Agomelatine Exerts an Anti-inflammatory Effect by Inhibiting Microglial Activation Through TLR4/NLRP3 Pathway in pMCAO Rats

Neurotox Res. 2022 Feb;40(1):259-266. doi: 10.1007/s12640-021-00447-6. Epub 2021 Nov 29.

Abstract

Cerebral ischemic stroke is one of the main causes of death and long-term disability worldwide. However, the mechanism is unclear, and treatments are limited. In this study, we aimed to investigate the anti-inflammatory effect of agomelatine in a permanent middle cerebral artery occlusion (pMCAO) model. Forty-eight male Wistar rats were randomly divided into four groups: sham, pMCAO + vehicle, pMCAO + agomelatine (40 mg/kg, i.p.), and pMCAO + melatonin (10 mg/kg, i.p.) groups. On day 1 after permanent cerebral ischemia, the animals were sacrificed, and brain tissues were collected for western blot analysis, and immunohistochemistry. Agomelatine treatment ameliorated inflammatory responses by decreasing the protein levels of trigger Toll-like receptor (TLR4)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway components together with nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome components. In addition, agomelatine suppressed microglial activation and pyroptotic cell death after cerebral ischemic injury. These results suggest that agomelatine exerts an anti-inflammatory effect and attenuates brain damage by inhibiting microglial activation through the TLR4/NLRP3 signaling pathway.

Keywords: Agomelatine; Inflammation; Melatonin; NLRP3 inflammasome; Permanent cerebral ischemia.

MeSH terms

  • Acetamides
  • Animals
  • Anti-Inflammatory Agents / pharmacology
  • Anti-Inflammatory Agents / therapeutic use
  • Brain Ischemia* / drug therapy
  • Infarction, Middle Cerebral Artery / complications
  • Infarction, Middle Cerebral Artery / drug therapy
  • Male
  • Microglia / metabolism
  • NF-kappa B / metabolism
  • NLR Family, Pyrin Domain-Containing 3 Protein*
  • Naphthalenes
  • Rats
  • Rats, Sprague-Dawley
  • Rats, Wistar
  • Toll-Like Receptor 4 / metabolism

Substances

  • Acetamides
  • Anti-Inflammatory Agents
  • NF-kappa B
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Naphthalenes
  • Nlrp3 protein, rat
  • Tlr4 protein, rat
  • Toll-Like Receptor 4
  • agomelatine