Related Experiment Video
Updated: Nov 12, 2025
Two-vessel Occlusion Mouse Model of Cerebral Ischemia-reperfusion
Published on: March 1, 2019
PKM2 Aggravates Cerebral Ischemia Reperfusion-Induced Neuroinflammation via TLR4/MyD88/TRAF6 Signaling Pathway
Baocheng Zhang1, Jie Shen2, Zhiyue Zhong1
1Department of Intensive Care Unit, Jinshan Hospital Affiliated to Fudan University, Shanghai, China.
Objectives:
Cerebral ischemia-reperfusion (I/R) injury is the leading cause of ischemic stroke. Pyruvate Kinase isozymes M2 (PKM2), as a critical glycolytic enzyme during glycolysis, is involved in neuronal apoptosis in rats with hypoxic-ischemic encephalopathy. This study focused on functional investigation and potential molecular mechanism toward PKM2 in cerebral I/R injury.
Methods:
Cerebral I/R injury model was established by middle cerebral artery occlusion (MCAO) in vivo or oxygen-glucose deprivation and reoxygenation (OGD/R) in vitro. qRT-PCR and Western blot were used to detect the expression of PKM2 in I/R injury models. The effects of PKM2 on I/R injury were determined via triphenyl tetrazolium chloride staining and evaluation of neurological deficits. Cell Counting Kit-8 was employed to detect cell viability, and ELISA was conducted to detect pro-inflammatory cytokines. The underlying mechanism involved in regulation of PKM2 on I/R injury was investigated via ELISA and Western blot.
Results:
PKM2 was upregulated after cerebral I/R injury. Knockdown of PKM2 alleviated MCAO-induced infarction and neurological dysfunction. Moreover, PKM2 knockdown also alleviated OGD/R-induced neuronal cell injury and inflammatory response. Mechanistically, PKM2 knockdown-induced neuroprotection was accompanied by inhibition of high-mobility group box 1 (HMGB1), reflected by inactivation of TLR4/MyD88 (myeloid differentiation factor 88)/TRAF6 (TNF receptor-associated factor 6) signaling pathway.
Conclusions:
Knockdown of PKM2 attenuated cerebral I/R injury through HMGB1-mediated TLR4/MyD88/TRAF6 expression change, providing a potential target for cerebral I/R injury treatment.
Insights
Pyruvate Kinase isozymes M2 (PKM2) is upregulated in cerebral ischemia-reperfusion injury. Reducing PKM2 levels protects against stroke by inhibiting inflammation and neuronal damage via the HMGB1/TLR4 pathway.
Area of Science:
- Neuroscience
- Molecular Biology
- Biochemistry
Background:
- Cerebral ischemia-reperfusion (I/R) injury is a primary cause of ischemic stroke.
- Pyruvate Kinase isozymes M2 (PKM2), a key glycolytic enzyme, plays a role in neuronal apoptosis in hypoxic-ischemic encephalopathy.
Purpose of the Study:
- To investigate the function of PKM2 in cerebral I/R injury.
- To explore the underlying molecular mechanisms of PKM2's involvement in I/R injury.
Main Methods:
- Established in vivo (MCAO) and in vitro (OGD/R) models of cerebral I/R injury.
- Assessed PKM2 expression using qRT-PCR and Western blot.
- Evaluated the impact of PKM2 on infarction, neurological deficits, cell viability, and inflammatory cytokines.
Main Results:
- PKM2 expression was significantly upregulated following cerebral I/R injury.
- Knockdown of PKM2 reduced infarct size and improved neurological function in MCAO models.
- PKM2 knockdown mitigated neuronal injury and inflammation in OGD/R models, associated with inhibition of HMGB1 and the TLR4/MyD88/TRAF6 pathway.
Conclusions:
- PKM2 knockdown demonstrates neuroprotective effects against cerebral I/R injury.
- The mechanism involves the inhibition of the HMGB1-mediated TLR4/MyD88/TRAF6 signaling pathway.
- PKM2 represents a potential therapeutic target for treating cerebral I/R injury.
