The mechanism of neurodegeneration caused by β-amyloid (Aβ) in Alzheimer's disease is still controversial. Neuronal toxicity is exerted mostly by various species of soluble Aβ oligomers. Recent data depict membranes as the main sites where proteins/peptides are recruited and concentrated, misfold, and nucleate amyloids; at the same time, membranes are considered key triggers of amyloid toxicity.We demonstrated the capability of Aβ to penetrate and destabilize stacked lipid bilayers in a previous work. In this study, in order to maintain the natural fluidity of the membrane, polymer cushioned lipid bilayers have been used as a model for neuronal membrane. Layer-by-layer technique was used for the fabrication of the polymer cushion of charged poly-electrolytes, the lipid membrane is built on the polymer film by unilamellar vesicle fusion. Neutron reflectivity was used to monitor the kinetics of adsorption of the lipid bilayer onto the polymer surface; the conditions for the best surface coverage have been determined. The structure of the lipid bilayers is modified by the interaction with Aβ1-42; Neutron reflectivity showed a change of the scattering density profile in the direction perpendicular to the membrane plane, suggesting penetration of Aβ in the double layer. Atomic force microscope (AFM) has been used to test the lipid packing of the membrane through film rupture experiments and to compare the bilayer morphology in the presence or in the absence of Aβ. We demonstrated that the presence of Aβ weakens the lipid packing in the model membranes.We compared the results obtained on polymer cushioned lipid bilayers with those obtained using a rigid substrate (freshly cleaved mica) for membrane preparation. The Interaction with β-Amyloid Impairs the Mechanical Stability of Polymer Cushioned Membrane | Request PDF. Available from: https://www.researchgate.net/publication/247278123_The_Interaction_with_b-Amyloid_Impairs_the_Mechanical_Stability_of_Polymer_Cushioned_Membrane [accessed Aug 07 2018].

The interaction with β-amyloid impairs the mechanical stability of polymer cushioned membrane.

CANALE, CLAUDIO;DIASPRO, ALBERTO GIOVANNI
2010-01-01

Abstract

The mechanism of neurodegeneration caused by β-amyloid (Aβ) in Alzheimer's disease is still controversial. Neuronal toxicity is exerted mostly by various species of soluble Aβ oligomers. Recent data depict membranes as the main sites where proteins/peptides are recruited and concentrated, misfold, and nucleate amyloids; at the same time, membranes are considered key triggers of amyloid toxicity.We demonstrated the capability of Aβ to penetrate and destabilize stacked lipid bilayers in a previous work. In this study, in order to maintain the natural fluidity of the membrane, polymer cushioned lipid bilayers have been used as a model for neuronal membrane. Layer-by-layer technique was used for the fabrication of the polymer cushion of charged poly-electrolytes, the lipid membrane is built on the polymer film by unilamellar vesicle fusion. Neutron reflectivity was used to monitor the kinetics of adsorption of the lipid bilayer onto the polymer surface; the conditions for the best surface coverage have been determined. The structure of the lipid bilayers is modified by the interaction with Aβ1-42; Neutron reflectivity showed a change of the scattering density profile in the direction perpendicular to the membrane plane, suggesting penetration of Aβ in the double layer. Atomic force microscope (AFM) has been used to test the lipid packing of the membrane through film rupture experiments and to compare the bilayer morphology in the presence or in the absence of Aβ. We demonstrated that the presence of Aβ weakens the lipid packing in the model membranes.We compared the results obtained on polymer cushioned lipid bilayers with those obtained using a rigid substrate (freshly cleaved mica) for membrane preparation. The Interaction with β-Amyloid Impairs the Mechanical Stability of Polymer Cushioned Membrane | Request PDF. Available from: https://www.researchgate.net/publication/247278123_The_Interaction_with_b-Amyloid_Impairs_the_Mechanical_Stability_of_Polymer_Cushioned_Membrane [accessed Aug 07 2018].
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11567/227318
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 0
social impact