Sperm Oxidative Stress Research Articles

Changes in sperm quality with an antioxidant formula in mild-moderate male infertility: a prospective study

IntroductionThis study aimed to examine for an association between an antioxidant formula and sperm quality as well as safety in males with mild to moderate sub-fertility. MethodsA prospective, open-label single-arm study examined the association between 24 weeks treatment with a proprietary formula containing 15 vitamins, minerals and antioxidants (including L-carnitine, acetyl-L-carnitine, selenium, folic acid, L-cysteine and Co-enzyme Q10) and sperm quality in healthy males aged 20 – 60 with idiopathic teratospermia, asthenospermia and/or mild-moderate oligospermia. The primary outcome was simultaneous change in sperm concentration, progressive motility and morphology between screening, week 16 and week 24. Secondary outcomes included safety, pregnancy rates, sperm oxidative stress, sperm DNA fragmentation, and serum/plasma nutrient levels. ResultsSixty-one participants, with a mean age of 35.8 years, were included in the intention-to-treat analysis. No improvement in overall sperm quality was observed (i.e. simultaneous improvement in all three measures) as only two of the three sperm quality measures improved. Mean sperm concentration decreased by 0.24 standard deviations (SD) while mean morphology and motility improved by 0.28 and 0.04 SD respectively, however, these changes did not reach clinical significance (set at ≥ 0.4 SD improvement in means). There were no changes in secondary outcomes apart from an increase in homocysteine and vitamin B12 levels and decrease in high DNA stainability. Fifteen pregnancies were reported (pregnancy rate 29%). Twenty-one of 62 (33.8%) of participants reported 36 adverse events (AEs), one of which was serious leading to study withdrawal. Most AEs were of mild intensity and resolved. ConclusionTwenty-four weeks of an antioxidant formula was not associated with clinically significant changes in overall sperm quality. The formula was generally safe and well tolerated. Our findings are limited by the single- arm design, and randomised controlled trials are required to confirm or refute our findings.

Reliable Detection of Excessive Sperm Ros Production in Subfertile Patients: How Many Men with Oxidative Stress?

Sperm oxidative stress has been extensively associated to male infertility. However, tests to detect this parameter have not been yet introduced in clinical practice and no definitive data are present on the extent of oxidative stress in male infertility. In this study, we used a novel and reliable flow cytometric method to reveal sperm ROS production in subfertile patients (n = 131) and in healthy donors (n = 31). Oxidative stress was higher in subfertile patients (14.22 [10.21-22.08]%) than in healthy donors (9.75 [8.00-14.90]% (p < 0.01)), but no correlation was found with age, semen quality or sDF. We also failed to detect an increase in sperm ROS production with semen viscosity or leukocytospermia, but a sharp impact of semen bacteria was evident (with bacteria: 31.61 [14.08-46.78]% vs. without bacteria: 14.20 [10.12-22.00]%, p < 0.01). Finally, after establishing a threshold as the 95th percentile in healthy donors, we found that 29% of subfertile patients exceeded this threshold. The percentage decreased to 25.56% when we excluded subjects with bacteriospermia and increased to 60.87% when only these patients were considered. In conclusion, 29% of subfertile patients showed an excessive sperm ROS production. Surprisingly, this parameter appears to be independent from routine semen analysis and even sDF determination, promising to provide additional information on male infertility.

The Association Between Oxidative Stress and Sperm Parameters in Patients with Acromegaly.

Spermatozoa are susceptible to oxidative radicals when antioxidant defenses are inadequate. The extent to which oxidative radicals contribute to sperm damage in patients with acromegaly remains unclear. This study aimed to investigate and elucidate this relationship. The overall status of oxidants and antioxidants in both seminal plasma and serum of patients with acromegaly compared to a control group of healthy individuals was investigated. In addition, sperm parameters, including important measures such as growth hormone and insulin-like growth factor-1 concentrations. Twenty-two patients with acromegaly with controlled disease and 14 healthy controls were included. The total oxidant status was significantly higher in the semen samples of the patients with acromegaly. A negative correlation was found between sperm total oxidant status and total sperm count and sperm concentration. Similarly, a negative correlation was found between the total sperm count and the sperm oxidative stress index. In individuals diagnosed with acromegaly, there was a statistically significant increase in sperm growth hormone levels. Conversely, the level of insulin-like growth factor 1 was significantly increased in the sperm of the control group, which consisted of healthy individuals. The correlation analysis revealed a significant relationship between venous total oxidant status and growth hormone levels in semen. The elevated levels of reactive oxygen radicals in individuals with acromegaly suggest a possible link between oxidative stress and its effects on semen quality.

