• 한국가축번식학회지
• /
• 제21권3호
• /
• pp.293-302
• /
• 1997

Follicular oocytes of Grade I and II were collected from 2~6 mm ovarian follicles and matured in vitro (IVM) for 24 hrs in TCM-199 su, pp.emented with 35$\mu\textrm{g}$/ml FSH, 10$\mu\textrm{g}$/ml LH, and 1$\mu\textrm{g}$/ml estradiol-17$\beta$ at 39$^{\circ}C$ under 5% CO2 in air. They were fretilized in vitro (IVF) by epididymal spermatozoa capacitated with heparin for 12 hrs. The zygotes were then co-cultured in vitro with bovine oviducted epithelial cells (BOEC) for 7 to 9 days. The optimal time for IVM, the successful enucleation of IVM oocytes by micromanipulation at different oocyte ages after IVM, and the ideal culture system for IVM for effective IVF and in vitro development of IVM-IVF embryos was examined for in vitro production of nuclear recipient oocytes and nuclear donor embryos. To improve the efficiency of nuclear transplantation (NT) of IVF embryo into IVM follicular oocytes, this study evaluated the optimal electric condition and oocytes age for activation of IVM oocytes and in vitro development of NT embryos. In vitro development of NT embryos with preactivation or non-preactivation in enucleation oocytes, cell number of IVN-IVF embryos, and NT embryos wre also examined. The results obtained were as follows; 1. The most suitable enucleation time was at 24 hpm (83.3%) rather than that of 28 hpm(69.6%) and 32 hpm(50.0%). 2. There was no difference among the fusion rates of NT embryos at the voltages of 0.75, 1.0 and 1.5 kV/cm, but the in vitro development rates to morule and blastocyst were significantly (P<0.05) higher at the voltage of 0.75(12.5%) and 1.0kV/cm (12.6%) compared to 1.5kV/cm(0%). 3. No significant difference in activation rates were seen in NT embryos stimulated for 30, 60 and 120 $\mu$sec (71.7, 85.2 and 71.9%, respectively), but the in vitro development rates to morulae and blastocyst were significantly (P<0.05) higher in the oocytes stimulated for 30 $\mu$sec (11.6%) and 60 $\mu$sec(10.7%) than 120 $\mu$sec(0.0%). 4. The fusion rates (71.0 and 87.3%) and the in vitro development rates (9.1 and 12.7%) to morula and blastocyst were seen in the NT embryos stimulated at 28 and 32 hpm under the condition of 1.0 kV/ml, 60 $\mu$sec. However, at 24 hpm the fusion rates were 64.8% and the in vitro development to morula and blastocyst were not seen. 5. The fusion rates between the 8~12, 13~17 and 18~22-cell stage of IVM-IVF embryos were not significantly different. The in vitro development rates of the fused embryos to morula and blastocyst which were received from a blastomere of 8~12, 13~17 and 18~22-cell stages of IVM-IVF embryos were 14.9, 8.3 and 6.5%, respectively. 6. The in vitro development rate of the enucleated recipient oocytes with preactivation (24.2%) to morula and blastocyst was significantly (P<0.05) higher than that of non-preactivation (12.8%). 7. The cell numbers of NT blastocyst and IVM-IVF blastocyst cultured during 7~9 days were 63$\pm$11 and 119$\pm$23, and then their the mean cell cycle number were 5.98 and 6.89, respectively.

