Association of urinary metal element with semen quality: a cross-sectional study from Eastern China.

The effect of metallic elements on semen quality remains controversial, with limited evidence on the effects of metal mixtures. We conducted a study involving 338 participants from multiple centers in Eastern China, measuring 17 urinary metals and semen quality parameters. Our analysis used various statistical models, including multivariate logistic and linear regression, Bayesian Kernel Machine Regression, and weighted quantile sum models, to examine the associations between metal levels and semen quality. Logistic regression showed that higher urinary lead was associated with increased risk of abnormal sperm concentration (OR = 1.86, p = 0.021), arsenic to higher abnormal progressive motility risk (OR = 1.49, p = 0.027), and antimony to greater abnormal total motility risk (OR = 1.37, p = 0.018). Conversely, tin was negatively correlated with the risk of abnormal progressive motility (OR = 0.76, p = 0.012) and total motility (OR = 0.74, p = 0.003), respectively. Moreover, the linear models showed an inverse association between barium and sperm count, even after adjusting for other metals (ß = - 0.32, p < 0.001). Additionally, the WQS models showed that the metal mixture may increase the risk of abnormal total motility (ßWQS = 0.55, p = 0.046). In conclusion, semen quality may be adversely affected by exposure to metals such as arsenic, barium, lead, and antimony. The combined effect of the metal mixture appears to be particularly impaired total motility.

The short-term effect of COVID-19 infection history on semen parameters in men referred to infertility centres.

Context In recent years, the COVID-19 pandemic became a threat to human health and induced global concern. The SARS-CoV-2 virus causes various disorders in the body's systems, and the reproductive system is no exception. Further, the rate of infertile couples is increasing and part of this is related to male infertility. Aims The aim of the present study was to investigate the impacts of COVID-19 infection history on semen quality in men referred to public and private infertility centres. Methods In this research, patients were divided into two groups: 88 men with a history of COVID-19 (Covid+) and 51 men without (Covid-). After semen collection, sperm parameters, fertilisation rate and oxidative stress were investigated. Key results Sperms with normal morphology and mature chromatin in patients with COVID-19 infection history decreased, and seminal oxidative stress and sperm DNA fragmentation were increased; moreover, the fertilisation rate in the Covid+ group decreased in compare to the Covid- group. Conclusion COVID-19 infection increases oxidative stress in the semen, so has a negative effect on some sperm parameters and fertilisation rate. Implications COVID-19 infection impairs semen quality by increasing in oxidative stress, thus reducing the fertility potential.

Evaluation of the effectiveness of the use of exosomes in the regulation of the mitochondrial membrane potential of frozen/thawed spermatozoa.

Numerous studies confirm the involvement of extracellular vesicles (EVs) in the regulation of physiological processes of mammalian sperm cells. It has been proven that they take part in the processes of capacitation, acrosonmal reaction, and anti-oxidation. Despite growing interest in the biomedical potential (including the search for new reproductive biomarkers) of EVs, the role of extracellular seminal vesicles in maintaining semen quality during cryopreservation has not yet been established. Therefore, the objective of this experiment was to evaluate the effectiveness of the use in the regulation of the mitochondrial membrane potential of bovine sperm and to explain the mechanisms of EV action during cell cryopreservation. Exosomes were isolated from bull semen plasma, measured, and used for extender supplementation. Semen samples were collected from Simmental bulls, diluted, and pre-evaluated. Then they were divided into equal fractions that did not contain EVs or were supplemented with 0.75; 1.5 and 2.25 mg/ml of EVs. The test samples were frozen/thawed and the mitochondrial membrane potential, DNA integrity, and viability were evaluated. EVs have been established to have a positive effect on cryopreserved sperm structures. The most favourable level of EVs was 1.5 mg / ml, which can be successfully to improve cell cryostability during freezing/thawing. In this study, exosomes isolated from the sperm plasma and supplemented with a concentrated dose in the extender for sperm freezing were shown to significantly improve cryostability of cells by supporting the potentials of the mitochondrial membrane and protecting the cytoplasmic membrane of spermatozoa.

