• Reproductive and Developmental Biology
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• 제28권2호
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• pp.95-99
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• 2004

본 연구는 미성숙돼지 난모세포의 체외 성숙에 있어서 myo-inositol의 영향을 알아보기 위하여 실시하였다. 미성숙 돼지 난모세포을 myo-inositol을 포함하는 또는 포함하지 않은 체외 성숙배지에서 44시간 체외 성숙을 유도하였을 때 성숙율은 myo-inositol을 첨가한 성숙배지에서 성숙시킨 실험구에 유의하게 높았다(P<0.05). Myo-inositol 에 의한 성숙율 향상에 있어서 난구세포의 영향을 알아보기 위하여 난구세포의 치밀도에 따라 분류하여 미성숙 난모세포을 myo-inositol을 포함하는 체외 성숙배지에서 배양하였을 때 난구세포가 치밀한 미성숙 난모세포에서가 더 높은 성숙율을 나타내었다(P<0.05). 그러나 난구세포가 치밀하지 않은 미성숙 난모세포도 myo-inositol을 포함하는 성숙배지에서 배양하면 성숙율은 대조구에 비하여 유의하게 높았다(P<0.05). 이러한 결과는 돼지 난모세포의 체외 성숙배지에 myo-inositol의 첨가는 체외 성숙율을 향상시킬 수 있음을 나타내고 있다.

• 한국수산과학회지
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• 제56권3호
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• pp.309-314
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• 2023

Shark populations are constantly decreasing owing to environmental destruction and overfishing; thus, sharks are now at risk of extinction, with 30.5% of species classified as endangered on the International Union for Conservation of Nature's Red List. Sharks are apex predators and keystone species in balancing the marine food chain; their extinction would create an imbalance in the entire marine ecosystem. Assisted reproductive technology is a last resort for protecting animals facing extinction. Here, as a proactive effort toward building a hormone-induced artificial insemination protocol for endangered wild sharks, we identified the possibility of germ cell maturation by administration of GnRH, a commercially produced synthetic salmon gonadotropin-releasing hormone, and calculated its optimum dosage and injection timing. The experiment was conducted on one shark species, Chiloscyllium plagiosum. Injections were administered in 24 h intervals to C. plagiosum females, and 0.2 mL/kg+0.2 mL/kg were the optimal doses. These doses effectively induced maturation and, and ovulation, and oocyte release. Our results confirm that GnRH is a suitable tool for shark hormone-induced artificial insemination and indicate that this method may facilitate the conservation of endangered shark species.

• Animal cells and systems
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• 제5권1호
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• pp.51-57
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• 2001

We have previously shown that oocyte maturation is induced by an immobilized progesterone, progesterone-3-carboxymethyloxime - bovine serum albumin conjugate (P-BSA) in Rana dybowskii. In this study, we confirmed the maturation inducing activity of P-BSA on Xenopus oocyte and examined the binding character of the immobilized progesterone on the surface of Xenopus oocytes after removal of the vitelline layer. P-BSA induced maturation of Xenopus oocytes but E-BSA failed to do so as observed in Rana. Binding of the immobilized progesterone, fluorescein isothiocyanate-labeled progesterone-3-0-carboxymethyloxime-BSA (P-BSA-FITC) on the devitellined oocytes surface was examined by fluorescence confocal microscopy. The binding affinity of P-BSA-FITC to the devitellined oocyte was higher than that of estrogen-BSA-FITC (E-BSA-FITC) or testosterone-BSA-FITC (T-BSA-FITC). The binding disappeared in the presence of excess free progesterone but not in the presence of free estrogen. Maximum binding occurred after two-hours of incubation with P-BSA-FITC at pH 7.5. Stronger binding occurred in oocytes at stage Vl than stage IV, and in vitro treatment of hCG enhanced the binding. Taken together, these results suggest that a specific receptor for progesterone exists on the plasma membrane of Xenopus oocytes and that progesterone acts initially on this putative receptors and triggers generation of membrane-mediated second messengers during the early stage of oocyte maturation In amphibians.

