Figure 3.

Glutathione pathway and antioxidative stress. Glutathione is synthesized by three substances glutamate, cysteine, and glycine. Glutathione can eliminate ROS and act as an electron donor for GSH-Px to reduce peroxides. TBHQ activates Nrf2, and Nrf2 positively regulates GST. GST is a ROS detoxification enzyme that eliminates ROS. At the same time, Nrf2 promotes the expression of GCL. GCL is the rate-limiting enzyme for glutathione synthesis. Nrf2 can also regulate GSH-Px and GR, which coordinate the regulation of glutathione regeneration. ROS is also involved in the oxidation of thiols to disulfides, which can be reversed by glutathione. TBHQ: tert-butyl hydroquinone; Nrf2: nuclear factor E2 related factor 2; GCL: glutamate-cysteine ligase; GSH-Px: glutathione peroxidase; GR: glutathione reductase; GST: glutathione S-transferase.