Antioxidant metalloenzymes

Antioxidant metalloenzymes represent a vital class of enzymes that utilize metal ion cofactors to neutralize reactive oxygen species (ROS) and maintain cellular redox balance. This group primarily includes superoxide dismutases (SODs), which employ copper, zinc, manganese, or iron to disproportionate superoxide radicals; catalase, a heme-iron enzyme that decomposes hydrogen peroxide; and glutathione peroxidases (GPxs), which typically utilize selenium to reduce peroxides [PMID: 29470472, PMID: 22229314]. These enzymes serve as the primary defense mechanism against oxidative stress, which is a major driver of cellular damage to DNA, proteins, and lipids. Pathological depletion or dysfunction of these enzymes is associated with a wide range of conditions, including neurodegenerative diseases like Amyotrophic Lateral Sclerosis (ALS), cardiovascular diseases, and chronic inflammation [PMID: 25470114, PMID: 28853752]. Pharmacological interventions targeting this system include the development of small-molecule mimetics, such as ebselen and mangafodipir, which aim to replicate the catalytic activity of the endogenous enzymes [PMID: 22536924]. However, therapeutic application is challenging due to the need for precise control over ROS levels, as complete suppression can interfere with essential redox signaling pathways.

Other names

Metallo-antioxidant enzymesMetal-dependent antioxidant enzymesAntioxidant metalloproteins

Catalytic neutralization of reactive oxygen species (e.g., superoxide to hydrogen peroxide, hydrogen peroxide to water and oxygen) to prevent oxidative damage to cellular components [PMID: 29470472].