282 DIFFERENT CONCENTRATIONS OF FORSKOLIN FOR MEIOSIS BLOCK AND TO IMPROVE IN VITRO PRODUCTION OF BOVINE EMBRYOS

2015 ◽  
Vol 27 (1) ◽  
pp. 230
Author(s):  
D. Paschoal ◽  
R. Maziero ◽  
M. Sudano ◽  
M. Guastali ◽  
L. Crocomo ◽  
...  

The inhibition of nuclear maturation allows time for the oocyte to accumulate molecules that are important for embryonic development. It was suggested that the inhibition of spontaneous nuclear IVM might allow for more time to accumulate the molecules important for embryonic development. The objective of this work was to evaluate blocking oocyte meiosis with the addition of forskolin. Slaughterhouse-derived bovine Zebu ovaries were collected and carried to the laboratory. Oocytes (n = 584) with at least 3 intact layers of cumulus cells and homogeneous cytoplasm were selected for IVM. The oocytes were transferred to drops of TCM 199 plus 10% FCS and hormones. The oocytes remained in IVM medium in 3 different concentrations of forskolin (6886), 0.1, 0.05, 0.025 mM, and a control group (withouth forskolin), for 6 h. Then they were maturated for an additional 18 h in forskolin-free medium. The first period above was an attempt to block (Block) and the second to resume (Res) the oocyte meiosis. The oocytes were incubated in a humidified atmosphere with 5% CO2 at 38.5°C in an air incubator. The oocytes were assessed for the stage of nuclear maturation, to see if they were in M II. Then oocytes were in vitro fertilized (IVF) with frozen Nelore bull semen (Bos taurus indicus). Presumptive zygotes (20–30/group) were cultured in SOFaa (synthetic oviducal fluid) supplemented with 5 mg mL–1 of BSA; the embryos were kept in an incubator with 5% CO2, 5% O2, and 90% N2 at 38.5°C and absolute humidity. On Day 7 (Day 0 = IVF) the blastocyst, the number of viable cells, and apoptosis rate (terminal deoxynucleotide transferase uridine nick-end labelling) were observed. Data were analysed with ANOVA using SAS PROC GLM (SAS Inst. Inc., Cary, NC, USA). Sources of variation in the model, including treatment and replication, were respectively considered fixed and random effects. If ANOVA was significant, the contrasts of means were performed using the least-squares difference. Data are presented as the mean and the standard error of least-squares. For all analyses, we used a significance level of 5%. No differences were observed for the stage of nuclear maturation of the oocyte (N = 336; control: 67.7 ± 8.3; F 0.025 mM, Block/Res: 67.7 ± 8.9; F 0.05 mM, Block/Res: 65.9 ± 9.8; F 0.1 mM, Block/Res: 50.2 ± 8.9), the blastocyst rate (N = 584; Control: 36.7 ± 3.7; F0.025 mM, Block/Res: 32.6 ± 3.7; F0.05 mM, Block/Res: 29.2 ± 3.7; F0.1 mM, Block/Res: 25.1 ± 3.7), and total number of intact cells (N = 10–15 embryos/group; Control:140.1 ± 13.0; F0.025 mM, Block/Res: 129.9 ± 13.0; F0.05 mM, Block/Res: 139.0 ± 13.0; F0.1 mM, Block/Res: 104.4 ± 13.0; P > 0.05). However, a higher rate of apoptosis was observed in the blastocysts produced from oocytes blocked for 6 h with the higher concentration of forskolin (N = 10–15 embryos/group): Control: 12.1 ± 2.5a; F 0.025 mM, Block/Res: 12.9 ± 2.5a; F0.05 mM, Block/Res: 13.5 ± 2.5a; F 0.1 mM, Block/Res: 30.2 ± 2.5b (P < 0.05). We conclude that all the experimental groups reached the stage of M II after the addition of forskolin and the highest concentration of forskolin caused cellular degeneration without harming embryo production on the seventh day.

2019 ◽  
Vol 31 (1) ◽  
pp. 207
Author(s):  
L. Schefer ◽  
K. R. L. Schwarz ◽  
H. Fernandes ◽  
D. M. P. Paschoal ◽  
F. C. C. Castro ◽  
...  

