Microorganisms in the Digestive Tract Could Be Linked to Parkinson's Disease: Possible Microbe-Targeted Treatment Approach
New research is shedding light on the role of the gut microbiome in Parkinson's disease (PD), a neurodegenerative disorder affecting millions worldwide. The current scientific evidence strongly supports a link between the gut microbiome and PD development and progression.
Gut Dysbiosis and PD
People with PD often exhibit gut dysbiosis, characterized by an imbalance in gut bacteria. This imbalance is marked by reduced levels of beneficial bacteria, such as Bifidobacterium, Lactobacillus, and Akkermansia, and increased levels of pro-inflammatory bacteria. This microbial imbalance correlates with dietary quality and symptoms.
Short-Chain Fatty Acids and PD
Beneficial gut bacteria produce short-chain fatty acids (SCFAs), which have anti-inflammatory effects, strengthen the intestinal barrier, and may reduce inflammation in the central nervous system. This could potentially slow PD progression.
Gastrointestinal Symptoms and PD
Gastrointestinal symptoms, such as constipation, gastroparesis, and bloating, frequently precede motor symptoms of PD, indicating early gut involvement.
Alpha-Synuclein Aggregation and PD
The aggregation of misfolded alpha-synuclein, a hallmark of PD pathology, has been detected in enteric neurons of the gut before brain involvement. This supports the theory that PD pathology starts in the gut and spreads to the brain via the vagus nerve (Braak’s hypothesis).
Animal Studies and PD
Animal studies show a causal relationship between the gut microbiome and PD. Fecal microbiota transplantation from PD patients worsens motor symptoms and neuroinflammation in mice. Conversely, manipulating gut microbiota through antibiotics or SCFA supplementation modulates PD-like symptoms and neurodegeneration in animal models.
Implications for PD Management
Some PD medications may exert part of their beneficial effects by improving gut microbiota balance. This further links gut health and disease management.
The evidence suggests that gut microbiome alterations contribute to PD pathogenesis and progression by promoting intestinal inflammation, disrupting the gut barrier, enhancing pathological protein aggregation, and influencing brain neuroinflammation and neurodegeneration.
This new understanding opens potential avenues for dietary interventions, microbiome-targeted therapies, and early diagnosis based on gut health markers. The theory that PD starts in the gut before spreading to the brain suggests that early microbiome interventions could alter disease trajectory.
Research increasingly supports a pivotal role for the gut microbiome in PD pathogenesis. Anti-inflammatory diets rich in fiber and antioxidants may support a healthy gut microbiome and reduce PD-associated gut inflammation. Customized probiotic formulations and dietary fibers are being tested to improve gut barrier function and modulate the immune system.
Fecal Microbiota Transplantation (FMT) is being tested in early-stage clinical trials for its potential to slow disease progression in Parkinson's patients. Modifying the microbiome holds promise for treating or preventing PD by addressing underlying causes in the gut. Microbiome-based therapies offer promising avenues to treat or even prevent PD by targeting root causes in the gut. The gut-brain axis is a focus of research in PD, highlighting how microbial communities influence neurodegeneration.
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Science indicates a link between the gut microbiome and medical-conditions such as Parkinson's disease (PD), where a role for short-chain fatty acids (SCFAs) in slowing PD progression is suggested due to their anti-inflammatory effects and potential influence on brain neuroinflammation and neurodegeneration.
In PD, alterations to the gut microbiome contribute to pathogenesis and progression by promoting intestinal inflammation, disrupting the gut barrier, enhancing pathological protein aggregation, and influencing brain neuroinflammation and neurodegeneration. Health-and-wellness interventions like anti-inflammatory diets rich in fiber and antioxidants may support a healthy gut microbiome and reduce PD-associated gut inflammation, offering potential avenues for early diagnosis and treatment.
