Tryptophan-galactosylamine conjugates inhibit and disaggregate amyloid fibrils of Aβ42 and hIAPP peptides while reducing their toxicity

Commun Biol. 2020 Sep 2;3(1):484. doi: 10.1038/s42003-020-01216-5.

Abstract

Self-assembly of proteins into amyloid fibrils is a hallmark of various diseases, including Alzheimer's disease (AD) and Type-2 diabetes Mellitus (T2DM). Aggregation of specific peptides, like Aβ42 in AD and hIAPP in T2DM, causes cellular dysfunction resulting in the respective pathology. While these amyloidogenic proteins lack sequence homology, they all contain aromatic amino acids in their hydrophobic core that play a major role in their self-assembly. Targeting these aromatic residues by small molecules may be an attractive approach for inhibiting amyloid aggregation. Here, various biochemical and biophysical techniques revealed that a panel of tryptophan-galactosylamine conjugates significantly inhibit fibril formation of Aβ42 and hIAPP, and disassemble their pre-formed fibrils in a dose-dependent manner. They are also not toxic to mammalian cells and can reduce the cytotoxicity induced by Aβ42 and hIAPP aggregates. These tryptophan-galactosylamine conjugates can therefore serve as a scaffold for the development of therapeutics towards AD and T2DM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Amyloid / metabolism*
  • Amyloid / ultrastructure
  • Amyloid beta-Peptides / chemistry
  • Amyloid beta-Peptides / toxicity*
  • Amyloid beta-Peptides / ultrastructure
  • Cell Death / drug effects
  • Cell Line, Tumor
  • Galactosamine / metabolism*
  • Humans
  • Inhibitory Concentration 50
  • Islet Amyloid Polypeptide / chemistry
  • Islet Amyloid Polypeptide / toxicity*
  • Islet Amyloid Polypeptide / ultrastructure
  • Peptide Fragments / chemistry
  • Peptide Fragments / toxicity*
  • Peptide Fragments / ultrastructure
  • Protein Aggregates* / drug effects
  • Tryptophan / metabolism*

Substances

  • Amyloid
  • Amyloid beta-Peptides
  • Islet Amyloid Polypeptide
  • Peptide Fragments
  • Protein Aggregates
  • amyloid beta-protein (1-42)
  • Galactosamine
  • Tryptophan