Effects of meiotic inhibitors and gonadotrophins on porcine oocytes in vitro maturation, fertilization and development

Abstract

This study evaluated the effect of three reversible meiotic inhibitors (MINs) and their interaction with gonadotrophins (Gns) on the meiotic maturation and developmental competence of porcine oocytes. In experiment 1, the oocytes were matured for 22 hr in the presence or absence of dbcAMP (1 mM), cycloheximide (7 μM) or cilostamide (20 μM) with or without Gns, and for an additional 22 hr in the absence of MINs and Gns. At 22 hr of maturation, regardless of the presence of Gns, a higher proportion (p < .001) of oocytes cultured in the presence of MINs were effectively arrested at the germinal vesicle stage compared with the oocytes cultured without MINs. At 44 hr of maturation, the proportion of oocytes that reached MII was higher (p < .05) in groups with Gns compared with groups without Gns. In experiment 2, oocytes that were matured as in experiment 1 were inseminated and cultured for 7 days to evaluate fertilization parameters and blastocyst formation. Only oocytes from the dbcAMP + Gns group had higher (p < .05) efficiency of fertilization compared with the other treatment groups. The presence of dbcAMP during maturation also increased (p < .05) blastocyst formation and efficiency of blastocyst formation in both the presence and absence of Gns. These results indicate that the interaction of Gns with the tested MINs improved meiotic progression. In addition, regardless of supplementation with Gns, the presence of dbcAMP during the first maturation period increased and even doubled the capacity of oocytes to develop to the blastocyst stage.

Supplementation with exogenous coenzyme Q10 to media for in vitro maturation and embryo culture fails to promote the developmental competence of porcine embryos

“…However, we could speculate that the effect of the CoQ10 added to the IVM medium depends on the stress level to which the oocytes are exposed. The following arguments support this statement: firstly, a higher proportion of bovine oocytes (30%–50%), compared with porcine oocytes (10%–15%), die at the end of maturation (El‐Raey et al., ; Gil et al., ; Nabenishi et al., ), which indicates that the stress during IVM is greater in bovine than in porcine IVM cultures and that CoQ10 could improve some functions in the bovine oocytes leading to an increased percentage of alive and MII oocytes. Secondly, the proportion of bovine oocytes developing to the blastocyst stage is highest in winter, intermediate in fall and lowest in summer (Gendelman & Roth, ).…”

The effect of carbon monoxide on meiotic maturation of porcine oocytes

“…The block is then removed to allow the oocytes to mature under in vitro conditions (Vanhoutte et al, 2009;Gil et al, 2017;Leal et al, 2018). For example, temporarily arresting meiotic maturation by phosphodiesterase 3-inhibitor leads to an increase in oocyte quality and developmental potential (Vanhoutte et al, 2009;Gil et al, 2017;Leal et al, 2018). It would be an interesting question whether the application of CO to the culture system could lead to the synchronization of nuclear and cytoplasmic maturation.…”

Exogenous Melatonin in the Culture Medium Does Not Affect the Development of In Vivo-Derived Pig Embryos but Substantially Improves the Quality of In Vitro-Produced Embryos

“…The IVF medium consisted of Tris-buffered solution [ 42 ] supplemented with caffeine (2 mM) and bovine serum albumin (BSA; 0.2 mg/mL). The oocyte-sperm coincubation was performed as previously reported [ 43 ]. Briefly, groups of 30 denuded oocytes were incubated in 50 µL drops of IVF medium under paraffin oil at 38.5 °C with 5% CO 2 in the air and maximum humidity until sperm addition (approximately 30 min).…”