Redox and antioxidant systems

Redox and antioxidant systems represent a complex network of enzymes, small molecules, and signaling pathways that maintain cellular reduction-oxidation (redox) balance. Key enzymatic components include superoxide dismutase (SOD), catalase, and the glutathione and thioredoxin systems, which work in concert to neutralize reactive oxygen species (ROS) generated during aerobic metabolism [PMID: 28216064]. The system is primarily regulated by the Nrf2-Keap1 signaling axis, which orchestrates the expression of numerous cytoprotective genes in response to oxidative stress [PMID: 25911332]. Dysregulation of these systems is implicated in a wide range of pathologies; for instance, chronic oxidative stress contributes to neurodegeneration and cardiovascular disease, while many cancer cells hijack these systems to survive high-ROS environments and resist therapy [PMID: 24513455]. Therapeutic strategies targeting these systems include Nrf2 activators to enhance defense mechanisms and inhibitors of specific antioxidant enzymes to sensitize tumor cells to oxidative damage. However, the dual role of ROS as both damaging agents and essential signaling molecules presents a significant challenge for drug development, as excessive suppression can disrupt normal cellular communication.

Other names

Antioxidant defense systemRedox signaling pathwaysOxidative stress response systemCellular redox homeostasis network

Modulation of redox-sensitive transcription factors (e.g., Nrf2 activation), direct scavenging of reactive oxygen species, and replenishment of endogenous antioxidant pools like glutathione.