RESUMEN
This study aimed to evaluate the effect of two Embryo Manipulation Solutions (EMS and EMS supplemented) in maintenance of the viability of embryos, initially using structures derived from mice (first phase). Next, the efficiency of these solutions in routines of bovine embryo transfer was evaluated (second stage). Mice embryos were used in the stages of early blastocyst, and compact morula grades I and II. These embryos were initially randomly distributed and maintained for four hours in three solutions: Modified phosphate buffered saline (PBS; Control); EMS (treatment 1), and EMS supplemented (treatment 2). Subsequently, they were cultured in TCM 199 medium and evaluated in terms of total number of cells, morphometric characteristics, ultra structural aspects, detection of cell apoptosis, and quantification of Hsp70.3 gene expression. In the second phase, these same solutions were tested in the transfer of quality I and II bovine embryos (excellent and good). These embryos were transferred fresh to 58 recipients. The results showed that the total number of cells in embryos expanded blastocyst (ExB), the number of apoptotic cells, the cell, nuclear, nucleolar diameter and the nucleus/nucleolus ratio was similar among the treatments. The pregnancy rate shown on second phase was also similar. However, the EMS supplemented expressed more Hsp70.3 than EMS. The expression of Hsp70.3 was also greater for embryos in EMS than that of EMS supplemented. The McII embryos, EMS and EMS supplemented samples also expressed more Hsp70.3 compared to control embryos. In conclusion, the tested solutions can be used in routine embryo transfer techniques, replacing modified PBS solution as an effective media in maintaining embryo viability.
RESUMEN
O objetivo deste estudo foi investigar a influência da interação entre o Hormônio Folículo Estimulante obtido da pituitária Humana (hFSH; 10 ng/mL), Fator de Crescimento Semelhante a Insulina Tipo 1 (IGF-I; 100 ng/mL) e Tiroxina (T4 ; 10, 20 ng/mL) na sobrevivência, ativação e crescimento de folículos pré-antrais cultivados in vitro. Fragmentos do córtex ovariano coletados a partir de 17 cabras adultas não gestantes foram submetidos a diferentes tratamentos que incluíam meio α-MEM+, IGF-I, hFSH, T4 e em seguida foram processados para histologia clássica e microscopia eletrônica de transmissão. Os resultados demonstraram uma redução no percentual de folículos normais, após um e sete dias de cultivo nos meios α-MEM+ (controle cultivado), T4 (10)/IGF-I, T4 (20)/IGF-I/hFSH e nos meios α-MEM+, IGF-I/hFSH, T4 (20)/IGF-I/hFSH, T4 (20)/IGF-I/hFSH, quando comparados ao controle não cultivado. Entretanto, o meio contendo T4 (20)/hFSH apresentou taxa de sobrevivência folicular superior aos demais tratamentos, quando cultivado por sete dias. Observou-se, ainda, que o diâmetro folicular quando cultivado neste meio não se alterou, quando comparado ao controle (não cultivado). As análises ultraestruturais confirmaram a integridade de folículos cultivados em meio contendo T4 (20)/hFSH. Em conclusão, o meio com T4 (20)/hFSH apresentou os melhores resultados, quando se avaliou sobrevivência, crescimento e aspectos ultraestruturais de folículos pré-antrais de caprinos cultivados in vitro.
The aim of this study was to investigate the influence of the interaction between follicle stimulating hormone obtained from Human Pituitary (hFSH; 10 ng/mL), Insulin-like Growth Factor Type 1 (IGF-I; 100 ng/mL) and thyroxine (T4 ; 10, 20 ng/mL) on survival, activation and growth of preantral follicles (PAF) cultured in vitro. Fragments of ovarian cortex collected from 17 nonpregnant adult goats underwent different treatments that included α-MEM+ medium, IGF-I, hFSH, T4 and were processed for classic histology and transmission electron microscopy. The results showed a reduction in the percentage of normal follicles, after one and seven days of culture in media α-MEM+ (cultured control), T4 (10)/IGF-I, T4 (20)/IGF-I/hFSH and in media α-MEM+, IGF-I/hFSH, T4 (20)/IGF-I/hFSH, T4 (20)/IGF-I/hFSH, when compared to the non-cultured control. However, the medium containing T4 (20)/hFSH showed a follicular survival rate higher than the other treatments, when cultured for seven days. It was also observed that the follicular diameter did not change when cultured in this medium, when compared to the control (non-cultured). The ultrastructural analysis confirmed the integrity of follicles cultured in a medium containing T4 (20)/hFSH. In conclusion, the medium containing T4 (20)/hFSH showed the best results, when evaluating the survival, growth and ultrastructural aspects of caprine preantral follicles cultured in vitro.