Silymarin mitigates toxic effects of cyclophosphamide on testicular tissue and sperm parameters in mice

Cyclophosphamide, a chemotherapy drug, increases oxidative stress in sperm and testicular tissue. This study evaluated the effect of silymarin, a potent antioxidant, on the quality of sperm and testicular tissue in mice treated with cyclophosphamide. NMRI adult male mice were divided into four groups: control; cyclophosphamide (intraperitoneal injection, 100 mg/kg, once a week); cyclophosphamide + silymarin; and silymarin (intraperitoneal injection, 200 mg/kg, every other day). After a 35-day treatment period, the caudal region of the epididymis was examined for sperm parameters, the right testis was used for stereological studies, and the left testis was used to assess biochemical factors. The data were statistically analyzed using SPSS software, one-way ANOVA and Tukey's test. In the cyclophosphamide group, there was a significant reduction in the mean total volume of testicular tissue, the average volume of seminiferous tubules and their components, and the average volume of interstitial tissue. Additionally, there was a notable decrease (p < 0.001) in the average number of Leydig cells, Sertoli cells, and sperm parameters. The mean concentration of testosterone hormone (p < 0.05) and total antioxidant capacity (TAC) level (p < 0.01) also significantly decreased, while the malondialdehyde (MDA) level increased significantly (p < 0.05). However, these adverse changes were mitigated in the cyclophosphamide + silymarin group compared to the cyclophosphamide group. Our results showed that silymarin as an antioxidant can mitigate the adverse effects of cyclophosphamide on testicular tissue and sperm parameters.

P-025 Mitochondrial activity in sperm is associated to blastocyst development: a double-donation study

Abstract Study question Do oxidative parameters in sperm affect oocyte fertilization or blastocyst development in double-donation ICSI cycles? Summary answer While intracellular oxidative stress in sperm does not suppose an impact on fertilization or embryo development, mitochondrial activity is related to increased blastocyst development rates What is known already Reactive oxygen species(ROS) are molecules causing a detrimental effect on sperm quality and function, especially when they are imbalanced with respect to the sperm and seminal plasma antioxidant capacity. Previous research have extensively demonstrated that sperm affected by oxidative stress(OS) show reduced fertilizing capacity, and lead to embryos with impaired development after conventional IVF. The role of OS in sperm in the case of ICSI is, however, controversial because many factors may cause a bias. Not only could this explain the inconsistent results reported thus far, but would also support the need of testing healthy donor gametes to reduce variability. Study design, size, duration This research was devised in the context of a collaboration between a sperm bank and a public university, and was set as a blinded, retrospective study that included samples from 45 sperm donors used in a total of 55 oocyte donation cycles. Intracellular levels of total ROS and of superoxides (O2•-), oxidative stress and mitochondrial activity (MA) were evaluated in frozen-thawed sperm donor samples, and related to the embryo outcomes obtained from the same samples. Participants/materials, setting, methods Samples from selected sperm donors were used to fertilize oocytes through ICSI in oocyte donation programs, and fertilization and blastocyst rates were recorded. Sperm viability and intracellular levels of total ROS and superoxides were determined through a combined assay (2’,7’-Dichlorofluorescin diacetate/Hydroethidine/Sytox Red); oxidative stress and sperm viability were assessed through co-staining with CellRox Far Red and propidium iodide (PI); and MA (mitochondrial membrane potential) and sperm viability were evaluated after staining with DiOC6(3) and PI. Main results and the role of chance The average and standard deviation for fertilization and blastocyst rates were 76.8%±17.3% and 67.5%±22.8%, respectively. Taking the viable sperm population into account, percentages of sperm with high ROS and low O2•- were 17.6%±15.9%, those with high ROS and high O2•- were 0.5%±0.4%, percentages of sperm with low ROS and low O2•- were 25.9%±9.2%, and those with low ROS and high O2•- were 54.5%±21.1%. The evaluation of oxidative stress with CellRox revealed that the percentage of viable sperm with high OS was 63.1%±16.5%. Neither intracellular levels of ROS and superoxides, nor oxidative stress in viable sperm were found to be correlated to fertilization or blastocyst rates (P&amp;gt;0.05). In spite of this, the percentage of viable sperm with high MA, which was 20.7%±10.5%, was observed to be positively correlated to blastocyst rates (Rs=0.276; P=0.04). While sperm mitochondria do not participate in further embryo development, a greater mitochondrial activity in post-thawed donor sperm could indicate a healthier sperm function. Mitochondrial activity could, therefore, be used as a predictive biomarker for embryo development. Limitations, reasons for caution The sample size is the main limitation of this study, despite the efforts made to include a high number of sperm donors. Wider implications of the findings Results obtained in the present study show that ICSI evades the detrimental effects of sperm oxidative stress on fertilization and embryo development. Yet, sperm mitochondrial activity could be used as a biomarker to test the ability of a sperm donor to generate healthy embryos that develop up to blastocyst stage. Trial registration number Not applicable

