scholarly journals 316EFFECTS OF ESTRADIOL-17² AND PROGESTERONE SUPPLEMENT ON THE RESUMPTION OF MEIOSIS OF CANINE OOCYTES MATURED IN VITRO

2004 ◽  
Vol 16 (2) ◽  
pp. 277
Author(s):  
M.K. Kim ◽  
Y.H. Fibrianto ◽  
H.J. Oh ◽  
G. Jang ◽  
K.S. Lee ◽  
...  

In the bitch, oocytes are ovulated at the germinal vesicle (GV) stage and mature in the isthmus of the oviduct around 3 days after ovulation, it is not known what elements trigger the release of this meiotic arrest. Canine IVM has shown limited success with maturation rates, usually around 20% (MII) (Farstad W, 2000 Anim. Reprod. Sci. 60–61, 375–387). Estrogen and progesterone are suggested to play a significant role in causing oocyte resumption of meiosis and progression to MII stage. The purpose of this study was to investigate the role of estradiol-17β (E2) and progesterone (P4) during in vitro maturation of canine oocytes in serum-free tissue culture medium (TCM)-199. Canine oocytes collected from bitches were categorized into three groups based on estrous stages, follicular, luteal, or anestrus, at routine ovariohystrectomy. Oocytes were cultured in vitro in TCM-199 supplemented with E2, P4 or E2+P4 according to experimental design at 39°C in 5% CO2 and O2. After 72h of maturation culture, oocytes were denuded, fixed in a 3.7% paraformaldehyde solution for 10min, stained with Hoechst 33342 in glycerol, and observed under the UV light. Three groups of oocytes were cultured in TCM-199 supplemented with different concentrations (0, 0.1, 1.0 or 2.0μgmL−1) of E2 (Experiment 1, n=898, replications: 5) or P4 (0, 0.5, 1.0 or 2.0μgmL−1, Experiment 2, n=734, replications: 5). Multiple comparisons were implemented using Generalized Linear Models in the SAS 8.12 program. The rates of oocyte maturation to MII stage were higher (P<0.05) in follicular stage oocytes cultured with 2μgmL−1 E2 (17.9%) compared to other supplement groups (0 to 7.6%). No differences (P<0.05) in rate of MII stage oocytes among P4 supplement groups were observed. In Experiment 3, to investigate the combined effects of E2 and P4 on in vitro maturation, three groups of oocytes were cultured in TCM-199 supplemented with 2μgmL−1 E2 and various concentration of P4 (0, 0.5, 1.0 or 2.0μgmL−1, Experiment 3, n=1613, replications: 5). The rate of oocyte maturation to MII stage (11.5%) was higher (P<0.05) in follicular stage oocytes cultured with 2μgmL−1 E2+2.0μgmL−1 P4 supplement compared to other supplement groups (0 to 6.4%). In conclusion, the present study demonstrated that E2 supplement in the culture medium increased maturation of canine oocyte to MII stage and that supplement of P4 alone did not promote oocyte maturation. However, P4 supplemented with E2 further promoted oocyte maturation in the follicular stage compared to E2 supplement alone, indicating that P4 acts synergistically with E2 on canine oocyte maturation in the presence of E2. From our results, we conclude that canine oocytes are exposed to high levels of P4 during maturation due to the preovulatory luteinization of canine follicles which gives rise to high intrafollicular as well as intratubal P4 concentrations-this is very different from the situation in oocytes from other domestic animal species. This study was supported by Biogreen 21-1000520030100000.

1998 ◽  
Vol 13 (6) ◽  
pp. 1638-1644 ◽  
Author(s):  
P. T. Goud ◽  
A. P. Goud ◽  
C. Qian ◽  
H. Laverge ◽  
J. Van der Elst ◽  
...  

