Sat, 2012-11-17 15:29 | 
Finding solutions against the low blastocysts yield is the most challenging aspect of the research on in vitro animal embryo production. A poor embryo production is mainly attributed to divergent environmental and culture conditions compared to the in vivo ones. The presence or activity, of the proteolytic plasminogen activators/ plasmin system (PAA/PAI/PL) has been shown in many cells of the reproductive system, as well as in gametes and early embryos. Several studies have proved the involvement of the proteolytic system into oocyte maturation, fertilization, embryo development and implantation. However, these factors are practically absent from the standard culture media used in IVF labs. It has been previously shown in our lab (Papanikolaou et al 2008) that specific members of the PAA/PL system are all contributing to the development of in vitro produced bovine embryos, but each member of the system is acting differentially at each stage of IVP. Considering that in this study there is a positive effect on the IVF outcome by adding plasminogen activators into fertilization and culture medium, we extend our investigation to a later developmental stage of embryos (stage of blastocyst, 7-8 days post fertilization). At this stage, the embryo is ready to implant in the uterus which is very crucial for its survival. In other words, we investigate the possible effect of the addition of urokinase and tissue type plasminogen activators (uPA and tPA) into culture and fertilization medium, respectively. The assessment of the quantity, morphology and quality of produced embryos after media modification is expected to answer questions related to early embryonic development. To evaluate effects (positive or negative) of the activators, several genes have been selected and they will be used as quality markers. These genes are related to fundamental pathways controlling metabolism, apoptosis, oxidation and implantation, all of them being of paramount importance for the embryo survival. Real time PCR will be used to assess relative mRNA abundance of these genes. Last but not least, conventional freezing or vitrification of the produced embryos will enable us to conserve the treated embryos for future transfer to recipient cows, and to test the possible effects of our interventions to cryotolerance of produced blastocysts.
Ph.D Candidate:
Krania Fotini
Department:
Faculty of Veterinary Science
School:
School of Health Sciences
Supervisor:
Associate professor G.S Amiridis (gsamir@vet.uth.gr)
Supervising Committee:
(1) G.S Amiridis (2) J Pappas (3) C.A Rekkas Παραδοτέα έργου δημοσίως προσβάσιμα:
