title: Anti-inflammatory activity and mechanism of surfactin in lipopolysaccharide-activated macrophages.
abstract: Surfactin is primarily produced by Bacillus natto TK-1 and is one of the most powerful biosurfactants. It consists of a heptapeptide interlinked with a β-hydroxy fatty acid. Because of its special structure, surfactin shows broad biological effects, including anti-tumour, anti-microbial and anti-mycoplasma activities. It also has potential anti-inflammatory activity; however, the anti-inflammatory mechanism of surfactin has not been explored. In this study, we investigated the anti-inflammatory mechanism of surfactin in lipopolysaccharide (LPS)-stimulated macrophages. Surfactin exhibited an anti-inflammatory effect without cytotoxicity at certain concentrations, and the lipopolysaccharide (LPS)-stimulated cells appeared normal after surfactin treatment. Surfactin significantly inhibited the increased expression of IFN-γ, IL-6, iNOS and nitric oxide (NO). TLR4 is the critical receptor for LPS; therefore, the TLR4 signal transduction pathway is the primary pathway that mediates LPS-induced inflammation. The results show that surfactin downregulated the LPS-induced TLR4 protein expression of macrophages and indicated that the surfactin-mediated signal pathway was involved in with TLR4. The subsequent studies demonstrated that surfactin exhibited anti-inflammatory effects by attenuating the activation of nuclear factor-κB (NF-κB), which is involved in the nuclear factor-κB (NF-κB) cell signalling pathways. These results suggest that surfactin may be a new therapeutic agent for inflammation.
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, No.29, 13th Avenue, Tianjin Economy Technological Development Area, Tianjin, 300457, People's Republic of China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chuan
authors.initials: C
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Dong
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Ma
authors.forename: Lihua
authors.initials: L
authors.lastname: Hou
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Cao
authors.forename: Chunling
authors.initials: C
authors.lastname: Wang
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D018836:Inflammation Mediators / Q000037:antagonists & inhibitors / Q000378:metabolism; D055666:Lipopeptides / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000633:toxicity*; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism*; D051379:Mice; D010456:Peptides, Cyclic / Q000494:pharmacology*
chemical_list: D000893:Anti-Inflammatory Agents; D018836:Inflammation Mediators; D055666:Lipopeptides; D008070:Lipopolysaccharides; D010456:Peptides, Cyclic; C009365:surfactin peptide