Orally active ghrelin receptor inverse agonists and their actions on a rat obesity model

Bioorg Med Chem. 2015 Aug 1;23(15):4792-4803. doi: 10.1016/j.bmc.2015.05.047. Epub 2015 Jun 9.

Abstract

A series of 2-alkylamino nicotinamide analogs was prepared as orally active ghrelin receptor (ghrelinR) inverse agonists. Starting from compound 1, oral bioavailability was improved by modifying metabolically unstable sites and reducing molecular weight. Brain-permeable compound 33 and compound 24 with low brain permeability were tested in rat models of obesity; 30 mg/kg of compound 33 suppressed weight gain. PK/PD analysis revealed that the anti-obesity effect of ghrelinR inverse agonists depends on their brain concentrations.

Keywords: 2-Aminoalkyl nicotinamide; GhrelinR; Inverse agonist; Obesity.

MeSH terms

  • Administration, Oral
  • Animals
  • Anti-Obesity Agents / administration & dosage
  • Anti-Obesity Agents / chemistry*
  • Anti-Obesity Agents / pharmacokinetics
  • Disease Models, Animal
  • Drug Inverse Agonism
  • Half-Life
  • Humans
  • Male
  • Mice
  • Mice, Inbred ICR
  • Microsomes, Liver / metabolism
  • Niacinamide / administration & dosage
  • Niacinamide / chemistry
  • Niacinamide / pharmacokinetics
  • Obesity / drug therapy
  • Obesity / pathology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Ghrelin / agonists*
  • Receptors, Ghrelin / metabolism
  • Structure-Activity Relationship

Substances

  • Anti-Obesity Agents
  • Receptors, Ghrelin
  • Niacinamide