Phospholipid hydroperoxide glutathione peroxidase

PHGP, phospholipid hydroperoxide glutathione peroxidase PIH, pyridoxal isonicotinoyl hydrazone PKC, protein kinase C PMA, phorbol... 

O Donnell et al. [70] found that LOX and not cyclooxygenase, cytochrome P-450, NO synthase, NADPH oxidase, xanthine oxidase, ribonucleotide reductase, or mitochondrial respiratory chain is responsible for TNF-a-mediated apoptosis of murine fibrosarcoma cells. 15-LOX activity was found to increase sharply in heart, lung, and vascular tissues of rabbits by hypercholesterolemia [71], Schnurr et al. [72] demonstrated that there is an inverse regulation of 12/15-LOXs and phospholipid hydroperoxide glutathione peroxidases in cells, which balanced the intracellular concentration of oxidized lipids. 

Godeas, C., Sandri, G., and Panfili, E., 1994, Distribution of phospholipid hydroperoxide glutathione peroxidase (PHGPx) in rat testis mitochondria. Biochim. Biophys. Acta, 1191 147-150... 

Yagi, K., Komura, S., Kojima, H., Sun, Q., Nagata, N., Ohishi, N., and Nishikimi, M., 1996, Expression of human phospholipid hydroperoxide glutathione peroxidase gene for protection of host cells from lipid hydroperoxide-mediated injury. Biochem. Biophys. Res. Commun., 219 486-491... 

This selenium-dependent enzyme [EC 1.11.1.9] catalyzes the reaction of two molecules of glutathione with hydrogen peroxide to produce glutathione disulfide and two water molecules. Hydrogen peroxide can be replaced by steroid and lipid hydroperoxides, albeit not as effectively (nevertheless, this enzyme is not identical with phospholipid-hydroperoxide glutathione peroxidase [EC 1.11.1.12]). However, the hydroperoxy products formed by the action of lipoxygenase [EC 1.13.11.12] are not substrates. 

Selenium plays a special role in development and protection of spermatozoa (Chapter 15). Tire selenoprotein phospholipid hydroperoxide glutathione peroxidase (PHGPx Eq. 15-58, Table 15-4) has a high activity in the testis and in spermatids. However, in mature spermatozoa it forms an enzymatically inactive oxidatively crosslinked capsular material around the midpiece of the cell perhaps providing mechanical stability.268 A similar 34-kDa selenoprotein is present in sperm nuclei and may be essential for condensation of DNA.269 Sperm tails contain specialized cytoskele-tal proteins which form "outer dense fibers."270 In contrast to mammalian spermatozoa, nematode sperm move by ameboid motility that depends upon a specialized actin-like molecule.271 Sperm cells are unusually rich in polyamines, most of which are bound to RNA and DNA (Chapter 24). 

Hurst R, Bao Y, Jemth P, Mannervik B, Williamson G. 1998. Phospholipid hydroperoxide glutathione peroxidase activity of human glutathione transferases. Biochem J 332 97-100. 

Imai H. and Nakagawa Y. (2003). Biological significance of phospholipid hydroperoxide glutathione peroxidase (PHGPx, GPx4) in mammalian cells. Free Radical Biol. Med. 34 145-169. 

Nakagawa Y. (2004). Role of mitochondrial phospholipid hydroperoxide glutathione peroxidase (PHGPx) as an antiapoptotic factor. Biol. Pharm. Bull. 27 956-960. 

Nomura, K., Imai H., Koumura T., Kobayashi, T., andNakagawa, Y., 2000, Mitochondrial phospholipid hydroperoxide glutathione peroxidase inhibits the release of cytochrome c from mitochondria by suppressing the peroxidation of cardiolipin in hypoglycaemia-induced apoptosis, Biochem. J. 351 183-193. 

Pushpa-Rekha, T. R., Burdsall, A. L., Oleksa, L. M., Chisoln, G. M., and Driscoll, D. M., 1995, Rat phospholipid-hydroperoxide glutathione peroxidase. cDNA cloning and identification ofmultiple transcription and translation start sites. J. Biol. Chem., 270 26993-26999... 

Roveri, A., Maiorino, M., and Ursini, F., 1994, Enzymatic and immunological measurements of soluble and membrane-bound phospholipid-hydroperoxide glutathione peroxidase. Methods Enzymol. 233 202-212... 

Rao, L University of Wisconsin Genetic characterization of the selenoenzyme phospholipid -hydroperoxide glutathione peroxidase CRISP 2001... 

Ursini F, Maiorino M and Gregolin C (1985) The selenoenzyme phospholipid hydroperoxide glutathione peroxidase. Biochim Biophys Acta 839 62-70. 

Thomas, J.P., Maiorino, M., Ursini, F. and Girotti, A.W. (1990) Protective action of phospholipid hydroperoxide glutathione peroxidase against membrane-damaging lipid peroxidation. In situ reduction of phospholipid and cholesterol hydroperoxides. J. Biol. Chem. 265 454-461. 

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