123 EFFECTS OF TAURO URSODEOXYCHOLIC ACID ON DEVELOPMENT OF BOVINE EMBRYOS FROM IN VITRO FERTILIZATION

2015 ◽  
Vol 27 (1) ◽  
pp. 153 ◽  
Author(s):  
F. Lu ◽  
Z. Li ◽  
Z. Ruan ◽  
X. Liu ◽  
S. Du ◽  
...  

Endoplasmic reticulum stress (ERS) is a novel apoptotic pathway and plays an important role for embryonic development. Tauro ursodeoxycholic acid (TUDCA) is a specific chemical chaperone that can inhibit ERS. In this study, we investigated the effects of TUDCA on the development and mRNA expression of ERS-related genes in bovine embryos from IVF in order to improve the efficiency of embryo in vitro culture. Bovine oocytes collected from ovaries at slaughter were cultured in the maturation medium (TCM-199 + 26.2 mmol L–1 NaHCO3 + 5 mmol L–1 HEPES + 5% fetal bovine serum) for 24 h and fertilized in vitro with bovine sperm. After fertilization, the embryos were respectively placed into the medium (TCM-199 + 3% fetal bovine serum) containing different concentrations of TUDCA (0, 100, 250, 500, 1000 μmol L–1) and cultured in the 5% CO2 at 38.5°C. Blastocyst development was evaluated after 7 days of culture, and then the total cell number and apoptosis index of blastocysts were detected with TUNEL. In addition, X-box binding protein 1 (XBP-1) of embryos at 2-cell, 4-cell, morula, and blastocyst stages was detected with RT-PCR, and the change of the mRNA expression of ERS-related (Grp78, Ire1, Chop) and apoptosis-related (Bax, Bcl-2) genes in blastocyst collected at 7 days of culture were analysed by QRT-PCR. A total of 1336 oocytes were used in this study, and each experimental group comprised 6 replicates. The results revealed that the splicing of XBP-1 was present during the development of bovine embryos, and especially obvious at the 4-cell, morula, and blastocyst stages. When embryos were cultured in medium with different concentrations of TUDCA, compared with the control group (0 μmol L–1), more embryos developed to blastocyst stage with 500 μmol L–1 TUDCA (31.86 ± 7.32% v. 21.11 ± 8.05%; P < 0.05), but the cleavage rate was not significantly different among groups (P > 0.05). The result for TUNEL found that when adding 500 μmol L–1 TUDCA to culture, the bovine embryos significantly improved the total cell number of blastocysts (110. ± 15.21 v. 102.3 ± 8.62; P < 0.05), and the apoptosis index of blastocysts was markedly decreased (3.71 ± 0.91 v. 5.36 ± 1.92; P < 0.05) relative to the control group. Moreover, the result of QRT-PCR analysis showed that treating embryos with 500 μmol L–1 TUDCA significantly reduced the mRNA expression level of Ire1 and Chop genes (P < 0.05) and up-regulated the expression of anti-apoptotic Bcl-2 gene (P < 0.05), while down-regulated the expression of pro-apoptotic Bax gene (P < 0.05). Furthermore, XBP-1 splicing in blastocysts also abated after embryos were treated with 500 μmol L–1 TUDCA. In conclusion, ERS occurs in bovine embryos during in vitro culture, but treating embryos with 500 μmol L–1 TUDCA may reduce ERS to facilitate embryonic development. This work was funded by the China High Technology Development Program (2011AA100607), China Natural Science Foundation (31072033), and Guangxi Science Foundation (2011GXNSFA018084, 2012GXNSFFA060004).

2010 ◽  
Vol 22 (1) ◽  
pp. 307
Author(s):  
M. M. Souza ◽  
N. Z. Saraiva ◽  
C. S. Oliveira ◽  
T. A. D. Tetzner-Nanzeri ◽  
R. Vantini ◽  
...  

