What is Glutathione? How does Glutathione benefit us?

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What is glutathione?
What are the health benefits of glutathione?

Glutathione (gamma-glutamyl-cysteinyl-glycine) is the most abundant
low-molecular-weight thiol, and the "glutathione /glutathione disulfide" is the
major redox couple in animal cells.

The synthesis of is catalyzed sequentially by gamma-glutamylcysteine
synthetase and glutathione synthetase. Glutathione synthesis is regulated
primarily by gamma-glutamylcysteine synthetase activity. Adequate protein
nutrition is important for the maintenance of glutathione homeostasis.

Thiol groups are kept in a reduced state. In effect, glutathione reduces any
disulfide bond formed within cytoplasmic proteins to cysteines by acting as
an electron donor. In the process, glutathione is converted to its oxidized
form glutathione disulfide (GSSG). Glutathione is found almost exclusively in
its reduced form, since the enzyme that reverts it from its oxidized form,
glutathione reductase, is constitutively active and inducible upon oxidative
stress. Some people use the ratio of reduced glutathione to oxidized
glutathione within cells as a measure of cellular toxicity. [Wikipedia, March
2009]

What are the roles of glutathione in our health?

Glutathione plays important roles in antioxidant defense, nutrient
metabolism, and regulation of cellular events (including gene expression,
DNA and protein synthesis, cell proliferation and apoptosis, signal
transduction, cytokine production and immune response, and protein
glutathionylation).

What is glutathione synthetase deficiency?

Glutathione synthetase deficiency is a disorder that prevents the production
of an important molecule called glutathione. Glutathione helps prevent
damage to cells by neutralizing harmful molecules generated during energy
production. Glutathione also plays a role in processing medications and
cancer-causing compounds (carcinogens), and building DNA, proteins, and
other important cellular components.

Glutathione synthetase deficiency can be classified into three types: mild,
moderate, and severe. Mild glutathione synthetase deficiency usually results
in the destruction of red blood cells (hemolytic anemia). Rarely, affected
people also excrete large amounts of a compound called 5-oxoproline in
their urine (5-oxoprolinuria). This compound builds up when glutathione is
not processed correctly in cells.

Individuals with moderate glutathione synthetase deficiency may experience
symptoms beginning shortly after birth including hemolytic anemia,
5-oxoprolinuria, and elevated acidity in the blood and tissues (metabolic
acidosis).

In addition to the features present in moderate glutathione synthetase
deficiency, individuals affected by the severe form of this disorder may
experience neurological symptoms. These problems may include seizures; a
generalized slowing down of physical reactions, movements, and speech
(psychomotor retardation); intellectual disability; and a loss of coordination
(ataxia). Some people with severe glutathione synthetase deficiency also
develop recurrent bacterial infections.

What diseases are related to glutathione deficiency?

Glutathione deficiency contributes to oxidative stress, which plays a key role
in aging and the pathogenesis of many diseases (including kwashiorkor,
seizure, Alzheimer's disease, Parkinson's disease, liver disease, cystic
fibrosis, sickle cell anemia, HIV, AIDS, cancer, heart attack, stroke, and
diabetes).

How common is glutathione synthetase deficiency?

Glutathione synthetase deficiency is very rare. This disorder has been
described in about 70 people worldwide.

Sources [1] Glutathione synthetase deficiency ghr.nlm.nih.gov March 2009.
[2] Wu G, Fang YZ, Yang S, Lupton JR, Turner ND. Texas A&M University,
Glutathione metabolism and its implications for health. J Nutr. 2004
Mar;134(3):489-92.

MARCH 2009