• Development and Reproduction
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• v.27 no.3
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• pp.149-157
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• 2023

We investigated the involvement of autophagy with steroidogenesis in testicular Leydig cells. Human chorionic gonadotropin (hCG)-stimulated T production in Leydig cells was not remarkably altered in the presence of an autophagy inhibitor 3-methyladenine (3-MA). Although pretreatment with 3-MA demonstrated a tendency to decrease hCG-induced T production, the differences were significant only at a higher time point of 24 h following hCG. Microtubule associated protein light chain 3 (LC3)-II was detectable in the control cells in all the experiments. The hCG-induced increase in steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleave (P450scc) protein levels were not significantly altered by 3-MA. Leydig cells isolated from immature rat testes 12 h following hCG treatment showed relatively increased levels of LC3-II protein compared to the control group. Furthermore, LC3-II levels shown in these cells reached almost the identical to those from normal adult testes. However, LC3-II protein levels were almost comparable or even slightly lower than the controls at 48 h following hCG. Expression of StAR and P450scc was upregulated at both 12 and 48 h after hCG. We also used MA-10 cells, the mouse Leydig cell line, in this experiment. When dibutyryl cyclic-AMP was treated with MA-10 cells, P4 levels were significantly increased in the cell culture medium. However, P4 levels tended to decrease in the presence of 3-MA, but the difference was not statistically significant. This was consistent with the results of the rat Leydig cell experiments. Together, we believe that although autophagy participates in steroidogenesis and enhances steroidogenic efficacy of Leydig cells, it may not be a decisive cellular process for steroidogenesis, specifically in the mature Leydig cells.

• Journal of Life Science
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• v.24 no.10
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• pp.1039-1045
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• 2014

This study analyzed whether human chorionic gonadotropin (hCG) induces ER stress via the IRE/XBP1 pathway in mouse Leydig tumor (mLTC-1) cells. In a previous study, we demonstrated that the unfolding protein response (UPR) plays an important role in the expression of steroidogenic enzymes by modulating the ATF6 pathway, as well as ER stress-mediated apoptosis in hCG-stimulated Leydig cells. Although UPR signaling has been reported to regulate the IRE1/XBP1 pathway, it is not known whether hCG-induced ER stress in Leydig cells can activate the pathway. To investigate the activation of the IRE1/XBP1 pathway in mLTC-1 cells after hCG treatment, we performed a Western blot analysis to detect the phospho-IRE1 protein and an RT-PCR analysis to validate splicing of XBP1 mRNA. We used ER stress-activated indicator (ERAI) constructs for monitoring the activity of IRE1 and then analyzed by fluorescence microscopy and flow cytometry. The expression levels of the phospho-IRE1 protein markedly increased in response to the hCG treatment. In the mLTC-1 cells transfected with an F-XBP1-venus/F-$XBP1{\Delta}DBD$-venus construct, the hCG treatment led to the appearance of green fluorescent cells and detectable fluorescence in the nucleus and cytosol, respectively. In addition, splicing of XBP1 mRNA significantly increased after the hCG treatment. Taken together, these results indicate that hCG-induced ER stress leads to activation of the IRE1/XBP pathway in Leydig cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.203-210
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• 1997

