S-Acetyl Glutathione Supplement - Antioxidant Glutathione for Immune Health

S-Acetyl Glutathione is a dietary supplement contained reduced glutathione in an acetylated form. This is an innovative form which protects the glutathione from oxidation in the gut, thus maximising its bioavailability and enabling it to pass effectively into the body’s cells.

What is reduced glutathione?

Glutathione is composed of 3 peptides : glutamic acid, cysteine and glycine. It is found at relatively high concentrations in every cell in the body: unlike vitamins, glutathione is synthesised naturally in our cells.

Production declines with age, however, sometimes to the point where levels are too low to properly protect the body.

What is oxidative stress?

Oxygen is essential for life as it helps produce energy in the form of ATP. However, the act of doing so has a downside: it involves the continuous, insidious production of toxic molecules called free radicals or reactive oxygen species (ROS). The body has learnt how to defend itself from these wayward molecules by producing endogenous antioxidants, and by drawing on protective compounds provided by the diet, such as vitamins C and E. Under normal physiological conditions, a balance exists between pro-oxidant ROS and antioxidants which, on the whole, prevents any damage.

When the balance tips in favour of the toxic molecules, however, this referred to as oxidative stress. Such an imbalance can be the result of several factors: stress-induced over-production of free radicals, a lack of exogenous antioxidants in the diet, a failure of internal defence systems, or increased exposure to reactive species (through smoking, alcohol, pollution …)… If it persists, oxidative stress can dramatically affect the body’s principal constituents – cells, fatty acids, proteins (such as DNA), sugars – contributing to the development of chronic health problems (1-2).

What are the benefits of supplementing with acetylated reduced glutathione (S-acetyl glutathione)?

Once glutathione molecules reach the gut, they are surrounded by enzymes called gamma-glutamyl transpeptidases, which convert them into relatively ineffective compounds. Some glutathione molecules escape this fate: they manage to cross the intestinal barrier before the enzymes have had a chance to oxidise them, entering the bloodstream in full operational mode. However, the percentage of these molecules is low, such that large amounts of glutathione need to be ingested in order for supplementation to have any meaningful effect.

One way of ensuring the glutathione remains effective is to bind it to an acetyl group which prevents it from being oxidised by gut enzymes. The acetylated glutathione is able to cross the intestinal barrier and enter cells, before cytoplasmic thiosterases cause it to lose its acetyl group.

It is one of the most effective solutions for increasing serum glutathione levels, along with perlingual administration (applied to the tongue) (perlingual glutathione reaches the bloodstream without passing through the gut, thus avoiding the path of gamma-glutamyl transpeptidases).

Why is the brain more vulnerable to oxidative stress?

There are several reasons why the brain is particularly susceptible to oxidative stress:

1. the brain contains large amounts of unsaturated fatty acids which are highly prone to oxidation and potentially harmful to neighbouring cells;
2. despite representing just 2% of body mass, brain cells consume more than 20% of all the oxygen used by the body; significant numbers of reactive oxygen species are thus generated in the brain;
3. the brain is rich in iron, which while essential for DNA synthesis, is also involved in lipid peroxidation;
4. there are fewer antioxidant enzymes such as endogenous glutathione in the brain than in other organs.

All this is exacerbated by advancing age, which it’s clear, contributes to the development of neurodegenerative diseases.

Is reduced glutathione able to reach the brain?

The blood-brain barrier makes it difficult for reduced glutathione to reach brain cells (3). However, natural glutathione synthesis in these cells relies on the recycling of its constituents, and as a consequence, the increase in glutathione circulating in the blood can still support this process.

Which other supplements can be taken alongside reduced glutathione?

A number of other dietary supplements can help boost the effects of glutathione:

• Vitamin C, which helps fight oxidative stress;
• Vitamin E , a powerful antioxidant which helps protect cells ;
• Flavonoids , a group of more than 6000 natural compounds able to exert a multitude of biological activities;
• Zinc, an indirect antioxidant, which acts as a stabiliser of superoxide dismutase;
• Superoxide dismutase itself, as an essential component in the mechanism of free radical elimination.

1. Grune, T., T. Reinheckel, M. Joshi and K. J. Davies (1995). "Proteolysis in cultured liver epithelial cells during oxidative stress. Role of the multicatalytic proteinase complex, proteasome." J Biol Chem 270(5): 2344-51
2. Hensley, K., N. Hall, R. Subramaniam, P. Cole, M. Harris, M. Aksenov, M. Aksenova, S. P. Gabbita, J. F. Wu, J. M. Carney and et al. (1995). "Brain regional correspondence between Alzheimer's disease histopathology and biomarkers of protein oxidation." J Neurochem 65(5): 2146-56.
3. Schulz et al, Glutathione, oxidative stress and neurodegeneration, Eur J Biochem 267 (16):4904-11, 2000