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Publications (152) View all
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Article: Expression levels of mRNA for insulin-like growth factors 1 and 2, IGF receptors and IGF binding proteins in in vivo and in vitro grown bovine follicles.
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ABSTRACT: Summary This study investigated mRNA levels for insulin-like growth factors (IGFs) IGF1 (IGF-I) and IGF2 (IGF-II), IGF receptors (IGF1R and IGF2R), and binding proteins (IGFBP-1, IGFBP-2. IGFBP-3, IGFBP-4, IGFBP-5 and IGFBP-6) in bovine follicles of 0.2, 0.5 or 1.0 mm in diameter. mRNA expression levels in in vitro cultured follicles that reached approximately 0.5 mm were compared with that of in vivo grown follicles. IGF1R and IGF2R expression levels in 0.5 mm in vivo follicles were higher than in 1.0 or 0.2 mm follicles, respectively. IGFBP-1, IGFBP-2. IGFBP-3, IGFBP-4, IGFBP-5 and IGFBP-6 showed variable expression in the follicular size classes analyzed. In vitro grown follicles had significantly reduced expression levels for IGF1, IGF1R, IGFBP-3, IGFBP-5 and IGFBP-6 mRNA when compared with 0.2 mm follicles, but, when compared with in vivo grown follicles (0.5 mm), only IGFBP-1, IGFBP-2, IGFBP-3 and IGFBP-6 showed a reduction in their expression. In conclusion, IGFs, their receptors and IGFBPs showed variable expression of mRNA levels in the follicular size classes analyzed.Zygote 05/2013; · 1.17 Impact Factor -
Article: Expression of bone morphogenetic protein2 (BMP2), BMP4 and BMP receptors in the bovine ovary but absence of effects of BMP2 and BMP4 during IVM on bovine oocyte nuclear maturation and subsequent embryo development.
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ABSTRACT: Bone morphogenetic proteins (BMPs) have been implicated in the regulation of ovarian follicular development and are promising candidates to apply in IVM and IVF protocols. We investigated the expression of BMP2, BMP4 and BMP receptors in bovine ovaries and the effects of BMP2 and BMP4 during oocyte maturation on bovine IVM. Reverse transcription polymerase chain reaction studies with antral follicles showed the expression of BMPR-IA, BMPR-IB, ActR-IA, ActR-IIB, BMPR-II and BMP4 mRNA in all follicular compartments, while BMP2 mRNA was generally restricted to theca and cumulus tissue. Immunohistochemistry demonstrated the presence of BMPR-II in oocytes and granulosa cells of preantral follicles but only in oocytes of antral follicles. The immunostaining of BMP2 and BMP4 was limited to theca interna and approximately 25% of oocytes of antral follicles. Exogenously added BMP2 or BMP4 to IVM medium did not affect oocyte nuclear maturation, cumulus cell expansion, nor blastocyst formation following IVF. It is concluded that a BMP-signaling system, consisting of BMP2, BMP4, type II and I receptors, is present in bovine antral follicles and that this system plays a role in development and functioning of these follicles rather than in final oocyte maturation and cumulus expansion.Theriogenology 03/2005; 63(3):872-89. · 1.96 Impact Factor -
Article: Expression of mRNA and protein localization of epidermal growth factor and its receptor in goat ovaries.
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ABSTRACT: To examine the possibility that epidermal growth factor (EGF) and its receptor (EGF-R) are expressed throughout folliculogenesis, we studied the presence and distribution of EGF and EGF-R in goat ovaries. Ovaries of goats were collected and either fixed in paraformaldehyde for immunohistochemical localization of proteins, or used for the isolation of follicles, luteal cells and ovarian surface epithelium to study mRNA expression for EGF and EGF-R, using the reverse transcriptase polymerase chain reaction. EGF protein and mRNA were found in primordial, primary and secondary follicles as well as in small and large antral follicles and in surface epithelium, but in corpora lutea only the protein could be detected. Antral follicles expressed EGF mRNA in oocyte, cumulus, mural granulosa and theca cells. For EGF-R, both protein and mRNA were present at all stages of follicular development and in all antral follicular compartments. EGF-R protein and mRNA were also found in corpora lutea and surface epithelium. It is concluded that EGF and its receptor are expressed in goat ovarian follicles at all stages of follicle development, in corpora lutea, and in ovarian surface epithelium.Zygote 06/2006; 14(2):107-17. · 1.17 Impact Factor -
Article: Formation of mammalian oocytes and their growth, differentiation and maturation within ovarian follicles.
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ABSTRACT: The limited knowledge on the regulation of oocyte formation, the different steps of folliculogenesis and the required conditions for oocytes to undergo proper growth, differentiation and maturation are major causes of the failure in obtaining viable offspring from in vitro cultured early oocytes from domestic animals and humans. This review highlights the factors that at present are known to be involved in the formation of mammalian oocytes and their growth, differentiation and maturation within ovarian follicles.Theriogenology 05/2005; 63(6):1717-51. · 1.96 Impact Factor -
Article: Immunocytochemical detection and reverse transcription polymerase chain reaction expression of oncostatin M (OSM) and its receptor (OSM-Rbeta) in human fetal and adult ovaries.
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ABSTRACT: To investigate the immunocytochemical expression and presence of mRNA transcripts of oncostatin M (OSM) and its exclusive receptor (OSM-Rbeta) in ovaries from human adults and fetuses. Immunocytochemical and reverse transcription polymerase chain reaction (RT-PCR) study. Major tertiary care and referral academic centers. Ten women and girls undergoing laparoscopic ovarian biopsy and 30 women undergoing second-trimester and third-trimester pregnancy terminations. None. Microscopic morphometric analysis, immunocytochemistry for OSM and OSM-Rbeta, and RT-PCR analyses. There was strong to moderate immunocytochemical staining for OSM in both oocytes and granulosa cells of follicles from primordial stages onwards in ovaries from both fetuses and adults/adolescents. OSM-Rbeta was detected mainly in the oocytes. Transcripts of OSM and OSM-Rbeta RNA were detected by RT-PCR analyses. The expression of OSM and its receptor in ovarian tissue from fetuses and women suggests a possible role of OSM in growth initiation of human primordial follicles.Fertility and Sterility 05/2005; 83 Suppl 1:1188-96. · 3.56 Impact Factor
