Parkinson’s has evolved from being simply a single disease entity to a Parkinson’s syndrome with major focus on other neurotransmitter systems involved besides dopamine which may account for some of the non-motor symptoms such as cognitive disorders, sleep disorders and neurobehavioral disorders like depression, anxiety and apathy amongst others. The cause of the disease still remains unknown but research in this area is very active with new and intriguing findings being reported constantly.
Research studies are also constantly working to improve the treatments for Parkinson's disease. As more information becomes available about the condition and how it progresses, newer therapies to better control the symptoms maybe developed.
Additionally, researchers are trying to identify treatments that might prevent or slow down the degeneration of nerve cells (often called neurodegeneration), and also ways to identify people with Parkinson's before symptoms begin to appear. However, these are only in the very early stages of development.
In the following section, we review some of the current research in the Parkinson’s arena. This is not an exhaustive review, rather an attempt to give you an overview of the different aspects of PD research.
Research related to Causes;
Scientists are looking for the cause of Parkinson’s disease and focusing on search for possible environmental factors (toxins) that may trigger the onset of the disease, and genetic factors that may play a role in PD. In the United States there is now an Athena Parkinson’s diagnostic panel which tests for three genes, namely LRRK-2, Parkin and DJ1 which are implicated in certain forms of Parkinsonism. Some researchers suspect that mitochondria, the power house of the cell may be the final common pathway for onset of neurodegeneration in PD and hence the role of mitochondrial abnormalities leading to oxidative stress is being studied.
Research on Early Detection;
The Michael J. Fox Foundation is funding research into development of early biomarkers for PD. A blood test that can differentiate patients with very early PD from healthy patients would revolutionize diagnosis and treatment of the disease. This would also have implications for early intervention in Parkinson’s disease and for clinical trials of potential neuroprotective therapies.
Research on Surgical treatments;
Deep brain stimulation (DBS) is one of the most effective surgical treatments for PD patients suffering from Levodopa related motor fluctuations. The relatively low incidence of permanent adverse effects and alteration of the natural course of PD suggests a highly favorable benefit to risk ratio. Since neuroprotection is best applied early in the course of the disease when there are more surviving neurons, investigators believe that further investigation of this procedure is warranted. A pilot study is underway to provide data to help design a full scale multicenter trial to investigate the hypothesis that bilateral DBS in the sub thalamic nucleus is a safe and effective treatment to slow the progression of PD.
Research on Drug and other treatments
- New and promising drug therapies continue to be studied for symptomatic control of Parkinson’s disease. Recently US FDA announced the approval of Requip XL (ropinirole extended release tablets) for the treatment of signs and symptoms of Parkinson’s disease. Requip XL is the first and only oral once per day dopamine agonist indicated for Parkinson’s disease. Patients with PD may experience what is commonly known as “off” time when their medication wears off and their symptoms return. Results from a pivotal study showed that adding Requip XL to patient’s existing Levodopa therapy reduced the amount of “off” time experienced by patients with PD by 2.1 hours per day compared to baseline.
- Trancranial magnetic stimulation (TMS) is being studied for its potential to reduce the symptoms of PD. In TMS an insulated coil of wire on the scalp is used to generate a transient electrical current which in turn produces a magnetic field. This method indicates some promise in partially alleviating some of the symptoms of PD, although it is not able to change the course of progression of the disease.
Research on Stem Cell Therapy;
The use of stem cells to regenerate damaged neural tissues in an area of intense interest and experimental studies have been conducted with varying degrees of success, depending on the particular type of stem cells that were employed. This needs to be extensively studied before it can translate into meaningful therapy for patients with Parkinson’s disease.
Parkinson's research has made leaps and bounds in our understanding of the disease. The findings have helped patients across the world manage the disease. Although no cure has been yet found, Parkinson’s disease research continues to make headway
We are grateful to Dr. Shilpa Chitnis for her contributions to the content of this section.