title: Effect of synthesized constituents in the L-tryptophan product on the differentiation of eosinophils and the induction of IL-6: a possible cause of eosinophilia-myalgia syndrome.
abstract: While the pathogenesis of eosinophilia-myalgia syndrome (EMS) remains obscure, the ingestion of L-trypophan (LT) and possibly certain constituents in the LT product might be associated. We investigated the effect of chemically synthesized substances, 1,1'-ethylidene bis[tryptophan] (EBT) and its decomposition product, 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (MTCA) recently identified in the implicated LT, on the eosinophil differentiation and the induction of IL-1 and IL-6. EBT and MTCA alone did not support colony formation. However, EBT or MTCA in conjunction with IL-2 induced colony-forming activity containing a small number of eosinophils. In addition, these LT constituents induced a significant level of IL-6 but not IL-1 beta in the mononuclear cells from normal volunteers and a patient with hypereosinophilic syndrome. These results suggest that certain constituents of LT product are associated with the pathogenesis of EMS through the induction of colony-stimulating factors and IL-6, hence giving rise to eosinophilia and inflammation.
authors.affiliation: Department of Medical Biology and Parasitology, Jichi Medical School, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: J
authors.initials: J
authors.lastname: Tsunoda
authors.forename: T
authors.initials: T
authors.lastname: Suda
authors.forename: Y
authors.initials: Y
authors.lastname: Miura
authors.forename: K
authors.initials: K
authors.lastname: Shioiri-Nakano
authors.forename: T
authors.initials: T
authors.lastname: Kasahara
mesh_terms: D001853:Bone Marrow / Q000473:pathology; D001854:Bone Marrow Cells; D002243:Carbolines / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects*; D004487:Edema / Q000209:etiology; D004802:Eosinophilia / Q000209:etiology*; D004804:Eosinophils / Q000166:cytology* / Q000187:drug effects / Q000473:pathology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects / Q000473:pathology; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis; D007376:Interleukin-2 / Q000494:pharmacology; D015850:Interleukin-6 / Q000096:biosynthesis*; D009135:Muscular Diseases / Q000209:etiology; D012016:Reference Values; D013577:Syndrome; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000633:toxicity*
chemical_list: D002243:Carbolines; D007375:Interleukin-1; D007376:Interleukin-2; D015850:Interleukin-6; C070372:1,1'-ethylidene bis(tryptophan); C038114:1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid; D014364:Tryptophan