• 한국수정란이식학회지
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• 제24권4호
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• pp.275-279
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• 2009

The beneficial effect of glycerol as a cryoprotectant, especially for sperm cryopreservation, has been shown in many studies. However, glycerol is toxic to living cells, and boar sperm in particular show greater sensitivity to glycerol than sperm from other domestic animals. Amides have been studied as alternative cryoprotectants for freezing stallion sperm. Sperm frozen in methylformamide or dimethylformamide as cryoprotectants show similar motility when thawed compared with sperm frozen in glycerol. We evaluated the cryoprotective effects of dimethylformamide on boar sperm freezing. To test the effect of amides, the concentration of boar semen was adjusted to $10^9sperm/mL$, and seminal plasma was removed using Hulsen solution. After centrifugation, the pellet was diluted in modified-Modena B extender. Lactose-egg yolk (LEY) extender was used as the cooling extender. The freezing extender was madeed aaddition of the optimal amount of glycerol and amides to LEY-Glycerol-Orvus ES Paste extender, and this extender was used for the second dilution. Diluted sperm were frozen in liquid nitrogen using the 0.5 mL straw method. Sperm frozen in extender with glycerol as a cderol were compared with those frozen in extender including the different amides. Sperm were tested for motility, viability, the sperm chromatin structure assay, and normal apical ridge after thawing. The percent of motile sperm diluted in glycerol was as high as that in the stallion study (61%). Dimethylformamide showed positive effects on sperm quality and was better than glycerol. Methylformamide provided similar sperm quality as glycerol. Therefore, dimethylformamide is useful for reducing cryoinjury in boar sperm and is expected to be useful as an alternative cryoprotectant.

• 대한수의학회지
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• 제33권4호
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• pp.757-762
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• 1993

The ovaries of Korean Native cows or heifers were obtained from an abattoir and kept on 20 to $25^{\circ}C$ and transported to laboratory within 2 hrs. The follicular oocystes were collected from 2~6mm follicles in diameter and classified into 3 grades by the morphology of cumulus cells attached. The oocytes were matured in vitro(IVM) for 24 hrs. in TCM-199 supplemented with $23{\mu}g/ml$ FSH, $10{\mu}g/ml$ LH, $1{\mu}g/ml$ estradio-17 ${\beta}$ and granulosa cells at $39^{\circ}C$ under 5% $CO_2$ in air. They were fertilized in vitro(IVF) by incubation for 12 hrs. of epididymal spermatozoa pretreated with heparin, and then the zygotes were co-cultured in vitro(IVC) with oviductal epithelial cells for 7 to 9 days. Assessment of maturation revealed that 93.0%(147/158) of grade I oocytes had expanded of cumulus cells, which was higher(p<0.05) than the 79.4%(85/107) of grade II oocytes. Compared to epididymal sperm(32.9%), the insemination with frozen and thawed sperm resulted in slightly lower(20.5%), but not significant, development to morulae and blastocysts from grade I oocytes. Co-culture of bovine IVF embryos with oviductal epithelial cells improved the development to transferable embryos significantly(38.1%), compared to co-culture with granulosa cells(20.0%). When VF bovine embryos were vitrified at blastocyst, the post-thaw survival rate was obtained higher resulf for 1 min. equilibration time(82.6%) or 2 min.(73.9%) than 3 min.(18.2%) in EFS solution.

• 한국임상수의학회지
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• 제36권5호
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• pp.259-265
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• 2019

This study was designed to investigate the effects of alpha-glucosyl rutin (G-rutin) and its comparative effects with other antioxidants (glutathione: GSH, catalase: CATA and beta-mercaptoethanol : ${\beta}ME$) on dog sperm freezing. In the first experiment (E1), the spermatozoa were diluted in freezing extender supplemented with 0 (control), 0.001, 0.01, or 0.1% G-rutin and frozen using liquid nitrogen ($LN_2$). The progressive motility, reactive oxygen species (ROS) level and apoptosis of spermatozoa were assessed after sperm thawing at $37^{\circ}C$ for 25 sec. In the second experiment (E2), 0.1% G-rutin group was compared with 10 mM ${\beta}-ME$, $5{\mu}M$ GSH and $50{\mu}M$ CATA groups by assaying progressive motility, viability and gene expression of Bcl-2 and SMCP after sperm freezing and thawing. In E1, 0.1% G-rutin group showed higher (P < 0.05) post-thaw progressive motility and lower (P < 0.05) ROS levels. In E2, the expressions of SMCP in G-rutin group were higher (P < 0.05) than in CATA group while Bcl-2 expression of G-rutin group was higher (P < 0.05) than ${\beta}-ME$ and CATA groups. However, there were no significant differences in progressive motility and viability. Therefore, we suggest that G-rutin can be used as a potentially antioxidative supplement in dog sperm freezing extender on the basis of gene expression related to motility and apoptosis as well as ROS level.