• Asian-Australasian Journal of Animal Sciences
• /
• 제27권5호
• /
• pp.635-647
• /
• 2014

Unfertilized oocytes age inevitably after ovulation, which limits their fertilizable life span and embryonic development. Rapamycin affects mammalian target of rapamycin (mTOR) expression and cytoskeleton reorganization during oocyte meiotic maturation. The goal of this study was to examine the effects of rapamycin treatment on aged porcine oocytes and their in vitro development. Rapamycin treatment of aged oocytes for 24 h (68 h in vitro maturation [IVM]; $44h+10{\mu}M$ rapamycin/24 h, $47.52{\pm}5.68$) or control oocytes (44 h IVM; $42.14{\pm}4.40$) significantly increased the development rate and total cell number compared with untreated aged oocytes (68 h IVM, $22.04{\pm}5.68$) (p<0.05). Rapamycin treatment of aged IVM oocytes for 24 h also rescued aberrant spindle organization and chromosomal misalignment, blocked the decrease in the level of phosphorylated-p44/42 mitogen-activated protein kinase (MAPK), and increased the mRNA expression of cytoplasmic maturation factor genes (MOS, BMP15, GDF9, and CCNB1) compared with untreated, 24 h-aged IVM oocytes (p<0.05). Furthermore, rapamycin treatment of aged oocytes decreased reactive oxygen species (ROS) activity and DNA fragmentation (p<0.05), and downregulated the mRNA expression of mTOR compared with control or untreated aged oocytes. By contrast, rapamycin treatment of aged oocytes increased mitochondrial localization (p<0.05) and upregulated the mRNA expression of autophagy (BECN1, ATG7, MAP1LC3B, ATG12, GABARAP, and GABARAPL1), anti-apoptosis (BCL2L1 and BIRC5; p<0.05), and development (NANOG and SOX2; p<0.05) genes, but it did not affect the mRNA expression of pro-apoptosis genes (FAS and CASP3) compared with the control. This study demonstrates that rapamycin treatment can rescue the poor developmental capacity of aged porcine oocytes.

• 한국수정란이식학회지
• /
• 제27권2호
• /
• pp.121-126
• /
• 2012

The objective of this study was to examine the effect of in vitro culture media on embryonic development of in vitro-matured (IVM) oocytes after parthenogenetic activation (PA) in pigs. Immature pig oocytes were matured in TCM-199 supplemented with porcine follicular fluid, cysteine, pyruvate, EGF, insulin, and hormones for the first 22 h and then further cultured in hormone-free medium for an additional 22~26 h. IVM oocytes were activated by electric pulses and cultured in porcine zygote medium-3 (PZM-3) and North Carolina State University-23 supplemented with essential and non-essential amino acids (NCSU-23aa). These media were further modified by supplementing 2.77 mM myo-inositol, 0.34 mM trisodium citrate, and $10{\mu}M$ ${\beta}$-mercaptoethanol (designated as mPZM-3 and mNCSU-23aa, respectively). Culture of PA embryos in mPZM-3 significantly increased development to the blastocyst stage than culture in NCSU-23aa (36.2% vs. 24.8%, p<0.05). Modified PZM-3 showed a significantly higher blastocyst formation than NCSU-23aa in both groups of embryos that were activated at 44 h and 48 h of IVM (51.0% vs. 35.5% and 49.0% vs. 34.2% in oocytes activated at 44 h and 48 h of IVM, respectively). Irrespective of the follicle diameter where oocytes were collected, embryonic development to the blastocyst stage was increased (p<0.05) by the culture in mPZM-3 compared to culture in NCSU-23aa (25.9% vs. 34.2% and 32.9% vs. 44.8% in embryos derived from small and medium size follicles, respectively). Our results demonstrated that culture media had significant effect on preimplantation development PA embryos and that mPZM-3 was superior to mNCSU-23 in supporting development to the blastocyst stage in pigs. This beneficial effect of mPZM-3 on embryonic development was not impaired by other factors such as time of oocyte activation and origin of immature oocytes (small and medium size follicles).

