New method maps the dopamine system in Parkinson's patients

February 14, 2018, Karolinska Institutet
Immunohistochemistry for alpha-synuclein showing positive staining (brown) of an intraneural Lewy-body in the Substantia nigra in Parkinson's disease. Credit: Wikipedia

With the aid of a PET camera, researchers from Karolinska Institutet in Sweden have developed a new method for investigating the dopamine system in the brains of patients suffering from Parkinson's disease. The method measures levels of a protein called dopamine transporter and could lead to improved diagnosis of Parkinson's disease and the development of new treatments. The study is published in the scientific journal Movement Disorders.

Dopamine is a substance produced in the brain and is responsible for controlling our movements. The cells that produce are located in an area known as the brainstem, from where dopamine is then secreted into the basal ganglia, an area of the brain that plays an important function in regulating our movements.

In Parkinson's disease, dopamine cells degenerate and their loss is responsible for the motor symptoms that characterise the disorder, such as shaking, slowness of movement and difficulty in walking.

Using a special brain imaging technique known as Positron Emission Tomography (PET), a group of researchers at Karolinska Institutet have measured the levels of the protein DAT that regulates the levels of dopamine in the brain. DAT functions as a biomarker for dopamine cells and is present on the surface of the dopamine cells in the cell bodies, on the and on the nerve endings. By measuring where DAT is found, researchers have been able to map the presence of dopamine cells.

The study was based on 20 patients suffering from mild Parkinsonism and an equal number of healthy individuals. The results showed significantly lower amounts of DAT in in the Parkinson's patients than those not suffering from the disease. However, the amount of DAT remained relatively intact in cell bodies and nerve fibres.

"These results suggest that in the early stages of the disease dopamine are still viable and that, given the correct treatment, it should be possible to restore their function," says Andrea Varrone, senior lecturer in nuclear medicine at Karolinska Institutet's Department of Clinical Neuroscience who led the study.

"The method we have developed is likely to be able to assist in the diagnosis of Parkinson's disease at an earlier stage and predict the development of the disease. DAT can also be used as a biomarker in clinical trials of new medicines and treatment strategies," he continues.

Future studies will examine patients with more advanced Parkinson's, in order to gain a greater understanding of the links between DAT and clinical variables such as and the various stages of the disease.

Explore further: Conversion of brain cells offers hope for Parkinson's patients

More information: Patrik Fazio et al. Nigrostriatal dopamine transporter availability in early Parkinson's disease, Movement Disorders (2018). DOI: 10.1002/mds.27316

Related Stories

Conversion of brain cells offers hope for Parkinson's patients

April 11, 2017
Researchers at Karolinska Institutet have made significant progress in the search for new treatments for Parkinson's disease. By manipulating the gene expression of non-neuronal cells in the brain, they were able to produce ...

Restless sleep may be an early sign of Parkinson's disease

December 6, 2017
Restless sleep could be a sign of a disorder associated with diseases of the brain. Researchers from Aarhus University conducted a case-control study on the condition of the dopamine-producing nerve cells in the brain and ...

Scientific discovery may change treatment of Parkinson's disease

March 22, 2017
When monitoring Parkinson's disease, SPECT imaging of the brain is used for acquiring information on the dopamine activity. A new study conducted in Turku, Finland, shows that the dopamine activity observed in SPECT imaging ...

Impulsivity in Parkinson's disease

October 30, 2017
Dopamine medications are effective in treating the motor symptoms of Parkinson's disease (PD), but dopamine agonists can trigger impulsive-compulsive behaviors (ICBs), such as compulsive gambling, eating or shopping, in a ...

Neurotrophic factor GDNF is an important regulator of dopamine neurons in the brain

February 16, 2017
New research results are expanding our understanding of the physiological role of the glial cell line-derived neurotrophic factor GDNF in the function of the brain's dopamine systems. In an article recently published in the ...

Mechanisms behind sensory deficits in Parkinson's disease

May 18, 2017
Although Parkinson's disease is often associated with motor symptoms such as stiffness, poor balance and trembling, the first symptoms are often sensory and include a reduced sense of touch and smell. In a study on mice, ...

Recommended for you

New transgenic model of Parkinson's illuminates disease biology

October 11, 2018
Parkinson's disease (PD) is a neurodegenerative disorder that presents clinically with abnormal movement and tremors at rest. In the brain, PD is marked by the accumulation of the protein, α-synuclein (αS), into clumps ...

Early Parkinson's patients waiting too long to seek medical evaluation

September 27, 2018
The time between diagnosis and the institution of symptomatic treatment is critical in the effort to find a cure for Parkinson's Disease (PD). A paper published in Nature Partner Journal: Parkinson's Disease notes too many ...

Molecule capable of halting and reverting neurodegeneration caused by Parkinson's disease identified

September 25, 2018
The small SynuClean-D molecule interrupts the formation of the alpha-synuclein amyloid fibres responsible for the onset of Parkinson's disease, and reverts the neurodegeneration caused by the disease. The study, headed by ...

Genomic dark matter activity connects Parkinson's and psychiatric diseases

September 20, 2018
Dopamine neurons are located in the midbrain, but their tendril-like axons can branch far into the higher cortical areas, influencing how we move and how we feel. New genetic evidence has revealed that these specialized cells ...

Gene therapy shown to remove core component of Parkinson's disease

September 14, 2018
An international team led by Rush researcher Jeffrey Kordower, Ph.D., has moved a step closer to developing a treatment to clear brain cells of a protein that is an integral cause of Parkinson's disease. The team published ...

ADHD may increase risk of Parkinson's disease and similar disorders

September 12, 2018
While about 11 percent of children (4-17 years old) nationwide have been diagnosed with attention-deficit hyperactivity disorder (ADHD), the long-term health effects of having ADHD and of common ADHD medications remains understudied. ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.