One of the difficulties still observed in in vitro production (IVP) of bovine embryos is the lower cryotolerance of such embryos, which has been related to their increased lipid accumulation during culture in the presence of fetal bovine serum (FBS). Previous studies have indicated that the cyclic guanosine monophosphate (cGMP) pathway may be involved in the lipid metabolism of bovine cumulus-oocyte complexes (COC). Synthesis of cGMP can be caused by activation of membrane guanylate cyclase (mGC), also called natriuretic peptide receptors (NPR1 and NPR2), which are activated by natriuretic peptides (NP) A, B, and C types (NPPA, NPPB, and NPPC). The objective of this study was to investigate the influence of supplementation with NP during in vitro maturation (IVM) on lipid content and nuclear maturation of bovine COC. Pools of 25 COC were submitted to IVM in TCM-199 with 0.2mM sodium pyruvate, 10μg mL−1 gentamicide, 0.5μg mL−1 FSH, 10% FBS, and NPPA (10−5 M), NPPB (10−7 M), or NPPC (10−5 M). The control group was matured without NP. After 24h, cumulus cells (CC) were removed and oocytes (OO) were fixed and permeabilized in 4% paraformaldehyde+0.5% Triton for 20min, stained with 10μg mL−1 Hoechst 33342 for 15min and 1μg mL−1 Nile Red for 30min. Then, the OO were placed in 13μL of ProLong (Thermo Fisher Scientific, Waltham, MA, USA) on glass slides, covered with a coverslip, and submitted to epifluorescence microscopy to evaluate nuclear maturation (emission 445-450nm and excitation 475-490nm) and lipid content (emission 590nm and excitation 516-560nm). Data for 4 replicates/group were tested for normality of results and homogeneity of variance, and then submitted to ANOVA, followed by Tukey test using a GraphPad Prism software (GraphPad Inc., San Diego, CA, USA), with a significance level of 5%. Nuclear maturation was influenced only by one of the NP added to IVM medium, NPPC, which reduced maturation rate (68.3% metaphase II, MII) compared with the control (82.7% MII; P&lt;0.05). Maturation rates of NPPA (79.5% MII) and NPPB (85.1% MII) did not differ from the control (P&gt;0.05). Activation of mGC by NPPB generated oocytes with lower lipid content (34.02±1.2 IF/μm2) compared with control (36.98±0.7 IF/μm2; P&lt;0.05). Neither NPPA (36.5±1.4 IF/μm2) nor NPPC (39.3±1.4 IF/μm2) was able to reduce the lipid content in oocytes matured in vitro relative to control (P&gt;0.05). Different NP may have different effects on maturation and lipid content in in vitro matured bovine oocytes; NPPB may be favourable for reducing the lipid content of matured bovine oocytes in vitro.


Zygote ◽  
2019 ◽  
Vol 28 (1) ◽  
pp. 24-31 ◽  
Author(s):  
Rosiara Rosária Dias Maziero ◽  
Carlos Renato de Freitas Guaitolini ◽  
Daniela Martins Paschoal ◽  
André Maciel Crespilho ◽  
Bianca Andriolo Monteiro ◽  
...  

SummaryThis study evaluated the effects of oocyte meiosis inhibitors roscovitine (ROS) and butyrolactone I (BL-I) on in vitro production of bovine embryos. Bovine oocytes were maintained in pre in vitro maturation (pre-IVM) with 25 µM ROS or 100 µM BL-I for 24 h to delay meiosis and for 24 h in in vitro maturation (IVM). Following this treatment, the nuclear maturation index was evaluated. All embryos degenerated following this procedure. In the second set of experiments, oocytes were maintained for 6 or 12 h in pre-IVM with the following three treatments: ROS (25 µM or 12.5 µM), BL-I (100 µM or 50 µM) or a combination of both drugs (6.25 µM ROS and 12.5 µM BL-I). Oocytes were cultivated for 18 or 12 h in IVM. When a meiosis-inducing agent was used during pre-IVM for 24 h, more degenerated oocytes were observed at the end of the IVM period. This effect decreased when the meiotic blocking period was reduced to 6 or 12 h. No significant differences were observed in the blastocyst production rate of oocytes in pre-IVM for 6 h with ROS, BL-I, or ROS + BL-I compared with that of the control group (P > 0.05). However, inhibition of oocytes for 12 h resulted in decreased embryo production compared with that in the controls (P < 0.05). There was no difference in the post-vitrification embryo re-expansion rate between the study groups, showing that the meiotic inhibition for 6 or 12 h did not alter the embryo cryopreservation process.


