• 대한생식의학회:학술대회논문집
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• 2001.11a
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• pp.57-62
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• 2001

One of recent advances of mammalian fertilization is the understanding of the molecular basis of fertilization. Several proteins localized in sperm nucleus or on sperm surface are necessary for the fertilization process. Protamines, sperm nuclear proteins, are required for normal sperm function that leads to fertilization. Fertilin and cyritestin are sperm surface proteins and essential for sperm-egg binding. Fertilin is also required for sperm transport in the female reproductive tracts. Metalloproteses on sperm plasma membrane are found to play a role in sperm-egg fusion. The functional analysis of these proteins provides a new insight into the molecular mechanisms underlying mammalian fertilization and male fertility.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.2
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• pp.110-116
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• 2022

Objective: Sperm vitrification leads to the production of reactive oxygen species (ROS) that can damage the functional parameters of sperm. The present study aimed to investigate the antioxidant effect of Nigella sativa extract on motility, plasma membrane function, mitochondrial membrane potential (MMP), DNA damage, and intracellular ROS production. Methods: A total of 20 sperm samples were used. Samples were divided into six experimental groups, including groups with aqueous extract from N. sativa seeds at concentrations of 1% to 6%, a cryopreserved control group, and a fresh control group. Results: Statistical analysis showed significantly higher total sperm motility at concentrations of 3% to 6% than in the vitrified semen control group. Additionally, progressive motility and all motion characteristics at all concentrations were significantly higher than in the vitrified semen control group. The presence of N. sativa seed extract also improved the quality of the sperm parameters assayed in all experimental groups (1%-6%; intracellular ROS production, DNA damage, MMP, and sperm membrane function) compared to the control group. Conclusion: Higher concentrations of N. sativa led to improvements in all sperm parameters and sperm quality. These findings indicate that N. sativa seed extract is effective for improving the quality of sperm after vitrification.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.2
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• pp.105-115
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• 2002

Objective : To evaluate the effects of the reactive oxygen species (ROS) generated with a xanthine (X) and xanthine oxidase (XO) system on sperm function, the change of sperm characteristics, lipid peroxidation, and DNA fragmentation in bovine spermatozoa. Materials and Methods: ROS were produced using a combination of 1000 uM X and 50 mU/ml XO. The ROS scavengers: superoxide dismu tase (SOD) (200 U/ml) and catalase (500 U/ml) were also tested. Spermatozoa were incubated for 2 hours in BWW medium with a combination of X-XO supplemented with or without ROS scavengers at $37^{circ}C$ under 5% $CO_2$ incubator. Sperm movement characteristics by CASA (computer-aided sperm analysis), HOST (hypoosmotic swelling test), Caionophore induced acrosome reaction, malondialdehyde formation for the analysis of lipid peroxidation, the percentage of DNA fragmentation using the method of TdT-mediated nick end labelling (TUNEL) by flow cytometry were determined after 2 hours incubation. Results: The action of ROS on bovine spermatozoa resulted in a decreased in capacity for sperm motility, Ca-ionophore induced acrosome reaction and membrane integrity, an increased in malondialdehyde formation and the percentage of sperm with DNA fragmentation. In the effects of antioxidant, catalase completely alleviated the toxic effects induced by the ROS in terms of sperm function and characteristics, however SOD exhibited no capacity to reduce the toxic effects. Conclusion: The ROS can induce significant damages to sperm functions and characteristics. The useful ROS scavengers can minimized the defects of sperm function and various damages of spermatozoa.

