What Causes Parkinson’s Disease And Can It Be Prevented?
Exactly what causes Parkinson’s disease (PD) is still not known, but research suggests that it is caused by a combination of genetic and environmental factors. People with certain genetic mutations are at higher risk for developing the disease, however, the vast majority of people with Parkinson’s have no known family history of the disease. It may also be linked to exposure to toxins, such as herbicides and pesticides.
Certain changes in the brain contribute to Parkinson’s disease. It is believed that several years before any physical symptoms appear, chemical imbalances occur in the brain, leading to a gradual loss of nerve cells, specifically, neurons, that produce dopamine, the neurotransmitter responsible for controlling movement and coordination.
As dopamine levels decline, symptoms of Parkinson’s begin to appear. Symptoms of Parkinson’s can include tremors, rigid muscles, slow movements, impaired balance and coordination, and difficulty speaking or swallowing.1
Parkinson’s Disease Is An Autoimmune Disease
New evidence indicates that Parkinson’s is an autoimmune disorder, meaning the body’s own immune system attacks and destroys the healthy nerve cells in the brain.2 As with other autoimmune conditions, a combination of factors is responsible for triggering these conditions, including genetic predisposition, environmental exposures, and microbiome dysbiosis.3
Autoimmune diseases affect more than 23 million people in the United States alone, and while there are many known autoimmune conditions, some of the most common ones include Rheumatoid Arthritis, Lupus, Multiple Sclerosis, Type 1 Diabetes, Celiac Disease, Inflammatory Bowel Disease, Psoriasis, Graves’ Disease, and Hashimoto’s Thyroiditis.
Rheumatoid Arthritis is a chronic inflammatory disorder that affects the joints and other parts of the body, causing pain, fatigue, and stiffness.
Read more about Rheumatoid Arthritis.
Systemic Lupus Erythematosus is an autoimmune disease that can affect any part of the body and cause inflammation. It is also known to damage organs like the kidneys, heart, lungs, and skin.
Read more about Lupus.
Multiple Sclerosis is a progressive neurological disorder that affects the brain and spinal cord. Symptoms include vision problems, muscle weakness, fatigue, and changes in sensation.
Read more about Multiple Sclerosis.
Type 1 Diabetes is a chronic condition that occurs when the immune system attacks and destroys insulin-producing cells in the pancreas. It requires ongoing management to keep blood sugar levels in check.
Read more about Type 1 Diabetes.
Celiac Disease is an inflammatory disorder that is triggered by gluten consumption and affects the digestive system, causing pain and problems with absorption of nutrients.
Read more about Celiac Disease.
Inflammatory Bowel Disease is a group of chronic disorders that cause inflammation in the digestive tract. They can cause abdominal pain, cramping, diarrhea, and fatigue.
Read more about Inflammatory Bowel Disease.
Psoriasis is a skin disorder that is characterized by red, scaly patches of skin that can be itchy and painful. It often appears on the elbows, knees, scalp, lower back, and genitals.
Read more about Psoriasis.
Graves’ Disease is an autoimmune disorder that affects the thyroid gland, causing an overactive thyroid and symptoms like weight loss, fatigue, muscle weakness, and tremors.
Read more about Graves’ Disease.
Hashimoto’s Thyroiditis is another thyroid disorder caused by the immune system attacking the gland. It causes an underactive thyroid and can lead to fatigue, weight gain, and depression.
Read more about Hashimoto’s Thyroiditis.
What Causes Parkinson’s Disease – Genetics
Genetics is one factor behind Parkinson’s disease. Multiple studies have identified specific gene variants that are associated with an increased risk of developing PD. People are more likely to develop PD if they have family members who suffer from the condition.
Recent research has uncovered a strong genetic link between Parkinson’s disease and other autoimmune diseases. The connection is in the form of genetic mutations, which increase an individual’s risk of developing both conditions. Some specific genes that may be linked to both Parkinson’s and other autoimmune conditions include MAPT, LRRK2, GAK, and HLA-DRB5.4
Parkinson’s Disease – Microglia And Neuroinflammation
Neuroinflammation plays an important role in the progression of Parkinson’s Disease. Microglia, the resident immune cells in the central nervous system, are activated in response to changes in the brain environment. Their activation leads to the release of a variety of pro-inflammatory molecules including nitric oxide, cytokines, and chemokines. This leads to a cascade of events resulting in the accumulation of potentially neurotoxic metabolites, and further inflammation that contributes to the progression of PD.5
What Causes Parkinson’s Disease – T Cells
One of the most interesting areas in the study of Parkinson’s Disease is the potential involvement of T cells. T cells are a type of white blood cell that has been found to play an important role in the body’s immune response to illness and infection, but they also appear to be involved in the development and progression of Parkinson’s Disease.
Studies have found that T cells may be involved in the body’s inflammatory response to certain environmental triggers, such as exposure to toxins or other substances. This suggests that if these triggers can be avoided or otherwise managed, it may help reduce the risk of developing Parkinson’s Disease.
Additionally, research has also found that some genetic mutations associated with Parkinson’s Disease can affect T cell function and lead to a more severe form of the disease. Further research is needed to better understand the role T cells may play in the development and progression of Parkinson’s Disease.6
What Causes Parkinson’s Disease – Autoantibodies
Autoantibodies are antibodies directed against the body’s own proteins. In Parkinson’s disease, autoantibodies to certain proteins, including alpha-synuclein and dopamine receptors, are present. It is unclear whether these autoantibodies are a cause or consequence of Parkinson’s. However, their presence may explain why certain individuals are more susceptible to developing the disease. In addition, some researchers believe that autoantibodies could be a potential target for Parkinson’s treatment.7
What Causes Parkinson’s Disease – Environmental Factors
Environmental factors have been linked to Parkinson’s Disease. Exposure to toxins, such as pesticides and herbicides, may increase the risk of developing PD. Additionally, head trauma has been associated with an increased risk of developing this condition.
