Related Experiment Video
Updated: Aug 13, 2026
Improved Rodent Model of Myocardial Ischemia and Reperfusion Injury
Published on: March 7, 2022
Targeted deletion of Puma attenuates cardiomyocyte death and improves cardiac function during ischemia-reperfusion
Ambrus Toth1, John R Jeffers, Philip Nickson
1Boston Biomedical Research Institute, Watertown, MA 02472, USA.
Abstract:
The p53-upregulated modulator of apoptosis (Puma), a BH3-only member of the Bcl-2 protein family, is required for p53-dependent and -independent forms of apoptosis and has been implicated in the pathomechanism of several diseases, including cancer, acquired immunodeficiency syndrome, and ischemic brain disease. The role of Puma in cardiomyocyte death, however, has not been analyzed. On the basis of the ability of Puma to integrate diverse cell death stimuli, we hypothesized that Puma might be critical for cardiomyocyte death upon ischemia-reperfusion (I/R) of the heart. Here we show that hypoxia-reoxygenation of isolated cardiomyocytes led to an increase in Puma mRNA and protein levels. Moreover, if Puma was delivered by an adenoviral construct, cardiomyocytes died by apoptosis. Under ATP-depleted conditions, however, Puma overexpression primarily induced necrosis, suggesting that Puma is involved in the development of both types of cell death. Consistent with these findings, targeted deletion of Puma in a mouse model attenuated both apoptosis and necrosis. When the Langendorff ex vivo I/R model was used, infarcts were approximately 50% smaller in Puma(-/-) than in wild-type mice. As a result, after I/R, cardiac function was significantly better preserved in Puma(-/-) mice than in their wild-type littermates. Our study thus establishes Puma as an essential mediator of cardiomyocyte death upon I/R injury and offers a novel therapeutic target to limit cell loss in ischemic heart disease.
Insights
Puma protein is crucial for heart cell death following ischemia-reperfusion injury. Deleting Puma significantly reduced heart damage and improved cardiac function in mice, revealing Puma as a therapeutic target for heart disease.
Area of Science:
- Molecular Biology
- Cardiovascular Biology
- Cell Death Research
Background:
- Puma (p53-upregulated modulator of apoptosis) is a key regulator of apoptosis involved in various diseases.
- The role of Puma in cardiomyocyte death, particularly during cardiac ischemia-reperfusion (I/R) injury, remains uncharacterized.
Purpose of the Study:
- To investigate the role of Puma in cardiomyocyte death induced by I/R injury.
- To determine if Puma mediates apoptosis and/or necrosis in cardiomyocytes.
- To evaluate the therapeutic potential of targeting Puma in a mouse model of I/R injury.
Main Methods:
- Isolated cardiomyocytes were subjected to hypoxia-reoxygenation to assess Puma expression.
- Adenoviral constructs were used to overexpress Puma in cardiomyocytes under normal and ATP-depleted conditions.
- Puma knockout (Puma(-/-)) and wild-type mice were subjected to ex vivo Langendorff I/R to evaluate infarct size and cardiac function.
Main Results:
- Hypoxia-reoxygenation increased Puma mRNA and protein levels in cardiomyocytes.
- Puma overexpression induced apoptosis in normoxic cardiomyocytes but necrosis under ATP-depleted conditions.
- Puma(-/-) mice exhibited significantly reduced infarct size (approx. 50% smaller) and improved cardiac function after I/R compared to wild-type mice.
Conclusions:
- Puma is an essential mediator of both apoptotic and necrotic cardiomyocyte death following I/R injury.
- Targeting Puma offers a promising therapeutic strategy to limit cardiac cell loss and preserve function in ischemic heart disease.