Outcomes of dietary alpha-lipoic acid on testicular vascularization, steroid hormones, and seminal quality in aged Baladi bucks.

BACKGROUND: Senescence is accompanied by a progressive decrease in male reproductive performance, mainly due to oxidative stress and endothelial dysfunction. Alpha lipoic acid (ALA) is a potent antioxidant, that diffuses freely in aqueous and lipid phases, possessing anti-inflammatory and anti-apoptotic properties. This study aimed to examine the effects of supplemental dietary ALA on testicular hemodynamics (TH), circulating hormones, and semen quality in aged goats. Twelve Baladi bucks were divided into two groups (n = 6 each); the first fed a basic ration and served as a control group (CON), while the second received the basic ration supplemented with 600 mg ALA/ kg daily for consecutive eight weeks (ALA). RESULTS: There were improvements in testicular blood flow in the ALA group evidenced by a lower resistance index (RI) and pulsatility index (PI) concurrent with higher pampiniform-colored areas/pixel (W3-W6). There were increases in testicular volume and decreases in echogenicity (W3-W5; ALA vs. CON). Compared to the CON, ALA-bucks had higher serum concentrations of testosterone, estradiol, and nitric oxide (W3-W5). There were enhancements in semen traits (progressive motility, viability, morphology, and concentration, alanine aminotransferase enzyme) and oxidative biomarkers (catalase, total antioxidant capacity, and malondialdehyde). CONCLUSIONS: ALA dietary supplementation (600 mg/kg diet) improved aged bucks' reproductive performance by enhancing the testicular volume, testicular hemodynamics, sex steroids, and semen quality.

Lead and calcium crosstalk tempted acrosome damage and hyperpolarization of spermatozoa: signaling and ultra-structural evidences.

BACKGROUND: Exposure of humans and animals to heavy metals is increasing day-by-day; thus, lead even today remains of significant public health concern. According to CDC, blood lead reference value (BLRV) ranges from 3.5 µg/dl to 5 µg/dl in adults. Recently, almost 2.6% decline in male fertility per year has been reported but the cause is not well established. Lead (Pb2+) affects the size of testis, semen quality, and secretory functions of prostate. But the molecular mechanism(s) of lead toxicity in sperm cells is not clear. Thus, present study was undertaken to evaluate the adverse effects of lead acetate at environmentally relevant exposure levels (0.5, 5, 10 and 20 ppm) on functional and molecular dynamics of spermatozoa of bucks following in vitro exposure for 15 min and 3 h. RESULTS: Lead significantly decreased motility, viable count, and motion kinematic patterns of spermatozoa like curvilinear velocity, straight-line velocity, average path velocity, beat cross frequency and maximum amplitude of head lateral displacement even at 5 ppm concentration. Pb2+ modulated intracellular cAMP and Ca2+ levels in sperm cells through L-type calcium channels and induced spontaneous or premature acrosome reaction (AR) by increasing tyrosine phosphorylation of sperm proteins and downregulated mitochondrial transmembrane potential. Lead significantly increased DNA damage and apoptosis as well. Electron microscopy studies revealed Pb2+ -induced deleterious effects on plasma membrane of head and acrosome including collapsed cristae in mitochondria. CONCLUSIONS: Pb2+ not only mimics Ca2+ but also affects cellular targets involved in generation of cAMP, mitochondrial transmembrane potential, and ionic exchange. Lead seems to interact with Ca2+ channels because of charge similarity and probably enters the sperm cell through these channels and results in hyperpolarization. Our findings also indicate lead-induced TP and intracellular Ca2+ release in spermatozoa which in turn may be responsible for premature acrosome exocytosis which is essential feature of capacitation for fertilization. Thus, lead seems to reduce the fertilizing capacity of spermatozoa even at 0.5 ppm concentrations.

Detection of AZF microdeletions and analysis of reproductive hormonal profiles in Hainan men undergoing assisted reproductive technology.

