A Danish study has identified the underlying mechanisms of Parkinson’s disease: small fragments of damaged mitochondrial DNA spread in brain cells.
- Parkinson’s disease is a neurodegenerative pathology, which causes tremors, slowness of movements and muscle stiffness.
- Danish researchers have suggested that damaged mitochondrial DNA could be one of the causes of Parkinson’s disease.
- Identifying disruptions in mitochondrial DNA could make it possible to diagnose Parkinson’s disease early.
Nearly 167,000 patients are affected by Parkinson’s disease in France, according to the National Institute of Health and Medical Research (Inserm). This progressive neurodegenerative pathology results in the destruction of certain neurons in the brain and the accumulation of protein clumps that are toxic to nerve cells.
Disruptions in mitochondrial DNA causing Parkinson’s disease
In a study published in the journal Molecular Psychiatristyresearchers from the University of Copenhagen (Denmark) observed that Parkinson’s disease could result from damage to mitochondria, organelles essential to the functioning of cells.
“For the first time, we can show that mitochondria, which produce vital energy in brain cells, especially neurons, suffer damage that leads to disruptions in mitochondrial DNA. This triggers and spreads disease like a wildfire in the brain (…) Our results establish that the spread of damaged genetic material, mitochondrial DNA, is at the origin of symptoms reminiscent of Parkinson’s disease and its progression to dementia.explained Professor Shohreh Issazadeh-Navikas working at the Center for Biotechnology Research and Innovation at the University of Copenhagen.
Parkinson’s: a new biomarker to identify the disease
To reach this conclusion, the Danish team analyzed human and mouse brains. Scientists then noticed that damage to mitochondria in brain cells occurs and spreads when these cells have defects in antiviral response genes. “Small fragments of DNA from the mitochondria are released into the cell. When these fragments of damaged DNA are misplaced, they become toxic to the cell, causing nerve cells to expel this toxic mitochondrial DNA (…) Being Given the interconnected nature of brain cells, these toxic DNA fragments spread to neighboring and distant cells.”, indicated the specialist. This mechanism could therefore be responsible for Parkinson’s disease.
The detection of damaged mitochondrial DNA could be a potential biomarker, in order to establish an early diagnosis of Parkinson’s disease. The Danish team also hypothesized to detect it through the bloodstream. “It is possible that damage to mitochondrial DNA in brain cells travels from the brain to the blood. This would allow a small sample of a patient’s blood to be taken to make an early diagnosis or determine the favorable response to future treatments”. For Danish scientists, this discovery could also lead to the development of future treatments.
