Abstract
Selenium (Se) is an essential trace element in animals and human, however, excess Se intake can result in adverse health effects. Se supplementation increased glutathione peroxidase (GSH-Px) and thioredoxin reductase (TR) expressions in Se-deficient rats. However, little information is available on the relationship between Se overexposure on GSH-Px and TR mRNA levels and activities. In this study, the effects of Se overexposure on GSH-Px and TR mRNA levels and activities were investigated by reverse transcription-polymerase chain reaction (RT-PCR) and activity assay. Experimental groups of male Wistar rats were injected intraperitoneally (ip) with sodium selenite at doses of 20, 40, and 80 µg Se/kg/d for 15 d, respectively. Se levels were elevated dose-dependently in rat liver, kidney, and testis tissues. GSH-Px mRNA levels and activities in the liver and testis for rats injected with 20 µg Se/kg/d were increased significantly as compared with those in the control group. However, intraperitoneal injection of 40 and 80 µg Se/kg/d dramatically decreased GSH-Px mRNA expression and activity in liver and testis. The changes of TR mRNA level and activity in the liver and kidney were similar to those of GSH-Px in the liver and testis when supplemented with 40 and 80 µg Se/kg/d. There were no significant effects of Se status on kidney GSH-Px and testis TR expressions. The results suggested that Se overexposure had an adverse effect on GSH-Px and TR mRNA levels and activities, and there could be tissue differences in the regulation of selenoprotein levels.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R. F. Burk, Biological activity of selenium, Annu. Rev. Nutr. 3, 53–70 (1983).
K. Takahashi and H. J. Cohen, Selenium dependent glutathione peroxidase protein and activity: immunological investigation on cellular enzyme, Arch. Biochem. Biophys. 256, 677–686 (1986).
F. Ursini, M. Maiorino, and C. Gregolin, The selenoenzyme phospholipid hydroperoxidase glutathione peroxidase, Biochem. Biophys. Acta. 839, 62–70 (1985).
D. Behne, A. Kyriakopoulos, H. Meinhold, and J. Kohrle, Identification of type I iodothyronine 5′-deiodinase as a selenoenzyme, Biochem. Biophys. Res. Commun. 173, 1143–1149 (1990).
J. C. Davey, K. B. Schneider, M. J. Schneider, D. L. St. Germain, and V. A. Galton, Cloning of a cDNA for the type II iodothyronine deiodinase, J. Biol. Chem. 270, 26,786–26,789 (1995).
W. Croteau, S. L. Whittemore, M. J. Schneider, and D. L. St. Germain, Cloning of a cDNA for a mammalian type III iodothyronine deiodinase, J. Biol. Chem. 270, 16,569–16,575 (1995).
D. Mustacich and G. Powis, Thioredoxin reductase, Biochem. J. 346, 1–8 (2000).
J. G. Yang, J. Morrison-Plummer, and R. F. Burk, Pruification and quantitation of a rat plasma selenoprotein distinct from glutathione peroxidase using monoclonal antibodies, J. Biol. Chem. 261, 13,372–13,375 (1987).
S. C. Vendeland, M. A. Beilstein, C. L. Chen, O. N. Jensen, E. Barofsky, and P. D. Whanger, Purification and properties of selenoprotein W from rat muscle, J. Biol. Chem. 268, 17,103–17,107 (1993).
I. I. Sics, Glutathione and its role in cellular functions, Free. Radical Res. 25, 57–74 (1996).
A. Holmgren, Thioredoxin and glutathione system, J. Biol. Chem. 264, 13,963–13,966 (1989).
K. B. Hadley and R. A. Sunde, Selenium regulation of thioredoxin reductase activity and mRNA levels in rat liver, J. Nutr. Biochem. 12, 693–702 (2001).
National Research Council, Guide for the Care and Use of Laboratory Animals, National Academy Press, Washington, DC (1996).
P. G. Hafeman, R. A. Sunde, and W. G. Hoekstra, Effect of dietary selenium on erythrocyte and liver glutathione peroxidase in the rat, J. Nutr. 104, 580–587 (1974).
J. E. Oblong, P. Y. Gasdaska, K. Sherrill, and G. Powis, Purification of human thioredoxin reductase: properities and characterization by absorption and circular dichroism spectroscopy, Biochemistry 32, 7271–7277 (1993).
M. Bradford, A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein dye binding, Anal. Chem. 72, 248–254 (1976).
J. H. Watkinson, Fluorimetric determination of selenium in biological material with 2, 3-diaminomaphthalene, Anal. Chem. 38, 92–97 (1966).
A. C. Griffin, Role of selenium in the chemoprevention of cancer, Adv. Cancer Res. 29, 419–430 (1979).
Z. Zhu, M. Kimura, Y. Itokawa, T. Aoki, J. A. Takahashi, S. Nakatsu, et al., Apoptosis induced by selenium in human glioma cell lines, Biol. Trace Element Res. 54, 123–134 (1996).
C. Chen, B. Chen, X. Yang, J. Zhou, and H. Xu, Study on the relationship of reactive oxygen species and bilogical dose-response curve of selenium, Trace Element Electrolytes 14, 197–201 (1997).
Y. Seko, Y. Saito, J. Kitahara, and N. Imura, Active oxygen generation by the reaction of selenite with reduced glutathione in vitro, in Selenium in Biology and Medicien, A. Wendel, ed., Springer-Verlag, Berlin, pp. 70–73 (1989).
Y. Seko, J. Kitahar, H. Utsumi, N. Hamada, and N. Imura, Selenite and glutathione caused chemiluminescence in the presence of luminol indicating an active oxygen generation, Proceedings of the Fifth International Symposium on Selenite in Biology and Medicine. p. 108 (1992).
M. P. Rana, R. Ghosh, and M. Chatterjee, Changes in tissue levels of glutathione, extent of lipid peroxidation and activity of glutathione peroxidase in transplantable murine lymphoma, Oncology 51, 25–29 (1994).
L. Tallandini, R. Cecchi, S. D. Boni, S. Galassini, G. Ghermandi, N. Q. Liu, et al., Toxic levels of selenium in enzymes and selenium uptake of a marine fish, Biol. Trace Element Res. 51, 97–106 (1996).
G. Q. Yang, Research on selenium related problems in human health in China, Proceedings of the Third International Symposium on Selenium in Biology and Medicine. p. 9–32 (1987).
R. Yanardag, S. Bolkent, and A. Kizir, Protective effects of DL-α-tocopherol acetate and sodium selenate on the liver of rats exposed to gamma radiation, Biol. Trace Element Res. 83, 263–273 (2001).
R. A. Sunde, Molecular biology of selenoprotein, Ann. Rev. Nutr. 10, 451–474 (1990).
G. Bermano, F. Nicol, J. A. Dyer, R. A. Sunde, G. J. Beckett, J. R. Arthur, et al., Tissue-specific regulation of selenoenzyme gene expression during selenium deficiency in rats, Biochem. J. 311, 425–430 (1995).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Gan, L., Liu, Q., Xu, HB. et al. Effects of selenium overexposure on glutathione peroxidase and thioredoxin reductase gene expressions and activities. Biol Trace Elem Res 89, 165–175 (2002). https://doi.org/10.1385/BTER:89:2:165
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1385/BTER:89:2:165