The use of fetal bovine serum (FBS) as protein supplementation in IVP of bovine embryos has presented difficulties because it can introduce a number of pathogenic components in culture systems, can be related to the birth of calf with abnormal growth and development, and precludes the establishment of the actual nutritional needs of the embryo, because it contains an unlimited variety of substances. This study evaluated the replacement of the FBS in the medium of in vitro culture (IVC) of bovine embryos, using the knockout serum replacer (KSR) as protein supplementation and culture medium conditioned with stem cells. Therefore, bovine oocytes from ovaries of slaughterhouse were selected and matured in vitro in TCM-199 medium supplemented with 10% FBS (Crypion), 1.0 μg mL-1 FSH (Pluset®, Calier, Barcelona, Spain), 50 μg mL-1 hCG (Profasi®, Serono, Geneva, Switzerland), 1.0 μg mL-1 estradiol (Sigma E-2758, Sigma Chemical, St. Louis, MO, USA), 0.2 mM sodium pyruvate, and 83.4 μg mL-1 amikacin for 24 h. After that, 1144 oocytes were fertilized in IVF-TALP medium containing 6 mg mL-1 of BSA. After 18 to 22 h, the zygotes were cultured in SOF + 5% FBS (group 2); SOF + 5% KSR (group 3); SOF (5% FBS) + 10% SOF (5% FBS) conditioned by stem cells (group 4); or SOF (5% KSR) + 10% SOF (5% KSR) conditioned by stem cells (group 5), in an atmosphere of 5% O2 at 38.5°C for 8 days. A control group outside the controlled atmosphere was added, supplemented with 5% FBS (group 1). The SOF medium supplemented with 5% FBS or KSR was conditioned by stem cells and added to SOF medium for the culture of embryo at a concentration of 10%. The rates of cleavage and production of blastocysts were assessed 48 hours and 7 days after IVF, respectively, and analyzed by chi-square test, with a significance level of 5% in the statistical program Minitab® (release 14.1, Minitab, State College, PA, USA). On the eighth day, the TUNEL test for determination of the percentage of apoptosis and the differential staining technique for determination of inner cell mass (ICM) and trophoblast (TF) were performed. The results were submitted to ANOVA, followed by comparing the means by Tukey’s test using the program GraphPad Prism (GraphPad, San Diego, CA, USA). The treatments did not differ in the production of embryos, being similar to the control group: G1 = 31.75% (74/233), G2 = 35.26% (79/224), G3 = 32.70% (74/226), G4 = 28.76% (63/219), and G5 = 26.85% (65/242). With regard to the assessment of embryonic quality, the treatments showed similar results to the control groups. No differences were observed among groups both in color and ICM/TF ratio (G1 = 0.60, G2 = 0.62, G3 =0.65, G4 = 0.60, and G5 = 0.60). Furthermore, the TUNEL showed no significant difference in the percentage of apoptosis among groups (G1 = 7.10%, G2 = 3.76%, G3 = 5.58%, G4 = 4.50%, and G5 = 4.11%). The data obtained so far indicate that it is possible to produce embryos in vitro by replacing the FBS in the culture, achieving results similar to those obtained with serum. Financial support: FAPESP 2007/58506-6.


2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4297
Author(s):  
Luciana Simões Rafagnin Marinho ◽  
Lain Uriel Ohlweiler ◽  
Marcos Henrique Barreta ◽  
Paulo Bayard Dias Gonçalves ◽  
Joana Claudia Mezzalira ◽  
...  

