Alteration of steroidogenesis in H295R cells by organic sediment contaminants and relationships to other endocrine disrupting effects.
A novel bioassay with the human adrenocortical carcinoma cell line H295R can be used to screen for endocrine disrupting chemicals that affect the expression of genes important in steroidogenesis. This assay was employed to study the effects of organic contaminants associated with the freshwater pond sediments collected in the Ostrava-Karvina region, Czech Republic. The modulation of ten major genes involved in the synthesis of steroid hormones (CYP11A, CYP11B2, CYP17, CYP19, 17betaHSD1, 17betaHSD4, CYP21, 3betaHSD2, HMGR, StAR) after exposure of H295R cells to sediment extracts was investigated using quantitative real-time polymerase chain reaction (PCR). Crude sediment extracts, containing high concentrations of polycyclic aromatic hydrocarbons (PAHs) and moderate amounts of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) significantly stimulated expression of the CYP11B2 gene (up to 10-fold induction), and suppressed expression of 3betaHSD2 and CYP21 genes. A similar pattern was observed with the extracts after treatment with concentrated sulfuric acid to remove labile chemicals (including PAHs) leaving only persistent PCBs, OCPs and potentially PCDD/Fs. Comparison of the results with other mechanistically based bioassays (arylhydrocarbon receptor, AhR, mediated responses in H4IIE-luc cells, and estrogen receptor mediated effects in MVLN cells) revealed significant endocrine disrupting potencies of organic contaminants present in the sediments (most likely antiestrogenicity). Pronounced effects were observed particularly in sediment extracts from the Pilnok Pond which harbors an unusual intersexual population of the narrow-cawed crayfish Pontastacus leptodactylus (Decapoda, Crustacea). This pilot study provided the first experimental evidence of the wider application of the H295R bioassay for screening complex environmental samples, and the results support the hypothesis of chemical-induced endocrine disruption in intersexual crayfish.
Bláha
Ludek
L
RECETOX--Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University, Kamenice 3, CZ62500 Brno, Czech Republic. blaha@recetox.muni.cz
Hilscherová
Klára
K
Mazurová
Edita
E
Hecker
Markus
M
Jones
Paul D
PD
Newsted
John L
JL
Bradley
Patrick W
PW
Gracia
Tannia
T
Duris
Zdenek
Z
Horká
Ivona
I
Holoubek
Ivan
I
Giesy
John P
JP
D045744:Cell Line, Tumor; D052244:Endocrine Disruptors / Q000032:analysis / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects*; D019015:Geologic Sediments / Q000737:chemistry; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000032:analysis / Q000633:toxicity; D007306:Insecticides; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics* / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000633:toxicity; D018336:Receptors, Aryl Hydrocarbon / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D000098682:Steroidogenic Acute Regulatory Protein
D052244:Endocrine Disruptors; D006843:Hydrocarbons, Chlorinated; D007306:Insecticides; D010750:Phosphoproteins; D011084:Polycyclic Aromatic Hydrocarbons; D018336:Receptors, Aryl Hydrocarbon; D011960:Receptors, Estrogen; D014874:Water Pollutants, Chemical; D000098682:Steroidogenic Acute Regulatory Protein; D010088:Oxidoreductases