• Journal of Embryo Transfer
• /
• v.22 no.1
• /
• pp.1-7
• /
• 2007

This study was conducted to examine the role of intact cumulus cells during in vitro fertilization (IVF) on sperm penetration, male pronuclear (MPN) formation and subsequent embryo development of oocytes matured and fertilized in vitro. Cumulus-oocyte complexes obtained from the slaughtered gilt ovaries were matured for 44 h in TCM199 containing 10% porcine follicular fluid, epidermal growth factor and hormones. After maturation culture, denuded oocytes or oocytes with intact cumulus cells were coincubated with frozen-thawed boar semen for 8h in a modified tris-buffered medium containing 5mM caffeine and 10mM calcium chloride. Putative zygotes were fixed and examined for sperm penetration and MPN formation (Experiments $1{\sim}3$), or cultured in North Carolina State University-23 medium fo. 156 h (Experiment 3). In Experiment 1, sperm penetration was examined after insemination of denuded oocytes and oocytes with intact cumulus cells at the concentration of $7.5{\times}10^5$ sperm/ml. Optimal sperm concentration for IVF of cumulus-intact oocytes was determined in Experiment 2 by inseminating intact oocytes with $2{\sim}5{\times}10^6$ sperm/ml. In Experiment 3, denuded or intact oocytes were inseminated at the concentrations of $7.5{\times}10^5$ and $4.0{\times}10^6$ sperm/ml, respectively, and in vitro embryo development was compared. Sperm penetration was significantly (p<0.01) decreased in cumulus-intact oocytes compared to denuded oocytes (35.2% vs. 77.4%). Based on the rates of sperm penetration and normal fertilization, the concentration of $4.0{\times}10^6$ sperm/ml was optimal for the IVF of intact oocytes compared to other sperm concentrations. The presence of intact cumulus cells during IVF significantly (p<0.05) improved embryo cleavage (48.8% vs. 58.9%), blastocyst (BL) formation (11.0% vs. 22.8%) and embryo cell number $(22{\pm}2\;vs.\;29{\pm}2\;cells)$ compared to denuded oocytes. In conclusion, these results suggest that intact cumulus cells during IVF inhibit sperm penetration but improve embryo cleavage, BL formation and embryo cell number of porcine embryos produced in vitro.

• Clinical and Experimental Reproductive Medicine
• /
• v.34 no.2
• /
• pp.95-106
• /
• 2007

Objective: We previously identified differentially expressed genes (DEGs) between germinal vesicle (GV) and metaphase II (MII) mouse oocyte. The present study was accomplished as a preliminary study to elucidate the role of ribose 5-phosphate isomerase A (Rpia), the essential enzyme of the pentose phosphate pathway (PPP), in oocyte maturation. We observed expression of Rpia in the mouse and porcine oocytes. Methods: Expression pattern of the 11 MII-selective DEGs in various tissues was evaluated using RT-PCR and selected 4 genes highly expressed in the ovary. According to the oocyte-selective expression profile, we selected Rpia as a target for this study. We identified the porcine Rpia sequence using EST clustering technique, since it is not yet registered in public databases. Results: The extended porcine Rpia nucleotide sequence was submitted and registered to GenBank (accession number EF213106). We prepared primers for porcine Rpia according to this sequence. In contrast to the oocyte-specific expression in the mouse, Rpia was expressed in porcine cumulus and granulosa cells as well as in oocytes. Conclusion: This is the first report on the characterization of the Rpia gene in the mouse and porcine ovarian cells. Results of the present study suggest that the mouse and porcine COCs employ different mechanism of glucose metabolism. Therefore, the different metabolic pathways during in vitro oocyte maturation (IVM) in different species may lead different maturation rates. It is required to study further regarding the role of Rpia in glucose metabolism of oocytes and follicular cell fore exploring the regulatory mechanism of oocyte maturation as well as for finding the finest culture conditions for in vitro maturation.