Zygote ◽  
2020 ◽  
pp. 1-6
Author(s):  
Ji-Eun Park ◽  
Sang-Hee Lee ◽  
Yong Hwangbo ◽  
Choon-Keun Park

Summary The aim of the present study was to investigate the effects of porcine follicular fluid (pFF) from large-sized (LFF; >8 mm in diameter) and medium-sized (MFF; 3–6 mm in diameter) follicles on the maturation and developmental competence of porcine oocytes. Cumulus–oocyte complexes (COCs) were collected from follicles 3–6 mm in diameter. The collected COCs were incubated for 22 h with LFF or MFF (in vitro maturation (IVM)-I stage) and were incubated subsequently for 22 h with LFF or MFF (IVM-II stage). Cumulus expansion was confirmed after the IVM-I stage and nuclear maturation was evaluated after the IVM-II stage. Intracellular glutathione (GSH) and reactive oxygen species (ROS) levels were measured and embryonic development was evaluated. Relative cumulus expansion and GSH levels were higher in the LFF group compared with in the MFF group after the IVM-I stage (P < 0.05). After the IVM-II stage, the numbers of oocytes in metaphase-II were increased in the LFF group and GSH content was higher in all of the LFF treatment groups compared with in the MFF treatment groups during both IVM stages (P < 0.05). ROS levels were reduced by LFF treatment regardless of IVM stage (P < 0.05). Blastocyst formation and the total numbers of cells in blastocysts were increased in all LFF treatment groups compared with the control group (P < 0.05). These results suggested that pFF from large follicles at the IVM stage could improve nucleic and cytoplasmic maturation status and further embryonic development through reducing ROS levels and enhancing responsiveness to gonadotropins.


Zygote ◽  
2015 ◽  
Vol 24 (2) ◽  
pp. 161-171 ◽  
Author(s):  
Daniela Martins Paschoal ◽  
Rosiára Rosária Dias Maziero ◽  
Mateus José Sudano ◽  
Midyan Daroz Guastali ◽  
Luis Eduardo Vergara ◽  
...  

SummaryThe inhibition of nuclear maturation allows time for the oocyte to accumulate molecules that are important for embryonic development. Thus, the objective of this work was to evaluate the effect of blocking oocyte meiosis with the addition of forskolin, an efficient inhibitor of nuclear maturation, in in vitro maturation (IVM) medium. Forskolin was added to the IVM medium for 6 h at concentrations of 0.1 mM, 0.05 mM or 0.025 mM, then the oocytes were allowed to mature in drug-free medium for 18 h. The oocytes were assessed for the stage of nuclear maturation, the activity and distribution of mitochondria, oocyte ultrastructure, the number of viable cells and the apoptosis rate. After forskolin treatment, the oocytes were fertilized in vitro and cultured for 7 days. On day 7, the blastocyst rate, the ultrastructure, the number of intact cells and the apoptosis rate of the blastocysts were measured. No differences were observed for the stage of nuclear maturation of the oocyte, the mitochondrial activity and distribution, the blastocyst rate or total number of intact cells. However, a higher rate of apoptosis was observed in the blastocysts produced from oocytes blocked for 6 h with the higher concentration of forskolin (P < 0.05). We conclude that all the experimental groups reached the MII stage after the addition of forskolin and that the highest concentration of forskolin caused cellular degeneration without harming embryo production on the 7th day.


2010 ◽  
Vol 22 (1) ◽  
pp. 236
Author(s):  
T. A. D. Tetzner ◽  
N. Z. Saraiva ◽  
C. S. Oliveira ◽  
S. C. Méo ◽  
M. M. Souza ◽  
...  

