title: Molecular pathogenesis of human amyloidosis: Lessons from β2 -microglobulin-related amyloidosis.
abstract: Amyloidosis refers to a group of diseases with amyloid fibrils deposited in various organs and is classified into more than 30 diseases in humans based on the kind of amyloid protein. In order to elucidate the molecular pathogenesis of human amyloidosis, we studied the molecular mechanism of amyloid fibril formation in vitro. We first developed a novel fluorometric method to determine amyloid fibrils in vitro based on the unique characteristics of thioflavin T. We next proposed a nucleation-dependent polymerization model to explain the general mechanism of amyloid fibril formation in vitro. Based on this model, we characterized the biological molecular interactions that promote or inhibit amyloid fibril formation in vitro and developed models of pathological molecular environment for inducing human β2-microglobulin-related amyloidosis in long-term hemodialysis patients. We also proposed a novel and attractive cytotoxic mechanism of β2-microglobulin amyloid fibrils, that is, the disruption of endosomal/lysosomal membranes by endocytosed amyloid fibrils. These findings may be useful to elucidate the molecular pathogenesis of other kinds of human amyloidosis.
authors.affiliation: Department of Pathological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Naiki
authors.affiliation: Department of Pathological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
authors.forename: Tadakazu
authors.initials: T
authors.lastname: Okoshi
authors.affiliation: Department of Pathological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
authors.forename: Daisaku
authors.initials: D
authors.lastname: Ozawa
authors.affiliation: Department of Pathological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
authors.forename: Itaru
authors.initials: I
authors.lastname: Yamaguchi
authors.affiliation: Department of Pathological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hasegawa
mesh_terms: D000682:Amyloid / Q000032:analysis / Q000378:metabolism* / Q000648:ultrastructure; D000686:Amyloidosis / Q000145:classification / Q000378:metabolism / Q000473:pathology*; D052160:Benzothiazoles; D005470:Fluorometry; D006801:Humans; D008958:Models, Molecular; D058105:Polymerization; D013844:Thiazoles; D001613:beta 2-Microglobulin / Q000378:metabolism*
chemical_list: D000682:Amyloid; D052160:Benzothiazoles; D013844:Thiazoles; D001613:beta 2-Microglobulin; C009462:thioflavin T
keywords: amyloid fibril; amyloidosis; cytotoxic mechanism; extracellular chaperone; nucleation-dependent polymerization model; pathological molecular environment; thioflavin T