title: Inhibitory effect of phloretin and biochanin A on IgE-mediated allergic responses in rat basophilic leukemia RBL-2H3 cells.
abstract: OBJECTIVE
  Anti-allergic effects and action mechanism of phloretin (Phl) and biochanin A (BioA) on the IgE-antigen complex-mediated allergic responses in rat basophilic leukemia RBL-2H3 cells were investigated.
  
  
  METHODS
  Cell viability, formation of reactive oxygen species (ROS), DPPH radical-scavenging activity, β-hexosaminidase release, production of interleukin (IL)-4, IL-13, and tumor necrosis factor-alpha (TNF-α) and phosphorylation of Akt and mitogen-activated protein kinase (MAPK) were determined by MTT assay, 2,7-dichlorofluorescein diacetate (DCF-DA) assay, DPPH radical-scavenging assay, reverse transcriptase polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and western blot analysis, respectively.
  
  
  RESULTS
  Ph1 and BioA dose-dependently inhibited the formation of ROS and the release of β-hexosaminidase from the RBL-2H3 cells and also showed DPPH radical-scavenging activity. Ph1 and BioA suppressed the antigen-induced phosphorylation of the downstream signaling intermediates, including MAPK and Akt, which are critical for the production of pro-inflammatory cytokines, and also significantly attenuated the production of IgE-mediated pro-inflammatory cytokines, such as IL-4, IL-13, and TNF-α.
  
  
  CONCLUSIONS
  Phloretin and biochanin A attenuate the degranulation and allergic cytokine production through inhibition of intracellular ROS production and the phosphorylation of Akt and the MAPKs, such as ERK1/2, p38, and JNK. The results of this study suggested that these two plant flavonoids may have potent anti-allergic activity in vitro.
authors.affiliation: Department of Food Science and Nutrition, College of Health, Welfare and Education, Gwangju University, Gwangju 503-703, Republic of Korea.
authors.forename: Mi Ja
authors.initials: MJ
authors.lastname: Chung
authors.forename: Jae Kyung
authors.initials: JK
authors.lastname: Sohng
authors.forename: Doo Jin
authors.initials: DJ
authors.lastname: Choi
authors.forename: Yong Il
authors.initials: YI
authors.lastname: Park
mesh_terms: D000818:Animals; D015153:Blotting, Western; D045744:Cell Line, Tumor; D016207:Cytokines / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D016166:Free Radical Scavengers / Q000008:administration & dosage / Q000494:pharmacology; D019833:Genistein / Q000008:administration & dosage / Q000494:pharmacology*; D007073:Immunoglobulin E / Q000276:immunology*; D015471:Leukemia, Basophilic, Acute / Q000276:immunology*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010693:Phloretin / Q000008:administration & dosage / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D016207:Cytokines; D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D007073:Immunoglobulin E; D019833:Genistein; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases; D010693:Phloretin; C004541:biochanin A
keywords: Anti-allergic activity; Cytokine; Degranulation; Flavonoids; RBL-2H3 cells