Embryo quality is influenced by culture conditions, which affect IVM, IVF, and IVC rates. One of the most efficient ways to evaluate the embryonic quality of IVP blastocysts is by differential staining of inner cell mass (ICM) and trophoblast (TF). Bovine embryos of superior quality should present the total number of cells close to the number of cell cycles (Neuber et al. 2002 Theriogenology 57, 2193-2202). In this study, we analyzed the effects of fetal bovine serum (F) and bovine serum albumin (B) replacement for ovalbumin (O) on nuclear maturation, cortical granule migration, pronuclear development, blastocyst rates, and differential staining of ICM and TF in Day 7 blastocysts. The treatment groups were named as follows: the first letter is the protein source used for IVM, the second for IVF, and the third for IVC. When 2 protein sources were used in the same step, the plus symbol (+) was used. The oocytes were IVM in TCM-199, supplemented with the following: 10% F, or 4 mg mL-1 B, or 4 mg mL-1 O, and 1.0 Âμg mL-1 of FSH, 50 Âμg mL-1 of hCG, 1.0 Âμg mL-1 of estradiol, 0.2 mM sodium pyruvate, and 83.4 Âμg mL-1 of amikacin. IVF was accomplished in TALP-IVF medium, with 0.2 mM pyruvate, 83.4 Âμg mL-1 of amikacin, and 6 mg mL-1 B or O. IVC was in SOF, with F, B, or O. The control group (CONT) consisted of the treatment FBF + B. Pronuclear development was compared by the chi-square test, whereas the other results were analyzed by ANOVA followed by the Tukey test, using SAS at 5% significance level (SAS Institute Inc., Cary, NC, USA). For IVM, the treatments F, B, O, and B + O did not affect (P > 0.05) nuclear maturation (73.92 to 78.78%) and cortical granule migration rates (58.89 to 66.76%). Regarding pronuclear development, the treatment FO (76.67%) was similar (P > 0.05) to the control group (82.95%), which was superior (P < 0.05) to the treatments BB (56.98%), BO (39.02%), OB (37.36%), and OO (39.24%). Blastocyst rates in FBF (42.8%) and control (45.0%) groups were superior (P < 0.05) to treatment OOO (26.0%) but similar (P > 0.05) to FOF, BBB, BOB, and OBO (32.0 to 35.8%). The average of blastocyst ICM cells of the group OOO (16.79) was inferior (P < 0.05) to the other groups. However, the average of TF cells on blastocysts of the group OOO (38.25) was similar (P > 0.05) to the groups BBB (45.74) and BOB (45.60) and inferior (P < 0.05) to the groups CONT (57.59), FBF (54.41), FOF (56.74), and OBO (47.35). The total average cells in the blastocysts of the group OOO (56.04) was inferior (P < 0.05) to the groups CONT (84.86), FBF (78.96), FOF (81.32), BBB (68.11), BOB (69.55), and OBO (69.82). The total cell number in the treatments, with several sources of protein supplementation, varied from 56.04 to 84.86. Considering the evaluation interval, this average cell number was discreetly inferior to that expected for the chronological age of the blastocysts. We concluded that it is possible to produce bovine embryos in the absence of F and/or B, with the protein source O, although it reduced blastocyst rates when used in all 3 steps of embryo in vitro production and resulted in blastocysts of inferior quality. Financial support: FAPESP 05/60389-2 and CNPq.


2006 ◽  
Vol 18 (2) ◽  
pp. 249 ◽  
Author(s):  
N. Maedomari ◽  
N. Kashiwazaki ◽  
M. Ozawa ◽  
A. Takizawa ◽  
J. Noguchi ◽  
...  

