Effect of l-arginine addition on long-term storability of ram semen

Changes in fatty acids, vitamins, cholesterol and amino acid profiles of ram semen by freeze-thawing process

The objective of this study was to examine the impact of freeze-thawing on the levels of oxidative stress, fatty acids, vitamins A, D, E, and K, cholesterol, and amino acids, as well as on spermatological parameters, in ram semen. Semen was collected and pooled from each of the seven rams twice a week for three weeks. The mixed semen was diluted with tris + egg yolk diluent at 38 °C (Group 38 °C) and the temperature was reduced to 5 °C (Group 5 °C). Following the glycerolization-equilibration process (Group G-E), the samples were automatically frozen in liquid nitrogen vapor at -140 °C. The semen samples were thawed 24 h after freezing (Group Frozen-Thawed, F-T). A comparison of Group 38 °C with Group F-T revealed significant differences in several parameters. Motility rates, kinematic values, percentage of membrane integrity (HOS), some PUFA levels, ∑SFA and amino acid levels were significantly lower in Group F-T. Conversely, the ratio of dead and static spermatozoa, lipid peroxidation level, some PUFA levels, ∑MUFA, vitamins A, E and cholesterol levels were significantly higher in Group F-T. The majority of these alterations were also evident in semen samples subjected to G-E treatment. In conclusion, exposure of ram semen to G-E and F-T treatments results in modifications to semen, fatty acid, vitamin, and amino acid profiles, accompanied by elevated levels of lipid peroxidation. Moreover, this study demonstrated, for the first time, that oxidative stress was induced, some amino acid levels were altered, vitamin A and E levels were increased, vitamin D and K levels were not affected, and β-sitosterol levels were decreased after freeze-thawing in ram semen.

Effect of selenium nanoparticles-supplemented INRA96 extender on Turkmen stallion sperm quality and lipid peroxidation during storage at 5°C

Oxidative damage to sperm during cooled storage is a significant issue, and selenium with antioxidant potential could be a solution. Moreover, nano-sized selenium offers more advantages compared to its ionic forms. This research aimed to assess the impact of selenium nanoparticles (SeNPs) supplemented in the INRA96 extender on the quality of Turkmen stallion sperm and lipid peroxidation during 72 h of cooled storage. A total of 25 ejaculates were treated using different concentrations of SeNPs, including no SeNPs (Control), 0.5 μM SeNPs (SeNPs 0.5), 1.0 μM SeNPs (SeNPs 1.0), and 1.5 μM SeNPs (SeNPs 1.5). The samples were then evaluated for sperm quality characteristics and lipid peroxidation. The results indicated a significant decrease (P < 0.05) in total and progressive motility, viability, and plasma membrane functionality after 48 h of cooled storage, along with an increase (P < 0.05) in spermatozoa abnormality and malondialdehyde (MDA) levels as the cooled storage time increased. However, SeNPs demonstrated an improvement (P < 0.05) in sperm total motility after 24 h of cooled storage, progressive motility throughout the entire 72-hour period, functionality of the plasma membrane after 48 hours of cooled storage, spermatozoa abnormality after 48 h of cooled storage, and semen MDA levels throughout the cooled storage (P < 0.05). In conclusion, the enrichment of the INRA96 extender with nano-sized selenium can enhance the quality of Turkmen stallion sperm during storage at 5 °C by increasing total, progressive, and curvilinear motilities, improving plasma membrane functionality, and reducing sperm abnormalities and lipid peroxidation.

Reduction of cryopreservation-induced structural, functional and molecular damages in ram sperm by hydrated C60 fullerene

This study aimed to investigate the morphological, functional and molecular changes in frozen-thawed ram sperm using an extender containing different concentrations of hydrated carbon 60 fullerene (C60 HyFn), a nanotechnological product. Semen taken from each of the seven Akkaraman rams were pooled. Semen collection was done twice a week and it continued for 3 weeks. Each pooled semen sample was divided into six equal groups and diluted with tris + egg yolk extender including 0 (control), 200, 400, 800 nM, 1 and 5 μM concentrations of C60 HyFn at 37°C. They were then frozen in liquid nitrogen vapour at -140°C, stored in liquid nitrogen container (-196°C) and thawed at 37°C for 25 s before analysis. In comparison with control, C60 HyFn addition prior to freezing procedure provided significant increases in total and progressive motility rates, glutathione peroxidase, catalase activities and percentage of highly active mitochondria, and significant decreases in dead and abnormal sperm rates, lipid peroxidation, caspase-3 and DNA fragmentation levels in frozen-thawed ram semen. When compared to control, C60 HyFn supplementation significantly down-regulated the expression levels of miR-200a and KCNJ11, and significantly up-regulated the expression levels of miR-3958-3p (at the concentrations of 200, 400, 800 nM and 1 μM), CatSper1 (at the concentrations of 200, 400 nM and 5 μM), CatSper2 (at the concentrations of 1 and 5 μM), CatSper3 (at the concentrations of 200, 400 nM, 1 and 5 μM), CatSper4 (at all concentrations), ANO1 (at the concentrations of 800 nM, 1 and 5 μM) and TRPV5 (at the concentrations of 200, 400 and 800 nM). The addition of C60 HyFn had no effect on global DNA methylation rates. As a result, C60 HyFn supplementation to ram semen extenders may be beneficial in reducing some of the functional, structural and molecular damages in sperm induced by the freeze-thawing procedure.