<p>Conjugated linoleic acid (CLA) might be able to improve the cryotolerance of <em>in vitro-</em>produced (IVP) embryos. The effect of two CLA isomers on the cryotolerance of bovine IVP embryos, as well as that of the stage of embryonic development and the method used for cryopreservation was evaluated by three experiments. In Experiment 1, oocytes (n = 3,917) were fertilized <em>in vitro </em>and cultured with 0, 50, 100, or 200 ?M <em>trans-</em>10<em>, cis-</em>12 (t10, c12 CLA). In Experiment 2, fertilized oocytes (n = 2,131) were cultured with 100 ?M t10, c12 or <em>cis-</em>9<em>, trans-</em>11 (c9<em>, </em>t11 CLA), or a combination of both isomers. The embryos were vitrified at the blastocyst (BL) or the expanded blastocyst (EB) stage. In Experiment 3, oocytes (n = 1,720) were fertilized and cultured with or without 100 ?M t10, c12 CLA, and the blastocysts were vitrified or frozen. Blastocyst development rate as well as the rates of re-expansion and hatching after thawing was recorded. Moreover, the mean cell number and mRNA expression of acetyl-CoA carboxylase (ACC1) and stearoyl-CoA desaturase (SCD1) as well as fatty acid synthase (FASN) multienzyme complex were determined. In Experiment 1, the highest concentration of t10, c12 CLA that did not reduce blastocyst development rate was 100 ?M. In Experiment 2, the rates of re-expansion and hatching among the EBs obtained through IVP after supplementation with t10, c12 CLA (73.1% and 57.7%), with c9, t11 CLA (80.0% and 68.6%), with the combination (78.3% and 52.2%), and with the control group (85.4% and 58.3%) were similar. At the BL stage, the rates of re-expansion and hatching were lower than those at the EB stage, and CLA combination allowed a hatching rate (8.0%) lower than that observed in the control group (40.0%). In Experiment 3, the hatching rates for vitrified EBs (vitrified control; 67.4%) and vitrified CLA EBs (65.8%) were higher than those obtained for frozen EBs, exposed (13.3%) or not exposed (28.6%) to CLA. In addition, in Experiment 3, the hatching rate was higher at the EB stage in vitrified groups, while the rates of BL and EB were similar in frozen groups, thus proving that vitrification was more efficient than freezing for IVP bovine embryos. In Experiment 3, CLA isomer t10, C12 did not influence the embryonic cell number or mRNA expression of ACC1 and SCD1 enzymes, but decreased the mRNA expression of FASN. In conclusion, 100 ?M CLA did not affect subsequent embryonic development. However, neither CLA isomer improved the cryotolerance of IVP bovine embryos.</p>


2018 ◽  
Vol 30 (1) ◽  
pp. 176
Author(s):  
M. M. R. Chowdhury ◽  
I. Khan ◽  
A. Mesalam ◽  
K.-L. Lee ◽  
J.-Y. Hwang ◽  
...  

In vitro embryo developmental potentials are still suboptimal compared with in vivo potential due to the challenge of various unknown stressors that must be overcome by in vitro-cultured oocytes. To improve existing embryo developmental potentials, many chemicals have been treated in maturation media by dissolving in toxic substances such as dimethyl sulfoxide (DMSO) or other carrier molecule. The foremost effort of this study was to investigate the impact of the solvent tetrahydrofuran (THF) on the cytotoxicity of in vitro embryo production (IVP). The experiment was completed within 8 replicates. Statistical analyses were performed using SPSS version 22.0 (IBM/SPSS, Armonk, NY, USA), a one-way ANOVA followed by multiple pairwise comparisons (Tukey’s test), and Duncan’s multiple range post hoc test. The level of statistical significance was considered P < 0.05. Oocytes were cultured in vitro maturation media (IVM) followed by in vitro fertilization (IVF), in vitro culture media 1 (IVC1), and in vitro culture media 2 (IVC2). Composition of the media was as follows: IVM medium was TCM-199 supplemented with 10% (v/v) fetal bovine serum, 1 µg mL−1 oestradiol-17β, 10 µg mL−1 FSH, 0.6 mM cysteine, and 0.2 mM sodium pyruvate. The IVC1 medium consisted of CR1-aa supplemented with 44 µg mL−1 sodium pyruvate, 14.6 µg mL−1 glutamine, 10 IU mL−1 penicillin, 0.1 mg mL−1 streptomycin, 3 mg mL−1 BSA, and 310 µg mL−1 glutathione. The IVC2 medium was the same composition as IVC1 except that BSA was replaced with 10% (v/v) fetal bovine serum. The final concentration of the optimized (0.5 µM) THF in culture medium was 0.4%. When coculturing with 0.5 µM THF in the IVM stage, the cleavage rate (58.65 ± 1.90% v. 56.87 ± 1.68%) was not significantly different, but the blastocyst rate (35.21 ± 1.44% v. 28.34 ± 2.11%) was significantly higher compared with the control group. The TUNEL assay confirmed that apoptotic nuclei in THF group were significantly reduced compared with the control group (2.32 ± 0.14 v. 5.65 ± 0.12). The total cell number of trophectoderm (TE) in control and THF groups was 115.34 ± 0.98 and 132.13 ± 1.55, and that of the inner cell mass (ICM) was 29.67 ± 0.40 and 39.94 ± 0.44, respectively. However, the ICM:TE ratio in control and treated blastocysts was 1:3.34 and 1:3.9, which was not statistically significant. Immunocytochemistry analysis (using antibodies to IKBKB, NFkB, COX2, CASP9, and CASP3) demonstrated that THF supplementation significantly attenuated expression of these proteins. The quantitative recerse transcription PCR data established that relative mRNA expression level of the anti-apoptotic gene BCL2 was up-regulated, whereas that of COX2, iNOS, BAX, IKBKB, NFkB, CASP9, and CASP3 were significantly down-regulated in the THF treated group compared with the control. In conclusion, 0.5 µM THF supplement in the IVM media did not have injurious effects on in vitro-cultured bovine embryos. This work was supported by grant from the Next-Generation BiogGeen21 (No. PJ01107703), IPET (No. 315017-5 and 117029-3), Allergy free cat (Co.. Felix Pets) and BK21plus.


