The present study was performed to investigate the effects of in vitro maturation (IVM) and in vitro fertilization (IVF) duration on the development of Korean Native Cattle embryos. The time of blastocyst formation and the quality of blastocysts based on cell numbers were examined. The cleavage rate increased with the length of IVF duration in the groups of 18-hr IVM, but was constant in the groups of 24-hr IVM. The development rate to the 8-cell stage was significantly higher in the IVM 18: IVF 20 group than in the IVM 24: IVF 24 group. The development rate to the blastocyst stage was highest in the IVM 18: IVF 20 group, significantly different from that of the IVM 18: IVF 16, IVM 24: IVF 20 and IVM 24: IVF 24 group. The time of blastocysts formation tended to be shorter when IVM and IVF duration were decreased. The number of inner cell mass, trophoblast and the total cells were significantly higher in the IVM 18: IVF 16 group than in the IVM 24: IVF 24 group (P<0.05). These results demonstrated that the IVM and IVF duration should be adequate for the efficient production of bovine embryos, and it might particularly be essential to determine the proper combination of IVM and IVF duration.
Cellular cyclic adenosine-3' 5'-monophosphate (cAMP) modulator is known as meiotic inhibitor and can delays spontaneous maturation in IVM experiment. Among many cAMP modulators, the role of Pituitary adenylate cyclase activating polypeptide (PACAP) on IVM isn't known. The purpose of this study is to improve the maturation of oocytes derived from follicles ${\leq}3mm$ in diameter through PACAP as meiotic inhibitor during pre-in vitro maturation (pre-IVM). First, we checked PACAP and its receptors in cumulus cells and, to establish the optimal phase and concentration of PACAP for pre-IVM, we conducted chromatin configuration assessments. As a result, the rate of GV (Germinal Vesicle) according to duration of pre-IVM was significantly decreased 12 h and 18 h after IVM (87.1 and 84.1%, respectively) compared to 0 h (99.4%). When COC was cultured for 18 h, the GV rate in the $1{\mu}M$ of PACAP treatment group (82.1%) was significantly higher than any other PACAP treatment groups (60.5, 64.1, 74.4 and 69.9 %, respectively). So, we divided into four groups as follows; MF (the conventional IVM group, obtained from follicle from 3 to 6 mm in diameter), SF (the conventional IVM group, obtained from follicle ${\leq}3mm$ in diameter), Pre-SF(-)PACAP (IVM group including 18 h pre-IVM without $1{\mu}M$ of PACAP, obtained from follicle ${\leq}3mm$ in diameter) and Pre-SF(+)PACAP (IVM group including 18 h pre-IVM with $1{\mu}M$ of PACAP, obtained from follicle ${\leq}3mm$ in diameter). To examine the effect of PACAP during pre-IVM, we investigated analysis of nuclear maturation, intracellular glutathione (GSH) and reactive oxygen species (ROS) levels. In cumulus cells, PACAP receptors, ADCYAP1R1 and VIPR1 were detected but were not detected in oocytes. After IVM, the Pre-SF(+)PACAP had the highest Metaphase II rate (91.7%) among all groups (P<0.05). The GSH levels in the MF and Pre-SF(+)PACAP were significantly higher than in the other groups (P<0.05) and ROS levels was no significant difference among all groups. In conclusion, these results indicated that even though the oocytes were derived from SF, pre-IVM application of PACAP improved meiotic and cytoplasmic maturation by regulating intracellular oxidative stress.
Kim, Jin-Woo;Park, Hyo-Jin;Jung, Jae-Min;Yang, Seul-Gi;Kim, Min-Ji;Kim, In-Su;Jegal, Ho-Geun;Koo, Deog-Bon
Journal of Embryo Transfer
/
v.33
no.4
/
pp.287-296
/
2018
Ganglioside GM3 is known as an inhibition factor of cell differentiation and proliferation via inhibition of epidermal growth factor receptor (EGFR) phosphorylation. Our previous study showed that the exogenous ganglioside GM3 reduced the meiotic maturation of porcine oocytes and induced apoptosis at 44 h of in vitro maturation (IVM). However, the role of ganglioside GM3 in the relationship between EGFR signaling and apoptosis during porcine oocyte maturation has not yet been studied. First, porcine cumulus-oocyte complexes (COCs) were cultured in the NCSU-23 medium with exogenous ganglioside GM3 according to maturation periods (non-treated, only IVM I: 0 - 22 h, only IVM II: 22 - 44 h and IVM I & II: 0 - 44 h). We confirmed that the proportion of germinal vesicle breakdown (GVBD) increased significantly in the IVM I treated group than in the control group. We also confirmed that the meiotic maturation until M II stage and polar body formation decreased significantly in the only IVM I treated group. Cumulus cell expansion and mRNA levels of the expansion-related factors (HAS2, TNFAIP6 and PTX3) decreased significantly in the IVM I treated group than in the control group. Protein levels of EGFR, p-EGFR, ERK1/2, and p-ERK1/2 decreased significantly in the GM3-treated groups, during the IVM I period. In addition, cellular apoptosis, determined using TUNEL assay, and protein levels of Cleaved caspase 3, were increased significantly in the GM3-treated COCs during the IVM I period. Based on these results, ganglioside GM3 exposure of porcine COCs during the IVM I period reduced meiotic maturation and cumulus cell expansion via inhibition of EGFR activity in pigs.
Camel (camelus dromedarius) is a unique large mammalian species that can survive harsh environmental conditions and produce milk, meat, and wool. Camel reproduction is inferior when compared to other farm animal species such as cattle and sheep. Several trials have been reported to increase camel reproduction and production through assisted reproductive techniques (ARTs) such as in vitro fertilization and cloning. For these reasons, obtaining enough mature oocytes is a cornerstone for ARTs. This demand would be improved by the oocyte in vitro maturation (IVM) systems. In this review, the current approaches and views from different laboratories using ARTs and the IVM to produce embryos in vitro in camel species. For the last two decades, conventional IVM system was the common approach, however, recently the bi-phasic IVM system has been introduced and showed promising improvement in IVM of camel oocytes. Detailed studies are needed to understand camel meiosis and IVM to efficiently increase the production of this species.
This study was carried out to investigate the effects of the supplementation of glutamine, glucosamine and glutathione on the porcine oocytes on IVM rates. Cocs were incubated in NCSU-23 supplemented with at $2.0{\sim}10.0\;mM$ glucosamine, $0.5{\sim}4.0\;mM$ glutamine and $0.1{\sim}1.0\;mM$ glutathione for 48 hrs. Oocytes were transferred to 50 ul drops of maturation medium covered with mineral oil and cultured in a $CO_2$ incubator ($38^{\circ}C$, 5% $CO_2$, 95% air). The IVM rates of oocytes cultured in NCSU-23 supplemented with 0.5, 1.0, 2.0 and 4.0 mM glutamine for 48 hrs were $46.0{\pm}4.5%$, $52.0{\pm}4.8%$, $50.0{\pm}4.2%$ and $44.0{\pm}4.5%$, respectively. The IVM rates of oocytes cultured in NCSU-23 supplement with 2.0, 5.0, 7.0, 10.0 mM glucosamine for 48 hrs were $44.0{\pm}4.5%$, $42.0{\pm}4.5%$, $38.0{\pm}4.6%$ and $24.0{\pm}4.8%$, respectively. The IVM rates of oocytes cultured in NCSU-23 supplemented with glucosamine were no significantly increased compare to the control ($42.5{\pm}4.0%$). The IVM rate of oocytes cultured in NCSU-23 supplemented with 3.0, 5.0, 7.0, 10.0 mM glutathione for 48 hrs were $40.0{\pm}3.2%$, $54.0{\pm}4.2%$, $48.0{\pm}4.5%$, $44.0{\pm}4.8%$, respectively. The IVM rate of oocytes cultured in NCSU-23 supplemented with glutamine and glutathione were significantly increased co~pared to those control ($42.5{\pm}4.0%$). Glucosamine did not affect the IVM rates of oocytes. IVM rates of oocytes cultured in NCSU-23 medium for 48 hrs were significantly increased compared to the cultured for 40 hrs.