Recent approaches in the use of antioxidants and proteomic modifications in ram semen preservation

Sperm preservation is a well-established technique in reproductive biotechnology that is widely used to maintain the genetic quality of male individuals. However, there are several factors during the preservation process that can affect the vitality, functionality, and quality of sperm, thereby reducing their fertility potential after thawing. One of these factors is the synthesis of high levels of oxidative stress (OS) during semen preservation, which can have detrimental effects on sperm health and functionality. To counter the negative impact of OS on sperm, researchers have explored the supplementation of several exogenous antioxidants in the extenders used to preserve ram sperm. This approach has shown promising results in improving sperm health, functionality, and fertility potential in ram. Additionally, the preservation process can induce modifications in the ram sperm proteome. By employing targeted proteomics techniques, researchers have been able to identify and modify specific proteins in cryopreserved ram sperm, potentially offering further improvements in the quality of the cryopreserved ram sperm. In summary, this review provides a comprehensive overview of the antioxidants and targeted proteomics modifications that have been investigated for enhancing ram sperm preservation. These advancements aim to mitigate the negative effects of OS and optimize the techniques used in preserving ram sperm.

Targeted Amino Acids Profiling of Human Seminal Plasma from Teratozoospermia Patients Using LC-MS/MS

Identifying the metabolome of human seminal plasma (HSP) is a new research area to screen putative biomarkers of infertility. This case-control study was performed on HSP specimens of 15 infertile patients with teratozoospermia (defined as normal sperm morphology < 4%) and 12 confirmed fertile normozoospermic men as the control group to investigate the seminal metabolic signature and whether there are differences in the metabolome between two groups. HSPs were subjected to LC-MS-MS analysis. MetaboAnalyst5.0 software was utilized for statistical analysis. Different univariate and multivariate analyses were used, including T-tests, fold change analysis, random forest (RF), and metabolite set enrichment analysis (MSEA). Teratozoospermic samples contained seventeen significantly different amino acids. Upregulated metabolites include glutamine, asparagine, and glycylproline, whereas downregulated metabolites include cysteine, γ-aminobutyric acid, histidine, hydroxylysine, hydroxyproline, glycine, proline, methionine, ornithine, tryptophan, aspartic acid, argininosuccinic acid, α-aminoadipic acid, and β-aminoisobutyric acid. RF algorithm defined a set of 15 metabolites that constitute the significant features of teratozoospermia. In particular, increased glutamine, asparagine, and decreased cysteine, tryptophan, glycine, and valine were strong predictors of teratozoospemia. The most affected metabolic pathways in teratozoospermic men are the aminoacyl-tRNA, arginine, valine-leucine, and isoleucine biosynthesis. Altered metabolites detected in teratozoospermia were responsible for various roles in sperm functions that classified into four subgroups as follows: related metabolites to antioxidant function, energy production, sperm function, and spermatogenesis. The altered amino acid metabolome identified in this study may be related to the etiology of teratozoospermia, and may provide novel insight into potential biomarkers of male infertility for therapeutic targets.

Effect of Hydrated Carbon 60 Fullerene on Frozen Ram Semen Quality

The aim of this study was to evaluate the effect of hydrated carbon 60 fullerene (C₆₀HyFn) on ram semen quality during cryopreservation. Three ejaculates from each of seven Akkaraman rams were collected using an artificial vagina during the nonbreeding season and pooled. Pooled semen samples were divided into 10 equal parts and diluted with tris + egg yolk extender not containing (control) and containing 100, 200, 400, and 800 nM and 1, 5, 10, 20, and 40 μM C₆₀HyFn at 37°C. After addition of 5% glycerol and an equilibration process for 3 hours, the samples were frozen in 0.25-mL straws in an automatic freezing device at -140°C and stored in a liquid nitrogen container. Straws were thawed 24 hours after freezing and analyzed immediately with no incubation period. Motility, kinematic parameters, abnormality, vitality, hypo-osmotic swelling test (HOST), and oxidative stress levels were analyzed in thawed semen. Compared with the control, 200, 400, and 800 nM and 1 and 5 μM C₆₀HyFn doses increased motility and HOST values and decreased the dead sperm rate. When compared with the control, addition of C₆₀HyFn significantly decreased malondialdehyde levels (between 200 nM and 40 μM doses) and significantly increased glutathione peroxidase (between 800 nM and 40 μM doses) and catalase (between 1 and 40 μM doses) activities. In conclusion, results of this study show that the C₆₀HyFn nanoparticles are nontoxic to ram semen and their supplementation in the extender is beneficial to sperm motility and membrane integrity after freeze-thawing.

