Glutathione and Trypanothione (GSH and T(SH)2)

Glutathione (GSH) and Trypanothione [T(SH)2] are essential low-molecular-weight thiols that serve as the primary defense against oxidative stress and maintain intracellular redox balance. Glutathione is a tripeptide (gamma-glutamyl-cysteinyl-glycine) ubiquitous in most aerobic organisms, including humans, where it acts as a cofactor for enzymes like glutathione peroxidase and glutathione S-transferase (PubChem CID 124886). In contrast, Trypanothione is a unique analog found exclusively in kinetoplastid parasites, such as Trypanosoma and Leishmania, consisting of two glutathione molecules linked by a spermidine bridge (Fairlamb & Cerami, 1992). This parasite-specific thiol system is a critical therapeutic target because the parasites lack the glutathione reductase found in humans, relying instead on trypanothione reductase to maintain their thiol pool in a reduced state (Krauth-Siegel & Comini, 2008). Drugs like melarsoprol target this system by forming stable adducts with trypanothione, effectively depleting the parasite's antioxidant capacity and leading to cell death. In human medicine, modulating glutathione levels is a strategy used to overcome chemotherapy resistance in cancer or to treat acetaminophen toxicity using N-acetylcysteine (NIH, 2023). Consequently, the enzymes involved in the synthesis and recycling of GSH and T(SH)2 are major focuses for drug development in both oncology and tropical medicine.

Other names

gamma-L-Glutamyl-L-cysteinylglycineN1,N8-bis(glutathionyl)spermidineGSHT(SH)2Reduced glutathioneReduced trypanothione

Thiol depletion, covalent sequestration of reduced thiols, and inhibition of biosynthetic pathways such as gamma-glutamylcysteine synthetase or polyamine synthesis.