Hyaluronic acid and epidermal growth factor improved the bovine embryo quality by regulating the DNA methylation and expression patterns of the focal adhesion pathway

Autoři: Mohammed Saeed-Zidane aff001;  Dawit Tesfaye aff001;  Yousri Mohammed Shaker aff002;  Ernst Tholen aff001;  Christiane Neuhoff aff001;  Franca Rings aff003;  Eva Held aff001;  Michael Hoelker aff001;  Karl Schellander aff001;  Dessie Salilew-Wondim aff001
Působiště autorů: Institute of Animal Science, Department of Animal Breeding and Husbandry, University of Bonn, Bonn, Germany aff001;  Animal and Poultry Physiology Department, Animal and Poultry Production Division, Desert Research Center, Mataria, Cairo, Egypt aff002;  Teaching and Research Station Frankenforst, Faculty of Agriculture, University of Bonn, Königswinter, Germany aff003;  Center of Integrated Dairy Research, University of Bonn, Bonn, Germany aff004
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article
doi: https://doi.org/10.1371/journal.pone.0223753


Focal adhesion pathway is one of the key molecular pathways affected by suboptimal culture conditions during embryonic development. The epidermal growth factor (EGF) and hyaluronic acid (HA) are believed to be involved in the focal adhesion pathway function by regulating the adherence of the molecules to the extracellular matrix. However, regulatory and molecular mechanisms through which the EGF and HA could influence the embryo development is not clear. Therefore, this study aimed to investigate the effect of continued or stage specific supplementation of EGF and/or HA on the developmental competence and quality of bovine preimplantation embryos and the subsequent consequences on the expression and DNA methylation patterns of genes involved in the focal adhesion pathway. The results revealed that, the supplementation of EGF or HA from zygote to the blastocysts stage reduced the level of reactive oxygen species and increased hatching rate after thawing. On the other hand, HA decreased the apoptotic nuclei and increased blastocyst compared to EGF supplemented group. Gene expression and DNA methylation analysis in the resulting blastocysts indicated that, combined supplementation of EGF and HA increased the expression of genes involved in focal adhesion pathway while supplementation of EGF, HA or a combination of EGF and HA during the entire preimplantation period changed the DNA methylation patterns of genes involved in focal adhesion pathway. On the other hand, blastocysts developed in culture media supplemented with EGF + HA until the 16-cell stage exhibited higher expression level of genes involved in focal adhesion pathway compared to those supplemented after the 16-cell stage. Conversely, the DNA methylation level of candidate genes was increased in the blastocysts obtained from embryos cultured in media supplemented with EGF + HA after 16-cell stage. In conclusion, supplementation of bovine embryos with EGF and/or HA during the entire preimplantation period or in a stage specific manner altered the DNA methylation and expression patterns of candidate genes involved in the focal adhesion pathway which was in turn associated with the observed embryonic developmental competence and quality.

Klíčová slova:

Blastocysts – Culture media – DNA methylation – Embryos – Gene expression – Promoter regions – Focal adhesions – Zygotes


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