2009 ◽  
Vol 21 (1) ◽  
pp. 225
Author(s):  
S. E. Racedo ◽  
V. Y. Rawe ◽  
H. Niemann

The process of maturation encompasses a complex series of molecular and structural events. Completion of the nuclear changes to produce a metaphase II (MII) oocyte does not reflect the molecular and structural maturity of an oocyte, which is sometimes termed cytoplasmic maturation. The Golgi apparatus phosphorylates, fragments, and changes the localization during oocyte maturation. GM130 and phospho-GM130 are used as markers for the Golgi apparatus and phosphorylated Golgi apparatus, respectively. The goal of this study was to analyze the dynamics of the Golgi apparatus and its association with microtubules in bovine oocytes at different stages of in vitro maturation [IVM; i.e. germinal vesicle (GV), germinal vesicle breakdown (GVBD), metaphase I (MI), and MII]. The roles of CDC2A kinase (also known as p34cdc2) and cytoplasmic-dynein ATPase on Golgi dynamics were studied by using specific inhibitors. The distribution of the markers was assessed by immunocytochemistry and laser confocal microscopy. To unravel the role of CDC2A and cytoplasmic dynein ATPase on the dynamics of the Golgi apparatus, the inhibitors roscovitine (ROS) and sodium-orthovanadate (SOV), respectively, were used. In the first experiment, the nuclear maturation rate was checked in the presence of the inhibitors at different times and for different incubation times to explore whether oocytes were able to reach the MII stage. At the GV and GVBD stages, the Golgi apparatus is observed as fragments named mini-Golgies and at the MI and MII stages as punctate foci throughout the cytoplasm. Our results showed 2 well-defined movements of the Golgi apparatus toward opposite directions, depending on the maturation stage. The first movement was observed between 5 and 9 h of IVM (i.e. the GVBD stage), when the Golgi apparatus relocalized from the ooplasm to the periphery. The second movement was observed between 9 and 15 h of IVM (i.e. the MI stage), when the Golgi apparatus moved from the cortex to throughout the cytoplasm and remained there up to the MII stage. The use of inhibitors on CDC2A and cytoplasmic-dynein ATPase at selected time points revealed that CDC2A played a crucial role on the distribution of this organelle during the first movement, whereas the final localization at the GVBD stage was dependent on cytoplasmic-dynein transport. The second movement of the Golgi apparatus was disturbed by the SOV treatment, but not by the use of ROS, suggesting a role of cytoplasmic-dynein-dependent transport during the distribution and organization of the punctate foci at the MI stage. The phosphorylation status of Golgi was not affected at the different incubation times with inhibitors, except in those oocytes incubated with ROS for 24 h, suggesting a role of CDC2A. In conclusion, we describe the involvement of CDC2A during the first movement of the Golgi apparatus and the importance of cytoplasmic-dynein ATPase activity in the first and second relocalization of Golgi during bovine oocyte maturation. DAAD.


1992 ◽  
Vol 12 (7) ◽  
pp. 3192-3203 ◽  
Author(s):  
K M Pickham ◽  
A N Meyer ◽  
J Li ◽  
D J Donoghue

The p34cdc2 protein kinase is a component of maturation-promoting factor, the master regulator of the cell cycle in all eukaryotes. The activity of p34cdc2 is itself tightly regulated by phosphorylation and dephosphorylation. Predicted regulatory phosphorylation sites of Xenopus p34cdc2 were mutated in vitro, and in vitro-transcribed RNAs were injected into Xenopus oocytes. The cdc2 single mutants Thr-14----Ala and Tyr-15----Phe did not induce germinal vesicle breakdown (BVBD) upon microinjection into oocytes. In contrast, the cdc2 double mutant Ala-14/Phe-15 did induce GVBD. Both the Ala-14 and Ala-14/Phe-15p34cdc2 mutants were shown to coimmunoprecipitate cyclin B1 and to phosphorylate histone H1 in immune complex kinase assays. Microinjection of antisense oligonucleotides to c-mosXe was used to demonstrate the role of mos protein synthesis in the induction of GVBD by the Ala-14/Phe-15 cdc2 mutant. Thr-161 was also mutated. p34cdc2 single mutants Ala-161 and Glu-161 and triple mutants Ala-14/Phe-15/Ala-161 and Ala-14/Phe-15/Glu-161 failed to induce GVBD in oocytes and showed a decreased binding to cyclin B1 in coimmunoprecipitations. Each of the cdc2 mutants was also assayed by coinjection with cyclin B1 or c-mosXe RNA into oocytes. Several of the cdc2 mutants were found to affect the kinetics of cyclin B1 and/or mos-induced GVBD upon coinjection, although none affected the rate of progesterone-induced maturation. We demonstrate here the significance of Thr-14, Tyr-15, and Thr-161 of p34cdc2 in Xenopus oocyte maturation. In addition, these results suggest a regulatory role for mosXe in induction of oocyte maturation by the cdc2 mutant Ala-14/Phe-15.


