Effects of hydroxytyrosol on post-thaw quality of rooster sperm.

Semen cryopreservation is one of the most important reproduction techniques in the livestock and poultry industry. Cryopreservation induces cold stress, generating reactive oxygen species (ROS) and oxidative stress causing structural and biochemical damages in sperm. In this study, we evaluated the effects of the hydroxytyrosol (HT), as an antioxidant, at the concentrations of 0, 25, 50, and 100 µg/mL on post-thaw semen quality metrics in rooster. Semen samples were collected twice a week from 10 roosters (29 weeks), processed and frozen according to experimental groups. Different quality parameters, including total motility, progressive motility, viability, morphology, membrane integrity, and malondialdehyde were measured after thawing. Results showed that 25 and 50 µg/mL of HT produced the highest percentage of total motility (51.01 ± 2.19 and 50.15 ± 2.19, respectively) and progressive motility (35.74 ± 1.34 and 35.15 ± 1.34, respectively), membrane integrity (48.00 ± 2.18 and 46.75 ± 2.18, respectively) as well as viability (53.00 ± 2.17 and 52.50 ± 2.17, respectively) compared with the other groups (p < .05). The group with 25 µg/mL of HT showed the lowest significant (p < .05) MDA concentration (1.81 ± 0.25). Our results showed that the effect of HT was not dose-dependent and optimum concentration of HT could improve functional parameters of rooster sperm after freezing-thawing. These findings suggest that HT may have protective effects on the rooster sperm during the freezing-thawing process.

Effects of different extenders on epigenetic patterns and functional parameters of bull sperm during cryopreservation process.

The cryopreservation process induces alterations in cellular parameters and epigenetic patterns in bull sperm, which can be prevented by adding cryoprotectants in the freezing extenders. The purpose of this study was to compare the protective effects of two extenders based on soybean lecithin (SLE) and egg yolk (EYE) on epigenetic patterns and quality parameters of sperm such as motility parameters, mitochondrial membrane integrity, DNA fragmentation, viability, and apoptotic-like changes of bull sperm after cryopreservation. Results demonstrated that cryopreservation significantly (p < .05) reduced the level of DNA global methylation, H3K9 histone acetylation, and H3K4 histone methylation in both frozen groups compared to the fresh sperm. Also, the level of H3K9 acetylation was lower in the frozen SLE group (21.2 ± 1.86) compared to EYE group (15.2 ± 1.86). In addition, the SLE frozen group had a higher percentage of viability, progressive motility, and linearity (LIN) in SLE frozen group compared to EYE frozen group. However, no difference was observed in mitochondrial membrane integrity and DNA fragmentation between SLE and EYE frozen groups. While soybean-lecithin-based extender showed some initial positive impacts of epigenetics and semen parameters, further investigations can provide useful information for better freezing.

Cryopreservation of bovine semen using extract of Cinnamomum zeylanicum.

BACKGROUND: Antioxidants minimise oxidative stress and enhance sperm quality in the process of cryopreservation. OBJECTIVE: To assess the impact of Cinnamomum zeylanicum extract as an additive during the post-dilution and post-thaw stages of Murrah buffalo semen cryopreservation. MATERIALS AND METHODS: The semen sample was diluted using Tris-Egg-Yolk-Citric-Acid-Fructose-Glycerol extender and subsequently divided into three groups: Group 1, TEYCAFG without any additives or controls (C); Group 2, TEYCAFG fortified with a 50 ug/mL aqueous extract of cinnamon (T1); and Group 3, TEYCAFG fortified with a 50 ug/mL ethanolic extract of cinnamon (T2). The evaluation included an assessment of progressive motility, live spermatozoa, sperm abnormalities, HOST, CMPT, and enzyme leakage (GOT and GPT) at both the post-dilution and post-thaw stages. RESULTS: The groups that received cinnamon supplementation demonstrated statistically significant improvements (p<0.05) in various parameters, including an increase in the progressive motility, live spermatozoa, and HOS-positive spermatozoa, as well as greater distance traveled by vanguard spermatozoa compared to the control group. Furthermore, the cinnamon-added groups exhibited a significant decrease (p<0.05) in the percentage of sperm abnormalities and lower enzyme leakage (GOT and GPT) in post-thawed semen. CONCLUSION: Aqueous extract of C. zeylanicum at a concentration of 50 µg/mL provides superior protection of sperm structures and functions as compared to both the ethanolic extract of C. zeylanicum at the same concentration and the control group. Doi.org/10.54680/fr24310110712.

Aquaporin expression in cryopreserved human sperm: exploring the capabilities of natural deep eutectic solvents (NADEs).

BACKGROUND: Aquaporins (AQPs) are essential proteins that facilitate the rapid movement of water and cryoprotective agents (CPAs) during the cryopreservation process, and ensure the cryo-tolerance of sperm cells. OBJECTIVE: This study evaluated the preservation of aquaporin levels in human sperm after undergoing freezing using natural deep eutectic solvents (NADES) as CPAs for cryoprotection. MATERIALS AND METHODS: From June 2021 to October 2022, 35 semen samples with normal sperm parameters were acquired from the Mehr Infertility Treatment Institute in Rasht, Iran. The samples were divided into several groups for analysis: control group (not frozen), group frozen with SpermFreeze Solution, and groups frozen with different NADESs, including ChS, ChX, ChU, ChG, GlyP, and EtP. After thawing, various aspects for each group were assessed, including the integrity and condensation of sperm chromatin, viability, motility, integrity of acrosome, and the expression of AQP1, AQP3, AQP7, AQP8, and AQP9 genes. RESULTS: The analysis of gene expression revealed that freezing with ChS and GlyP preserved the expression of the AQP1 and AQP3 genes compared to the control group. Regarding AQP7 and AQP8, significant differences were not observed in expression levels between certain NADES groups (e.g., ChS, ChU, and GlyP) and the control group. Additionally, samples frozen with specific NADESs, such as ChS, ChG, EtP, and GlyP, exhibited preserved levels of AQP9 expression when compared to the control group. CONCLUSION: These findings emphasize the importance of NADES in preserving the expression of aquaporins in cryopreserved human sperm and their important fertility parameters. Doi.org/10.54680/fr24310110512.

Enhancement of Frozen-Thawed Human Sperm Quality with Zinc as a Cryoprotective Additive.

BACKGROUND Cryopreservation preserves male fertility, crucial in oncology, advanced age, and infertility. However, it damages sperm motility, membrane, and DNA. Zinc (Zn), an antioxidant, shows promise in improving sperm quality after thawing, highlighting its potential as a cryoprotectant in reproductive medicine. MATERIAL AND METHODS Gradient concentration of ZnSO4 (0, 12.5, 25, 50, and 100 µM) was added in the Glycerol-egg yolk-citrate (GEYC) cryopreservative medium as an extender. Alterations in sperm viability and motility parameters after cryopreservation were detected in each group. Sperm plasma membrane integrity (PMI), acrosome integrity (ACR), DNA fragment index (DFI), and changes in sperm mitochondrial function were examined, including: mitochondrial potential (MMP), sperm reactive oxygen species (ROS), and sperm ATP. RESULTS We found that 50 µM ZnSO4 was the most effective for the curvilinear velocity (VCL) and the average path velocity (VAP) of sperm after cryo-resuscitation. Compared to the Zn-free group, sperm plasma membrane integrity (PMI) was increased, DNA fragmentation index (DFI) was decreased, reactive oxygen species (ROS) was reduced, and mitochondrial membrane potential (MMP) was increased after cryorevival in the presence of 50 µM ZnSO4. CONCLUSIONS Zn ion is one of the antioxidants in the cell. The results of our current clinical study are sufficient to demonstrate that Zn can improve preserves sperm quality during cryopreservation when added to GEYC. The addition of 50 µM ZnSO4 increased curve velocity, mean path velocity, sperm survival (or plasma membrane integrity), and mitochondrial membrane potential while reducing ROS production and DNA breaks compared to GEYC thawed without ZnSO4.

The use of sodium caseinate in the freezing of sheep semen.

The aim of this study was to assess the addition of 2% sodium caseinate in a commercial egg yolk-based medium in frozen ovine semen. Eight Dorper males were used for the study. The ejaculate was divided into two portions and frozen without (G1) or with the addition of 2% sodium caseinate (G2). Kinetic parameters were evaluated using CASA (computer-assisted sperm analysis), and membrane and acrosome integrity as well as oxidative stress were assessed using flow cytometry. After thawing, a thermoresistance test was conducted at time points T0 and T90. For the fertility test, 100 ewes were inseminated with semen from two rams selected based on in vitro parameters, one with good post-thaw quality (+70% total motility) and the other with low post-thaw quality (-55% total motility). For the fertility test, the females were divided into 4 groups for insemination: low-quality ram without caseinate (GBS = 25) and with caseinate (GBC = 25), and high-quality ram without caseinate (GAS = 25) and with caseinate (GAC = 25). Regarding the results of sperm kinetics, there was a statistically significant difference in the parameters of average path velocity (VAP) and curvilinear velocity (VCL) between the group frozen with BotuBov and the group with added caseinate. At time point T90, straight-line velocity maintained a trend (p < .06), with BotuBov® (BB group) being superior to caseinate this time, and in the linearity parameter, caseinate was superior to BotuBov®. Flow cytometry analysis showed no difference between any of the evaluated tests. In the fertility test, there was no statistically significant difference in the pregnancy rate between the BotuBOV® group (23%, 11/48) and the sodium caseinate group (BC group) (33%, 17/52), and no differences were observed in the male versus diluent interaction (p = .70). In conclusion, sodium caseinate supplementation did not influence sperm kinetic parameters and the fertility of sheep.

Impact of various cryo-preservation steps on sperm rheotaxis and sperm kinematics in bull.

Semen cryopreservation is an important tool that has massively contributed to the progression of animal reproduction, especially in cattle. Nonetheless, a large part of the sperm population suffers from cryostress and loses fertility during the process. Although bovine semen cryopreservation is more advanced than any other species, there are still some missing links in the technology knowledge. The aim of the current study was to detect the effect of cryopreservation steps on sperm rheotaxis. Semen samples were collected from sex bulls and analyzed inside a microfluidic platform with CASA after each step of cryopreservation, including control, dilution with yolk citrate, cryoprotectant addition, and cooling or freezing. The results showed that positive rheotaxis % (PR) was not affected during cryopreservation. On the contrary, the sperm kinematics of the positive rheotactic sperm undergo significant changes, as velocity parameters (VCL, VSL, and VAP) were lower in both the cryoprotectant adding and cooling/freezing steps than in the control and yolk citrate dilution steps, while progression parameters (LIN and BCF) were higher in the cryoprotectant and cooling/freezing steps than in the control and yolk citrate dilution steps. Beside these results, an interesting phenomenon of sperm backward positive rheotaxis has been observed. The results of backward sperm rheotaxis samples revealed a significant decrease in PR%, while all sperm kinematics except BCF were significantly higher than normal rheotaxis samples. Based on these results, we conclude that positive rheotactic sperm cells are the elite of the sperm population; however, they still get some sublethal cryodamage, as shown by alterations in sperm kinematics. We also suggest that the sperm-positive rheotaxis mechanism is a mixture of an active and passive process rather than a passive physical one.

Timing of semen cryopreservation: before or after processing?

Objective: Seminal cryopreservation causes significant damage to the sperm; therefore, different methods of cryopreservation have been studied. The aim of the study was to compare the effects of density gradient processing and washing/centrifugation with seminal plasma removal for cryopreservation in semen parameters. Methods: Seminal samples of 26 normozoospermic patients were divided into 3 parts: with seminal plasma; after washing/centrifugation; and after selection through density gradient. The samples were cryopreserved for at least two weeks. Motility, sperm count, morphology and viability were evaluated before cryopreservation and after thawing. Results: Density gradient processing selected motile and viable sperm with normal morphology in fresh samples (p<0.05). Cryopreservation negatively affected all sperm parameters regardless of the processing performed, and even if the sperm recovery was lower in the density gradient after the thawing, progressive motility, total motility, viability and morphology remained higher (p<0.05). Conclusion: Cryopreservation significantly compromises sperm parameters (motility, morphology, viability). In normozoospermic patients, the density gradients select better quality spermatozoa compared to other processing methods; this benefit was kept after thawing.

Enrichment of thawed boar spermatozoa with an intact membrane using Magnetic Activated Cell Sorting.

Not all boar sperm samples survive cryopreservation well. A method of eliminating damaged sperm might enable more cryopreserved boar semen to be used for pig breeding. In this study we investigated the use of Magnetic Activated Cell sorting (MACS) to eliminate damaged sperm from thawed boar semen samples. The thawed samples were mixed with Dead cell removal particles and were applied to the column in a SuperMACS II. Different fractions were collected: Original sample (O), Flow-through (FT), and Eluate (E). Sperm membrane integrity, mitochondrial membrane potential and reactive oxygen species were evaluated by flow cytometry after staining with SYBR 14 and propidium iodide, or 5', 6, 6'-tetrachloro-1, 1', 3, 3'-tetraethylbenzimidazolylcarbocyanine iodide, or hydroethidine and dichlorodihydrofluorescein diacetate, respectively. The FT samples had increased membrane integrity, a greater proportion of sperm with high mitochondrial membrane potential and a greater proportion of sperm negative for hydrogen peroxide than O samples (P<0.0001), which in turn had increased membrane integrity than E samples (P <0.0001). However, differences were seen between boars. The FT samples had increased values of live, superoxide positive sperm than O samples (P <0.0001) and O samples had greater values than E samples (P <0.0001), while there was no effect of boar. Sperm quality was best in the FT fraction, comprising approximately 32% of the sperm sample. In conclusion, although there were differences between boars, MACS separation can improve sperm quality in thawed semen samples. It would be interesting to see if this improvement is reflected in fertility outcomes.

Coenzyme Q10 preserves buck's sperm quality during cryopreservation process in plant-based extender.

Cryopreservation of small ruminant's semen is an effective strategy for distributing spermatozoa for reproductive programs, but this process decreases the fertility potential of post-thawed spermatozoa. The aim of this research was to assess the effect of different concentrations of CoQ10 in soybean lecithin (SL)-based extender on buck semen quality during cryopreservation process. Semen samples were collected from five bucks, twice a week, then diluted in the SL-based extender containing different concentrations of CoQ10 as follows: extender containing 0 µM (control, Q0), 0.1 µM (Q0.1), 1 µM (Q1), 10 µM (Q10) and 100 µM (Q100) CoQ10. Motion characteristics, membrane functionality, abnormal morphology, mitochondrial activity, acrosome integrity, viability, apoptotic-like changes, lipid peroxidation, DNA fragmentation and ROS concentration were evaluated after freeze-thawing process. The Q10 resulted in greater (P≤0.05) total motility, progressive motility, average path velocity, membrane integrity, mitochondrial activity, acrosome integrity and viability compared to the other groups. Furthermore, supplementation of freezing extender with 10 µM of CoQ10 presented lower (P≤0.05) apoptotic-like changes, lipid peroxidation, DNA fragmentation and ROS concentration compared to the other groups. Regarding to the protective effect of CoQ10 supplement during cryopreservation process, it could be explored as a potent antioxidant for cryopreservation of buck semen as it preserved the post-thawed buck sperm quality.

A brief review of the methodology and cryoprotectants in selected fish and mammalian species.

Cryopreservation is a valuable technique used to assist in the genetic improvement of cultured stocks and provide a continuous supply of good-quality semen for artificial insemination. Conserving semen by cryopreservation serves several purposes (e.g. artificial reproductive technologies and species conservation) and is also used in the clinical treatment of human infertility. However, the lifespan of cryopreserved semen is influenced by a range of factors, including storage temperature, cooling rate, chemical composition of the extender, the concentration of cryoprotectant, reactive oxygen species, seminal plasma composition and hygienic control. The choice of cryoprotectant is a vital factor underlying the success of animal semen cryopreservation. In this regard, extensive research has been carried out on various cryoprotectants, such as egg yolk, dimethyl sulfoxide, methanol, ethylene glycol and dimethylacetamide. Recent studies have also described the use of a range of new cryoprotectants for cryopreservation, including compounds of plant origin (soy), amino acids, antifreeze proteins, carbohydrates and cyclodextrins. Moreover, semen cryopreservation and storage require the use of liquid nitrogen or ultralow refrigeration methods for both long- and short-term storage. This review summarizes the general methods used for freezing semen and discusses the use of traditional and newly emerging cryoprotectants (permeable and non-permeable) for the cryopreservation of semen in selected fish and mammalian species.

Effect of fumigation height and time on cryopreservation of ram semen.

The cooling rate is a crucial factor in the process of freezing semen, influencing the overall freezing effectiveness. The height and time of fumigation can significantly impact the rate of cooling. Appropriate cooling rates can help minimize the formation of ice crystals in spermatozoa and reduce potential damage to them. Therefore, the aim of this study was to evaluate the effect of different fumigation heights and time for the cryopreservation of Hu ram semen. Experiments I-IV assessed the effect of semen cryopreservation by testing the post-thawed spermatozoa total motility (TM), progressive motility (PM) and kinetic parameters fumigated at distances of 2, 4, 6 and 8 cm for durations of 5, 10, 15 and 20 min, respectively. Based on the results of experiments I to IV, experiment V evaluated the effect of semen cryopreservation by testing the post-thawed spermatozoa TM, PM, kinetic parameters, plasma membrane integrity, acrosome integrity and reactive oxygen species (ROS) level fumigated at distances of 2, 4, 6 and 8 cm for duration of 20 min. The results indicated that fumigation at 2 cm for 20 min significantly (P < 0.05) improved spermatozoa TM, PM, mean angular displacement (MAD), plasma membrane integrity and acrosome integrity compared to other groups. Additionally, it significantly (P < 0.05) reduced spermatozoa ROS level compared to the 6 and 8 cm groups. In conclusion, fumigation for 20 min at a distance of 2 cm from the liquid nitrogen surface is the most suitable cooling method for the cryopreservation of Hu ram semen.

Adjusting ram semen preservation: Exploring the impact of oxygen exposure during liquid storage.

This study investigated the effects of storage conditions on the quality of chilled ram semen stored at 4°C for 48 h, comparing aerobic and anaerobic conditions. Ejaculates from INRA180 rams were collected and stored under both conditions, with assessments at 0-, 24-, and 48-h intervals. Various sperm parameters were examined, including motility, velocity, viability, morphology, membrane integrity, and lipid peroxidation. Results showed that storage duration significantly impacted sperm quality, leading to a gradual decline from 0 to 24 h and 24 to 48 h. Notably, after the initial 24 h, progressive motility (PM) and membrane integrity (MI) demonstrated distinct responses to storage conditions. Anaerobic storage consistently improved PM and MI values compared to aerobic storage between 24 and 48 h. Anaerobic conditions also enhanced viability and reduced abnormality at the 48-h mark. Total motility remained stable throughout storage. Velocity parameters (VCL: curvilinear velocity; VSL: straight velocity and VAP: velocity average path) exhibited differences between the 24- and 48-h intervals, with anaerobic storage resulting in higher VAP and VSL values. Moreover, lipid peroxidation exhibited a progressive increase from 0 to 24 h and 24 to 48 h, independent of storage conditions. Remarkably, anaerobic storage consistently yielded lower lipid peroxidation levels compared to aerobic storage, regardless of storage duration. In conclusion, this study highlights that the anaerobic storage proved advantageous for chilled ram semen quality, particularly after the initial 24 h.

PERSPECTIVE: Semen additives for improving frozen-thawed buffalo and cattle semen - a review.

This comprehensive review delves into the evolving landscape of assisted reproductive technologies (ARTs) in bovine species, particularly focusing on the pivotal roles of semen additives in the cryopreservation of buffalo and cattle semen. In developing nations, where ARTs are still emerging, these techniques significantly influence bovine reproductive strategies. In contrast, developed regions have embraced them as primary approaches for dairy buffalo and cattle breeding. Semen cryopreservation, while offering advantages like extended storage and genetic propagation, also presents challenges. These include diminished sperm quality due to reactive oxygen species (ROS) production, alterations in sperm structure, and temperature fluctuations. Further, the effect of cryopreservation differs between cattle and buffaloes, with the latter exhibiting poorer semen viability and fertility due to inherent lipid composition susceptibilities. The generation and implications of ROS, especially hydrogen peroxide, contribute significantly to sperm DNA damage and functional impairments. To counteract these challenges, research has intensified on semen additives, aiming to bolster semen quality and protect against oxidative stress-induced damage. As the field advances, the review emphasizes the need for optimized cryopreservation techniques and tailored antioxidant strategies to harness the full potential of ARTs in bovine breeding programs. Doi.org/10.54680/fr24410110112.

Fatty acid composition and biophysical characteristics of the cell membrane of feline spermatozoa.

Sperm membrane composition and biophysical characteristics play a pivotal role in many physiological processes (i.e. sperm motility, capacitation, acrosome reaction and fusion with the oocyte) as well as in semen processing (e.g. cryopreservation). The aim of this study was to characterize the fatty acid content and biophysical characteristics (anisotropy, generalized polarization) of the cell membrane of domestic cat spermatozoa. Semen was collected from 34 adult male cats by urethral catheterization. After a basic semen evaluation, the fatty acid content of some of the samples (n = 11) was evaluated by gas chromatography. Samples from other individuals (n = 23) were subjected to biophysical analysis: membrane anisotropy (which is inversely proportional to membrane fluidity) and generalized polarization (describing lipid order); both measured by fluorimetry at three temperature points: 38 °C, 25 °C and 5 °C. Spermatozoa from some samples (n = 10) were cryopreserved in TRIS egg yolk-glycerol extender and underwent the same biophysical analysis after thawing. Most fatty acids in feline spermatozoa were saturated (69.76 ± 24.45%), whereas the polyunsaturated fatty acid (PUFA) content was relatively low (6.12 ± 5.80%). Lowering the temperature caused a significant decrease in membrane fluidity and an increase in generalized polarization in fresh spermatozoa, and these effects were even more pronounced following cryopreservation. Anisotropy at 38 °C in fresh samples showed strong positive correlations with viability and motility parameters after thawing. In summary, feline spermatozoa are characterized by a very low PUFA content and a low ratio of unsaturated:saturated fatty acids, which may contribute to low oxidative stress. Cryopreservation alters the structure of the sperm membrane, increasing the fluidity of the hydrophobic portion of the bilayer and the lipid order in the hydrophilic portion. Because lower membrane fluidity in fresh semen was linked with better viability and motility after cryopreservation, this parameter may be considered an important factor in determination of sperm cryoresistance.

Subtle membrane changes in cryopreserved bull spermatozoa when modified temperature drop rates are used during the first phase of freezing.

BACKGROUND: Cryopreservation of spermatozoa involves reduction of temperature to a subzero level, leading to increased longevity. However, temperature reduction has a significant effect on sperm membranes. OBJECTIVE: To evaluate the impact of the rate of temperature drop during the first phase of freezing on subtle membrane changes in cryopreserved bull spermatozoa. MATERIALS AND METHODS: Thirty-two ejaculates from four bulls (eight ejaculates/bull) were collected using artificial vagina while keeping a 3 to 4 days gap between two collections. Diluted semen samples were equilibrated at 5 degree C for 4 hours. The samples were then placed in a pre-programmed semen freezer. The first phase of freezing, that is, 5 degree C till -10 degree C was subjected to three different temperature drop rates: accelerated (F1), moderate (F2), and slow (F3), at 20 degree C per min, 10 degree C per min and 5 degree C per min, respectively. After thawing, spermatozoa were assessed for percentage live, plasma, and acrosomal membrane integrity, along with the external appearance of phosphatidyl serine, indicating apoptosis. RESULTS: A significant difference (p < 0.05) in viability, plasma membrane integrity (HOS test), and acrosome membrane integrity (PSA test) was observed between F3 and the other groups. However, the parameters did not significantly differ between F1 and F2. The annexin V-PI assay (AN/PI) categorized four types of sperm populations: non-apoptotic and viable (AN-/PI-), apoptotic and viable (AN+/PI-), non-apoptotic and non-viable (AN-/PI+), and apoptotic and non-viable (AN+/PI+). The proportion of spermatozoa with (AN-/PI-) and (AN+/PI+) differed significantly (p < 0.05) between F3 and the other groups. The values for apoptotic and viable (AN+/PI-) and non-apoptotic and non-viable (AN-/PI+) sperm were not significantly different among all freezing categories. CONCLUSION: A slower temperature drop rate (freezing rate) during the first phase of freezing results in less damaging, subtle membrane changes. Doi.org/10.54680/fr24410110312.

Cryopreservation alters buffalo sperm kinematics and mitochondrial parameters, acrosome and intra-cellular calcium status.

BACKGROUND: Little is known about the effects of different seasons on the cryopreservation success of buffalo sperm in terms of kinematics and sperm functional parameters. OBJECTIVE: To study the effect of three seasons (winter, comfort and summer) and cryopreservation on sperm kinematics and functional properties in buffalo bulls. MATERIALS AND METHODS: Semen ejaculates (n = 90) collected during three seasons i.e. winter (n = 30), comfort (n = 30), summer (n = 30) were evaluated for sperm kinematics and functional properties. RESULTS: Sperm kinematics with respect to total (TM), progressive (PM) and rapid motility (RM) was higher (P < 0.05) in fresh sperm compared to sperm that had been frozen-thawed. Similarly, all kinematic parameters [viz. average path velocity (VAP), straight linear velocity (VSL), curvilinear velocity (VCL), beats cross frequency (BCF), lateral head displacement (ALH), linearity (LIN) and straightness (STR)] were higher (P < 0.01) at the fresh stage. With respect to season, frozen-thawed semen TM (57.67 ± 115 %), PM (50.2 ± 1.15 %) and RM (51.6 ± 1.19 %) were higher (P < 0.01) when using sperm collected during winter. The stage of cryopreservation (i.e., equilibration and freeze-thawing) also showed significant effects (P < 0.01) on mitochondrial superoxide positive status (MSPS), mitochondrial membrane potential (MMP), acrosome status and intra-cellular calcium status. CONCLUSION: The season of sperm collection and cryopreservation have significant effects on buffalo bull sperm kinematics and functional properties. Doi.org/10.54680/fr24410110612.

Pregnancy and neonatal outcomes of ICSI using pentoxifylline to identify viable spermatozoa in patients with frozen-thawed testicular spermatozoa.