• 한국어류학회지
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• 제12권1호
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• pp.46-53
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• 2000

돌돔 Oplegnathus fasciatus의 인위적인 성 성숙 및 산란 유도를 위한 연구에서, 3년생 돌돔 친어를 대상으로 수온 및 광주기 조절에 의한 생식소 발달을 조직학적으로 조사하였다. 수온 및 광주기 조절구 (Exp. I)는 1996년 12월부터 1997년 2월까지 수온은 $14.5^{\circ}C$에서 $21.0^{\circ}C$ 그리고 광주기는 10 : 30 L에서 15 : 30 L로 증가시킨 후 4월까지 계속 유지시켰다. 수온 조절구 (Exp. II)에서 수온은 Exp. I과 동일하게 조절하였고, 광주기는 3월 초순까지는 자연 광주기로 조절하였다가 이후 장일 광주기 (15 : 30L)로 재조절 하였다. 대조구는 1996년 12월부터 1997년 4월까지 해상 가두리의 자연 조건하에서 사육하였다. 생식소 활성은 1 월부터 Exp. I, II 모두에서 시작되었다. 그리고 성숙과 산란은 Exp. I에서는 수온과 광 주기가 각각 $21.0^{\circ}C$와 15 : 30L까지 도달한 2월부터 시작되었으나, Exp. II는 3월 초순까지도 부분적 성숙만 유도되다 장일 광주기 (15 : 30 L)로 조절한 후 3월 하순 부터는 성숙과 산란이 시작되었다.

• 생명과학회지
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• 제27권10호
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• pp.1097-1103
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• 2017

뱀장어(Anguilla japonica)의 인공종묘생산은 연어뇌하수체추출물(SPE, salmon pituitary extract)을 암컷 뱀장어에게 지속적인 투여를 하고 인위적으로 성성숙을 유도로 얻은 난과 정자를 인공수정을 하고 부화 시켜 생산한다. 하지만 SPE를 반복적으로 복강에 주사하는 방법은 암컷 뱀장어에게 많은 스트레스를 주며, 결국 스트레스로 인하여 완전한 성성숙을 하지 못하고 폐사에 이르게 되거나 배란한 난의 질이 좋지 않아 부화율과 자어의 생존율이 떨어지는 문제점을 갖고 있다. 본 연구에서는 뱀장어의 성성숙 유도에 유효하다고 알려진 호르몬이 주입된 osmotic pump를 복강에 삽입 후 암컷 뱀장어의 성성숙 유도를 하였다. 본 연구결과 SPE를 투여한 실험어의 GSI가 hCG, GnRHa, MT를 각각 또는 함께 투여한 실험구 보다 유의하게 증가하였으며 조직학적 분석결과에서도 난소의 난모세포가 핵이동기 단계로 발달되었음을 관찰할 수 있었다. 본 결과를 통해 osmotic pump를 이용한 암컷 뱀장어 인위적 성성숙 유도 방법으로 이용 가능할 것으로 생각된다.

• Clinical and Experimental Reproductive Medicine
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• 제18권2호
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• pp.153-162
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• 1991

The present study was undertaken to clarify the role of calcium ion as a factor for the maturation of follicle-enclosed mouse oocytes. Follicles were isolated with two sharp needles under a stereomicroscope from mouse(ICR) ovaries which were treated PMSG 5 IU 45 hours previously. Isolated follicles were cultured for 14-16 hours in an organ culture system at $37^{\circ}C$, 5% $CO_2$ in air and in a 100% humidified incubator by treatment of hCG, EDTA and $^{45}Ca^{++}$. Culture medium was Modified Hank's Balanced Salt Sol. (MHBS) and addition of hCG (human chorionic gonadotropin) was made into two doses level 0.4 IU and 0.8IU from the stock sol. and also $^{45}Ca^{++}$ was treated in the culture medium. To explain the role of calcium, calcium chelating agent EDTA was treated to the culture of the mouse follicle-enclosed oocytes. Two observations were made in the present study; nucleus phase and $^{45}Ca^{++}$ uptake into the oocyte. HCG induced oocyte maturation in the follicle about two folds as much as the control group, whereas there is no difference in oocyte maturation between 0.4 IU and 0.8 IU of hCG. Optimum level of hCG seems to be 0.4 IU/ml in the mouse follicle culture. HCG stimulated $^{45}Ca^{++}$ uptake into the oocyte of the follicles by two folds. $^{45}Ca^{++}$ uptake in the control group is about 2.5 folds in comparison of the EDTA(1.71mM) treated group. However, calcium uptake in the EDTA treated groups tends to increase depending on the decrease of EDTA concentration. These observations suggest that firstly, hCG stimulates maturation of the oocyte of the follicle, secondly, $Ca^{++}$ influx is induced by hCG and thirdly, $Ca^{++}$ influx by the treatment of EDTA decreases as a dosage-dependent process. This $Ca^{++}$ uptake may take place by the changes of permeability which was induced by hCG treatment. That is, $Ca^{++}$ influx may trigger the resumption of oocyte maturation. It is further necessary in the future study how this $Ca^{++}$ uptake is induced by hCG and increases permeability of the follicle and oocyte.

