A multicenter study to evaluate oxidative stress by oxidation-reduction potential, a reliable and reproducible method

Semen static oxidation-reduction potential is not helpful in evaluating male fertility

BACKGROUND

Infertility affects a significant percentage of couples worldwide, with male infertility contributing substantially in a considerable number of cases. Research indicates that oxidative stress is a critical factor impacting male fertility.

OBJECTIVE

To explore the relationship between semen static oxidation-reduction potential (sORP), sperm parameters, and validated biomarkers of oxidative stress in infertile men.

MATERIALS AND METHODS

This cross-sectional study involved 202 men diagnosed with idiopathic male factor infertility and male partners from couples with unexplained infertility. Multivariable linear regression to query the associations between sORP, sperm parameters, and oxidative aggression biomarkers (lipid peroxidation, mitochondrial membrane potential, annexin V, and sperm DNA fragmentation).

RESULTS

SORP has no linear association with any semen analysis parameter. Furthermore, its relationship with validated biomarkers of oxidative stress was inconsistent. sORP was inversely related to lipid peroxidation (multivariable linear regression coefficient: -0.64), positively associated with sperm DNA fragmentation (multivariable linear regression coefficient: 3.20), and unrelated to mitochondrial membrane potential or annexin V.

CONCLUSIONS

There is no clear or consistent relationship between sORP and validated oxidative aggression biomarkers or sperm parameters. Our findings suggest that sORP is unlikely to be helpful in the evaluation of a male with idiopathic infertility.

A probiotic Limosilactobacillus fermentum GR-3 mitigates colitis-associated tumorigenesis in mice via modulating gut microbiome

Bacterial therapy for colorectal cancer (CRC) represents a burgeoning frontier. The probiotic Limosilactobacillus fermentum GR-3, derived from traditional food "Jiangshui", exhibited superior antioxidant capacity by producing indole derivatives ICA and IPA. In an AOM/DSS-induced CRC mouse model, GR-3 treatment alleviated weight loss, colon shortening, rectal bleeding and intestinal barrier disruption by reducing oxidative stress and inflammation. GR-3 colonization in distant colon induced apoptosis and reduced tumor incidence by 51.2%, outperforming the control strain and vitamin C. The beneficial effect of GR-3 on CRC was associated with gut microbiome modulation, increasing SCFA producer Lachnospiraceae NK4A136 group and suppressing pro-inflammatory strain Bacteroides. Metagenomic and metabolic analyses revealed that GR-3 intervention upregulated antioxidant genes (xseA, ALDH) and butyrate synthesis gene (bcd), while increasing beneficial metabolites (SCFAs, ICA, IPA, VB12 and VD3) and reducing harmful secondary bile acids. Overall, GR-3 emerges as a promising candidate in CRC therapy, offering effective gut microbiome remediation.

Impact of body mass index on semen parameters and reproductive hormones among men undergoing microsurgical subinguinal varicocelectomy

Background

Few studies assessed the relationships between BMI and post varicocelectomy semen quality and fertility potential and they reported inconsistent findings.

Objective

To assess the association of BMI with semen parameters and reproductive hormones before and after microsurgical varicocelectomy.

Materials and Methods

Retrospective chart review in a tertiary infertility center. Of 1170 patients with clinical varicocele during the study period (8 years), 813 patients were eligible and included. Patients were grouped into: Group A (kg/m2, n = 251 patients), B (BMI 25-29.9 kg/m2, n = 289), C (BMI 30-34.9 kg/m2, n = 183) and D (kg/m2, n = 90). Clinical data, semen parameters, sperm DNA fragmentation and hormonal profile were collected before and 3 months after microsurgical varicocelectomy.

Results

Patients' mean age was 35.87 ± 8.17 years. Higher-grade varicocele was significantly more prevalent in the lower BMI groups. BMI was significantly negatively correlated with preoperative sperm concentration, total motility progressive motility and total motile sperm count. Pre-operatively, sperm concentration, total motility, progressive motility and total motile sperm count showed significant differences between BMI groups, where higher BMI (Groups C and D) exhibited the poorest semen parameters. Postoperatively, all groups showed significant improvement in sperm concentration compared with pre-operative values. However, total and progressive motility were significantly improved in Groups A, B and C, while in Group D (highest BMI), total motility improved clinically but not statistically, progressive motility did not display improvement, and total motile sperm count was significantly improved only in Groups B and C. Postoperatively, mean improvements in semen parameters across the BMI groups were not significantly different, except for morphology, which improved significantly more in the less obese patients.

Conclusion

For infertile patients with clinical varicocele undergoing micro-surgical varicocelectomy, BMI appears not to impact the improvements across most of the semen parameters and hormones. The procedure might improve the fertility potential.

