The Importance Of Taurine
Unlike the familiar amino acids, taurine -- or L-taurine, to be
more particular -- is not used as a building block in proteins. But it
is called an "essential" amino acid because the human body, although it
desperately needs it, cannot synthetize it; we must get it from our
foods. But because taurine is not used for proteins, biochemists
classify it as a conditionally essential amino acid.
Adults can produce sulfur-containing taurine from cysteine with the
help of pyridoxine, B6. It is possible that if not enough taurine is
made in the body, especially if cysteine or B6 is deficient, it might
be further required in the diet.
Human milk contains substances called glutamic acid and taurine,
which may play a positive role in the body's functioning. Taurine,
which is present in large amounts in the developing brain of most
species, including the human, may be necessary for optimal nervous
system development. Taurine is the second most abundant free amino acid
in the milk of human and nonhuman primates.
Taurine has been shown to be essential in certain aspects of
mammalian development, and in vitro studies in various species have
demonstrated that low levels of taurine are associated with various
pathological lesions, including cardiomyopathy, retinal degeneration,
and growth retardation, especially if deficiency occurs during
development. Metabolic actions of taurine include: bile acid
conjugation, detoxification, membrane stabilization, osmoregulation,
and modulation of cellular calcium levels. Clinically, taurine has been
used with varying degrees of success in the treatment of a wide variety
of conditions, including: cardiovascular diseases,
hypercholesterolemia, epilepsy and other seizure disorders, macular
degeneration, Alzheimer's disease, hepatic disorders, alcoholism, and
cystic fibrosis.
Taurine comprises over 50 percent of the total free amino acid pool
of the heart. It has a positive inotropic action on cardiac tissue, and
has been shown in some studies to lower blood pressure. In part, the
cardiac effects of taurine are probably due to its ability to protect
the heart from the adverse effects of either excessive or inadequate
calcium ion (Ca2+) levels. The consequence of Ca2+ excess is the
accumulation of intracellular calcium, ultimately leading to cellular
death. Taurine may both directly and indirectly help regulate
intracellular Ca2+ ion levels by modulating the activity of the
voltage-dependent Ca2+ channels, and by regulation of Na+ channels.
Taurine also acts on many other ion channels and transporters.
Therefore, its action can be quite non-specific. When an adequate
amount of taurine is present, calcium-induced myocardial damage is
significantly reduced, perhaps by interaction between taurine and
membrane proteins.
Taurine conjugation of bile acids has a significant effect on the
solubility of cholesterol, increasing its excretion, and administration
of taurine has been shown to reduce serum cholesterol levels in human
subjects. In a single-blind, placebo-controlled study, 22 healthy male
volunteers, aged 18-29 years, were randomly placed in one of two groups
and fed a high fat/high cholesterol diet, designed to raise serum
cholesterol levels, for three weeks. The experimental group received 6
grams of taurine daily. At the end of the test period, the control
group had significantly higher total cholesterol and LDL-cholesterol
levels than the group receiving taurine.
Both plasma and platelet taurine levels have been found to be
depressed in insulin-dependent diabetic patients; however, these levels
were raised to normal with oral taurine supplementation. In addition,
the amount of arachidonic acid needed to induce platelet aggregation
was lower in these patients than in healthy subjects. Taurine
supplementation reversed this effect as well, reducing platelet
aggregation. In vitro experiments demonstrated that taurine reduced
platelet aggregation in diabetic patients in a dose-dependent manner,
while having no effect on the aggregation of platelets from healthy
subjects.
Research in recent years suggests that faulty taurine in metabolism
may be associated with certain kinds of epileptic seizures.
Insufficient quantities of taurine impedes liver function and, in cats,
leads to blindness. Its role in seizures is that taurine acts to
stabilize cell walls so the neurons can fire off normally. Seizures
result from random firing of nerve cells. Taurine used in quantity to
treat epilepsy has only one known side effect, peptic ulcers, which
clear up when taurine is discontinued.
Although it is readily apparent that taurine is important in
conjugating bile acids to form water-soluble bile salts, only a
fraction of available taurine is used for this function. Taurine is
also involved in a number of other crucially important processes,
including calcium ion flux, membrane stabilization, and detoxification.
Some areas of investigation into the clinical uses of taurine have
revealed significant applications for this amino acid: congestive heart
failure, cystic fibrosis, toxic exposure, and hepatic disorders. Other
conditions such as
epilepsy and diabetes will require further research before a clear
rationale for the use of taurine can be developed.
Unlike the familiar amino acids, taurine -- or L-taurine, to be
more particular -- is not used as a building block in proteins. But it
is called an "essential" amino acid because the human body, although it
desperately needs it, cannot synthetize it; we must get it from our
foods. But because taurine is not used for proteins, biochemists
classify it as a conditionally essential amino acid.
Adults can produce sulfur-containing taurine from cysteine with the
help of pyridoxine, B6. It is possible that if not enough taurine is
made in the body, especially if cysteine or B6 is deficient, it might
be further required in the diet.
