Parkinson’s disease is a common condition that affects a good number of adults around the world. Up till now, researchers are familiar with the characteristics of the disease but the actual causes of it are still not that well-known.
The findings of a groundbreaking study conducted by scientists at the University of Cambridge in the United Kingdom have shed light on the possible reason for Parkinson’s disease by highlighting the role of calcium in the brain.
The presence of Lewy bodies or accumulation of other toxic proteins inside the brain cells is typically seen in the brain of a patient with Parkinson’s disease. In fact, it is a well-recognized symptom of the health condition.
The deposits in the brain are composed of clusters of alpha-synuclein as well as other proteins that have been folded into an inappropriate shape.
The research held at Cambridge which has been published in the journal Nature Communications has focused on how calcium can impact alpha-synuclein and how it binds to synaptic vesicles.
Synaptic vesicles are tiny compartments located in the nerve terminals. These terminals are responsible for holding the chemical transmitters or what is more widely known as neurotransmitters.
The function of neurotransmitters is to carry and deliver signals or messages between the different brain cells.
According to the co-author of the study Dr. Amberley Stephens, who is a postdoctoral researcher in molecular neuroscience at the University of Cambridge, there is a balance between alpha-synuclein and calcium in the cell.
This balance has to be maintained for the normal functioning of the cell. Dr. Stephens states that too much of the either causes imbalance which may trigger aggregation and may lead to Parkinson’s disease.
Statistically, there are around ten million people suffering from Parkinson’s disease in the world including one million patients in the United States.
In the disease, the patient suffers from progressive destruction of the brain cells that are mandatory for the production of a neurotransmitter known as Dopamine. This neurotransmitter plays a significant role in the control and movement of the body.
This also means that the symptoms of the disease will be worsened upon progression. The patient may have slowness of movement, tremor, rigidity as well as impaired balance and coordination.
Studies on Parkinson’s disease have also shown that the health condition can also affect other brain cells that do not produce dopamine which may explain the signs that are not linked to movements and control.
Abnormal clusters of alpha-synuclein form a major part of the Lewy bodies that are present in the brain of a person with Parkinson’s disease but the normal and usual form of this small protein is needed for many of the brain functions.
The knowledge on how the protein works is, however, limited. According to researchers, the protein interacts with synaptic vesicles for the smooth transportation of molecules from the nerve terminal to the next cell. The underlying mechanism behind this is still not well-known.
Dr. Gabriele Kaminski Schierle, of the Department of Chemical Engineering and Biotechnology at the University of Cambridge, states that alpha-synuclein is a small protein with a little structure and needs to interact with other structures or proteins to perform its functions.
This is what made it hard to study. The team of researchers used super-resolution microscopy and isolated synaptic vesicle to see how alpha-synuclein behaves and works.
It was discovered that the protein binds to vesicles at several points whenever there is a rise in calcium. This may cause the vesicle to cluster. Calcium was seen to affect how the protein behaves with its environment as well as its structure.
The authors concluded that clusters of alpha-synuclein are formed when the balance between the protein and calcium is disturbed. They also suggested that the following may disturb the balance:
- Higher calcium levels in the brain cells at the risk of Parkinson’s
- Age-related effects such as slowing of removal of extra proteins
- Inability to handle calcium in cells vulnerable to Parkinson’s
- Double-production of alpha-synuclein due to gene duplication
It was the first time calcium was seen to affect the alpha-synuclein protein, its structure, and its behavior. The researchers state that a better understanding of the protein in the disease and generally for development of new drugs for Parkinson’s disease.