In Vitro Nano-Polystyrene Toxicity: Metabolic Dysfunctions and Cytoprotective Responses of Human Spermatozoa

The ubiquitous spread of Polystyrene nanoplastics (PS-NPs) has rendered chronic human exposure an unavoidable phenomenon. The biodistribution of such particles leads to bioaccumulation in target organs including the testis, the site of sperm maturation. The purpose of this research has been to estimate the impact of PS-NPs (50 and 100 nm) on the metabolism of mature spermatozoa. The analysis of the semen parameters has revealed a higher toxicity of the smaller sized PS-NPs, which have negatively affected major organelles, leading to increased acrosomal damage, oxidative stress with the production of ROS, DNA fragmentation, and decreased mitochondrial activity. PS-NPs of 100 nm, on the other hand, have mainly affected the acrosome and induced a general state of stress. An attempt has also been made to highlight possible protective mechanisms such as the expression of HSP70s and their correlation among various parameters. The results have evinced a marked production of HSP70s in the samples exposed to the smaller PS-NPs, negatively correlated with the worsening in oxidative stress, DNA fragmentation, and mitochondrial anomalies. In conclusion, our results have confirmed the toxicity of PS-NPs on human spermatozoa but have also demonstrated the presence of mechanisms capable of counteracting at least in part these injuries.

Eliminating xenobiotics organic compounds from greywater through green synthetic nanoparticles

Xenobiotic Organic Compounds (XOCs) have been widely considered to be pollutant compounds due to their harmful impacts on aquatic life. However, there have been few rigorous studies of cutting-edge technology used to eradicate XOCs and their presence in bathroom greywater. The present review provides a comprehensive examination of current methodologies used for removing XOCs by photocatalysis of green nanoparticles. It was appeared that zinc oxide nanoparticles (ZnO NPs) have high efficiency (99%) in photocatalysis process. Green synthesis provides proven processes that do not require dangerous chemicals or expensive equipment, making photocatalysis a potential solution for the status quo. XOCs residue was decomposed, and pollutants were eliminated with varied degrees of efficiency using green synthesis ZnO nanoparticles. It is hypothesized that the utilization of photocatalysis can create a greywater treatment system capable of degrading the toxic XOCs in greywater while increasing the pace of production. Hence, this review will be beneficial in improving greywater quality and photocatalysis using green nanoparticles can be an immediate platform in solving the issue regarding the existence of XOCs in greywater in Malaysia. Researchers in the future may benefit from focusing on optimizing photocatalytic degradation using green-synthesis ZnO. It might also help with the creativity and productivity of the next generation of authoritative concerns, notably water conservation.

The Sixth Edition of the WHO Manual for Human Semen Analysis: A Critical Review and SWOT Analysis

Semen analysis is the cornerstone of male fertility evaluation with WHO guidelines providing the basis for procedural standardization and reference values worldwide. The first WHO manual was published in 1980, and five editions have been subsequently released over the last four decades. The 6th Edition was published in July 2021. In this review, we identify the key changes of this 6th Edition. Additionally, we evaluate the utility of this 6th Edition in clinical practice using SWOT (strengths, weaknesses, opportunities, and threats) analysis. This new Edition has made the analysis of basic semen parameters more robust, taking into account the criticisms and grey areas of the previous editions. The tests assessing sperm DNA fragmentation and seminal oxidative stress are well-described. The main novelty is that this latest edition abandons the notion of reference thresholds, suggesting instead to replace them with “decision limits”. While this seems attractive, no decision limits are proposed for either basic semen parameters, or for extended or advanced parameters. This critical review of the 6th Edition of the WHO laboratory manual combined with a SWOT analysis summarizes the changes and novelties present in this new Edition and provides an in-depth analysis that could help its global use in the coming years.

Effect of curcumin, and nano-curcumin on sperm function in varicocele rat model

Varicocele is one of the most important causes of infertility in men which gradually leads to testicular dysfunction. Testicular heat stress-induced oxidative stress is considered the main cause of pathology in these individuals. In this study, the effects of curcumin and nano-curcumin, as natural antioxidants, were investigated on spermatogenesis and sperm function in varicocele-induced rats. Seventy Wistar rats were randomly divided into seven groups; sham, control, varicocele, varicocele + curcumin 50 mg, varicocele + curcumin 100 mg, varicocele + nano-curcumin 4 mg and varicocele + nano-curcumin 8 mg. After 2 months of antioxidant therapy, all the rats were sacrificed. The results demonstrated that the mean sperm concentration and motility were significantly lower while the mean of abnormal morphology, lipid peroxidation, intracytoplasmic ROS and DNA damage was significantly higher in varicocelised rats compared to control and sham groups (p < .05). Both doses of curcumin and also nano-curcumin were significantly effective in improving the aforementioned parameters except for abnormal sperm morphology, and motility where nano-curcumin (4 mg) was significantly more effective than other groups (p < .05). The results of the current study suggest the application of nano-curcumin is more preferable to curcumin in infertile individuals with varicocele.

