title: The role of peptides derived from Spirulina maxima in downregulation of FcεRI-mediated allergic responses.
abstract: METHODS
  Spirulina has been found suitable for use as a bioactive additive. It is an excellent source of protein that can be hydrolyzed into bioactive peptides. Two peptides LDAVNR (P1) and MMLDF (P2) purified from enzymatic hydrolysate of Spirulina maxima have been reported to be effective against early atherosclerotic responses. In this study, the intracellular mechanism involved in the downregulation of these peptides on high-affinity IgE receptor-mediated allergic reaction was further investigated.
  
  
  RESULTS
  RBL-2H3 mast cells were pretreated with P1 or P2 and sensitized with dinitrophenyl-specific IgE antibody before stimulation of antigen dinitrophenyl-BSA. It was revealed that P1 and P2 exhibited significant inhibition on mast-cell degranulation via decreasing histamine release and intracellular Ca(2+) elevation. The inhibitory activity of P1 was found due to blockade of calcium- and microtubule-dependent signaling pathways. Meanwhile, the inhibition of P2 was involved in suppression of phospholipase Cγ activation and reactive oxygen species production. Moreover, the suppressive effects of P1 and P2 on generation of IL-4 were evidenced via depression of nuclear factor-κB translocation.
  
  
  CONCLUSIONS
  These findings indicate that peptides P1 and P2 from S. maxima may be promising candidates of antiallergic therapeutics, contributing to development of bioactive food ingredients for amelioration of allergic diseases.
authors.affiliation: Marine Bioprocess Research Center, Pukyong National University, Busan, Republic of Korea.
authors.forename: Thanh-Sang
authors.initials: TS
authors.lastname: Vo
authors.forename: Dai-Hung
authors.initials: DH
authors.lastname: Ngo
authors.forename: Kyong-Hwa
authors.initials: KH
authors.lastname: Kang
authors.forename: Sun-Joo
authors.initials: SJ
authors.lastname: Park
authors.forename: Se-Kwon
authors.initials: SK
authors.lastname: Kim
mesh_terms: D000485:Allergens / Q000276:immunology; D000818:Animals; D018926:Anti-Allergic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D015536:Down-Regulation; D006632:Histamine / Q000276:immunology; D006636:Histamine Release / Q000276:immunology; D006967:Hypersensitivity / Q000188:drug therapy; D007073:Immunoglobulin E / Q000276:immunology; D015847:Interleukin-4 / Q000276:immunology; D008407:Mast Cells / Q000187:drug effects / Q000276:immunology; D062105:Molecular Docking Simulation; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology*; D051966:Phospholipase C gamma / Q000037:antagonists & inhibitors / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D017455:Receptors, IgE / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D053545:Spirulina / Q000737:chemistry*
chemical_list: D000485:Allergens; D018926:Anti-Allergic Agents; C553474:FCER1A protein, rat; D016328:NF-kappa B; D010455:Peptides; D017382:Reactive Oxygen Species; D017455:Receptors, IgE; D015847:Interleukin-4; D007073:Immunoglobulin E; D006632:Histamine; D051966:Phospholipase C gamma
keywords: Allergic reaction; FcεRI; Histamine; IL-4; Spirulina maxima