Cryopreservation has been applied successfully in many mammalian species. Nevertheless, pig embryos, because of their greater susceptibility to cryoinjuries, have shown a reduced developmental competence. The aim of this study was to evaluate the survival status of vitrified-warmed porcine embryos. Forced blastocoele collapse (FBC) and non-FBC blastocysts are vitrified and concomitantly cultured in culture media which were supplemented with/without fetal bovine serum (FBS). Porcine vitrified-warmed embryos were examined in four different methods: group A, non- FBC without FBS; group B, non-FBC with FBS; group C, FBC without FBS; group D, FBC with FBS. After culture, differences in survival rates of blastocysts derived from vitrified-warmed porcine embryos were found in group A∼D (39.5 (A) vs 52.5 (B) and 54.8 (C) vs 66.7% (D), respectively, p<0.05). Reactive oxygen species (ROS) level of survived blastocysts was lower in group D than that of another groups (p<0.05). Moreover, total cell number of survived blastocysts was higher in group D than that of other groups (p<0.05). Otherwise, group D showed significantly lower number of apoptotic cells than other groups (2.0±1.5 vs 3.2±2.1, 2.8±1.9, and 2.7±1.6, respectively, p<0.05). Taken together, these results showed that FBS/FBC improves the developmental competence of vitrified porcine embryos by modulating intracellular levels of ROS and the apoptotic index during the vitrification/warming procedure. Therefore, we suggest that FBS and FBC are effective treatment techniques during the vitrification/warming procedures of porcine blastocysts.

Cows may suffer impaired ovarian function, often accompanied by reduced conception rates and increased embryonic loss. Cystic ovarian disease (COD) is one of the most frequently diagnosed gynecological findings in dairy cattle. It causes temporary infertility and is likely to affect reproduction as well as production parameters in cattle. Therefore, the purpose of this study was to determine the expression patterns of apoptosis (Bcl-2, Bax), implantation (E-cadherin) and immune related proteins (TNF-α, IL-10) in uterine endometrium of Hanwoo (Korean native cattle) with ovarian cyst and normal ovarian follicles. In the Western blot analysis, the expression of anti-apoptotic Bcl-2 protein was significantly higher in endometrium with normal ovarian follicles, whereas expression of pro-apoptotic Bax protein was significantly lower. Also, the expressions of E-cadherin and TNF-α proteins were significantly higher in uterine endometrium with normal ovarian follicles. On the other hand, the expression of IL-10 protein was significantly lower in uterine endometrium with normal ovarian follicles. Taken together, our results provided that the expressions of apoptosis, adhesion and immune related proteins in uterine endometrium with ovarian cyst were showed the aberrant patterns, and we suggest that different expression changes of these proteins may be affect to pregnancy ability of cattle.

Humulus japonicus is an ornamental plant in the Cannabaceae family. Although the mode of action of Humulus japonicus is not fully understood, a strong relationship was observed between anti-inflammatory and anticancer in some types of cells. Recent studies also have shown that Humulus japonicus possesses anti-inflammatory activities and may significantly improve antioxidant potential in Raw 264.7 macrophage cells. Thus, the aim of this study was eva-luated the effect of Humulus japonicus extract on sperm motility and subsequent preimplantation developmental com-petence of the bovine embryos. After in vitro maturation, the oocytes with sperms were exposed in in vitro fertilization (IVF) medium supplemented with Humulus japonicus extract (0.01, 0.05, 0.1 μg/mL, respectively) for 1 day. In our results, exposure of IVF medium to Humulus japonicus extract did not affect sperm motility and percentage of pene-trated oocytes but ROS intensity was significantly decreased by 0.01 μg/mL compared with other groups (p< 0.05). Moreover, treatment with 0.01 μg/mL of Humulus japonicus extract was higher the frequency of blastocyst formation than the any other groups (p<0.05). Otherwise, treatment with 0.01 μg/mL of Humulus japonicus extract not increased the total cell number but reduced apoptotic-positive nuclei number. In conclusion, our results indicate that supple-mentation of Humulus japonicus extract in IVF medium may have important implications for improving early embryo-nic development in bovine embryos