• Journal of Embryo Transfer
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• v.33 no.4
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• pp.337-342
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• 2018

Cryopreservation is mainly used for preservation of boar sperm. However, this method stresses the sperm by reactive oxygen species (ROS), and the conception rate and the litter size are not more efficient than the liquid preservation of spermatozoa. Therefore, we use chitosan which is a natural product derived antioxidant compound. We used GnHA (chitosan+hyaluronic acid) and GnHG (chitosan hydrogel) as chitosan complexes to cryopreserve boar sperm for improve sperm metabolism and function. Sperm parameter (sperm motility, progressive motility, path velocity, straight-line velocity, curvilinear velocity) is measured by computer-assisted sperm analysis (CASA) using frozen sperm with GnHA or GnHG (0, 0.25, 0.5, 1 mg/mL), respectively. Also, lipid peroxidation analysis using malondialdehyde (MDA) is performed to confirm the antioxidative effect of chitosan in frozen spermatozoa. CASA analysis showed GnHA and GnHG are effective against cryopreserved boar sperm. And antioxidant effect is measured by lipid peroxidation analysis. GnHA and GnHG, which is chitosan complex are effective for boar sperm cryopreservation by antioxidant effect.

• Journal of Animal Science and Technology
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• v.64 no.2
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• pp.235-246
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• 2022

In this study, we used more reliable experimental materials and methods to detect the effects of osteopontin (OPN) on boar sperm in vitro capacitation, acrosome reaction, and fertilization efficiency. We reorganized and obtained the OPN protein of the porcine source. Immunofluorescence and Western blot show the localization and expression of the OPN protein before and after sperm capacitation. To determine whether OPN can affect sperm during sperm capacitation, we examined cyclic adenosine monophosphate (cAMP) concentrations after sperm capacitation, and the results showed that OPN significantly increased the cAMP concentration in sperm (p < 0.05). Flow cytometry showed that 0.1 ㎍/mL OPN-treated sperm had better acrosome reaction ability. In vitro fertilization (IVF) showed that 0.1 ㎍/mL OPN significantly increased the rate of embryo division. In conclusion, this study found that 0.1 ㎍/mL porcine OPN protein can significantly improve porcine capacitated sperm motility, cAMP concentration after capacitation sperm, acrosome reaction ability, and embryo division during IVF and provides new clues to explore the mechanism of OPN's function on sperm.

• Clinical and Experimental Reproductive Medicine
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• v.51 no.1
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• pp.13-19
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• 2024

Radiofrequency electromagnetic radiation (RF-EMR) from various sources may impact health due to the generation of frequency bands. Broad pulses emitted within frequency bands can be absorbed by cells, influencing their function. Numerous laboratory studies have demonstrated that mobile phones-generally the most widely used devices-can have harmful effects on sex cells, such as sperm and oocytes, by producing RF-EMR. Moreover, some research has indicated that RF-EMR generated by mobile phones can influence sperm parameters, including motility, morphology, viability, and (most critically) DNA structure. Consequently, RF-EMR can disrupt both sperm function and fertilization. However, other studies have reported that exposure of spermatozoa to RF-EMR does not affect the functional parameters or genetic structure of sperm. These conflicting results likely stem from differences among studies in the duration and exposure distance, as well as the species of animal used. This report was undertaken to review the existing research discussing the effects of RF-EMR on the DNA integrity of mammalian spermatozoa.

• Journal of Veterinary Clinics
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• v.28 no.6
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• pp.571-575
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• 2011

Sperm cryopreservation methods have been improved over the last few decades. However, an optimized thawing rate has not yet been established. Therefore, we investigated the effect of thawing rate on sperm function after cryopreservation. The ejaculates collected from beagle dogs were cryopreserved and then thawed at two different thawing rates ($37^{\circ}C$ for 1 min or $70^{\circ}C$ for 15 sec). The thawed sperm were evaluated for motility, viability, morphology, plasma membrane integrity, phosphatidylserine (PS) translocation, and intracellular $H_2O_2$ level. The sperm thawed rapidly at $70^{\circ}C$ showed improved motility, viability, normal morphology, plasma-membrane integrity and non-PS translocation compared to the sperm thawed slowly at $37^{\circ}C$ (P < 0.05). However, the intracellular $H_2O_2$ levels were not significantly different between the rapid- and slow-thawed sperm (P > 0.05). In conclusion, sperm rapid thawing at $70^{\circ}C$ could improve the function of cryopreserved canine sperm, and the appropriate thawing rate would enhance the quality of the cryopreserved sperm.

