Here is presented some of the first information on interactions of compounds produced by cyanobacteria and green algae with estrogen receptor signaling. Estrogenic potency of aqueous extracts and exudates (culture spent media with extracellular products) of seven species of cyanobacteria (10 different laboratory strains) and two algal species were assessed by use of in vitro trans-activation assays. Compounds produced by cyanobacteria and algae, and in particular those excreted from the cells, were estrogenic. Most exudates were estrogenic with potencies expressed at 50% of the maximum response under control of the estrogen receptor ranging from 0.2 to 7.2 ng 17β-estradiol (E(2)) equivalents (EEQ)/L. The greatest estrogenic potency was observed for exudates of Microcystis aerigunosa, a common species that forms water blooms. Aqueous extracts of both green algae, but only one species of cyanobacteria (Aphanizomenon gracile) elicited significant estrogenicity with EEQ ranging from 15 to 280 ng 17β-estradiol (E(2))/g dry weight. Scenedesmus quadricauda exudates and extracts of Aphanizomenon flos-aquae were antagonistic to the ER when coexposed to E(2). The EEQ potency was not correlated with concentrations of cyanotoxins, such as microcystin and cylindrospermopsin, which suggests that the EEQ was comprised of other compounds. The study demonstrates some differences between the estrogenic potency of aqueous extracts prepared from the same species, but of different origin, while the effects of exudates were comparable within species. The observed estrogenic potencies are important namely in relation to the possible mass expansion of cyanobacteria and release of the active compounds into surrounding water.

• MeSH
• Aphanizomenon metabolismus   MeSH
• biotest MeSH
• chemické látky znečišťující vodu metabolismus   farmakologie   MeSH
• Chlorophyta metabolismus   MeSH
• endokrinní disruptory metabolismus   farmakologie   MeSH
• estradiol metabolismus   farmakologie   MeSH
• estrogeny metabolismus   farmakologie   MeSH
• eutrofizace MeSH
• exsudáty a transsudáty chemie   MeSH
• mezibuněčná komunikace fyziologie   MeSH
• Microcystis účinky léků   MeSH
• receptory pro estrogeny metabolismus   MeSH
• sinice metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• endokrinní disruptory MeSH
• estradiol MeSH
• estrogeny MeSH
• receptory pro estrogeny MeSH

The biological activity of cyanobacteria and their chemical components have been widely studied due to their blooms in eutrophic waters worldwide. The primary goal of this study was to determine if individual cyanobacterial species and mixtures of cyanobacteria collected from the environment contain compounds with the potential for interaction with signaling pathways of the aryl hydrocarbon receptor (AhR), androgen receptor (AR), estrogen receptor (ER), glucocorticoid receptor (GR) and retinoid acid receptor (RAR). Cytotoxicity and specific toxic potencies of products of freshwater cyanobacteria were determined by use of in vitro reporter gene trans-activation assays. The testing included samples prepared from five selected single cyanobacterial species cultivated in laboratory and five complex cyanobacterial biomasses collected from blooms in surface waters in the Czech Republic. The results demonstrate estrogenic potencies of extracts of cyanobacterial biomasses. Among the laboratory single species, the extract of Planktothrix agardhii (intracellular metabolites) had a potency of estrogenic equivalents (EEQ) of 3.8 ng 17β-estradiol/g dw. The estimates of EEQs of samples prepared from complex cyanobacterial biomasses collected from freshwaters in the Czech Republic ranged from 19 to 2200 ng 17β-estradiol/g dw. Several samples prepared from the environmental cyanobacterial biomasses potentiated the androgenic potency of dihydrotestosterone. There was no dioxin-like, glucocorticoid or anti/retinoic activity observed for any of the extracts studied. Extracts of natural complex cyanobacterial biomasses exhibited greater and more frequent presence of compounds with specific modes of action, mainly estrogenic, and also greater cytotoxicity than extracts of single cyanobacterial species. The demonstrated estrogenic potency of the compounds present in complex cyanobacterial biomasses is of environmental relevance, and could potentially contribute to endocrine disruptive effects in aquatic ecosystems in case of great bloom densities.

• MeSH
• androgenní receptory metabolismus   MeSH
• bakteriální toxiny toxicita   MeSH
• biomasa MeSH
• biotest MeSH
• buněčné linie MeSH
• cytotoxiny toxicita   MeSH
• endokrinní disruptory toxicita   MeSH
• estrogeny toxicita   MeSH
• komplexní směsi toxicita   MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• mikrocystiny toxicita   MeSH
• nádorové buněčné linie MeSH
• receptory aromatických uhlovodíků metabolismus   MeSH
• receptory glukokortikoidů metabolismus   MeSH
• receptory kyseliny retinové metabolismus   MeSH
• receptory pro estrogeny metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• sinice chemie   MeSH
• techniky in vitro MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• androgenní receptory MeSH
• bakteriální toxiny MeSH
• cytotoxiny MeSH
• endokrinní disruptory MeSH
• estrogeny MeSH
• komplexní směsi MeSH
• microcystin MeSH Prohlížeč
• mikrocystiny MeSH
• receptory aromatických uhlovodíků MeSH
• receptory glukokortikoidů MeSH
• receptory kyseliny retinové MeSH
• receptory pro estrogeny MeSH

Attention deficit hyperactivity disorder (ADHD) is a common child diagnosis with frequent comorbidities (Quinn, 2008). According to present studies eating disorders may represent one of them (Mikami et al., 2008). Several studies reported ADHD relation to the higher predisposition to obesity (Altafas, 2002), higher values of signs of overnutrition, as body mass index (Waring and Lapane, 2008) or higher value of fat (Ptacek et al., 2009a, c). These characteristics are considered to be directly related to the disorder. They can be caused by impulsivity and probable specific feeding customs of ADHD patients. The presence of eating disorders in ADHD patients could partially explain previously described growth and weight changes.

• MeSH
• dítě MeSH
• hyperkinetická porucha komplikace   MeSH
• lidé MeSH
• obezita komplikace   MeSH
• poruchy příjmu potravy v dětství komplikace   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH