Neural stem cells traffic functional mitochondria via extracellular vesicles

• Published in: PLoS biology Vol. 19; no. 4; p. e3001166
• Main Authors: Peruzzotti-Jametti, Luca, Bernstock, Joshua D., Willis, Cory M., Manferrari, Giulia, Rogall, Rebecca, Fernandez-Vizarra, Erika, Williamson, James C., Braga, Alice, van den Bosch, Aletta, Leonardi, Tommaso, Krzak, Grzegorz, Kittel, Ágnes, Benincá, Cristiane, Vicario, Nunzio, Tan, Sisareuth, Bastos, Carlos, Bicci, Iacopo, Iraci, Nunzio, Smith, Jayden A., Peacock, Ben, Muller, Karin H., Lehner, Paul J., Buzas, Edit Iren, Faria, Nuno, Zeviani, Massimo, Frezza, Christian, Brisson, Alain, Matheson, Nicholas J., Viscomi, Carlo, Pluchino, Stefano
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 07.04.2021; Public Library of Science (PLoS)
• Subjects: Animals; Annotations; Assembly; ATP synthase; Biochemistry, Molecular Biology; Biological Transport; Biology and Life Sciences; Cell organelles; Cells, Cultured; Cytochrome; Cytochrome b; Cytochrome-c oxidase; Cytochromes; Dehydrogenases; Electron transport chain; Enrichment; Experiments; Extracellular vesicles; Extracellular Vesicles - metabolism; Female; Gene expression; Genomes; Genomics; Green Fluorescent Proteins - genetics; Green Fluorescent Proteins - metabolism; Life Sciences; Localization; Medicine and Health Sciences; Membranes; Mesenchymal Stem Cells - metabolism; Mesenchymal Stem Cells - physiology; Metabolism; Mice; Mice, Inbred C57BL; Mice, Transgenic; Mitochondria; Mitochondria - metabolism; Mitochondrial DNA; Morphology; Multiplexing; NADH; NADH-ubiquinone oxidoreductase; Neural stem cells; Neural Stem Cells - metabolism; Neural Stem Cells - ultrastructure; Neurobiology; Neurons; Neurons and Cognition; Nicotinamide adenine dinucleotide; Ontology; Oxidase; Oxidoreductase; Physiological aspects; Polymerase chain reaction; Proteins; Research and Analysis Methods; Stem cells; Succinate dehydrogenase; Sulfur; Ubiquinone; Ubiquinone oxidoreductase; United Kingdom; Polymerase chain reaction; Phagocytes; Vesicles; Mitochondria; Computer software; Proteomics; Outer membrane proteins; Exosomes
• ISSN: 1545-7885; 1544-9173; 1545-7885
• DOI: 10.1371/journal.pbio.3001166

Neural stem cell (NSC) transplantation induces recovery in animal models of central nervous system (CNS) diseases. Although the replacement of lost endogenous cells was originally proposed as the primary healing mechanism of NSC grafts, it is now clear that transplanted NSCs operate via multiple mechanisms, including the horizontal exchange of therapeutic cargoes to host cells via extracellular vesicles (EVs). EVs are membrane particles trafficking nucleic acids, proteins, metabolites and metabolic enzymes, lipids, and entire organelles. However, the function and the contribution of these cargoes to the broad therapeutic effects of NSCs are yet to be fully understood. Mitochondrial dysfunction is an established feature of several inflammatory and degenerative CNS disorders, most of which are potentially treatable with exogenous stem cell therapeutics. Herein, we investigated the hypothesis that NSCs release and traffic functional mitochondria via EVs to restore mitochondrial function in target cells. Untargeted proteomics revealed a significant enrichment of mitochondrial proteins spontaneously released by NSCs in EVs. Morphological and functional analyses confirmed the presence of ultrastructurally intact mitochondria within EVs with conserved membrane potential and respiration. We found that the transfer of these mitochondria from EVs to mtDNA-deficient L929 Rho 0 cells rescued mitochondrial function and increased Rho 0 cell survival. Furthermore, the incorporation of mitochondria from EVs into inflammatory mononuclear phagocytes restored normal mitochondrial dynamics and cellular metabolism and reduced the expression of pro-inflammatory markers in target cells. When transplanted in an animal model of multiple sclerosis, exogenous NSCs actively transferred mitochondria to mononuclear phagocytes and induced a significant amelioration of clinical deficits. Our data provide the first evidence that NSCs deliver functional mitochondria to target cells via EVs, paving the way for the development of novel (a)cellular approaches aimed at restoring mitochondrial dysfunction not only in multiple sclerosis, but also in degenerative neurological diseases.