N-γ-(L-Glutamyl)-L-selenomethionine enhances stress resistance and ameliorates aging indicators via the selenoprotein TRXR-1 in Caenorhabditis elegans

Scope: Selenium is an essential trace nutrient for human health. This study investigates the organic form of selenium, N-γ-(L-Glutamyl)-L-selenomethionine (Glu-SeMet), for its effects on aging indicators and stress resistance. The role of the selenoprotein TRXR-1 was also evaluated in Caenorhabditis elegans. Methods and results: Glu-SeMet-treated wild-type N2 worms showed increased survival upon oxidative and thermal stress challenges. However, Glu-SeMet treatment did not extend the lifespan of wild-type N2 C. elegans under normal conditions (p = 0.128 for 0.01 μM and p = 0.799 for 10 μM Glu-SeMet). Under stress conditions, Glu-SeMet significantly increased the survival of wild-type N2 C. elegans, but the phenomenon was absent from trxr-1 null mutant worms. Furthermore, Glu-SeMet treatments significantly ameliorated aging indicators, including body bends, pumping rate, defecation duration, and lipofuscin accumulation in wild-type N2 nematodes. Nevertheless, the ameliorative effects by Glu-SeMet were absent in the trxr-1 null mutant worms. Conclusion: The findings indicate that enhanced stress resistance and improved aging indicators by Glu-SeMet in C. elegans are mediated by the selenoprotein TRXR-1. Glu-SeMet has potential for improving health and also provides new insights into selenium's regulatory mechanisms in intact organisms. ? 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim