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Updated: Jun 28, 2026
Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration
Published on: September 6, 2014
Injection of isolated mitochondria during early reperfusion for cardioprotection
James D McCully1, Douglas B Cowan, Christina A Pacak
1Division of Cardiothoracic Surgery, Beth Israel Deaconess Medical Center, Harvard Institutes of Medicine, 77 Ave. Louis Pasteur, Rm. 144, Boston, MA 02115, USA. james_mccully@hms.harvard.edu
Abstract:
Previously, we demonstrated that ischemia induces mitochondrial damage and dysfunction that persist throughout reperfusion and impact negatively on postischemic functional recovery and cellular viability. We hypothesized that viable respiration-competent mitochondria, isolated from tissue unaffected by ischemia and then injected into the ischemic zone just before reperfusion, would enhance postischemic functional recovery and limit infarct size. New Zealand White rabbits (n = 52) were subjected to 30 min of equilibrium and 30 min of regional ischemia (RI) induced by snaring the left anterior descending coronary artery. At 29 min of RI, the RI zone was injected with vehicle (sham control and RI vehicle) or vehicle containing mitochondria (7.7 x 10(6) +/- 1.5 x 10(6)/ml) isolated from donor rabbit left ventricular tissue (RI-Mito). The snare was released at 30 min of RI, and the hearts were reperfused for 120 min. Our results show that left ventricular peak developed pressure and systolic shortening in RI-Mito hearts were significantly enhanced (P < 0.05 vs. RI-vehicle) to 75% and 83% of equilibrium value, respectively, at 120 min of reperfusion compared with 57% and 62%, respectively, in RI-vehicle hearts. Creatine kinase-MB, cardiac troponin I, and infarct size relative to area at risk were significantly decreased in RI-Mito compared with RI-vehicle hearts (P < 0.05). Confocal microscopy showed that injected mitochondria were present and viable after 120 min of reperfusion and were distributed from the epicardium to the subendocardium. These results demonstrate that viable respiration-competent mitochondria, isolated from tissue unaffected by ischemia and then injected into the ischemic zone just before reperfusion, significantly enhance postischemic functional recovery and cellular viability.
Insights
Injecting healthy mitochondria into the heart before reperfusion significantly improves cardiac function and reduces heart attack damage. This novel approach enhances recovery after ischemia and reperfusion injury.
Area of Science:
- Cardiology
- Mitochondrial Medicine
- Regenerative Medicine
Background:
- Ischemia causes persistent mitochondrial damage, impairing heart function and viability post-reperfusion.
- Mitochondrial dysfunction is a key factor in negative outcomes following ischemic events.
- Targeting mitochondria offers a potential therapeutic strategy for myocardial recovery.
Purpose of the Study:
- To investigate if transplanting healthy, functional mitochondria into the ischemic zone before reperfusion can improve cardiac function and limit infarct size.
- To test the hypothesis that exogenous mitochondria can restore cellular viability and enhance recovery after regional ischemia.
- To assess the efficacy of mitochondria transplantation as a treatment for ischemia-reperfusion injury.
Main Methods:
- New Zealand White rabbits underwent 30 minutes of regional ischemia (RI) followed by reperfusion.
- Before reperfusion, the ischemic zone was injected with either vehicle or isolated, viable mitochondria (RI-Mito).
- Cardiac function, infarct size, and biomarker levels were measured after 120 minutes of reperfusion; injected mitochondria viability and distribution were confirmed via confocal microscopy.
Main Results:
- Hearts treated with mitochondria (RI-Mito) showed significantly enhanced left ventricular peak developed pressure and systolic shortening compared to controls.
- Creatine kinase-MB, cardiac troponin I levels, and infarct size relative to the area at risk were significantly reduced in the RI-Mito group.
- Injected mitochondria were found to be viable and distributed throughout the myocardial tissue from epicardium to subendocardium after reperfusion.
Conclusions:
- Transplantation of viable, respiration-competent mitochondria into the ischemic zone before reperfusion significantly improves post-ischemic functional recovery.
- Mitochondria injection effectively limits infarct size and enhances cellular viability in the setting of regional ischemia.
- This study demonstrates the therapeutic potential of exogenous mitochondria for treating ischemia-reperfusion injury in the heart.
