RESUMO
The present study aimed to determine whether cumulus cells (CC) biopsy, acquired before or after in vitro maturation (IVM), presents similar gene expression pattern and if would compromises oocyte quality. First, immature cumulus oocyte complexes (COCs) were distributed: (1) maturated in groups (control); (2) individually maturated, but not biopsied; (3) subjected to CC biopsy before maturation and individually matured; (4) individually matured and submitted to CC biopsy after maturation; (5) individually matured and CC biopsied before and after maturation. Secondly, candidate genes, described as potential markers of COCs quality, were quantified by RT-qPCR in CCs before and after IVM. After in vitro fertilization (IVF), zygotes were tracked and sorted regarding their developmental potential: fully developed to embryo, cleaved and arrested, and not-cleaved. The COC's biopsy negatively affects embryo development (p < 0.05), blastocyst cell number (p < 0.05), and apoptotic cell ratio (p < 0.05), both before and after IVM. The PTGS2, LUM, ALCAM, FSHR, PGR, SERPINE2, HAS2, and PDRX3 genes were differentially expressed (p < 0.05) on matured CCs. Only PGR gene (p = 0.04) was under-expressed on matured CCs on Not-Cleaved group. The SERPINE2 gene was overexpressed (p = 0.01) in the Cleaved group on immature CCs. In summary, none of the selected gene studies can accurately predict COC's fate after fertilization.
RESUMO
Individual embryo culture is the only strategy that allows the tracking of embryos throughout the culture period. However, this procedure leads to lower embryo development. This study aimed to evaluate different alternatives to improve embryo development in a single in vitro production system. First, embryo production was compared between individual cultures on a 20 µL droplet and Cell-Tak® system. Then, various concentrations of folic acid were tested for use in combination with insulin-transferrin-selenium (ITS). To determine the concentration, embryos were analyzed not only by development but also by their methylation status. Finally, the supplementation of individual culture media with ITS and/or folic acid was evaluated. The results showed that embryos cultured in the Cell-Tak® system presented lower blastocyst rates than the microdroplets system. When the concentration of folic acid was tested, 20 µM and 500 µM presented a higher level of insulin-like growth factor (IGF2) DNA methylation pattern compared to control, suggesting that in vitro conditions alter DNA methylation pattern in that region and folic acid reestablishes the pattern. However, when it was used in an individual culture system, folic acid did not improve embryo development. Conversely, ITS which is composed of three important components, proved to be an alternative to individual embryo culture, improving embryo rates, showing similar rates to grouped culture embryos. Since Folic Acid change epigenetic profile, additional studies are needed to evaluate its use in IVP culture systems.
Assuntos
Técnicas de Cultura Embrionária , Selênio , Animais , Blastocisto , Bovinos , Meios de Cultura/farmacologia , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário , Fertilização in vitro/veterinária , Ácido Fólico/farmacologia , Insulina/farmacologia , Selênio/farmacologia , TransferrinaRESUMO
It is well-established that in vitro culture affects quality, gene expression, and epigenetic processes in bovine embryos and that trophectoderm cells are the most susceptible to abnormalities. These changes have been reported as the main factors responsible for losses observed after transfer of in vitro-produced embryos. The present study aimed to investigate the effect of an in vitro system on bovine embryo transcriptional profiles on D14 of development. Two groups were used-one with embryos produced in vitro until D7 (day 7; VT group) and another with embryos produced in vivo by hormonal stimulation, with embryos collected on D7 (VV group). D7 embryos at similar developmental stages from both treatments were transferred to recipient uteri and recollected on D14. From D14 embryos of both treatments, trophoblast samples were removed by biopsy for sexing and transcriptome analyses. Embryos were sexed by polymerase chain reaction (PCR), and only males were used for RNA sequencing. In total, 29,005 transcripts were expressed, from which 900 were differentially expressed, but only 29 genes were significantly differentially expressed. In addition, 20 genes were found uniquely for VV and 27 for VT. These findings suggested that although the uterine environment minimized transcriptional differences, it was not able to make trophoblasts from the in vitro embryos similar to the in vivo ones. The few genes exhibiting differences are in control of important events that may be responsible for embryonic losses occurring during the first period of gestation.