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권10호
• /
• pp.1360-1366
• /
• 2001

The aims of this study were first to evaluate the effects of different levels (20, 40 and 100%) and sources (follicular size: large, >7 mm; medium, >5-7 mm; small, 3-5 mm) of porcine follicular fluid (pFF) on the in vitro maturation (IVM) of porcine oocytes, and the effects of fertilization treatments and different culture conditions on development of fertilized oocytes were also investigated. No differences in the maturation (63.6-76.6%) and cleavage (24.8-34.3%) rates were observed among the 20,40 and 100% pFF groups (p>0.05). The cleavage rates of oocytes cultured and fertilized in 40% and 100% pFF maturation media were significantly higher than those fertilized in m199-NBCS (51.0-61.2% vs. 12.8-31.8%. p<0.05), regardless of sources of the pFF. When oocytes were fertilized in m199-NBCS followed by culture in rabbit oviducts for 4 days, the cleavage rate in 40% pFF group was better than that in 100% pFF group (46.9% vs. 32.5%, p<0.05). Two oocytes recovered from the oviducts in the 40% pFF group developed to blastocysts after IVC. However, none developed to blastocysts when fertilized in the IVM medium after being transferred to rabbit oviducts. In conclusion, addition of pFF accompanied with gonadotropins (FSH, LH) in IVM medium enhanced maturation and cleavage rates of porcine oocytes. Direct addition of sperm suspension to IVM medium may be an alternative to simplify the fertilization procedures and to reduce the mechanical lesion during manipulation. Furthermore, rabbit oviducts provide a better environment for the in vitro fertilized oocyte developing to the morula and blastocyst stages.

• 한국동물생명공학회지
• /
• 제39권2호
• /
• pp.67-80
• /
• 2024

Background: Post-ovulatory aging (POA) of oocytes is related to a decrease in the quality and quantity of oocytes caused by aging. Previous studies on the characteristics of POA have investigated injury to early embryonic developmental ability, but no information is available on its effects on mitochondrial fission and mitophagy-related responses. In this study, we aimed to elucidate the molecular mechanisms underlying mitochondrial fission and mitophagy in in vitro maturation (IVM) oocytes and a POA model based on RNA sequencing analysis. Methods: The POA model was obtained through an additional 24 h culture following the IVM of matured oocytes. NMN treatment was administered at a concentration of 25 μM during the oocyte culture process. We conducted MitoTracker staining and Western blot experiments to confirm changes in mitochondrial function between the IVM and POA groups. Additionally, comparative transcriptome analysis was performed to identify differentially expressed genes and associated changes in mitochondrial dynamics between porcine IVM and POA model oocytes. Results: In total, 32 common genes of apoptosis and 42 mitochondrial fission and function uniquely expressed genes were detected (≥ 1.5-fold change) in POA and porcine metaphase II oocytes, respectively. Functional analyses of mitochondrial fission, oxidative stress, mitophagy, autophagy, and cellular apoptosis were observed as the major changes in regulated biological processes for oocyte quality and maturation ability compared with the POA model. Additionally, we revealed that the activation of NAD⁺ by nicotinamide mononucleotide not only partly improved oocyte quality but also mitochondrial fission and mitophagy activation in the POA porcine model. Conclusions: In summary, our data indicate that mitochondrial fission and function play roles in controlling oxidative stress, mitophagy, and apoptosis during maturation in POA porcine oocytes. Additionally, we found that NAD⁺ biosynthesis is an important pathway that mediates the effects of DRP1-derived mitochondrial morphology, dynamic balance, and mitophagy in the POA model.