It is generally accepted that cumulus cells (CCs) support the nuclear maturation of immature oocytes in mammals. However, the precise mechanism of interaction between cumulus cells and oocytes has not been clarified. Furthermore, the role of cumulus cells in embryonic development has not been reported. In the present study, the effect of denuding cumulus cells from porcine oocytes on oocyte maturation, ertilization, and their subsequent development to the blastocyst stage was examined in vitro. In vitro maturation, fertilization, and culture were carried out as previously reported (Kikuchi et al. 2002 Biol. Reprod. 66, 1033-1041). Porcine cumulus-oocyte complexes (COCs) were collected; some of them were completely denuded of cumulus cells immediately after the collection (DO-0 group). The remaining intact COCs and the DO-0 oocytes were cultured for 24 h in the presence of dbcAMP and hormones. After the initial culture, some of the intact COCs were denuded either completely (DO-24 group) or partially (H-DO-24 group). Additionally, some of DO-24 oocytes were co-cultured with the cumulus cells removed at 0 h and pre-cultured for 24 h (DO-24 + CCs group). The denuded oocytes in each experimental group and intact COCs (control) were further cultured for total 46 h. The remaining oocytes with a first polar body were either examined for the levels of intracellular glutathione (GSH) or fertilized in vitro with frozen-thawed boar spermatozoa. The inseminated oocytes were cultured and examined for their fertilization status after 10 h and for their developmental competence after 6 days. Data were analyzed by ANOVA, followed by the Duncan's multiple range tests. The maturation rates of all denuded groups were significantly lower (P < 0.05; 34.3 to 45.0%) than that of the control group (64.5%). Intracellular GSH concentrations of all denuded groups were also significantly lower (P < 0.05; 4.03 to 7.00 pmol/oocyte) than that of the control group (9.60 pmol/oocyte); however, the GSH level of H-DO-24 oocytes was significantly higher (P < 0.05) than the GSH levels in the other denuded groups. Male pronuclear formation rates of completely denuded oocytes (DO-0, DO-24, and DO-24 + CCs groups) were significantly lower (P < 0.05; 41.4 to 59.3%) than those of the control (89.4%) and the H-DO-24 (80.0%) groups. The blastocyst rate of the control group was significantly higher (P < 0.05; 19.9%) than that of H-DO-24 group (11.6%), and these rates were significantly higher (P < 0.05) than those of the completely denuded groups (3.0 to 4.5%). The results suggest that the presence of cumulus cells during maturation culture improves nuclear maturation of oocytes and plays an important role in embryonic development to the blastocyst stage in vitro.


2012 ◽  
Vol 24 (1) ◽  
pp. 207 ◽  
Author(s):  
S. S. Kwak ◽  
S. A. Jeong ◽  
Y. B. Jeon ◽  
S. H. Hyun

The present study investigated the effects of resveratrol (a phytoalexin with various pharmacological activities) during in vitro maturation (IVM) of porcine oocytes on nuclear maturation, intracellular glutathione (GSH) and reactive oxygen species (ROS) levels, gene expression in matured oocytes and subsequent embryonic development after parthenogenetic activation (PA) and IVF. Data were analyzed with SPSS 17.0 using Duncan's multiple range test. In experiment 1, a total of 1146 cumulus–oocyte complexes (COC) were divided into 5 groups (0, 0.1, 0.5, 2.0 and 10.0 μM resveratrol). In the nuclear maturation after 44-h IVM, the groups of 0.1, 0.5 and 2.0 μM (83.0, 84.1 and 88.3%, respectively) had no significant difference compared to the control group (84.1%). The group of 10.0 μM decreased the nuclear maturation (75.0%) significantly (P < 0.05). In experiment 2, a total of 300 matured oocytes were examined for the effects of different resveratrol concentrations (0, 0.5, 2.0 and 10.0 μM) on porcine oocyte intracellular GSH and ROS levels. The groups of 0.5 and 2.0 μM showed a significant (P < 0.05) increase in intracellular GSH levels (1.3 and 1.3, respectively) compared with the control and 10.0 μM groups (1.0 and 1.0, respectively). The intracellular ROS level of oocytes matured with 2.0 μM resveratrol (0.4) was significantly (P < 0.05) decreased compared to other groups (control: 1.0; 0.5 μM: 0.6; and 10.0 μM: 0.7). In experiment 3, lower expression of apoptosis-related genes (Bax, Caspase-3 and Bak) was observed in matured oocytes treated with 2.0 μM resveratrol when compared with that of the control (P < 0.05). In experiment 4, a total of 728 oocytes were divided into 4 groups (control, 0.5, 2.0 and 10.0 μM) and examined subsequent to embryonic development after PA. Oocytes treated with 2.0 μM resveratrol during IVM had a significantly higher cleavage (CL) rate, blastocyst (BL) formation rate and total cell numbers (TCN) after PA compared with those of the control (2.0 μM: 96.6%, 62.1% and 49.1 vs control: 88.3%, 48.8% and 41.4, respectively) and the 10.0 μM groups (87.3%, 41.4% and 40.9, respectively). Oocytes treated with 0.5 μM resveratrol (87.2%, 50.5% and 48.6, respectively) during IVM had significantly higher TCN, but there were no differences in CL and BL formation rates. In experiment 5, a total of 935 oocytes in 3 groups (control, 2.0 and 10.0 μM resveratrol) were conducted in IVF. The BL formation rate and TCN were significantly higher in the group of 2.0 μM resveratrol (20.5% and 54.0, respectively) than the control (11.0% and 43.4, respectively) and 10.0 μM group (11.7% and 45.0, respectively), but there was no significant difference in CL rate. In conclusion, 2.0 μM resveratrol supplementation during IVM improved the developmental potential of PA and IVF in porcine embryos by increasing the intracellular GSH concentration, decreasing the ROS level and decreasing apoptosis-related gene expression during oocyte maturation. This work was supported by a grant from the Next-Generation BioGreen 21 Program (No. PJ008121), Rural Development Administration, Republic of Korea.