• Animal Bioscience
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• v.34 no.8
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• pp.1253-1270
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• 2021

Assessment of male fertility is based on the evaluation of sperm. Semen evaluation measures various sperm quality parameters as fertility indicators. However, semen evaluation has limitations, and it requires the advancement and application of strict quality control methods to interpret the results. This article reviews the recent advances in evaluating various sperm-specific quality characteristics and methodologies, with the help of different assays to assess sperm-fertility status. Sperm evaluation methods that include conventional microscopic methods, computer-assisted sperm analyzers (CASA), and flow cytometric analysis, provide precise information related to sperm morphology and function. Moreover, profiling fertility-related biomarkers in sperm or seminal plasma can be helpful in predicting fertility. Identification of different sperm proteins and diagnosis of DNA damage has positively contributed to the existing pool of knowledge about sperm physiology and molecular anomalies associated with different infertility issues in males. Advances in methods and sperm-specific evaluation has subsequently resulted in a better understanding of sperm biology that has improved the diagnosis and clinical management of male factor infertility. Accurate sperm evaluation is of paramount importance in the application of artificial insemination and assisted reproductive technology. However, no single test can precisely determine fertility; the selection of an appropriate test or a set of tests and parameters is required to accurately determine the fertility of specific animal species. Therefore, a need to further calibrate the CASA and advance the gene expression tests is recommended for faster and field-level applications.

• Toxicological Research
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• v.25 no.4
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• pp.203-207
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• 2009

Present study was conducted to investigate potential effects of epichlorohydrin on testicular and epididymal function in male rats. The test chemical was administered to adult male rats by gavage at dose levels of 0, 3.125, 12.5, and 50 mg/kg/day for 7 days. Testicular and epididymal function were assessed by measurement of reproductive organ weight, testicular spermatid count, epididymal sperm count, motility and morphology, and histopathology in rats. At 50 mg/kg, a decrease in the sperm motility and an increase in the incidence of sperm abnormalities were observed. Histopathological examinations revealed an increase in the incidence of histopathological changes including cell debris in the ducts, vacuolization of the epithelial cells, oligospermia, and epithelial disruption in the proximal caput epididymidis. At 12.5 mg/kg, an increase in the incidence of histopathological changes of the epididymidis was found. There were no treatment-related effects at 3.125 mg/kg. These results show that 7-day repeated oral administration of epichlorohydrin to male rats results in adverse effects on sperm motility, sperm morphology, and epididymal histology at $\geq$ 12.5 mg/kg/day.

• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.307-316
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• 2022

The misuse of pesticides has resulted in environmental pollution, which directly or indirectly affects all life on earth. Chlorpyrifos is a chlorinated organophosphorus pesticide that is commonly used in agriculture. The aim of this study was to investigate the effects of chlorpyrifos on the fertilization function of boar spermatozoa. Sperm samples from boars were subjected to varying concentrations of chlorpyrifos from 10 to 200 µM for two incubation periods, 30 min or 2 hrs. The boar spermatozoa were then evaluated for motility, motion kinematics, viability, acrosome integrity, chromatin stability, and generation of intracellular reactive oxygen species (ROS). There was a significant percentage reduction in sperm motility and motion kinematic parameters after both incubation periods (p < 0.05). The proportion of viable spermatozoa decreased after incubation for 30 min and 2 hrs in a dose-dependent manner (p < 0.05). A significantly lower percentage of normal acrosomes was observed in spermatozoa exposed to 200 µM chlorpyrifos over both incubation periods, compared to the controls. The damage to sperm DNA was significantly higher when the exposure time to chlorpyrifos was longer. There was a significant increase in the ROS levels in spermatozoa incubated with chlorpyrifos for 2 hrs (p < 0.05). From the results of the present study, it is concluded that direct exposure of boar spermatozoa to chlorpyrifos altered boar sperm characteristics, suggesting potential toxicity that may affect the male reproductive function.