Amniotic membrane stem cells are considered as a good alternative to embryonic stem cells, but their use in clinical studies is still not common. Here, exosomes from canine amniotic membrane mesenchymal stem cells (cAmMSCexo) were used for dog sperm cryopreservation. Upon cryopreserved straws using cryoprotectant containing 0, 0.5, 1, or 2 μg/mL of cAmMSC-exo were thawed, motility and membrane integrity were analyzed. However, results showed no significant differences between the groups. We concluded that cAmMSC-exo with lower than 2 µg/mL have no effects on sperm cryopreservation, and further studies to get higher concentrations of cAmMSC-exo should be conducted for clinical application.
The present study was undertaken to evaluate the effect of trisaccharides supplementation in glycerol-free tris (GFT) for the cryopreservation of dog spermatozoa. In the first experiment (E1), dog spermatozoa were resuspended with 50, 75, 100 or 125 mM of raffinose, melezitose or maltotriose and cooled at 4 ℃ for 10 min. To determine the effect of different cooling time, the spermatozoa resuspended with 100 mM of raffinose, melezitose or maltotriose were cooled during 10, 20, 30 or 40 min at 4 ℃ (second experiment; E2). The straws were then aligned horizontally for 10 min on the rack and then plunged into LN2. In the third experiment (E3), to determine the effect of different vapor freezing time, the spermatozoa resuspended with 100 mM raffinose were cooled at 4 ℃ for 20 min and frozen in LN2 for 5, 10, 15 or 20 min and then plunged into LN2. In the fourth experiment (E4), to compare different freezing methods [cooling plus vapor freezing (CV), cooling plus step-down freezing (CS) and direct step-down freezing (SD)], the spermatozoa resuspended with 100 mM raffinose were cooled for 20 min and frozen in LN2 vapor for 5 min in case of CV method. In case of CS method, spermatozoa were cooled for 20 min at 4℃ and then frozen by the step-down freezing method. The straws were then aligned horizontally at 18, 15, 5, and 2 cm respectively from the surface of LN2 for 1, 1, 1.4, and 5 min, respectively in an L shaped straw holder and then plunged into LN2. For SD method, the straws were directly aligned horizontally at the same levels as CS from the surface of LN2 for 1, 1, 1.9, and 5 min, respectively and then plunged into LN2. After thawing at 37℃ for 25 sec, the spermatozoa were then incubated for 30 min in the freezing extender (E1) or in the 50 mM sucrose supplemented GFT (E2, E3, and E4) at 24℃. Following post-thaw incubation, sperm progressive motility and viability were assessed in E1, E2, E3, and E4. In addition, acrosome integrity, and gene expression related to apoptosis (BAX, BCL2, and Caspase10) and sperm motility (SMCP) were evaluated in E4. The results demonstrated that, in E1, using 75 mM trisaccharides resulted in significantly (p<0.05) higher sperm motility in all sugar groups. Using 100 mM melezitose significantly (p<0.05) improved the post-thaw viability than the 100 mM raffinose. The viability in 100 mM maltotriose was similar with 100 mM raffinose and melezitose group. In E2, the different cooling time has no significant effect on post-thaw sperm progressive motility in all the sugar types. In addition, the viability was variable among the different groups. In E3, liquid nitrogen vapor freezing for 5 min resulted in improved motility and viability. The sperm progressive motility was significantly (p<0.05) higher in CV and SD group compared to CS group and the sperm viability was significantly (p<0.05) higher in CV group compared to the other groups in E4. However, the acrosomal integrity of spermatozoa in the group CV was significantly (p<0.05) higher than the group CS and SD. In addition, the expression of SMCP gene was significantly (p<0.05) higher in the CV group than the CS group. In contrast, the expression of Caspase10 significantly (p<0.05) lower in the group CV and SD than the group CS. Furthermore, the ratio of gene expression of BAX and BCL2 was significantly (p<0.05) lower in the group CV than the group CS. Therefore, cryopreservation of dog spermatozoa in 100 mM of raffinose supplemented GFT cooled for 20 min and vapor freezing for 5 min provides better progressive sperm motility, viability, and acrosome integrity with higher expression of SMCP gene and lower expression of caspase10 and BAX/BCL2 ratio following post-thaw incubation in 50 mM sucrose supplemented GFT for 30 min at 24℃.
