Biosynthesis glutathione

As noted above, the X-ray sensitization of cells using MGd has been investigated extensively and appears to operate at least in part in an oxygen dependent manner, with cytotoxic activity that is substantially enhanced upon the addition of ascorbate to the media [69], The cytotoxic activity of MGd can also be enhanced with L-buthionine-S,R-sulfoximine (BSO), an irreversible inhibitor of an enzyme involved in glutathione biosynthesis (y-glutamylcysteine synthetase), that serves to suppress the synthesis of ROS-protective glutathione. Presumably, this activity is responsible for the in vitro radiation enhancing effect of BSO [66,71],... 

Male BALB/c mice exposed to ozone (1.2 mg m 10 hr per day) showed decreased TAC of blood serum (by 26% on day 5) (F7). Oxidant stress in vivo elicited by injections of L-buthionine sulfoximine (inhibitor of glutathione biosynthesis), hydroquinone, and triethylenetetraamine reduced TAC of rat blood plasma (LI). 

Ormstad, K., D.P. Jones, and S. Orrenius. Characteristics of glutathione biosynthesis by freshly isolated rat kidney cells. J. Biol. Chem. 225 175-181, 1980. 

Kavanaugh, T. J. University of Washington Glutathione biosynthesis as a biomarker of toxic exposure NIEHS... 

Blocks cellular resistance to chemotherapy by inhibiting y-glutamylcysteine synthetase, a key enzyme in glutathione biosynthesis. 

Vargas MR, Pehar M, Cassina P, Beckman JS, Barbeito L (2006) Increased glutathione biosynthesis by Nrf2 activation in astrocytes prevents p75NTR-dependent motor neuron apoptosis. J Neurochem 97 687-696... 

Figure 19.3 Sortinl-induced phenotypes resemble those of the glutathione biosynthesis inhibitor BSO. (a-c) Both Sortin 1 (b) and BSO (c) inhibit root hair elongation compared with the control (a), (d-f) Fluorescence accumulation in neutral red staining bodies in untreated (d), Sortin 1-treated (e), or BSO-treated (f) seedlings. The seedlings were grown under AlC conditions and stained with Naringenin. The samples were excited with a 543 nm laser line and the fluorescence was detected in the 565-620nm range, (g-i) Both Sortini...

Glutamine is synthesized in pigeon liver homogenates from glutamic acid and ammonia. The reaction requires ATP and a specific enzyme, glutamine synthetase. ADP is formed and inorganic phosphate is released in the reaction. The mechanism of the reaction is similar to that involved in glutathione biosynthesis. 

Shih, A.Y., Johnson, D.A., Wong, G., Kraft, A.D., Jiang, L., Erb, H., Johnson, J.A., et al. 2003. Coordinate Regulation of Glutathione Biosynthesis and Release by Nrl2-Expressing Glia Potently Protects Neurons from Oxidative Stress, 23(8), 3394-3406. 

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