2016 ◽  
Vol 28 (2) ◽  
pp. 231
Author(s):  
P. C. Dall'Acqua ◽  
B. C. S. Leão ◽  
N. A. S. Rocha-Frigoni ◽  
M. Ambrogi ◽  
G. Z. Mingoti

Reactive oxygen species (ROS) are produced under normal culture conditions, but when production increases, it generates a harmful condition called oxidative stress (OS), leading to apoptosis and developmental blocks. Addition of antioxidants as melatonin to culture media has been used to minimize the effects of OS. Our hypothesis was that melatonin could improve oocyte in vitro maturation (IVM) and protect oocytes from ROS under a standard culture condition, thus increasing embryonic development. To test, cumulus-oocyte complexes were matured in TCM-199 with bicarbonate, 0.5 mg mL–1 of FSH, 100 IU mL–1 of hCG, and 10% FCS without supplementation (control group) or supplemented with 10–5 (MT5), 10–7 (MT7) or 10–9 (MT9) M melatonin for 22 h at 38.5°C and 5% CO2 in air. After IVM, a sample of oocytes (control, n = 59; MT5, n = 64; MT7, n = 77; MT9, n = 57) was stained with 1 µg mL–1 Hoechst 33342 to assess the nuclear maturation, and oocytes were classified as being in the stages of germinal vesicle (GV), germinal vesicle breakdown (GVBD), metaphase I (MI), anaphase I or telophase I (A/T), or metaphase II (MII). To determine the intracellular ROS levels, other matured oocytes (control, n = 46; MT5, n = 59; MT7, n = 51; MT9, n = 61) were stained with 5 µM CellROX®Green (Molecular Probes, Eugene, OR, USA) and were evaluated immediately under an epifluorescence inverted microscope (excitation 485 nm; emission 520 nm). The images were recorded and further analysed by Q-Capture Pro image software. After subtraction of the background signal intensity from the measured fluorescent signal intensity values, 1 group was chosen as a calibrator (control group), and each treatment value was divided by the mean calibrator value to generate the relative expression level (in arbitrary fluorescence units). Finally, another sample of matured oocytes (control, n = 188; MT5, n = 173; MT7, n = 180; MT9, n = 178) was submitted to IVF (Day = 0), and the presumptive zygotes were cultured in SOF at 38.5°C and 5% CO2 in air, for up to 7 days. The cleavage rates and embryonic development were evaluated at Days 3 and 7 of IVC, respectively. Data were analysed by ANOVA followed by Tukey’s test (P < 0.05) and are presented as mean ± SEM. There was no effect (P > 0.05) of different concentrations of MT on nuclear status of matured oocytes, as we found no differences in the rates of GV (0% to 5.3% ± 3.4), GVBD (5.4% ± 3.2 to 16.3% ± 5.0), MI (1.7% ± 1.7 to 3.2% ± 3.2), AI/TI (0% to 5.4% ± 3.4), and MII (74.8% ± 2.7 to 87.5% ± 3.7). The cleavage rates did not differ (P > 0.05) among treatments (76.7% ± 4.4 to 83.8% ± 2.7), as well as the embryonic development to the blastocyst stage (31.2% ± 1.9 to 43.7% ± 5.7). The intracellular ROS levels decreased significantly (P < 0.05) in the MT9 group (0.75 ± 0.03) in comparison to Control (1.0 ± 0.06), MT5 (0.97 ± 0.05) and MT7 (0.94 ± 0.05). In conclusion, supplementation with 10–9 M melatonin during IVM reduced the intracellular ROS levels of oocytes without interfering with the nuclear maturation and the subsequent embryonic development to the blastocyst stage. Financial support was provided by FAPESP (#2013/07382–6).


