L-Isoleucine
L-Isoleucine
is an essential amino acid and also categorized as
a “Branched Chain” amino acid. The other branched
chain amino acids are Valine and leucine. These are
referred to as branched chain due to the fact of their
molecular arrangement is marked by branched points.
L- Isoleucine is also identified by the abbreviation
ILE or I and has a weight of 113.16.
Function-
In the body amino acid concentration varies. Number
one is glutamic acid, 2nd is aspartic acid, 3rd is
lysine, the 4th is leucine and the concentration of
isoleucine and valine are shortly after. Although
the structure of the branched chain amino acids (BCAAs)
is similar they have different metabolic routes. The
breakdown of leucine is entirely through fat pathways,
valine is entirely through carbohydrate pathways and
isoleucine is through both.
The
branched chain amino acids (BCAAs) are the major fuel
involved in anabolic reactions and produce significant
energy under situations of stress. The branched chain
group stimulates protein synthesis and decreases catabolism
(cell breakdown). The branched chain amino acids make
up approximately 40% of the total minimum requirement
of daily amino acid intake.
In
disease conditions where there is muscle wasting,
such as Lou Gehrig’s disease (ALS), the branched chain
amino acids are especially useful. In patients with
conditions such as surgery, trauma, fever, starvation
and infections these amino acids are essential for
aid in recovery.
Branched
chain amino acids have shown to enhance muscle metabolism.
They decrease the breakdown of muscle from physical
stress and are beneficial to oxidative metabolism
during exercise. In the brain the branched chain amino
acids (BCAAs) are necessary for the production of
neuropeptides (chemical messengers) and neurotransmitters
which are involved in pain relieving and calming effects.
Like leucine Isoleucine has a positive effect on balancing
blood sugar in conditions such as diabetes and hypoglycemia.
Deficiency- Isoleucine has been found
to be deficient in people suffering from many different
mental and physical disorders. Muscle wasting and
impairment with neurotransmitters and neuropeptides
are associated conditions involved with the metabolism
of these. (Refer to neurotransmitter deficiency.)
A deficiency of isoleucine can lead to symptoms similar
to those of hypoglycemia. In animal studies deficiencies
were found to be accompanied by tremors and twitching
of muscles.
Sources- Dietary sources include
brown rice, beans, meat, nuts, soy flour, and whole
wheat.
Precautions-
There is many inborn errors of amino acid metabolism
(although not commonly seen). The inborn error of
metabolism is ketoaciduria (Maple Urine Disease) in
which keto acids are excreted. Maple syrup urine can
produce convulsions, ataxia and coma in severe cases.
Requirements-
There is no Recommended Dietary Allowances
(RDA) listed. Individual needs may differ due to clinical
conditions, biochemical individuality and absorption.
All sources of nutrients should be consumed in their
most natural state, in the form of a variety of foods
or supplements when necessary. Free form amino acid
supplements are immediately absorbed by the body and
should be consumed with natural occurring cofactors
for best results. Consulting with a physician that
is properly trained in the natural healing sciences
and amino acid therapy may be needed for optimum results.
Written by Jerome
Rerucha D.C.
References-
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amino acids on total parenteral nutrition-induced
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2. Blackburn GL, Moldawer LL, Usui S, Bothe A Jr,
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administration and metabolism during starvation, injury,
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3. Louard RJ, Barrett EJ, Gelfand RA. Effect of infused
branched-chain amino acids on muscle and whole-body
amino acid metabolism in man. Clin Sci (Colch) 1990;79(5):457-466.
4. Blomstrand E, Ek S, Newsholme EA. Influence of
ingesting a solution of branched-chain amino acids
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5. Blomstrand E, Hassmen P, Ek S, et al. Influence
of ingesting a solution of branched-chain amino acids
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6. Freyssenet D, Berthon P, Denis C, et al. Effect
of a 6-week endurance training programme and branched-chain
amino acid supplementation on histomorphometric characteristics
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