2015 ◽  
Vol 27 (1) ◽  
pp. 155
Author(s):  
M. Barcelo-Fimbres ◽  
J. N. Gouze ◽  
N. R. Mtango ◽  
R. Koppang ◽  
J. P. Verstegen

Beneficial effects on embryonic development of co-culture with Vero cells during in vitro culture have been previously reported and related to Vero cells growth factors/cytokines secretion into the medium (1998 Human Reprod. 1600–1605). However, co-culture increases the probability of microorganism contamination during culture. In this study, we aimed to overcome this problem by culturing bovine embryos in conditioned medium derived from Vero cells culture (CM). Vero cells (GenBiotech, Antibes, France) were cultured for 24 h, and then the medium was removed, filtered, and frozen until its use. A total of 701 slaughterhouse bovine cumulus oocytes complexes were matured and fertilized in vitro under standard conditions. After fertilization, zygotes were allocated to 4 different treatments [0 (control), 5, 10, and 20% of CM v/v] for in vitro culture in BBH7 medium (BoviPro®, MOFA Global, Verona, WI, USA) at 38.5°C in 5% O2, 5% CO2, 90% N2 atmosphere for 7 days. A total of 8 replicates were done. Cleavage rates were assessed at 2.5 days, blastocyst rates and embryonic stage at 7 days, and blastocyst total cell number at 7.5 days after fertilization. Data were analysed by ANOVA using GLM; the percentages were transformed using arcsin square root. If the ANOVA was significant (P < 0.05), means were separated by Tukey's procedure using Statistix 10 software (Tallahassee, FL, USA). No differences in cleavage rates were found between treatments (P > 0.1; Table 1). However, the addition of conditioned medium at all levels increased the blastocyst production at Day 7 of culture (between 11 to 19 percentage points) compared with the control group (P < 0.01; Table 1); likewise, CM addition was superior in total embryo production (Day 7 morulae plus all blastocysts; P < 0.01; Table 1), between 12.5 to 15 percentage points higher than the control group. No differences were found between treatments for blastocyst total cell number at 7.5 days of culture (P > 0.1; Table 1) and overall embryonic developmental stage (P > 0.1; Table 1). In conclusion, we found a superior embryonic development when Vero cells conditioned medium was added at Day 0 of in vitro culture; the positive effect on total embryo production was observed even at 5% of conditioned medium. Table 1.Means (± s.e.m.) of embryonic development of bovine embryos


2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4297
Author(s):  
Luciana Simões Rafagnin Marinho ◽  
Lain Uriel Ohlweiler ◽  
Marcos Henrique Barreta ◽  
Paulo Bayard Dias Gonçalves ◽  
Joana Claudia Mezzalira ◽  
...  

