title: The polyphenol (-)-epigallocatechin-3-gallate prevents apoA-IIowa amyloidosis in vitro and protects human embryonic kidney 293 cells against amyloid cytotoxicity.
abstract: BACKGROUND
  Apolipoprotein A-I (apoA-I) amyloidosis is either a non-hereditary form with deposits of wild-type apoA-I proteins in atherosclerotic plaques or a hereditary form with progressive accumulation of mutant apoA-I proteins in different tissues. Several small polyphenolic molecules reportedly inhibited formation of fibrillar assemblies of some amyloidogenic proteins and their cytotoxicity, but small molecules that inhibit apoA-I fibril formation have never been reported.
  
  
  METHODS
  Our methods included a thioflavin-T-binding assay, atomic force microscopy and dot blot and cell-based assays.
  
  
  RESULTS
  We showed that (-)-epigallocatechin-3-gallate (EGCG), a tea-derived flavanol, inhibited in vitro fibril formation and disaggregated fibrils preformed by the N-terminal 1-83 fragments of wild-type (WT) apoA-I and the G26R point mutation of apoA-I (apoA-IIowa). We eliminated a common structure recognized by the anti-amyloid antibody OC by incubating apoA-IIowa with EGCG or treating apoA-IIowa fibrils with EGCG, which supported the above observation. In addition, EGCG rescued human embryonic kidney 293 cells from cytotoxicity and attenuated production of reactive oxygen species, which were induced by apoA-IIowa fibrils.
  
  
  CONCLUSIONS
  Our results support the concept that EGCG inhibits amyloid fibril formation of various amyloidogenic proteins. Thus, EGCG may be a candidate for providing a structure to develop de novo inhibitors for amyloidosis treatment.
authors.affiliation: a Department of Molecular Pathology , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .|b Department of Molecular Physical Pharmaceutics , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakajima
authors.affiliation: a Department of Molecular Pathology , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .
authors.forename: Kazuchika
authors.initials: K
authors.lastname: Nishitsuji
authors.affiliation: c Department of Medicinal Chemistry , Kyoto Pharmaceutical University , Yamashina-ku, Kyoto , Japan .
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kawashima
authors.affiliation: a Department of Molecular Pathology , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .|b Department of Molecular Physical Pharmaceutics , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .
authors.forename: Kaori
authors.initials: K
authors.lastname: Kuwabara
authors.affiliation: b Department of Molecular Physical Pharmaceutics , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .
authors.forename: Shiho
authors.initials: S
authors.lastname: Mikawa
authors.affiliation: d Department of Biochemistry , Nagoya University Graduate School of Medicine , Showa-ku, Nagoya , Japan .
authors.forename: Kenji
authors.initials: K
authors.lastname: Uchimura
authors.affiliation: c Department of Medicinal Chemistry , Kyoto Pharmaceutical University , Yamashina-ku, Kyoto , Japan .
authors.forename: Kenichi
authors.initials: K
authors.lastname: Akaji
authors.affiliation: e Department of Pharmacognosy , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan , and.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Kashiwada
authors.affiliation: f Department of Bioanalytical Chemistry , Kobe Pharmaceutical University , Higashinada-ku, Kobe , Japan.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Kobayashi
authors.affiliation: b Department of Molecular Physical Pharmaceutics , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Saito
authors.affiliation: a Department of Molecular Pathology , Institute of Biomedical Sciences, Tokushima University Graduate School , Tokushima , Japan .
authors.forename: Naomi
authors.initials: N
authors.lastname: Sakashita
mesh_terms: D000682:Amyloid / Q000378:metabolism*; D000686:Amyloidosis / Q000517:prevention & control*; D016632:Apolipoprotein A-I / Q000378:metabolism*; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D004353:Drug Evaluation, Preclinical; D057809:HEK293 Cells; D006801:Humans; D066263:Protein Aggregation, Pathological / Q000517:prevention & control; D017433:Protein Structure, Secondary; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: C505693:APOA1 protein, human; D000682:Amyloid; D016632:Apolipoprotein A-I; D017382:Reactive Oxygen Species; D002392:Catechin; C045651:epigallocatechin gallate
keywords: Amyloidosis; EGCG; apolipoprotein A-I; oxidative stress; recombinant amyloidogenic proteins