Paul:
I belive Alpha Keto Glutaric Acid is required in the metabolism of
the amino acids. Humans must make this substance naturally?

[alpha-ketoglutarate (AKG) has the same structure as glutamate (GLU) with the
amine group (NH3) replaced by a double bonded oxygen atom. There are many
reversible reactions where one of them is changed into the other. GLU itself can
be synthesized from AKG and ammonium by a process called reductive animation
which proceeds at the expense of NAD(P)H with a water molecule as a byproduct.
The change from GLU to AKG is involved in many transamidation reactions which
synthesize non essential amino acids with glutamate as the amine group donor
(usually called transamination). The amino acid alanine can be formed in this
manner from pyruvate.
So yes, AKG is made in every cell of the body and is a metabolic entry point of
several amino acids into the citric acid (Krebs) cycle when they are burned as
fuel to generate ATP. --Paul]


Have you read anywhere about supplement levels concerning antiglycation
and levels of toxicity?
Randy

[Here is a study in rodents which found that an oral dose of AKG of 2.0 g/kg
animal weight offered maximum antidotal efficacy against cyanide poisoning, was
non-toxic and therefore could be considered suitable for treatment of cyanide
poisoning.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1\
1746197&dopt=Abstract

However, for anti-glycation purposes I know of no other studies beyond the one
quoted in the previous message (PMID: 9201691). The abstract contains the
statement:

"Mechanistically, the preventive effects appear to be due to (1) competitive
inhibition of glycation by the keto acids and (2) the antioxidant (radical
scavenging) properties of these compounds."

My interpretation of the first part ("competitive inhibition") is that this
means that it would a great deal of AKG to significantly inhibit glycation of
proteins. In addition, mechanism (2) (antioxidant properties) can and already is
being obtained from a multitude of other chemicals. I look upon AKG as merely
one more item in my anti-glycation arsenal.

Finally, the following abstract would suggest that AKG may not be well absorbed
enterally.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1\
2421855&dopt=Abstract

--Paul]