Use of retinyl acetate, retinoic acid and insulin-like growth factor-I (IGF-I) to enhance goat embryo production

Abstract

Experiments were carried out to investigate the beneficial effects of retinyl acetate (RAc) and retinoic acid (RA) on goat oocyte maturation as well as the effects of insulin-like growth factor-I (IGF-I), RAc and RA during embryo culture under chemically defined conditions. In Experiment 1, in vitro maturation (IVM) was performed in a chemically defined basic maturation medium (bMM) supplemented with 0.3 μM RAc or 0.5 μM RA. Presumptive zygotes and embryos (2-4 cells) were cultured in droplets of potassium simplex optimised medium (KSOM); however, none of the embryos reached the blastocyst stage. In Experiment 2, oocytes were matured in bMM + RAc or bMM + RA. Presumptive zygotes and 2- to 4-cell embryos were placed in fresh KSOM droplets supplemented with RAc, RA, IGF-I, RAc+IGF-I or RA+IGF-I. In Experiment 1, addition of RAc and RA to bMM increased (P < 0.05) the proportion of 2- to 4-cell embryos reaching the morula stage as compared to the control. In Experiment 2, supplementation of embryo culture media with retinoids and IGF-I increased (P < 0.05) the proportion of 2- to 4-cell stage embryos developing to the morula and blastocyst stage. Our data demonstrate that goat embryo production in chemically defined media could be improved by exogenous RAc or RA and by the interaction between retinoids and IGF-I, and that goat embryos can be produced in vitro from oocytes following protocols similar to those currently used for cattle.

Use of retinoids during oocyte maturation diminishes apoptosis in caprine embryos

“…Duque et al (2002b) reported that addition of 9-cis-retinoic acid is beneficial to embryonic development in a quantitative and qualitative manner. Similar results were described by Lima et al (2006) in bovine and Chiamenti et al (2010) in caprine embryos, due to the fact that retinoids synchronise cellular events that trigger oocyte maturation, increase oocyte ability to be fertilised and potentiate further preimplantation embryonic development (Duque et al, 2002a;Lima et al, 2004;Lima et al, 2006;Chiamenti et al, 2010Chiamenti et al, , 2013. However, Cavalcanti did not observe any effect of retinyl acetate or 9-cis-retinoic acid on caprine oocyte nuclear and cytoplasmatic maturation.…”

“…Retinoids, when supplemented during embryo culture, require co-culture systems, at least under some experimental conditions, in order to enhance embryonic development (Lima et al, 2004;Chiamenti et al, 2010Chiamenti et al, , 2013. This fact suggests that this paracrine signalling could be potentially useful for increasing embryonic development in vitro in other species and should be the focus of future research aimed at describing the molecular basis of retinoid embryotrophic properties in vitro.…”

“…More recently, technologies based on in vitro production (IVP) of caprine embryos have received increasing attention to further improve genetic gain in breeding schemes, and to generate cloned and/or transgenic goats (Keefer et al, 2001;Chiamenti et al, 2010Chiamenti et al, , 2013. Despite these advances, caprine IVP-based technologies are hampered by low efficiency (Bal-dassarre and Karatzas, 2004), which is partly due to the limited understanding of species-specific requirements for in vitro oocyte maturation, fertilisation, and embryo culture.…”

Antioxidant and developmental capacity of retinol on thein vitroculture of rabbit embryos

“…Retinoid compounds are found in the female reproductive tract and they were suggested to be able to improve the in vitro development of preimplantation embryos in several species (Duque et al , 2002a,b; Lima et al , 2004; Chiamenti et al , 2010, 2012). Retinoids are considered as a biological antioxidant network and an important regulators of redox signalling pathways (Ikeda et al , 2005; Alminana et al , 2008).…”

“…Recent protocols have used these compounds in the culture medium of embryos taking into account their deep effect upon cellular survival, proliferation, differentiation and embryonic morphogenesis (Noy, 2010; Rajesh et al , 2010; Rhinn & Dollé, 2012; Conceição et al , 2015; Conceição et al , 2016). It was found that the addition of retinoids to the culture medium enhances the subsequent preimplantation embryonic development in bovine embryos (Lima et al , 2004; Ahmed et al , 2016), and in goat embryos (Duque et al , 2002a,b; Lima et al , 2006; Chiamenti et al , 2010, 2012; Conceição et al , 2015). The positive effect of retinoids on embryo development could be induced directly by modulating growth factor gene expression or indirectly by improving the quality of mRNAs (Livingston et al , 2004).…”