Conjugated linoleic acid (CLA) might be able to improve the cryotolerance of in vitro-produced (IVP) embryos. The effect of two CLA isomers on the cryotolerance of bovine IVP embryos, as well as that of the stage of embryonic development and the method used for cryopreservation was evaluated by three experiments. In Experiment 1, oocytes (n = 3,917) were fertilized in vitro and cultured with 0, 50, 100, or 200 ?M trans-10, cis-12 (t10, c12 CLA). In Experiment 2, fertilized oocytes (n = 2,131) were cultured with 100 ?M t10, c12 or cis-9, trans-11 (c9, t11 CLA), or a combination of both isomers. The embryos were vitrified at the blastocyst (BL) or the expanded blastocyst (EB) stage. In Experiment 3, oocytes (n = 1,720) were fertilized and cultured with or without 100 ?M t10, c12 CLA, and the blastocysts were vitrified or frozen. Blastocyst development rate as well as the rates of re-expansion and hatching after thawing was recorded. Moreover, the mean cell number and mRNA expression of acetyl-CoA carboxylase (ACC1) and stearoyl-CoA desaturase (SCD1) as well as fatty acid synthase (FASN) multienzyme complex were determined. In Experiment 1, the highest concentration of t10, c12 CLA that did not reduce blastocyst development rate was 100 ?M. In Experiment 2, the rates of re-expansion and hatching among the EBs obtained through IVP after supplementation with t10, c12 CLA (73.1% and 57.7%), with c9, t11 CLA (80.0% and 68.6%), with the combination (78.3% and 52.2%), and with the control group (85.4% and 58.3%) were similar. At the BL stage, the rates of re-expansion and hatching were lower than those at the EB stage, and CLA combination allowed a hatching rate (8.0%) lower than that observed in the control group (40.0%). In Experiment 3, the hatching rates for vitrified EBs (vitrified control; 67.4%) and vitrified CLA EBs (65.8%) were higher than those obtained for frozen EBs, exposed (13.3%) or not exposed (28.6%) to CLA. In addition, in Experiment 3, the hatching rate was higher at the EB stage in vitrified groups, while the rates of BL and EB were similar in frozen groups, thus proving that vitrification was more efficient than freezing for IVP bovine embryos. In Experiment 3, CLA isomer t10, C12 did not influence the embryonic cell number or mRNA expression of ACC1 and SCD1 enzymes, but decreased the mRNA expression of FASN. In conclusion, 100 ?M CLA did not affect subsequent embryonic development. However, neither CLA isomer improved the cryotolerance of IVP bovine embryos.


2005 ◽  
Vol 17 (2) ◽  
pp. 280 ◽  
Author(s):  
K. Yoshioka ◽  
C. Suzuki ◽  
H. Rodriguez-Martinez

Porcine embryos, derived from in vitro maturation and fertilization, were used to investigate the effects of timing of serum inclusion and PVA replacement in the medium for in vitro culture (IVC) on rates of blastocyst formation and hatching. In Experiment 1, presumptive zygotes at 20 h post-insemination (hpi) or cleaved embryos obtained by culture in porcine zygote medium (PZM-5) containing 3 mg mL−1 polyvinyl alcohol (PVA) at 48 or 96 hpi were further cultured in either PZM-5 containing PVA or PZM-5 where PVA was replaced by 1%, 5%, or 10% fetal bovine serum (FBS) until Day 6 (Day 0 = the day of in vitro insemination). Supplementation with 1% to 10% FBS at 20 and 48 hpi reduced (P < 0.05; by ANOVA and Fisher's PLSD test) blastocyst rates on Days 5 (0% to 1%) and 6 (3% to 6%) compared with PVA supplementation (4% and 22%, respectively). However, addition of 10% FBS at 96 hpi increased (P < 0.05) blastocyst rates (30%) on Day 5 compared with PVA (11%) and 1% FBS (15%); there was no significant difference among treatments in rates of blastocyst formation on Day 6 (24% to 40%). The total number of blastomeres in Day 6 blastocysts did not differ among treatments at any timing of serum supplementation (26.5 to 48.3 cells). In Experiment 2, presumptive zygotes were cultured from 20 to 96 hpi in PVA medium, and the cleaved embryos were later transferred into PZM-5 containing PVA, or 1%, 5%, or 10% FBS for another 4 days. Hatching rates of embryos on Days 7 and 8 were significantly higher (P < 0.05) in PZM-5 where PVA was replaced with 10% FBS (15% and 20%, respectively) than those in PZM-5 containing PVA (1% and 5%, respectively). Moreover, the total cell number in hatching/hatched blastocysts on Day 8 were significantly greater (P < 0.05) in medium containing 10% FBS (135.1 cells) than that in PVA medium (77.0 cells). In Experiment 3, at 130 hpi, blastocysts derived from IVC with PZM-5 containing PVA were transferred into PZM-5 containing PVA, 3 mg mL−1 bovine serum albumin (BSA) or 10% FBS for another 2 days. Hatching rates of blastocysts on Days 6, 7 and 8 were significantly higher (P < 0.05) in PZM-5 where PVA was replaced with 10% FBS (12%, 56%, and 64%, respectively) than those in PZM-5 containing PVA (0%, 12%, and 20%, respectively) and BSA (0%, 12%, and 20%, respectively). Moreover, the total cell number in hatching/hatched blastocysts on Day 8 were significantly greater (P < 0.05) in medium containing 10% FBS (138.7 cells) than that in PVA (71.7 cells) and BSA medium (70.7 cells). The results indicate that the timing of serum inclusion in the culture medium markedly affects porcine embryo development in vitro and that replacement of PVA with FBS in PZM-5 at 96 hpi or later improves the subsequent development of embryos to the hatching/hatched blastocyst stage. This work was supported by MAFF, Japan, and STINT and FORMAS, Sweden.


