Effects of selected endocrine disruptors on meiotic maturation, cumulus expansion, synthesis of hyaluronan and progesterone by porcine oocyte-cumulus complexes

Toxicol In Vitro. 2009 Apr;23(3):371-7. doi: 10.1016/j.tiv.2008.12.017. Epub 2008 Dec 30.

Abstract

In most mammals, before ovulation, cumulus cells synthesize a large amount of hyaluronan (HA) that is organized into an extracellular matrix (ECM), which provides an essential microenvironment for in vivo oocyte fertilization. This process is called cumulus expansion. The present study assessed effects of selected endocrine disruptors (bisphenol A, BPA; 4-chloro-3-methyl phenol, CMP; di(2-ethylhexyl) phthalate, DEHP; and benzyl butyl phthalate, BBP) in a range of 100pM-100microM, on follicle-stimulating hormone (FSH)-induced meiotic maturation and cumulus expansion of porcine oocyte-cumulus complexes (OCC) cultured in vitro. Moreover, FSH-stimulated production of hyaluronic acid (HA) and progesterone by cumulus cells was measured. Both phenols, BPA and CMP (100microM), significantly affected meiotic maturation of oocytes. The number of oocytes that underwent germinal vesicle breakdown (GVBD) (78.7% and 72.4%, respectively) as well as the rate of oocytes that reached metaphase II stage (MII) (50% and 53.6%, respectively) after 44h culture were decreased compared to control (89.6% for GVBD and 81.5% for MII). FSH-stimulated expansion of cumulus was altered by the highest concentration of BPA and CMP (70% and 64%, respectively vs. 80.3% in control). Although BPA did not alter FSH-stimulated HA synthesis by cumulus cells, its incorporation within the complex was reduced to a half of control value. Progesterone production by OCC was significantly changed in the presence of BPA or DEHP. Finally, our results provide valuable information that oocyte meiotic progression was adversely affected during in vitro culture with endocrine disruptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benzhydryl Compounds
  • Cumulus Cells / drug effects*
  • Cumulus Cells / metabolism
  • Endocrine Disruptors / toxicity*
  • Female
  • Hyaluronic Acid / biosynthesis*
  • Meiosis / drug effects*
  • Meiosis / physiology
  • Mitosis / drug effects
  • Mitosis / physiology
  • Oocytes / drug effects*
  • Oocytes / growth & development
  • Oocytes / metabolism
  • Phenols / toxicity
  • Phthalic Acids / toxicity
  • Progesterone / biosynthesis*
  • Swine

Substances

  • Benzhydryl Compounds
  • Endocrine Disruptors
  • Phenols
  • Phthalic Acids
  • Progesterone
  • Hyaluronic Acid
  • bisphenol A