2015 ◽  
Vol 27 (1) ◽  
pp. 245
Author(s):  
A. Sato ◽  
B. Sarentonglaga ◽  
K. Ogata ◽  
M. Yamaguchi ◽  
A. Hara ◽  
...  

Although in vitro maturation (IVM) of oocytes has been successfully established for many species, the efficiency of IVM in canine oocytes is still very low. As growth factors have been shown to promote oocyte maturation in some species, we investigated whether use of transforming growth factor α (TGF-a) and insulin-like growth factor 1 (IGF-1) might overcome the difficulties of achieving meiotic maturation in cultured canine cumulus-oocyte complexes (COC). Ovaries were obtained from bitches at 6 months to 7 years of age by ovariohysterectomy and were sliced repeatedly to release COC. In the first experiment, the COC were cultured at 38.8°C for 48 h in 5% CO2 in air in medium 199 supplemented with either TGF-a (0, 1, 10, or 100 ng mL–1) or IGF-1 (0, 0.5, 5, 10, or 50 µg mL–1). In the second experiment, the synergistic effect of TGF-a and IGF-1 was investigated by culturing COC in medium 199 supplemented with both TGF-a (0, 1, 10, or 100 ng mL–1) and IGF-1 (0, 0.5, 5, 10, or 50 µg mL–1). At the end of the culture period, the oocytes were denuded of cumulus cells by pipetting with a fine bore glass pipette; the denuded oocytes were then fixed in Carnoy's solution and stained with Hoechst 33342. The nuclear configuration and chromatin morphology of the oocytes were evaluated under confocal laser scanning microscopy. The cells were assigned to 1 of the following meiotic stages: germinal vesicle (GV), germinal vesicle breakdown (GVBD), metaphase I (MI), or metaphase II (MII). Data were analysed by ANOVA with Fisher's PLSD test. In experiment 1, no significant difference were observed in the rates of cells maturing to the MI and MII stages, but that in the 10 ng mL–1 of TGF-a group (56.3%) were larger than in the other treatment groups (38.8–51.0%). The frequencies of MII stage cells in the 5, 10, and 50 µg mL–1 of IGF-1 treatment groups (9.8, 13.3, and 12.2%, respectively) were significantly higher than in the 0.5 µg mL–1 of IGF-1 group and the control group (5.3 and 2.2%, respectively). In experiment 2, the frequency of MI and MII cells in the control, 1 ng mL–1 of TGF-a plus 0.5 µg mL–1 of IGF-1, 10 ng mL–1 of TGF-a plus 5 µg mL–1 of IGF-1, 10 ng mL–1 of TGF-a plus 10 µg mL–1 of IGF-1, and 100 ng mL–1 of TGF-a plus 50 µg mL–1 of IGF-1 group were 44.1, 36.1, 63.5, 70.8, and 50.8%, respectively. The frequency of MII cells in the control group and the same treatment groups were 2.8, 7.2, 10.4, 15.3, and 10.8%, respectively. Both frequencies in the 10 ng mL–1 of TGF-a plus 10 µg mL–1 of IGF-1 group were significantly higher than in the control group. The TGF-a may act in a paracrine fashion on the surrounding granulosa cells, and IGF-1 may play multiple roles in cellular metabolism, proliferation, growth, and differentiation in canine oocyte maturation, as has been reported for many other species. In conclusion, these results demonstrate that a synergistic effect between TGF-a and IGF-1 produces an increased rate of in vitro maturation to the MI and MII stages in canine oocytes.