Male subfertility and oxidative stress

To date 15% of couples are suffering from infertility with 45-50% of males being responsible. With an increase in paternal age as well as various environmental and lifestyle factors worsening these figures are expected to increase. As the so-called free radical theory of infertility suggests, free radicals or reactive oxygen species (ROS) play an essential role in this process. However, ROS also fulfill important functions for instance in sperm maturation. The aim of this review article is to discuss the role reactive oxygen species play in male fertility and how these are influenced by lifestyle, age or disease. We will further discuss how these ROS are measured and how they can be avoided during in-vitro fertilization.

Correlation of oxidation reduction potential and total motile sperm count: its utility in the evaluation of male fertility potential

Oxidative stress (OS) is detrimental to sperm functions, and the oxidation reduction potential (ORP) is a good measure of OS as it considers the balance between oxidants and reductants. Total motile sperm count (TMSC) is viewed as the single most important semen analysis parameter that can predict male infertility severity, and its correlation with ORP has never been undertaken. The objectives of this study were to assess the correlation between ORP and TMSC, to identify the ORP cutoff value based on the TMSC result, and to compare this cutoff value with previously reported ORP cutoff values in literature. One thousand one hundred and sixty-eight infertile patients and 100 fertile controls were enrolled. Demographic and semen data of the participants were retrieved and analyzed. Wilcoxon's rank-sum test compared variables between infertile men and fertile controls; Spearman's correlation assessed the static ORP (sORP)-TMSC relationship for the whole sample and among each group individually. Using a 20×10⁶ TMSC threshold, receiver operator characteristic (ROC) analysis determined the sORP cutoff associated with the highest predictive values. TMSC was significantly negatively correlated with sORP across all participants (r = 0.86, P < 0.001), among infertile patients (r = 0.729, P < 0.001), and among fertile controls (r = 0.53, P < 0.001). A 20-million TMSC threshold determined an sORP cutoff value of 2.34 mV/10⁶ sperm/ml to be associated with 82.9% sensitivity, 82.8% specificity, 91.5% positive predictive value (PPV), 68.5% negative predictive value (NPV), and 82.9% overall accuracy. Compared with previously reported cutoff values in searched literature, the 2.34 mV/10⁶ sperm/ml cutoff value identified in our study yielded the highest overall diagnostic accuracy in the evaluation of infertile men.

Coenzyme Q10, oxidative stress, and male infertility: A review

Male infertility has a complex etiopathology, which mostly remains elusive. Although research has claimed that oxidative stress (OS) is the most likely underlying mechanism of idiopathic male infertility, the specific treatment of OS-mediated male infertility requires further investigation. Coenzyme Q10 (CoQ10), a vitamin-like substance, has been found in measurable levels in human semen. It exhibits essential metabolic and antioxidant functions, as well as playing a vital role in mitochondrial bioenergetics. Thus, CoQ10 may be a key player in the maintenance of biological redox balance. CoQ10 concentrations in seminal plasma directly correlate with semen parameters, especially sperm count and sperm motility. Seminal CoQ10 concentrations have been shown to be altered in various male infertility states, such as varicocele, asthenozoospermia, and medical or surgical regimens used to treat male infertility. These observations imply that CoQ10 plays an important physiological role in the maintenance and amelioration of semen quality. The present article thereby aimed to review the possible mechanisms through which CoQ10 plays a role in the regulation of male reproductive function, and to concisely discuss its efficacy as an ameliorative agent in restoring semen parameters in male infertility, as well as its impact on OS markers, sperm DNA fragmentation, pregnancy, and assisted reproductive technology outcomes.

Impact of Coenzyme Q10 and Selenium on Seminal Fluid Parameters and Antioxidant Status in Men with Idiopathic Infertility

Oxidative stress (OS) is a key contributing factor in 30-80% of male infertility cases. To date, several antioxidant treatments have been put forth to manage OS-induced male infertility. This study intended to elucidate the impact of coenzyme Q10 (CoQ10) and selenium on seminal fluid parameters and antioxidant status in infertile men with idiopathic oligoasthenoteratospermia (OAT). In this prospective study, 70 patients with idiopathic OAT were randomly allocated to receive CoQ10 (200 mg/day) or selenium (200 μg/day) for 3 months. Semen quality parameters (following WHO guidelines, 5th edition), total antioxidant capacity (TAC), catalase (CAT), and superoxide dismutase (SOD) activities were compared before and after the treatment. The results of the study showed an increase in sperm concentration with CoQ10 treatment (p < 0.01) as well as increased progressive sperm motility (p < 0.01 and p < 0.05) and total sperm motility (p < 0.01 and p < 0.05) with CoQ10 and selenium treatment respectively. There was also a significant improvement in TAC (p < 0.01 and p < 0.05) and SOD (p < 0.01 and p < 0.05) following treatment with CoQ10 and selenium respectively while CAT improved only with CoQ10 therapy (p < 0.05). Sperm concentration, motility, and morphology also correlated significantly with TAC, SOD, and CAT (r = 0.37-0.76). In conclusion, treatment with CoQ10 (200 mg) or selenium (200 μg) could improve sperm concentration, motility, and antioxidant status in infertile men with idiopathic OAT with CoQ10 providing the higher improvement.

