Glutathione peroxidase the body's premiere antioxidant-enzyme

Glutathione peroxidase (GPx) is an enzyme that helps glutathione reduce free radicals such as lipid hydroperoxides and hydrogen peroxide.

GPx uses glutathione as the ultimate electron donor to quench the free radicals to make it harmless.

For example, GPx catalyzes the conversion of hydrogen peroxide by glutathione into water.The reaction is as follows:

reduction with GPx

GSH and GPx both function as antioxidants that help reduce toxic hydrogen peroxide into water.

Because of its role as a catalyst for glutathione, GPx is considered as an antioxidant-enzyme. Meaning, it is an enzyme that has antioxidant properties.

The brain has high GPx activity since it is very vulnerable to free radical damage. The brain, after all, is the body's master controller.

Types of GPx

So far, there are 8 identified types of GPx and are named as GPx1, GPx2, GPx3,and so on up to GPx8.

Glutathione peroxidase 1 (GPx1) is the most abundant type. It is found on the cytoplasm of nearly all cells. GPx 2 is an intestinal and extracellular enzyme, while GPx 3 is extracellular, especially abundant in the plasma.

GPx4 is found in nearly all cells but in lower concentrations.

Did you know that GPx1, GPx2, GPx3 and GPx4 enzymes contain selenium?

Selenium is responsible for destroying lipid-damaging peroxides. It is the Selemiun component of GPX that destroy peroxides, thereby protecting cells and membranes against oxidative damage.

This means Selenium and glutathione work hand in hand in protecting cells from oxidative stress. It's not unusual, therefore, that conditions caused by low selenium are also caused by low glutathione levels.

Deficiencies of Selenium are linked to the following:

Muscular discomfort Cardiomyopathy
Certain forms of arthritis Male Infertility
Poor prostaglandin synthesis Poor skin and hair growth
High blood pressure Cataracts
Cardiac Dysfunction Anemia

GPx is one of the body's important antioxidant enzymes. Since Selenium is its major component, it is crucial for us to have enough Selenium supply in our body.

Food sources of Selenium are:

  • Beef
  • Beef kidney
  • Liver
  • Fish
  • Poultry
  • Eggs
  • Brewers' yeast
  • Brown Rice
  • Cereals
  • Garlic
  • Milk
  • Nuts
  • Whole Wheat Bread

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