Complexation of amyloid fibrils with charged conjugated polymers

Langmuir. 2014 Apr 8;30(13):3775-86. doi: 10.1021/la404739f. Epub 2014 Mar 28.

Abstract

It has been suggested that conjugated charged polymers are amyloid imaging agents and promising therapeutic candidates for neurological disorders. However, very less is known about their efficacy in modulating the amyloid aggregation pathway. Here, we studied the modulation of Parkinson's disease associated α-synuclein (AS) amyloid assembly kinetics using conjugated polyfluorene polymers (PF, cationic; PFS, anionic). We also explored the complexation of these charged polymers with the various AS aggregated species including amyloid fibrils and oligomers using multidisciplinary biophysical techniques. Our data suggests that both polymers irrespective of their different charges in the side chains increase the fibrilization kinetics of AS and also remarkably change the morphology of the resultant amyloid fibrils. Both polymers were incorporated/aligned onto the AS amyloid fibrils as evident from electron microscopy (EM) and atomic force microscopy (AFM), and the resultant complexes were structurally distinct from their pristine form of both polymers and AS supported by FTIR study. Additionally, we observed that the mechanism of interactions between the polymers with different species of AS aggregates were markedly different.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Amyloid / chemistry*
  • Benzothiazoles
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Fluorocarbon Polymers / chemical synthesis
  • Fluorocarbon Polymers / chemistry*
  • Gene Expression
  • Humans
  • Kinetics
  • Microscopy, Atomic Force
  • Molecular Sequence Data
  • Protein Aggregates*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Solutions
  • Spectroscopy, Fourier Transform Infrared
  • Static Electricity
  • Thiazoles
  • alpha-Synuclein / chemistry*
  • alpha-Synuclein / genetics

Substances

  • Amyloid
  • Benzothiazoles
  • Fluorocarbon Polymers
  • Protein Aggregates
  • Recombinant Proteins
  • Solutions
  • Thiazoles
  • alpha-Synuclein
  • thioflavin T