What is it about?

With this work we have shown that stem cels of the brain are able to release functional mitochondria via extracellular vesicles (EVs), some tiny bubbles secreted by most cells in nature, which can prospectively be used to correct mitochondrial dysfunctions in cells. By treating cells depleted of their mitochondrial DNA with stem cell-derived EVs, we were able to effectively transfer mitochondria and increase the survival of treated cells. When inflammatory macrophages were exposed to EVs, functional mitochondria were transferred and fused with the host mitochondrial network of the macrophages, which led to metabolic reprogramming and restoration of homeostasis. Ultimately, this led to a significant reduction of the detrimental pro-inflammatory effects of activated macrophages. Furthermore, using mice that had been manipulated to develop multiple sclerosis-like disease, we discovered that stem cells transplanted into sick mice were able to actively transfer EV-associated mitochondria to macrophages and microglia, thus ameliorating clinical deficits.

Featured Image

Why is it important?

Our study suggests that brain stem cells are able to release functional mitochondria via EVs that act as a survival kit for cells that present a mitochondrial dysfunction. This is of particular interest for a number of diseases in which impaired mitochondrial function is thought to contribute to pathogenesis, including progressive multiple sclerosis.

Perspectives

Our results demonstrate that mitochondrial transfer from highly regenerative stem cells contributes to their healing ability, and highlight the relevance of a novel type of intercellular signalling that could be key in promoting homeostasis and repair for regenerative neuroimmunology

Stefano Pluchino
University of Cambridge

Read the Original

This page is a summary of: Neural stem cells traffic functional mitochondria via extracellular vesicles, PLoS Biology, April 2021, PLOS,
DOI: 10.1371/journal.pbio.3001166.
You can read the full text:

Read
Open access logo

Contributors

The following have contributed to this page