Role of the microbiome in PD – webinar notes

Here are some notes I took from today’s Michael J. Fox Foundation ( webinar on the role of the microbiome (gut bacteria) in Parkinson’s.

This was not my favorite MJFF webinar.  Very few practical things came out of the presentation and question-and-answer session.  It was mostly a high level overview of the little bit of research that’s been done on this topic.

Probably the best part was the section on diet.

If you’d like more than the gist of things provided below, you can wait for the recording of the conference to be posted to the MJFF website,  Probably next week.



Robin’s Notes from

The Michael J. Fox Foundation’s webinar
“Gut (Bacteria) Check on Parkinson’s: Role of the Microbiome”
January 19, 2017

Jeff Bronstein MD, PhD
Filip Scheperjans, MD, PhD


Click to access gut_bacteria_january_2017_mjff_webinar_slides.pdf

Presentation and Notes:

* Our intestinal tracts are home to about 100 trillion bacteria (3 lbs. worth).
* This community of microorganisms that calls us home is known as the microbiome.
* The gut microbiome plays a key role in developing and regulating our immune system.
* Gut bacteria may affect functioning of nerves in the gut, which could affect nerves of the brain.

Now talking about the “gut-brain axis.” There seems to be communication both ways.

The gut affects mood.

Does the bacteria release hormones and other chemicals that affect the brain?  Does the bacteria communicate with the neurons in the gut?

1. The gut is an entry point for environmental exposures such as pesticides.
2. Some researchers believe changes seen in the key Parkinson’s protein alpha-synuclein first happen in the gut.
3. Constipation is reported as one of the earliest Parkinson’s symptoms.
4. Slow emptying of the stomach (gastroparesis) is a Parkinson’s symptom and impacts medication absorption/effect.

Constipation is often present 4-5 years before motor symptoms.  Could even be 20 years before motor symptoms.  Why does this happen?

Jeff: No consensus that PD starts in the gut.  This might not be true for everyone.  There is evidence that there is early pathology in the gut.

Filip:  Gastroparesis is especially important in advanced PD given the link to dyskinesia.  Even in early PD, 60% of patients show signs of gastroparesis.  Gastroparesis – slowed emptying of the stomach to the small bowel.

Filip: There hasn’t been a study of the whole gut biome and its effect on PD symptoms.

* People with Parkinson’s may have less of bacteria that protect from environmental toxins and inflammation.
* Gut bacteria levels may be associated with different types of Parkinson’s symptoms, such as gait/balance difficulty.
* Bacteria in the gut may influence medication response.

Filip: Looked at stool samples to determine that those with PD are about 80% low on certain helpful bacteria.  This may affect the mucus layer of the gut which make you more susceptible to environmental toxins.  Other studies have pointed to inflammation.

Jeff: Cause and effect still not clear.  People who are constipated but not PD also have bacteria issues.

Jeff: CalTech study showed that those mice with a bad microbiome have worse motor symptoms.  This contradicts other studies on fatty acids.

Filip: Low-chain fatty acids seem to be reduced in those with PD.

We don’t know yet, but a healthy diet is never a bad idea.
» Studies are capturing data on diet to make connections to Parkinson’s disease.
» We don’t know exactly which probiotics or how much would impact Parkinson’s-associated gut bacteria.
– Probiotics: bacteria found in food and thought to provide health benefits
» A healthy diet (high fiber, low sugar and saturated fat) does alter the microbiome.
» More on how a healthy diet can help manage Parkinson’s through the link in the Resource List.

Jeff: Some movement to pre-biotics.  Good diet most important.  No evidence that probiotics on their own can help.

Filip: To treat gastroparesis, eat smaller portions, many times a day.  Avoid fatty foods.  Perhaps avoid citrus fruits (or things that raise acidity).

Jeff: One study said that people who drink a lot of milk had a higher risk of getting PD.  Perhaps this is a route for pesticides getting into body.

Jeff: Eat organic as much as you can.  Avoid the “dirty dozen” – fruits and vegetables known to have high pesticide residue.  We don’t know the effect of pesticides on the microbiome.

Filip: H. Pylori is related to inflammation of the stomach.  Some studies show this bacteria leads to a risk in PD.  We do know that h. pylori worsens the motor symptoms of PD.  This is attributed to the inflammatory process this bacteria may induce.  It may worsen gastroparesis and reduce absorption of medication.  One study showed that the reduction of this bacteria may be helpful.  Bacteria was reduced due to antibiotics use.  But did the antibiotics also destroy good bacteria?

Video on diet and exercise:

1. Slow progression of Parkinson’s disease and improve health
2. Screen for or track Parkinson’s disease
3. Learn about disease process from the role of bacteria linked to PD
4. Choose people for studies (such as for gait/balance trials)
5. Regulate gut bacteria to optimize medication response

Filip: Someone with constipation is 4 times more likely to develop PD.  We can’t identify which ones will get PD.

A:  Neither MD recommends fecal transplants.