2025
Inorg Chem. 2025 May 26;64(20):9961-9983. doi: 10.1021/acs.inorgchem.5c00323. Epub 2025 May 13.
Selenium Distribution and Speciation in Tissues from Rats Administered with Non-Native Selenotrisulfides
Discipline of Chemistry, The University of Adelaide, North Terrace, Adelaide, SA 5005, Australia. 2Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, SK S7N 5E2, Canada. Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States. Australian Synchrotron, ANSTO, 800 Blackburn Road, Clayton, VIC 3168, Australia. Centre of Molecular and Macromolecular Studies, Department of Bioorganic Chemistry, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland. Department of Hygienic Chemistry, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-Machi, Nagasaki 852-8521, Japan.
Service type: Stock strains
Abstract
Selenotrisulfides (STS, R-S-Se-S-R) are metabolic intermediates in the bioconversion of inorganic Se species to organoselenium compounds. These Se species are reactive with a variety of endogenous molecules, particularly thiol-containing proteins, with this reactivity facilitating Se transport and subsequent utilization within the body. In this study, X-ray fluorescence microscopy (XFM) and high energy resolution fluorescence detected X-ray absorption spectroscopy (HERFD-XAS) were applied to investigate Se distribution and speciation in vivo. Male rats administered with 1 mg Se/kg b.w. as selenious acid (SA), L-penicillamine selenotrisulfide (PenSSeSPen) or selenenyl penicillamine bound to rat serum albumin (RSA-SSeSPen) showed statistically significant elevations in Se concentrations in the kidney, liver, and blood after 48 h treatment; however, no change in Se concentration was observed in the testes. Notably, XFM revealed a strong colocalization of Se and Cu in the renal cortex, a phenomenon previously observed in cultured cells and in rats fed diets supplemented with 5 mg Se/kg as selenite. Linear combination and principal component analyses of Se Kα1 HERFD-XAS spectra revealed marked differences in Se speciation between the renal cortex and medulla and between red blood cells and plasma for all groups, including the control. STS were identified in linear combination fits of spectra from all tissues, except the testes. These results highlight the vital roles of STS in the intracellular reduction and transport of Se throughout the bloodstream and various tissues.
View Publication