Parkinson’s disease is one of the most common brain disorders affecting older adults. Millions of people around the world live with the condition, and the number continues to grow as populations age.
The disease mainly affects movement, causing shaking, stiff muscles, slow movement, and problems with balance and walking. As it progresses, many people also develop difficulties with memory, thinking, sleep, mood, and eventually dementia.
Although medicines can help control symptoms, there is still no cure that can stop the disease from getting worse. That is why scientists continue searching for its underlying causes.
Now, researchers at the University of Copenhagen have made an important discovery that could change how scientists understand Parkinson’s disease. Their study suggests that a major problem is a blockage in the system that keeps tiny structures inside cells, called mitochondria, healthy and working properly.
Mitochondria are often described as the power stations of cells because they produce the energy every cell needs to survive and perform its normal tasks.
Brain cells need especially large amounts of energy because they are constantly sending signals throughout the nervous system. Healthy cells regularly remove old or damaged mitochondria and replace them with new ones. This natural cleaning process keeps cells functioning efficiently.
The researchers found that in Parkinson’s disease this cleaning system does not work properly. Instead of being removed, damaged mitochondria build up inside brain cells. As more faulty mitochondria collect, the cells produce less energy and become increasingly unhealthy. Over time, many of these brain cells die.
This gradual loss of nerve cells is believed to be responsible for the movement problems that are the hallmark of Parkinson’s disease. It may also contribute to memory loss and dementia that develop in many patients.
One of the most surprising findings was the connection with the immune system. Scientists have traditionally focused on proteins that build up in the brain or on aging itself.
However, this study suggests that genes involved in the body’s immune response also play an important role. Some of these genes normally help cells respond to viral infections, including viruses such as COVID-19. The researchers discovered that these same genes are also involved in maintaining the system that protects healthy mitochondria.
In people with Parkinson’s disease, these immune-related genes appear to stop working normally. Instead of protecting brain cells, they may interfere with the normal cleaning process, allowing damaged mitochondria to accumulate. This discovery suggests that the immune system has a much larger role in brain health than previously understood.
To reach these conclusions, the research team examined information from several research projects and carefully studied gene activity in brain cells from people with Parkinson’s disease. One protein attracted particular attention. It is called PIAS2. The researchers found much higher levels of this protein in brain cells affected by Parkinson’s disease than in healthy brain tissue.
The scientists believe PIAS2 may contribute to the blockage that prevents damaged mitochondria from being cleared away. If future studies confirm this idea, medicines designed to target this protein could potentially restore the cell’s natural cleaning system. That could help protect brain cells before they are permanently damaged.
Although the findings are exciting, the research is still at an early stage. More laboratory studies and clinical trials will be needed before new treatments become available. However, understanding what drives the disease is an essential first step toward developing therapies that slow or even stop its progression rather than simply treating symptoms.
The researchers also believe the same mitochondrial problem may occur in inherited forms of Parkinson’s disease and perhaps in other related brain disorders. If that proves true, the discovery could have benefits that extend beyond Parkinson’s disease alone.
This research offers fresh hope to millions of patients and their families. By uncovering a hidden biological process that contributes to the disease, scientists are opening new possibilities for treatments that may preserve brain cells, maintain movement, and reduce the risk of dementia.
While more work remains, the discovery represents an important advance in the long search to better understand and eventually defeat Parkinson’s disease.
If you care about Parkinson’s disease, please read studies that Vitamin B may slow down cognitive decline, and Mediterranean diet could help lower risk of Parkinson’s.
For more information about brain health, please see recent studies that blueberry supplements may prevent cognitive decline, and results showing Plant-based diets could protect cognitive health from air pollution.
The study was published in the journal Molecular Psychiatry.
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