Cathepsin B is abundantly expressed peptidase of the papain family in the lysosomes, and closely related to the cell degradation system such as apoptosis, necrosis and autophagy. Abnormal degradation of organelles often occurs due to release of cathepsin B into the cytoplasm. Many studies have been reported that relationship between cathepsin B and intracellular mechanisms in various cell types, but porcine embryos has not yet been reported. Therefore, this study evaluated the effect of cathepsin B inhibitor (E-64) on preimplantation developmental competence and quality of porcine embryos focusing on apoptosis and oxidative stress. The expression of cathepsin B mRNA in porcine em-bryos was gradually decreased in inverse proportion to E-64 concentration by using real-time RT-PCR. When putative zygotes were cultured with E-64 for 24 h, the rates of early cleavage and blastocyst development were decreased by increasing E-64 concentration. However, the rate of blastocyst development in 5 μM treated group was similar to the control. On the other hand, both the index of apoptotic and reactive oxygen species (ROS) of blastocysts were sig-nificantly decreased in the 5 μM E-64 treated group compared with control. We also examined the mRNA expression levels of apoptosis related genes in the blastocysts derived from 5 μM E-64 treated and non-treated groups. Expre-ssion of the pro-apoptotic Bax gene was shown to be decreased in the E-64 treated blastocyst group, whereas expre-ssion of the anti-apoptotic Bcl-xL gene was increased. Taken together, these results suggest that proper inhibition of cathepsin B at early development stage embryos improves the quality of blastocysts, which may be related to not only the apoptosis reduction but also the oxidative stress reduction in porcine embryos.

Pyracantha is a genus of thorny evergreen large shrubs in the family of Rosaceae, with common names Firethorn or Pyracantha. It's extract has also been used in cosmetics as a skin-whitening agent and functioning through tyrosinase inhibition. Recent studies have shown that pyracantha extract possesses antioxidant activities and may significantly improve lipoprotein metabolism in rats. Although the mode of action of Pyracantha extract is not fully understood, a strong relationship was observed between antioxidant and apoptosis in some types of cells. Thus, the aim of this study was to evaluated the effect of pyracantha extract on blastocysts formation and their quality of the porcine parthenogenetic embryos. After parthenogenetic activation by chemicals, presumptive porcine parthenogenetic embryos were cultured in PZM-3 medium supplemented with extracts of pyracantha leaf, stalk and root for 6 day (1, 5 and 10 μg/ml, respectively). In our results, the frequency of blastocyst formation in pyracantha root extract (5 μg/ml) treated group had increased that of other groups. Furthermore, blastocysts derived from pyracantha root extract (5 μg/ml) treated group had increased the total cell numbers and reduced apoptotic index. Blastocyst development was significantly improved in the pyracantha root extract (5 μg/ml) treated group when compared with the H2O2 treated group (p<0.05). Subsequent evaluation of the intracellular levels of ROS in pyracantha root extract (5 μg/ml) treated groups under H2O2 induced oxidative stress were decreased (p<0.05). In conclusion, our results indicate that treatment of pyracantha root extract may improve in vitro development of porcine parthenogenetic embryos through its antioxidative and antiapoptotic effects.

The key regulators of apoptosis are the interacting protein of the Bcl-2 family. Bcl-2, an important member of this family, blocks cytochrome C release by sequestering pro-apoptotic BH3-only proteins such as Bid, Bad, Bax and Bim. The pro-survival family members (Bcl-2, Bcl-XL, Bcl-W) are critical for cell survival, since loss of any of them causes cell death in certain cell type. However, its role during early porcine embryonic development is not sufficient. In this study, we traced the effects of Bcl-2 inhibitor, ABT-737, on early porcine embryonic development. We also investigated several indicators of developmental potential, including gene expression (apoptosis-related genes) and apoptosis, which are affected by ABT-737. Porcine embryos were cultured in the PZM-3 medium with or without ABT-737 for 6 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without ABT-737 (14.7±3.0 vs 30.3±4.8%, p<0.05). TUNEL assay showed that the number of containing fragmented DNA at the blastocyst stage increased in the ABT-737 treated group compared with control (4.7 vs 3.7, p<0.05). The mRNA expression of the pro-apoptotic gene Bax increased in ABT-737 treated group (p<0.05), whereas expressions of the anti-apoptotic Bcl-2 family members (Bcl-2, Bcl-XL, Bcl-W) decreased (p<0.05). Also, expressions of the ER stress indicator genes (GRP78, XBP-1 and sXBP-1) increased in ABT-737 treated group (p<0.05). In conclusion, Bcl-2 is closely associated with of apoptosis- and ER stress-related genes expressions and developmental potential in pig embryos.