P-082 Use of TetraSOD® in male infertility: double-blind randomized placebo-controlled study

Abstract Study question Can the use of TetraSOD® (microalgae with high content of the antioxidant enzyme superoxide dismutase) improve semen quality and reduce oxidative stress in sperm? Summary answer The use of TetraSOD® reduces the oxidative stress of sperm, increasing the total sperm count in oligozoospermia and reducing the double-stranded DNA sperm fragmentation. What is known already Male factor is present in approximately 50% of the infertile couples, a large number of them of unknown or idiopathic origin. It has been demonstrated that semen quality is deteriorating over time, perhaps as a result of exposure to several environmental factors related with lifestyle that could impact both directly and indirectly on the complex process of spermatogenesis. Some of these bad habits of lifestyle increase the levels of oxidative stress in semen, which is associated with lower sperm concentration and motility. In this scenario, the use of antioxidants can be useful to increase sperm quality. Study design, size, duration Double-blind randomized placebo-controlled clinical study to assess the effect of 250 mg of TetraSOD® (microalgae with high content of the primary antioxidant enzyme superoxide dismutase). Eighty patients with idiopathic infertility showing asthenozoospermia, oligozoospermia or oligoasthenozoospermia were recruited and randomized to receive 250 mg of TetraSOD® (TSOD group) or placebo (Placebo group) for 3 months. Participants/materials, setting, methods Men with asthenozoospermia, oligozoospemia or aligoastenozoospermia and idiopatic infertility were recruited after informed consent signature. Patients were randomized into two groups. TetraSOD® group received 250 mg of TetraSOD®during 3 months, and Placebo group received capsules without TetraSOD® during the same period of time. Seminogram, double-strand sperm DNA fragmentation (COMET assay) and sORP (static oxidation- reduction potential) were studied at baseline (V0) and after 3 months (V3). Main results and the role of chance TetraSOD® consumption for three months elicited a statistically significant increase (Wilcoxon matched-pairs signed rank test; p=0.02) in the average number of sperms per ejaculate (from 17.06 x 106 to 41.94 x 106) in participants displaying oligozoospermia (&amp;lt;39 x 106 sperms) at V0. In contrast, the lower variation in the measured values in the Placebo group was not statistically significant. Regarding sORP, a statistically significant decrease (Wilcoxon matched-pairs signed rank test; p=0.0233) was observed in participants who displayed a value at V0 between 1.34-10. After TetraSOD® consumption, the average changed from 2.96 to 1.91 mv/106 sperm/ml from V0 to V3. However, not statistically significant changes were detected in the Placebo group between sORP values at V0 and V3. Moreover, in relation to double-stranded DNA breaks, a statistically significant decrease (Wilcoxon matched-pairs signed rank test; p=0.01) in the average percentages (from 31.81% to 25.93%) was measured after consumption of TetraSOD® at V3 in participants displaying a compromised redox status (sORP&amp;gt;1.34-10) at V0. No significant changes were found in the Placebo group. Limitations, reasons for caution The study was performed only in one ethnic group, so in future studies other ethnicities should be included. Wider implications of the findings TetraSOD® may improve male fertility because increases the number of sperms per ejaculate in oligozoospermia and reduces double-stranded DNA fragmentation in sperm when individuals display an altered redox status in semen. Such results might be related to the indirect antioxidant effect of TetraSOD®, reducing oxidative stress in seminal fluid. Trial registration number Not applicable

P-167 The sperm parameters in doubling oocytes by the 1st polar body transfer technique: does it matter?

Abstract Study question Does sperm parameters affect the effectiveness of the 1st polar body (PB) transfer in oocytes and embryo doubling? Summary answer Certain sperm conditions affect the transfer technique efficiency. What is known already Previous studies have shown the effectiveness of the 1st polar body (PB) transfer. The technique allows for the modification of donor oocytes to increase the number of cells suitable for fertilization and at the same time preserve the genetic relatedness to the patient. We established that the effectiveness depends on the morphology of the 1stPB. We also showed that the yield of high-quality blastocysts does not depend on whether fresh or thawed donor oocytes are used. But it is also important to understand whether sperm parameters have a significant effect on the performance of the technique. Study design, size, duration The study was performed in the Medical Center IGR from December 2017 to December 2023 and involved 93 patients (mean age 39.7±5.4 years) who underwent the 1st PB transfer and had indicated sperm parameters used for fertilization, including: normozoospermia (NS, n = 43), asthenozoospermia (AS, n = 24), asthenoteratozoospermia (ATS, n = 20), oligozoospermia (OS, n = 5), cryptozoospermia (CS, n = 1). We evaluated the pronuclear scoring, number of embryos on the 3rd and the 5th post-fertilization day, euploidy according to sperm conditions. Participants/materials, setting, methods We used donor oocytes, patients’ oocytes and their 1stPBs obtained from 93 women and their partners sperm with defined parameters in accordance with WHO norms for 2021. The procedure of donor oocyte enucleation and the 1stPBs transfers was carried out using Nikon Ti Eclipse(Japan) inverted microscope, Saturn 3 laser console(UK). Preimplantation genetic testing for aneuploidy was performed using trophectoderm biopsy. Samples were diagnosed using Ion S5(USA). Statistical analysis was carried out using Chi-square test. Main results and the role of chance The total number of donor oocytes modified by the 1stPB of patient’ oocytes was 364, which were distributed as follows by sperm status: NS - 159 oocytes, AS - 103 oocytes, ATS - 77 oocytes, OS - 19 oocytes, and CS - 6 oocytes. The mean age of the female patients according to the groups was similar (39.6±4.9, 39.8±6.2, 40.0±3.8, 37.8±6.1,40, respectively). The number of 2PN pattern during pronuclear scoring was distributed among groups (NS:AS:ATS:OS:CS) with the following percentages 69.2:65.1:62.3:73.7:66.7, respectively. Among the developing embryos on the 3rdday the distribution was 46.6:46.5:36.4:57.9, respectively. No viable embryos were formed in the CS group, so the group was not included in further calculations. Statistically significant difference (SSD) was not found between the groups on the above-mentioned stages of development (p0.05). On the 5thday the number of developing embryos (percents) was distributed as follows: 23.3:28.2:11.7:31.6 for NS:AS:ATS:OS, respectively. It is worth noting that SSD was found between NS and ATS, OS and ATS groups (p &amp;lt; 0.05) and AS and ATS groups (p &amp;lt; 0.001). Percentage of euploid embryos relative to the number of examined blastocysts from groups NS:AS:ATS was 30.8:23.1:22.2, respectively, SSD wasn’t found between the groups(p &amp;gt; 0.05). Limitations, reasons for caution To increase performance of the 1st PB transfer technique it is also worth considering such parameters as sperm DNA fragmentation and level of sperm oxidative stress, which reflect the chromatin state of the male gamete. Wider implications of the findings The study showed that among patients with asthenoteratozoospermia, the yield of viable embryos was significantly lower compared to the other sperm conditions studied. This fact must be taken into account when predicting the result of using the 1st PB transfer technique. Trial registration number N/A

Assessing the efficacy of a novel sperm-washing medium enriched with serotonin, L-carnitine, and coenzyme Q10: an observational cohort study.

This observational cohort study investigated the potential of a novel sperm-washing medium (SWM) enriched with serotonin (5-HT), L-carnitine (L-C), and coenzyme Q10 (CoQ10) to enhance sperm motility and reduce DNA damage. It compared this innovative medium (5-HT/L-C/CoQ10 SWM) with two widely used commercial media (SWM 1 and SWM 2). Ninety-eight volunteers from an infertility clinic provided semen samples, which were divided into three aliquots for analysis in different SWMs: group 1, SWM was composed of hydroxyethyl piperazineethanesulfonic acid (HEPES), sodium bicarbonate, human serum albumin (HSA), taurine, and gentamicin sulfate (SWM 1); group 2, SWM was composed of HEPES, sodium bicarbonate, and HSA (SWM 2); and group 3, SWM was composed of HEPES-buffered human tubal fluid supplemented with 5-HT, L-C, and CoQ10 (5-HT/L-C/CoQ10 SWM). Sperm motility was categorized as progressive, nonprogressive, or immotile. Apoptosis, reactive oxygen species (ROS) production, and DNA fragmentation were also assessed. There were no significant differences in total or progressive sperm motility among the groups. Spermatozoa in group 3 exhibited reduced apoptosis, necrosis, and ROS levels and increased viability. No significant differences were observed in the DNA fragmentation index among groups. The 5-HT/L-C/CoQ10 SWM reduced sperm oxidative stress and apoptosis compared with those of the two commercially available SWMs, suggesting that 5-HT/L-C/CoQ10 SWM could be useful for enhancing in vitro fertilization success rates.

