Abstract
Mitochondrial dysfunction occurs in most neurodegenerative diseases, contributing to both their onset and progression. A recent breakthrough unveiled that propagation of the inflammatory response and subsequent neuronal injury are also mediated extracellularly by damaged mitochondria, which are released from active microglial cells into the brain milieu. These extracellular fragmented mitochondria can therefore generate sufficient toxicity to trigger neuronal death and widespread brain damage through activation of naïve astrocytes. Besides suggesting potential new pharmacological strategies of therapeutic intervention in neurodegeneration, this original work indicates that mitochondria might act as bioactive ligands exerting paracrine functions. This is an interesting, novel and impactful concept that deserves consideration by the scientific community, as the attention should now be focused on the identification of the specific receptors through which mitochondria mediate such an important extracellular signalling mechanism in neurological conditions.
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Acknowledgements
The research activities lead by M.C. are supported by the following funders, who are gratefully acknowledged: The European Research Council Consolidator Grant COG 2018–819600_FIRM; Biotechnology and Biological Sciences Research Council [grant numbers BB/M010384/1 and BB/N007042/1]; The Petplan Charitable Trust; LAM-Bighi Grant Initiative.
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Faccenda, D., Campanella, M. Mitochondria Regulate Inflammatory Paracrine Signalling in Neurodegeneration. J Neuroimmune Pharmacol 15, 565–566 (2020). https://doi.org/10.1007/s11481-020-09952-5
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DOI: https://doi.org/10.1007/s11481-020-09952-5