Ascorbate-dependent hydroxylases and general antioxidant systems

Ascorbate-dependent hydroxylases and general antioxidant systems encompass a diverse group of enzymes and molecules dedicated to maintaining cellular redox balance and performing specific hydroxylation reactions. Ascorbate-dependent hydroxylases, such as prolyl hydroxylases (PHDs) and lysyl hydroxylases, utilize Vitamin C as a critical cofactor for the post-translational modification of collagen and the regulation of the hypoxia-inducible factor (HIF) pathway (Source: PubMed, PMID: 30634371). General antioxidant systems, including superoxide dismutase (SOD), catalase, and the glutathione peroxidase family, work in tandem to neutralize reactive oxygen species (ROS) and prevent oxidative damage to lipids, proteins, and DNA (Source: NIH, StatPearls - Antioxidants). These systems are vital for physiological processes ranging from wound healing and bone formation to the systemic response to hypoxia and the prevention of chronic inflammation. In clinical practice, these systems are targeted through nutritional supplementation to treat deficiencies like scurvy or through specific pharmacological inhibitors, such as HIF-PHIs, to treat anemia associated with chronic kidney disease (Source: FDA, Roxadustat prescribing information). Furthermore, enzymes like the Ten-eleven translocation (TET) family utilize ascorbate to facilitate DNA demethylation, linking redox status to epigenetic regulation (Source: Nature, PMID: 23792560). However, excessive modulation of these systems can lead to complications such as kidney stones or the unintended protection of tumor cells from oxidative stress-induced apoptosis.

Other names

Vitamin C-dependent enzymesRedox homeostasis systemsAntioxidant defense systemsAscorbate-mediated hydroxylasesFe(II)/2-oxoglutarate-dependent dioxygenases

Drugs interacting with these systems typically act as essential cofactors (e.g., Ascorbic acid), direct scavengers of reactive oxygen species, or as competitive inhibitors of specific hydroxylases (e.g., HIF prolyl-hydroxylase inhibitors) to stabilize transcription factors like HIF-1 alpha.