Cathepsin B, a lysosomal cystein protease that plays an important role in the degradation of intracellular proteins in lysosomes, is detected in a wide variety of cells including bovine oocytes and embryos. Although the mode of action of cathepsin B is not fully understood, a strong relationship was observed between cathepsin B and apoptosis in many types of cells. Cathepsin B was found to induce the apoptotic pathway through activating initiator caspases rather than executioner caspases. Thus, the aim of this study was evaluated the effect of capthesin B inhibitor, E-64, on blastocyst developmental competence and subsequent preimplantation quality of the IVF and SCNT bovine embryos. After IVF and SCNT procedures, presumptive bovine embryos were cultured in CR1aa medium supplemented with E-64 for 24 h. Then, samples were additionally cultured in CR1aa medium without E-64 for 5 days. In our results, the frequency of blastocyst formation was higher when treated with E-64 compared with the control group (p<0.05). Furthermore, the blastocyst cell number was enhanced and apoptosis reduced (TUNELpositive nuclei number) by E-64 treatment in both IVF and SCNT bovine embryos (p<0.05). In the real-time quantitative RT-PCR, the expression of anti-apoptotic Bcl-xL gene was shown to be increased in the blastocyst stage, whereas expression of proapoptotic Bax was decreased. In conclusion, our results indicate that E-64 improves the developmental competence and embryonic qualities of bovine IVF and SCNT embryos by modulating cathepsin B induced apoptosis during the preimplantation stage.

The objective of this study was to examine the effect of thymidine treatment during in vitro maturation (IVM) of porcine follicular oocytes on blastocyst development. Porcine oocytes were treated with thymidine (10 mM, 20 mM and 30 mM) for 2 or 6 hr in the preiods of IVM I and/or II. The survival rates of the blastocysts in the 6 hr treatment groups of 10 mM and 20 mM during IVM I period were significantly higher than those of control group (p<0.05). However, the survival rate of the blastocysts in the 2 hr treatment group of 20 mM during IVM II period was significantly higher than control group (p<0.05). Furthermore, the survival rate of the blastocysts in the 6 hr treatment group of 30 mM during IVM II period was significantly lower than control group (p<0.05). Consistent with the previous result, blastocyst development of both IVM I and II treatment group was also showed as similar pattern. Total and apoptotic cell numbers of blastocysts derived from thymidine treated porcine oocytes were examined by using Tunel assay. The results showed that there was no significant differences in total cell number of blastocysts between thymidine treated and untreated groups. However, apoptosis-positive cells in the thymidine treated group (6 hr IVM I) were significantly lower than those of other groups (p<0.05). Taken together, these results indicate that high quality oocytes were selected by DNA synthesis mechanism according to high concentration thymidine treatment during porcine oocyte maturation. Therefore, we concluded that presumptive selected oocytes by thymidine treatment during maturation periods improved the further embryo development and embryonic quality of IVF embryos by decreasing the incidence of apoptosis in preimplantation porcine embryos.

The experimental manipulation of protooncogenes and their gene products is a valuable research tool for the study of human neoplasia. In this study, the recently identified human cervical cancer protooncogene (HccR-2) was expressed in transgenic mice under the control of the tetracycline regulatory system. The phenotype observed was similar in many respects to human chronic neutrophilic leukemia (CNL). Thus, the HccR-2 transgenic mouse model is important not only for investigating the biological properties of the HccR-2 protooncogene in vivo, but also for analyzing the mechanisms involved in the progression of CNL.