Simplified sperm testing devices: a possible tool to overcome lack of accessibility and inconsistency in male factor infertility diagnosis. An opportunity for low- and middle- income countries

Background

Manual semen assessment (MSA) is a key component in a male’s fertility assessment. Clinicians rely on it to make diagnostic and treatment decisions. When performed manually, this routine laboratory test is prone to variability due to human intervention which can lead to misdiagnosis and consequently over- or under- treatment. For standardisation, continuous training, quality control (QC) programs and pricy Computer-Assisted Sperm Analysis (CASA) systems have been proposed, yet, without resolving intra- and inter-laboratory variability. In response, promising simplified sperm testing devices, able to provide cost-effective point-of-care male infertility diagnosis are prospected as a plausible solution to resolve variability and increase access to sperm testing.

Materials and methods

A throughout literature research for semen testing, sperm analysis, smart-phone assisted semen analysis, ‘at-home’ semen testing, male infertility, infertility in developing countries, infertility in low- and middle-income countries (LMIC) and quantitative sperm analysis was performed. A total of 14 articles, specific to ‘at-home’ simplified sperm assessment, were included to treat the core subject.

Results

Continuous training and consistent QC, are sine qua none conditions to achieve accurate and comparable MSA. Compliance does not rule-out variability, nevertheless. Emerging simplified sperm assessment devices are an actual alternative to resolve the lack of standardisation and accessibility to sperm analysis. YO ® , SEEM ® , and ExSeed ® are commercially available, user-friendly smartphone-based devices which can accurately measure volume, sperm concentration (millions/ml) and total motile sperm count. More broadly, by cost-effectiveness, availability, accuracy and convenient application, these devices could effectively select patients for first-line artificial reproduction treatments such as intrauterine insemination.

Conclusions

Accuracy and cost-effectiveness make smart-phone based sperm testing devices a practical and realistic solution to overcome variability in MSA. Importantly, these tools represent an actual opportunity to standardise and improve male subfertility diagnosis and treatment, especially in LMIC. However, before clinical application is possible, guidelines, further testing with special attention on accuracy in washed sperm, availability, cost-benefit and reliability are required.

Functional and Taxonomic Dysbiosis of the Gut, Urine, and Semen Microbiomes in Male Infertility

BACKGROUND

Little is known about the role of the genitourinary and gastrointestinal microbiota in the pathogenesis of male infertility.

OBJECTIVE

To compare the taxonomic and functional profiles of the gut, semen, and urine microbiomes of infertile and fertile men.

DESIGN, SETTING, AND PARTICIPANTS

We prospectively enrolled 25 men with primary idiopathic infertility and 12 healthy men with proven paternity, and we collected rectal swabs, semen samples, midstream urine specimens, and experimental controls.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We performed comprehensive semen analysis, 16S rRNA sequencing for quantitative high-resolution taxonomy, and shotgun metagenomics with a median of 140 million reads per sample for functional metabolic pathway profiling.

RESULTS AND LIMITATIONS

We identified a diverse semen microbiome with modest similarity to the urinary microbiome. Infertile men harbored increased seminal α-diversity and distinct β-diversity, increased seminal Aerococcus, and decreased rectal Anaerococcus. Prevotella abundance was inversely associated with sperm concentration, and Pseudomonas was directly associated with total motile sperm count. Vasectomy appeared to alter the seminal microbiome, suggesting a testicular or epididymal contribution. Anaerobes were highly over-represented in the semen of infertile men with a varicocele, but oxidative stress and leukocytospermia were associated with only subtle differences. Metagenomics data identified significant alterations in the S-adenosyl-L-methionine cycle, which may play a multifaceted role in the pathogenesis of infertility via DNA methylation, oxidative stress, and/or polyamine synthesis.

CONCLUSIONS

This pilot study represents the first comprehensive investigation into the microbiome in male infertility. These findings provide the foundation for future investigations to explore causality and identify novel microbiome-based diagnostics and therapeutics for men with this complex and emotionally devastating disease.

PATIENT SUMMARY

We explored the resident populations of bacteria living in the gut, semen, and urine of infertile and fertile men. We found several important bacterial and metabolic pathway differences with the potential to aid in diagnosing and treating male infertility in the future.

