title: Immunomodulation of Mytilus hemocytes by individual estrogenic chemicals and environmentally relevant mixtures of estrogens: in vitro and in vivo studies.
abstract: Endocrine disrupting compounds (EDCs) are almost ubiquitous in the aquatic environment. In the marine bivalve Mytilus the natural estrogen 17beta-estradiol (E2) and different EDCs have been recently demonstrated to affect the function of the immune cells, the hemocytes. The effects were Tamoxifen-sensitive and were mediated by rapid modulation of kinase-mediated transduction pathways. In this work we compared the in vitro effects of individual estrogenic chemicals (E2, EE: 17alpha-ethynyl estradiol; MES: mestranol; NP: nonylphenol; NP1EC: nonylphenol monoethoxylate carboxylate; BPA: bisphenol A; BP: benzophenone) on hemocyte parameters: lysosomal membrane stability (LMS), phagocytosis, lysozyme release. LMS was the most sensitive effect parameter, showing a decreasing trend at increasing concentrations of estrogens. EC50 values obtained from LMS data were utilized to calculate the estradiol equivalency factor (EEF) for each compound; these EEFs allowed for an estimation of the estrogenic potential of a synthetic mixture with a composition very similar to that previously found in waters of the Venice lagoon. Concentrated mixtures significantly affected hemocyte parameters in vitro and the effects were prevented by Tamoxifen. Significant effects of the mixture were also observed in vivo, at longer exposure times and at concentrations comparable with environmental exposure levels. The results indicate that Mytilus immune parameters can be suitably utilized to evaluate the estrogenic potential of environmental samples.
authors.affiliation: Dipartimento di Biologia, Università di Genova, Corso Europa 26, Genova 16132, Italy. Laura.Canesi@unige.it
authors.forename: Laura
authors.initials: L
authors.lastname: Canesi
authors.forename: Lucia Cecilia
authors.initials: LC
authors.lastname: Lorusso
authors.forename: Caterina
authors.initials: C
authors.lastname: Ciacci
authors.forename: Michele
authors.initials: M
authors.lastname: Betti
authors.forename: Marco
authors.initials: M
authors.lastname: Rocchi
authors.forename: Giulio
authors.initials: G
authors.lastname: Pojana
authors.forename: Antonio
authors.initials: A
authors.lastname: Marcomini
mesh_terms: D000818:Animals; D052244:Endocrine Disruptors / Q000633:toxicity*; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods; D004958:Estradiol / Q000633:toxicity; D004967:Estrogens / Q000633:toxicity*; D004997:Ethinyl Estradiol / Q000633:toxicity; D006434:Hemocytes / Q000187:drug effects* / Q000276:immunology; D008247:Lysosomes / Q000187:drug effects; D008656:Mestranol / Q000633:toxicity; D049878:Mytilus / Q000187:drug effects* / Q000276:immunology; D010587:Phagocytosis / Q000187:drug effects; D013629:Tamoxifen / Q000494:pharmacology; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D052244:Endocrine Disruptors; D004967:Estrogens; D014874:Water Pollutants, Chemical; D013629:Tamoxifen; D004997:Ethinyl Estradiol; D004958:Estradiol; D008656:Mestranol