The aim of this study was to determine the effect of steroids and human chorionic gonadotropin (HCG) on in vitro maturation and ovulation of oocyte in Pseudobagrus fulvidraco. Oocytes were incubated in the media Leibovitz L15 supplemented with the various concentration of $17\alpha,\;20\beta-dihydroxy-4-pregnen-3-one(17\alpha20{\beta}OHP),\;17\alpha-hydroxyprogesterone(17{\alpha}OHP),\;progesterone(P_4),\;estradiol-17\beta(E_2)and\;HCG$. After 60 hours incubation, the maturation ability of oocyte was assessed by the appearance of germinal vesicle breakdown (GVBD). GVBD was significantly enhanced by the addition of $17\alpha20{\beta}OHP,\;17{\alpha}OHP,\;P_4\;and\;HCD(P<0.05)$. The highest CVBD was observed when $17\alpha20{\beta}OHP$ and HCG were supplemented to media. When oocytes were cultured for 16 hours in media containing $10\~1,000\;ng/ml\;17\alpha20{\beta}OHP,\;17{\alpha}OHP\;and\;P_4$, the rate of GVBD in oocytes cultured in the medium supplemented with 100 ng/ml $17\alpha20{\beta}OHP(65\%)$ was significantly higher than that with $17{\alpha}OHP\;(40\%)\;and\;P_4(35\%)$. The efforts of $17\alpha20{\beta}OHP$ and HCG on GVBD were assessed by various concentration of these hormones. When oocytes were cultured for 60 hours in various media containing $1\~1,000\;ng/ml\;17{\alpha}20{\beta}OHP\;or\;5\~1,000\;IU/ml$ HCG, the GVBD of oocytes was significantly increased in the medium with $10\~100\;ng/ml\;17\alpha20{\beta}OHP$ and 500 IU/ml HCT. When oocytes were cultured in the various media supplemented with $1\~1,000\;ng/ml\;17\alpha20{\beta}OHP\;or\;5\~1,000\;IU/ml$ HCG for 60 hours, the media with $1\~100\;ng/ml\;17\alpha20{\beta}OHP\;or\;50\~1,000IU/ml$ HCG significantly increased in the rate of ovulation. However supplementation with $1,000\;ng/ml\;17\alpha20{\beta}OHP$or 5 IU/ml HCG did not improve the rate of ovulation compared to controls. This results indicate that supplementation of steroid and HCG except $E_2$ can improve the in vitro maturation and ovulation of oocyte in P. fulvidrac; HCG and $17\alpha20{\beta}OHP$ may be more effective than other steroids on oocyte maturation and ovulation in P. fulvidraco.

• Journal of Aquaculture
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• v.8 no.3
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• pp.171-181
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• 1995

Gonadosomatic index (GSI) of the crucian carp (Carassius auratus) was investigated to clarify annual reproductive cycle from February in 1992 to October in 1994. The values of GSI were high with individual variation from April to July which period was coincided with the breeding season of fish. The GSI was very low in August and September, when follicular atresia developed in the ovaries. GSI value began to increase in October and reached a peak around the following March, which indicated that ovarian follicles may grow during this period. Human chorionic gonadotropin (HCG 10 IU), $17\alpha$, 20\beta-dihydroxyprogesterone\;(1-100{\mu}g/ml)$ and phorbol 12-myristate-13-acetate (TPA, protein kinase C activator, 0.1-10${\mu}M$) induced germinal vesicle breakdown (GVBD), but $4\alpha-phorbol$ 12, 13- didicanoate ($4\alpha-PDD,\;phorbol\; ester\;analogue,\;25{\mu}M$) did not induce germinal vesicle breakdown in the follicular oocytes. Prostaglandin $F_{2\alpha}$ $(0.1-10 {\mu}g/ml)$ and TPA $(0.1-10 {\mu}M$ induced ovulation of the oocytes, but $4\alpha-PDD$ $(25{\mu}M)$ did not induce ovulation of the follicles. $17\alpha-hydroxyprogesterone$ production was examined from the isolated follicles to investigate the steroid production ability in the crucian carp ovaries. HCG (1 lU, 10 lU) and forskolin (adenylate cyclase activator, 0.1-10 ${\mu}M$) stimulated $17\alpha-hydroxyprogesterone$ production. The time course of HCG (10 lU) and forskolin $(10\;{\mu}M)$ stimulated $17\alpha-hydroxyprogesterone$ production within 3 hours, the elevated levels were maintained during the rest of the culture period. The data indicates that cyclic AMP and protein kinase C may play important roles in the oocyte maturation and ovulation in crucian carp.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.2
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• pp.165-176
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• 1994