• 한국수정란이식학회지
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• 제33권4호
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• pp.287-296
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• 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.

• Molecules and Cells
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• 제45권12호
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• pp.923-934
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• 2022

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have great potential in applications such as regenerative medicine, cardiac disease modeling, and in vitro drug evaluation. However, hPSC-CMs are immature, which limits their applications. During development, the maturation of CMs is accompanied by a decline in their proliferative capacity. This phenomenon suggests that regulating the cell cycle may facilitate the maturation of hPSC-CMs. Aurora kinases are essential kinases that regulate the cell cycle, the role of which is not well studied in hPSC-CM maturation. Here, we demonstrate that CYC116, an inhibitor of Aurora kinases, significantly promotes the maturation of CMs derived from both human embryonic stem cells (H1 and H9) and iPSCs (induced PSCs) (UC013), resulting in increased expression of genes related to cardiomyocyte function, better organization of the sarcomere, increased sarcomere length, increased number of mitochondria, and enhanced physiological function of the cells. In addition, a number of other Aurora kinase inhibitors have also been found to promote the maturation of hPSC-CMs. Our data suggest that blocking aurora kinase activity and regulating cell cycle progression may promote the maturation of hPSC-CMs.

• 한국발생생물학회지:발생과생식
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• 제27권3호
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• pp.127-135
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• 2023

Effects of changes in photoperiod on the reproductive events in fish are suggested to be mediated mainly via the action of melatonin (MEL). Changing levels of plasma MEL throughout the day and year are suggested to influence the hypothalamus-pituitary-gonadal axis in fish. Therefore, in this study, we aimed to investigate the effects of MEL on oocyte maturation and germinal vesicle breakdown (GVBD) in the marine fish, Chaenogobius annularis, in vitro. Oocytes at three different stages (pre-, mid-, and late-vitellogenesis) were incubated with (a) only MEL (5, 10, 50, 100, 500, and 1,000 pg/mL) and (b) 50 pg/mL of 17α,20β-dihydroxy-4-pregnen-3-one (17α20βP), maturation-inducing hormone (MIH) of this species, and MEL (4-h incubation before addition of MIH). Any single MEL treatment did not significantly induce GVBD. However, treatment with 50 pg/mL MEL or MIH significantly induced GVBD. These results suggest that preincubation with MEL accelerates the effect of MIH on longchin goby oocyte maturation.

• ALGAE
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• 제18권3호
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• pp.217-223
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• 2003

Seasonal growth and maturation process of Caulerpa okamurae were investigated in natural populations and in culture. Monthly sampling was carried out by SCUBA diving at Baekunpo, Busan, southeastern coast of Korea from November 1999 to October 2001. Growth of erect branches depended mainly on the water temperature in the natural habitat. Maximum length of erect branches was 14.0 $\pm$ 1.4 cm in June 2001 when the water temperature was 19.7$^{\circ}C$ and minimum was 2.8$\pm$0.2 cm in April when the water temperature was 14.7$^{\circ}C$. Fresh weight of erect branches was 3.9 $\pm$ 0.5 g in June 2001 and 0.2 $\pm$ 0.04 g in September 2000. Biomass of the population was maximum of 922.5 g dw${\cdot}m^{-2}$ in July and minimum of 125.6 g dw${\cdot}m^{-2}$ in April. Gametangial network was observed on the ramuli when the water temperature was over 19$^{\circ}C$ in August 2000 and June 2001. In the culture regime of 4 temperatures (15, 20, 25 and 30$^{\circ}C$) and 3 irradiances (20, 50 and 80 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$) combination, the maturation of excised erect branches was mainly affected by temperature. Maturation was induced under all irradiance conditions at 20 and 25$^{\circ}C$; under 80 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$ at 15$^{\circ}C$; and under 20 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$ at 30$^{\circ}C$. The highest rate of maturation was 64% under 20 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$ at 25$^{\circ}C$. These results suggested that developmental initiations of C. okamurae occurred at higher than 13$^{\circ}C$ and maturation took about 270 degree-days.