Reproduction Abstracts

Introduction: A high concentration of polyvinylpyrrolidone (PVP, average molecular weight 360 000) supplementation in culture medium exerts a positive influence on the growth and morphological organization of bovine oocyte–cumulus/granulosa cell complexes in a long-term culture. The objective of the present study was to determine the effect of PVP supplementation on the number of transzonal projections (TZPs) traversing the zona pellucida from cumulus cells to the oocyte....

Pigs provide outstanding models of human genetic diseases due to the striking similarities to human anatomy, physiology and genetics. Pig induced pluripotent stem cells (piPSCs) have been generated for several years but the cloning efficiency using unsynchronized piPSCs was extremely low. Here, we reported a method to produce diploid cloned embryos from piPSCs which were synchronized to metaphase. The piPSCs cell line was established using a drug-inducible system and exhibit s...

Female meiosis involves a highly asymmetrical division to form a large secondary oocyte and a small polar body. Polo-like kinase I (Plk1) is a serine/threonine kinase which is highly conserved from yeast to human and is a potent regulator of mitosis including cytokinesis. Plk1 is known to regulate myosin via the activation of RhoA which leads to the contraction of the cleavage furrow in mitotic cells. Indirect evidence has also shown that Plk1 may regulate Cdc42 activity throu...

Cyclin A, the first cyclin ever cloned, is thought to be an essential component of the cell-cycle engine. Mammalian cells encode two A-type cyclins, a testis-specific cyclin A1 and a ubiquitously expressed cyclin A2. Cyclin A2 is an essential mitotic CDK regulatory partner and is attributed with a wide range of effects early in the G2–M transition. Although its role in mitosis has been extensively investigated, research into the role of cyclin A2 in meiosis is lacking. In...

The role of cumulus cells during in vitro maturation is essential for proper oocyte maturation and acquisition of its developmental competence. During development of ovarian follicle, cumulus cells undergo expansion, leading to extracellular matrix production (mainly hyaluronic acid), regulated by various intracellular signaling cascades. Moreover, cumulus cells metabolize glucose to pyruvate or lactate, substrates used by oocyte for its growth and maturation. We demo...

Introduction: Multi-subunit protein complexes, called condensin I and condensin II, play a pivotal role in construction and segregation of mitotic chromosomes in many organisms. In mammals, however, previous studies examining condensins’ function are limited to siRNA-mediated knockdown experiments using some established cell lines. Hence the roles of both condensins in mammalian development have remained to be solved. In the present study, we have investigated defective p...

The hollow fiber vitrificaiton (HFV) method, we developed (Matsunari et al., JRD 58, 2012) has been shown to be very effective in the cryopreservation of highly cryosensitive embryos, such as in vitro matured-fertilized pig morulae. The objective of this study was to verify the effectiveness of the HFV method to the in vitro matured-fertilized bovine embryos in early developmental stage. Crossbred (Holstein×Japanese Black) in vitro matured-ferti...

This study was designed to investigate whether acteoside (antioxidant) improves canine SCNT efficiency. Cell cycle of canine fetal fibroblasts was synchronized by culturing to contact inhibition, serum starvation and treating with acteoside. Cell cycle synchronization, apoptosis and reactive oxygen species (ROS) detection were analyzed using flow cytometry. The fibroblasts, prepared by confluent-cell culture or treating with 30 μM acteoside for 48 h, were reconstructed in...

Introduction: Human germ cells develop in synchronised nests in the fetal ovary, interspersed with somatic cells prior to reorganisation to form primordial follicles. We have isolated several somatic cell lines from disaggregated human fetal ovaries as a model for understanding their contribution to the germ cell niche. Fetal dysregulation of TGFβ signalling has been linked with fibrosis in polycystic ovary syndrome (PCOS): effects of TGFβ on extracellular matrix (EC...

Introduction: The present study aims to investigate the effect of resveratrol supplementation on the in vitro development of porcine oocytes derived from early antral follicles.Materials and methods: Oocyte-granulosa cell complexes (OGCs) were collected from early antral follicles that were 0.5–0.7 mm in diameter and cultured in the absence or present of resveratrol (2 μM) for 14 days. The effect of resveratrol on SIRT1 expression was ...