This study was carried out to investigate the effect of morphology of oocytes, kinds of media, cysteine and myo-inositol supplementation on IVM rate of porcine oocytes. Cumulus- enclosed oocytes were incubated in maturation NCSU-23 and TCM-199 medium with supplementation with 3, 5, 10, 20 mM myo-inositol and 0.05, 0.1, 0.5, 1.0 mM cysteine. 1. When classified by morphology, excellent, good and fair of cumulus-enclosed oocytes were incubated for 48 hrs and the IVM rate were $14.2{\pm}3.7%{\sim}58.7{\pm}4.0%$, respectively. The rate were greater in oocytes with excellent cumulus cells than those without cumulus cells. 2. The IVM rate of oocytes cultured in TCM-199 and NCSU- 23 medium supplementation or non-supplementation with 1.0 mM myo-inositol were $7.5{\pm}4.5%,\;45.0{\pm}4.8%\;and\;4.4%,\;42.5{\pm}4.2%,\;18.0{\pm}5.2%$, respectively. Supplementation with myo-inositol significantly increased the IVM rate of oocytes. 3. The IVM rate of oocytes cultured in NCSU-23 medium supplementation of 3, 5, 10, 20 mM myo-inositol for 48 hrs were $47.5{\pm}4.5%,\;57.5{\pm}4.2%,\;62.5{\pm}4.9%,\;50.0{\pm}5.2%$, respectively. The IVM rate of oocytes in NCSU-23 medium supplemented with 10 mM myo-inositol were significantly increased compared to control ($42.5{\pm}4.0%$). 4. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 media supplement with 0.3, 0.5, 1.0, 2.0 mM myo-inositol were $50.0{\pm}4.5%,\;62.5{\pm}4.2%,\;52.5{\pm}4.9%,\;45.0{\pm}4.2%$, respectively. The IVM rate of oocytes in NCSU-23 medium supplemented with 10 mM cysteine were significantly increased compared to control ($42.5{\pm}4.0%$).
The aim of present study was to investigate regulatory mechanism of alpha-linolenic acid (ALA) during in vitro maturation (IVM) on nuclear and cytoplasmic maturation of porcine oocytes. Basically, immature cumulus-oocyte complexes (COCs) were incubated for 22 h in IVM-I to which hormone was added, and then further incubated for 22 h in IVM-II without hormone. As a result, relative cumulus expansion was increased at 22 h after IVM and it was enhanced by treatment of ALA compared with control group (p < 0.05). During IVM process within 22 h, cAMP level in oocytes was decreased at 6 h (p < 0.05) and it was recovered at 12 h in ALA-treated group, while oocytes in control group recovered cAMP level at 22 h. In cumulus cells, it was reduced in all time point (p < 0.05) and ALA did not affect. Treatment of ALA enhanced metaphase-I (MI) and MII population of oocytes compared with oocytes in control group at 22 and 44 h, respectively (p < 0.05). Intracellular GSH levels in ALA group was increased at 22 and 44 h after IVM (p < 0.05), whereas it was increased in control group at 44 h after IVM (p < 0.05). In particular, the GSH in ALA-treated oocytes during 22 h of IVM was higher than control group at 22 h (p < 0.05). Lipid amount in oocytes from ALA group was higher than control group (p < 0.05). Treatment of ALA did not influence to absorption of glucose from medium. Cleavage and blastocyst formation of ALA-treated oocytes were enhanced compared with control group (p < 0.05). These findings suggest that supplementation of ALA could improve oocyte maturation and development competence through increasing GSH synthesis, lipid storage, and regulation of cAMP accumulation during early 22 h of IVM, and these might be mediated by cumulus expansion.