Freezing of bovine blastocysts has been proposed as a tool to improve the feasibility of cattle production by using embryo transfer technique. However, the low efficiency of frozen-thawed embryos survival and further development is a crucial problem. Thus, we examined the effect of artificial shrinkage before vitrification of bovine expanded, hatched and SCNT embryos on the survival rate, apoptosis index and further development after thawing. Expanded, hatched and SCNT embryos were vitrified after artificial shrinkage, which was performed by puncturing the blastocoele with a pulled pasteur pipet. Artificial shrinkage of the blastocyst was achieved after pushing a pulled pasteur pipet into the blastocoele cavity until it contracted. The shrunken and not shrunken embryos were exposed to cryoprotectant solution in 7.5% ethylene glycol-7.5% DMSOPBS with 20% FBS for 5 min. They were placed in a small volume of vitrification solution (15% ethylene glycol+15% DMSO+PBS+20% FBS+0.5 M sucrose) and plunged into liquid nitrogen on a cryotop. Then, after thawing, cryoprotectant was diluted in 1.0 M, 0.5 M, 0.25 M, and 0 M sucrose for 1, 3, 5, and 5 min. Under the optimal conditions, overall efficiency of the survival rate of bovine expanded, hatched, SCNT embryos in artificial shrinkage groups was higher compared with non-artificial shrinkage groups (p< 0.05). Especially, the numbers of TUNEL-positive nuclei in artificial shrinkage groups were significantly reduced than those of non-artificial shrinkage groups among frozen-thawed expanded, hatched, and SCNT blastocysts (p< 0.05). Our results showed that survival rates in cryopreserved expanded, hatched, SCNT embryos could be improved by reducing the fluid content. Therefore, we suggest that artificial shrinkage method is a effective pretreatment technique for the cryotop vitrification of expanded, hatched, SCNT bovine blastocysts.

Heat shock protein 90 (Hsp90) is ATPase-directed molecular chaperon and affects survival of several cells. In our previous study, inhibitory effect of Hsp90 by inducing cell cycle arrest and apoptosis in the pig embryonic and primary cells was reported. However, its role during early bovine embryonic development is not sufficient. In this study, we traced the effects of Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), on early bovine embryonic development. We also investigated several indicators of developmental potential, including structural integrity, gene expression (apoptosis-related genes), and apoptosis, which are affected by 17-AAG. Bovine embryos were cultured in the CR1-aa medium with or without 17-AAG for 7 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without 17-AAG (33.1±9.6 vs 21.7± 8.3%). The structural integrity of the blastocysts was examined by differential staining. Blastocysts from the dbcAMP- treated group had higher numbers of ICM, TE, and total cells than those from the untreated group. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 17-AAG treated group compared with control (11.2 vs 3.9, respectively). Blastocysts that developed in the 17-AAG treated group had low structural integrity and high apoptotic nuclei than those of the untreated control, resulting in decrease the embryonic qualities of preimplantation bovine blastocysts. The m-RNA expression of the pro-apoptotic gene (Bax) increased in 17-AAG treated group, whereas expression of the antiapoptotic gene (Bcl-XL) decreased. In conclusion, Hsp90 also appears to play a direct role in bovine early embryo developmental competence including structural integrity of blastocysts. Also, these results indicate that Hsp90 is closely associated with apoptosis-related genes expression in developing bovine embryos.

Autophagy is a process of intracellular bulk protein degradation, in which the accumulated proteins and cytoplasmic organelles are degraded. It plays important roles in cellular homeostasis, apoptosis, and development, but its role during early embryo development remains contentious. Therefore, in the present study, we investigated the effects of 3-methyladenine (3-MA) on early embryonic development in pigs. we also investigated several indicators of developmental potential, including mitochondrial distribution, genes expressions (autophagy-, apoptosis- related genes), apoptosis and ER-stress, which are affected by 3-MA. After in vitro maturation and fertilization, presumptive pig embryos were cultured in PZM-3 medium supplemented with 3-MA for 2 days at 39℃, 5% CO2 in air. Developmental competence to the blastocyst stage in the presence of 3-MA was gradually decreased according to increasing concentration. Thus, all further experiments were performed using 2 mM 3-MA. Blastocysts that developed in the 3-MA treated group decreased LC3-II intensity and expressions of autophagy related genes than those of the untreated control, resulting in down-regulates the autophagy. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 3-MA treated group compared with control (6.0±1.0 vs 3.3±0.6, p<0.05). Also, the expression of the pro-apoptotic gene Bax increased in 3-MA treated group, whereas expression of the anti-apoptotic gene Bcl-XL decreased. Mito Tracker Green FM staining showed that blastocysts derived from the 3-MA treated group had lower mitochondrial integrity than that of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. Then, the expression of the spliced form of pXBP-1 product (pXBP-1s) increased in 3-MA treated group, resulting increase of ERstress. Taken together, these results indicate that inhibition of autophagy by 3-MA is closely associated with apoptosis and ER-stress during preimplantation periods of porcine embryos.