BACKGROUND: Male infertility has become a global health problem, and genetic factors are one of the essential causes. Y chromosome microdeletion is the leading genetic factor cause of male infertility. The objective of this study is to investigate the correlation between male infertility and Y chromosome microdeletions in Hainan, the sole tropical island province of China. METHODS: We analyzed the semen of 897 infertile men from Hainan in this study. Semen analysis was measured according to WHO criteria by professionals at the Department of Reproductive Medicine, the First Affiliated Hospital of Hainan Medical University, where samples were collected. Y chromosome AZF microdeletions were confirmed by detecting six STS markers using multiple polymerase chain reactions on peripheral blood DNA. The levels of reproductive hormones, including FSH, LH, PRL, T, and E2, were quantified using the enzyme-linked immunosorbent assay (ELISA). RESULTS: The incidence of Y chromosome microdeletion in Hainan infertile men was 7.13%. The occurrence rate of Y chromosome microdeletion was 6.69% (34/508) in the oligozoospermia group and 7.71% (30/389) in the azoospermia group. The deletion of various types in the AZF subregion was observed in the group with azoospermia, whereas no AZFb deletion was detected in the oligozoospermia group. Among all patients with microdeletions, the deletion rate of the AZFc region was the higher at 68.75% (44 out of 64), followed by a deletion rate of 6.25% (4 out of 64) for the AZFa region and a deletion rate of 4.69% (3 out of 64) for the AZFb region. The deletion rate of the AZFa region was significantly higher in patients with azoospermia than in patients with oligozoospermia (0.51% vs. 0.39%, p < 0.001). In comparison, the deletion rate of the AZFc region was significantly higher in patients with oligozoospermia (3.08% vs. 6.30%, p < 0.001). Additionally, the AZFb + c subregion association deletion was observed in the highest proportion among all patients (0.89%, 8/897), followed by AZFa + b + c deletion (0.56%, 5/897), and exclusively occurred in patients with azoospermia. Hormone analysis revealed FSH (21.63 ± 2.01 U/L vs. 10.15 ± 0.96 U/L, p = 0.001), LH (8.96 ± 0.90 U/L vs. 4.58 ± 0.42 U/L, p < 0.001) and PRL (263.45 ± 21.84 mIU/L vs. 170.76 ± 17.10 mIU/L, p = 0.002) were significantly increased in azoospermia patients with microdeletions. Still, P and E2 levels were not significantly different between the two groups. CONCLUSIONS: The incidence of AZF microdeletion can reach 7.13% in infertile men in Hainan province, and the deletion of the AZFc subregion is the highest. Although the Y chromosome microdeletion rate is distinct in different regions or populations, the regions mentioned above of the Y chromosome may serve an indispensable role in regulating spermatogenesis. The analysis of Y chromosome microdeletion plays a crucial role in the clinical assessment and diagnosis of male infertility.

Correlation between sperm DNA fragmentation and methylation in male partners of couples with idiopathic recurrent pregnancy loss.

With ∼50% recurrent pregnancy loss cases being termed idiopathic (iRPL), understanding of contribution of male factors to iRPL is still lacking. Higher prevalence of sperm DNA fragmentation index (DFI) and lower sperm 5-methylcytosine (5-mC) levels have been previously reported in male partners of iRPL couples and shed light on importance of the male gamete in maintenance of a successful pregnancy. The present study aimed to determine the serum sex steroid hormone levels, sperm DFI and 5-mC and correlation between them in male partners of fertile and iRPL couples. Further, correlation between sperm DFI and 5-mC with semen parameters and paternal age in both groups were determined. 36 male partners of fertile couples and 45 male partners of women experiencing iRPL were enrolled for this study and semen and blood samples were collected. Serum testosterone and estradiol levels were measured by ELISA; sperm DFI and global 5-mC were determined by TUNEL assay and ELISA respectively. Significantly higher serum testosterone levels were noted in the iRPL group (p = 0.028). Incidence of sperm DNA fragmentation was found to be higher in the iRPL study group but with no significance difference. No significant differences in sperm 5-mC values were noted. Upon correlation analysis within both groups, strong significant negative correlation of sperm DFI % and 5-mC % was observed in the control group (p < 0.001) but not the iRPL group (p = 0.249). Hence, we infer that with lower 5-mC levels in sperm genome, there is a higher incidence of sperm DFI in fertile men. However, this trend is not noted in men of iRPL group which could possibly be due to other underlying epigenetic alterations in genomic regions probably unsusceptible to fragmentation. On the other hand, no significant correlations of semen parameters, testosterone, estradiol and paternal age with sperm DFI and 5-mC were noted in both groups.