2021 ◽  
Vol 14 (1) ◽  
pp. 78-84
Author(s):  
Amro M. El-Sanea ◽  
Ahmed Sabry S. Abdoon ◽  
Omaima M. Kandil ◽  
Nahed E. El-Toukhy ◽  
Amal M. Abo El-maaty ◽  
...  

Aim: Oxidative stress (OS) is one of the major disruptors of oocyte developmental competence, which appears due to the imbalance between the production and neutralization of reactive oxygen species (ROS). Materials and Methods: In Experiment 1, buffalo oocytes were in vitro matured, fertilized, and cultured at 38.5°C under 5% CO2 + 20% O2 in standard CO2 incubator (OS) or under 5% O2 + 5% CO2 + 90% N2 (Multi-gas incubator, low O2). In Experiment 2, buffalo cumulus oocytes complexes (COCs) were matured in Basic maturation medium (BMM) composed of TCM199+ 10% FCS+ 10 μg/ml FSH+ 50 μg/ml gentamicin (control group) or in BMM supplemented with 50 μM ascorbic acid (ascorbic acid group) or 3.0 mM glutathione (glutathione group) or 10-5 M melatonin (melatonin group) and cultured at 38.5°C under 20% O2 for 24 h. Matured buffalo oocytes in control, ascorbic acid, or melatonin groups were fertilized and zygotes were cultured for 8 days under the same conditions. Results: In both experiments, maturation, cleavage, and blastocyst rates were recorded. Results showed that culture of buffalo oocytes under low O2 (5% O2) significantly increased maturation, cleavage, and blastocyst rates (p<0.05). Meanwhile, under 20% O2, addition of 10-5 M melatonin or 50 μM ascorbic acid to in vitro maturation (IVM) medium significantly improved cumulus cell expansion, nuclear maturation rates of buffalo oocytes (p<0.05), and increased cleavage and blastocyst rates (p<0.05). Conclusion: About 5% O2 is the optimum condition for in vitro production of buffalo embryos, and addition of 10-5 M melatonin to IVM medium for oocytes cultured under 20% O2 could alleviate the adverse effect of high oxygen tension and increased embryo yield.


2019 ◽  
Vol 25 (9) ◽  
pp. 538-549 ◽  
Author(s):  
Qing Guo ◽  
Mei-Fu Xuan ◽  
Zhao-Bo Luo ◽  
Jun-Xia Wang ◽  
Sheng-Zhong Han ◽  
...  

Abstract Baicalin, a traditional Chinese medicinal monomer whose chemical structure is known, can be used to treat female infertility. However, the effect of baicalin on embryonic development is unknown. This study investigated the effects of baicalin on in vitro development of parthenogenetically activated (PA) and in vitro fertilized (IVF) pig embryos and the underlying mechanisms involved. Treatment with 0.1 μg/ml baicalin significantly improved (P < 0.05) the in vitro developmental capacity of PA pig embryos by reducing the reactive oxygen species (ROS) levels and apoptosis and increasing the mitochondrial membrane potential (ΔΨm) and ATP level. mRNA and protein expression of sonic hedgehog (SHH) and GLI1, which are related to the SHH signaling pathway, in PA pig embryos at the 2-cell stage, were significantly higher in the baicalin-treated group than in the control group. To confirm that the SHH signaling pathway is involved in the mechanism by which baicalin improves embryonic development, we treated embryos with baicalin in the absence or presence of cyclopamine (Cy), an inhibitor of this pathway. Cy abolished the effects of baicalin on in vitro embryonic development. In conclusion, baicalin improves the in vitro developmental capacity of PA and IVF pig embryos by inhibiting ROS production and apoptosis, regulating mitochondrial activity and activating SHH signaling.


Sign in / Sign up

Export Citation Format

Share Document