The present study was aimed to determine the effects of green tea extract (GTE) and beta-mercaptoethanol (β-ME) supplementation in boar sperm freezing extender on in vitro fertilization (IVF) and reactive oxygen species (ROS) and glutathione (GSH) levels of presumptive zygotes (PZs). Experimental groups were allocated into lactose egg yolk (LEY) without antioxidant (control), GTE (1,000 mg/l in LEY) and β-ME (50 μM in LEY). In freezing, spermatozoa extended with LEY were cooled to 5°C for 3 h and then kept at 5°C for 30 min following dilution with LEY containing 9% glycerol and 1.5% Equex STM. The final sperm concentration was 1 × 108/ml. Spermatozoa were loaded into straws and frozen in nitrogen vapor for 20 min. For IVF, oocytes were matured in NCSU-23 medium and co-cultured with spermatozoa following thawing at 37°C for 25 sec. At 12 h following IVF, IVF parameters (sperm penetration and monospermy) were evaluated. In addition, GSH and ROS levels of PZs were determined by Cell Tracker Blue CMF2HC and DCHFDA, respectively. IVF parameters did not show any significant difference among the experimental groups. GSH and ROS levels of PZs were not significantly different between groups. In conclusion, antioxidant supplementation in boar sperm freezing could not influence IVF parameters, ROS and GSH levels of PZs.
In this experiment, we determined the effect of curcumin supplementation in freezing buffer for miniature pig sperm cryopreservation. Each ejaculate was diluted with modified Modena B extender and mixed with lactose-egg yolk (LEY extender, 80% v/v lactose solution [310 mM], 20% v/v egg yolk, and100 μg/mL kanamycin sulfate) and LEY-glycerol Orvus ES Paste (LEYGO, 89.5% v/v LEY, 5% v/v glycerol, 1.5% v/v Orvus ES Paste), 100 mM trehalose supplemented with 0, 10, 50, 100, and 500 μM of curcumin from turmeric, respectively. Following equilibration, the 0.5 mL French straws were frozen and plunged into LN2 tank for 7 days at least. Sperm parameter and oxidative byproducts were determined by the computer assisted sperm motility analysis (CASA) and fluorescence-activated cell sorting (FACS) as compared with each groups.Supplementation of curcumin had no effect on sperm motility, progressive motility and curvilinear velocity. However, average-path velocity and straight-line velocity were significantly higher in 10 μM curcumin group (100.9±8.8 μm/s, 61.7±2.9 μm/s, respectively) than control group (77.8±3.9 μm/s, 46.4±3.0 μm/s, respectively) (p < 0.05). In addition, the level of the O2 radical and H2O2 were comparatively decreased in curcumin groups by evaluation of ethidium and DCF fluorescence. According to the results, curcumin can improve sperm kinetic variables and alleviate ROS induced cryoinjury to pig sperm.
The present study was aimed to determine the effect of green tea extract (GTE) and beta-mercaptoethanol (β-ME) supplementation in boar sperm freezing extender on sperm motility, viability and reactive oxygen species (ROS) level. Experimental groups were allocated into Lactose-egg yolk (LEY) without antioxidant (control), GTE (1,000 mg/L GTE in LEY) and β-ME (50 μM β-ME in LEY). Spermatozoa extended with LEY were cooled to 5°C for 3 h and then kept at 5°C for 30 min following dilution with LEY containing 9% glycerol and 1.5% Equex STM (final sperm concentration: 1 × 108/mL). Spermatozoa were loaded into straws and frozen in nitrogen vapor for 20 min. Following thawing at 37°C for 25 sec, sperm viability and ROS level were measured using fluorescent double stain Fertility® and cytometry, respectively. Motility and viability of GTE supplemented-group were higher than those of control and β-ME without significance. ROS level in GTE group showed significantly lower than control (P < 0.05). In conclusion, GTE supplementation in boar sperm freezing extender can reduce ROS generation during freezing.
The recovery of epididymal sperm in animals is considered as one of the important tools to preserve high value or endangered species. However, there are no appropriate castrating indicators such as months of age in bull, sperm morphology, and motility, particularly in young Korean native bull (Hanwoo). Therefore, this study aimed to investigate sperm number, morphology, and motility of sperm in the epididymis tail of young Hanwoo bulls at 8 and 15 months of age. After castration, epididymal tails were collected and minced with blades to recover sperm. In experiments 1 and 2, sperm number, morphology, and motility were examined. Total number of sperm and percentage of normal sperm from bulls at 8 months of age was lower than that of bulls at 15 months of age after collection (P<0.05). Percentage of abnormal head, tail, proximal cytoplasmic droplet, dead and damaged acrosome of sperm from bulls at 8 months of age were higher than those of bulls at 15 months of age (P<0.05). In experiment 3, sperm motility from bulls at 8 and 15 months of age were examined before freezing and after thawing. Frozen-thawed sperm at 8 months of age showed low total motility and motile sperm with ≥ 25 μm/sec compared to those at 15 months of age and commercially-used sperm (P<0.05). In conclusion, sperm derived from the epididymal tail of bulls at 8 months of age showed high abnormal morphology and poor motility, which are not adequate for AI and IVF. On the other hand, sperm derived from the epididymal tail of bulls at 15 months of age showed high normal morphology and motility.