Evaluation of the relationships between oxidative stress, inflammation, hormonal status and sperm parameters in rats: Canonical correlation analysis

Many endocrine or non-endocrine factors are involved in sperm production. Although reproductive hormones are very important for the initiation and maintenance of spermatogenesis, other factors, such as inflammation and oxidative stress, affect spermatogenesis. The aim of this study is to evaluate the relationships between sperm parameters and hormones, oxidative stress, and inflammation status. We conducted this study on 40 rats. Sperm parameters (motility, abnormal sperm rate, and dead sperm rate), oxidative stress (malondialdehyde, glutathione, glutathione peroxidase, and catalase), inflammation (NF-κβ, TNF-α, IL-1β, IL-6, and IL-10), and hormone parameters (follicle-stimulating hormone, luteinizing hormone, testosterone, melatonin, and corticosterone) were determined. Relationships between mentioned parameters were investigated by canonical correlation analysis. Canonical correlation coefficients for these data sets (sperm-oxidative stress, sperm-inflammation, and sperm-hormone parameters) were found to be strongly significant (rc= 0.875, p<0.001; rc= 0.868, p<0.001; rc= 0.886, p<0.001, respectively). The rate of explanation of oxidative stress, inflammation parameters and hormones by sperm parameters was 61.80 %, 56.10 % and 63.90 %, respectively. Canonical correlation analysis results have revealed that dead sperm rate is mostly related to nuclear factor-kappa beta (NF-κβ), catalase, and corticosterone. CCA, which has taken into account the multiple relationships, has revealed that multidimensional evaluation of data sets can provide important and innovative information to researchers for the assessment of relationships between sperm, oxidative stress, inflammation, and hormone parameters.

Micronutrient Antioxidants for Men (Menevit®) Improve Sperm Function by Reducing Oxidative Stress, Resulting in Improved Assisted Reproductive Technology Outcomes.

Oxidative stress (OS) affects men's health and impairs spermatogenesis. Micronutrient antioxidants are available for male infertility as complemental support; however, their efficacy remains debatable. This study aimed to investigate whether antioxidants can help to reduce sperm OS and improve semen analysis and quality. We included 171 male partners of couples planning to undergo assisted reproductive technology (ART). Male partners, aged 29-41 years, of couples intending to conceive were self-selected to take daily antioxidants (n = 84) containing folic acid and zinc, or not to take antioxidants (n = 52) for 6 months. We analyzed the alterations in serum oxidant levels, sperm parameters, OS, and deoxyribonucleic acid fragmentation after 3 and 6 months. Additionally, implantation, clinical pregnancy, and miscarriage rates after vitrified-warmed embryo transfer were compared between those taking antioxidants and those not taking them after 6 months. In men with high static oxidation-reduction potential (sORP), we observed a significant improvement in sperm concentration and sORP. The high-quality blastocyst rate tended to increase, and implantation and clinical pregnancy rates also significantly increased after 6 months of intervention. The micronutrient antioxidants could improve sperm function by reducing OS and improving ART outcomes. Therefore, micronutrient antioxidants may be a viable treatment option for male infertility.

Alpha-lipoic acid improves the quality of ram spermatozoa stored at 4°C by reducing oxidative stress and increasing mitochondrial potential.

Ram spermatozoa inevitably produce a large number of reactive oxygen species (ROS) during liquid storage, leading to oxidative stress and a decline of spermatozoa quality. Therefore, it is particularly important to add exogenous antioxidants during the process of semen liquid preservation. The purpose of this study is to investigate whether adding alpha-lipoic acid (ALA) to ram semen can reduce oxidative stress and enhance spermatozoa quality during the liquid storage at 4°C. Different concentrations of ALA (0, 0.025, 0.05, 0.1, 0.5, 1 mM) were added to semen and stored at 4°C. During storage at 4°C, spermatozoa motility, kinetic parameters, membrane integrity, acrosome integrity, energy metabolism parameters (mitochondrial membrane potential (ΔΨM) and adenosine triphosphate (ATP)) and oxidative stress parameters [ROS, malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD)] were assessed. The results indicated that 0.1 mM ALA significantly (p<0.05) improved spermatozoa total motility (TM) and progressive motility (PM), plasma membrane integrity, acrosome integrity, ΔΨM, ATP, TAC, and SOD, while significantly (p<0.05) reducing spermatozoa ROS and MDA content compared to the control group. In conclusion, ALA can reduce damage caused by oxidative stress in spermatozoa and effectively improve the quality of semen preserved at 4°C. And the optimal concentration is 0.1 mM.

Oxidative stress affects sperm health and fertility-Time to apply facts learned at the bench to help the patient: Lessons for busy clinicians.