This study was carried out to investigate the effect of the timing and dose of human chorionic gonadotropin(hCG) on oocyte recovery, in vitro fertilization, and preimplantation development in superovulation of mouse. F1 hybrid($C57BL{\times}CBA$) mice were obtained and superovulation was induced in female mice by sequential intraperitoneal injection of PMSG and hCG. In the first series of experiments, mice received 5 IU of PMSG given intraperitoneally, and 48 hours later were injected 1 IU, 5 IU, or 10 IU of hCG respectively. In the second series of experiments, mice received 5 IU of PMSG given intraperitoneally and were injected 5IU of hCG 36, 48, or 60 hours later respectively. 1. When the mice received 5 IU of PMSG given intraperitoneally and 48 hours later were injected 1 ItT, 5 IU, or 10 IU of hCG respectively, there were no differences in the total number of the oocytes obtained from the three experimental groups. When the cultures were examined 48 hrs after the termination of insemination the proportion of unfragmented oocytes which had developed over two-cell stage was observer to be lowest in 10 IU hCG group. When the cultrues were examined 120 hour after termination of insemination the proportion of embryos which had developed to the blastocyst stage was observed to be significantly higher in 10IU hCG group than 5IU hCG group(p<0.05), but there was no difference between 10 IU hCG group and 1IU hCG group. 2. When the mice received 5 IU of PMSG and were injected 5 IU of hCG 36, 48, or 60 hours later respectively, there were no differences in the total number of oocytes obtained from the three experimental groups. When cultures were examined 48 hour after the termination of insemination the proportion of unfragmented oocytes which had developed over two-cell stage was observed to be significantly lower in 36 hour interval group than 48 hour interval and 60 hour interval group(p<0.05). When the cultures were examined 120 hour after termination of insemination the proportion of embryos which had developed to the blastocyst stage was found to be higher in 60 hour interval group than 36 interval or 48 hour interval group (P<0.05), and the proportion of hatching blastocyst was found to be higher in 60 hour interval group as well. In this study, it was concluded that the administration of adequate dose of hCG, and long (60 hour) PMSG-hCG interval were necessary in superovulation of mice($C57BL{\times}CBA$) in order to get a large number of oocytes which had an early oocytes which had an early embryonic developmental capability when fertilized in vitro, and especially it had better have been avoided to administer a large dose of hCG.

• Clinical and Experimental Reproductive Medicine
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• v.19 no.1
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• pp.41-48
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• 1992

Serum level of ${\beta}$ subunit of human chorionic gonadotropin (${\beta}-hCG$) was studied to evaluate its predictability of pregnancy outcome in 98 in vitro fertilization and embryo transfer(IVF-ET) patients using gonadotropin-releasing hormone(GnRH) agonist. Serial serum ${\beta}-hCG$ levels were established for 42 singleton pregnancies, 20 normal multiple pregnancies, 18 preclinical abortions, 14 clinical abortions and 4 ectopic pregnancies. In comparison to normal singleton pregnancies, multiple pregnancies showed significantly higher ${\beta}-hCG$ levels on the post-ET day 10 to 13 and day 24 to 25. Clinical abortions did not show significantly lower ${\beta}-hCG$ levels in early pregnancy except the post-ET day 16-17, but showed significantly lower ${\beta}-hCG$ levels from the post-ET day 22, compared with singleton pregnancies. Preclinical abortions showed significantly lower ${\beta}-hCG$ levels than those of singleton pregnancies. Ectopic pregnancies showed lower ${\beta}-hCG$ levels than those of singleton pregnancies without statistical significance. In conclusion, determination of serum ${\beta}-hCG$ level in early pregnancy is a useful tool for the prediction of preclinical abortions and multiple pregnancies and serial measurement of serum ${\beta}-hCG$ levels will be helpful in predicting clinical abortion.

