The testis is a priority organ for developing alternative models to assess male reproductive health hazards of chemicals. This study characterized a 3D in vitro model of murine prepubertal Leydig TM3 cells with improved expression of steroidogenesis markers suitable for image-based screening of testicular toxicity. This 3D scaffold-free spheroid model was applied to explore the impact of prototypical endocrine-disrupting chemicals (EDCs) and environmental reprotoxicants (benzo[a]pyrene, 2- and 9-methylanthracenes, fluoranthene, triclosan, triclocarban, methoxychlor) on male reproductive health. The results were compared to the male reprotoxicity potential of EDCs assessed in a traditional monolayer (2D) culture. The testicular toxicity was dependent not only on the type of culture (2D vs. 3D models) but also on the duration of exposure. Benzo[a]pyrene and triclocarban were the most active compounds, eliciting cytotoxic effects in prepubertal Leydig cells at low micromolar concentrations, which might be a mechanism contributing to their male reprotoxicity.
- MeSH
- benzopyren toxicita MeSH
- endokrinní disruptory * chemie MeSH
- Leydigovy buňky * MeSH
- myši MeSH
- rozmnožování MeSH
- testis MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Aquatic biotests are important tools targeting various effects in ecotoxicology, including endocrine disruption. Unintentional exposure of bioassay organisms to endocrine disruptors during cultivation or testing may interfere with assessed endpoints. We illustrate this issue on the example of laboratory phytoplankton cultivation, where possible sources of estrogenic compounds have been revealed. Fifty-four blank samples (water and fresh or cultivated growth media) were assessed by in vitro biotests for their estrogenicity, and major known estrogens originating from plastic materials, bisphenol A and alkylphenols, were analyzed in selected samples. The samples of freshly prepared growth medium elicited weak estrogenic response in bioassays and some samples of the aerated media caused responses even above the 50% of maximum of the reference compound (17β-estradiol, E2), while the samples from diverse laboratory water sources did not show significant estrogenic activity. The results identified substances contained in the growth medium as minor but reproducible contributors to estrogenicity in the cultivations. Sporadic but significant effects (up to 4.9 ng E2 equivalent/L) can be ascribed to compounds released from the used plastic materials during aeration of the cultivations. The potential sources of unintentional exposure to estrogenic compounds need to be considered in aquatic cultivations and biotests, since they could impact their outcomes, especially in arrangements assessing reproduction or whole life cycle biotests, or production of bioactive compounds by phytoplankton. The findings emphasize the necessity to assess all relevant blanks, ideally by sensitive high throughput in vitro assays that reflect also unknown pollutants and minimize all potential sources of background contamination. In vitro assays show very good applicability for this purpose since they enable to screen for any background estrogenicity of the used media and materials without the need of analyzing individual compounds, which often might not be known.
Phytoplankton can produce various bioactive metabolites, which may affect other organisms in the aquatic environment. This study provides the first information on the total retinoid-like activity associated with both intracellular and extracellular metabolites produced by selected phytoplankton species that could play a role in teratogenic effects and developmental disruption in exposed organisms. The studied species included a coccoid cyanobacteria (Microcystis aeruginosa), a filamentous cyanobacteria (Aphanizomenon gracile) and a green alga (Desmodesmus quadricauda), all of which commonly occur in freshwater bodies in Europe. Methanolic extracts from cellular material and extracellular exudates were prepared from cultures cultivated in two light-intensity variants with five replicates for each species. The retinoid-like activity was evaluated by in vitro assays along with chemical analyses of two potent retinoic acids (all-trans retinoic acid (ATRA) and 9cis-RA). The mean total retinoid-like activity of metabolites produced by the three studied species representing different phytoplankton taxonomic groups ranged from 705 to 5572ng ATRA equivalent/g dry matter corresponding to 0.064-0.234ng ATRA/106 cells. Retinoid-like activity was found in the cellular extracts of all species, while only the extracellular exudates of cyanobacteria exhibited detectable activity (41-1081ng ATRA/L). The greatest extracellular as well as total (extra- and intra- cellular together) retinoid-like activity was detected for Microcystis aeruginosa. The two potent retinoic acids studied were more frequently detected in cellular extracts than in extracellular exudates of all species. Their contribution to observed in vitro effects was relatively low for all tested samples (<10%), indicating a substantial contribution of other retinoid-like compounds to the overall activity. The results indicate possible influence of light intensity and cell density on the production of metabolites with retinoid-like activity and the cyanotoxin microcystin by the studied species. The recalculation of the results per dry weight, water volume, per 106 cells and biovolume enables a direct comparison of the retinoid-like activity distribution between extracts and exudates and the use of the data for risk assessment in water bodies.
- MeSH
- buněčné linie MeSH
- Chlorophyta chemie MeSH
- fytoplankton chemie metabolismus mikrobiologie MeSH
- Microcystis MeSH
- mikrocystiny MeSH
- retinoidy farmakologie MeSH
- rostlinné extrakty farmakologie MeSH
- sinice chemie MeSH
- tretinoin farmakologie MeSH
- viabilita buněk účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH