• Animal Bioscience
• /
• v.36 no.3
• /
• pp.385-403
• /
• 2023

Male fertility is affected by multiple endogenous stressors, including reactive oxygen species (ROS), which greatly deteriorate the fertility. However, physiological levels of ROS are required by sperm for the proper accomplishment of different cellular functions including proliferation, maturation, capacitation, acrosomal reaction, and fertilization. Excessive ROS production creates an imbalance between ROS production and neutralization resulting in oxidative stress (OS). OS causes male infertility by impairing sperm functions including reduced motility, deoxyribonucleic acid damage, morphological defects, and enhanced apoptosis. Several in-vivo and in-vitro studies have reported improvement in quality-related parameters of sperm following the use of different natural and synthetic antioxidants. In this review, we focus on the causes of OS, ROS production sources, mechanisms responsible for sperm damage, and the role of antioxidants in preserving sperm fertility.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.3
• /
• pp.351-358
• /
• 2007

Carbohydrate-protein interactions are known to be important in gamete interactions. Several evidence indicated that a fucose-containing sulfated polysaccharide fucoidan was potential inhibitor of fertilization in vitro and thus fucose seemed to be part of the recognition signal of gamete interaction in mammals. In recent investigation we found that ${\alpha}$-L-fucosidase activity was present in boar spermatozoa and it was related to sperm binding to and penetration into zona pellucida (ZP) in vitro. The objective of this study was to determine the effects of monosaccharide L-fucose and polysaccharide fucoidan on sperm ${\alpha}$-L-fucosidase activity and relation to sperm-oocyte interaction in pig. Results indicated that the activity of sperm ${\alpha}$-L-fucosidase was largely inhibited (62%) when sperm suspension was treated with monosaccharide L-fucose. It also significantly inhibited the number of sperm binding to ZP (32%) and penetration into zona-intact oocytes (72%), but did not inhibit penetration into zona-free oocytes when fertilization medium contained L-fucose. The chlorotetracycline (CTC) assessment showed that L-fucose did not affect induction of sperm capacitation and acrosome reaction. In contrast, the activity of sperm ${\alpha}$-L-fucosidase was not inhibited when sperm suspension was treated with polysaccharide fucoidan but sperm-ZP binding was greatly inhibited (85%) and completely blocked sperm penetration into zona-intact or zona-free oocytes. The CTC assessment showed that fucoidan increased the F pattern and decreased the AR pattern sperm. These results suggested that the different inhibitory mechanisms were present between monosaccharide L-fucose and polysaccharide fucoidan on sperm-oocyte interaction, the inhibition effect of ${\alpha}$-L-fucose on sperm binding and penetrating into ZP caused sperm ${\alpha}$-L-fucosidase inhibited by ${\alpha}$-L-fucose.

• Korean Journal of Animal Reproduction
• /
• v.10 no.2
• /
• pp.204-210
• /
• 1986

As a part of in vitro fertilization(IVF) for farm animals, IVF experiment was conducted using New Zealand white rabbits with their sperm capacitated in vivo. The effect of uterine conditions on sperm capacitation and effect of sperm concentration and fertilization media on IVF rate and implantation of in vitro fertilized ova were studied. The results obtained are summarized as follows; 1. Acrosomal reaction, noted after staining, of sperm recovered from ligated and intact uterus of capacitators was 83.0% and 65.7%, respectively. 2. IVF rate of ova inseminated with sperm from ligated uterus tended to be higher in DM or with higher concentration of sperm than in the modified F12 medium or with lower sperm concentration. Cleavage rate of fertilized ova for 48hr in DM was 31.5% for 106/ml and 30.0% for 104/ml of sperm and that in modified F12 medium was 26.0% for 106/ml and 22.3% for 104/ml of sperm. 3. Using the sperm from intact uterus, cleavage rate of fertilized ova showed same tendency as those shown with ligated uterus. The rate was 82.0% for 106/ml and 66.5% for 104/ml of sperm in DM and was 69.0% for 106/ml and 56.5% for 104/ml of sperm in the medium. 4. When normal ova up to 48hr after IVF were cultured for 4 days in either DM or modified F12 medium, ova developed to blastocyst stage showed higher rate in the groups of higher sperm concentration in the both media. The rate was 80.9% and 60.0% for 106/ml and 104/ml of sperm in DM and 91.7% and 71.4% for 106/ml and 104/ml of sperm in the modified F12 medium, respectively. 5. Rate of implantation after transfer of 4- or 8-cell embryos was 36.8%.

• Korean Journal of Animal Reproduction
• /
• v.10 no.1
• /
• pp.109-120
• /
• 1986

This study was conducted to define the effect of addition of lysolecithin (LC) and 20% v/v rabbit serum to sperm preincubation medium on the induction of acrosome reaction (AR) an fertilizing ability in vitro of LG-added sperm. Ejaculated rabbit sperm from New Zealand White buck was washed once by centrifugation, then preincubated for 2 or 4 hrs in a chemically defined medium (DM), DM plus 20% rabbit serum or BSA-free DM plus 20% rabbit serum at 37$^{\circ}C$ water bath or CO2 incubator. At the end of preincubation LC was added to the preincubated sperm, which was stained at 0.5 to 4 hr later and examined for AR and sperm motility. For in vitro fertilization, gametes were coincubated in DM up to 24 hrs and thereafter fertilized embryos were incubated in BSM -II up to 48 hrs. Addition of LC to 4-hr preincubated sperm was more effective for the AR and sperm motility than that to 2-hr preincubated sperm and optimal concentration of LC for AR was about 80${\mu}$g/ml. A significant increase in AR occured from 20 to 30 min. after addition of 80 to 100${\mu}$g/ml in 4-hr preincubated sperm. BSA-free DM plus 20% rabbit serum showed a higher AR and sperm motility than those of DM plus 20% rabbit serum in LC-added sperm after 4-hr preincubation. The incidence of AR after 4-hr preincubation and at 30 min after 60${\mu}$g/ml LC addition varied greatly among individual bucks. Sixty ${\mu}$g/ml LC-added sperm showed a slight high cleavage rate over control levels, but 100${\mu}$g/ml LC-added sperm showed lower cleavage rate rather than 60${\mu}$g/ml LC. It is concluded that optimal concentration of LC for high AR induction and sperm motility in 4-hr preincubated sperm was about 80${\mu}$g/ml, but 60${\mu}$g/ml level was more useful for in vitro fertilization.

• Clinical and Experimental Reproductive Medicine
• /
• v.27 no.4
• /
• pp.393-403
• /
• 2000

Objective: To investigate the effects of ROS on kinematic parameters in human spermatozoa. To verify the changes in above parameters, human spermatozoa were incubated with xanthine-xanthine oxidase (X-XO), $H_2O_2$, sodium nitroprusside (SNP) or lymphocyte. Otherwise, spemlatozoa were incubated under low $O_2 (5%) condition. Methods: CASA was employed to analyze sperm motion parameters. Results: Under $H_2O_2 treatment, all kinematic parameters of spermatozoa were dramatically increased during 30 min, but gradually decreased thereafter. Under the low concentration of $H_2O_2 (125 ${\mu}M$ and 250 ${\mu}M$), the movement velocity (VAP, VCL, VSL) decreased, but forward movement increased. Under the 1mM $H_2O_2, sperm showed reduced kinematic parameters except during first 30 min of incubation. In the cases of X-XO and SNP treatment, the movement velocity increased but the forward movement reduced. After incubation for 3 hr treatment, the kinematic parameters gradually decreased in high concentration of X-XO. However these parameters maintained or increased in low concentration of X-XO. There was no obvious changes in the above parameters in the high concentration of SNP. In the presence of high concentration of lymphocytes, all parameters decreased. Under the 5% $O_2 condition, the parameters of the movement velocity and movement pattern increased, but forward movement decreased. Taken togethers, it suggested that ROS increased the movement velocity but decreased the forward movement and lateral head replacement. $H_2O_2, X-XO, SNP and lymphocyte treatment significantly increased capacitated spermatozoa within I h of incubation. There was no significant difference in capacitation between low- and high $O_2 group. Conclusion: The early onset of capacitation in the presence of ROS suggest that ROS might be a positive regulator of sperm capacitation and hyperactivation. These results demonstrate that low concentration ROS facilitates the movement velocity but high concentration ROS was inhibitory.

• Clinical and Experimental Reproductive Medicine
• /
• v.26 no.1
• /
• pp.21-29
• /
• 1999

This study was performed to identify the effect of the hydrosalpinx fluid on sperm motility. It has been reported that the patients with hydrosalpinx show the outstandingly lower success rate than other patients having infertility by different factors. It is unclear that the cause of it is influenced by hydrosalpinx fluid directly or by secondary chronic inflammation of endometrium. We wanted to know if the hydrosalpinx fluid influences sperm motility parameters directly such that it is related to the development of infertility. Therefore, using computer assisted semen analyzer (CASA), we observed, from February to July, 1997, how sperm motility, sperm progressive motility, sperm curvilinear velocity, sperm lateral head displacement, sperm straightness and sperm linearity change after treating normal sperm with hydrosalpinx fluid to evaluate sperm function on infertility. The result was that the study group (n=32) has the tendency to differ from the control group (n=32) on sperm motility, progressive motility, curvilinear velocity, lateral head displacement, straightness and linearity. We concluded that the hydrosalpinx fluid, with varying degree, directly has the harmful effects on sperm motility parameters, that is, curvilinear velocity, lateral head displacement and linearity of sperm which are related to the hyperactivation, hence decreased capacitation.

• Korean Journal of Veterinary Research
• /
• v.39 no.1
• /
• pp.220-225
• /
• 1999

The aim of these experiments was to investigate the effects of bovine oviduct epithelial cells (OEC) derived from different segments to bind sperm binding and maintain their motility in vitro. In experiment 1, the number of sperm attached to OEC derived from isthmus or ampulla, the motility of unattached sperm during co-culture and fertilizing ability were assessed. In experiment 2, heparin treated sperm (hsp) or no treated sperm (nsp) were used to evaluate OEC binding ability of capacitated sperm. In experiment 1, regardless of their origin, approximately 65% of the sperm were attached to OEC within 2h. From 6h of co-culture, the numbers of unattached sperm on ampullary OEC were significantly higher than those on isthmic OEC (p<0.005). From 12h of co-culture, the motility of unattached sperm on isthmic OEC were significantly higher than those on ampullary OEC(p<0.05). The cleavage rate of oocytes inseminated on OEC derived from isthmic segment was also significantly higher than those from ampullary segment (p<0.01). In experiment 2, the numbers of unattached hsp on OEC were significantly higher than those of controls (p<0.01), between 2-24h examination. From 12h of co-culture, the motility of unattached nsp were significantly greater than those of hsp (p<0.01). These results show that bovine OEC derived from the isthmus play more important role(s) for sperm binding, maintaining motility and fertilization in vitro than those from the ampulla, and heparin induced capacitation may change sperm binding ability on OEC in vitro.

• Journal of Embryo Transfer
• /
• v.26 no.1
• /
• pp.71-78
• /
• 2011

This study was undertaken to find out the effect of cholesterol and serum albumin on sperm ability and lipid peroxidation levels period to the liquid storage of miniature pig sperm. Ejaculated semen from miniature pigs was collected by gloved-hand method into a pre-warmed ($37^{\circ}C$) thermos bottle, and extended with Modena solution {with and without BSA, methyl-beta-cyclodextrin (-cholesterol) and cholesterol loaded cyclodextrin (+cholesterol)}. Each semen was assessed for viability (SYBR-14/PI staining) and acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining at 1, 3, 5, 7 and 10 days of storage. At for the effects of cholesterol and serum albumin on lipid peroxidation, semen were incubated with $H_2O_2$ ($10\;{\mu}M$), and lipid peroxidation level were measured by flow cytometry using the lipid peroxidation reporter probe $C_{11}-BODIPY^{581/591}$. The result, lipid peroxidation level in sperm added with cholesterol were lower in $10\;{\mu}M$ $H_2O_2$ compared to the added sperm with serum albumin. Also, added cholesterol to sperm had significant (p<0.05) higher viability when storage for 7 and 10 days and lower when 10 days of storage percentage of acrosome-reacted sperm (AR pattern) in acrosome state as say result compared to other treated groups. In conclusion, role of cholesterol during lipid storage in miniature pig spermatozoa was protected boar spermatozoa from lipid peroxidation prior to lipid storage. Addition serum albumin during lipid storage in sperm may be induce sperm membrane damage by lipid peroxidation. Therefore, addition of cholesterol to miniature pig sperm will be lead to extension of liquid storage periods.

• Clinical and Experimental Reproductive Medicine
• /
• v.18 no.1
• /
• pp.63-71
• /
• 1991

To establish the normal fertile range in the results of the sperm zona-free hamster ova penetration assay (SPA) in Korean male, SPA using the low temperature ($4^{\circ}C$) capacitation in TEST-yolk buffer (TYB) was performed in 67 fertile and 26 infertile men. Sperm parameters in routine semen analysis were also checked and compared with the results of SPA. Sperm concentration, motility and motility index (MI) were significantly higher in fertile group compared with infertile group: $96.0{\pm}46.6$ vs $43.6{\pm}31.9{\times}10^6/ml$, $65.5{\pm}14.8%$ vs $45.8{\pm}23.6%$ and $46.31{\pm}13.29$ vs 27.40{\pm}17.98$, respectively. In fertile group, the hamster ova penetration rate (PR) was $98.5{\pm}5.0%$ (80%-100%), and the penetration index (mean penetrations per ovum, PI) was $9.59{\pm}6.35$(3.1-29.0). All the fertile men showed PI>3.0. In infertile group, PR was $24.6{\pm}24.8%$ (0%-70%), and PI was $0.40{\pm}0.42$ (0-1.3). Both PR and PI were significantly lower in infertile group. There was a significant correlation beween PI and sperm motility or MI, respectively, in fertile group whereas there was no correlation in infertile group. These data suggest that SPA using the low temperature capacitation in TYB can be a valuable diagnostic tool for the assessment of male fertility in vitro and provide an important supplement to the traditional tests of sperm quality.

• Development and Reproduction
• /
• v.5 no.1
• /
• pp.53-57
• /
• 2001

Sperm capacitation and acrosome reaction (AR) have been known to be Ca$^{2+}$-dependent events. Sperm capacitation accompanies with cholesterol efflux fiom plasma membrane, that eventually stimulates AR. However, whether the AR mediated by cholesterol efflux is Ca$^{2+}$ dependent has not been verified yet. Recently, methyl beta cyclodextrin (MBCD) was found to evoke AR by stimulating the cholesterol efflux fiom sperm membrane. In the present study, we examined the requirement of Ca$^{2+}$ in the MBCD-induced AR. During incubation of sperm in the bicarbonate buffered media MBCD increased AR in a dose-dependent manner regardless of the Ca$^{2+}$ presence. In the presence of low molar concentration of Ca$^{2+}$ (100 ${\mu}$M), MBCD-induced AR was slightly increased compared to Ca$^{2+}$-free condition. In the absence of Ca$^{2+}$ supplement, spontaneous AR was slightly increased during the incubation but inhibited by 100 ${\mu}$M EGTA. MBCD potentiated AR even the presence of EGTA. However, EGTA attenuated MBCD-induced AR, suagesting the functional involvement of intracellular Ca$^{2+}$ in the MBCD-induced AR. Taken together, it was suggested that cholesterol efflux from the sperm plasma membrane was sufficient for induction of AR even in the absence of extracellular Ca$^{2+}$and that a condition permissive for mobilization of intracellular Ca$^{2+}$ is important for MBCD-induced AR.