Enhancing cryopreserved ram sperm quality at -80 °C with Spirulina platensis and Salvia verbenaca extracts.

This study was conducted in two steps to evaluate the influence of freezing methods and natural extracts on cryopreserved ram sperm quality. Initially, the research compared the effects of two freezing methods: liquid nitrogen (LN2) versus -80 °C, on post-thawed ram semen on total and progressive motilities and velocity parameters. Experiment I revealed no significant differences (P > 0.05) between the LN2 and -80 °C freezing methods, indicating similar effects on the analyzed parameters. Experiment II aimed to examine the influence of Spirulina platensis (SP) and Salvia verbenaca (SV) extracts added to egg yolk extender on cryopreserved sperm quality, utilizing the -80 °C freezing method. Various concentrations (1.25, 3.75, 6.25 and 8.75 µg*mL-1) of acetone (Ac-SP and Ac-SV) and hexanoic (Hex-SP), as well as methanolic (MeOH-SV) extracts, were added into the extender. A thorough assessment of post-thawed sperm quality parameters, encompassing motility, velocity parameters, viability, membrane integrity, abnormality and lipid peroxidation was conducted. The outcomes demonstrated that 1.25 and 3.75 g*mL-1 of Ac-SP and Hex-SP and 1.25 µg*mL-1 of AC-SV and MeOH-SV increased the post-thawed ram sperm quality. In conclusion, this study emphasizes the antioxidant properties of SP and SV extracts, highlighting their potential to protect cryopreserved sperm cells from oxidative stress at -80 °C.

Interplay between male gonadal function and overall male health.

The process-of-male reproduction is intricate, and various medical conditions-have the potential to disrupt spermatogenesis. Moreover, infertility in males can serve as an indicator of-potential future health issue. Numerous conditions with systemic implications have been identified, encompassing genetic factors (such as Klinefelter Syndrome), obesity, psychological stress, environmental factors, and others. Consequently, infertility assessment-presents an opportunity for comprehensive health counseling, extending-beyond discussions about reproductive goals. Furthermore, male infertility has been suggested as a harbinger of future health problems, as poor semen quality and a diagnosis of-male infertility are associated with an increased risk of hypogonadism, cardiometabolic disorders, cancer, and even mortality. This review explores the existing-literature on the relationship between systemic illnesses and male fertility, impacting both clinical-outcomes and semen parameters. The majority of the literature analyzed, which compared gonadal function with genetic, chronic, infectious or tumoral diseases, confirm the association between overall male health and infertility.

Proteomic Analysis of Differences in the Freezability of Porcine Sperm Identifies α-Amylase As a Key Protein.

To investigate the mechanisms underlying the differences in the freezability of boar semen, Yorkshire boars with freezing-tolerant semen (YT, n = 3), Yorkshire boars with freezing-sensitive semen (YS, n = 3), Landrace boars with freezing-tolerant semen (LT, n = 3), and Landrace boars with freezing-sensitive semen (LS, n = 3) were selected for this study. Their sperm was subjected to protein extraction, followed by data-independent acquisition proteomics and functional bioinformatics analysis. A total of 3042 proteins were identified, of which 2810 were quantified. Some key KEGG pathways were enriched, such as starch and sucrose metabolism, carbohydrate digestion and absorption, mineral absorption, the HIF-1 signaling pathway, and the necroptosis pathways. Through PRM verification, we found that several proteins, such as α-amylase and epididymal sperm-binding protein 1, can be used as molecular markers of the freezing resistance of boar semen. Furthermore, we found that the addition of α-amylase to cryoprotective extender could significantly improve the post-thaw motility and quality of boar semen. In summary, this study revealed some molecular markers and potential molecular pathways contributing to the high or low freezability of boar sperm, identifying α-amylase as a key protein. This study is valuable for optimizing boar semen cryopreservation technology.

Evaluation of predictive ability of linear type gonadal traits on reproductive capacity of breeding dairy bulls.