Zygote ◽  
2016 ◽  
Vol 24 (6) ◽  
pp. 890-899 ◽  
Author(s):  
A.L.S. Guimarães ◽  
S.A. Pereira ◽  
M. N. Diógenes ◽  
M.A.N. Dode

SummaryThe aim of this study was to evaluate the effect of adding a combination of insulin, transferrin and selenium (ITS) and l-ascorbic acid (AA) during in vitro maturation (IVM) and in vitro culture (IVC) on in vitro embryo production. To verify the effect of the supplements, cleavage and blastocyst rates, embryo size and total cell number were performed. Embryonic development data, embryo size categorization and kinetics of maturation were analyzed by chi-squared test, while the total cell number was analyzed by a Kruskal–Wallis test (P < 0.05). When ITS was present during IVM, IVC or the entire culture, all treatments had a cleavage and blastocyst rates and embryo quality, similar to those of the control group (P < 0.05). Supplementation of IVM medium with ITS and AA for 12 h or 24 h showed that the last 12 h increased embryo production (51.6%; n = 220) on D7 compared with the control (39.5%; n = 213). However, no improvement was observed in blastocyst rate when less competent oocytes, obtained from 1–3 mm follicles, were exposed to ITS + AA for the last 12 h of IVM, with a blastocyst rate of 14.9% (n = 47) compared with 61.0% (n = 141) in the control group. The results suggest that the addition of ITS alone did not affect embryo production; however, when combined with AA in the last 12 h of maturation, there was improvement in the quantity and quality of embryos produced. Furthermore, the use of ITS and AA during IVM did not improve the competence of oocytes obtained from small follicles.


Zygote ◽  
2009 ◽  
Vol 17 (1) ◽  
pp. 57-61 ◽  
Author(s):  
M. Popelková ◽  
Z. Turanová ◽  
L. Koprdová ◽  
A. Ostró ◽  
S. Toporcerová ◽  
...  

SummaryThe aim of the study was to determine the efficiency of two vitrification techniques followed by two assisted hatching (AH) techniques based on post-thaw developmental capacity of precompacted rabbit embryos and their ability to leave the zona pellucida (hatching) during in vitro culture. The total cell number and embryo diameter as additional markers of embryo quality after warming were evaluated. In vivo fertilized, in vitro cultured 8–12-cell rabbit embryos obtained from superovulated rabbit does were cryopreserved by two-step vitrification method using ethylene glycol (EG) as cryoprotectant or by one-step vitrification method with EG and Ficoll (EG+Ficoll). Thawed embryos were subjected to enzymatic or mechanical AH. Vitrified EG group showed significantly lower (P < 0.05) blastocyst rate (22.5%) and hatching rate (15%) than those vitrified with EG + Ficoll (63 and 63% resp.) and that of control (97 and 97% respectively). Significantly lower values of total cell number (P < 0.05) as well as embryo diameter (P < 0.01) in EG group compared with EG + Ficoll and control group were recorded. No significant difference was found in developmental potential of warmed embryos treated by either mechanical or enzymatic AH. The present study demonstrates that the EG + Ficoll vitrification protocol provides superior embryo survival rates over the EG vitrification protocol for 8–12-cell stage precompacted rabbit embryos. No positive effect of either mechanical or enzymatic AH on the post-thaw viability and quality of rabbit embryos in vitro was observed.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 327-328
Author(s):  
Galina Singina

