Jeff Huseby says; "Is supplemental TMG an adequate source of glycine,
or would it ultimately just provide extra methyl groups? The glycine would then have to buffer?"
I would regard TMG and glycine as completely separate.
And so, they're not entirely separate, there is some interchange, but I think it would get
wildly confusing to try to manage your status of one with the other. So generally speaking, TMG
would donate methyl groups. Chris:
And so glycine is a methyl buffer. It's not like every methyl group that comes
in depletes a molecule of glycine, because if you think about the meaning of a buffer,
a buffer is something that sort of stabilizes, at least in chemistry, and this isn't chemistry, it's
biochemistry. But if you sort of borrow what a buffer means from chemistry, a buffer is going to
keep you in a certain range and prevent you from going to the extremes. So glycine is a biochemical
version of that with methylation, where glycine will take extra methyl groups when they're extra,
and then will release them when they're not there, when you don't have enough. And if you
exceed the capacity of the glycine buffer system, you will lose the methyl groups and the glycine,
but that's after you exceed a certain threshold of being able to hold on to them and release,
hold on and release. Chris:
So it's not the default that one extra methyl group from TMG is going to make
one molecule of glycine get lost, but generally you're going to have... if you
put TMG into the system, you're going to lose methyl groups and you're going to wind up with
probably the dimethylglycine going into the mitochondrion.
And most likely getting those methyl groups stripped away later, and it will generate glycine,
but your glycine is now going to be disproportionately driven into the
compartments and tissues that are using it for methylation buffering. And so, I don't know,
maybe that improves your glycine status, but I'm not so sure about that and I wouldn't rely
on it. So I would just treat them completely differently. Thank you, Jeff, for your question.