Comment · Wed, April 22, 2015 · Ceretropic
Nurturing Aromatic L-Amino Acid Decarboxylase: The enzyme that makes some of our favorite chemical friends inside us (and why pyritinol is so intense?)--those with more understanding of it welcome
Original post in this thread
Debonaire_Death · 3 points
I was doing some research on the competition between L-Tyrosine and 5-HTP, and I ran across their main point of contention: aromatic L-amino acid decarboxylase, or AAAD. I had never heard about the enzyme before, but it was responsible for making both dopamine and serotonin in our bodies. ~~A short wikipedia read lead me to discovering that this enzyme is also responsible for making a lot of the other active intermediaries in our bodies for these monoamines, as well as PEA and histamine.~~
~~The first insight I got from this fact is that something like Tyrosine needs to be acted on by AAAD multiple times to be converted into dopamine, while L-DOPA only needs a single decarboxylation, which I presume would be less taxing for our AAAD reserves. The same would go for substituting Tryptamine instead of 5-HTP: the enzyme has to do double duty for the former. If my logic is correct, supplementing a chemical further along the pathway for these monoamines would reduce competitive inhibition.~~ EDIT: I appear to be a victim to poor Wikipedia editing: there are other intermediary enzymes involved in the conversio…
What they were answering
Direct reply to the original post — see the thread post above.
u/MisterYouAreSoDumb · Ceretropic
L-Tyrosine gets converted to L-DOPA by tyrosine hydroxylase. Then that L-DOPA gets decarboxylated by AAAD to dopamine. L-Tryptophan gets converted to 5-HTP by tryptophan hydroxylase. Then the 5-HTP also gets decarbolxylated by AAAD to serotonin. So L-Tyrosine is not getting acted upon by AAAD twice. It needs the extra step of tyrosine hydroxylase before AAAD can act on it. Then both L-DOPA and 5-HTP share AAAD to create dopamine and serotonin respectively.
The issue with supplementing further down the line is that you are bypassing the other rate-limiting enzymes, which not only cause the enzymes to down-regulate, but also throws off the balance of neurotransmitters. Also, the amount of binding of each neurotransmitter to its respective receptor is going to affect not only expression of said receptors, but also expression of the the enzymes too.
Pyritinol works because it makes the molecule nonpolar, and allows it past the BBB more efficiently.