Characterizing the origin of blood plasma proteins from organ tissues in rainbow trout (Oncorhynchus mykiss) using a comparative non-targeted proteomics approach.

Protein expression patterns adapt to various cues to meet the needs of an organism. The dynamicity of an organism's proteome can therefore reveal information about an organism's health. Proteome databases contain limited information regarding organisms outside of medicinal biology. The UniProt human and mouse proteomes are extensively reviewed and ∼50 % of both proteomes include tissue specificity, while >99 % of the rainbow trout proteome lacks tissue specificity. This study aimed to expand knowledge on the rainbow trout proteome with a focus on understanding the origin of blood plasma proteins. Blood, brain, heart, liver, kidney, and gills were collected from adult rainbow trout, plasma and tissue proteins were analyzed using liquid chromatography tandem mass spectrometry. Over 10,000 proteins were identified across all groups. Our data indicated that the majority of the plasma proteome is shared amongst multiple tissue types, though 4-7 % of the plasma proteome is uniquely originated from each tissue (gill > heart > liver > kidney > brain).

Release of reduced inorganic selenium species into waters by the green fresh water algae Chlorella vulgaris.

The common green fresh water algae Chlorella vulgaris was exposed to starting concentrations of 10 µg/L selenium in the form of selenate, selenite, or selenocyanate (SeCN(-)) for nine days in 10% Bold's basal medium. Uptake of selenate was more pronounced than that of selenite, and there was very little uptake of selenocyanate. Upon uptake of selenate, significant quantities of selenite and selenocyanate were produced by the algae and released back into the growth medium; no selenocyanate was released after selenite uptake. Release of the reduced metabolites after selenate exposure appeared to coincide with increasing esterase activity in solution, indicating that cell death (lysis) was the primary emission pathway. This is the first observation of biotic formation of selenocyanate and its release into waters from a nonindustrial source. The potential environmental implications of this laboratory observation are discussed with respect to the fate of selenium in impacted aquatic systems, the ecotoxicology of selenium bioaccumulation, and the interpretation of environmental selenium speciation data generated, using methods incapable of positively identifying reduced inorganic selenium species, such as selenocyanate.

Interaction of stilbene compounds with human and rainbow trout estrogen receptors.

Compounds with stilbene structures are widely used as pharmaceuticals and personal care products (PPCPs) and are present in plants. A suite of stilbene-related compounds, including PPCPs and plant-derived compounds were tested in vitro for interactions with the human and rainbow trout estrogen receptors and in vivo with rainbow trout using vitellogenin levels as a biomarker. Among the compounds with antagonistic activity, the common structural similarity was (in addition to the stilbene backbone) the presence of 4-hydroxy substitution. Stilbene-related compounds found to act as inhibitors at the estrogen receptor included the plant-derived compound resveratrol and two formulations of fluorescent whitening agents used in detergents, 4,4'-bis(2-sulfostyryl)biphenyl and diaminostilbene-1. In the yeast estrogenicity screening assay, the concentrations which caused a 50% inhibition in estrogenic response (IC50s) with the human estrogen receptor ranged from 2.56 x 10(-6) to 2.56 x 10(-6) M. In the rainbow trout estrogen receptor assay, the IC50s ranged from 7.75 x 10(-8) to 1.11 x 10(-5) M. However, in the in vivo rainbow trout vitellogenin assay, tamoxifen was the only stilbene of the compounds tested to have a significant effect as an inhibitor of estrogenicity.