Utility of Antioxidants in the Treatment of Male Infertility: Clinical Guidelines Based on a Systematic Review and Analysis of Evidence

It is widely accepted that oxidative stress plays an important role in the pathophysiology of male infertility and that antioxidants could have a significant role in the treatment of male infertility. The main objectives of this study are: 1) to systematically review the current evidence for the utility of antioxidants in the treatment of male infertility; and 2) propose evidence-based clinical guidelines for the use of antioxidants in the treatment of male infertility. A systematic review of the available clinical evidence was performed, with articles published on Scopus being manually screened. Data extracted included the type of antioxidant used, the clinical conditions under investigation, the evaluation of semen parameters and reproductive outcomes. The adherence to the Cambridge Quality Checklist, Cochrane Risk of Bias for randomized controlled trials (RCTs), CONSORT guidelines and JADAD score were analyzed for each included study. Further, we provided a Strength Weakness Opportunity Threat (SWOT) analysis to analyze the current and future value of antioxidants in male infertility. Of the 1,978 articles identified, 97 articles were included in the study. Of these, 52 (53.6%) were uncontrolled (open label), 12 (12.4%) unblinded RCTs, and 33 (34.0%) blinded RCTs, whereas 44 (45.4%) articles tested individual antioxidants, 31 (32.0%) a combination of several products in variable dosages, and 22 (22.6%) registered antioxidant products. Based on the published evidence, we 1) critically examined the necessity of additional double-blind, randomized, placebo-controlled trials, and 2) proposed updated evidence-based clinical guidelines for antioxidant therapy in male infertility. The current systematic review on antioxidants and male infertility clearly shows that antioxidant supplementation improves semen parameters. In addition, it provides the indications for antioxidant treatment in specific clinical conditions, including varicocele, unexplained and idiopathic male infertility, as well as in cases of altered semen quality.

Seminal oxidation-reduction potential as a possible indicator of impaired sperm parameters in Turkish population

Oxidative stress (OS) has been shown to have a key role in male infertility. Recently, a new measurement method has been developed to measure the overall oxidation-reduction potential (ORP) in a semen sample known as the MiOXSYS system. The aim of this study was to investigate the correlation of sperm parameters with oxidative stress levels determined by ORP and to evaluate whether the current limit is able to distinguish abnormal sperm parameters from normal ones in Turkish population. Semen samples of 121 patients who applied for infertility investigation were divided into two groups as (OS +; n:39) and (OS -; n:82). Semen parameters were compared between groups. Sperm concentration, total motility and progressive motility were found to be significantly lower in OS (+) patients compared to those OS (-), while immotile sperm count was significantly higher in OS (+) patients. Oxidative stress determined by MiOXSYS system was found to be related to reduced sperm parameters in Turkish population, which may be used as an indicator of poor sperm parameters and a support to routine semen analysis. In addition, recommended reference value was found to be reliable in distinguishing normal from impaired semen parameters.

Redox potential in human semen: Validation and qualification of the MiOXsys assay

Seminal oxidative stress (OS) is a major contributing factor to male infertility. Semen analysis cannot identify reactive oxygen species (ROS), which can be measured using a chemiluminescence assay. Measurement of redox potential provides a more comprehensive assessment of OS, although the test has yet to be fully validated. This study aimed to validate the MiOX^sys analyser for measuring static oxidation-reduction potential (sORP). Results demonstrated that duplicate measurements must be taken, sensors must be batch tested, and sockets should be regularly changed to avoid inconsistency in measurement. Measurement of sORP using MiOX^sys exhibited good reproducibility across different operators (p = 0.469), analysers (p = 0.963) and days (p = 0.942). It is not affected by mechanical agitation (p = 0.522) or snap freezing and thawing (p = 0.823). The stability of sORP over time requires further verification, particularly in samples with high initial sORP. Measurement is temperature sensitive between 2 and 37°C, significantly increasing with increasing temperature (p = 0.0004). MiOX^sys is a more stable assay for assessing OS than chemiluminescence methods and permits greater flexibility for sample handling. MiOX^sys could be implemented to complement semen analysis as part of routine diagnostic testing for male infertility and may be useful in identifying contributing factors to idiopathic infertility.

Recent advances and controversies in diagnosing and treating male infertility

Interest in male infertility has increased, as it plays an important role in up to 50% of couples struggling with infertility, which is an estimated 48.5 million couples globally. Despite recent advances, diagnosing and treating male infertility remain a significant clinical challenge owing to complex multifactorial pathways and the diversity of treatment options. This review will assess current controversial topics on male infertility such as the use of home-based semen testing, management of subclinical varicocele, and recent advances in the field of sperm proteomics.