• Clinical and Experimental Reproductive Medicine
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• 제24권2호
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• pp.187-192
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• 1997

The survival rate and motility recovered after cryopreservation of testicular spermatozoa in testicular sperm extraction (TESE)-ICSI program is low. The purpose of this study was to assess the availability and efficiency of mouse empty zona pellucida in cryopreserving human TESE spermatozoa. Mouse empty zonae pellucidae were obtained by extraction of cytoplasm with or without cytochalasin B treatment. Motile sperm from proven-fertile donor and two azoospermic patients after TESE were individually inserted into empty zona pellucida and cryopreserved. Two to five days after cyropreservation, the frozen sperm were thawed and the rates of recovery and motility were observed. The ooplasmic extraction rates of control (N=80) and cytochalasin B treated oocytes (N=80) were 94.0% and 96.2%, respectively (p>0.05). The post-thaw recovery rates of spermatozoa and rates of motility recovery of ejaculate (N=70) and testicular (N=70) sperm were 97.1%, 97.1% and 95.7%, 94.3%, respectively (p>0.05). The results of this study showed that the mouse zone pellucida is useful for cryostorage of single testicular spermatozoa.

• 한국동물생명공학회지
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• 제37권2호
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• pp.113-120
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• 2022

Sperm cryopreservation is a fundamental process for the long-term conservation of livestock genetic resources. Yet, the packaging method has been shown, among other factors, to affect the frozen-thawed (FT) sperm quality. This study aimed to develop a new mini-straw for sperm cryopreservation. In addition, the kinematic patterns, viability, acrosome integrity, and mitochondrial membrane potential (MMP) of boar spermatozoa frozen in the developed 0.25 mL straw, 0.25 mL (minitube, Germany), or 0.5 mL (IMV technologies, France) straws were assessed. Post-thaw kinematic parameters were not different (experiment 1: total motility (33.89%, 32.42%), progressive motility (19.13%, 19.09%), curvilinear velocity (42.32, 42.86), and average path velocity (33.40, 33.62) for minitube and the developed straws, respectively. Further, the viability (38.56%, 34.03%), acrosome integrity (53.38%, 48.88%), MMP (42.32%, 36.71%) of spermatozoa frozen using both straw were not differ statistically (p > 0.05). In experiment two, the quality parameters for semen frozen in the developed straw were compared with the 0.5 mL IMV straw. The total motility (41.26%, 39.1%), progressive motility (24.62%, 23.25%), curvilinear velocity (46.44, 48.25), and average path velocity (37.98, 39.12), respectively, for IMV and the developed straw, did not differ statistically. Additionally, there was no significant difference in the viability (39.60%, 33.17%), acrosome integrity (46.23%, 43.23%), and MMP (39.66, 32.51) for IMV and the developed straw, respectively. These results validate the safety and efficiency of the developed straw and highlight its great potential for clinical application. Moreover, both 0.25 mL and 0.5 mL straws fit the present protocol for cryopreservation of boar spermatozoa.

• Clinical and Experimental Reproductive Medicine
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• 제49권2호
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• pp.117-126
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• 2022

Objective: This study examined whether the addition of triple antioxidants (3A)-10 µM acetyl-L-carnitine, 10 µM N-acetyl-L-cysteine, and 5 µM α-lipoic acid-in freezing-thawing medium during human sperm cryopreservation using the sucrose vitrification (SuV) and liquid nitrogen vapor (Vapor) techniques could improve post-thaw survival of spermatozoa. Methods: We analyzed 30 samples from healthy human sperm donors. Each sample was allocated into one of five groups: fresh control, SuV, SuV+3A, Vapor, and Vapor+3A. The sperm motility, morphology, viability, intracellular and extracellular reactive oxygen species (ROS) levels, and sperm DNA fragmentation (SDF) were evaluated. Results: The cryopreserved spermatozoa had significantly reduced percentages of motility (p<0.05) and viability (p<0.05). Antioxidant supplementation non-significantly improved these parameters (p>0.05). No significant differences were found in sperm morphology between the fresh and frozen-thawed groups (p>0.05). After freezing, the extracellular ROS levels in the frozen-thawed groups were significantly higher (p<0.05) than in the fresh group. However, we did not find any differences in intracellular ROS parameters among these groups (p>0.05). The SDF was higher in the SuV and Vapor groups than in the fresh group, but without statistical significance (p=0.075 and p=0.077, respectively). Conclusion: Cryopreservation had detrimental effects on sperm motility, viability, and extracellular ROS levels, without changing the morphology or intracellular ROS levels. Antioxidant supplementation was slightly effective in preventing SDF in frozen-thawed spermatozoa.