Dimensions of linear type traits facilitate selection of livestock for breeding and rearing. To date, use of linear type traits for selection of breeding bulls is highly concentric to scrotal circumference (SC), with probable overlook to other important traits. Present study reported the importance of various gonadal linear type traits on spermatozoa production, age-related changes in gonadal linear type traits of bulls and predictive ability of these traits on bulls' reproductive potentials. Among all gonadal traits, testicular density (TD), scrotal volume (SV), paired testicular weight (PWT) and SC were found most important predictor variables in order, which can discriminate between good/poor breeding bulls, that is, produced frozen semen doses (FSD) or not. Dimensions of gonadal traits increased significantly up to 36 months age and thereafter, development became slow and negligible. In contrast, TD decreased by 30%, 51%, 64%, 68% and 71% at 12, 24, 36, 48 and >49 months age, respectively, from its base value at 6 months. Bulls of lower TD (≤0.88 g/cm3) had significantly higher ejaculate volume (+9%), sperm motility, sperm concentration (+100 million/mL) and sperm output (+26%)/ejaculate as compared to bulls of higher TD (>0.88 g/cm3). Discriminant function was developed using TD, SV, PWT and SC to identify bulls of superior reproductive potentials. It was concluded that among the investigated traits, TD was the strongest to discriminate between FSD and Non-FSD bulls. Therefore, our findings suggested that TD could be more potential trait than SC for dairy bulls' breeding soundness evaluation and assessment of reproductive ability.

Dietary composition influences sperm quality and testis damage via endoplasmic reticulum stress in lambs.

BACKGROUND: The metabolic impacts of including soya meal, wheat gluten and corn gluten in the diet of male lambs could influence their reproductive performance. OBJECTIVES: An experiment was carried out to assess the effects of corn gluten, wheat gluten and soya meal on the reproductive system of male lambs. METHODS: Twenty-four male Morkaraman lambs, aged 9 months, were utilized in this study and were fed experimental diets for 56 days. The lambs were divided into a control group (soybean meal + safflower meal), a corn group (corn gluten) and a wheat group (wheat gluten). RESULTS: The serum follicle-stimulating hormone level of the control group was significantly higher and tumour necrosis factor-alpha (TNF-α) level was lower than the wheat and corn gluten groups (p < 0.05). The lowest malondialdehyde level in testicular tissue was observed in the control group, whereas the highest was in the wheat gluten group (p < 0.05). The glutathione level in the control group was significantly higher than in the other groups (p < 0.05). The corn gluten group showed the highest CHOP and IRE1 levels; the lowest Bcl-2 levels and the highest IL-1B and P2 × 7R levels were found in the wheat group; and the lowest TNF-α levels were in the control group (p < 0.05). Additionally, the study revealed that diet had a significant impact on spermatological parameters of the testis such as diameter, volume and weight (p < 0.05). CONCLUSIONS: These results concluded that the inclusion of different protein sources in the diet of reproductive male lambs affects the metabolism of testicular tissue.

Effect of Postbiotics Derived from Lactobacillus rhamnosus PB01 (DSM 14870) on Sperm Quality: A Prospective In Vitro Study.

Vaginally administered postbiotics derived from Lactobacillus were recently demonstrated to be effective in alleviating bacterial vaginosis and increasing pregnancy rates. However, their potential effect on sperm quality has not been well investigated. This controlled in vitro study aimed to assess the dose- and time-dependent effects of postbiotics derived from Lactobacillus rhamnosus PB01 (DSM 14870) on sperm quality parameters. The experiment was conducted in vitro to eliminate potential confounding factors from the female reproductive tract and vaginal microbiota. Sperm samples from 18 healthy donors were subjected to analysis using Computer-Aided Sperm Analysis (CASA) in various concentrations of postbiotics and control mediums at baseline, 60 min, and 90 min of incubation. Results indicated that lower postbiotic concentration (PB5) did not adversely affect sperm motility, kinematic parameters, sperm DNA fragmentation, and normal morphology at any time. However, concentrations exceeding 15% demonstrated a reduction in progressively motile sperm and a negative correlation with non-progressively motile sperm at all time points. These findings underscore the importance of balancing postbiotic dosage to preserve sperm motility while realizing the postbiotics' vaginal health benefits. Further research is warranted to understand the underlying mechanisms and refine practical applications in reproductive health.