Oxidative Stress in Reproduction: A Mitochondrial Perspective

Mitochondria are fundamental organelles in eukaryotic cells that provide ATP through oxidative phosphorylation. During this process, reactive oxygen species (ROS) are produced, and an imbalance in their concentrations can induce oxidative stress (OS), causing cellular damage. However, mitochondria and ROS play also an important role in cellular homeostasis through a variety of other signaling pathways not related to metabolic rates, highlighting the physiological relevance of mitochondria–ROS interactions. In reproduction, mitochondria follow a peculiar pattern of activation, especially in gametes, where they are relatively inactive during the initial phases of development, and become more active towards the final maturation stages. The reasons for the lower metabolic rates are attributed to the evolutionary advantage of keeping ROS levels low, thus avoiding cellular damage and apoptosis. In this review, we provide an overview on the interplay between mitochondrial metabolism and ROS during gametogenesis and embryogenesis, and how OS can influence these physiological processes. We also present the possible effects of assisted reproduction procedures on the levels of OS, and the latest techniques developed to select gametes and embryos based on their redox state. Finally, we evaluate the treatments developed to manage OS in assisted reproduction to improve the chances of pregnancy.

Relationship of Seminal Oxidation-Reduction Potential with Sperm DNA Integrity and pH in Idiopathic Infertile Patients

Seminal oxidative stress (OS) is one of the most promising factors to describe the causes of idiopathic male infertility. Redox balance is essential in several biological processes related to fertility, so alterations such as high reactive oxygen species (ROS) levels or low antioxidant agent levels can compromise it. MiOXSYS has been developed to evaluate the seminal static oxidation-reduction potential (sORP) and it has been proposed as an effective diagnostic biomarker. However, its relationship with parameters like sperm DNA fragmentation (SDF), chromatin compaction status or seminal pH requires further analysis, making it the object of this study. Semen and sORP analysis were performed for all samples. A terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL) and Comet assay were used to assess SDF and chromomycin a3 (CMA3) test to assess sperm chromatin compaction. Regarding sORP measures, it was found that alkaline pH has an effect on sample reproducibility. To our knowledge, this unexpected effect has not been previously described. A statistical analysis showed that sORP correlated negatively with CMA3 positive cells and sperm motility, but not with SDF. As redox dysregulation, which occurs mainly at the testicular and epididymal level, causes chromatin compaction problems and leaves DNA exposed to damage, an excess of ROS could be counterbalanced further by a seminal supply of antioxidant molecules, explaining the negative correlation with CMA3 positive cells but no correlation with SDF. Our results show that the study of idiopathic infertility would benefit from a combined approach comprising OS analysis, SDF and chromatin compaction analysis.

Multi-center evaluation of oxidation-reduction potential by the MiOXSYS in males with abnormal semen

According to the World Health Organization (WHO), oxidative stress (OS) is a significant contributor to male infertility. Seminal OS can be measured by a number of assays, all of which are either costly or time sensitive and/or require large semen volume and complex instrumentation. One less expensive alternative is to quantify the oxidation-reduction potential (ORP) with the MiOXSYS. In this international multi-center study, we assessed whether ORP levels measured by the MiOXSYS could distinguish semen samples that fall within the 2010 WHO normal reference values from those that do not. Semen samples were collected from 2092 patients in 9 countries; ORP was normalized to sperm concentration (mV/10⁶ sperm/ml). Only those samples with a concentration >1 × 10⁶ sperm ml^–1 were included. The results showed that 199 samples fell within the WHO normal reference range while the remaining 1893 samples did not meet one or more of the criteria. ORP was negatively correlated with all semen parameters (P < 0.01) except volume. The area under the curve for ORP was 0.765. The ORP cut-off value (1.34 mV/10⁶ sperm/ml) was able to differentiate specimens with abnormal semen parameters with 98.1% sensitivity, 40.6% specificity, 94.7% positive predictive value (PPV) and 66.6% negative predictive value (NPV). When used as an adjunct to traditional semen analysis, ORP levels may help identify altered functional status of spermatozoa caused by OS in cases of idiopathic male infertility and in male partners of couples suffering recurrent pregnancy loss, and thereby directing these men to relevant medical therapies and lifestyle modifications.

Sperm DNA Integrity and Male Fertility in Farm Animals: A Review

The accurate prediction of male fertility is of major economic importance in the animal breeding industry. However, the results of conventional semen analysis do not always correlate with field fertility outcomes. There is evidence to indicate that mammalian fertilization and subsequent embryo development depend, in part, on the inherent integrity of the sperm DNA. Understanding the complex packaging of mammalian sperm chromatin and assessment of DNA integrity could potentially provide a benchmark in clinical infertility. In the era of assisted reproduction, especially when in-vitro fertilization or gamete intrafallopian transfer or intracytoplasmic sperm injection is used, assessment of sperm DNA integrity is important because spermatozoa are not subjected to the selection process occurring naturally in the female reproductive tract. Although sperm DNA integrity testing measures a significant biological parameter, its precise role in the infertility evaluation in farm animals remains unclear. In this review, the earlier findings on sperm DNA integrity in relation to male fertility are compiled and analyzed. Furthermore, the causes and consequences of sperm DNA damage are described, together with a review of advances in methods for detection of sperm DNA damage, and the prognostic value of sperm DNA quality on male fertility.