Effect of adding different concentrations of L-arginine to Tris-yolk extender on the quality of sub-fertile ejaculates in buffalo

To investigate the effect of supplementation of L-arginine (AR) on sub-fertile buffalo-bulls' ejaculates, 25 ejaculates of poor motility (40 to 55%) were collected by artificial vagina from 5 buffalo-bulls and extended with Tris-yolk extender (1:10) supplemented with different concentrations of AR (0, 3, 4, 5, and 6 mM). Semen was cooled gradually to 4 °C within 2 h and incubated at 4 °C for additional 2 h. Incubated semen samples were evaluated by computer-assisted semen analysis. Results showed that addition of 5 mM AR increased (P < 0.05) total sperm motility and rapid progressive motility percentages, while decreased (P < 0.05) non-motile sperm and static sperm percentages compared with AR-free (control) extender. Increasing the AR level to 6 mM increased (P < 0.05) the percentages of sperm progressive motility and rapid and slow progressive motilities, while decreased (P < 0.05) the non-progressive sperm motility percentages compared with AR-free extender. Supplementation of 5 mM AR improved (P < 0.05) sperm straight linear, curve linear, and average path velocities (36 ± 0.13, 20.6 ± 5.3, and 33.2 ± 8.5, respectively) in comparing with control and other AR treatments. Addition of AR (5 and 6 mM) improved (P < 0.05) the percentages of vitality (89.8 ± 1.9 and 80.0 ± 3.4, respectively), normality (44.3 ± 3.6 and 44.8 ± 1.5, respectively), and functional sperm (20.4 ± 8.6 and 21.0 ± 0.61, respectively), and decreased abnormal neck and tail percentages compared with AR-free extender. All AR levels decreased (P < 0.05) the abnormal neck and tail percentages. Addition of all AR levels had no significant (P > 0.05) effect on the activity of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in semen extender. Supplementation of Tris-yolk extender with L-arginine (5 or 6 mM) can improve sperm motility, velocity, vitality, and functional sperm and can decrease tail and neck abnormalities of sub-fertile buffalo ejaculate after 4 h incubation at cool temperature.

Addition of L-arginine in skim milk extender maintains goat spermatozoa quality in chilled temperature for five days

Aim:

The purpose of this study was to determine the benefits of L-arginine addition in skim milk extender to maintain the quality of goat spermatozoa in chilled storage.

Materials and Methods:

A total of 18 ejaculates from three healthy goats with weight and age of 45 kg and 4-5 years, respectively, were divided into three groups. The control group contained goat semen diluted in a skim milk extender without L-arginine; Treatment I and Treatment II contained goat semen diluted in a skim milk extender with added L-arginine 4 and 6 mM, respectively. These three groups were chilled at 5°C and evaluated daily for 5 days. Observed variables were viability, motility, intact plasma membrane (IPM), malondialdehyde (MDA) level, necrosis, and apoptosis of spermatozoa.

Results:

The addition of L-arginine 4 mM was the best treatment in maintaining viability, motility, and IPM and a decreased MDA level, percentage of necrosis, and apoptosis of goat spermatozoa. An ejaculate in this extender can be divided into 37 doses for intracervical insemination in <1 ml volume with 125 million motile spermatozoa.

Conclusion:

Goat semen retained its quality when kept for 5 days in chilled storage by adding L-arginine in skim milk extender.

Effect of addition of melatonin on liquid storage of ram semen at 4°C

Adding a certain amount of antioxidants to semen extender has been shown to improve semen quality. The aim of present study was to elucidate whether the supplementation of melatonin to the Tris-based extender (CTR) could enhance the quality of ram spermatozoa during storage at 4°C. Ram semen samples were collected and diluted with CTR extender containing different concentrations (0, 0.05 (M 0.05), 0.1 (M 0.1), 0.2 (M 0.2) or 0.4 (M 0.4) mM) of melatonin. Sperm routine indicators, mitochondrial activity, total antioxidant capacity (T-AOC) and malondialdehyde (MDA) content were analysed in control and melatonin treatment groups. The higher per cent of motility, plasma membrane integrity, mitochondrial activity and T-AOC activity was observed in M 0.05, M 0.1 and M 0.2 groups compared to control group at 5 days of storage (p < 0.05), while lower percentage of MDA content was observed among these groups (p < 0.05). In addition, there were no significant differences in acrosome integrity among the control and M 0.05, M 0.1 and M 0.2 groups during the experiment. The above results show that the addition of 0.05, 0.1, 0.2 mM of melatonin is beneficial to the preservation of ram semen during liquid storage at 4°C mainly through antioxidative stress.