Can Cells Share Their Batteries? Mitochondrial Transfer and the Long Road to a Longevity Treatment

Edited and Approved by Stephen C. Rose, PhD, MS

Mitochondria are often described as the powerhouses of the cell because they produce much of the energy cells use. Their role is broader, however: they also influence cell growth, stress signaling, inflammation, and programmed cell death. These functions become less reliable in aging tissues. One possible therapeutic response is to replace damaged mitochondria, and researchers now know that cells can naturally transfer mitochondria to one another.

That discovery has led to a direct therapeutic proposal: isolate functional mitochondria, deliver them to injured cells, and determine whether the recipients recover energy production and cellular function. The approach is scientifically credible, but its longevity applications remain hypothetical. No clinical trial has shown that mitochondrial transfer slows human aging or extends lifespan. Current research is testing whether mitochondrial exchange can rescue acutely damaged tissues, especially the heart and brain [1] [2].

The cellular extension cord

Cells move mitochondria through several routes. Thin actin-based bridges called tunneling nanotubes can connect two cells directly. Extracellular vesicles can package whole mitochondria or mitochondrial components. Cells can also release free mitochondria that another cell engulfs. A 2026 cardiovascular review organizes the biology into two useful functions: "Rescue by Replenish," in which functional material restores energy production or stress resistance, and "Relief by Release," in which a cell exports damaged mitochondrial cargo for disposal [1]. Both processes may help tissues preserve metabolic function and remove damaged material.

Foundational experiments support the mechanism. In 2006, adult stem cells transferred mitochondria to human cells stripped of functional mitochondrial DNA and restored aerobic respiration [3]. In mice with acute lung injury, bone-marrow stromal cells donated mitochondria to alveolar cells, increasing ATP and improving survival; donor cells with defective mitochondria did not provide the same protection [4]. After experimental stroke, astrocytes transferred mitochondria to neurons, and disrupting the pathway worsened neurological outcomes [5]. In the healthy mouse heart, cardiomyocytes can also eject dysfunctional mitochondria for resident macrophages to clear, linking organelle disposal to tissue homeostasis [6]. These findings establish a biological mechanism, not a human rejuvenation treatment.

Why longevity researchers are interested

Mitochondrial dysfunction is closely linked to aging: energy production changes, quality-control systems become less reliable, inflammatory signals rise, and mixtures of normal and mutant mitochondrial DNA can shift across tissues. In mice, inherited mitochondrial DNA mutations can aggravate premature-aging features and impair brain development [7]. If damaged cells can accept functional organelles, selected tissues might eventually be restored without altering every cell. Researchers have proposed engineered mitochondria, protective coatings, targeting systems, and combination therapies to improve delivery and persistence [8]. These are plausible research directions, not evidence that mitochondrial infusion rejuvenates an aging organism.

The central difficulty is that mitochondrial transfer is highly context-dependent. Cancer cells can acquire mitochondria from immune cells through nanotubes, strengthening tumor metabolism while depleting the immune cells meant to attack them [9]. Transferred mitochondria may be destroyed, provide only temporary support, or become durably integrated; researchers do not yet know how to predict these outcomes. Donor age, mitochondrial DNA compatibility, inflammation, tissue targeting, dose, storage, manufacturing consistency, and immune activation all matter [1,2]. A successful therapy will therefore require precise targeting and careful monitoring for unintended effects, including tumor support.

What has actually reached patients

Human studies have concentrated on ischemia-reperfusion injury, where blood supply returns after deprivation and damaged mitochondria help amplify cell injury. At Boston Children's Hospital, NCT02851758 is recruiting children supported by ECMO after cardiac ischemia. Investigators isolate mitochondria from the patient's skeletal muscle and inject or infuse them into the injured heart; the estimated enrollment is 16 and the primary outcome is short-term safety [10]. A related report described pediatric patients treated after cardiogenic shock, but it was a small observational experience rather than a randomized proof of benefit [11].