Evaluation of seminal oxidation-reduction potential in male infertility

The role of oxidative stress in male infertility has been broadly recognised, and the search for a new marker to determine the redox environment in semen has gained considerable interest. Oxidation-reduction potential (ORP) or redox potential, is a measure of the electron transfer from antioxidants to oxidants and provides information on the redox balance. In this review, the benefits of ORP as a new oxidative stress marker, the protocol for its evaluation and the importance of its measurement in the context of male infertility are discussed. In association with the standard semen analysis, seminal ORP has been analysed to evaluate semen quality and male fertility status. However, further studies are required to establish its use in assisted reproductive techniques (ART) practice.

Are specialized sperm function tests clinically useful in planning assisted reproductive technology?

40-year-old male patient and 32-year-old female partner, with a history of primary infertility of two years duration. The workup revealed idiopathic mild oligoasthenotheratozoospermia, and no apparent female infertility factors. The couple has failed three intrauterine insemination (IUI) cycles, planning more IUI cycles but also considering in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI).

Seminal oxidation-reduction potential and sperm DNA fragmentation index increase among infertile men with varicocele

Varicocele is a common cause of male infertility. It is reported that low sperm concentration, motility and morphology are indicative of increased sperm DNA fragmentation index (DFI) in men with varicocele. Although research has been conducted into the relationship between varicocele and DFI, little is known about seminal oxidation-reduction potential (ORP) in varicocele patients. We assessed the relationship between varicocele with seminal ORP and sperm DFI in both fertile and infertile men. This prospective case-control study compared the findings from infertile men with varicocele to those of men with normal spermatogenesis without varicocele. Semen samples were collected and assessed using the WHO (2010) guidelines. ORP was measured (mV) and normalized to sperm concentration (mV/10⁶ sperm/mL). DFI was measured using the sperm chromatin structure assay (SCSA) method. For group comparisons, only samples with a concentration >1 × 10⁶ sperm/mL were included. Infertile men with varicocele had significantly lower mean sperm concentration, motility and total sperm count. Conversely, infertile men with varicocele had a significantly higher mean serum FSH level, and higher ORP and DFI values than fertile controls. ORP was higher in patients with varicocele and positively correlated with DFI (p < 0.01). ORP and DFI showed significant negative correlations with semen parameters (sperm concentration, motility and total sperm count) in infertile men with a varicocele.

Interventions to Prevent Sperm DNA Damage Effects on Reproduction

Excessive oxidation and antioxidant imbalance resulting from several conditions may cause sperm DNA damage, which, in turn, affect male fertility, both natural and assisted. Sperm DNA damage transferred to the embryo might also affect the health of offspring. Several conditions associated with excessive oxidative stress are modifiable by the use of specific treatments, lifestyle changes, and averting exposure to environmental/occupational toxicants. Here, we discuss the strategies to reduce sperm DNA damage with a focus on clinical and surgical interventions.

Rosiglitazone in the thawing medium improves mitochondrial function in stallion spermatozoa through regulating Akt phosphorylation and reduction of caspase 3

BACKGROUND

The population of stallion spermatozoa that survive thawing experience compromised mitochondrial functionality and accelerated senescence, among other changes. It is known that stallion spermatozoa show very active oxidative phosphorylation that may accelerate sperm senescence through increased production of reactive oxygen species. Rosiglitazone has been proven to enhance the glycolytic capability of stallion spermatozoa maintained at ambient temperature.

OBJECTIVES

Thus, we hypothesized that thawed sperm may also benefit from rosiglitazone supplementation.

MATERIALS AND METHODS

Thawed sperm were washed and resuspended in Tyrodes media, and the samples were divided and supplemented with 0 or 75 μM rosiglitazone. After one and two hours of incubation, mitochondrial functionality, Akt phosphorylation and caspase 3 activity were evaluated. Additional samples were incubated in the presence of an Akt1/2 inhibitor, compound C (an AMPK inhibitor) or GW9662 (an antagonist of the PPARγ receptor).

RESULTS

Rosiglitazone maintained Akt phosphorylation and reduced caspase 3 activation (p<0.01), both of which were prevented by incubation in the presence of the three inhibitors. Rosiglitazone also enhanced mitochondrial functionality (P<0.01).

CONCLUSION

We provide the first evidence that the functionality of frozen stallion spermatozoa can be potentially improved after thawing through the activation of pro survival pathways, providing new clues for improving current sperm biotechnology.