• Korean Journal of Animal Reproduction
• /
• v.22 no.2
• /
• pp.187-194
• /
• 1998

In order to determine suitable conditions for rapid freezing of porcine embryos, the kind and concentration of cryoprotectants, sucrose concentrations, equilibration time and thawing temperature in freezing medium were examined in relation to the survival of frozen-thawed oocyte and embryos. The results obtained are as follows : 1. The suitable concentrations of cryoprotoctant in the freezing medium which consisted of TCM-199+20% FCS were 1.5M for glycerol, 2.0M for DMSO, 2.5M for ethylene glycol, and 2.0M for propanediol. The sucrose concentration of 0.25M in the medium was found to optimal because the survival rate was markedly higher at this concentration when compared to the others. The survival rate was relatively high when the frozen embryos were thawed at 30$^{\circ}C$ in the freezing medium containing 2.5M cryoprotectants. The equilibration periods of 2.0 and 5.0 minutes revealed the higher survival in the media containing 1.5 or 2.1M glycerol when compared to 10 and 15 minutes. 2. The fertilization rates of frozen-thawed follicular oocytes which matured in vitro for 1, 12, 24 and 48 hours were 6.7~26.7% depending on the maturation time, and the rates were relatively high for those matured for a short period of time. The survival rates of frozen-thawed oocytes which matured in vitro for certain periods and fertilized were 10.0~30.0% depending on the maturation time.

• Journal of Embryo Transfer
• /
• v.16 no.3
• /
• pp.203-211
• /
• 2001

This study was carried out to determine sex of porcine embryos produced by in vitro fertilization. Porcine oocyte-cumulus complexes were cultured in BSA-free North Carolina State University (NCSU) 23 medium containing porcine follicular fluid (10%), cystein (0.1 mg/ml) and hormonal supplement (10 IU eCG and 10 IU hCG per ml) for 20~22 hrs. They were then cultured in the same medium but without hormonal supplement for additional 20~22 hrs. After culture, cumulus cells were removed and oocytes were co-incubated for 6 hrs with four different concentrations (5$\times$10$^4$, 2.5$\times$ 10$^{5}$ , 5.0$\times$10$^{5}$ and l0$\times$10$^{5}$ ) of porcine sperm. After fertilization, oocytes were transferred into NCSU 23 with 0.4% BSA medium. The cleavage and blastocyst formation rates were evaluated at 48 and 144 hrs, respectively. In this study, the polymerase chain reaction (PCR) was used to determine the sex of porcine embryos in the stage of blastocyst. The PCR was performed using a set of oligonucleotide primers (5‘-TCATGGACCAGGTAGGGAAT-3', 5’-GAAAGACACGTCCTTGGA GA-3') for 491 bp fragment of porcine male-specific DNA sequence. In the flour different sperm concentration (5$\times$10$^4$, 2.5$\times$10$^{5}$ , 5.0$\times$10$^{5}$ and l0$\times$10$^{5}$ ) for fertilization condition, the cleavage rate was 55.95, 67.88, 60.18 and 47.60%, respectivety, and the development rate of blastocysts was 16.03, 20.40, 21.41 and 12.37%, respectively. At 5.0$\times$10$^4$and 2.5$\times$10$^{5}$ of sperm concentrations per ml cleavage rate and development rate of blastocyst were higher than those of 5.0$\times$10$^4$and l0$\times$10$^{5}$ of sperm concentration (P<0.01). The male of porcine embryos was detected at 491 bp by PCR, and 18 of the 31 porcine blastocysts were the male (58.1%) and the rest 13 were the female(41.9%).

• Journal of Embryo Transfer
• /
• v.10 no.2
• /
• pp.139-144
• /
• 1995

10% ethanol에 의한 처녀발생유가 및 체외수정된 돼지 난포란을 CZB와 CRlaa 에서 배양하여 배발달율을 조사하였다. 또한 CZB에 각기 다른 농도의 cholesterol (0$\mu$g/mL, 2$\mu$g/mL, 5$\mu$g/mL, 10$\mu$g/mL)을 첨가한 후 체외수정된 돼지 난포란을 배양하여 배발달률을 조사하였다. CZB 구는 BOEC와 공배양하였다. 처녀발생유가 48시간 후 2~8세포기로 발달한 난자의 비율은 CZB 구가 32.2%, CRlaa구가 16.8%였으며, 192시간후 상실배로 발달한 난자의 비율은 CZB구가 5.75%, CRlaa구가 0%였다. 체외수정 48시간 후 2~8세포기로 발달한 난자의 비율은 CZB 구가 42.4%, 81%, CRlaa 구가 17.6%였으며, 192시간 후 상실배로 발달한 난자의 비율은 CZB 구가 5.81%, CRlaa 구가 0%였다. 각기 다른 농도의 cholesterol이 첨가된 CZB구에서 상실배로 발달한 난자의 비율은 각각 0,10,0.45,0%였다.

