Generation of mitochondrial-activated amnion-derived mesenchymal stromal cells for the treatment of Duchenne muscular dystrophy-associated cardiomyopathy
Y Maruo, J Abe, M Hayashi, A Takeda, S Ohnishi, Y YamadaAbstract
Background
Cardiomyopathy in Duchenne muscular dystrophy (DMD), has become a major determinant of prognosis as advances in respiratory care prolong survival. DMD-associated cardiomyopathy is characterized by early-onset, progressive mitochondrial dysfunction driven by dystrophin deficiency. Although heart transplantation is feasible only in exceptional cases worldwide, most patients lack definitive treatment options. Recent advances in DMD therapy, particularly gene-based approaches, have transformed disease management; however, their impact on established cardiomyopathy remains limited, highlighting the growing importance of regenerative medicine. Among regenerative strategies, mesenchymal stromal cell (MSC) therapy has shown promise for cardiac repair but is constrained by the mitochondria-compromised and oxidative myocardial environment. We hypothesized that mitochondrial activation of MSCs could enhance their therapeutic potential for DMD-associated cardiomyopathy. Although this mitochondrial activation strategy is not disease-specific, DMD-associated cardiomyopathy represents an ideal initial disease model due to its profound mitochondrial vulnerability and critical unmet clinical need.
Purpose
To generate mitochondrial-activated amnion-derived mesenchymal stromal cells (AMSCs) by targeted mitochondrial delivery of Coenzyme Q10 (CoQ10) and to evaluate their mitochondrial bioenergic and antioxidant properties as a preparatory step toward cell therapy for DMD-associated cardiomyopathy (Picture 1).
Methods
Human AMSCs were treated with CoQ10-encapsulated MITO-Porter, a mitochondria-fusogenic nanocarrier. Cellular uptake was quantified by flowcytometry, mitochondrial co-localization was evaluated by confocal laser scanning microscopy, mitochondrial oxygen consumption rate (OCR) was measured using an extracellular flux analyzer, and mitochondrial superoxide levels were evaluated to assess antioxidant capacity.
Results
Flowcytometry demonstrated robust cellular uptake of CoQ10-encapsulated MITO-Porter. Confocal microscopy confirmed mitochondrial co-localization of the nanocarrier (Picture 2). Functionally, treatment with CoQ10-encapsulated MITO-Porter significantly increased mitochondrial OCR (basal: p<0.01; maximal: p<0.05) compared with non-treated and naked CoQ10-treated AMSCs. In parallel, intracellular mitochondrial superoxide production was significantly reduced (p<0.05), indicating improved mitochondrial bioenergetics and antioxidant defense.
Conclusion
Mitochondria-targeted delivery of CoQ10 successfully generated mitochondrial-activated human AMSCs with enhanced respiratory capacity and reduced oxidative stress. These findings support mitochondrial activation as a promising strategy to improve MSC-based therapy for DMD-associated cardiomyopathy and provide a strong rationale for further preclinical evaluation in dystrophic heart models.