A new N-acetylgalactosamine containing peptide as a targeting vehicle for mammalian hepatocytes via asialoglycoprotein receptor endocytosis

Curr Drug Deliv. 2004 Apr;1(2):119-27. doi: 10.2174/1567201043479939.

Abstract

Galactoside-containing cluster ligands have high affinity for asialoglycoprotein receptors (ASGP-r), which are found in abundance in mammalian parenchymal liver cells. These ligands may be conjugated with a therapeutic drug to improve the efficiency of delivery to diseased liver cells. This report describes a new synthetic route towards clustering glycopeptides containing N-acetyl-D-galactosamine (GalNAc). The building block Fmoc-alpha-(ah-Ac3GalNAc)-L-glutamate allowed access to the target compound YEEE(alpha-ah-GalNAc)(3), a structural mimic of YEE(ah-GalNAc)(3), via solid phase peptide synthesis (SPPS). Fatty acid, poly-lysine, fluorescein and biotin conjugates further demonstrate the facility of the described method. Using fluorescein labeling and 131I labeling, in vitro and in vivo assays confirmed that YEEE(alpha-ah-GalNAc)(3) possesses both specificity and affinity to the liver, similar to the agent YEE(ah-GalNAc)(3), which targets liver lesions. The synthesis described in this report represents a considerable improvement in synthesizing a ligand for ASGP-r by simplifying both the preparation of the starting material and the procedure for conjugating the galactosidase cluster to drugs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylgalactosamine / chemistry
  • Animals
  • Asialoglycoprotein Receptor / metabolism*
  • Cell Line, Tumor
  • Chemistry, Pharmaceutical
  • Drug Carriers
  • Endocytosis
  • Glycopeptides / chemical synthesis*
  • Glycopeptides / pharmacokinetics*
  • Glycopeptides / pharmacology
  • Hepatocytes / drug effects*
  • Hepatocytes / metabolism
  • Humans
  • Kidney / metabolism
  • Ligands
  • Mice
  • Mice, Inbred BALB C
  • Rats
  • Rats, Inbred F344
  • Tissue Distribution

Substances

  • Asialoglycoprotein Receptor
  • Drug Carriers
  • Glycopeptides
  • Ligands
  • tyrosyl(glutamyl)glutamate tris(N-acetylgalactosamineaminohexylglycoside)amide
  • tyrosyl-(alpha-(N-acetylaminogalactopyranosyloxyhexylamino),gamma-(alpha-(N-acetylaminogalactopyranosyloxyhexylamino),gamma-(alpha-(N-acetylaminogalactopyranosyloxyhexylamino)glutamyl))glutamyl)glutamate
  • Acetylgalactosamine