI3K)/Akt was markedly increased by LPS,which was significantly abolished by the Chondracanthus tenellus extract.Conclusions:Our findings indicate that the ethanol extract of Chondracanthus tenellus exhibited potential anti-inflammatory and antioxidant effects through downregulating the NF-κB,MAPKs,and PI3K/Akt signaling pathways in LPS stimulated RAW 264.7 macrophages.tenellus extract.Conclusions:Our findings indicate that the ethanol extract of Chondracanthus tenellus exhibited potential anti-inflammatory and antioxidant effects through downregulating the NF-κB,MAPKs,and PI3K/Akt signaling pathways in LPS stimulated RAW 264.7 macrophages.