Posted by Larry Hoover on August 19, 2003, at 20:03:48
In reply to Re: TMG » Larry Hoover, posted by andys on August 19, 2003, at 16:48:53
> Larry,
> You've mentioned TMG before, and I even bought some, but haven't taken it yet, because I'm having trouble getting a grasp on just what it does. (I'm taking tyrosine and phenylalanine, in the hopes of increasing the catecholemines).
> Thanks,
> AndyThe reason I keep mentioning TMG is because it provides an alternative mechanism for the recycling of methionine from homocysteine, and thereby promotes natural (i.e. your body's production of...) SAMe.
Here's the simplified cycle.....
You eat protein containing the amino acid methionine (which is rather unique, in that it contains a sulphur atom). The methionine enters the liver, where it has adenosine attached to it at the sulphur atom position, yielding S-adenosyl methionine (SAMe). The S-adenosyl just means that adenosine has been attached at the sulphur position. SAMe is the universal methyl-donor. Methyl donation is sometimes called "one-carbon metabolism" because it involves the transfer of a CH3- group from one molecule to another. Anyway, methylation is a critical step in neurotransmitter synthesis, and DNA activation/transcription, and all sorts of stuff.
Later on, the demethylated (used) SAMe loses the adenosine group, and you're left with homocysteine (methionine minus a methyl group is called homocysteine). Homocysteine can be converted back to methionine again, if you've got enough folate and vitamin B-12 (which becomes a methyl donor to homocysteine), but for many depressives, this recycling process just doesn't work right. Homocysteine accumulates, and starts to damage the artery walls (leading to heart disease and other nasties), and also contributes to a methionine deficit (and, thereby, a SAMe deficit).
This is where TMG (betaine) enters the picture. There's another way to remethylate homocysteine back to methionine, and that's via the liver enzyme called betaine-homocysteine methyltransferase. Trimethylglycine gives up a methyl group to homocysteine, and you get dimethylglycine and methionine. BTW, the dimethylglycine goes on to do other good things, but you get your homocysteine levels to fall and your methionine levels to rise without depending on a mechanism that isn't working right (the folate/B-12 process).
Hope that wasn't too long-winded.
Lar
P.S. About dose....
Take it in the morning (I find it to be very activating). Maybe one gram (1,000 mg)/day to start. If you find any adverse events, like insomnia, you should find that temporarily stopping the supplement will correct that fairly quickly. I can't take it every day, but I know some people who do. I think it's a very individual thing, to work out a tolerable dose.
poster:Larry Hoover
thread:246486
URL: http://www.dr-bob.org/babble/20030818/msgs/252303.html