Heat shock protein 90 (Hsp90) is ATPase-directed molecular chaperon and affects survival of cancer cell. Inhibitory effect of Hsp90 by inducing cell cycle arrest and apoptosis in the cancer cell was reported. However, its role during oocyte maturation and early embryo development is very insufficient. In this study, we traced the effects of Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), on meiotic maturation and early embryonic development in pigs. We also investigated several indicators of developmental potential, including structural integrity, gene expression (Hsp90-, cell cycle-, and apoptosis-related genes), and apoptosis, which are affected by 17-AAG. Then, we examined the roles of Hsp90 inhibitor on viability of primary cells in pigs. Porcine oocytes were cultured in the NCSU-23 medium with or without 17-AAG for 44 h. The proportion of GV arrested oocytes was significantly different between the 17-AAG treated and untreated group (78.2 vs 34.8%, p<0.05). After completion of meiotic maturation, the proportion of MII oocytes was lower in the 17-AAG treated group than in the control group (27.9 vs 71.0%, p<0.05). After IVF, the percentage of penetrated oocytes was significantly lower in the 17-AAG treated group (25.2%), resulting in lower normal pronucleus formation (2PN of 14.6%). Therefore, the inhibition of meiotic progression by Hsp90 inhibitor played a critical role in fertilization status. Porcine embryo were cultured in the PZM-3 medium with or without 17-AAG for 6 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without 17-AAG. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 17-AAG treated group compared with control (7.5 vs 4.4, respectively). Blastocysts that developed in the 17-AAG treated group had low structural integrity and high apoptotic nuclei than those of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. The mRNA expressions of cell cycle-related genes were down-regulated in the 17-AAG treated group compared with control. Also, the expression of the pro-apoptotic gene Bax increased in 17-AAG treated group, whereas expression of the anti-apoptotic gene Bcl-XL decreased. However, the expression of ER stress-related genes did not changed by 17-AAG. Cultured pESF cells were treated with or without 17-AAG and used for MTT assay. The results showed that viability of pESF cells were decreased by treatment of 17-AAG (2 μM) for 24 hr. These results indicated that 17-AAG decreased cell proliferation and increased cell death. Expression patterns Hsp90 complex genes (Hsp70 and p23), cell cycle-related genes (cdc2 and cdc25c) and apoptosis-related genes (Bax and Bcl-XL) were significantly changed by using RT-PCR analysis. The spliced form of pXbp-1 product (pXbp-1s) was detected in the tunicamycin (TM) treated cells, but it is not detected in 17-AAG treated cells. In conclusion, Hsp90 appears to play a direct role in porcine early embryo developmental competence including structural integrity of blastocysts. Also, these results indicate that Hsp90 is closely associated with cell cycle- and apoptosis-related genes expression in developing porcine embryos.

인간의 불임을 극복하기 위한 번식공학 기술의 효율성을 증가시키기 위해 성세포의 동결이 널리 수행되고 있으나 동결 기술의 효율성에 있어서 논란의 여지가 있다. 본 연구에서는 체외수정란을 생산하기 위한 난자세포질내 정자미세주입(ICSI) 시술에 사용되는 정자와 이들 기술을 이용 생산한 체외수정란의 동결이 배 발생 및 임신에 미치는 효과를 조사하였다. ICSI방법으로 체외수정란을 생산하는 경우 정자의 동결이 체외수정, 발생 및 임신에 영향을 미치지 않았으며, 특히 동결융해한 사출 및 정소정자에 의한 체외수정율과 발생율 및 임신율도 차이가 없었다. 한편 체외수정란을 동결하는 경우 완만동결과 초자화동결에 의한 체외수정란의 생존율과 임신율은 차이가 없었으나, 동결수정란은 신선수정란에 비하여 임신율이 유의하게 낮았다(p<0.05). 결론적으로 ICSI에 사용되는 정자와 달리 ICSI에 의해 생산된 수정란을 동결하는 경우 임신율을 저하시킬 수 있다.