A COMMON GUT MICROBE MAY PLAY A ROLE in Parkinson’s disease development, according to a small study. The bacteria causes aggregation of the alpha-synuclein protein, a central feature in Parkinson’s disease. Today we explore Parksin’s disease and the microbiome.
While the finding is only sometimes actionable, it offers a new avenue of scientific exploration.
Parkinson’s disease is a brain disorder. Unintended (or uncontrollable) movements characterize the condition; for instance, affected individuals may have stiffness, shaking, or challenges with balance and coordination. The symptoms often begin gradually and become progressively worse over time.
“It’s not like I take two pills and then at 10am I take another two. It really depends on what chemicals are brewing in my brain that day” — Actor Michael J. Fox, speaking to CNN in 2010.
What Causes Parkinson’s Disease?
Parkinson’s disease results from nerve cell loss in the brain part known as the substantia nigra.
The neurons in this small part of the brain produce the chemical dopamine. Dopamine is a neurotransmitter that transmits messages between various brain and nervous system parts. This process is important for the control and coordination of body movements.
If the substantia nigra nerve cells (neurons) are damaged, brain dopamine volume drops. With the slow loss of nerve cells, physical movements become abnormal and slow.
Disease symptoms typically only emerge after approximately half of the nerve cell activity in the substantial nigra is gone.
Parkinson’s Disease Symptoms
Parkinson’s disease signs and symptoms vary among individuals. Early in the disease process, symptoms may be mild and unnoticed. Many affected individuals develop symptoms on one body side (and remain worse on that side, even after the symptoms affect both sides of the body).
The Mayo Clinic (USA) offers that selected Parkinson’s disease signs and symptoms may include:
- Tremor. Rhythmic shaking often starts in a limb, often in the hand or fingers. You may rub your thumb and forefinger back and forth, a so-called pill-rolling tremor. The hand may tremble at rest (and decrease when performing tasks).
- Slowed movement (bradykinesia). Over time, the disease may slow movement, making simple tasks challenging and time-consuming. Your steps may become shorter when you walk. It can be challenging to rise from a chair. You may drag or shuffle your feet as you try to walk.
- Rigid muscles. Any body part may have muscle stiffness. The stiff muscles may be painful and limit movement range.
- Impaired posture and balance. Posture can become stooped. Some individuals fall easily or have balance problems.
- Loss of automatic movements. You may experience a decreased ability to do unconscious movements, including blinking, smiling, or swinging your arms when you walk.
- Speech changes. You may speak softly, quickly, slur, or hesitate before talking. Many have monotonic speech.
- Writing changes. It may become hard to write, and your writing may appear small.
Parkinson’s Disease Causes
It remains unknown why Parkinson’s disease-associated nerve cell loss occurs. The condition is likely related to both genetic and environmental factors.
Parkinson’s disease sometimes runs in families, but this phenomenon is unusual. Uncommonly, cases are attributable to specific genetic variants.
Some environmental toxins — including herbicides and pesticides used in farming — may be related, as can industrial pollution. Despite these hypotheses, we do not have high-level evidence of a particular environmental cause.
I recently wrote about one potential environmental toxin:
Parkinson’s disease is the most common type of parkinsonism, but there are also some rarer types where a specific cause can be identified. You can learn more at Parkinson’s UK:
Types of Parkinsonism
Parkinsonism is an umbrella term used to cover a range of conditions that share similar symptoms to Parkinson’s.www.parkinsons.org.uk
Parkinson’s Disease and the Microbiome
Specific strains of Desulfovibrio bacteria are likely to cause Parkinson’s disease. That’s the conclusion of Finnish researchers who recently published their findings online in Frontiers in Cellular and Infection Microbiology.
The new research builds on earlier work by the researchers that showed that Desulfovibrio bacteria were more prevalent in patients with Parkinson’s disease, especially patients with more severe disease (than in healthy individuals).
Desulfovibrio is a gram-negative bacterium commonly found in aquatic environments in which organic material levels are elevated and in saturated soils.
For a recent study, the University of Helsinki scientists searched for Desulfovibrio species in fecal samples from 10 patients with Parkinson’s disease and their healthy spouses.
Scientists fed isolated Desulfovibrio strains to a strain of Caenorhabditis elegans roundworms that expressed human alpha-synuclein protein (a key feature in the pathology of Parkinson’s disease) fused with a yellow fluorescent protein.
Worms fed Desulfovibrio bacteria from patients with PD had significantly more and larger alpha-syn aggregates than worms fed Desulfovibrio bacteria from healthy individuals or worms fed different bacteria (Escherichia coli) strains.
Worms fed Desulfovibrio strains from patients with Parkinson’s disease died in significantly higher quantities than worms fed E. coli bacteria.
Key points — Parkinson’s Disease and the Microbiome?
Question. Could Common Gut Microbe Play a Role in Parkinson’s Disease?
Findings. Specific strains of Desulfovibrio bacteria are likely to cause Parkinson’s disease.
Meaning. Desulfovibrio bacteria may play a pathogenic role in Parkinson’s disease, given they induce alpha-syn aggregation in large numbers. We may need to screen for (and remove in a target fashion) harmful Desulfovibrio bacteria if the connection to PD is confirmed.
This study is early research, uses a non-vertebrate animal model, and has small participant numbers. There are no clinical implications currently. Many of us have this bacteria in our gut and do not get PD. Our understanding of the gut microbiome is early.
We don’t have proven ways to prevent Parkinson’s disease. Some research hints that regular aerobic exercise may lower risk. Other studies suggest that consumers of caffeine (coffee, black and green tea, and cola, for example) have a lower risk of PD. Of course, the association does not establish a causal relationship.
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The information I provided in this blog is for educational purposes only and does not substitute for professional medical advice. Please consult a medical professional or healthcare provider for medical advice, diagnoses, or treatment. I am not liable for risks or issues associated with using or acting upon the information in this blog.
The Magnus Ehrnrooth Foundation and the Jane and Aatos Erkko Foundation supported the Finnish study. The study authors disclosed no relevant financial relationships.
Thank you for reading “Parkinson’s and Microbiome.”
