Discovery of a functionally selective ghrelin receptor (GHSR1a) ligand for modulating brain dopamine

Proc Natl Acad Sci U S A. 2022 Mar 8;119(10):e2112397119. doi: 10.1073/pnas.2112397119. Epub 2022 Mar 3.

Abstract

SignificanceThe modulation of growth hormone secretagogue receptor-1a (GHSR1a) signaling is a promising strategy for treating brain conditions of metabolism, aging, and addiction. GHSR1a activation results in pleiotropic physiological outcomes through distinct and pharmacologically separable G protein- and β-arrestin (βarr)-dependent signaling pathways. Thus, pathway-selective modulation can enable improved pharmacotherapeutics that can promote therapeutic efficacy while mitigating side effects. Here, we describe the discovery of a brain-penetrant small molecule, N8279 (NCATS-SM8864), that biases GHSR1a conformations toward Gαq activation and reduces aberrant dopaminergic behavior in mice. N8279 represents a promising chemical scaffold to advance the development of better treatments for GHSR1a-related brain disorders involving the pathological dysregulation of dopamine.

Keywords: GPCR; NCATS-SM8864; dopamine; functional selectivity; ghrelin.

MeSH terms

  • Animals
  • Brain / metabolism*
  • Dopamine / genetics
  • Dopamine / metabolism*
  • GTP-Binding Protein alpha Subunits, Gq-G11 / genetics
  • GTP-Binding Protein alpha Subunits, Gq-G11 / metabolism*
  • Male
  • Mice
  • Mice, Knockout
  • Receptors, Ghrelin / genetics
  • Receptors, Ghrelin / metabolism*

Substances

  • Ghsr1a protein, mouse
  • Receptors, Ghrelin
  • GTP-Binding Protein alpha Subunits, Gq-G11
  • Dopamine