Effects of different oocyte retrieval and in vitro maturation systems on bovine embryo development and quality. Issue 3 (June 2015)

• Record Type: Journal Article
• Authors: Bernal, Sandra Milena; Heinzmann, Julia; Herrmann, Doris; Timmermann, Bernd; Baulain, Ulrich; Großfeld, Rudolf; Diederich, Mike; Lucas-Hahn, Andrea; Niemann, Heiner
• Is Part Of: Zygote. Volume 23:Issue 3(2015)
• Page Start: 367
• Page End: 377
• Publication Date: 2015-06
• Subjects: Developmental biology -- Periodicals; Embryology -- Periodicals; Zygotes -- Periodicals; Gametes -- Periodicals; 571.864
• DOI: 10.1017/S0967199413000658
• Languages: English
• ISSNs: 0967-1994

Abstract

<abstract abstract-type="normal"> <title>Summary</title> <p>Cyclic adenosine monophosphate (cAMP) modulators have been used to avoid spontaneous oocyte maturation and concomitantly improve oocyte developmental competence. The current work evaluated the effects of the addition of cAMP modulators forskolin, 3-isobutyl-1-methylxanthine (IBMX) and cilostamide during <italic>in vitro</italic> maturation on the quality and yields of blastocysts. The following experimental groups were evaluated: (i) slicing or (ii) aspiration and maturation in tissue culture medium (TCM)199 for 24 h (TCM24slicing and TCM24aspiration, respectively), (iii) aspiration and maturation in the presence of cAMP modulators for 30 h (cAMP30aspiration) and <italic>in vivo</italic>-produced blastocysts. <italic>In vitro</italic>-matured oocytes were fertilized and presumptive zygotes were cultured <italic>in vitro</italic> to assess embryo development. Cleavage, blastocyst formation, blastocyst cell number, mRNA abundance of selected genes and global methylation profiles were evaluated. Blastocyst rate/zygotes for the TCM24aspiration protocol was improved (32.2 ± 2.1%) compared with TCM24slicing and cAMP30aspiration (23.4 ± 1.2% and 23.3 ± 2.0%, respectively, <italic>P<</italic>0.05). No statistical differences were found for blastocyst cell numbers. The mRNA expression for the <italic>EGR1</italic> gene was down-regulated eight-fold in blastocysts that had been produced <italic>in vitro</italic> compared with their <italic>in vivo</italic> counterparts. Gene expression profiles for <italic>IGF2R</italic>, <italic>SLC2A8</italic>, <italic>COX2</italic>, <italic>DNMT3B</italic> and <italic>PCK2</italic> did not differ among experimental groups. Bovine testis satellite I and <italic>Bos taurus</italic> alpha satellite methylation profiles from cAMP30aspiration protocol-derived blastocysts were similar to patterns that were observed in their <italic>in vivo</italic> equivalents (<italic>P</italic> > 0.05), while those from the other groups were significantly elevated. It is concluded that retrieval, collection systems and addition of cAMP modulators can affect oocyte developmental competence, which is reflected not only in blastocyst rates but also in global DNA methylation and gene expression patterns.</p> </abstract>