• Korean Journal of Veterinary Research
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• v.29 no.3
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• pp.373-381
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• 1989

The aim of the present study was to test the efficiency of estrous induction in the premature, metestrous and anestrous bitches. The estrus was induced with prostaglandin $F_{2{\alpha}}$, estradiol-$17{\beta}$, pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin(HCG) in the treatment A, and with PMSG and HCG in the treatment B. Day 0 was the first day of estrone injection in the treatment A and the day of PMSG injection in the treatment B. Twenty three of the twenty six bitches were laparotomized under general anesthesia between 11 and 18 days after onset of behavioral estrus, whereas three bitches were not laparotomized and remained until parturition. Ovarian responses were evaluated with the total number of corpora lutea or ovulation sites. The uterine horns were flushed with phosphate-buffered saline added heat treated canine serum(10%), the flushing media was collected into watch glass and the ova were examined under stereomicroscope. The results obtained were as follows: 1. Standing estrus was observed on the day $17.7{\pm}1.5$ after injection of estrone in the treament A, but ovarian responses were not detectable. 2. Standing estrus was observed on the day $12.2{\pm}0.2$ after injection of PMSG in the treament Band 14 of 17 bitches showed ovarian responses. Ova were recovered in 9 of the 14 bitches. 3. Ovarian responses were observed in one of the three premature bitches. two of the three metestrous bitches and all of the 11 anestrous bitches. The average number of the ova collected from 9 bitchs were $12.2{\pm}1.4$. 4. Three bitches in the treament B exhibited behavioural estrus and all of them were mated with fertile male dog, resulting the pregnancy in only one bitch. The pregnant bitch gave the birth of two pups.

• Clinical and Experimental Reproductive Medicine
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• v.42 no.4
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• pp.149-155
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• 2015

Objective: The goal of this study was to investigate the relationship between serum progesterone (P4) levels on the day of human chorionic gonadotropin (hCG) administration and the pregnancy rate among women undergoing controlled ovarian stimulation for in vitro fertilization (IVF) or intracytoplasmic sperm injection-embryo transfer (ICSI-ET) using a flexible antagonist protocol. Methods: This prospective study included 200 IVF and ICSI-ET cycles in which a flexible antagonist protocol was used. The patients were divided into five distinct groups according to their serum P4 levels at the time of hCG administration (0.80, 0.85, 0.90, 0.95, and 1.00 ng/mL). The clinical pregnancy rate (CPR) was calculated for each P4 interval. Statistically significant differences were observed at a serum P4 level of 0.9 ng/mL. These data suggest that a serum P4 concentration of 0.9 ng/mL may represent the optimal threshold level for defining premature luteinization (PL) based on the presence of a significant negative impact on the CPR. Results: The CPR for each round of ET was significantly lower in the PL group defined using this threshold (25.8% vs. 41.8%; p=0.019), and the number of oocytes retrieved was significantly higher than in the non-PL group ($17.3{\pm}7.2$ vs. $11.0{\pm}7.2$; p=0.001). Elevated serum P4 levels on the day of hCG administration were associated with a reduced CPR, despite the retrieval of many oocytes. Conclusion: Measuring serum P4 values at the time of hCG administration is necessary in order to determine the optimal strategy for embryo transfer.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.1
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• pp.55-63
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• 2001