Sperm YOLOv8E-TrackEVD: A Novel Approach for Sperm Detection and Tracking.

Male infertility is a global health issue, with 40-50% attributed to sperm abnormalities. The subjectivity and irreproducibility of existing detection methods pose challenges to sperm assessment, making the design of automated semen analysis algorithms crucial for enhancing the reliability of sperm evaluations. This paper proposes a comprehensive sperm tracking algorithm (Sperm YOLOv8E-TrackEVD) that combines an enhanced YOLOv8 small object detection algorithm (SpermYOLOv8-E) with an improved DeepOCSORT tracking algorithm (SpermTrack-EVD) to detect human sperm in a microscopic field of view and track healthy sperm in a sample in a short period effectively. Firstly, we trained the improved YOLOv8 model on the VISEM-Tracking dataset for accurate sperm detection. To enhance the detection of small sperm objects, we introduced an attention mechanism, added a small object detection layer, and integrated the SPDConv and Detect_DyHead modules. Furthermore, we used a new distance metric method and chose IoU loss calculation. Ultimately, we achieved a 1.3% increase in precision, a 1.4% increase in recall rate, and a 2.0% improvement in mAP@0.5:0.95. We applied SpermYOLOv8-E combined with SpermTrack-EVD for sperm tracking. On the VISEM-Tracking dataset, we achieved 74.303% HOTA and 71.167% MOTA. These results show the effectiveness of the designed Sperm YOLOv8E-TrackEVD approach in sperm tracking scenarios.

Association of lifestyle and occupational exposure factors with human semen quality: a cross-sectional study of 1060 participants.

The incidence of male infertility (MI) is rising annually. However, the lifestyle and occupational exposure factors contributing to MI remain incompletely understood. This study explored the effects of self-reported lifestyle and occupational exposure factors on semen quality. Among 1060 subjects invited to participate, 826 were eligible. The participants' general characteristics, lifestyle, and occupational exposure factors were collected immediately before or after semen evaluation through an online questionnaire. Initially, univariate analysis was used to investigate the relationship between the abovementioned factors and semen quality. The results indicated significant associations between low semen quality and various factors, including age, BMI, infertility type and duration, abstinence time, semen and sperm parameters, smoking, alcohol consumption, irregular sleep habits, and frequent exposure to high temperatures and chemicals at work (p < 0.05). Then, multivariate analysis was conducted to identify factors independently associated with low semen quality. Adjustment for relevant confounders was achieved by including factors with a p-value < 0.25 from univariate analyses as covariates in the binomial and ordered logistic regression models. The results suggested that alcohol consumption was a positive factor for sperm concentration (odds ratio [OR] = 0.60; 95% confidence interval [CI] = 0.36-0.99; p = 0.045). The groups with a BMI ≥ 24 and <28 kg/m2 showed a significant decrease in sperm progressive motility when compared to the reference group (BMI < 24 kg/m2) (OR = 0.63; 95% CI = 0.46-0.87, p = 0.005). In addition, the groups that drank green tea <1 time/week (OR = 1.52, 95% CI = 1.05-2.2) and 1-4 times/week (OR = 1.61, 95% CI = 1.02-2.54) exhibited significantly increased sperm DFI values compared with the group that drank green tea 5-7 times/week. In conclusion, these findings underscore the importance of maintaining a normal weight and regularly consuming green tea for men.

Impact of papain on the treatment of raw diluted dromedary semen.

