Leucine Intake DOES NOT Increase Levels of HICA in the Blood Stream

Leucine Intake DOES NOT Increase Levels of HICA in the Blood Stream

by Lee Labrada

Lately a lot of pseudo experts have been claiming that you don’t need HICA MAX™ as if you take enough Leucine, your body will be able to get it from there.  However, when you take a look at all of the scientific research, this is simply NOT the case.

The liver contains a very small mitochondrial branched chain amino transferase (BCATm) that can generate a bit of KIC but not HICA from oral leucine administration.

Also, only 6% of BCATm activity is within the liver, the vast majority being in the skeletal muscle, heart, and other organs. Much of the KIC produced is diverted into ATP production as an intermediate in ketogenesis (ketone body production), namely acetoacetate.

The controlling factor for HICA production, rather than KIC, is not understood in the literature at this time, but may relate to cellular conditions (e.g. lactic acid buildup, ATP depletion, IMP, etc).

Here are some research papers of interest:

Source – Nutrients and cell signaling By Krishnamurti Dakshinamurti, Janos
Zempleni; p302
Publisher: CRC Press; 1 edition (April 4, 2005)
Language: English
ISBN-10: 0824722485
ISBN-13: 978-0824722487

And here is more research:

KIC goes up 30%, whereas HICA does not at all after eating. This in humans.

J Nutr. <http://www.ncbi.nlm.nih.gov/pubmed/8360777>  1993
Sep;123(9):1513-21.

Alpha-keto and alpha-hydroxy branched-chain acid interrelationships in
normal humans.

Hoffer LJ
<http://www.ncbi.nlm.nih.gov/pubmed?term=%22Hoffer%20LJ%22%5BAuthor%5D> ,
Taveroff A
<http://www.ncbi.nlm.nih.gov/pubmed?term=%22Taveroff%20A%22%5BAuthor%5D> ,
Robitaille L
<http://www.ncbi.nlm.nih.gov/pubmed?term=%22Robitaille%20L%22%5BAuthor%5D> ,
Mamer OA
<http://www.ncbi.nlm.nih.gov/pubmed?term=%22Mamer%20OA%22%5BAuthor%5D> ,
Reimer ML
<http://www.ncbi.nlm.nih.gov/pubmed?term=%22Reimer%20ML%22%5BAuthor%5D> .

Source

McGill Nutrition and Food Science Centre, Royal Victoria Hospital, Montreal,
Quebec, Canada.

Abstract

Plasma concentrations of the branched-chain amino acids leucine, isoleucine
and valine, and those of leucine’s and isoleucine’s transamination products
alpha-ketoisocaproic acid (KICA) and alpha-keto-beta-methylvaleric acid
(KMVA), respectively, are known to increase after a protein meal or during
extended fasting, but little or no increase in the concentration of valine’s
transamination product, alpha-ketoisovaleric acid (KIVA), has been observed
under these conditions. To determine whether this could be explained by the
conversion of KIVA to its alpha-hydroxy analogue, we measured the plasma
concentrations of KICA, KMVA and KIVA, as well as their alpha-hydroxy
analogues [alpha-hydroxyisocaproic acid (HICA),
alpha-hydroxy-beta-methylvaleric acid (HMVA) and alpha-hydroxyisovaleric
acid (HIVA)], in normal volunteers immediately after a protein meal or
during a 60-h fast. We also determined the oxidoreduction equilibrium
constants for HIVA/KIVA and HICA/KICA and their extent of plasma protein
binding. In subjects in the postabsorptive state, the plasma concentrations
of KICA and KMVA were 100 times those of HICA and HMVA, whereas that of KIVA
was only twice that of HIVA. Shortly after a protein meal, KICA and KMVA
concentrations increased significantly by 30 and 60%, respectively, whereas
that of KIVA decreased by 25% (P < 0.05). HICA, HMVA and HIVA concentrations
did not change
.
During prolonged fasting the plasma concentrations of all
six metabolites increased gradually. The high plasma keto/hydroxy acid
ratios were not related to their K(eq), which favored alpha-hydroxy analogue
formation. The reduction of the branched-chain alpha-keto acids to their
alpha-hydroxy analogues seems to take place too slowly to attain
thermodynamic equilibrium.

(ABSTRACT TRUNCATED AT 250 WORDS)

Conclusion

Again, oral leucine is not an alternative administration option for HICA supplementation.  Do not let the pseudo experts tell you otherwise. The research is very clear. 

Until next time, I am

Lee Labrada
Your Lean Body Coach™

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