The boar sperm has more lipid droplets and specialty of seminal plasma compared with other species, causing difficulties of freezing sperm and decreases for the utilization of frozen semen into the artificial insemination. However, several studies reported significant results for the recovery of sperm motility and reproductive by addition of cryoprotectants and seminal plasma after thawing. This study was designed to investigate the effects of supplementation of trehalose or glycerol in the LEY (lactose and egg yolk in BTS) solution for the conventional freezing and vitrification process. Two boars aged 16 months were used to collect semen for 2 times in a week. The samples were allotted to 3 freezing solutions (LEY + glycerol 10.5% + OEP 1.5%, LEY + trehalose 1M + OEP 1.5%, and sucrose 1.5M + trehalose 1 M + OEP 1.5%) after centrifugation at 800 g for 10 minutes. Semen was equilibrated in freezing solutions for 10 minutes and injected into plastic straws with 2∼3 air bubbles to minimize freezing damages. Vitrification was performed to locate sperm in 5 cm above LN2 for 5 minutes, and the conventional freezing was conducted with an automatic freezer. Motility and survival rates were measured by CASA (Computer assisted sperm an alyzing system) and FITC (Fluorescein isothiocyanate), respectively after thawing semen at 50℃ for 12 seconds. The results were analyzed by ANOVA with STATVIEW statistical program. The vitrificatioin solution (LEY + 10.5% glycerol + 1.5% OEP) presented higher motility (20.9%) than other solutions while the solution (LEY + 1M trehalose + 1.5% OEP) showed the lowest (motility : 5.2%). However, survival rates of vitrified sperms detected by FITC showed 1~4% live sperms in almost of dead sperms at all vitrification solutions’ groups, but survival rate of freezing solution of LEY + 1M trehalose + 1.5% OEP LEY and LEY + 10.5% glycerol + 1.5% OEP were showed 49%, and 79%, respectively. There were differences (P<0.05) survival rate of conventional freezing in LEY + 10.5% glycerol + 1.5% OEP and LEY + 1M trehalose + 1.5% OEP and the remaining showed no differences. The results suggested that vitrified boar semen was not enough to be utilized for the artificial insemination, but it showed possibility to utilize for ICSI and conventional freezing with glycerol would be useful method for artificial insemination in pig while we choose the outstanding semen against tolerance to freezing damages.
Artificial insemination (AI) has been performed widely in swine industry using fresh liquid sperm instead of frozen type of sperm. However fresh sperm are not able to preserve more than three days with optimal motility and other sperm parameters for the successful fertilization, since in vitro stored sperm has an oxidative stress that resulted increase of abnormality and acrosome reation. To overcome these major problems, novel preservative formulation is needed to neutralize the oxidative stress and to provide suitable physiological environment for sperm in in vitro. In this study, naturally derived substances such as Poncirus trifoliate (Trifoliate orange), Garcinia mangostana (Mangosteen), pig placenta and testis extracts were tested as sperm preservative agents. Placenta extracts (PE), trifoliate orange extracts (TOE), testes extracts (TE) and mangosteen extracts (ME) were applied to analyze specific parameters for sperm motion characteristics individually and combinatorial. Each individual extract treatment can accelerate the sperm motility but noticeably TOE, TE and ME treatments exhibited the considerable and significant preservation of sperm motility. PE, TE and ME showed a significant (p<0.05) increase in ALH after one week. Further we evaluated the five different combinations of these extracts on sperm motility and its motion characteristics. Surprisingly even after one week ME, TOE and TE combination significantly preserved the sperm motility about 75%. It is noteworthy that unlike individual extract treatment, combination of ME, TOE and TE simultaneously protect the sperm motility and its motion characteristics. Taken together these data conclude that addition of ME, TOE and TE can be effective for preservation of pig sperm.
