Roger A. Sunde

Roger Sunde

Professor Emeritus of Nutritional Sciences
B.S. 1972, Biochemistry, University of Wisconsin
Ph.D. 1980, Biochemistry, University of Wisconsin

Contact:
sunde@nutrisci.wisc.edu

Principal Research Interest
Selenium biochemistry, transcriptomics, and metabolism from deficiency to toxicity.

Research Summary:

My research has studied: glutathione peroxidase as a biomarker for selenium (Se) status; selenide and serine as precursors for selenocysteine synthesis; Se regulation of selenoprotein mRNA levels; and Se requirements in rats, lambs, mice, turkeys, chickens, C. elegans, and humans. Using techniques ranging from northern blotting to RNAseq, we found that Se-deficiency decreases Gpx1 transcript levels as well as protein and activity, but only decreases a subset of the 24 selenoprotein mRNAs. In contrast, we found that gene expression changes due to high Se are not part of higher animals’ actions to cope with excess/toxic Se (ref 4).

Thus I shifted my focus to using metabolomics to understand tissue accumulation of excess Se. Collaborating with colleagues at IPREM-Pau in France, we used Se-specific inductively-coupled plasma mass spectrometry (ICP-MS) and molecule specific (ESI Orbitrap MS/MS), to show that turkeys and rats accumulate Se as selenosugar (seleno-N-acetyl galactosamine) as both low molecular weight selenometabolites such as glutathione-, cysteine-, and methyl-conjugates of the selenosugar, but also as high molecular weight “selenosugar-decorated proteins” via mixed Se-S bonds (ref 2,5). No selenomethionine is found in turkeys and rats supplemented with selenite; in rats supplemented dietary SeMet, only with toxic SeMet supplementation does liver SeMet become the predominant Se species (ref 3).

Recently, we have used pretreatment without or with β-mercaptoethanol, followed by PAGE and laser-ablation ICP-MS, to show that these selenosugar residues are bound to protein subunits of multiple sizes, and that targeted attachment of selenosugars to a single or limited number of protein subunits does not occur (ref 1).

Representative Publications

  • Bierla K, Szpunar J, Lobinski R, Sunde RA. Use of laser-ablation inductively-coupled mass spectroscopy for analysis of selenosugars bound to proteins, Metallomics 2025;17:mfaf002. https://doi.org/10.1093/mtomcs/mfaf002
  • Bierla K, Szpunar J, Lobinski R, Sunde RA. Effect of graded levels of selenium supplementation as selenite on expression of selenosugars, selenocysteine, and other selenometabolites in rat liver, Metallomics 2023;15:mfad066. https://doi.org/10.1093/mtomcs/mfad066
  • Bierla K, Szpunar J, Lobinski R, Sunde RA. Selenomethionine supplementation and expression of selenosugars, selenocysteine, and other selenometabolites in rat liver, Metallomics 2023;15:mfad067. https://doi.org/10.1093/mtomcs/mfad067
  • Sunde RA. Gene set enrichment analysis of selenium-deficient and high-selenium rat liver transcript expression and comparison with turkey liver expression, J Nutr 2021;151:772-784. https://doi.org/10.1093/jn/nxaa333
  • Katarzyna B, Taylor RM, Szpunar J, Lobinski R, Sunde RA. Identification and determination of selenocysteine, selenosugar, and other selenometabolites in turkey liver, Metallomics 2020;12:758-766. https://doi.org/10.1039/d0mt00040j
  • Taylor RM, Mendoza KM, Abrahante JE, Reed KM, Sunde RA. The hepatic transcriptome of the turkey poult (Meleagris gallopavo) is minimally altered by high inorganic dietary selenium, PLoS One 2020;15:e0232160. https://doi.org/10.1371/journal.pone.0232160
  • Sunde RA, Zemaitis II ET, Blink AB, Lawinger JA. Impact of glutathione peroxidase-1 (Gpx1) genotype on selenoenzyme and transcript expression when repleting selenium-deficient mice, Biol Trace Elem Res 2018;186:174-184. https://doi.org/10.1007/s12011-018-1281-6
  • Sunde RA. Selenium regulation of selenoprotein enzyme activity and transcripts in a pilot study with Founder strains from the Collaborative Cross, PLoS ONE 2018;13:e0191449. https://doi.org/10.1371/journal.pone.0191449
  • Sunde RA, Li JL, Taylor RM. Insights for setting of nutrient requirements, gleaned by comparison of selenium status biomarkers in turkeys and chickens versus rats, mice, and lambs, Adv Nutr 2016;7:1129-1138. https://doi.org/10.3945/an.116.012872
  • Raines AM, Sunde RA. Selenium toxicity but not deficient or super-nutritional selenium status vastly alters the transcriptome in rodents, BMC Genomics 2011;12:26. https://doi.org/10.1186/1471-2164-12-26
  • Sunde RA, Raines AM, Barnes KM, Evenson JK. Selenium status highly-regulates selenoprotein mRNA levels for only a subset of the selenoproteins in the selenoproteome, Biosci Rep 2009;29:329-338. https://doi.org/10.1042/BSR20080146
  • Weiss SL, Sunde RA. Cis-acting elements are required for selenium regulation of glutathione peroxidase-1 mRNA levels, RNA 1998;4:816-827. https://doi.org/10.1017/s1355838298971990
  • Weiss SL, Evenson JK, Thompson KM, Sunde RA. The selenium requirement for glutathione peroxidase mRNA level is half of the selenium requirement for glutathione peroxidase activity in female rats, J Nutr 1996;126:2260-2267. https://doi.org/10.1093/jn/126.9.2260
  • Saedi MS, Smith CG, Frampton J, Chambers I, Harrison PR, Sunde RA. Effect of selenium status on mRNA levels for glutathione peroxidase in rat liver, Biochem Biophys Res Commun 1988 ;153:855-861. https://doi.org/10.1016/s0006-291x(88)81174-4
  • Sunde RA, Evenson JK. Serine incorporation into the selenocysteine moiety of glutathione peroxidase, J Biol Chem 1987;262:933-937. https://doi.org/10.1016/S0021-9258(19)75875-X
  • Sunde RA, Hoekstra WG. Incorporation of selenium from selenite and selenocystine into glutathione peroxidase in the isolated perfused rat liver, Biochem Biophys Res Commun 1980;93:1181-1188. https://doi.org/10.1016/0006-291x(80)90614-2
  • Hafeman DG, Sunde RA, Hoekstra WG. Effect of dietary selenium on erythrocyte and liver glutathione peroxidase in the rat, J Nutr 1974;104:580-587. https://doi.org/10.1093/jn/104.5.580
  • Complete List of Published Work in MyBibliography: https://www.ncbi.nlm.nih.gov/myncbi/roger.sunde.1/bibliography/public/