Transthyretin Amyloidosis: Chaperone Concentration Changes and Increased Proteolysis in the Pathway to Disease

PLoS One. 2015 Jul 6;10(7):e0125392. doi: 10.1371/journal.pone.0125392. eCollection 2015.

Abstract

Transthyretin amyloidosis is a conformational pathology characterized by the extracellular formation of amyloid deposits and the progressive impairment of the peripheral nervous system. Point mutations in this tetrameric plasma protein decrease its stability and are linked to disease onset and progression. Since non-mutated transthyretin also forms amyloid in systemic senile amyloidosis and some mutation bearers are asymptomatic throughout their lives, non-genetic factors must also be involved in transthyretin amyloidosis. We discovered, using a differential proteomics approach, that extracellular chaperones such as fibrinogen, clusterin, haptoglobin, alpha-1-anti-trypsin and 2-macroglobulin are overrepresented in transthyretin amyloidosis. Our data shows that a complex network of extracellular chaperones are over represented in human plasma and we speculate that they act synergistically to cope with amyloid prone proteins. Proteostasis may thus be as important as point mutations in transthyretin amyloidosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Amyloid Neuropathies, Familial / blood
  • Amyloid Neuropathies, Familial / metabolism*
  • Blood Proteins / chemistry
  • Case-Control Studies
  • Electrophoresis, Gel, Two-Dimensional
  • Female
  • Humans
  • Molecular Chaperones / metabolism*
  • Molecular Sequence Data
  • Proteolysis
  • Proteomics
  • Sequence Homology, Amino Acid
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

Substances

  • Blood Proteins
  • Molecular Chaperones

Supplementary concepts

  • Amyloidosis, Hereditary, Transthyretin-Related

Grants and funding

Work was supported by grants SFRH/BPD/41037/2007 (R.A.G.) and SFRH/BPD/73779/2010 and IF/00359/2014 (G.C), PEst-OE/QUI/UI0612/2011, PTDC/QUI/123060/2010 and REDE/1501/REM/2005 from the Fundação para a Ciência e a Tecnologia, and also by the 2011 Junior Research grant from the amyloidosis foundation.