Fight Aging! Newsletter, June 21st 2021

This study showed that the leakage of this mitochondrial nucleic material may occur as a result of mitochondrial dysfunction, which may involve genetic mutations in genes encoding mitochondrial proteins or incomplete degradation of mitochondrial dsDNA in the lysosome - which is a 'degradation factory' of the cell. Upon the leakage into the cytoplasm, this undegraded dsDNA is detected by a 'foreign' DNA sensor of the cytoplasm (IFI16) which then triggers the upregulation of mRNAs encoding for inflammatory proteins." Using a PD zebrafish model (gba mutant), the researchers demonstrated that a combination of PD-like phenotypes including accumulation of cytosol dsDNA deposits, reduced number of dopaminergic neurons after 3 months. Lastly, they further generated a DNase II mutant zebrafish model which exhibited decreased numbers of dopaminergic neurons and demonstrated accumulated cytosolic DNA. Interestingly, when the gba mutant zebrafish was complemented with human DNAse II gene, the overexpression of human DNAse II decreased cytosolic dsDNA deposits, rescued neuro-degradation by rescuing the number of dopaminergic and noradrenergic neurons after 3 months. This demonstrated that neurodegenerative phenotype of gba mutant zebrafish induced by dsDNA deposits in the cytosol can be restored by DNAse II. In a step further, to determine the effect of cytosolic dsDNA of mitochondrial origin in human brain with PD, researchers inspected postmortem human brain tissues from p...
Source: Fight Aging! - Category: Research Authors: Tags: Newsletters Source Type: blogs