Increased oxidative stress (OS), resulting from the delicate balance between reactive oxygen species (ROS) production and antioxidant defense, is closely linked to sperm abnormalities and male subfertility. Elevated ROS levels particularly affect sperm quality. The vulnerability of spermatozoa to ROS is due to the absence of DNA repair mechanisms and the high presence of polyunsaturated fatty acids in their membranes. This article updates and advances our understanding of the molecular damage caused by OS in spermatozoa, including lipid peroxidation, DNA damage, motility, and functionality. Additionally, the review discusses the challenges in diagnosing OS in semen and recommends accurate and sensitive testing methods. Case studies are utilized to demonstrate the effective management of male infertility caused by OS. Highlighting the need to bridge the gap between research and clinical practice, this review suggests strategies for clinicians, such as lifestyle and dietary changes and antioxidant therapies. The review emphasizes lifestyle modifications and personalized care as effective strategies in managing male infertility caused by OS. This review calls for early detection and intervention and interdisciplinary collaboration to improve patient care in male infertility cases related to increased OS.

In vitro Effects of Olive Leaf Extract (Oleuropein) on Human Sperm Parameters and Oxidative Stress Induced by Bacterial Lipopolysaccharide (LPS).

Recently, biomolecules from natural products have paved the way for novel drug in the treatment of some diseases in vitro and in vivo models as diabetes, cancer and infertility. As such, we aimed to evaluate the capacity of Oleuropein (OLE), the major bio-phenol in olive leaf, to protect human sperm against bacterial lipopolysaccharide (LPS) inducing sperm oxidative stress and defective sperm functions. The toxic effect of OLE on human sperm was firstly investigated by evaluating sperm parameters after incubation during 60 minutes with different concentrations. Determined non-toxic concentration was then used to evaluate the capacity of OLE to protect sperm against LPS oxidative damages and sperm parameters alterations. Thus, sperms were consecutively incubated with LPS (10 µg/mL) and OLE (40 µg/mL) during 60 minutes, then submitted to sperm parameters analysis and oxidative stress assessment by measuring malondialdehyde (MDA), carbonyl groups (CG) levels and the activity of some antioxidant enzymes: superoxide dismutase (SOD) and catalase (CAT). A significant decrease of sperm parameters as well as a significant increase in MDA levels, CG levels, SOD and CAT activities was found after stimulation by LPS. However, a non-significant difference was shown comparing sperms treated by LPS and OLE with LPS-treated control sperms. Consequently, despite the high antioxidant and anti-inflammatory capacity of OLE reported in diverse cells, this phenolic compound seems to be not appropriate to protect human sperm in vitro against induced LPS oxidative stress and seems to have a "double-edged sword" behavior.

Antioxidants positively regulate obesity dependent circRNAs - sperm quality - functional axis.

Obesity is a pathophysiological condition, dependent on body fat accumulation, that progressively induces systemic oxidative stress/inflammation leading to a set of associated clinical manifestations, including male infertility. CircRNAs, covalently closed RNA molecules, are key regulators of sperm quality. Recently, we have characterized a complete profile of high-fat diet (HFD) spermatic circRNA cargo, predicting paternal circRNA dependent networks (ceRNETs), potentially involved in sperm oxidative stress and motility anomalies. In the current work, using HFD C57BL6/J male mice, orally treated with a mix of bioactive molecules (vitamin C; vitamin B12; vitamin E; selenium-L-methionine; glutathione-GSH) for 4 weeks, a reversion of HFD phenotype was observed. In addition, the functional action of the proposed formulations on circRNA biogenesis was evaluated by assessing the endogenous spermatic FUS-dependent backsplicing machinery and related circRNA cargo. After that, spermatic viability and motility were also analyzed. Paternal ceRNETs, potentially involved in oxidative stress regulation and sperm motility defects, were identified and used to suggest that the beneficial action of the food supplements here conveniently formulated on sperm motility was likely due to the recovery of circRNA profile. Such a hypothesis was, then, verified by an in vitro assay.

The role of the transsulfuration pathway in spermatogenesis of vitamin D deficient mice

Vitamin D deficiency is a global health problem and has been linked to defective spermatogenesis and male infertility. In this study, we aimed to investigate the main enzymes involved in the transsulfuration pathway of 1-carbon metabolism, and spermatogenesis function. Therefore, sixteen male C57 mice were addressed to a control (standard diet) or vitamin D deficient (VDD) diet for 14 weeks. The results show that compared to the standard diet, VDD increased final body weight and reduced sperm quality, caused damage to the testicular structure, and decreased the serum levels of testosterone. In addition, serum concentrations of homocysteine, vitamin B12, and sperm oxidative stress markers increased. In testicular tissues, the CBS and CSE protein levels were down-regulated whereas HO-1 was up-regulated at both mRNA and protein expression levels. Within a mice deprivation model, VDD deeply suppressed testosterone and impaired spermatogenesis with oxidative stress-mediated mechanisms. The effects of the deprivation appeared to be at least in part independent of genomic and receptor-mediated vitamin D actions and suggest a specific impairment of the alternative transsulfuration pathway.

