Acteoside alleviates blood-brain barrier damage induced by ischemic stroke through inhibiting microglia HMGB1/TLR4/NLRP3 signaling

Biochem Pharmacol. 2024 Feb:220:115968. doi: 10.1016/j.bcp.2023.115968. Epub 2023 Dec 15.

Abstract

Ischemic stroke (IS) can cause severe harm, inducing oxidative stress, inflammation, and pyroptotic death. IS treatment efficacy remains limited, and microglia are important regulators of IS-related blood-brain barrier (BBB) damage. It is thus vital that new therapeutic agents capable of targeting microglia be identified to treat IS-related damage to the BBB. Acteoside (ACT), which is a compound derived from Cistanche tubulosa (Schenk) Wight., offers promising bioactivity, but its ability to protect against central nervous system injury remains to be documented. To clarify the protective benefits and mechanisms through which ACT can protect against damage to the BBB, a rat middle cerebral artery occlusion (MCAO) model system was herein employed. These in vivo analyses demonstrated that ACT was able to significantly reduce cerebral infarct size while improving their neurological scores and altering neurotrophic and inflammatory factor release. RNA sequencing and molecular docking studies highlighted the ability of ACT to exert its protective benefits via the HMGB1/TLR4/NLRP3 axis. Western immunoblotting and immunofluorescent staining for tight junction proteins additionally confirmed the ability of ACT to preserve BBB integrity. The underlying mechanisms were then explored with an oxygen-glucose deprivation (OGD) model in vitro with BV2 cells. This strategy thus confirmed that the ability of ACT to suppress microglial inflammatory and pyroptotic activity was HMGB1/TLR4/NLRP3 pathway-dependent. These data thus offer novel evidence that ACT can protect against IS-related damage to the BBB through the abrogation of inflammatory and pyroptotic activity, underscoring its promise as a novel lead compound for the therapeutic treatment of IS.

Keywords: Acteoside; Blood-brain barrier; HMGB1/TLR4/NLRP3 signaling pathway; Ischemic stroke; Microglia.

MeSH terms

  • Animals
  • Blood-Brain Barrier / metabolism
  • Brain Ischemia*
  • Glucosides*
  • HMGB1 Protein* / metabolism
  • Ischemic Stroke* / drug therapy
  • Microglia / metabolism
  • Molecular Docking Simulation
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Polyphenols*
  • Rats
  • Reperfusion Injury*
  • Stroke* / drug therapy
  • Toll-Like Receptor 4 / metabolism

Substances

  • Toll-Like Receptor 4
  • HMGB1 Protein
  • acteoside
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Glucosides
  • Polyphenols