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Cellular and molecular mechanisms mediating the effect of polychlorinated biphenyls on oocyte in vitro maturation

Department of Anatomy of Domestic Animals, University of Milano, 20133 Milano, Italy.
Reproductive Toxicology (Impact Factor: 2.77). 09/2006; 22(2):242-9. DOI: 10.1016/j.reprotox.2006.04.023
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ABSTRACT Cellular and molecular mechanisms mediating the effect of polychlorinated biphenyls on oocyte in vitro maturation: Polychlorinated biphenyls (PCBs) are stable, lipophilic compounds that accumulate in the environment and in the food chain. Recent studies provide evidence that exposure to PCBs can cause reproductive problems. PCBs have been identified in the ovarian follicle of women and other mammals and many data in the literature clearly indicate that both follicles and oocytes are particularly susceptible to these pollutants. In the present review we describe the multifaceted effects of PCBs on mammalian oocyte maturation in detail. Published studies clearly indicate that PCB congeners, both singly or as complex mixtures, disrupt mammalian oocyte maturation and subsequent embryo development. Specifically, data point out to the ability of PCBs to interfere with the organization of the microtubules cytoplasmic network resulting in an altered compartmentalization of the ooplasm. Furthermore, a critical role of cumulus cells in mediating PCB ovotoxicity has been observed, most likely related to a disregulation in intracellular communication between the germinal and the somatic compartment. Finally, since coplanar PCBs, induce gene expression via a ligand-dependent transactivating factor, the aryl hydrocarbon receptor, this signalling pathway is also reviewed with respect to understanding the toxic mechanisms of these compounds.

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    • "Due to their stability and lipophilic character, PCBs persist in the environment and accumulate in fatty tissues of animals and humans (Kimbrough, 1995; Hansen, 1999). PCBs are well known as potential neurotoxic (Seegal et al., 2005), teratogenic, and embriotoxic agents, effecting the embryonic development in fish (Arzuaga et al., 2004), birds (Hoffman et al., 1996; Summer et al., 1996), rodents (Goodwill et al., 2007; Kimura-Kuroda et al., 2007) and humans (Pocar et al., 2006; Roegge and Schantz 2006). PCBs can also contribute to the development of cancer in experimental animals (Carpenter, 2006; Knerr and Schrenk, 2006; Lehmann et al., 2007) and are classified as the probable carcinogens in humans (class 2A carcinogens according to the IARC classification) (Shields, 2006). "
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