Kinetic analysis of the polymerization and depolymerization of beta(2)-microglobulin-related amyloid fibrils in vitro

Biochim Biophys Acta. 2005 Nov 10;1753(1):34-43. doi: 10.1016/j.bbapap.2005.07.007. Epub 2005 Jul 26.

Abstract

beta(2)-Microglobulin-related (Abeta(2)M) amyloidosis is a serious complication in patients on long-term dialysis, and partial unfolding of beta(2)-microglobulin (beta(2)-m) is believed to be prerequisite to its assembly into Abeta(2)M amyloid fibrils. Many kinds of amyloid-associated molecules (e.g., apolipoprotein E (apoE), glycosaminoglycans (GAGs), proteoglycans (PGs)) may contribute to the development of Abeta(2)M amyloidosis. The formation of Abeta(2)M amyloid fibrils in vitro was first observed at low pH (2.0-3.0). Very recently, low concentrations of 2,2,2-trifluoroethanol (TFE) and the sub-micellar concentration of sodium dodecyl sulfate, a model for anionic phospholipids, have been reported to cause the extension of Abeta(2)M amyloid fibrils at a neutral pH, inducing partial unfolding of beta(2)-m and stabilization of the fibrils. Moreover, apoE, GAGs and PGs were found to stabilize Abeta(2)M amyloid fibrils at a neutral pH, forming a stable complex with the fibrils. Some GAGs, especially heparin enhanced the fibril extension in the presence of TFE at a neutral pH. Some PGs, especially biglycan also induced the polymerization of acid-denatured beta(2)-m. These findings are consistent with the hypothesis that in vivo, specific molecules that affect the conformation and stability of beta(2)-m and amyloid fibrils will have significant effects on the deposition of Abeta(2)M amyloid fibrils.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amyloid / chemistry*
  • Amyloid / drug effects
  • Amyloidosis / metabolism*
  • Animals
  • Apolipoproteins E / pharmacology
  • Glycosaminoglycans / pharmacology
  • Humans
  • Hydrogen-Ion Concentration
  • Kinetics
  • Mice
  • Protein Structure, Quaternary*
  • Proteoglycans / pharmacology
  • Sodium Dodecyl Sulfate / pharmacology
  • Trifluoroethanol / pharmacology
  • beta 2-Microglobulin / chemistry*

Substances

  • Amyloid
  • Apolipoproteins E
  • Glycosaminoglycans
  • Proteoglycans
  • beta 2-Microglobulin
  • Sodium Dodecyl Sulfate
  • Trifluoroethanol