The objective of this study was to assess the effect on post-thawed sperm motility, viability and acrosome integrity of boar semen frozen in the freezing extender with chicken or duck egg yolks. The Sperm rich fraction of ejaculates from three Duroc boars were collected by a glove-hand technique. Samples with more than 80% motile sperm were used for this experiment. Semen was diluted with freezing extender (LEY) containing 11% (v/v) lactose, 20% (v/v) hen egg yolk with 3.5% (v/v) glycerol, and 0.5% (v/v) Orvus Es Paste(OEP, Nova Chemical Sales Inc., Scituate, MA. USA) to yield a final sperm concentration of 5×108 cells/ml. Following complete dilution, semen samples were loaded in 0.5 ml French medium straws (IMV technologies, France) and transferred to programmable semen freezer (SY-LAB Gerate GmbH, Austria). For freezing the semen samples, each straw was cooled from 5℃ to — 5℃ at 6℃/min, auto-seeding at — 5℃ and held for 60sec, samples were then cooled from — 5 to — 80℃ at 40℃/min, and thereafter from — 80℃ to — 150℃ at 60℃/min. The yolks used were sourced from fresh chicken and duck eggs. To evaluate the post-thaw sperm quality, semen was thawed at 38℃ for 20 sec and sperm motility, viability and acrosome integrity were assessed. Motility was assessed for %motile cell characteristics using computer-assisted semen analysis (CASA; SAIS SI-100, Medical supply, Korea). The percentage of sperm viability was assessed using LIVE/DEAD® sperm viability kit (Molecular probes, Eugene, OR, USA). The acrosome integrity was assessed by FITC-PNA staining. Sperm quality in terms of motility, viability and acrosome integrity showed higher after freezing in medium containing duck yolk than chicken yolk. However, there was no significant difference in sperm quality for the different types of yolk(p>0.05). * The result of this study showed that there was no significant difference between the egg yolk types when considering the sperm motility, viability and acrosome integrity of boar semen frozen in the freezing extender with chicken or duck egg yolks.
본 연구는 돼지 정자 동결시 taurine과 a-tocopherol의 첨가가 융해후 정자 성상과 정자 기능 활성산소계(reactive oxygen species; ROS)의 발생 정도 및 지질 산화(lipid peroxidation, LPO)에 미치는 영향을 구명하기 위하여 시행하였다. 1차 및 2차 희석액내 taurine과 a-tocopherol이 첨가된 돼지 동결정액의 융해 후 정자 운동성 양상, 정자 생존성, 정자 기법을 적용하여 다음과 같은 결과를 얻었다. Taurine(25mM, 50mM), a-tocopherol(500㎛, 1,000㎛) 단일처리군 그리고 taurine과 a-tocopherol의 혼합처리군(25mM~500㎛, 50mM~1,000㎛)은 동결ㆍ융해 후 대조군과 비해 정자 운동성과 생존성은 유의적인 차이를 나타내지 않았다. Taurine과 a-tocopherol의 혼합처리군 50mM~1,000㎛에서 HOST, 점체 반응이 대조군과 비교하여 유의차는 인정되지 않았으나 다소 증가하였다. 동결ㆍ융해 정자의 ROS 발생 억제를 위한 taurine과 a-tocopherol의 모든 처리군은 대조군과 비교하여ㆍO₂- 발생을 유의적으로 완화시키지 못하였다. 그러나 taurine 단일처리군(25mM), a-tocopherol 단일처리군(50mM,1,000㎛)과 혼합처리군(25mM~50mM,50mM~1,000㎛)은 H₂O₂의 발생을 대조군과 비교하여 유의적으로 완화시켰다(P<0.05). 동결ㆍ융해 정자의 malondialdehyde의 생산은 taurine과 a-tocopherol의 모든 처리군에서 대조군과 비교하여 유의적인 감소를 보였다(P<0.05). 이상의 결과를 종합해 보면 돼지 정액의 동결보존시 taurine와 a-tocopherol 같은 항산화제의 처리는 ROS 발생과 LPO을 효과적으로 완화시킴에 따라 돼지 정액의 동결보존 효율을 증진시킬 수 있는 유용한 방법이라 사료된다.
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
본 연구에서는 보다 효율적인 동결 보존법을 수립하기 위하여 현재 사용되는 동결 보존액과 동결방법을 정자의 운동성 측면에서 비교해 보았다. 즉, 세 종류의 조성이 다른 동결보존액인 TYB, dithiothreitol을 첨가한 TYB+DTT, KS II 등이 동결보존 전후에 있어 운동성에 미치는 영향을 조사하였으며, 또한 vapor freezing 방법과 computerized freezer를 사용한 동결방법이 정자 운동성에 미치는 영향을 알아보았다. 정자