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.

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.

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.

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.

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 (β = - 0.32, p < 0.001). Additionally, the WQS models showed that the metal mixture may increase the risk of abnormal total motility (βWQS = 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.

Background: Worldwide, infertility affects about 15% of reproductive-age couples. In many cases, infertility can\'t be treated, however new treatment options with promising value have been involved in recent clinical trials. The aim of this clinical trial was to evaluate the impacts of adding coenzyme Q10 (CoQ10) to letrozole on the results of spermiogram and sex hormone tests in men diagnosed with idiopathic oligoasthenoteratozoospermia (iOAT) syndrome, which is a type of male defective spermatogenesis of unknown etiology. Methods: This randomized, open-label, parallel two-arm interventional study included 67 adult male patients aged 18-60 years with a confirmed diagnosis of iOAT syndrome recruited from The High Institute for Infertility Diagnosis & Assisted Reproduction Technologies/Nahrain University. Patients were randomly separated into two groups, Group A included 29 patients treated with letrozole 2.5 mg tablet orally twice a week, Group B included 38 patients treated with a combination of letrozole 2.5 mg tablet orally twice a week plus CoQ10 400 mg per day. Both groups completed treatment for three months. Semen samples, serum follicle-stimulating hormone (FSH), estradiol (E 2), and testosterone (T) were analyzed at day one, and at the end of month one, two and three. Results: Both groups showed that sperm concentration, normal morphology, total sperm count and motility, serum testosterone and FSH levels, and T/E 2 ratio were significantly increased, while estradiol levels significantly decreased after three months of treatment. Seminal fluid volume changed significantly in group A only. In comparing between the two groups, all measured parameters, apart from sperm motility and FSH level, demonstrated a significant difference after three months of treatment, while sperm volume reached significant value after only two months of therapy. Conclusions: CoQ10 as adjuvant treatment to letrozole effectively improved most of the tested sperm parameters in Iraqi men with iOAT. Registration: ClinicalTrials.gov ( NCT05847257, May 6, 2023).

BACKGROUND: The potential impact of diabetes mellitus type 1 (DM1) on male fertility is currently poorly defined. Hyperglycaemia and insulin deficiency may affect spermatogenesis. Some evidence suggests that men with DM1 have a significant reduction in progressive sperm motility, sperm morphology and semen volume, without significant changes in sperm concentration and count, but definite data are lacking.
OBJECTIVE: To evaluate the impact of DM1 on clinical parameters related to male fertility and semen analysis.
METHODS: We compared a court of 42 male DM1 patients with 43 nondiabetic subjects overlapping in age and remaining clinical data in an observational case-control study. All subjects underwent a comprehensive andrological reproductive evaluation, including medical history, physical examination, and semen analysis. We collected biochemical data in all patients with DM1, while diabetic patients with any alteration in semen parameters underwent sperm culture and scrotal ultrasound. In addition, all men completed the IIEF-5 questionnaire (International Index of Erectile Function-5) and the AMS (Aging Male Symptom score) questionnaire.
RESULTS: Patients with DM1 had a higher prevalence of infertility, erectile dysfunction and worse semen parameters compared with controls. In particular, semen volume, total sperm count, and total and progressive sperm motility were significantly lower (p < 0.001, p = 0.003, p = 0.048, and p = 0.022 respectively). In addition, the rate of semen anti-sperm antibody positivity, the AMS score and FSH levels were higher.
CONCLUSIONS: Several mechanisms may contribute to these semen alterations in DM1 patients, such as oxidative damage to spermatogenesis, seminal infections and pelvic neurological changes. These data suggest that patients with DM1 should be counselled from an andrological-reproductive point of view.

BACKGROUND: The WHO manual for basic semen analysis and ISO 23162 describe sperm morphology assessment as a standard part of semen analysis. Older studies showed a correlation between morphology results and (artificial) conception. In more recent studies this relationship was less apparent and there is more emphasis on sperm morphology as a marker for healthy spermatogenesis (and general male health). Meantime, many laboratories ceased morphology assessment, probably due to unfamiliarity with this paradigmatic shift and to technical difficulties in the assessment, like the interpretation of morphological criteria.
OBJECTIVE: The aim of this study was to identify morphological criteria with high variability in results in the Dutch External Quality Control (EQC) program.
METHODS: Over the period 2015-2020, a total of 72 photos of sperm cells along with dichotomous propositions based on 14 criteria as defined in WHO5 (2010) were distributed in the Dutch EQC program for semen analysis. The EQC results were evaluated for variability per criterion and for trends in time.
RESULTS: Between 2015 and 2020, 40 to 60 laboratories assessed the photos. Criteria with low variability between participants were related to acrosomal vacuoles, excessive residual cytoplasm, and tail metrics. In contrast, head ovality, regularity of head and midpiece contours, and alignment of the major axis of the midpiece and head led to the highest variability in outcomes. In general, there was a slightly positive trend (lower variability) in time, except for the criteria with the highest variability (stable or declining trend).
CONCLUSIONS: This study indicates that there are (high) variabilities in the interpretation of the morphological criteria, leading to inconsistent outcomes of morphology assessment. The results are discussed from the perspective of imperfections in definitions and examples of the criteria as given in the WHO manuals.