• 한국가축번식학회지
• /
• 제21권1호
• /
• pp.71-78
• /
• 1997

본 연구는 체외성숙 직후의 소 미수정란의 활성화 조건을 검토하기 위하여 실시하였다. 체외에서 22~24시간 성숙배양된 소 미수정란을 다양한 활성화 조건으로 처리하였다. 실험 1에서는 성숙직후 난자를 전기자극(1.25kV/cm, 70$\mu$sec$\times$2회), 에탄올(7%, 5분), Ca2+-ionophore(A23187; 10$\mu$M, 5분) 및 cycloheximide(10$\mu\textrm{g}$/ml, 6시간)로 각각 처리하였다. 활성화율은 전기자극, 에탄올 및 A23187 처리시 48.8~54.3%로 비슷하였으나, cycloheximide처리시는 15.9%로 유의적으로(P<0.05) 낮았고, 무처리구인 대조군은 전혀 활성화 되지 않았다. 실험 2에서 체외성숙 미수정란을 전기자극, 에탄올 및 A23187중 2개 또는 3개를 병용처리한 결과, 활성화율은 46.9~63.5%로 나타났다. 실험 3에서는 전기자극, 에탄올 또는 A23187과 cycloheximide를 병용처리한 결과, 대부분의 난자(98.0~100%)가 활성화되었다. 실험 4에서는 실험 3과 같은 조건으로 처리하여 할성화된 난자를 cytochalasin B로 처리하여 2배체배 형성을 유도한 후 체외배양하여 발육율을 검사하였다. 분할율은 79.8~90.4%였으며, 배반포 발육율은 32.1~42.6%로 나타났다. 이러한 결과는 전기자극, 에탄올 또는 A23187과 chcloheximide의 병용처리가 성숙직후 소 미수정란의 활성화에 효과적임을 확증한다.

• 농업과학연구
• /
• 제34권1호
• /
• pp.13-18
• /
• 2007

본 연구는 난자의 채취시기, 배양액에 BSA, cysteine, myoinositol 첨가가 난자의의 체외성숙에 미치는 영향을 조사하였다. 1. 휴지기, 난포기, 황체기로 구분한 난소로부터 채취한 난포란을 배양하였을 때 체외성숙율은 각각 $0.0{\pm}0.0%$, $10.0{\pm}4.1%$와 $5.7{\pm}1.6%$로서 난포기에 채취한 난자가 휴지기와 황체기의 난자에 비해 체외성숙율이 높게 나타났다. 2. 휴지기, 난포기, 황체기 난포로부터 회수한 난자를 5% BSA와 0.1 mM cysteine를 첨가한 TCM-199 배양액에서 배양했을 때 체외성숙율은 각각 $0.0{\pm}0.0%$, $15.8{\pm}4.7%$와 $5.6{\pm}1.5%$로서 난포기의 난자가 가장 높은 체외성숙율을 나타냈다. 3. 휴지기, 난포기, 황체기 난포로부터 회수한 난자를 5% BSA와 10mM myoinositol를 첨가한 TCM-199 배양액에서 배양했을 때 체외성숙율은 각각 $0.0{\pm}0.0%$, $18.4{\pm}4.6%$와 $5.7{\pm}1.9%$로서 난포기 난자의 체외성숙율이 가장 높게 나타냈다.

• 한국수정란이식학회지
• /
• 제32권4호
• /
• pp.267-274
• /
• 2017

Alpha lipoic acid (ALA) is a biological membranes compound. As the antioxidant, it decreases the oxidized forms of other antioxidant substances such as vitamin C, vitamin E, and glutathione (GSH). To examine the effect of ALA on the in vitro maturation (IVM) of porcine oocytes, we investigated intracellular GSH and reactive oxygen species (ROS) levels, and subsequent embryonic development after parthenogenetic activation (PA). Intracellular GSH levels in oocytes treated with 50uM ALA increased significantly (P < 0.05) and exhibited a significant (P < 0.05) decrease in intracellular ROS levels compared with the control group. Oocytes matured with 50 uM of ALA during IVM displayed significantly higher cleavage rates (67.8% vs. 83.4%, respectively), and higher blastocyst formation rates and total cell number of blastocysts after PA (31.6%, 58.49 vs. 46.8%, 68.58, respectively) than the control group. In conclusion, these results suggest that treatment with ALA during IVM improves the cytoplasmic maturation of porcine oocytes by increasing the intracellular GSH levels, thereby decreasing the intracellular ROS levels and subsequent embryonic developmental potential of PA.

