Effect of Temporary Meiotic Attenuation of Oocytes with Butyrolactone I and Roscovitine in Resistance to Bovine Embryos on Vitrification

Abstract

This study aimed to produce in vitro bovine embryos by the addition of two drugs, which is responsible for oocyte meiosis inhibition: roscovitine (ROS) and butyrolactone I (BL-I). Oocytes were recovered from slaughtered cows and matured in a commercial medium and maintained in a 5% CO2 atmosphere. Oocytes were maintained for 6 h in an in vitro maturation (IVM) medium containing ROS (12.5 μm), BL-I (50 μm) and association of drugs (ROS 6.25 μm and BL-I 25 μm). Oocytes were cultured for 18 h in an agent-free medium for the resumption of meiosis. After 24 h of maturation, oocytes were inseminated in the commercial in vitro fertilization (IVF) medium. Presumptive zygotes were cultured in SOFaa medium in a 5% CO2 atmosphere. On day 3, rate of cleavage was evaluated and on days 6 and 7, rate of blastocyst formation. BL-I and its association with the ROS increased the rates of cleavage and blastocyst formation (p < 0.05). The ROS alone was inefficient, impairing embryonic development, with low rates of blastocyst formation when compared to the control group and other treatments (p < 0.05). The embryos from BL-I and ROS+BL-I groups presented higher number of cells and lower rates of cellular apoptosis compared to other groups, either for the fresh or for post-thawing embryos. Embryos from ROS+BL-I group showed to be more resistant to the vitrification process, presenting a higher rate of embryonic re-expansion (p < 0.05). In conclusion, block of meiosis using BL-I or its association with ROS increased the rate of blastocyst formation, and the association of ROS+BL-I resulted in a better resistance to the embryo cryopreservation process.

Transient Arrest of Germinal Vesicle Breakdown Improved In Vitro Development Potential of Buffalo (Bubalus Bubalis) Oocytes

“…). A recent study has also concluded thatcombination of inhibitors is better not only in maintaining the oocytes at GV stage but also in improving their future development competence [Maziero et al, ].…”

Treatment with roscovitine and butyrolactone I prior to in vitro maturation alters blastocyst production

“…In each experimental group, oocytes were randomly collected at 6, 12 or 24 h of pre-IVM and 12, 18 or 24 h of IVM (n = 3058). Collection was performed as previously described by Maziero et al (2016).…”

“…Spontaneous oocyte maturation can be avoided by using specific cyclin-dependent kinase (CDK) inhibitors such as butyrolactone I (BL-I) and roscovitine (ROS), which inhibit activity of oocyte maturation promoting factor (MPF) (Adona et al, 2008;Quetglas et al, 2011;Maziero et al, 2016).…”

“…Such inhibitors have been added for 24 h to IVM medium, preserving bovine oocyte viability without compromising embryonic development (Kubelka et al, 2000;Lonergan et al, 2000;Mermillod et al, 2000;Ferreira et al, 2009;Quetglas et al, 2011). However, different usage times of these drugs have not been described in the literature (Maziero et al, 2016;Paschoal et al, 2017;Razza et al, 2018).…”

A Interferência Da Produção De Leite Nas Taxas De Recuperação Oocitária E Conversão Em Embriões De Doadoras Das Raças Gir E Meio Sangue

“…Para a fertilização in vitro (FIV) utilizou-se sêmen de um único touro da raça Holandês (diferentes partidas de congelação), descongelado por 30 segundos em banho-maria a 36 C°. Para a separação dos espermatozoides viáveis, realizou-se centrifugação em gradiente de Percoll (Maziero et al, 2016) e os oócitos foram incubados por 20 horas, em gotas de 10 μL com meio FIV (comercial da empresa), contendo até 30 oócitos/gota.…”