Assuntos
Desenvolvimento Embrionário/genética , Epigênese Genética/genética , Transcriptoma/genética , Trofoblastos/metabolismo , Animais , Blastocisto/metabolismo , Bovinos , Transferência Embrionária/métodos , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento/genética , RNA-SeqRESUMO
With a focus on productivity, Brazil has advanced research and application of reproductive biotechnologies. However, much remains to be explored, such as in vitro embryo production and transfer in miniature breeds. Thus, the objective of the present work is to report the in vitro production of miniature bovine embryos and transfer to conventional sized cows located in Palmas/To. Nine miniature Jersey-Holstein cross breed donors were aspirated to obtain approximately 13 viable oocytes per female. The oocytes were matured, fertilized and cultured the in vitro, where the production of viable embryos was 23.2%. On day 7 of development (D7) the embryos were transferred to 17 crossbred dairy recipients and after 30 days of innovulation by ultrasound examination a conception rate of 76.4% was found. Thus, the technique of in vitro production and embryo transfer is viable for the reproduction of mini dairy cows, despite the lack of data regarding the work performed on small animals that serve as comparative parameters for the results achieved in the study.(AU)
Assuntos
Animais , Feminino , Bovinos , Engenharia Genética/veterinária , Animais Geneticamente Modificados/embriologia , Fertilização in vitro , Transferência Embrionária/veterináriaRESUMO
With a focus on productivity, Brazil has advanced research and application of reproductive biotechnologies. However, much remains to be explored, such as in vitro embryo production and transfer in miniature breeds. Thus, the objective of the present work is to report the in vitro production of miniature bovine embryos and transfer to conventional sized cows located in Palmas/To. Nine miniature Jersey-Holstein cross breed donors were aspirated to obtain approximately 13 viable oocytes per female. The oocytes were matured, fertilized and cultured the in vitro, where the production of viable embryos was 23.2%. On day 7 of development (D7) the embryos were transferred to 17 crossbred dairy recipients and after 30 days of innovulation by ultrasound examination a conception rate of 76.4% was found. Thus, the technique of in vitro production and embryo transfer is viable for the reproduction of mini dairy cows, despite the lack of data regarding the work performed on small animals that serve as comparative parameters for the results achieved in the study.
Assuntos
Feminino , Animais , Bovinos , Animais Geneticamente Modificados/embriologia , Engenharia Genética/veterinária , Fertilização in vitro , Transferência Embrionária/veterináriaRESUMO
In an attempt to improve in vitro embryo production, we investigated the effect of FGF10 and 0.1 mM of cilostamide, cAMP modulator, during in vitro prematuration (PIVM) and in vitro maturation (IVM) on the developmental capacity of bovine oocytes. Five treatments (T) were used as follows: T1) IVM (control): COCs were matured for 22 h; T2) PIVM/IVM: COCs were submitted to 22 h of PIVM and 22 h of IVM; T3) PIVM + FGF10/IVM: COCs were submitted to PIVM for 22 h in the presence of FGF10 and matured for 22 h; T4) PIVM/IVM + FGF10: COCs were submitted to PIVM for 22 h and matured for 22 h in the presence of FGF10; and T5) PIVM + FGF10/IVM + FGF10: COCs were submitted to 22 h of PIVM and 22 h of IVM, both in the presence of FGF10. COCs were evaluated for CC expansion and nucleus configuration at 0 h, 22 h of PIVM and 22 h after IVM. At those time points, CCs were used for expression analysis of PTGS2, TNFAIP6, PTX3, HAS2, CASP8, CASP3, SLC2A1, SLC2A3 and FGFR2 genes. Then, embryo production was evaluated on D2 for cleavage and at D6, D7 and D8 for embryo development. Embryo quality was measured by the speed of development and by expression of KRT8, PLAC8, CD9, PAG2, PAG2, HSPB1, MSH6 genes. The percentage of COC that remained at GV after 22 h PIVM was lower (P < 0.05) in the treated group than in the control group, regardless of the addition of FGF10. Nevertheless at 22 h of maturation, none of the treatments affected the final rate of MII oocytes. No expansion of CCs was observed during the PIVM period. After 22 h of maturation expansion was similar (P > 0.05) for all groups but they all had lower expansion (P < 0.05) than control group. Except for PTGS2 and SLC2A1 which were unchanged during PIVM, all other genes changed their expression during PIVM. When we evaluated the changes in gene expression during IVM on the different groups, we noted a change in the expression of four genes (PTGS2, CASP8, PTX3 and TNFAIP6). No differences (P > 0.05) in the cleavage and blastocyst rates at D6 were observed among treatment groups. However, the blastocyst rates at D7 were lower (P < 0.05) than the control groups in which FGF10 was present either during PIVM or during IVM. When the speed of embryo development was evaluated on D7, embryos from groups PIVM-IVM and PIVM - IVM + FGF10 developed faster than the other groups. However, at D8, the hatching rate was similar (P > 0.05) for all groups. Of all the analysed genes, only PLAC8 was shown to be overexpressed in PIVM/IVM + FGF10, and MSH6 was less expressed (P < 0.05) in PIVM + FGF10/IVM + FGF10 group when compared with the control. According to these findings, the PIVM of COCs in the presence of FGF10 affected the molecular profile and the expansion of CCs without affecting the nuclear maturation and embryo production rates. Although the presence of FGF10 changed the expression of genes related to embryo quality it did not show a great impact when added either or both during PIVM and IVM.
Assuntos
Bovinos , Fator 10 de Crescimento de Fibroblastos/farmacologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/efeitos dos fármacos , Animais , Células do Cúmulo , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário , FemininoRESUMO
PURPOSE: In an attempt to improve in vitro embryo production, we investigated the effect of fibroblast growth factor 10 (FGF10) during in vitro maturation on the developmental capacity of bovine oocytes. MATERIAL AND METHODS: Cumulus-oocyte complexes (COCs) were aspirated from follicles of 3-8 mm diameter. After selection, the COCs were matured in medium with or without 0.5 ng/mL of FGF10. The effect of FGF10 during in vitro maturation (IVM) on nuclear maturation kinetics and expansion of the cumulus cells was investigated. Oocyte competence was assessed by the production and development speed of embryos and the relative expression of genes associated with embryo quality. RESULTS: FGF10 delayed the resumption of meiosis from 8 h onwards, but did not affect the percentage of oocytes reaching metaphase II, nor did it increase cumulus expansion at 22 h of maturation. We found no difference between treatments regarding embryo production, developmental speed, and gene expression. CONCLUSION: In conclusion, the presence of FGF10 during IVM had no effect on embryo production, developmental speed, and gene expression.