Oxidation reduction potential: a new biomarker of male infertility

Oxidative stress is considered a major etiology for male infertility, more specifically idiopathic infertility. The causes of seminal oxidative stress can be intrinsic, such as varicocele or due to the presence of active leukocytes and immature germ cells. Reported external causes are smoking, alcohol or exposure to environmental toxins. Traditional methods to determine the seminal oxidative stress do not evaluate this status directly, but rather measure its components or intermediate products indirectly, instead. The major disadvantages of the traditional methods are related with time and cost as these methods are extremely time consuming and require expensive equipment, consumables and highly skilled laboratory personnel. To overcome these drawbacks, the MiOXSYS® system, a method which directly measures the oxidation-reduction potential (ORP), was developed. The evaluation of the ORP using MiOXSYS® is cost-effective, easy and quick. However, this newly introduced method to evaluate the oxidative status of semen still requires validation in different andrology laboratory settings across the world.

Mercury at environmental relevant levels affects spermatozoa function and fertility capacity in bovine sperm

Over the last several years human sperm quality was found to be significantly reduced and the role environmental contaminants play in this phenomenon remain to be determined. Mercury (Hg) is one of the most widespread contaminants; however the correlation between metal exposure and adverse consequences on human and animals fertility are not completely established. The aim of this study was to determine the effects of direct exposure to inorganic Hg on male gametes using spermatozoa (bovine sperm) which characteristically resemble human sperm. Sperm were divided and incubated for 0.5, 1 or 2 h at low levels of Hg: i) Control: without exposure; ii) Hg8 nM: mercury chloride (HgCl₂) at 8 nM and iii) Hg8 μM: HgCl₂ at 8 μM. Sperm kinetics, morphology, sperm membrane integrity, and in vitro fertilization were assessed. In addition the levels of reactive oxygen species (ROS), lipid peroxidation and total antioxidant capacity were measured. Hg exposure for 2 h impaired sperm morphology and membrane integrity as well as kinetic parameters including curvilinear velocity and straight-line velocity, which are needed for fertilization as evidenced by the reduced fertilization rate in 8 μM Hg-treated gametes. Hg enhanced oxidative stress in male sperm as reflected by elevated levels of ROS and lipid peroxidation and decreased antioxidant capacity. Data demonstrated that low levels of Hg when incubated with spermatozoa are sufficient to increase oxidative stress, adversely affect sperm quality parameters, subsequently impairing sperm fertility capacity.

Laboratory assessment of oxidative stress in semen

Objectives

To evaluate different laboratory assessments of oxidative stress (OS) in semen and identify a cost-efficient and highly sensitive instrument capable of providing a comprehensive measure of OS in a clinical setting, as early intervention and an accurate diagnostic test are important because they help maintain a balance of free radicals and antioxidants; otherwise, excessive OS could lead to sperm damage and result in male infertility.

Materials and methods

A systematic literature search was performed through a MedLine database search using the keywords ‘semen’ AND ‘oxygen reduction potential’. We also reviewed the references of retrieved articles to search for other potentially relevant research articles and additional book chapters discussing laboratory assessments for OS, ranging from 1994 to 2017. A total of 29 articles and book chapters involving OS-related laboratory assays were included. We excluded animal studies and articles written in languages other than English.

Results

Direct laboratory techniques include: chemiluminescence, nitro blue tetrazolium, cytochrome C reduction test, fluorescein probe, electron spin resonance and oxidation–reduction potential (ORP). Indirect laboratory techniques include: measurement of Endtz test, lipid peroxidation, chemokines, antioxidants/micronutrients/vitamins, ascorbate, total antioxidant capacity, or DNA damage. Each of these laboratory techniques has its advantages and disadvantages.

Conclusion

Traditional OS laboratory assessments have their limitations. Amongst the prevalent laboratory techniques, ORP is novel and better option as it can be easily used in a clinical setting to provide a comprehensive review of OS. However, more studies are needed to evaluate its reproducibility across various laboratory centres.

Oxidation-reduction potential as a new marker for oxidative stress: Correlation to male infertility

Male infertility affects men worldwide. Oxidative stress (OS), characterized by an overabundance of reactive oxygen species (ROS) or a deficiency of antioxidants, is one of the major causes of male infertility. OS causes damage at the molecular level, which impairs lipids, proteins, and DNA. The cyclic cascade of redox reactions weakens sperm function which leads to poor semen parameters and eventual sterility. There is a need for advanced diagnostic tests that can quickly and accurately detect OS. Most commonly used assays can only measure single constituents of OS. However, the MiOXSYS System introduces a new strategy to detect OS by measuring the oxidation-reduction potential (ORP)--a direct evaluation of the redox balance between ROS and antioxidants. The MiOXSYS System has shown promise as a diagnostic tool in the evaluation of male infertility. This review explores the concept of ORP, details the principle of the MiOXSYS System, and summarizes the findings in clinical studies that support ORP measurement in semen.