There are several theories about what initiates the development of Parkinson’s disease (PD), and inflammation or toxins have been suggested as potential triggers. Research has shown that these factors are most likely secondary to an interaction between genetic and environmental factors.
Very Well Health’s recent entitled “Causes and Risk Factors of Parkinson’s Disease” reports that there’s a link between a decrease in dopamine, brain degeneration and Lewy body accumulation associated with Parkinson’s disease. However, it isn’t clear if one of these problems happens first and causes the others, or if they are all caused by another disease trigger.
Deficiency in Dopamine.
The most direct cause of Parkinson’s disease symptoms is insufficient dopamine, which is a neurotransmitter sending signals to neurons. Dopamine modulates muscle control to help the body produce smooth physical movements. When an individual with PD has a deficit of dopamine, they may experience a resting tremor, muscle rigidity, impaired balance and an overall decrease in physical movement. Dopaminergic medications, such as Sinemet (carbidopa/levodopa) and Mirapex (pramipexole), mimic the action of the deficient dopamine in the body. These medications may be able to relieve symptoms of PD for years. However, these medications don’t prevent the disease itself from worsening—brain degeneration and Lewy body accumulation continue, despite treatment with dopaminergic therapy.
Neurodegeneration.
Another issue noted with Parkinson’s is the loss of neurons in the substantia nigra, a region of the midbrain. The midbrain is part of the brainstem (the lowest part of the brain, connected to the spinal cord). The substantia nigra makes dopamine; this stimulates cells throughout the basal ganglia. The changes in the substantia nigra are frequently visible on brain imaging tests. However, this is not always true. Treatment also doesn’t help slow down degeneration or repair it. Neurodegeration can cause cognitive impairment, which often worsens over time.
Lewy Bodies and Alpha-Synuclein.
Parkinson’s disease is also associated with a buildup of intracellular inclusions inside the neurons, called Lewy bodies, which are made mainly of a protein called alpha-synuclein. They aren’t seen in brain imaging studies but have been detected in research studies that examine the brains of people who had PD and donated their own brains to science for the purpose of research. There is no known treatment or method of removing the Lewy bodies at this time. In PD, Lewy bodies are located in the substantia nigra as well as other areas, including the amygdala and locus coeruleus (which are involved with emotions), the raphe nucleus (which is involved with sleep) and the olfactory nerve (which controls smell). The functions controlled by these regions can be impaired in PD, although the symptoms aren’t as noticeable as the tremors and muscle stiffness. They’re also present in the brains of some people who have Alzheimer’s disease and other types of dementia. They are considered a sign of neurodegeneration.
Help is Available.
National and local resources are available for individuals living with Parkinson’s disease and their loved ones. The National Institute of Neurodisorders and Stroke provides information about risk factors, diagnosis, and treatment. They also spotlight ongoing research. The Parkinson’s Foundation has many helpful resources for National Parkinson’s Awareness Month, and throughout the year. In the Dallas area, we are fortunate to have the Dallas Area Parkinson Society, an essential resource for support groups, exercise programs, and educational classes. The Parkinson’s Voice Project is another wonderful local resource, providing speech therapy and other services supporting individuals living with PD.
If you or someone close to you has been diagnosed with Parkinson’s disease, it is wise to consult with an experienced Elder Law Attorney to ensure you have your estate planning up to date, and specific to the needs that may arise due to your diagnosis. Contact our office today.
Reference: Very Well Health (Nov. 28, 2022) “Causes and Risk Factors of Parkinson’s Disease
