Estrogenic and anti-estrogenic influences in cultured brown trout hepatocytes: Focus on the expression of some estrogen and peroxisomal related genes and linked phenotypic anchors

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Madureira, TV (Author) Other; Malhao, F (Author) Other; Pinheiro, I (Author) Other; Lopes, C (Author) Other; Ferreira, N (Author) Other; Urbatzka, R (Author) Other; Filipe F C Castro (Author) FCUP; rocha, e (Author) ICBAS

Journal

Title: Aquatic Toxicology

Vol. 169

Pages: 133-142

ISSN: 0166-445X

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 13 Citations

Scopus - 14 Citations

Other information

Authenticus ID: P-00G-VJR

DOI: 10.1016/j.aquatox.2015.10.010

Abstract (EN): Estrogens, estrogenic mimics and anti-estrogenic compounds are known to target estrogen receptors (ER) that can modulate other nuclear receptor signaling pathways, such as those controlled by the peroxisome proliferator-activated receptor (PPAR), and alter organelle (inc. peroxisome) morphodynamics. By using primary isolated brown trout (Salmo trutta f. fario) hepatocytes after 72 and 96 h of exposure we evaluated some effects in selected molecular targets and in peroxisomal morphological features caused by: (1) an ER agonist (ethinylestradiol-EE2) at 1,10 and 50 mu M; (2) an ER antagonist (ICI 182,780) at 10 and 50 mu M; and (3) mixtures of both (Mix 1-10 mu M EE2 and 50 mu M ICI; Mix II-1 mu M EE2 and 10 mu M ICI and Mix III-1 mu M EE2 and 50 mu M ICI). The mRNA levels of the estrogenic targets (ER alpha, ER beta-1 and vitellogenin A-VtgA) and the peroxisome structure/function related genes (catalase, urate oxidase-Uox, 17 beta-hydroxysteroid dehydrogenase 4-17 beta-HSD4, peroxin 11 alpha-Pex11a and PPAR alpha) were analyzed by real-time polymerase chain reaction (RT-PCR). Stereology combined with catalase immunofluorescence revealed a significant reduction in peroxisome volume densities at 50 mu M of EE2 exposure. Concomitantly, at the same concentration, electron microscopy showed smaller peroxisome profiles, exacerbated proliferation of rough endoplasmic reticulum, and a generalized cytoplasmic vacuolization of hepatocytes. Catalase and Uox mRNA levels decreased in all estrogenic stimuli conditions. VtgA and ER alpha mRNA increased after all EE2 treatments, while ER beta-1 had an inverse pattern. The EE2 action was reversed by ICI 182,780 in a concentration-dependent manner, for VtgA, ER alpha and Uox. Overall, our data show the great value of primary brown trout hepatocytes to study the effects of estrogenic/anti-estrogenic inputs in peroxisome kinetics and in ER and PPAR alpha signaling, backing the still open hypothesis of crosstalk interactions between these pathways and calling for more mechanistic experiments.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10