Gut bacterial tyrosine decarboxylases res... - Cure Parkinson's

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Gut bacterial tyrosine decarboxylases restrict levels of levodopa in the treatment of Parkinson’s disease

LAJ12345 profile image
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nature.com/articles/s41467-...

“Several amino acid decarboxylases have been identified in bacteria. Tyrosine decarboxylase (TDC) genes (tdc) have especially been encoded in the genome of several bacterial species in the genera Lactobacillus and Enterococcus17,18. Though TDC is named for its capacity to decarboxylate L-tyrosine into tyramine, it might also have the ability to decarboxylate levodopa to produce dopamine due to the high similarity of the chemical structures of these substrates. This implies that TDC activity of the gut microbiota might interfere with levodopa/decarboxylase inhibitor availability, thus the treatment of PD patients.”

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LAJ12345
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Oceanflow profile image
Oceanflow

Hi! Now I’m confused - are we to now avoid foods containing tyrosine, or have I got this all backwards? I take 5 Sinemet or more daily….

LAJ12345 profile image
LAJ12345 in reply to Oceanflow

I’m not sure. I think it means those bacteria might be a problem. You need tyrosine at least in food to produce dopamine.

park_bear profile image
park_bear in reply to Oceanflow

This paper is speculative, saying that because these bacterial enzymes affect tyrosine they might also affect levodopa because the two are similar. So no worries about tyrosine consumption.

With that said there is a very important reason to have plenty of tyrosine in your diet. Because levodopa so similar it can accidentally get substituted for tyrosine when your body builds proteins, which makes defective proteins. An abundance of tyrosine minimizes this.

Reference: pubmed.ncbi.nlm.nih.gov/220...

Tyrosine and levodopa structures
LAJ12345 profile image
LAJ12345 in reply to park_bear

I thought it might be also suggesting the bacteria were a problem? So reducing the bacteria would be better rather than reducing the tyrosine that is needed?

pubmed.ncbi.nlm.nih.gov/272...

Berberine to treat E.faecalis.

johntPM profile image
johntPM

Thanks LAJ12345 for pointing us to this paper. For a, perhaps, easier description, please see Simon Stott's posting:

scienceofparkinsons.com/201...

For myself, I see that in the first few years after symptoms are beginning to be seen that levodopa works well for most people labelled with a PD diagnosis. (Indeed, if we limit ourselves to a subset of PwP who respond well to levodopa, then levodopa works for all patients with PD. I know this is a circular argument!)

What then would be the effect, on prescribing and researching, of putting all the research efforts into just focusing on improving the efficacy of levodopa and its helpers (e.g. carbidopa)? Can the honeymoon period be extended? Can a larger, but more intelligent dosing regimen improve dyskinesia and dementia rates?

This is not for DIYing, but has any clinical trial tested PwP on very high doses of levodopa (with carbidopa), perhaps 2000 mg per day.

Increasing the dose is one way to look at this. Decreasing the waste, caused by levodopa metabolism outside of the brain, is another. The paper goes some way to persuading us that the gut is a good place for looking for such mechanisms.

LAJ12345 profile image
LAJ12345 in reply to johntPM

Thanks.

The doctors had hubby on doxycline on and off for years for rosacea and acne. Maybe not a good thing then in the long run.

Recently they put my daughter on it for acne . I told her to avoid it but they talked her into it.

pubmed.ncbi.nlm.nih.gov/272...

nature.com/articles/s41392-...

Berberine for E.faecalis treatment

reedboat2 profile image
reedboat2 in reply to johntPM

Thanks for the SofP link. Very interesting article on the role of gut microbiota in PD and their potential use in treatment.

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