Design, Structural Optimization, and Characterization of the First Selective Macrocyclic Neurotensin Receptor Type 2 Non-opioid Analgesic

J Med Chem. 2021 Feb 25;64(4):2110-2124. doi: 10.1021/acs.jmedchem.0c01726. Epub 2021 Feb 4.

Abstract

Neurotensin (NT) receptor type 2 (NTS2) represents an attractive target for the development of new NT-based analgesics. Here, we report the synthesis and functional in vivo characterization of the first constrained NTS2-selective macrocyclic NT analog. While most chemical optimization studies rely on the NT(8-13) fragment, we focused on NT(7-12) as a scaffold to design NTS2-selective macrocyclic peptides. Replacement of Ile12 by Leu, and Pro7/Pro10 by allylglycine residues followed by cyclization via ring-closing metathesis led to macrocycle 4, which exhibits good affinity for NTS2 (50 nM), high selectivity over NTS1 (>100 μM), and improved stability compared to NT(8-13). In vivo profiling in rats reveals that macrocycle 4 produces potent analgesia in three distinct rodent pain models, without causing the undesired effects associated with NTS1 activation. We further provide evidence of its non-opioid antinociceptive activity, therefore highlighting the strong therapeutic potential of NTS2-selective analogs for the management of acute and chronic pain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analgesics / chemical synthesis
  • Analgesics / therapeutic use*
  • Animals
  • Drug Design
  • Male
  • Molecular Structure
  • Neurotensin / analogs & derivatives*
  • Neurotensin / therapeutic use*
  • Pain / drug therapy*
  • Peptide Fragments / chemical synthesis
  • Peptide Fragments / therapeutic use
  • Peptides, Cyclic / chemical synthesis
  • Peptides, Cyclic / therapeutic use*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Neurotensin / metabolism*
  • Structure-Activity Relationship

Substances

  • Analgesics
  • Ntsr2 protein, rat
  • Peptide Fragments
  • Peptides, Cyclic
  • Receptors, Neurotensin
  • Neurotensin

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