Author(s):  
Li Meng ◽  
Jean Rutledge ◽  
Ying Zhu ◽  
Gerald M. Kidder ◽  
Firouz Khamsi ◽  
...  

2006 ◽  
Vol 18 (2) ◽  
pp. 230
Author(s):  
X.-S. Cui ◽  
X.-Y. Li ◽  
N.-H. Kim

Cell division cycle 42 (Cdc42), a member of the Rho family of small guanosine triphosphatase (GTPase) proteins, regulates multiple cell functions, including motility, proliferation, apoptosis, and cell morphology. In order to gain insight into the role of Cdc42 in embryo development, we first characterized mRNA and protein levels of Cdc42 in mouse oocytes and early embryogenesis. We then examined the possible role of the gene in oocyte maturation and pre-implantation development using RNA interference analysis. The relative abundance of Cdc42 transcripts were measured by real time RT-PCR. After normalization with histone H2a mRNA levels, the mRNA expression of Cdc42 was abundant in immature oocytes and reduced slightly in zygotes and 2- to 8-cell stage embryos. The expression levels were significantly increased during the morula and blastocyst stages. Indirect immunocytochemistry showed protein synthesis of Cdc42 in oocytes and embryos of all stages. Introducing small interference RNA (siRNA) of Cdc42 into germinal vesicle stage oocytes or zygotes specifically reduce both mRNA expression and protein synthesis of Cdc42 in metaphase II stage oocytes and early embryos developing in vitro. Meiotic maturation was significantly reduced following siRNA injection into germinal vesicle stage oocytes. It is evident that actin distribution in siRNA treated blastocysts is morphologically abnormal following injection of siRNA for Cdc42. Injection of siRNA into zygotes did not influence cleavage, but significantly decreased in vitro development to morulae and blastocysts. While housekeeping genes such as tissue plasminogen activator were not altered by siRNA, wiskott-aldrich syndrome protein family 1 (WASP1) mRNA was down-regulated in the morula. Interestingly, mRNA of WASP1, tubulin alpha 1 (Tuba1), and actin-related protein 2/3 complex subunit V (Arpc5) increased at the blastocyst stage following siRNA injection. These results suggest that Cdc42 plays an important role during oocyte maturation and early pre-implantation development, likely through linkage with several other genes. This work was funded by a grant from National Research Laboratory Program in Korea.


Author(s):  
L.S.S. Varaprasad Reddy ◽  
B.R. Naik ◽  
A.V.N. Sivakumar ◽  
B. Punyakumari ◽  
J. Suresh

Background: Ovarian follicular development and growth are controlled by many hormones and growth factors. Despite the fact that LH and estradiol-17β have been utilized for the in vitro culture of preantral follicles yet, the suitable time points of supplementation of LH and estradiol-17β is not known. Therefore this study aimed to investigate the influence of addition of LH and estradiol-17β at different time points on in vitro development of preantral follicles (PFs’) in sheep. Method: Preantral follicles isolated from the ovarian cortical slices using micro dissection method were cultured for six days in Bicarbonate buffered Tissue culture medium 199B (TCM 199B) or in a standard culture medium supplemented with LH (2 μg/ml) and estradiol-17β (5 ng/ml) at different points during the culture period. COCs isolated from the follicles at the end of six day culture in different treatments were subjected to in vitro maturation for additional 24h. Result: Supplementation of LH and estradiol-17β during last two days of the culture supported better proportion of PFs’ exhibiting growth whereas supplementation of LH and estradiol-17β during first two days of the culture supported better average increase in diameter and proportion of PFs’ exhibiting antrum formation at the end of six day culture. Further the oocytes in COCs isolated at the end of culture in these treatments and subsequently subjected to in vitro maturation (IVM) for 24hr developed at a higher frequency to MII (metaphase II) stage. Supplementation of LH and estradiol-17β to TCM 199B culture medium in early stages followed by standard medium alone in later stages supports better development of PFs’ in vitro. Following supplementation with LH and estradiol-17β for the first two days culture of PFs’ in standard medium appears to be advantageous for the development of preantral follicles in vitro.