• Reproductive and Developmental Biology
• /
• 제31권2호
• /
• pp.77-82
• /
• 2007

This study was conducted to investigate the effects of oocyte maturational age and activation condition on in vitro development of porcine parthenogenetic embryos (parthenotes). Porcine follicular oocytes were matured in vitro for 30 to 44 hr. Maturation rate was examined during in vitro maturation (IVM) every 2 hr interval. The cdc2 kinase activity was measured at 36 and 44 hr of IVM. Some oocytes were activated at 36 or 44 hr of IVM by three different conditions; 1) single electric stimulation (1.5 kV/cm for $30{\mu}sec$; ES), 2) double electric stimulations (1.5 kV/cm for $30{\mu}sec$, followed by 1.0 kV/cm for $50{\mu}sec$ after 1 hr; ES+ES) or 3) ES+ES followed by culture in 6-dimethlyaminopurine (6-DMAP) for 4 hr (ES+ES+D), and cultured for 6-7 days. Maturation rate was significantly increased as culture period was increased to 36 hr (66.9%, p<0.05), and then gradually increased to 87.1% at 44 hr of IVM. The cdc2 kinase activity was decreased (p<0.05) with culture period prolonged from 36 hr to 44 hr. Lower blastocyst formation rate (4.3%, p<0.05) were obtained by ES in 36 hr-matured oocytes compared to other treatments (16.5 and 20.5%) in the same age and the same treatment in 44 hr-matured oocytes (15.0%). High blastocyst formation rate (23.6%) was obtained by ES+ES+D in 44 hr-matured oocytes (p<0.05). These results demonstrate that porcine oocyte activation and in vitro development of parthenotes can be affected by interactions between oocyte maturational age and activation condition.

• Asian-Australasian Journal of Animal Sciences
• /
• 제15권12호
• /
• pp.1695-1701
• /
• 2002

The purposes of this study were to optimize the in vitro maturation (IVM) and culture (IVC) systems of rabbit oocytes. Cytoskeletal structures in the germinal vesicle stage (GV) and during IVM are also investigated. Ovaries were transported from local slaughterhouses and the cumulus-oocyte complexes (COCs) were collected from ovarian follicles (${\geq}1mm$). COCs were randomly allocated to TCM199-based medium ($T_1$, TCM-199) supplemented with $NaHCO_3$, glucose, sodium pyruvate and FSH ($T_2$), $T_2+E_2+LH$ ($T_3$), $T_3+FBS$ ($T_4$), or $T_1+E_2+LH+FSH+FBS$ ($T_5$), for IVM. In Experiment 1, COCs were retrieved from the follicles and 51 GV oocytes were fixed in the fixative (MTSB-XF) for nuclear and cytoplasmic examinations. In Experiment 2, progressive changes of both the nucleus and the cytoskeleton were examined at 0, 6, 16, and 20 h after IVM. Maturation (MR) and developmental rates were assessed in Experiment 3. Cytoplasmic microtubules (MT) were clearly observed in rabbit GV oocytes. To our knowledge, this is the first report that describes the appearance of MT structures in the GV stage ooplasm. Tremendous variations in cytoskeletal alterations were observed among treatments with the exception of the vitelline ring (VR), which is constantly visible and unchanged during maturation. Germinal vesicle breakdown (GVBD) does not occur at 6 h after onset of maturation culture. When the oocytes for IVM were collected within 2 h, results from Experiment 3 showed that rates of nuclear maturation were 42, 8, 42, 37 and 65% at 16 h of IVM for $T_1$ through $T_5$, respectively, in which $T_1$, $T_4$ and $T_5$ had significantly greater MR than those in other groups (p<0.05). Morula/blastocyst development after parthenogenetic activation ranged from 20 to 63% with significantly greater rates in $T_3$, $T_4$ and $T_5$ (p<0.05). These results suggested that oocytes recovered from slaughterhouse ovaries can be matured and parthenogenetically activated in vitro, but the MR remained low in this study. Addition of $E_2$ and LH in the medium may be beneficial for cytoplasmic maturation, but FBS exerts a nega- tive role in the subsequent development of parthenogenetic embryos when energy substrates are provided in the IVC media. More studies are required for improving the MR and further development of the GV stage rabbit oocytes.