Influence of vascular endothelial growth factor and Cysteamine on in vitro bovine oocyte maturation and subsequent embryo development

Abstract

The objective of this study was to investigate the effect of VEGF and Cysteamine during in vitro maturation (IVM) of bovine oocytes on GSH content and developmental competence. For this purpose, experiments were designed to evaluate the effect of 0, 100, 300, and 500 ng/mL VEGF in IVM medium on: GSH content in oocytes and cumulus cells (Exp. 1) and subsequent embryo development (Exp. 2). Also, influence of adding 500 ng/mL VEGF and 100 μM Cysteamine to IVM medium on GSH content in oocytes and cumulus cells (Exp. 3) and oocyte developmental capacity (Exp. 4) were evaluated. Oocytes were matured in: a) Control; b) VEGF 0-3 h; c) Cysteamine 4-24 h; d) VEGF 0-3 h + Cysteamine 4-24 h; and e) VEGF + Cysteamine 24 h. The results showed that: i) VEGF did not alter GSH content in oocytes and cumulus cells; (ii) supplementation of 300 and 500 ng/mL VEGF increased blastocyst yield; (iii) the presence of VEGF + Cysteamine simultaneously during 24 h improved GSH content but not embryo development; and (iv) the presence of VEGF during the first 3 h + Cysteamine from 4 to 24 h increased GSH concentrations and subsequent embryo development. In conclusion, the addition of VEGF and Cysteamine in two sequential steps to maturation medium result in an improvement of cytoplasmic maturation, with a positive impact on oocyte developmental capacity by increasing the efficiency of in vitro blastocyst production. However, the effect was detrimental when both VEGF and Cysteamine were present during 24 of IVM.

Presence of vascular endothelial growth factor during the first half of IVM improves the meiotic and developmental competence of porcine oocytes from small follicles

“…In the bovine, exposure of COCs derived from MF to 5 ng mL -1 VEGF during the first 20 h of IVM resulted in a higher percentage of matured oocytes, normal fertilisation and increased blastocyst yield, suggesting that VEGF may induce not only nuclear maturation, but also cytoplasmic maturation (Luo et al 2002). Similar results were reported recently with concentrations of 300-500 ng mL -1 VEGF (Anchordoquy et al 2015). Positive effects of VEGF have also been shown to promote the transition from primary to secondary follicles in the bovine (Yang and Fortune 2007) and to induce follicular growth and increase oocyte diameter in the goat (Bruno et al 2009 Therefore, in the present study we compared VEGF content of porcine COCs from MF and SF, as well as that secreted during IVM.…”

The blood vessels development, morphogenesis and blood circulation are three ontologic groups highly up-regulated in porcine oocytes before in vitro maturation

“…Li et al (2016) indicate improved quality and survival rate of subcutaneously-transplanted mouse ovarian tissue in VEGF coupled with FGF2-treated subjects [8]. Furthermore, IVM of bovine oocytes supplemented with VEGF results in an improvement of cytoplasmic maturation, with a positive impact on oocyte developmental capacity [9]. Our results indicate the lowest fold change of VEGFA transcript levels from all differentially ex- 18 TACR3 TACR3 19 TGFBR3 TGFBR3 20 TPM1 TPM1 21 VEGFA VEGFA VEGFA VEGFA TABLE 2 The list of differently expressed genes from the "blood circulation", "blood vessel development" and "blood vessel morphogenesis" ontology groups…”

“Positive Regulation of RNA Metabolic Process” Ontology Group Highly Regulated in Porcine Oocytes Matured In Vitro: A Microarray Approach

“…A study by Li et al indicates improved quality and survival rate of subcutaneously transplanted mouse ovarian tissue in VEGF coupled with FGF2-treated subjects [ 25 ]. Furthermore, in vitro maturation of bovine oocytes supplemented with VEGF results in an improvement of cytoplasmic maturation, with a positive impact on oocyte developmental capacity [ 26 ]. Early growth response (EGR) family members are highly homologous and contain conserved DNA-binding domain composed of three zinc-finger motifs [ 27 ].…”