title: Interaction of hIAPP with model raft membranes and pancreatic beta-cells: cytotoxicity of hIAPP oligomers.
abstract: Type II diabetes mellitus (T2DM) is associated with beta-cell failure, which correlates with the formation of pancreatic islet amyloid deposits. The human islet amyloid polypeptide (hIAPP) is the major component of islet amyloid and undergoes structural changes followed by self-association and pathological tissue deposition during aggregation in T2DM. There is clear evidence that the aggregation process is accelerated in the presence of particular lipid membranes. Whereas hIAPP aggregation has been extensively studied in homogeneous model membrane systems, especially negatively charged lipid bilayers, information on the interaction of hIAPP with heterogeneous model raft membranes has been missing until now. In the present study, we focus on the principles of aggregation and amyloid formation of hIAPP in the presence of model raft membranes. Time-lapse tapping mode AFM and confocal fluorescence microscopy experiments followed membrane permeabilization and localization of hIAPP in the raft membrane. Together with the ThT and WST-1 assay, the data revealed elevated cytotoxicity of hIAPP oligomers on INS-1E cells.
authors.affiliation: Physical Chemistry I, Biophysical Chemistry, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany. katrin.weise@tu-dortmund.de
authors.forename: Katrin
authors.initials: K
authors.lastname: Weise
authors.forename: Diana
authors.initials: D
authors.lastname: Radovan
authors.forename: Andrea
authors.initials: A
authors.lastname: Gohlke
authors.forename: Norbert
authors.initials: N
authors.lastname: Opitz
authors.forename: Roland
authors.initials: R
authors.lastname: Winter
mesh_terms: D000682:Amyloid / Q000378:metabolism / Q000633:toxicity*; D006801:Humans; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D058228:Islet Amyloid Polypeptide; D007700:Kinetics; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D008954:Models, Biological
chemical_list: D000682:Amyloid; D058228:Islet Amyloid Polypeptide; D008051:Lipid Bilayers