Research Paper Volume 15, Issue 9 pp 3635—3643

TIMP2 facilitates CIRI through activating NLRP3-mediated pyroptosis

Shaoyong Shi1, , Chongyang Zhang1, , Jiaxiang Liu1, ,

  • 1 Department of Prehospital Emergency Care, Qinhuangdao First Hospital, Qinhuangdao 066000, China

Received: February 1, 2023       Accepted: April 17, 2023       Published: May 12, 2023
How to Cite

Copyright: © 2023 Shi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


This study aimed to investigate the underlying mechanisms of cerebral ischemia-reperfusion injury (CIRI) in mice using CIR and hypoxia/reoxygenation (H/R) cell models. The study evaluated brain tissue weight, pathological injury, and changes in the expression levels of TIMP2, p-ERK1/2 and NLRP3-mediated pyroptosis-related proteins in brain tissues and hippocampal neurons of CIR mice using established methods such as dry/wet weight measurement, HE staining, qPCR, TUNEL assay, and Western blotting. The results demonstrated a significant increase in brain water content and neuronal apoptosis rate in the experimental groups compared with those in the control group. In particular, the I/R+TIMP2 group showed the highest increase. Additionally, the control group exhibited a clear brain tissue structure, neatly and densely arranged cells with normal morphology, and evenly stained and clear hippocampal tissues. However, the I/R group showed hippocampal structure disorders, interstitial edema, deep nuclear staining, karyopyknosis, and karyorrhexis in brain tissues. The study results further revealed that TIMP2 could aggravate the pathological damage of brain tissues in the I/R+TIMP2 group compared with the I/R group and significantly reduced it in the TIMP2-KD group. Furthermore, the Western blotting results demonstrated that the protein expression levels of TIMP2, p-ERK1/2, t-ERK1/2, NLRP3, IL-1β, IL-18, GSDMD, Caspase-1, and ASC in brain tissues and hippocampal neurons were significantly higher in the experimental groups than those in the control group. The I/R+TIMP2 group displaying the highest increase and the TIMP2-KD group showing a significant decrease. In conclusion, TIMP2 can contribute to the occurrence and progression of CIRI by activating NLRP3-mediated pyroptosis.


CIRI: cerebral ischemia reperfusion injury; I/R: ischemia reperfusion; H/R: hypoxia/reoxygenation; TIMP2: tissue inhibitor of metalloproteinase 2; ERK1/2: extracellular signal-regulated kinase 1/2; NLRP3: Nod-like receptor protein 3; HE: hematoxylin-eosin; TUNEL: terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling; IL-1β: interleukin-1β; GSDMD: gasdermin D.