Glutathione and cellular thiol-redox system (GSH/Thiol-redox system)

The glutathione and cellular thiol-redox system is a fundamental network of molecules and enzymes responsible for maintaining cellular redox homeostasis and protecting cells from oxidative damage. At its core is glutathione (GSH), a tripeptide that acts as a major antioxidant by neutralizing reactive oxygen species (ROS) and serving as a cofactor for enzymes like glutathione peroxidase (GPX) [Source: NIH/StatPearls]. This system also includes the thioredoxin (Trx) and glutaredoxin (Grx) pathways, which facilitate protein disulfide reduction and regulate various signaling cascades [Source: PubMed - PMID: 28219695]. In many diseases, particularly cancer, this system is upregulated to protect malignant cells from high metabolic stress, making it a prime target for therapeutic inhibition to induce ferroptosis or apoptosis [Source: Nature Reviews Drug Discovery]. Conversely, in neurodegenerative and cardiovascular diseases, the system is often impaired, leading to oxidative stress, where thiol-replenishing agents like N-acetylcysteine are explored for cytoprotection [Source: PubMed - PMID: 30585196]. Drugs targeting this system range from enzyme inhibitors like auranofin to precursors that boost antioxidant capacity, reflecting its dual role as both a target for destruction in oncology and preservation in chronic diseases. The system's complexity involves multiple overlapping pathways, ensuring redundancy in maintaining the cellular thiol pool [Source: Wikipedia - Glutathione]. Therapeutic strategies often focus on specific nodes, such as the xCT cystine/glutamate antiporter or GPX4, to selectively disrupt redox balance in pathological states [Source: PubMed - PMID: 31056237].

Other names

Glutathione redox systemThiol-disulfide exchange systemCellular redox homeostasis systemGSH/GSSG systemThioredoxin-glutathione system

The system is targeted through several mechanisms: inhibition of the rate-limiting enzyme in glutathione synthesis (GCLC) by buthionine sulfoximine; inhibition of thioredoxin reductase by auranofin; direct or indirect inhibition of glutathione peroxidase 4 (GPX4) to induce ferroptosis; and the use of thiol-donors like N-acetylcysteine to replenish glutathione levels.