Introduction: Although the effectiveness of pentoxifylline (PF) as a selective inhibitor of phosphodiesterase to enhance sperm motility through increasing cyclic nucleotide in cases of absolute asthenozoospermia has been demonstrated for ICSI, data related to babies born from the PF-ICSI are still severely lacking. Concerns have been raised regarding the potential embryotoxicity of PF due to the controversial results obtained from the analysis of this compound on animal embryo development. This study aimed to determine whether the application of PF to trigger frozen-thawed TESA (testicular sperm aspiration) spermatozoa increases the risk of adverse obstetric and neonatal outcomes compared with non-PF frozen-thawed TESA ICSI and conventional ICSI using fresh ejaculation. Materials and methods: A total of 5438 patients were analyzed in this study, including 240 patients underwent PF-TESA ICSI (ICSI using PF triggered frozen-thawed testicular spermatozoa), 101 patients underwent non-PF TESA ICSI (ICSI using frozen-thawed testicular spermatozoa) and 5097 patients underwent conventional ICSI using fresh ejaculation. Propensity score matching was executed to control the various characteristics of patients. Results: No significant differences in pregnancy outcomes were observed among the three groups (PF-TESA ICSI, non-PF TESA ICSI and conventional ICSI), including biochemical pregnancy, clinical pregnancy, implantation, miscarriage, ectopic pregnancy, multiple pregnancy, and live birth, following propensity score matching. Additionally, neonatal outcomes were found to be similar among the three groups, with no statistical differences observed in the birth defect, birth weight, gestational age, preterm birth, and early-neonatal death. Discussion and conclusion: PF-ICSI may be an alternative treatment in patients using frozen-thawed testicular spermatozoa, resulting in comparable pregnancy and neonatal outcomes.

Voltage-dependent anion channels are involved in the maintenance of pig sperm quality during liquid preservation.

Pigs are usually bred through artificial insemination with liquid semen preserved at 15-20 °C. While this method of preservation brings many benefits, including a greater reproductive performance compared to frozen-thawed sperm, the period of storage is a limiting factor. As the mitochondrion regulates many facets of sperm physiology, modulating its activity could have an impact on their lifespan. Aligned with this hypothesis, the present study sought to investigate whether inhibition of voltage-dependent anion channels (VDACs), which reside in the outer mitochondrial membrane and regulate the flux of ions between mitochondria and the cytosol in somatic cells, influences the resilience of pig sperm to liquid preservation at 17 °C. For this purpose, semen samples (N = 7) were treated with two different concentrations of TRO19622 (5 µM and 50 µM), an inhibitor of VDACs, and stored at 17 °C for 10 days. At days 0, 4 and 10, sperm quality and functionality parameters were evaluated by flow cytometry and computer-assisted sperm analysis (CASA). The effects of inhibiting VDACs depended on the concentration of the inhibitor. On the one hand, the greatest concentration of TRO19622 (50 µM) led to a decrease in sperm motility, viability and mitochondrial membrane potential, which could be related to the observed intracellular Ca2+ increase. In contrast, total sperm motility was higher in samples treated with 5 µM TRO19622 than in the control, suggesting that when VDACs channels are inhibited by the lowest concentration of the blocking agent the resilience of pig sperm to liquid storage increases. In conclusion, the current research indicates that mitochondrial function, as regulated by ion channels in the outer mitochondrial membrane like VDACs, is related to the sperm resilience to liquid preservation and may influence cell lifespan.

Recent advances in cryotolerance biomarkers for semen preservation in frozen form-A systematic review.

Spermatozoa cryopreservation has been practiced for decades and is a very useful technique for long-term preservation of sperm fertility. The capability for semen cryopreservation varies across species, seasons, latitudes, and even for different ejaculates from the same animal. This article summarizes research results on sperm cryotolerance biomarkers in several species, focusing on three areas: spermatozoa cryotolerance biomarkers, seminal plasma proteins cryotolerance biomarkers, and other cryotolerance biomarkers. We discovered that sperm cryoresistance biomarkers are primarily related to sperm plasma membrane stability, the presence of antioxidant substances in sperm or seminal plasma, sperm cell energy metabolism, water and small molecule transport channels in the sperm plasma membrane, and antistress substances in sperm or seminal plasma. The research conducted using diverse livestock models can be employed to enhance the basic and applied reproduction of other mammals through the study of sperm cryotolerance biomarkers, as well as the substantial similarities between livestock and other organisms, including endangered species.