Artificial insemination (AI) centres select bulls as calves according to their genetic breeding values and raise them until the first semen collection; yet, a high dropout rate of reared bulls is a problem for AI centres. Potential hormonal indicators of bull sexual maturation (cortisol, dehydroepiandrosterone (DHEA), testosterone, oestradiol, insulin-like growth factor 1 (IGF-1)) were observed and evaluated in relation to the performance parameters to perhaps identify candidate biomarkers allowing an early selection of bulls as suitable sires. Blood samples from 102 German Holstein calves at 4 ± 1, 8 ± 1 and 12 ± 2 months of age from six AI centres were analysed using validated immunoassays for cortisol, DHEA, testosterone, oestradiol and IGF-1. Semen analyses included native and thawed diluted semen. Bulls were classified at the first semen collection into groups with good versus poor performance (GP vs. LP). After 2 years, the subsequent differentiation was done in high (HPP), medium (MPP) and low performance persistency (LPP). Age at first semen collection was an important factor for sperm quality. Cortisol concentrations decreased with age, but the cortisol/DHEA ratio decreased with age only in GP bulls (p < .05). Oestradiol and testosterone concentrations both correlated with libido behaviour (p < .05). Testosterone and IGF-1 concentrations were higher at the time of first semen collection in GP bulls and increased with age (p < .05). In conclusion, testosterone and IGF-1 concentrations at first semen collection are associated with performance at first semen collection and future performance persistency, and might be useful early biomarkers for consistent sperm producing bulls on AI centres.

This study aimed to investigate the protective effects of nanoparticle selenium (SeNP) and sodium selenite (SS) on preventing oxidative stress during the freezing process of dog semen. A total of six dogs were used in the study. The ejaculate was collected from dogs three times at different times by massage method. A total of 18 ejaculates were used and each ejaculate was divided in five experimental groups. The experimental groups were designed to tris extender containing no antioxidants control, 1 μg/mL SeNP1, 2 μg/mL SeNP2, and 1 μg/mL SS1 and 2 μg/mL SS2. Extended semen were equilibrated for 1 h at 4°C, then frozen in liquid nitrogen vapour and stored in liquid nitrogen (~-196°C). After thawing, semen samples were evaluated in terms of CASA motility and kinematic parameters, spermatozoa plasma membrane integrity and viability (HE Test), spermatozoa morphology (SpermBlue) and DNA fragmentation (GoldCyto). Antioxidant enzyme activity (glutathione peroxidase; GPX, superoxide dismutase; SOD, catalase; CAT) and lipid peroxidation (malondialdehyde; MDA) were evaluated in frozen-thawed dog sperm. When the results were evaluated statistically, the progressive motility, VCL, and VAP kinematic parameters in the SeNP1 group were significantly higher than the control group after thawing (p < .05). The highest ratio of plasma membrane integrity and viable spermatozoa was observed in the SeNP1 group, but there was no statistical difference found between the groups (p > .05). Although the ratio of total morphological abnormality was observed to be lower in all groups to which different selenium forms were added, compared to the control group, no statistical difference was found. Spermatozoa tail abnormality was significantly lower in the SeNP1 group than in the control and SS2 group (p < .05). The lowest ratio of fragmented DNA was observed in the SeNP1 group, but there was no statistical difference was found between the groups (p > .05). Although there was no statistical difference between the groups in the evaluation of sperm antioxidant profile, the highest GPX, SOD and CAT values and the lowest lipid peroxidation values were obtained in the SeNP1 group. As a result, it was determined that 1 μg/mL dose of SeNP added to the tris-based extender in dog semen was beneficial on spermatological parameters, especially sperm kinematic properties and sperm morphology, and therefore nanoparticle selenium, a nanotechnology product, made a significant contribution to the freezing of dog semen.