Modulating the selectivity of matriptase-2 inhibitors with unnatural amino acids

Eur J Med Chem. 2017 Mar 31:129:110-123. doi: 10.1016/j.ejmech.2017.02.006. Epub 2017 Feb 11.

Abstract

Matriptase-2, a type II transmembrane serine protease (TTSP), is expressed in the liver and regulates iron homeostasis via the cleavage of hemojuvelin. Matriptase-2 emerges as an attractive target for the treatment of conditions associated with iron overload, such as hemochromatosis or beta-thalassemia. Starting from the crystal structure of its closest homolog matriptase, we constructed a homology model of matriptase-2 in order to further optimize the selectivity of serine trap peptidomimetic inhibitors for matriptase-2 vs matriptase. Careful modifications of the P4, P3 and P2 positions with the help of unnatural amino acids led to a thorough understanding of Structure-Activity Relationship and a >60-fold increase in selectivity for matriptase-2 vs matriptase. Additionally, the introduction of unnatural amino acids led to significant increases in plasma stability. Such compounds represent useful pharmacological tools to test matriptase-2 inhibition in a context of iron overload.

Keywords: Ketobenzothiazole; Matriptase; Matriptase-2; Peptidomimetics; Selectivity; Serine trap; Slow tight binding inhibitors; Type 2 transmembrane serine proteases.

MeSH terms

  • Amino Acids / chemistry*
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / pharmacology*
  • Homeostasis / drug effects
  • Humans
  • Iron / metabolism
  • Iron Overload / drug therapy*
  • Membrane Proteins / antagonists & inhibitors*
  • Models, Molecular
  • Sensitivity and Specificity
  • Serine Endopeptidases
  • Structure-Activity Relationship

Substances

  • Amino Acids
  • Enzyme Inhibitors
  • Membrane Proteins
  • Iron
  • Serine Endopeptidases
  • matriptase 2