For stroke, NCT04998357 is listed as recruiting 20 participants undergoing thrombectomy. A small muscle biopsy is processed at the bedside and the patient's mitochondria are infused through a microcatheter into the affected cerebral artery [12]. Published phase 1 results reported feasibility and no signal of major procedure-related harm, but the study was open-label and designed for safety, not longevity or definitive efficacy [13]. A separate randomized trial in 30 people with acute heart attack tested intracoronary platelet-derived mitochondria. Exercise capacity improved and ejection fraction improved slightly more in the treatment group, but the study was small and followed participants for only 40 days [14].

One registered CABG study, NCT05669144, planned four groups of five patients receiving mesenchymal-cell exosomes, autologous mitochondria, both, or placebo. Its registry status is now "unknown" because the record has not been verified since December 2022 [15]. Taken together, the clinical evidence says: early human feasibility in severely injured organs, with tantalizing signals and enormous uncertainty. It does not say: systemic mitochondrial renewal, slower biological aging, or longer life. As of September 2026, no registered trial identified here tests mitochondrial transfer as a treatment for aging itself.

Aubrey de Grey, slow mitochondria, and a different kind of transfer

Aubrey de Grey's mitochondrial work belongs in this story, but in the correct drawer. His "Survival of the Slowest" or reductive-hotspot hypothesis proposed that certain respiration-deficient cells might persist because altered metabolism protects them from forms of mitochondrial damage, while their exported reactive chemistry harms circulating lipids and distant tissues [16]. It is an inventive hypothesis, not settled doctrine. Modern human data further complicate any single-mutation narrative: age-related mitochondrial variants in blood appear strongly shaped by ordinary replication errors and expansion of blood-cell clones, often behaving more like markers of clonal hematopoiesis than universally selected drivers of aging [17].

MitoSENS pursues allotopic expression: making backup versions of mitochondrial genes in the cell nucleus, attaching import instructions, and sending the resulting proteins back into mitochondria. This is not mitochondrial transfer between cells. It is gene relocation within a cell. SENS-supported researchers reported that nuclear expression of ATP8 and ATP6 restored important functions in a mutant human cell model [18]. The result is a meaningful cellular proof of concept, but the field has long argued about whether highly hydrophobic mitochondrial proteins are truly imported and assembled. Earlier experiments warned that apparent rescue can be caused by revertant cells or proteins lingering outside the organelle [19]. MitoSENS therefore addresses one proposed source of mitochondrial failure; it does not yet demonstrate organism-wide rejuvenation.

The reasonable version of the future

Mitochondrial transfer may become useful first where the target is local, the injury is acute, and minutes matter: an ischemic heart, a stroke territory, perhaps a transplanted organ. Longevity applications would require far more—cell-specific delivery, proof that transferred organelles remain functional, surveillance for cancer and inflammation, reproducible manufacturing, and trials measuring durable function rather than a temporary ATP surge. The same caution applies to mitochondrial gene backup: elegant engineering must still survive delivery, integration, long-term safety, and whole-organism biology.

Cells can therefore share functional mitochondria, but the central clinical question is whether medicine can control the donor, recipient, persistence, and long-term effects of that transfer. Mitochondrial transfer is not yet a longevity treatment. It is a biologically grounded technology entering early human testing, with enough promise to justify careful experiments and enough unresolved risk to require rigorous, long-term evaluation.

References

1. Ikeda G, Li J, Wang A, Paleru AM, Yang PC. Mitochondrial Transfer: From Bench to Bedside. Circ Res. 2026;138(8):e326984. doi:10.1161/CIRCRESAHA.125.326984.

2. Borcherding N, Brestoff JR. The power and potential of mitochondria transfer. Nature. 2023;623(7986):283-291. doi:10.1038/s41586-023-06537-z.

3. Spees JL, Olson SD, Whitney MJ, Prockop DJ. Mitochondrial transfer between cells can rescue aerobic respiration. Proc Natl Acad Sci U S A. 2006;103(5):1283-1288. doi:10.1073/pnas.0510511103.

