Several scientific works have investigated the link between neurodegenerative disease and Mental Health, which could also be a risk factor. According to a recent study published in the British Journal of General Practiceanxiety in people over 50 could be associated with doubled risk of developing Parkinson’s disease. If this could be the case for Parkinson’s disease which is the second most common neurodegenerative condition, what about Alzheimer’s disease, first neurodegenerative disease in France, with nearly a million patients affected in France?
Alzheimer’s disease is caused by a progressive degeneration of neurons, which irreversibly affects cognitive functions such as memory, language, learning, or even reasoning. If age is the greatest known risk factor for dementia, we must not neglect the impact of other elements, such as genetics or the environment.
Mental health: a positive state of mind would protect the brain through mitochondria
A American study published on June 18, 2024 in the journal PNAS attempted to explore how mental health and feelings are likely to lead to physical changes that protect or damage the brain. To do this, the researchers analyzed data collected as part of two studies involving nearly 450 American elderly people, whose psychosocial information was collected over two decades. Study participants also donated their brains after death for further analysis, which allowed the state of their brain cells to be observed.
At the end of the study, scientists noticed that in older people who suffered less psychological stress over the course of their lives, the molecular machinery used by the mitochondria which provide energy to the brain is strengthened, compared to patients who have had more negative experiences. “We show that older people’s state of mind is linked to the biology of their brain mitochondria“, explains Caroline Trumpff, one of the authors of the study, in a press release. “Increased well-being was linked to a greater abundance of protein in mitochondria needed for energy processing, while negative mood was linked to lower protein content“, she explains. Positive feelings are therefore likely to protect the brain and thus cognitive decline and Alzheimer’s disease.
These findings shed light on the impact of mitochondria on brain biology
Conversely, more negative experiences could therefore alter the transmission of energy to the brain, and increase the risk of cognitive decline. Indeed, Caroline Trumpff argues that these discoveries are “maybe the reason why chronic psychological stress and negative experiences are harmful to the brain because they damage or impair mitochondrial energy processing in the dorsolateral prefrontal cortex, the part of the brain responsible for high-level cognitive tasks.
According to the study’s researchers, these initial results show the potential impact of mitochondria on brain health, while neurons have long been the main objects of study. “If mitochondria can modify the behavior of cells, they can modify the biology of the brainof the mind and of the person as a whole”, concludes Martin Picard, another author of this work. Nevertheless, scientists want to continue research to be able to quantify the mitochondrial health of patients’ brains, to be able to better predict the development of diseases.
Sources :
- Psychosocial experiences are associated with human brain mitochondrial biology – PNAS – 18 juin 2024
- Brain Health Is Rooted in State of Mind, Finds Study – Columbia University – 18 juin 2024
- Alzheimer’s disease – Pasteur Institute