Lim, Kyung Sil;Chae, Soo Jin;Choo, Chang Woo;Ku, Yeon Hee;Lee, Hye Jun;Hur, Chang Young;Lim, Jin Ho;Lee, Won Don
Clinical and Experimental Reproductive Medicine
/
v.40
no.4
/
pp.143-147
/
2013
Oocyte in vitro maturation (IVM) is an assisted reproductive technology in which oocytes are retrieved from the antral follicles of unstimulated or minimally stimulated ovaries. IVM of human oocytes has emerged as a promising procedure. This new technology has advantages over controlled ovarian stimulation such as reduction of costs, simplicity, and elimination of ovarian hyperstimulation syndrome. By elimination or reduction of gonadotropin stimulation, IVM offers eligible infertile couples a safe and convenient form of treatment, and IVM outcomes are currently comparable in safety and efficacy to those of conventional in vitro fertilization. IVM has been applied mainly in patients with polycystic ovary syndrome or ultrasound-only polycystic ovaries, but with time, the indications for IVM have expanded to other uncommon situations such as fertility preservation, as well as to normal responders. In this review, the current clinical experiences with IVM will be described.
Fesahat, Farzaneh;Firouzabadi, Razieh Dehghani;Faramarzi, Azita;Khalili, Mohammad Ali
Clinical and Experimental Reproductive Medicine
/
v.44
no.2
/
pp.79-84
/
2017
Objective: Optimizing in vitro maturation (IVM) media to achieve better outcomes has been a matter of interest in recent years. The aim of this prospective clinical trial was to investigate the effects of different media on the IVM outcomes of immature oocytes at the germinal vesicle (GV) stage. Methods: A total of 400 immature oocytes at the GV stage with normal morphology were retrieved from 320 infertile women aged $31{\pm}4.63years$ during stimulated intracytoplasmic sperm injection (ICSI) cycles. They were divided into groups of homemade IVM medium (I, n = 100), cleavage medium (II, n = 100), blastocyst medium (III, n = 100), and Sage IVM medium (IV, n = 100) and cultured for 24 to 48 hours at $37^{\circ}C$. ICSI was performed, and the rates of fertilization and embryo formation were compared across the four groups. Results: In the 400 retrieved GV oocytes, the total maturation rates showed significant differences in groups I to IV (55%, 53%, 78%, and 68%, respectively, p<0.001). However, there were no significant differences in the fertilization, embryo formation, or arrest rates of metaphase II oocytes across these groups. In all groups, GV maturation was mostly completed after 24 hours, with fewer oocytes requiring 48 hours to mature (p<0.01). Moreover, the rate of high-quality embryos was higher in group IV than in the other groups (p=0.01). Conclusion: The quality of the IVM medium was found to affect clinical IVM outcomes. Additionally, blastocyst medium may be a good choice in IVM/ICSI cycles as an alternative IVM medium.
The present study was performed to investigate the first polar body(PB) extrusion during in-vitro maturation(IVM) and to examine the effect of different maturation time on the embryo development of Korean Native Cows(KNC) with regard to blastocyst(BL) cell numbers and pregnancy rates. PB extrusion did not take place for the first 12 hours(hr) of IVM, and most of KNC oocytes extruded PB from 14 to 20 hr after the onset of maturation. There was no significant difference in cleavage and 8-cell stage rates among the treatment groups, but BL and BL/8-cell rates were significantly higher(P<0.05) in 18 hr maturation group(31.0$\pm$5.7 and 82.0$\pm$5.1%) than 22 and 24 hr maturation group. The proportion of BL formed on day 7 and 8 was significantly higher(P<0.05) in 18 hr maturation group(85%) than in 24 hr maturation group(55%). There was a significant difference(P<0.05) in inner cell mass, trophectoderm and total cell number between day 7 BL produced by in-vivo and IVM 18 hr and day 8 BL produced by IVM 18 hr and 24 hr. Pregnancy rates are also significantly higher(P<0.05) in in-vivo(56.3%) and IVM 18 hr day 7(50.0%) group than day 8 treatment groups(18 hr: 16.7%, 24 hr: 10.5%). These results suggest that KNC oocytes achieve developmental competency within 20 hr of IVM, and "short" IVM (18 hr) is more effective than "long" IVM(24 hr) in embryo development rates, BL cell numbers and pregnancy rates.
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