• 한국자원식물학회지
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• 제36권6호
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• pp.571-579
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• 2023

In this study, cryopreservation by droplet-vitrification was applied to pear (Pyrus spp.) germplasm. We focused on the development and assessment of various strategies for the selection of suitable tissue, osmoprotection, and dehydration. We also evaluated post-thaw recovery of cryopreserved explants by droplet-vitrification. Preferentially, we tested the effects of preculture and loading treatments to determine which tissues were more suitable, either the apical shoot tips or the axillary buds. Apical shoot tips showed the better regrowth rate than in vitro axillary buds. The most effective techniques for cryopreservation were as follows. Shoots from in vitro seedlings which had been cultured for about 5-6 weeks were cold-hardened at 4℃ for one week, excised shoot tips were precultured on liquid MS medium including 0.3 M sucrose for 31 hours and 0.7 M sucrose for 17 hours, osmoprotected in loading solution (LS) for 40 min, and then cryoprotected in dehydration solution (PVS3) for 90 min. In addition, we found that regrowth rates of explants on regrowth medium after exposure to liquid nitrogen (LN) were higher than those on MS medium. Results indicated that the highest regrowth percentage was 95.6% for 'Bartlett' cultivar and 68.9% for 'BaeYun No.3' cultivar. Consequently, apical shoot tips of two pear cultivars, 'Bartlett' (P. communis) and 'BaeYun No.3' (P. pyrifolia), were successfully cryopreserved by droplet-vitrification. Results of this study show that the enhanced droplet-vitrification method described in the present study could be used as an effective means for long-term storage of pear genetic resources.

• 한국수정란이식학회지
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• 제18권1호
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• pp.43-50
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• 2003

정자의 동결보존을 위한 새로운 기술개발 목적은 동결과정에서 최소한의 손상으로, 응해 후 최대한 높은 활력도의 정자를 얻는 것이다 정자가 난자와 수정하기 위해서는 적당한 생존성과 운동성을 유지해야 하는데, 가장 일반적인 방법으로는 정자의 진진 운동성과 첨체의 정상 여부 및 형태 검사방법 등이 있다 본 연구는 사람 정액을 동결보존 할 때 semi-programmable freezer를 이용한 완만동결 방법과, 액체질소의 vapor를 이용한 급속동결 방법이 응해 후 정자의 운동양상과 생존율 및 형태에 미치는 영향을 알아보기 위해 실시하였다. 동결-응해 후 정자의 MOT, VCL, VSL, VAP는 각각 급속 동결방법에서 47.40$\pm$20.06%, 38.12$\pm$15.58 $\mu$m/s, 28.19$\pm$14.10 $\mu$m/s, 33.64$\pm$15.15 $\mu$m/s로 완만 동결방법인 43.39$\pm$18.79%, 33.91$\pm$13.50 $\mu$m/s, 19.98$\pm$10.88 $\mu$m/s, 24.60$\pm$11.72 $\mu$m/s보다 유의적으로 높았으나(p<0.05), LIN은 완만동결 방법이 34.64$\pm$11.36으로 급속동결 방법인 28.83$\pm$10.35보다 더 좋은 성적을 나타내었다(p<0.05). 고 활력정자를 나타내는 HYP 역시 급속동결 방법에서 2.77$\pm$2.71%로 완만동결 방법의 1.33$\pm$1.57%보다 유의적으로 높게 나타났다(p<0.05). 그러나 정자의 운동양태를 나타내는 MAD, WOB, DNC, DNM에 있어서는 완만동결 방법이 급속동결 방법에 비해 조금 더 좋은 성적을 보였으나 유의적인 차이는 없었다. 동결-응해 후 정자의 생존율 및 정상형태의 정자는 완만동결 방법이 각각 62$\pm$2.1%, 44$\pm$8.3%, 급속동결 방법은 60$\pm$2.2%, 46$\pm$7.7%로 유의적인 차이가 없이 비슷한 결과를 보였다. 따라서 사람 정액의 동결 보존 시 많은 시간과 고가의 장비가 필요한 완만동결 방법보다는 짧을시간동안 액체 질소만으로 간단히 시행할 수 있는 급속동결 방법이 더 효과적이라고 사료된다.