Abstract The oocyte quality acquired during in vitro maturation (IVM) are the main limitative factors affecting the embryo production. The aim of the present research was to study effects of fibroblast growth factor 2 (FGF2) and insulin-like growth factor 1 (IGF1) during IVM of bovine oocytes on their developmental potential after parthenogenetic activation. Bovine cumulus-oocyte complexes (COC; n = 1176) were cultured for 22h in either standard maturation medium (TCM-199 supplemented with 10% fetal calf serum (FCS), 0.2 mM sodium pyruvate, 10 μg/ml FSH and 10 μg/ml LH; Control) or maturation medium supplemented with different concentrations (5–160 ng/ml) of FGF2 and IGF1. After IVM, matured oocytes activated by sequential treatment with ionomycin followed by DMAP and cyclohexamide and then cultured up to the blastocyst stage. The obtained blastocysts were fixed, and the total cell number and the level of apoptosis were determined using DAPI and TUNEL staining. The data from 4 replicates (77–91 oocytes per treatment) were analyzed by ANOVA. Cleavage rates of activated oocytes did not differ between groups and ranged from 63.7 to 68.1%. The addition of 10, 20 and 40 ng/ml of FGF2 to the IVM medium led to an increase in the yield of blastocysts [from 19.6±1.8% (Control) to 35.2±3.4, 29.8±1.9 and 31.1±2.1%, respectively (P&lt;0.05)] and in the total cell number in embryos that developed to the blastocyst stage (P&lt;0.05). Meanwhile, the blastocyst yield and the total cell number in blastocysts in the IGF1-treated groups were similar to that in the control group. No effects of both growth factors on the proportion of apoptotic nuclei in blastocysts (5.3–7.1%) were observed. Thus, FGF2 (but not IGF1) are able to maintain competence for parthenogenetic development of bovine COC during their maturation invitro. Supported by RFBR (18-29-07089) and the Ministry of Science and Higher Education of Russia.


2009 ◽  
Vol 21 (1) ◽  
pp. 148
Author(s):  
D. N. Q. Thanh ◽  
K. Matsukawa ◽  
M. Kaneda ◽  
S. Akagi ◽  
Y. Kanai ◽  
...  

In the mouse, single blastomeres of the 2-cell embryos can develop into adult mice and occasionally both separated blastomeres can give rise to twin animals (reviewed by Tarkowski AK et al. 2001 Int. J. Dev. Biol. 45, 591–596). As a preliminary study for production of monozygotic twins from porcine 2-cell embryos, we investigated the effects of removal of zona pellucida and blastomere isolation at the 2-cell stage on subsequent development of parthenogenetic embryos. Oocytes with the first polar body were parthenogenetically activated after 44 h of in vitro maturation. Stimulated oocytes were then incubated in IVC-PyrLac (IVC medium with pyruvate and lactose) according to the method reported by Kikuchi K et al. (2002 Biol. Reprod. 66, 1033–1041). After 24 to 30 h of parthenogenetic activation, equally cleaved 2-cell embryos were selected and used for the experiments. Some 2-cell embryos were then treated with pronase to remove the zona pellucida and cultured individually as zona-free 2-cell embryos having 2 blastomeres in pair (ZF group), and single blastomeres were split from ZF group and cultured separately (SB group) in V-shaped microwells. In addition, intact 2-cell embryos were cultured individually without pronase treatment as a control group. After 24 h of in vitro culture, IVC-PyrLac was replaced by IVC-Glu (IVC with glucose). The blastocyst rates on Day 6 (Day 0 was defined as the day of electrical stimulation) in control, ZF, and SB groups did not differ (47.6, 50.0, and 42.1%, respectively). Nevertheless, blastocysts derived from the ZF (28.6 ± 3.0) and SB groups (25.9 ± 1.3) had a significantly lower total cell number than that of the control group (41.7 ± 3.2; P < 0.01 by ANOVA). Although the total cell number of blastocysts originating from single blastomeres was significantly lower than that in the intact embryos, the blastocyst formation rates were not different between them. This indicated the possibility of production of monozygotic twins from porcine 2-cell embryos divided into 2 single blastomeres. However, further research is needed to improve blastocyst quality descended from single blastomeres. In conclusion, the removal of the zona pellucida had a negative influence on blastocyst quality but did not affect the development of porcine embryos to the blastocyst stage.


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