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Updated: Oct 22, 2025
Improved Rodent Model of Myocardial Ischemia and Reperfusion Injury
Published on: March 7, 2022
miR-129 Attenuates Myocardial Ischemia Reperfusion Injury by Regulating the Expression of PTEN in Rats
Zhao-Hui Dai1,2, Zhi-Ming Jiang1,2, Hua Tu1
1The Affiliated Changsha Hospital of Hunan Normal University, Changsha, Hunan 410006, China.
Abstract:
PTEN/AKT signaling plays pivotal role in myocardial ischemia reperfusion injury (MIRI), and miRNAs are involved in the regulation of AKT signaling. This study was designed to investigate the interaction between miR-129 and PTEN in MIRI. A MIRI rat model and a hypoxia reoxygenation (H/R) H9C2 cell model were constructed to simulate myocardial infarction clinically. TTC staining, creatine kinase (CK) activity, TUNEL/Hoechst double staining, Hoechst staining and flow cytometer were used for evaluating myocardial infarction or cell apoptosis. miR-129 mimic transfection experiment and luciferase reporter gene assay were conducted for investigating the function of miR-129 and the interaction between miR-129 and PTEN, respectively. Real-time PCR and western blotting were performed to analyze the gene expression. Compared to the control, MIRI rats presented obvious myocardial infarction, higher CK activity, increased expression of caspase-3 and PTEN, decreased expression of miR-129, and insufficient AKT phosphorylation. Consistently, H/R significantly increased the apoptosis of H9C2 cells, concomitant with the downregulation of miR-129, upregulation of PTEN and caspase-3, and insufficient phosphorylation of AKT, while miR-129 mimic obviously inhibited the expression of PTEN and caspase-3, increased the AKT phosphorylation, and decreased the cell apoptosis. Additionally, miR-129 mimic obviously decreased the relative luciferase activity in H9C2 cells. To our best knowledge, this study firstly found that the low expression of miR-129 accelerates the myocardial cell apoptosis by directly targeting 3'UTR of PTEN. miR-129 is an important biomarker for MIRI, as well as a potential therapy target.
Insights
MicroRNA-129 (miR-129) protects against myocardial ischemia reperfusion injury (MIRI) by targeting PTEN, reducing cell apoptosis. Low miR-129 levels accelerate MIRI, highlighting its potential as a therapeutic target.
Area of Science:
- Cardiovascular Biology
- Molecular Medicine
- Cellular Signaling
Background:
- PTEN/AKT signaling is crucial in myocardial ischemia reperfusion injury (MIRI).
- MicroRNAs (miRNAs) regulate AKT signaling pathways.
- The specific role of miR-129 in MIRI remains unclear.
Purpose of the Study:
- To investigate the interaction between miR-129 and PTEN in the context of MIRI.
- To explore the therapeutic potential of miR-129 in MIRI.
Main Methods:
- Established MIRI rat and H9C2 cell models.
- Utilized TTC staining, CK activity assays, TUNEL/Hoechst staining, and flow cytometry for apoptosis assessment.
- Performed miR-129 mimic transfection, luciferase reporter assays, real-time PCR, and Western blotting.
Main Results:
- MIRI induced myocardial infarction, increased apoptosis, elevated PTEN and caspase-3, decreased miR-129, and reduced AKT phosphorylation.
- miR-129 mimic transfection reversed these effects, inhibiting PTEN/caspase-3, enhancing AKT phosphorylation, and reducing apoptosis.
- miR-129 directly targets the 3'UTR of PTEN, as confirmed by luciferase assays.
Conclusions:
- Low miR-129 expression accelerates myocardial cell apoptosis in MIRI by directly targeting PTEN.
- miR-129 acts as a protective factor against MIRI.
- miR-129 represents a potential biomarker and therapeutic target for MIRI.
