Chemical conjugation of DeltaF508-CFTR corrector deoxyspergualin to transporter human serum albumin enhances its ability to rescue Cl- channel functions

Am J Physiol Lung Cell Mol Physiol. 2008 Aug;295(2):L336-47. doi: 10.1152/ajplung.00059.2008. Epub 2008 May 30.

Abstract

The most common mutation of the cystic fibrosis (CF) gene, the deletion of Phe508, encodes a protein (DeltaF508-CFTR) that fails to fold properly, thus mutated DeltaF508-cystic fibrosis transmembrane conductance regulator (CFTR) is recognized and degraded via the ubiquitin-proteasome endoplasmic reticulum-associated degradation pathway. Chemical and pharmacological chaperones and ligand-induced transport open options for designing specific drugs to control protein (mis)folding or transport. A class of compounds that has been proposed as having potential utility in DeltaF508-CFTR is that which targets the molecular chaperone and proteasome systems. In this study, we have selected deoxyspergualin (DSG) as a reference molecule for this class of compounds and for ease of cross-linking to human serum albumin (HSA) as a protein transporter. Chemical cross-linking of DSG to HSA via a disulfide-based cross-linker and its administration to cells carrying DeltaF508-CFTR resulted in a greater enhancement of DeltaF508-CFTR function than when free DSG was used. Function of the selenium-dependent oxidoreductase system was required to allow intracellular activation of HSA-DSG conjugates. The principle that carrier proteins can deliver pharmacological chaperones to cells leading to correction of defective CFTR functions is therefore proven and warrants further investigations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Cross-Linking Reagents / chemistry
  • Cystic Fibrosis / drug therapy*
  • Cystic Fibrosis / genetics
  • Cystic Fibrosis / metabolism
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics
  • Cystic Fibrosis Transmembrane Conductance Regulator / metabolism*
  • Disulfides / chemistry
  • Drug Carriers / chemistry
  • Drug Carriers / pharmacology*
  • Guanidines / chemistry
  • Guanidines / pharmacology*
  • Humans
  • Immunosuppressive Agents / chemistry
  • Immunosuppressive Agents / pharmacology*
  • Molecular Chaperones / chemistry
  • Molecular Chaperones / pharmacology*
  • Oxidoreductases / metabolism
  • Point Mutation*
  • Protein Folding
  • Serum Albumin / chemistry
  • Serum Albumin / pharmacology*

Substances

  • CFTR protein, human
  • Cross-Linking Reagents
  • Disulfides
  • Drug Carriers
  • Guanidines
  • Immunosuppressive Agents
  • Molecular Chaperones
  • Serum Albumin
  • Cystic Fibrosis Transmembrane Conductance Regulator
  • Oxidoreductases
  • gusperimus