Minimizing sperm oxidative stress using nanotechnology for breeding programs in rams

BackgroundArtificial insemination (AI) is a routine breeding technology in animal reproduction. Nevertheless, the temperature-sensitive nature and short fertile lifespan of ram sperm samples hamper its use in AI. In this sense, nanotechnology is an interesting tool to improve sperm protection due to the development of nanomaterials for AI, which could be used as delivery vehicles. In this work, we explored the feasibility of vitamin E nanoemulsion (NE) for improving sperm quality during transport.ResultsWith the aim of evaluating this proposal, ejaculates of 7 mature rams of Manchega breed were collected by artificial vagina and extended to 60 × 106 spz/mL in Andromed®. Samples containing control and NE (12 mmol/L) with and without exogenous oxidative stress (100 µmol/L Fe2+/ascorbate) were stored at 22 and 15 ºC and motility (CASA), viability (YO-PRO/PI), acrosomal integrity (PNA-FITC/PI), mitochondrial membrane potential (Mitotracker Deep Red 633), lipoperoxidation (C11 BODIPY 581/591), intracellular reactive oxygen species (ROS) production and DNA status (SCSA®) monitored during 96 h. Our results show that NE could be used to maintain ram spermatozoa during transport at 15 and 22 ºC for up to 96 h, with no appreciable loss of kinematic and physiological characteristics of freshly collected samples.ConclusionsThe storage of ram spermatozoa in liquid form for 2–5 d with vitamin E nanoemulsions may lead more flexibility to breeders in AI programs. In view of the potential and high versatility of these nanodevices, further studies are being carried out to assess the proposed sperm preservation medium on fertility after artificial insemination.Graphical

Mito-Tempo improves acrosome integrity of frozen-thawed epididymal spermatozoa in tomcats.

In tomcats, epididymal spermatozoa provide an additional source of male gametes available for cryopreservation. While this procedure is feasible, the survival rate and motility of epididymal cat spermatozoa are both low after thawing. Cryopreservation is known to induce oxidative stress in spermatozoa, with mitochondria and the plasma membrane being the two major generation sites, and an imbalanced presence of free radicals is a possible cause for this low survival rate. Different antioxidants have been tested before for their effect on cryopreserved cat spermatozoa quality, with varying results. Here, we used Mito-Tempo, which is a synthetic mitochondria-targeted antioxidant and a specific scavenger of the mitochondrial superoxide system. By supplementing Mito-Tempo with the freezing extender, we aimed to improve the sperm quality of frozen-thawed cat epididymal spermatozoa. Epididymal spermatozoa obtained from twelve tomcats were assessed for motility and concentration. Prior to freezing, samples were diluted in TRIS buffered extender with egg yolk and glycerol and divided into five aliquots supplemented with 0 (control), 0.5, 5, 50, and 1005M of Mito-Tempo. After thawing, sperm motility, concentration, morphology, plasma membrane integrity, acrosome integrity, and mitochondrial membrane potential were evaluated. A Friedman rank sum test with a Bonferroni post-hoc test was used to determine statistical in-between group differences in post-thaw semen parameters. The results indicated a slight improvement in acrosome integrity across all groups that were supplemented with Mito-Tempo, with the group that received 55M of Mito-Tempo showing the greatest improvement [(median of 67.99%, IQR of 5.55) compared to the control group (median of 65.33%, IQR of 7.75; P = 0.05)]. For all other sperm parameters, no significant differences (P > 0.05) were detected between different Mito-Tempo concentrations. These findings highlight the protective effect of Mito-Tempo on acrosome integrity and suggest that 55M is the most effective concentration for maintaining acrosome integrity. Since Mito-Tempo has shown a positive effect on multiple sperm parameters in other species, such as men, boars, roosters, rams, and bulls, we need to conclude that species-specificity may play a role here.

Testicular and Haematological Cancer Induce Very High Levels of Sperm Oxidative Stress.

