Primate model of metaphase I oocyte in vitro maturation and the effects of a novel glutathione donor on maturation, fertilization, and blastocyst development

Received 27 December 2009; received in revised form 13 May 2010; accepted 15 June 2010. published online 29 July 2010.
Corrected Proof

Objective

To assess the effect of glutathione ethyl ester (GSH-OEt) on the development of macaque metaphase (MI) oocytes as a model for human MI oocyte in vitro maturation (IVM).

Design

Prospective cohort study.

Setting

Nonhuman primate assisted reproductive technology program.

Animal(s)

Twenty-three Macaca fascicularis females aged 6.5–12.5 years.

Intervention(s)

Ovarian stimulation and maturation of MI oocytes in [1] human tubal fluid (HTF), [2] mCMRL-1066, [3] mCMRL-1066+GSH-OEt 3 mM, or [4] mCMRL-1066+GSH-OEt 5 mM. Oocytes were assessed for maturation after 4–6 hours (early) and 18–20 hours (late) of culture. Mature oocytes were inseminated or subjected to glutathione (GSH) assay. Zygotes were cultured to the blastocyst stage for total differential cell counts.

Main Outcome Measure(s)

Oocyte maturation rate, GSH content, pronuclear formation and blastocyst development, and cell number were compared between IVM treatment groups and sibling in vivo matured (IVO) MII oocytes.

Result(s)

Compared with HTF, mCMRL-1066 supported higher rates of normal fertilization and blastocyst development in early but not late maturing MI-MII oocytes. Five micromoles of GSH-OEt significantly increased blastocyst total cell and inner cell mass cell number in early MI-MII oocytes compared with IVO and IVM controls. GSH-OEt significantly increased oocyte GSH content and fertilization in late maturing oocytes but not blastocyst development.

Conclusion(s)

GSH-OEt positively affects the development of early and late maturing IVM oocytes.

Key Words: Glutathione ethyl ester, nonhuman primate, oocyte in vitro maturation, male pronucleus formation

a Washington National Primate Research Center, University of Washington, Seattle, Washington, USA

b Sydney Medical School, University of Sydney, New South Wales, Australia

c IVF Australia, Greenwich, New South Wales, Australia

Reprint requests: Eliza C. Curnow, M.Sc., Washington National Primate Research Center, University of Washington, P.O. Box 357330, Seattle, Washington, 98121 (FAX: 1-206-543-1589).

E.C.C. has nothing to disclose. J.P.R. has nothing to disclose. D.M.S. has nothing to disclose. E.S.H. has nothing to disclose.

This work was supported by the National Center for Research Resources, Seattle, Washington (P51 grant no. RR00166).

PII: S0015-0282(10)00982-9

doi:10.1016/j.fertnstert.2010.06.029