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2002.11a
• /
• pp.117-117
• /
• 2002

The oocytes from most of animal species accumulate genetic information and other necessary materials during oogenesis for the later use in the early development. Over the years oocyte maturation has been studied extensively both in vitro and in vivo. Particularly, maturation of follicular oocyte in vitro becomes one of the important tools for the studies of basic cell biology, the in vitro technology of animal production, and in particular, the somatic cell cloning by nuclear transfer. We examined meiotic maturation and cumulus expansion in the presence of translation or transcription inhibitors for varying periods of in viかo maturation (IVM) of pig oocyte. In Experiment 1, the results revealed that translation and transcription inhibitors inhibited cumulus expansion and meiotic maturation during 35h of IVM. However, 50 to 60% of the oocytes underwent nuclear maturation without cumulus expansion during 75h of IVM. The rest of the oocytes were arrested at metaphase I (40-50%) in the presence of the inhibitors. In Experiment II, the OCCs were exposed to the drugs only for 15h to examine translation and transcription inhibitors on cumulus expansion and meiotic maturation. Transcription inhibitors for 15h did not arrest meiotic maturation when the oocytes were cultured for subsequent, necessary period of IVM, whereas cumulus expansion was completely inhibited, suggesting that initial 15h is critical transcription activity far cumulus expansion. Translation inhibitors for 15h exposure did not alter cumulus expansion and meiotic maturation during subsequent culture in the absence of the drugs. In Experiment III, the OCCs were exposed to the drugs only for later 30h to examine the influence of transcription and translation inhibitors on oocyte maturation. Interestingly, all meiotic maturation underwent normally with full expansion of cumulus. Similar results were obtained from Experiment IV where 5h of exposure from 15 to 20h of IVM culture to the drugs was performed and subsequently cultured for same period in fresh medium. Taken there results together, both transcription and translation are necessary for nuclear maturation and cumulus expansion, and first 15h IVM for cumulus expansion is critical. The arrested oocytes by the drugs were still capable of undergoing nuclear maturation, although cumulus expansion was affected.

• Proceedings of the KSAR Conference
• /
• 2003.06a
• /
• pp.33-33
• /
• 2003

This study was conduct to compare the efficacy to produce male and female somatic cloned piglets. Maturation of porcine COCs was accomplished by incubation in NCSU-23 medium supplemented with 0.6 mM cysteine, 10% porcine follicular fluid, 1mM dibutyryl cyclic adenosine monophosphate (dbc-AMP, Sigma, USA), and 0.1 IU/ml human menopausal gonadotrophin (hMG, Teikokuzoki, Japan) for 20h and then cultured without dbcAMP and hMG for another 18 to 24 h. Female and male fetal cells were isolated from each fetus, cultured in ES-DMEM medium containing 10% FCS. Enucleated oocytes were fused with fetal fibroblasts (passage 4 to 15). Reconstructed embryos were cultured in NCSU-23 with 4 mg/ml BSA under mineral oil at 39$^{\circ}C$ in 5% $CO_2$ in air. A total of 12,328 nuclear-transferred embryos (1- to 4-cell stage) were surgically transferred into 69 surrogate gilts. Three recipients aborted during the period of conception. Three gilts delivered eleven female piglets, and five recipients gave rise to birth 22 male piglets. The average birth weigh of the cloned piglets was 1.52 kg (1.38~1.83 kg) in female piglets and 0.84 kg (0.45~1.25 kg) in male piglets. Alive cloned pigs was seven in female piglets (63.6%) and four in male piglets (18.2%). The other two recipients is ongoing. This study suggests that female-derived fetal cell as a nuclear donor has more capability on production of cloned piglets than male.