Cancer impairs spermatogenesis, whereas results on sperm DNA integrity are controversial and no data are available about sperm oxidative stress. In cancer patients, we detected sperm DNA fragmentation (sDF) and both viable (ROS production in viable sperm fraction/viable spermatozoa) and total (ROS production in viable sperm fraction/total spermatozoa) oxidative stress. We found that cancer (22.50 (17.00-26.75)%, n = 85) increased sDF with respect to the control groups in both normozoospermic subfertile patients (NSP) (12.75 (8.63-14.88)%, n = 52, p < 0.001) and in healthy donors (HD) (8.50 (7.00-14.00)%, n = 19, p < 0.001). The induction of viable oxidative stress (n = 96) with cancer was even higher: 36.60 (24.05-58.65)% versus 11.10 (8.63-14.90)% in NSP (p < 0.001) and 9.60 (8.00-14.03)% in HD (p < 0.001). Similar, albeit lower, differences were found for total oxidative stress. SDF sharply correlated to viable oxidative stress when we considered all subjects (cancer patients and controls) (r = 0.591, p < 0.001, n = 134), but no correlation was found when only cancer patients were studied (r = 0.200; p > 0.05, n = 63). In conclusion, cancer significantly increases sDF and sperm oxidative stress levels. Additional mechanisms to oxidative attack might be responsible for increased sDF in cancer patients. Because sperm oxidative stress might affect the outcomes of sperm cryopreservation, of cancer treatments and of sperm epigenoma, the detection of oxidative stress could be of help in managing the reproductive issues of cancer patients.

Effect of saponin on spermatogenesis and testicular structure in streptozotocin-induced diabetic mice.

About a third of human infertility is related to male factors. Of these, idiopathic-related infertility is not curable. Diabetes mellitus is a metabolic disorder affecting male impotence and fertility by increased production of free radicals and oxidative stress. Saponin, a glycosidic compound found in many plants, improves sperm parameters. The present study investigated the effect of saponin on sperm oxidative stress and testicular structure in streptozotocin (STZ)-induced diabetic mice. The diabetes was induced by the administration of 150 mg kg-1 STZ via a single intra-peritoneal injection. All experimental mice were allocated to the following groups: Control group, diabetic control group, diabetic group administrated 100 mg kg-1 saponin daily and one healthy group administrated saponin daily for 56 days. At the end of the treatment period, serum levels of insulin, glucose and oxidative stress markers were measured. A histological evaluation of testicles was performed. Treatment of diabetic mice with saponin ameliorated testicular tissue damage as well as serum glucose and insulin concentrations. Furthermore, in the diabetic group, the serum concentration of malondialdehyde was increased; while, the activity of superoxide dismutase and glutathione peroxidase enzymes was reduced. The mean Johnsen's score and the diameter and thickness of seminiferous tubules were lower in the diabetic mice than control ones. However, these parameters were higher in the saponin-treated mice than controls. Overall, saponin administration rectified all examined parameters. The anti-oxidant role of saponin improves sperm parameters and diabetes-induced testicular oxidative damage.

MiOXSYS® and OxiSperm® II assays appear to provide no clinical utility for determining oxidative stress in human sperm-results from repeated semen collections.

Oxidative stress in semen contributes up to 80% of all infertility diagnosis. Diagnostics to measure oxidative stress in semen was recently added to the 6th edition WHO methods manual, although diagnostic predictive values need to be interpreted with caution as there are still several research questions yet to be answered. To determine the natural fluctuations in semen redox indicators (MiOXSYS® and OxiSperm® II) within and between men and their association with markers of sperm oxidative stress. Total, 118 repeat semen samples from 31 generally healthy men aged 18-45 years, over 6 months. Standard semen analysis as per 5th WHO manual. Semen redox levels measured via MiOXSYS® and OxiSperm® II. Additional attributes of sperm quality; HBA® binding assay and sperm hyperactivation and oxidative stress; DNA fragmentation (Halo® Sperm) and lipid peroxidation (BODIPY™ 581/591 C11) were assessed. Samples with high redox-potential (MiOXSYS® ≥1.47 sORP/106 sperm/ml) had lower sperm, motility, morphology and higher DNA fragmentation (P<0.05). Upon further analysis, these associations were driven solely by the adjustment of sperm concentration (106 /ml) in normalised redox-potential. No significant associations between NBT-reactivity (OxiSperm® II) and measures of the sperm function or oxidative stress were observed (P>0.05). Fluctuations in semen redox levels varied greater between men than within men over the study period. Neither MiOXSYS® nor OxiSperm® II assays were predictive of sperm function or sperm oxidative stress. This was likely due at least in part to limited understanding of their biochemistry and clinical application. As a result, these assays seem to provide no additional clinical utility beyond that of a standard semen analysis, highlighting the imperative for the development of new robust point-of-care devices for accurately determining sperm oxidative stress. These findings suggest that MiOXSYS® and OxiSperm® II systems for the measurement of sperm oxidative stress may have limited diagnostic potential.