A variety of parameters, including liquefaction and semen viscosity, affect the sperm's ability to travel and reach the egg for fertilization and conception. Given that the details behind the viscosity of the semen in male camels have not yet been fully clarified, the purpose of this study was to ascertain how the addition of papain affected the viscosity of fresh diluted camel semen. The study examined semen samples derived from camels that had distinct viscosities. Sperm motility, viability, abnormal sperm percentage, concentration, viscosity, morphometry, acrosome integrity and liquefaction were among the evaluations following 0, 5, 10, 20 or 30 min of incubation at 37°C with papain (0.004 mg/mL, 0.04 mg/mL or 0.4 mg/mL; a semen sample without papain was used as a control). A statistically significant interaction between the effects of papain concentrations and incubation time was found (F = 41.68, p = .0001). Papain concentrations (p = .0001) and incubation times (p = .0001) both had a statistically significant impact on viscosity, according to a simple main effects analysis. A lower viscosity was found (p < .05) at 0.04 mg/mL (0.1 ± 0.0) after 10 min of incubation. A simple main effects analysis showed that papain concentrations and incubation time have a statistically significant effect on sperm motility (p = .0001). At 0.04 mg/mL papain, the sperm motility % was higher (p < .05) after 10 min (64.4 ± 4.8), 20 min (68.4 ± 6.2), and 30 min incubation (72.2 ± 6.6) compared to 0, 5 min (38.3 ± 4.1 and 51.6 ± 5.0, respectively). In conclusion, the fresh diluted camel semen had the lowest viscosity properties after 10 min of incubation with 0.04 mg/mL papain, without compromising sperm motility, viability, acrosome integrity and sperm morphology.

Effects of long and short ejaculatory abstinence on sperm parameters: a meta-analysis of randomized-controlled trials.

Purpose: This study aimed to investigate the effects of ejaculatory abstinence on sperm parameters. Methods: This analysis was registered in PROSPERO (CRD42023472124). We performed a search on PubMed using the following text terms: (("sperm parameters" OR "sperm analysis" [Mesh]) AND ("sperm DNA fragmentation" OR "DNA fragmentation" [Mesh]) AND ("sexual abstinence" [Mesh] OR "abstinence")) and an advanced search in Scopus using the terms ("sperm parameters" OR "sperm parameters" OR "DNA fragmentation") AND ("abstinence"). The sperm parameters that were investigated were sperm volume, total sperm motility, progressive sperm motility, sperm concentration, sperm morphology, and sperm DNA fragmentation (SDF). A two-day cut-off as a "short" or "long" abstinence period has been defined. Results: Thirteen studies published between 2013 and 2022 were included in this meta-analysis. A total of 2,315 patients, ranging from 6 to 836 from each cohort, were enrolled in the study. We showed that longer abstinence time was associated with greater sperm concentration (mean difference [MD]: 8.19; p <0.01), sperm volume (MD: 0.96; p <0.01), and higher SDF (MD: 3.46; p <0.01), but lower progressive sperm motility (MD: -1.83; p <0.01). Otherwise, no statistically significant difference was observed in patients with longer vs. shorter abstinence times regarding total sperm motility (MD: -1.83; p = 0.06). Meta-regression analysis showed that days of abstinence were positively and linearly related to sperm concentration (slope: 3.74; p <0.01) and SDF (slope: 0.65; p = 0.044). Conclusions: According to our data, short ejaculatory abstinence is associated with better sperm quality. Indeed, a higher percentage of progressive sperm motility and lower levels of SDF have been reported in a short abstinence cohort. In contrast, the long abstinence group reported a higher sperm concentration. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023472124.

Effect of autologous platelet-rich plasma on the fertility and quality of cryopreserved buffalo bull semen: a comparative study using OptiXcell® and tris egg yolk extenders.

