Geniposide Attenuates Post-Ischaemic Neurovascular Damage via GluN2A/AKT/ ERK-Dependent Mechanism

Cell Physiol Biochem. 2017;43(2):705-716. doi: 10.1159/000480657. Epub 2017 Sep 22.

Abstract

Background/aims: Calcium-permeable ionotropic NMDAR-mediated hyperactivity is regarded as the critical factor in modulating the development of ischaemic stroke. Recently, there has been increasing interest in preventing post-stroke neuronal death by focusing on intervening in the function of subpopulations of NMDARs and their downstream signalling. Geniposide, an iridoid glycoside, has been found to have cytoprotective functions in various conditions. However, it is still unclear whether and how geniposide affects neuronal insult under experimental stroke.

Methods: We demonstrate that dose-dependent geniposide significantly decreased the infarct volume in tMCAO models.

Results: A medium level of geniposide improved anti-apoptotic functions and inhibited BBB leakage/haemorrhage via elevating GluN2A-containing NMDAR expression in tMCAO rats. Importantly, these effects could be eliminated by co-treatment of geniposide with the GluN2A antagonist NVP but not the GluN2B inhibitor ifenprodil. Moreover, geniposide's protection was due to the enhancement of GluN2A-dependent survival signals, including pAKT, pERK and PSD-95.

Conclusion: The results suggest that geniposide protects neurons against post-ischaemic neurovascular injury through the activation of GluN2A/AKT/ERK pathways. As a very promising natural agent, geniposide may be a future therapeutic for stroke patients.

Keywords: AKT; ERK; Geniposide; GluN2A; NMDAR; TMCAO.

MeSH terms

  • Animals
  • Cell Death / drug effects
  • Extracellular Signal-Regulated MAP Kinases / analysis*
  • Infarction, Middle Cerebral Artery / drug therapy*
  • Infarction, Middle Cerebral Artery / pathology*
  • Iridoids / therapeutic use*
  • MAP Kinase Signaling System
  • Male
  • Middle Cerebral Artery / drug effects
  • Middle Cerebral Artery / pathology
  • Neurons / drug effects
  • Neurons / pathology
  • Neuroprotective Agents / therapeutic use*
  • Proto-Oncogene Proteins c-akt / analysis*
  • Rats, Sprague-Dawley
  • Receptors, N-Methyl-D-Aspartate / analysis*

Substances

  • Iridoids
  • Neuroprotective Agents
  • Receptors, N-Methyl-D-Aspartate
  • geniposide
  • Proto-Oncogene Proteins c-akt
  • Extracellular Signal-Regulated MAP Kinases
  • N-methyl D-aspartate receptor subtype 2A