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Structure-activity relationships of beta-MSH derived melanocortin-4 receptor peptide agonists

Liang Zeng Yan1, Hansen M Hsiung, Mark L Heiman

  • 1Lilly Research Laboratories, A Division of Eli Lilly & Company, Lilly Corporate Center, Indianapolis, IN 46285, USA. yan_liang_zeng@lilly.com

Current Topics in Medicinal Chemistry
|June 23, 2007
PubMed

Insights

Researchers developed novel peptide agonists targeting the proopiomelanocortin (POMC)-melanocortin 4 receptor (MC4R) axis for obesity treatment. These compounds effectively reduce food intake and enhance fat metabolism in preclinical models.

Area of Science:

  • Pharmacology
  • Endocrinology
  • Medicinal Chemistry

Background:

  • Obesity is a growing global health concern requiring new pharmacologic treatments.
  • The proopiomelanocortin (POMC)-melanocortin 4 receptor (MC4R) axis is a key regulator of appetite and energy balance, making it a promising target for anti-obesity drugs.

Purpose of the Study:

  • To discover and optimize novel peptide agonists of the MC4R for potential anti-obesity therapies.
  • To investigate the in vivo efficacy and mechanism of action of these novel compounds.

Main Methods:

  • Optimization of a beta-MSH(5-22) sequence to create potent MC4R agonists.
  • Synthesis and evaluation of disulfide-constrained cyclic hexapeptides.
  • In vivo studies in rodents to assess effects on food intake and fat metabolism.
  • MC4R-deficient mouse model to confirm target engagement.

Main Results:

  • A potent MC4R agonist, Ac-Tyr-Arg-[Cys-Glu-His-D-Phe-Arg-Trp-Cys]-NH(2), was identified with in vivo efficacy in reducing food intake and increasing fat metabolism.
  • Novel cyclic hexapeptides demonstrated enhanced MC4R binding potency and selectivity over MC1R.
  • A representative analog (102) significantly reduced food intake (38%) and increased fat utilization (58%) in rats at a low dose (0.07 mg/kg).

Conclusions:

  • Developed peptide agonists targeting the POMC-MC4R pathway offer a promising avenue for obesity treatment.
  • Optimized cyclic hexapeptides represent advanced tools for studying melanocortin receptor biology.
  • These compounds hold potential for therapeutic applications in managing obesity and associated metabolic disorders.

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