Assuntos
Desenvolvimento Embrionário/genética , Fator 10 de Crescimento de Fibroblastos/biossíntese , Técnicas de Maturação in Vitro de Oócitos , Oócitos/crescimento & desenvolvimento , Animais , Blastocisto/metabolismo , Bovinos , Células do Cúmulo/metabolismo , Técnicas de Cultura Embrionária , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Meiose/genética , Oócitos/metabolismoRESUMO
DNA methylation reprogramming occurs during mammalian gametogenesis and embryogenesis. Sex-specific DNA methylation patterns at specific CpG islands controlling imprinted genes are acquired during this window of development. Characterization of the DNA methylation dynamics of imprinted genes acquired by oocytes during folliculogenesis is essential for understanding the physiological and genetic aspects of female gametogenesis and to determine the parameters for oocyte competence. This knowledge can be used to improve in vitro embryo production (IVP), specifically because oocyte competence is one of the most important aspects determining the success of IVP. Imprinted genes, such as IGF2, play important roles in embryo development, placentation and fetal growth. The aim of this study was to characterize the DNA methylation profile of the CpG island located in IGF2 exon 10 in oocytes during bovine folliculogenesis. The methylation percentages in oocytes from primordial follicles, final secondary follicles, small antral follicles, large antral follicles, MII oocytes and spermatozoa were 73.74 ± 2.88%, 58.70 ± 7.46%, 56.00 ± 5.58%, 65.77 ± 5.10%, 56.35 ± 7.45% and 96.04 ± 0.78%, respectively. Oocytes from primordial follicles showed fewer hypomethylated alleles (15.5%) than MII oocytes (34.6%) (p = 0.039); spermatozoa showed only hypermethylated alleles. Moreover, MII oocytes were less methylated than spermatozoa (p<0.001). Our results showed that the methylation pattern of this region behaves differently between mature oocytes and spermatozoa. However, while this region has a classical imprinted pattern in spermatozoa that is fully methylated, it was variable in mature oocytes, showing hypermethylated and hypomethylated alleles. Furthermore, our results suggest that this CpG island may have received precocious reprogramming, considering that the hypermethylated pattern was already found in growing oocytes from primordial follicles. These results may contribute to our understanding of the reprogramming of imprinted genes during bovine oogenesis.
Assuntos
Bovinos/genética , Metilação de DNA , Impressão Genômica , Fator de Crescimento Insulin-Like II/genética , Oócitos/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Alelos , Animais , Ilhas de CpG , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Folículo Ovariano/metabolismoRESUMO
A criação de caprinos representa uma parcela expressiva na pecuária do estado do Piauí. A otimização da eficiência alimentar neste rebanho vem acarretando sérios problemas, devido ao manejo nutricional inadequado. Este procedimento tem como complicação, a urolitíase obstrutiva. Desta forma objetivando estudar a técnica de fistulização da bexiga como tratamento cirúrgico desta enfermidade, utilizou-se 10 caprinos machos adultos, clinicamente sadios. Os animais foram submetidos a tranquilização prévia com cloridrato de xilazina e anestesiados com cloridrato de lidocaína a 2%. Realizou-se uma incisão na região paramediana ventral do abdômen de 5 cm, onde a bexiga foi localizada e exteriorizada. Procedeu-se uma incisão de aproximadamente 1 cm, abrangendo toda camada muscular da bexiga, para formar a fístula. Estes animais foram observados durante 15 dias no qual a urina fluiu sem dificuldades. Ao final Concluiu-se que a técnica de fistulização da bexiga é uma alternativa no tratamento da urolitíase obstrutiva por não apresentar sérias complicações pós-operatórias e ser de fácil execução.
Goat raising in Piauí state represents an expressive part of the breeding of that State. Optimization of the alimentary efficiency in the drove have caused serious problems because of the inadequate feeding management. This procedure has a complicated result: the obstructive urolitiasis. Thus the aim of this work is to study bladder fistulization techniques as chirurgical treatment of this disease. It was used 10 male adult goats, clinically healthy. The animals were submitted previously to tranquillizer cloridrate of xylazine and anaesthetized with cloridrate of lydocaine 2 %. It was performed 5 centimeter incision in paramedian ventral region of the abdomen where bladder was localized and externalized. It was made an incision of approximately 1 centimeter and the whole bladder muscular layer was taken to make the fistula. These animals were observed during 15 days, in this period the micturition flow without difficulties. We concluded that bladder fistulization technique is an alternative to the obstructive urolitiasis treatment once no serious pos chirurgical complication is present and because of its simple execution.