BACKGROUND: Buffalo spermatozoa have a distinct membrane structure that makes them more vulnerable to cryopreservation, resulting in lower-quality post-thawed sperm. This decreases the success rate of artificial insemination in buffaloes. Understanding and addressing these specific vulnerabilities are essential for improving reproductive techniques in buffalo populations. The properties of cryopreserved buffalo bull semen were examined in this study regarding the impact of adding autologous platelet-rich plasma (PRP) to OptiXcell® or Tris egg yolk-based extenders. Ten buffalo bulls were used to collect semen. Each bull's ejaculate was separated into two main equal amounts, each of which was then diluted with either OptiXcell® or Tris egg yolk-based extender, supplemented with various PRP concentrations (5%, 10%, and 15%), and the control (0%), before being cryopreserved according to established protocols. Following equilibration and thawing, the quality and functionality of the sperm were evaluated, along with the antioxidant enzyme activities (GSH and TAC), malondialdehyde (MDA) content, and in vivo fertilization rate of the thawed semen. RESULTS: All PRP concentrations in both extenders, particularly 10% PRP, improved the quality and functionality of the sperm in both equilibrated and frozen-thawed semen. Additionally, the antioxidant enzyme activities in both extenders were higher in the PRP-supplemented groups compared to the control group in thawed semen (P < 0.05). All post-thaw sperm quality, antioxidant enzyme activities, and functionality aside from DNA integrity were higher (P < 0.05) in the PRP-supplemented OptiXcell® than in the PRP-supplemented Tris egg yolk-based extender. The fertility of cryopreserved semen in the extenders supplemented with 10% and 15% PRP increased (P < 0.05) significantly more than that of the control extenders, with 10% PRP being the optimum concentration in OptiXcell® (80%) compared to that of Tris egg yolk-based extender (66.67%) and control of two extenders (53.33% and 46.67%, respectively). CONCLUSIONS: Even though autologous PRP-supplemented extenders have a protective impact on equilibrated and cryopreserved semen, 10% PRP-supplemented OptiXcell® extenders are more effective at preserving post-thaw semen quality, functionality, and antioxidant capacity, which increases the in vivo fertility of buffalo bulls.

Heat shock protein 70 kDa (HSP70) is involved in the maintenance of pig sperm function throughout liquid storage at 17 °C.

At present, liquid storage is the most efficient method for pig semen preservation. This approach relies upon reducing sperm metabolism, allowing for the maintenance of cell lifespan. In this context, the study of proteins that could protect sperm during liquid storage is of high relevance. The 70 kDa Heat Shock Protein (HSP70) is an anti-apoptotic protein that has been reported to be relevant to sperm survival. Thus, we explored the role of HSP70 during prolonged storage of pig semen at 17 °C. Six semen pools were incubated with YM-1 (0, 0.05, 0.1 and 0.2 µM), an HSP70 inhibitor, and stored at 17 °C for 21 days. On days 0, 4, 10, 14 and 21, sperm quality and function were evaluated through flow cytometry and Computer-Assisted Sperm Analysis (CASA), and HSP70 activity and chromatin condensation were also determined. While inhibition of HSP70 increased progressive motility, Ca2+ and Reactive Oxygen Species (ROS) levels, and mitochondrial activity during the first 10 days of storage, it had a detrimental effect on sperm motility after 14 and 21 days. In spite of this, sperm viability was not altered. We can conclude that HSP70 contributes to the liquid storage of pig semen because it keeps mitochondrial activity low, which is needed for the maintenance of sperm function.

Update of the cooling protocol for antibiotic-free storage of boar semen at 5°C improves sperm quality and maintains low bacterial counts.

Preserving boar semen at 5°C instead of the conventional storage temperature of 17°C would enable a reduction of antibiotic use in pig insemination. To protect the chilling-sensitive boar spermatozoa, holding the extended semen at a higher temperature before cooling could be beneficial and facilitate the implementation of the innovative preservation concept in practice, provided that bacterial growth is kept at a low level. The aim of this study was to introduce a holding time (HT) at 17°C before cooling and to examine the effect on sperm quality and bacterial growth compared to the original cooling protocol for antibiotic-free 5°C semen storage. A series of experiments with semen doses from eight boars extended in Androstar® Premium without conventional antibiotics revealed that sperm kinematics and the integrity of sperm plasma membranes and acrosomes were improved with HT between 16 and 24 h followed by delayed cooling with 0.04°C/min when compared to the original protocol for semen preservation at 5°C (p < 0.05). Both a shorter HT of 6 h and a faster cooling rate of 0.07°C/min reduced sperm quality (p < 0.05). The HT for 24 h did not compromise the inhibitory effect on bacterial growth during long-term semen storage at 5°C, not even in semen doses spiked with Serratia marcescens. In conclusion, semen storage at 5°C with the modified cooling protocol improved sperm quality and is antimicrobially efficient. It thus presents a ready-to-use tool for a reduction or replacement of antibiotics in pig insemination.