Redox control in trypanosomatids, parasitic protozoa with trypanothione-based thiol metabolism

RAC2-P38 MAPK-dependent NADPH oxidase activity is associated with the resistance of quiescent cells to ionizing radiation

“…25 NADPH-dependent glutathione reductase is a member of the FAD-binding disulfide reductase superfamily and the major enzyme responsible for reduction of GSSG in most organisms, which provides a defense system against oxidants. [26][27][28] GSH oxidation also causes stimulation of the hexose monophosphate shunt and increases the production of NADPH. 26 The low consumption of NADPH and low yields of ROS are associated with low expression levels of RACs in G0 cells, which result in a high antioxidant capacity and radioresistance.…”

The Dithiol Glutaredoxins of African Trypanosomes Have Distinct Roles and Are Closely Linked to the Unique Trypanothione Metabolism

“…The monothiol Grxs have been partially characterized, and we could show that 1-C-Grx1 is a mitochondrial protein that forms an iron-sulfur cluster (25,26). Despite the absence of a GR, trypanosomatids contain appreciable concentrations of free GSH (13). Thus, an intriguing question is if in these parasites GSH serves only as a precursor molecule for T(SH) 2 or if it has distinct functions, such as protein (de)glutathionylation or as a reducing agent of Grxs.…”

Protection Against Oxidative Stress and “IGF-I Deficiency Conditions”

“…In cells exposed to high levels of oxidative stress, like red blood cells, up to 10% of the glucose consumption may be directed to the pentose phosphate pathway (PPP) for production of the NADPH needed for this reaction. In the case of erythrocytes, if the PPP is non-functional, then the oxidative stress in the cell will lead to cell lysis and anemia [79].…”