Reproduction ◽  
2003 ◽  
pp. 509-515 ◽  
Author(s):  
A Martoriati ◽  
M Caillaud ◽  
G Goudet ◽  
N Gerard

Interleukin 1 beta (IL-1 beta) inhibits the LH-induced resumption of meiosis of equine oocytes in vitro. The present study was performed to clarify this inhibitory effect of IL-1 beta by testing increasing concentrations of IL-1 beta, and by measuring the effect of addition of IL-1 receptor antagonist (IL-1RA) to the culture medium. The effect of IL-1 beta on epidermal growth factor (EGF)-induced resumption of meiosis was also studied. Cumulus-oocyte complexes (COCs) were collected from subordinate follicles on ovaries obtained from an abattoir. In five distinct experiments, COCs were cultured for 30 h and nuclear maturation of oocytes was evaluated by DNA staining. In Expt 1, seven different media were tested: medium 1 (TCM199+BSA); medium 2 (medium 1+50 ng IL-1 beta ml(-1)); medium 3 (medium 1+eLH); and media 4, 5, 6 and 7 (medium 3 containing 0.1, 1.0, 10.0 and 50.0 ng IL-1 beta ml(-1), respectively). In Expt 2, four different media were tested: medium 1 (TCM199+BSA+eLH); medium 2 (medium 1+50 ng IL-1 beta ml(-1)); and media 3 and 4 (medium 2+IL-1RA at 50 and 100 ng ml(-1), respectively). In Expt 3, three different media were tested: medium 1 (TCM199+BSA+eLH); medium 2 (medium 1+50 ng IL-1RA ml(-1)); and medium 3 (medium 2+50 ng IL-1 beta ml(-1)). In Expt 4, four different media were tested: medium 1 (TCM199+BSA+eLH); and media 2, 3 and 4 (medium 1+IL-1RA at 50, 100 and 150 ng ml(-1), respectively). In Expt 5, three different media were tested: medium 1 (TCM199+BSA+EGF); medium 2 (medium 1+50 ng IL-1 beta ml(-1)); and medium 3 (medium 2+50 ng IL-1RA ml(-1)). In Expt 1, LH alone induced an increase in the rate of in vitro maturation (IVM) of equine oocytes (P<0.05), whereas IL-1 beta alone did not have any effect compared with medium 1. IL-1 beta (50 ng ml(-1)) significantly inhibited the eLH-induced IVM of oocytes (P<0.05) compared with medium 3. A decrease in rate of maturation was observed from a concentration of 10 ng IL-1 beta ml(-1) onwards. In Expt 2, the presence of IL-1RA in the culture medium inhibited the effect of IL-1 beta and restored the rate of oocyte maturation (P<0.05) observed in the presence of LH alone. In Expts 3 and 4 it was demonstrated that IL-1RA alone had no positive effect on the eLH-induced rate of maturation. In Expt 5, IL-1 beta inhibited the EGF-induced resumption of meiosis (P<0.05). The addition of IL-1RA inhibited this effect and restored the rate of oocyte maturation (P<0.05) observed with EGF alone. In conclusion, the present data confirm the inhibitory effect of IL-1 beta on IVM of equine oocytes induced by eLH and demonstrate its inhibitory effect on EGF-induced oocyte maturation. The rate of maturation decreased in a dose-dependent way and the lowest rate of maturation was observed at 50 ng IL-1 beta ml(-1) (P<0.05). The use of IL-1RA inhibited these effects, demonstrating that the action of IL-1 beta is receptor-mediated. Moreover, the results clearly show that, in equine species, IL-1 beta is involved in the physiology of COCs by regulating resumption of meiosis.


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