title: Effects of mono(2-ethylhexyl)phthalate on cytoplasmic maturation of oocytes--The bovine model.
abstract: Phthalates are known reproductive toxicants, but their intracellular disruptive effects on oocyte maturation competence are less known. We studied the potential risk associated with acute exposure of oocytes to mono(2-ethylhexyl)phthalate (MEHP). First, bovine oocytes were matured in vitro with or without 50 μM MEHP and examined for mitochondrial features associated with DNA fragmentation. MEHP increased reactive oxygen species levels and reduced the proportion of highly polarized mitochondria along with alterations in genes associated with mitochondrial oxidative phosphorylation (CYC1, MT-CO1 and ATP5B). In a second set of experiments, we associated the effects of MEHP on meiotic progression with those on cytoplasmic maturation. MEHP impaired reorganization of cytoplasmic organelles in matured oocytes reflected by reductions in category I mitochondria, type III cortical granules and class I endoplasmic reticulum. These alterations are associated with the previously reported reduced developmental competence of MEHP-treated bovine oocytes, and reveal the risk associated with acute exposure.
authors.affiliation: Department of Animal Sciences, Robert H. Smith Faculty of Agriculture, Food and Environment, and Center of Excellence in Agriculture and Environmental Health, the Hebrew University, Rehovot 76100, Israel.
authors.forename: D
authors.initials: D
authors.lastname: Kalo
authors.affiliation: Department of Animal Sciences, Robert H. Smith Faculty of Agriculture, Food and Environment, and Center of Excellence in Agriculture and Environmental Health, the Hebrew University, Rehovot 76100, Israel. Electronic address: roth@agri.huji.ac.il.
authors.forename: Z
authors.initials: Z
authors.lastname: Roth
mesh_terms: D000818:Animals; D002417:Cattle; D002454:Cell Differentiation / Q000187:drug effects; D003593:Cytoplasm / Q000187:drug effects; D053938:DNA Fragmentation; D004051:Diethylhexyl Phthalate / Q000031:analogs & derivatives* / Q000633:toxicity; D005260:Female; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects* / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D004051:Diethylhexyl Phthalate; C016599:mono-(2-ethylhexyl)phthalate
keywords: Bovine; Cytoplasmic maturation; Oocyte; Phthalate