• Korean Journal of Animal Reproduction
• /
• v.27 no.1
• /
• pp.77-85
• /
• 2003

This study was undertaken to evaluate the effects of catalase using xanthine (X)-xanthine oxidase (XO) system on in vitro maturation and fertilization in the pig. When follicular oocytes were cultured with X or XO, the maturation rates were not significantly different between in medium with and without catalase despite of different culture periods. However, significantly (P<0.05) higher maturation rates were obtained in culture with X-XO-catalase system. The rates of degenerated oocytes were increased with culture periods prolonged, and were significantly (P<0.05) higher in medium without that than with catalase at 120 h of culture. On the other hand, the parthenogenetic oocytes were observed with high proportions at 72 h of culture, but were not different between the medium with and without catalase at various times of culture. In another experiment, the frozen-thawed boar spermatozoa treated with X-XO system for in vitro fertilization. The penetration rates were higher in medium with that than without catalase during the in vitro fertilization with none (P<0.05), XO and X+XO. On the other hand, when sperm were treated with none, X, XO and X+XO, lipid peroxidation were produced with higher rates in medium without that than with catalase, and consequently the changes in sperm penetration and lipid peroxidation showed opposite patterns. Under the above all conditions, however, sperm-SH group were higher detected by catalase. When the activity of sperm binding to zona pellucida was evaluated through binding to salt-stored porcine oocytes, sperm binding to zona pellucida in control group were higher than in medium with X, XO and X+XO groups. No significant differences, however, were observed between medium with and without catalase. In conclusion, the exposure of follicular oocytes and spermatozoa to X-XO-catalase system may be caused stimulating in vitro maturation and fertilization in the pig.

• Current Research on Agriculture and Life Sciences
• /
• v.8
• /
• pp.45-50
• /
• 1990

This study was carried out ot investigate the effects of fetal calf serum (FCS) and gonadotropins supplemented to the medium on maturation and fertilization in vitro of porcine follcular oocytes. Ovaries were obtained from gilts at local slaughter-house. Oocyte-cumulus complexes were recovered by puncturing the ovarian follicles(3~5 mm in diameter). The complexes from individual ovaries were pooled in a $0.4m{\ell}$ droplet of medium covered with paraffin oil, then washed twice in fresh droplet and cultured for 36hrs in culture media according to experimental conditions. Boar epididymal spermatozoa were capacitated by preincubation for 4hrs in m-KRB medium and the preincubated spermatozoa were insemenated in the fertilization medium containing the cultured oocytes. The results obtained in this study are summarized as follows: 1. The maturation rates of oocytes cultured in m-KRB and m-KRB supplemented to 10% FCS were 82 and 37%, respectively. When PMSG, hCG. and PMSGt hcG($10Iu/m{\ell}$) were added to the media supplemented to 10% FCS, the maturation rates were 66, 58 and 68%, respectively. 2. Expansion of cumulus cells was not occured in m-KRB and m-KRB supplemented to 10% FCS. However, when PMSG, hCG and PMSG+hCG($10Iu/m{\ell}$) were added to m-KRB supplemented to 10% FCS, the expansion rates of cumulus cell layers were 92, 13 and 91%, respectively. 3. When oocytes were mltured in m-KRB, the rates of penetration and formation of male pronucle: were 93 and 7%, respectively. By adding FCS and gonadotropin to m-KRB, the penetration and formation of male pronuclei were 100 80%, respectively.

• Journal of Embryo Transfer
• /
• v.25 no.1
• /
• pp.1-7
• /
• 2010

The objective of this study was to examine the effect of vitamin B (pantothenic acid, folic acid, and myo-inositol) that was supplemented to embryo culture medium on in vitro development of parthenogenetically activated (PA) pig embryos. Cumulus-oocyte complexes derived from slaughtered ovaries were matured in TCM-199 supplemented with porcine follicular fluid, cysteine, pyruvate, EGF, insulin, and hormones (hCG and eCG) for the first 22 h and then further cultured in hormone-free medium for an additional 22 h. After maturation culture, metaphase II oocytes that extruded 1st polar body were electrically activated and treated with $5.0\;{\mu}g/ml$ cytochalasin B for 4 h. Then, PA embryos were cultured for 7 days in a modified NCSU-23 that was supplemented with pantothenic acid, myo-inositol, or folic acid at different concentrations ($3{\sim}300\;{\mu}M$) according to the experimental design. Myo-inositol added to culture medium did not show any beneficial or inhibitory effects on embryo cleavage and blastocyst formation. However, $300\;{\mu}M$ pantothenic acid significantly inhibited blastocyst formation compared to control (no addition) (24% vs. 36%, p<0.05). Folic acid ($300\;{\mu}M$) significantly (p<0.05) increased blastocyst formation (56%) compared to control (41%). Our results demonstrated that in vitro development of PA embryos was significantly influenced by vitamin B and addition of $300\;{\mu}M$ folic acid to culture medium improved in vitro development of pig PA embryos.