Objectives: This study was carried out to evaluate the effects of embryonic stage, cryoprotectant, and freezing-thawing method on the rates of survival and development of the cryopreserved mouse early embryo and finally to establish the cryopreservation method of surplus embryos obtained during assisted reproductive technology (ART). Materials and Methods: Two to eight cell embryos were obtained from oviducts of mated $F_1$ hybrid female mice superovulated by pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Two-step 1,2-propanediol (PROH), dimethylsulfoxide (DMSO) and 4-step PROH DMSO were used as cryoprotectant and dehydration and rehydration method of embryos, and slow-cooling or rapid-cooling method was used as frozen program. The survival rates of embryos were measured after thawing and rehydration, and the developmental rates of embryos were compared and observed during culturing embryos for 24, 48, 72, 96 hrs. Results: As for the survival and development rates of embryos according to embryonic stage, the survival rate of 2 cell stage in PROH and DMSO was significantly higher than 4-8 cell (64.5% versus 62.1 %,79.7% versus 73.2%) (p<0.01, p<0.01), but the development rates of 4-8 cell embryos in PROH and DMSO were significantly higher than 2 cell embryos for whole culture period (p<0.01) and the development rates of 4-8 cell embryos in PROH were significantly higher than 2 cell embryos in DMSO (p<0.01). As for the survival and development rates of embryos according to cryoprotectant, the survival rate of 2 cell embryo in DMSO was significantly higher than that in PROH (74.4% versus 64.5%) (p<0.01), whereas the development rate of embryos was not differ till 24 hrs. The developmen1 rate from morular to hatching blastocyst, however, was significantly higher in PROH than in DMSO during 48 hr (p<0.01). The survival rate of 4-8 cell embryo was 62.1% in PROH and 73.2% in DMSO. The development rates of embryo in PROH were significantly higher for whole culture periods (p<0.01, 0.05). In respect to the effect of freezing and thawing program on the survival and development rates of embryos, method of slow cooling and rapid thawing was more effective than that of rapid cooling and rapid thawing. Conclusions: The survival rate of embryo in 2 cell stage was higher than in 4-8 cell stage, and PROH appears more effective cryoprotectant than DMSO because PROH showed better development rates of embryos in 2 and 4-8 cell stage. Moreover, slow cooling and rapid thawing method was considered as the best cryopreservation program.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.334-339
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• 2007

Reactive oxygen species (ROS) generate during electrical activation of oocytes which has detrimental effects on embryo survival when overwhelmed. The present study was designed to investigate the ability of L-ascorbic acid, a novel water soluble antioxidant, to reduce the ROS level in developing embryos and their subsequent effects on embryo development in vitro. The compact cumulus oocyte complexes (COCs) were cultured in tissue culture medium (TCM)-199 supplemented with 10 ng/ml epidermal growth factor, 4 IU/ml pregnant mare serum gonadotropin (PMSG), and human chorionic gonadotropin (hCG) and 10% (v/v) porcine follicular fluid (pFF) for 44 h. After maturation culture, the denuded oocytes were activated with a single DC pulse of 2.0 kV/cm in 0.3 M mannitol solution containing 0.5 mM of HEPES, 0.1 mM of $CaCl_2$ and 0.1 mM of $MgCl_2$ for $30{\mu}s$ using a BTX Electro-cell Manipulator. The activated oocytes were cultured in modified North Carolina State University-23 (mNSCU-23) medium for 168 h. The level of $H_2O_2$ in each embryo was measured by the dichlorohydrofluorescein diacetate (DCHFDA) method at 48 h after activation. The blastocyst formation rate was significantly higher when culture medium was supplemented with 50 and $100{\mu}M$ L-ascorbic acid (31.2 and 38.7%, respectively) compared to non-supplemented (16.1%) group. Accordingly, significantly more cells in blastocyst were found for 50 and $100{\mu}M$ L-ascorbic acid (50.0 and 56.4, respectively) compared to 0 and $200{\mu}M$ L-ascorbic acid (36.5 and 39.8, respectively). L-ascorbic acid reduces the $H_2O_2$ level in developing embryos in a dose-dependant manner. The $H_2O_2$ level (pixels/ embryos) was 191.5, 141.0, 124.0 and 163.3 for 0, 50, 100 and $200{\mu}M$ L-ascorbic acid, respectively. So, we recommend to supplement 50 or $100{\mu}M$ L-ascorbic acid in porcine in vitro culture medium.