What Causes Parkinson’s Disease – Pesticides And Herbicides
Certain environmental factors such as exposure to pesticides, herbicides, and other toxins can increase the risk of developing Parkinson’s Disease. Studies have found a link between long-term exposure to pesticide use in farm workers and people with Parkinson’s disease.8 9
What Causes Parkinson’s Disease – Mercury And Arsenic
Mercury exposure has been linked to an increased risk of developing Parkinson’s disease. This is because mercury accumulates in the brain and damages neurons, which can lead to abnormal electrical signals in the brain that cause Parkinson’s symptoms. Furthermore, studies have found that people with higher levels of mercury in their bodies were more likely to develop Parkinson’s than those without it.
Long-term exposure to arsenic can lead to an accumulation of the element in the body, which can damage certain areas of the brain responsible for motor control. This could lead to tremors and other symptoms associated with Parkinson’s. People exposed to high levels of arsenic through drinking water or occupational exposure have been found to be at a higher risk for developing Parkinson’s disease.10 11
What Causes Parkinson’s Disease – Microbiome Dysfunction
Recent research has revealed that an imbalance in the gut microbiome is a contributing factor to Parkinson’s disease. Specifically, studies have found that individuals with Parkinson’s have fewer beneficial bacteria and more pathogenic bacteria in their gastrointestinal tract compared to people without the disorder. Furthermore, researchers have identified particular bacterial species associated with Parkinson’s disease, including several strains of Streptococcus, Clostridium, and Enterococcus.
This microbiome imbalance contributes to inflammation in the body, which may lead to oxidative stress, a state in which toxic molecules are created that can damage cells throughout the body. This damage can eventually cause cell death or malfunction and increase an individual’s risk for Parkinson’s. Additionally, it has been suggested that some of the toxins released by certain types of bacteria may directly affect dopamine-producing neurons in the brain, further increasing an individual’s risk for Parkinson’s.12
What Causes Parkinson’s Disease – Low Vitamin D Levels
Low vitamin D levels have been linked to Parkinson’s disease, and treating low vitamin D levels may help to manage the symptoms of this condition. This is why it is important to get adequate exposure to the sun and consume foods that are high in vitamin D such as salmon, tuna, fortified milk, eggs, and mushrooms.13
Read more about the link between autoimmune conditions and low vitamin D levels.
What Causes Parkinson’s Disease – Vitamin A, E B6, B9, And B12 Deficiency
Vitamin A, E, B6, B9, and B12 deficiencies are associated with Parkinson’s Disease. Vitamin A deficiency can disrupt the normal functioning of dopamine-producing neurons in the brain, leading to the onset of motor symptoms. Vitamin E is essential for protecting cells from damage due to free radicals and may reduce oxidative stress in the brain that is associated with Parkinson’s.
Vitamin B6 helps regulate the production of dopamine, while vitamins B9 and B12 aid in DNA synthesis, helping to restore neuron function. Studies have suggested that supplementing with these vitamins may help slow the progression of Parkinson’s Disease.14
Managing Parkinson’s Disease – Exercise
Exercise is an important factor in managing Parkinson’s disease. Regular physical activity can help reduce symptoms, improve movement and balance, and increase overall quality of life. It is recommended that people with Parkinson’s should aim for at least 150 minutes of moderate-intensity aerobic exercise per week to get the most benefit. Additionally, exercises that specifically target muscle strengthening, balance, coordination, and flexibility are important for helping to preserve movements.15
What Causes Parkinson’s Disease – Diet
While there is no evidence to suggest that specific foods cause or prevent Parkinson’s, certain dietary components are linked to the development and progression of the condition. Studies have shown that a diet rich in antioxidants and anti-inflammatory compounds can help protect against the disease.16
Consumption of foods like seeds, nuts, olive oil, fish, vegetables, and fruit is associated with lower rates of Parkinson’s Disease.17
What Causes Parkinson’s Disease And Can It Be Prevented
Exactly what causes Parkinson’s disease is still up for debate although genetic factors and environmental factors like pesticides, herbicides, heavy metals, and microbiome dysfunction all play a role. Exercising, consuming an organic diet, and taking in adequate vitamins is the best way to prevent this disease.
Read about what causes Alzheimer’s Disease.
References
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3 Ditzel HJ. Human antibodies in cancer and autoimmune disease. Immunol Res. 2000;21(2-3):185-93. doi: 10.1385/IR:21:2-3:185. PMID: 10852116.
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6 Sulzer D, Alcalay RN, Garretti F, Cote L, Kanter E, Agin-Liebes J, Liong C, McMurtrey C, Hildebrand WH, Mao X, Dawson VL, Dawson TM, Oseroff C, Pham J, Sidney J, Dillon MB, Carpenter C, Weiskopf D, Phillips E, Mallal S, Peters B, Frazier A, Lindestam Arlehamn CS, Sette A. T cells from patients with Parkinson’s disease recognize α-synuclein peptides. Nature. 2017 Jun 29;546(7660):656-661. doi: 10.1038/nature22815. Epub 2017 Jun 21. Erratum in: Nature. 2017 Sep 13;549(7671):292. PMID: 28636593; PMCID: PMC5626019.
7 Tansey, M.G., Wallings, R.L., Houser, M.C. et al. Inflammation and immune dysfunction in Parkinson disease. Nat Rev Immunol 22, 657–673 (2022). https://doi.org/10.1038/s41577-022-00684-6
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