title: Inhibitory effects of adlay bran (Coix lachryma-jobi L. var. ma-yuen Stapf) on chemical mediator release and cytokine production in rat basophilic leukemia cells.
abstract: BACKGROUND
  Adlay (Job's tears, Coix lachryma-jobi L. var. ma-yuen Stapf) has long been used in China to treat rheumatism.
  
  
  OBJECTIVE
  We investigated the anti-allergic effects of adlay bran on rat basophilic leukemia (RBL)-2H3 cells.
  
  
  METHODS
  To evaluate the anti-allergic effects of adlay bran, the release of histamines and cytokines were measured using ELISA. To explore the mechanism of these effects, the protein expression levels were determined using western blotting.
  
  
  RESULTS
  A 40.8μg/mL concentration of the ethyl acetate fraction of the ethanolic extracts of adlay bran (ABE-EtOAc) effectively inhibited mast cell degranulation. The 40-100% EtOAc/Hex subfractions of ABE-EtOAc inhibited histamine release with an IC(50) of 71-87μg/mL. Moreover, the ABE-EtOAc subfractions suppressed the secretion of interleukin (IL)-4, IL-6 and tumor necrosis factor-α in the RBL-2H3 cells, indicating that adlay bran can inhibit cytokine secretion in the late phase of the allergic reaction. In addition, adlay bran reduced the intracellular production of reactive oxygen species, inhibited the phosphorylation of Akt and decreased the expression of protein kinase C. Furthermore, six phenolic acids and one flavone were isolated. Of these compounds, luteolin showed the most potent inhibitory activity (IC(50)=1.5μg/mL).
  
  
  CONCLUSIONS
  Adlay bran extract reduced the release of histamines and cytokines and suppressed the production of Akt. These combined effects influenced the signal transduction in RBL-2H3 cells, thereby revealing the mechanisms of the anti-allergic effects of adlay.
authors.affiliation: Graduate Institute of Food Science and Technology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.
authors.forename: Hong-Jhang
authors.initials: HJ
authors.lastname: Chen
authors.forename: Yi-Chen
authors.initials: YC
authors.lastname: Lo
authors.forename: Wenchang
authors.initials: W
authors.lastname: Chiang
mesh_terms: D000085:Acetates / Q000737:chemistry; D000818:Animals; D018926:Anti-Allergic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D031742:Coix / Q000737:chemistry; D016207:Cytokines / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D000431:Ethanol / Q000737:chemistry; D006636:Histamine Release / Q000187:drug effects*; D018836:Inflammation Mediators / Q000378:metabolism*; D015847:Interleukin-4 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D015471:Leukemia, Basophilic, Acute / Q000276:immunology*; D047311:Luteolin / Q000302:isolation & purification / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology; D010766:Phosphorylation; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010946:Plants, Medicinal; D011493:Protein Kinase C / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D012639:Seeds; D015398:Signal Transduction / Q000187:drug effects; D012997:Solvents / Q000737:chemistry; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D001619:beta-N-Acetylhexosaminidases / Q000378:metabolism
chemical_list: D000085:Acetates; D018926:Anti-Allergic Agents; D016207:Cytokines; D018836:Inflammation Mediators; D015850:Interleukin-6; D010636:Phenols; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D012997:Solvents; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; D000431:Ethanol; C007650:ethyl acetate; D051057:Proto-Oncogene Proteins c-akt; D011493:Protein Kinase C; D001619:beta-N-Acetylhexosaminidases; D047311:Luteolin