Snooping on a private conversation between the oviduct and gametes/embryos

Article suite au congrès :31st Meeting of the European-Embryo-Transfer-Association (AETE). 11-12 September 2015, Ghent, BelgiqueAfter a long journey travelling up the maternal tract the spermatozoa will meet the oocyte. As a result, an early embryo will promptly commence its development while travelling down the oviduct. These short but vital journeys of gametes and embryos are accompanied by important changes in the maternal tract. In particular, from the oviduct, which provides an optimal environment for gamete maturation and transport, fertilization and early embryo development. In fact, to achieve a successful pregnancy the oviduct should keep a fruitful dialogue with the gametes followed by an appropriate communication with the embryo(s). In the present review, the transcriptomic and proteomic changes induced by gametes and embryos in the oviduct as a result of this early dialogue will be reported. A special mention of the differential conversation between the oviduct and X and Y-chromosome-bearing spermatozoa, which might be at the basis of gender selection, will be provided. Subsequently, the ability of the embryo to modulate its own oviductal environment thus avoiding its maternal rejection will be discussed. Ultimately, a third player will be introduced in this dialogue, exosomes/microvesicles, which have been proposed as early mediators of these maternal-gamete/embryo interactions. Snooping on the private conversation between the oviduct and gametes/embryo may provide some molecular clues about the mechanisms that mediate these interactions. Moreover, knowing the genes and proteins that pilot the success of the early reproductive events will offer great opportunities for the improvement of assisted reproductive technologies and animal breeding efficiency

What is new in the cryopreservation of embryos?

International audienceEmbryo cryopreservation represents a pivotal tool for the long-term storage and exchange of valuable genetic resources of livestock and endangered species. The innumerable applications of embryo cryopreservation in human medicine, animal production, as well as in other embryo biotechnologies for research purposes are calling for standardized protocols that can be used in these different fields. This review will provide the reader with a brief outline to "the classics" of embryo cryopreservation procedures in farm animals and with a deeper insight into "the new trends". Moreover, the cryopreservation effects on the embryo will be revised; from the easily visible cellular damage to the damage at the transcriptomic, proteomic and lipidomic level, and fresh attention will be given to the epigenetic effects of this technology. Finally, we will go through personal considerations to take into account when embryo cryopreservation is used: how to select the best embryos for cryopreservation, the eternal question for how long can we store the cryopreserved embryos, the fact that size and fat matter when it comes to embryo cryopreservation and ultimately, our suggestion about designing cryopreservation protocols "a la carte" attending the needs of each type of embryo

Extracellular vesicles: Multi-signal messengers in the gametes/embryo-oviduct cross-talk

Extracellular vesicles (EVs) have emerged as novel cell-to-cell communication mediators in physiological and pathological scenarios. Their ability to transfer their molecular cargo (RNAs, proteins and lipids) from one cell to another, in the vicinity or far from the cell of origin, together with their capacity of exerting a functional impact on the target cell make them valuable diagnostic tools as well as therapeutic vectors in a variety of diseases. In the reproductive field, there is a growing interest in the role of EVs in gamete/embryo-maternal communication and their potential implications in the reproductive success. In this review, we provide current knowledge of EVs secreted by the oviduct (oEVs) and embryos (eEVs), since both have been proposed as key players in the crucial two-way dialogue between the oviduct (lining epithelium and secretions) and the embryo that ensures successful pregnancy. Both oEVs and eEVs molecular cargos and their potential role as multi-signal messengers in the gametes/embryo-oviduct cross-talk and in the embryo-to-embryo communication in different species are also addressed. Eventually, a comparative analysis between oEVs and eEVs has been performed to shed some light on common and specific cargos responsible for their functions supporting the early reproductive events and as prime candidate molecules for improving fertility and assisted reproductive technologies outcomes

Oviductal exosome supplementation improves bovine in vitro blastocyst yield and quality

National audienc

Pentoxifylline added to post-thaw extender does not improve the survival and the efficiency in vitro of boar spermatozoa

Pentoxifylline added to post-thaw extender does not improve the survival and the efficiency in vitro of boar spermatozo

Characterization of bovine oviductal exosomes from in vivo and in vitro origin

National audienc

Seminal Plasma Proteins as Modulators of the Sperm Function and Their Application in Sperm Biotechnologies

International audienceContents Somatic cell nuclear transfer (SCNT) was first developed in livestock for the purpose of accelerating the widespread use of superior genotypes. Although many problems still exist now after fifteen years of research owing to the limited understanding of genome reprogramming, SCNT has provided a powerful tool to make copies of selected individuals in different species, to study genome pluripotency and differentiation, opening new avenues of research in regenerative medicine and representing the main route for making transgenic livestock. Besides well-established methods to deliver transgenes, recent development in enzymatic engineering to edit the genome provides more precise and reproducible tools to target-specific genomic loci especially for producing knockout animals. The interest in generating transgenic livestock lies in the agricultural and biomedical areas and it is, in most cases, at the stage of research and development, with few exceptions that are making the way into practical applications

Deciphering the oviductal extracellular vesicles content across the estrous cycle: implications for the gametes-oviduct interactions and the environment of the potential embryo

International audienceBackground: The success of early reproductive events depends on an appropriate communication between gametes/embryos and the oviduct. Extracellular vesicles (EVs) contained in oviductal secretions have been suggested as new players in mediating this crucial cross-talk by transferring their cargo (proteins, mRNA and small ncRNA) from cell to cell. However, little is known about the oviductal EVs (oEVS) composition and their implications in the reproductive success. The aim of the study was to determine the oEVs content at protein, mRNA and small RNA level and to examine whether the oEVs content is under the hormonal influence of the estrous cycle. Results: We identified the presence of oEVs, exosomes and microvesicles, in the bovine oviductal fluid at different stages of the estrous cycle (postovulatory-stage, early luteal phase, late luteal phase and pre-ovulatory stage) and demonstrated that their composition is under hormonal regulation. RNA-sequencing identified 903 differentially expressed transcripts (FDR 2). Our data revealed proteins related to early embryo development and gamete-oviduct interactions as well as numerous ribosomal proteins. Conclusions: Our study provides with the first molecular signature of oEVs across the bovine estrous cycle, revealing marked differences between post- and pre-ovulatory stages. Our findings contribute to a better understanding of the potential role of oEVs as modulators of gamete/embryo-maternal interactions and their implications for the reproductive success

Interception of exosomal messages between the oviduct and the embryo: What are they tweeting about?

International audienc