Human milk contains substances called glutamic acid and taurine,
which may play a positive role in the body's functioning. Taurine,
which is present in large amounts in the developing brain of most
species, including the human, may be necessary for optimal nervous
system development. Taurine is the second most abundant free amino acid
in the milk of human and nonhuman primates.
Taurine has been shown to be essential in certain aspects of
mammalian development, and in vitro studies in various species have
demonstrated that low levels of taurine are associated with various
pathological lesions, including cardiomyopathy, retinal degeneration,
and growth retardation, especially if deficiency occurs during
development. Metabolic actions of taurine include: bile acid
conjugation, detoxification, membrane stabilization, osmoregulation,
and modulation of cellular calcium levels. Clinically, taurine has been
used with varying degrees of success in the treatment of a wide variety
of conditions, including: cardiovascular diseases,
hypercholesterolemia, epilepsy and other seizure disorders, macular
degeneration, Alzheimer's disease, hepatic disorders, alcoholism, and
cystic fibrosis.
Taurine comprises over 50 percent of the total free amino acid pool
of the heart. It has a positive inotropic action on cardiac tissue, and
has been shown in some studies to lower blood pressure. In part, the
cardiac effects of taurine are probably due to its ability to protect
the heart from the adverse effects of either excessive or inadequate
calcium ion (Ca2+) levels. The consequence of Ca2+ excess is the
accumulation of intracellular calcium, ultimately leading to cellular
death. Taurine may both directly and indirectly help regulate
intracellular Ca2+ ion levels by modulating the activity of the
voltage-dependent Ca2+ channels, and by regulation of Na+ channels.
Taurine also acts on many other ion channels and transporters.
Therefore, its action can be quite non-specific. When an adequate
amount of taurine is present, calcium-induced myocardial damage is
significantly reduced, perhaps by interaction between taurine and
membrane proteins.
Taurine conjugation of bile acids has a significant effect on the
solubility of cholesterol, increasing its excretion, and administration
of taurine has been shown to reduce serum cholesterol levels in human
subjects. In a single-blind, placebo-controlled study, 22 healthy male
volunteers, aged 18-29 years, were randomly placed in one of two groups
and fed a high fat/high cholesterol diet, designed to raise serum
cholesterol levels, for three weeks. The experimental group received 6
grams of taurine daily. At the end of the test period, the control
group had significantly higher total cholesterol and LDL-cholesterol
levels than the group receiving taurine.
Both plasma and platelet taurine levels have been found to be
depressed in insulin-dependent diabetic patients; however, these levels
were raised to normal with oral taurine supplementation. In addition,
the amount of arachidonic acid needed to induce platelet aggregation
was lower in these patients than in healthy subjects. Taurine
supplementation reversed this effect as well, reducing platelet
aggregation. In vitro experiments demonstrated that taurine reduced
platelet aggregation in diabetic patients in a dose-dependent manner,
while having no effect on the aggregation of platelets from healthy
subjects.
Research in recent years suggests that faulty taurine in metabolism
may be associated with certain kinds of epileptic seizures.
Insufficient quantities of taurine impedes liver function and, in cats,
leads to blindness. Its role in seizures is that taurine acts to
stabilize cell walls so the neurons can fire off normally. Seizures
result from random firing of nerve cells. Taurine used in quantity to
treat epilepsy has only one known side effect, peptic ulcers, which
clear up when taurine is discontinued.
Although it is readily apparent that taurine is important in
conjugating bile acids to form water-soluble bile salts, only a
fraction of available taurine is used for this function. Taurine is
also involved in a number of other crucially important processes,
including calcium ion flux, membrane stabilization, and detoxification.
Some areas of investigation into the clinical uses of taurine have
revealed significant applications for this amino acid: congestive heart
failure, cystic fibrosis, toxic exposure, and hepatic disorders. Other
conditions such as
epilepsy and diabetes will require further research before a clear
rationale for the use of taurine can be developed.
- Timothy C. Birdsall, ND. Therapeutic applications of taurine. Altern-Med-Rev. 1998 Apr; 3(2): 128-36
- SARWAR GHULAM. Et al. PROTEIN-FREE AMINO ACIDS IN MILKS OF HUMAN, OTHER PRIMATES AND NONPRIMATES. USDA/ARS CHILDREN'S NUTRION
- Jacobsen JG, Smith LH. Biochemistry and physiology of taurine and taurine derivatives. Physiol Rev 1968;48:424-511.
- Nara Y, Yamori Y, Lovenberg W. Effects of dietary taurine on blood
pressures in spontaneously hypertensive rats. Biochem Pharmacol
1978;27:2689-2692. - Satoh H, Sperelakis N. Review of some actions of taurine on ion
channels of cardiac muscle cells and others. Gen Pharmac
1998;30:451-463. - Mizushima S, Nara Y, Sawamura M, Yamori Y. Effects of oral taurine
supplementation on lipids and sympathetic nerve tone. Adv Exp Med Biol
1996;403:615-622. - Reiter, Joel, Epilepsy: A New Approach, Walker and Company, N.Y. 1990, pp172-174.
No comments:
Post a Comment