title: Expression of TGFβ superfamily components and other markers of oocyte quality in oocytes selected by brilliant cresyl blue staining: relevance to early embryonic development.
abstract: Brilliant cresyl blue (BCB) is a super-vital stain that has been used to select competent oocytes in different species. One objective of the present study was to assess the relationship between BCB staining, which correlates with an oocyte's developmental potential, and the transcript abundance for select TGFβ-superfamily components, SMAD2/3 and SMAD1/5 phosphorylation levels, and oocyte (JY1) and cumulus-cell (CTSB, CTSK, CTSS, and CTSZ) transcript markers in bovine oocytes and/or adjacent cumulus cells. The capacity of exogenous follistatin or JY1 supplementation or cathepsin inhibitor treatment to enhance development of embryos derived from low-quality oocytes, based on BCB staining, was also determined. Cumulus-oocyte complexes (COCs) from abattoir-derived ovaries were subjected to BCB staining, and germinal-vesicle-stage oocytes and cumulus cells were harvested from control, BCB+, and BCB- (low-quality oocyte) groups for real-time PCR or Western-blot analysis. Remaining COCs underwent in vitro maturation, in vitro fertilization, and embryo culture in the presence or absence of the above exogenous supplements. Levels of FST, JY1, BMP15, and SMAD1, 2, 3, and 5 transcripts were higher in BCB+ oocytes whereas CTSB, CTSK, CTSS, and CTSZ mRNA abundance was higher in cumulus cells surrounding BCB- oocytes. Western-blot analysis revealed higher SMAD1/5 and SMAD2/3 phosphorylation in BCB+ than BCB- oocytes. Embryo-culture studies demonstrated that follistatin and cathepsin inhibitor treatment, but not JY-1 treatment, improve the developmental competence of BCB- oocytes. These results contribute to a better understanding of molecular indices of oocyte competence.
authors.affiliation: Laboratory of Mammalian Reproductive Biology and Genomics, Department of Animal Science, Michigan State University, East Lansing, Michigan; Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Ashry
authors.forename: KyungBon
authors.initials: K
authors.lastname: Lee
authors.forename: Mohan
authors.initials: M
authors.lastname: Mondal
authors.forename: Tirtha K
authors.initials: TK
authors.lastname: Datta
authors.forename: Joseph K
authors.initials: JK
authors.lastname: Folger
authors.forename: Sandeep K
authors.initials: SK
authors.lastname: Rajput
authors.forename: Kun
authors.initials: K
authors.lastname: Zhang
authors.forename: Nabil A
authors.initials: NA
authors.lastname: Hemeida
authors.forename: George W
authors.initials: GW
authors.lastname: Smith
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D015153:Blotting, Western; D002417:Cattle; D054885:Cumulus Cells / Q000378:metabolism / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D046149:Embryo Culture Techniques; D047108:Embryonic Development / Q000502:physiology*; D005307:Fertilization in Vitro; D038681:Follistatin / Q000494:pharmacology; D020869:Gene Expression Profiling; D059471:In Vitro Oocyte Maturation Techniques; D009865:Oocytes / Q000378:metabolism / Q000502:physiology*; D010078:Oxazines; D010766:Phosphorylation; D060888:Real-Time Polymerase Chain Reaction; D051785:Smad Proteins / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D017931:DNA Primers; D038681:Follistatin; D010078:Oxazines; D051785:Smad Proteins; D016212:Transforming Growth Factor beta; C006797:Brilliant Cresyl Blue