• 한국산학기술학회논문지
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• 제21권9호
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• pp.251-258
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• 2020

본 연구에서는 동결보존액에 대한 Zardaverine (phosphodiesterase inhibitor) 첨가가 돼지 동결-융해 정자의 운동학적 특성에 미치는 효과를 조사하였다. 돼지정액의 동결보존은 보조 번식기술 및 유전자원 장기보존을 위해 유용하게 이용되는 중요한 기술이다. 하지만 정자세포를 동결-융해하는 과정에서 발생하는 온도충격은 정자의 수정능력을 급격히 저하시킨다. 정액샘플은 성숙한 Duroc종 수퇘지로부터 채취했으며, lactose-egg yolk 동결보존액에 다양한 농도로 Zardaverine (0, 20, 50, 75 및 100 𝜇M)을 첨가하여 정액을 동결하였다. 융해 후 정자세포의 운동학적 특성 분석은 정자운동성자동분석기(CASA; computer-assisted sperm analysis)를 이용하였다. 그 결과, 융해 직후 정자의 운동성(MOT)은 타처리구에 비해 20 𝜇M 처리구에서 가장 높았다(p<0.05). Curvilinear velocity (VCL)은 0 𝜇M 과 20 𝜇M 처리구가 75 𝜇M 처리구를 제외한 다른 처리구들에 비해 유의적으로 높은 값을 보였다(p<0.05). Average path velocity (VAP)는 20 𝜇M 처리구가 100 𝜇M 처리구에 비해 유의적으로 높았으며(p<0.05) Amplitude of head lateral displacement (ALH)는 20 𝜇M 처리구가 50 𝜇M과 100 𝜇M 처리구에 비해 유의적으로 높았다(p<0.05). 이상의 결과를 종합하면, 동결용 보존액에 대한 Zardaverine 첨가가 동결-융해된 돼지 정자의 운동학적 특성에 긍정적인 영향을 미치는 것으로 사료된다.

• 한국수정란이식학회지
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• 제24권3호
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• pp.199-205
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• 2009

This study was carried out to investigate the effective genetic resources preservation system using the frozen boar semen. The porcine oocytes were matured for 44 hours in NCSU-23 medium with or without 10% Porcine Follicle Fluid (PFF), 0.5 ${\mu}g/ml$ porcine FSH, 0.5 ${\mu}g/ml$ equine LH, 1.0 ${\mu}g/ml$ 17 $\beta$-estradiol ($E_2$) and 10 ng/ml Epidermal Growth Factor (EGF) under mineral oil at $38.5^{\circ}C$ in humidified atmosphere of 5% $CO_2$ in air. After 44 h of culture, the oocytes were inseminated with frozen-thawed semen and fresh semen prepared with mTBM medium for 6 h. Later, set of 50 presumptive zygotes were transferred into 4-well dish (500 ${\mu}l$) of IVC medium. for embryos freezing, slow-freezing and vitrification methods were used as a cryopreservation. Differences among treatments were analyzed using General Linear Model Procedure by SAS Package (version 6.12) differences were considered significant when p<0.05. Following IVF and IVC, the rates of cleavage and blastocysts formation were significantly higher (p<0.05) in hormone supplemented group than that of hormone-free group (25.7 vs, 12.1). The development rates to cleavage and blastocysts were significantly higher in PZM-5 group than NCSU-23 group (60.3%, 46.6% vs 27.4%, 11.1%). Further improvement was achieved when PZM-5 was supplemented with FBS. Cleavage rates was significantly higher in fresh semen source group than frozen semen (66.7% vs 43.7%). However in blastocysts rates was similar two groups. Post-thaw survival rates of embryos were 1.2% and 2.2% in slow-frezing and vitrification groups, respectively. The results of our study suggest that it is still possible to improve the culture conditions and boar semen cryopreservation for enhance reproductive technology and animal genetic resources conservation.