Amyloid-β inhibits No-cGMP signaling in a CD36- and CD47-dependent manner

PLoS One. 2010 Dec 22;5(12):e15686. doi: 10.1371/journal.pone.0015686.

Abstract

Amyloid-β interacts with two cell surface receptors, CD36 and CD47, through which the matricellular protein thrombospondin-1 inhibits soluble guanylate cyclase activation. Here we examine whether amyloid-β shares this inhibitory activity. Amyloid-β inhibited both drug and nitric oxide-mediated activation of soluble guanylate cyclase in several cell types. Known cGMP-dependent functional responses to nitric oxide in platelets and vascular smooth muscle cells were correspondingly inhibited by amyloid-β. Functional interaction of amyloid-β with the scavenger receptor CD36 was indicated by inhibition of free fatty acid uptake via this receptor. Both soluble oligomer and fibrillar forms of amyloid-β were active. In contrast, amyloid-β did not compete with the known ligand SIRPα for binding to CD47. However, both receptors were necessary for amyloid-β to inhibit cGMP accumulation. These data suggest that amyloid-β interaction with CD36 induces a CD47-dependent signal that inhibits soluble guanylate cyclase activation. Combined with the pleiotropic effects of inhibiting free fatty acid transport via CD36, these data provides a molecular mechanism through which amyloid-β can contribute to the nitric oxide signaling deficiencies associated with Alzheimer's disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyloid beta-Peptides / metabolism*
  • Animals
  • Aorta / cytology
  • CD36 Antigens / biosynthesis
  • CD47 Antigen / biosynthesis
  • Cattle
  • Cyclic GMP / metabolism*
  • Endothelial Cells / cytology
  • Humans
  • Mice
  • Nitric Oxide / metabolism*
  • Protein Conformation
  • Pyrazoles / pharmacology
  • Pyridines / pharmacology
  • Signal Transduction
  • Swine
  • Umbilical Veins / cytology

Substances

  • 3-(4-Amino-5-cyclopropylpyrimidine-2-yl)-1-(2-fluorobenzyl)-1H-pyrazolo(3,4-b)pyridine
  • Amyloid beta-Peptides
  • CD36 Antigens
  • CD47 Antigen
  • Pyrazoles
  • Pyridines
  • Nitric Oxide
  • Cyclic GMP