EZH2 inhibitor DZNep modulates microglial activation and protects against ischaemic brain injury after experimental stroke.

Abstract

Enhancer of zeste homolog-2 (EZH2), a histone methyltransferase, has been recognized to play a pivotal role in regulating the immune response in various diseases. However, its role in the inflammatory response induced by ischaemic stroke remains to be further investigated. The aim of this study was to determine the role of EZH2 in microglia-associated inflammation in ischaemic stroke and to further detect the effects of the EZH2 inhibitor, 3-deazaadenosine A (DZNep), in ischaemic brain injury. Here, we found that both in vivo ischemic/reperfusion (I/R) injury and in vitro oxygen-glucose deprivation (OGD) treatment induced a marked upregulation of EZH2 in microglia. The administration of the EZH2 inhibitor DZNep improved behavioural performance and reduced the infarct volume in mice after experimental stroke. Furthermore, we showed that DZNep blocked pro-inflammatory (CD86+) microglial activation and triggered anti-inflammatory (CD206+) microglial polarization in experimental stroke. Pro-inflammatory cytokines such as IL-1β, IL-6, TNF-α and CXCL10 were also significantly downregulated by DZNep. In addition, it was found that DZNep blocked the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in microglia, which was increased by I/R injury and OGD. Collectively, we demonstrated that EZH2 is implicated in regulating microglial activation and exacerbates neurological deficits after ischaemic stroke, probably via activating STAT3, and that the EZH2 inhibitor DZNep can exert neuroprotective effects after ischaemic stroke.

• Authors: Jian Chen, Meijuan Zhang, Xi Zhang, Lizhen Fan, Pinyi Liu, Linjie Yu, Xiang Cao, Shuwei Qiu, Yun Xu
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 857 Pg. 172452 (Aug 15 2019) ISSN: 1879-0712 [Electronic] Netherlands
• PMID: 31202798 (Publication Type: Journal Article)
• Copyright: Copyright © 2019 Elsevier B.V. All rights reserved.

Chemical References

• Neuroprotective Agents
• STAT3 Transcription Factor
• Enhancer of Zeste Homolog 2 Protein
• Tubercidin

Topics

• Animals
• Apoptosis (drug effects)
• Disease Models, Animal
• Enhancer of Zeste Homolog 2 Protein (antagonists & inhibitors)
• Infarction, Middle Cerebral Artery (complications, metabolism, pathology)
• Male
• Mice
• Mice, Inbred C57BL
• Microglia (drug effects, pathology)
• Neuroprotective Agents (pharmacology)
• Reperfusion Injury (complications)
• STAT3 Transcription Factor (metabolism)
• Tubercidin (pharmacology)
• Up-Regulation (drug effects)