4. Islam MN, Das SR, Emin MT, et al. Mitochondrial transfer from bone-marrow-derived stromal cells to pulmonary alveoli protects against acute lung injury. Nat Med. 2012;18(5):759-765. doi:10.1038/nm.2736.

5. Hayakawa K, Esposito E, Wang X, et al. Transfer of mitochondria from astrocytes to neurons after stroke. Nature. 2016;535(7613):551-555. doi:10.1038/nature18928.

6. Nicolás-Ávila JA, Lechuga-Vieco AV, Esteban-Martínez L, et al. A Network of Macrophages Supports Mitochondrial Homeostasis in the Heart. Cell. 2020;183(1):94-109.e23. doi:10.1016/j.cell.2020.08.031.

7. Ross JM, Stewart JB, Hagström E, et al. Germline mitochondrial DNA mutations aggravate ageing and can impair brain development. Nature. 2013;501(7467):412-415. doi:10.1038/nature12474.

8. Zhao R, Dong C, Liang Q, et al. Engineered Mitochondrial Transplantation as An Anti-Aging Therapy. Aging Dis. 2025;16(4):1918-1945. doi:10.14336/AD.2024.0231.

9. Saha T, Dash C, Jayabalan R, et al. Intercellular nanotubes mediate mitochondrial trafficking between cancer and immune cells. Nat Nanotechnol. 2022;17(1):98-106. doi:10.1038/s41565-021-01000-4.

10. ClinicalTrials.gov. Transplantation of Autologously Derived Mitochondria Following Ischemia. Identifier NCT02851758. Updated January 5, 2026.

11. Guariento A, Piekarski BL, Doulamis IP, et al. Autologous mitochondrial transplantation for cardiogenic shock in pediatric patients following ischemia-reperfusion injury. J Thorac Cardiovasc Surg. 2021;162(3):992-1001. doi:10.1016/j.jtcvs.2020.10.151.

12. ClinicalTrials.gov. Autologous Mitochondrial Transplant for Cerebral Ischemia. Identifier NCT04998357. Updated May 21, 2025.

13. Walker M, Kim CY, Elmore ZC, et al. Autologous mitochondrial transplant for acute cerebral ischemia: Phase 1 trial results and review. J Cereb Blood Flow Metab. 2026;46(2):322-332. doi:10.1177/0271678X241305230.

14. Baharvand F, Habibi Roudkenar M, Pourmohammadi-Bejarpasi Z, et al. Safety and efficacy of platelet-derived mitochondrial transplantation in ischaemic heart disease. Int J Cardiol. 2024;410:132227. doi:10.1016/j.ijcard.2024.132227.

15. ClinicalTrials.gov. Co-transplantation of Mesenchymal Stem Cell Derived Exosomes and Autologous Mitochondria for Patients Candidate for CABG Surgery. Identifier NCT05669144. Status unknown; last verified December 2022.

16. de Grey ADNJ. The reductive hotspot hypothesis of mammalian aging: membrane metabolism magnifies mutant mitochondrial mischief. Eur J Biochem. 2002;269(8):2003-2009. doi:10.1046/j.1432-1033.2002.02868.x.

17. Gupta R, Durham TJ, Chau G, et al. Mechanism of age-related accumulation of mitochondrial DNA mutations in human blood. Nature. 2026;656(8126):140-148. doi:10.1038/s41586-026-10569-6.

18. Boominathan A, Vanhoozer S, Basisty N, et al. Stable nuclear expression of ATP8 and ATP6 genes rescues a mtDNA Complex V null mutant. Nucleic Acids Res. 2016;44(19):9342-9357. doi:10.1093/nar/gkw756.

19. Perales-Clemente E, Fernández-Silva P, Acín-Pérez R, Pérez-Martos A, Enríquez JA. Allotopic expression of mitochondrial-encoded genes in mammals: achieved goal, undemonstrated mechanism or impossible task? Nucleic Acids Res. 2011;39(1):225-234. doi:10.1093/nar/gkq769.