Glutathione reductase and peroxidase

Feature

Glutathione Peroxidase

Glutathione Reductase

Function

Catalyzes the reduction of hydrogen
peroxide (H₂O₂) and organic peroxides to water and
alcohol, protecting cells from oxidative damage.

Catalyzes the reduction of oxidized glutathione (GSSG)
to its reduced form (GSH), maintaining cellular
redox balance.

Substrate

Hydrogen peroxide (H₂O₂) or organic
peroxides and reduced glutathione (GSH).

Oxidized glutathione (GSSG) and NADPH.

Cofactor

Selenium

FAD (flavin adenine dinucleotide)

Reaction

2 GSH + H₂O₂ → GSSG + 2 H₂O

GSSG + NADPH + H⁺ → 2 GSH + NADP⁺

Role in
Antioxidant
System

Neutralizes harmful peroxides
to prevent oxidative stress.

Recycles GSH, ensuring its availability
for antioxidant reactions.

Clinical
Relevance

Deficiency can lead to increased
oxidative stress and associated diseases.

Impaired activity can disrupt redox homeostasis,
leading to oxidative stress-related disorders.