Evaluation of analgesic and anti-inflammatory activity of purine-2,6-dione-based TRPA1 antagonists with PDE4/7 inhibitory activity

Pharmacol Rep. 2022 Oct;74(5):982-997. doi: 10.1007/s43440-022-00397-6. Epub 2022 Aug 5.

Abstract

Background: To verify the validity of the proposed pain treatment approach, which is based on concomitant blocking of the Transient Receptor Potential Ankyrin 1 (TRPA1) channel and phosphodiesterases (PDEs) 4B/7A activity, we continued our pharmacological studies on 8-alkoxypurine-2,6-diones selected based on previous in vitro screening.

Methods: Derivatives 17, 31, and 36 were pharmacologically evaluated in vivo using the formalin test and oxaliplatin-induced neuropathic pain: the von Frey and the cold plate tests, and in the carrageenan-induced edema model. Compound 36, which turned out to be the most promising, was further evaluated in the collagen-induced arthritis model. The pharmacokinetic parameters of this compound were also estimated.

Results: All the tested compounds exhibited significant analgesic and anti-inflammatory activities. Compound 36 was additionally characterized by an antiarthritic effect and showed a favorable pharmacokinetic profile in rats.

Conclusion: The compounds evaluated in this study represent a new class of derivatives with analgesic and anti-inflammatory activities that involve TRPA1 antagonism and PDE4/7 inhibition.

Keywords: Analgesic activity; Anti-inflammatory activity; Antiarthritic effect; PDE4/7 inhibitors; Purine-2,6-diones; TRPA1 antagonists.

MeSH terms

  • Analgesics / pharmacology
  • Analgesics / therapeutic use
  • Animals
  • Ankyrins*
  • Anti-Inflammatory Agents / pharmacology
  • Carrageenan
  • Oxaliplatin
  • Phosphoric Diester Hydrolases
  • Purines / pharmacology
  • Rats
  • TRPA1 Cation Channel
  • Transient Receptor Potential Channels*

Substances

  • TRPA1 Cation Channel
  • Carrageenan
  • Oxaliplatin
  • Ankyrins
  • Analgesics
  • Anti-Inflammatory Agents
  • Transient Receptor Potential Channels
  • Purines
  • Phosphoric Diester Hydrolases
  • Trpa1 protein, rat