The effect of cigarette smoking on human seminal parameters,sperm chromatin structure and condensation

Considerable debate still exists regarding the effects of cigarette smoking on male fertility. This work aimed to explore effects of cigarette smoking on semen parameters and DNA fragmentation on 95 infertile patients who were divided into infertile male nonsmokers (45) and infertile male smokers (50). Smokers were subdivided according to a number of cigarettes smoked per day into mild (≤10), moderate (11‐20) and heavy smokers (≥21). Semen analysis, sperm chromatin condensation integrity with aniline blue staining and sperm viability were compared between the study groups. A significant decrease has been shown in sperm count (p = .006), progressive motility (p = <.001), percentage of normal forms (p = <.001) and viability (p = .002) between infertile nonsmoker and infertile smokers. The percentage of abnormal sperm chromatin condensation was significantly higher in smokers compared to nonsmokers (p = <.001). A linear correlation was detected between the extent of cigarette smoking and the degree of worsening in progressive motility (p = .001), total motility (p < .001), viability (p < .001) and normal morphology (p < .001). These results indicate that cigarette smoking has detrimental effects on semen parameters. It negatively affected all conventional semen parameters in addition to sperm chromatin condensation and sperm viability. These abnormalities were also proportional to the number of cigarettes smoked per day and to the duration of smoking.     

Sperm DNA fragmentation as a result of ultra‐endurance exercise training in male athletes

Intensive sports practice seems to exert negative effects on semen parameters; in order to assess these effects, the objective of this study was to assess semen, including DNA fragmentation, and hormone parameters in elite triathletes. Twelve high‐level triathletes preparing for a National Triathlon Championship participated in the study. The qualitative sperm parameters analysed were volume, sperm count, motility, morphology and DNA fragmentation; when needed, additional testing was performed. Assessed hormones were testosterone (T), cortisol (C) and testosterone–cortisol ratio (T/C). Maximum oxygen consumption and training characteristics were also assessed. Hormonal values and physical semen parameters were within normal ranges. DNA fragmentation showed high values (20.4 ± 6.1%). Round cells in semen were higher than normal (2.8 ± 1.5 million/ml), with the presence of macrophages. Correlations were found for several parameters: concentration of round cells positively correlated with progressive sperm motility (p = .01) and sperm morphology (p = .02); contrarily, the correlation found with DNA fragmentation was negative (p = .04). Sperm DNA fragmentation and the T/C ratio, however, were correlated in a positive manner (p = .03). As evidenced by the observed results, sperm DNA fragmentation is affected by high‐level sports practice; therefore, high loads of endurance training could potentially interfere with the athlete's fertility potential.     

Assessment of human sperm DNA integrity using two cytochemical tests: Acridine orange test and toluidine blue assay

Primary infertility affects approximately 15% of couples, with male factor infertility accounting for 50% of cases. Semen samples from 41 patients with asthenoteratospermia and 28 men with proven fertility were analysed according to World Health Organization guidelines. Abnormal sperm chromatin structure was assessed by toluidine blue assay (TBA), and DNA denaturation (DD) was detected by the acridine orange test (AOT). The mean (±SEM) rates of DD and abnormal chromatin structure were significantly higher in infertile subjects compared to fertile group respectively p = .003 and p < .001. A significant correlation was established between sperm DD and abnormal chromatin structure (R = .431, p < .001). Sperm DNA damage correlated significantly with abnormal morphology, sperm motility and necrozoospermia. Our study shows that men with increased levels of abnormal sperm chromatin structure have a high incidence of DNA denaturation and altered semen parameters. These findings suggest that male infertility has been linked to sperm DNA damage.     

Seminal plasma proteins and their relationship with sperm motility and morphology in boars

The identification of biomarkers associated with seminal traits could aid in the selection of higher quality ejaculates and benefit the swine industry. The objective of this study was to identify boar seminal plasma proteins associated with sperm motility and morphology. Twenty ejaculates from fifteen adult boars from a commercial boar stud were used for this work. After routine semen collection and analysis, ejaculates were classified into two groups: high‐quality semen (HQS) and low‐quality semen (LQS), based on sperm motility and morphology. Semen samples were processed for seminal plasma separation and analysis by 2D SDS‐PAGE. Total and progressive sperm motility differed between groups (p < 0.001), as well sperm morphology (p < 0.05). The intensity of spots identified as Major seminal plasma PSP‐I (PSP‐I) and cathepsin B (CTSB) was higher in LQS as compared to HQS samples (p < 0.05). Also, PSP‐I was positively associated with major and sperm cauda defects. Sperm motility was negatively correlated with both PSP‐I and cathepsin B. We conclude that high concentrations of Major seminal plasma PSP‐I and cathepsin B in boar seminal plasma are associated with reduced total and progressive sperm motility and low sperm morphology and might be used as biomarkers for semen quality.     

Age is a significant predictor of early and late improvement in semen parameters after microsurgical varicocele repair

Accumulating evidence indicates that varicocele repair improves sperm quality. However, longitudinal changes in sperm parameters and predictors of improved semen characteristics after surgery have not been fully investigated. We retrospectively reviewed data from 100 men who underwent microsurgical subinguinal varicocele repair at a single centre. Follow‐up semen examinations were carried out at 3, 6 and 12 months post‐operatively. Logistic regression was used to identify predictors of early (3 months) and late (≥6 months) improvement in semen parameters after varicocele repair. At 3 months post‐operatively, 76.1% of the patients had improved total motile sperm counts, which continued to improve significantly up to 12 months post‐operatively (p = .016). When comparing changes in semen parameters between younger (<37 years) and older (≥37 years) men, post‐operative improvements in sperm concentration and motility were greater among younger men. Multivariate analysis showed that younger age was associated with early (p = .043) and late (p = .010) post‐operative improvement in total motile sperm count. Our findings indicate that early varicocele repair improved semen parameters after surgery.     

Effect of modifiable lifestyle factors and antioxidant treatment on semen parameters of men with severe oligoasthenoteratozoospermia

Severe oligoasthenoteratozoospermia (OAT) refers to impaired count, motility and abnormal sperm morphology of infertile men associated with high chromosomal abnormalities. The objective of the present study was to define a management protocol for severe OAT cases and discover new routes to improve their basic semen parameters. We have applied a therapeutic treatment protocol in a cohort of 210 infertile men diagnosed with extreme severe idiopathic OAT. This therapeutic treatment based on modifying the lifestyle factors combined with antioxidant treatment for 6 months in severe OAT to study its effect on basic semen parameter. Basic semen parameters were assessed before and after applying the therapeutic treatment strategy. Sperm concentration, percentage of total motility and progressive motility were significantly increased after applying the therapeutic treatment (p = .006, p = .001 and p = .001 respectively). On the other hand, abnormal sperm morphology was significantly reduced after therapy (p < .01). In conclusion, the present results suggested that antioxidative supplement in combination with modifying the lifestyle factors in a cumulative treatment period significantly improves the basic semen parameters.     

Cystic fibrosis transmembrane conductance regulator is correlated closely with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters

Cystic fibrosis transmembrane conductance regulator (CFTR) has been demonstrated to be expressed in mature spermatozoa and correlated with sperm quality. Sperm CFTR expression in fertile men is higher than that in infertile men suffering from teratospermia, asthenoteratospermia, asthenospermia and oligospermia, but it is unknown whether CFTR is correlated with sperm parameters when sperm parameters are normal. In this study, 282 healthy and fertile men with normal semen parameters were classified into three age groups, group (I): age group of 20–29 years (98 cases, 27.1 ± 6.2), group (II): age group of 30–39 years (142 cases, 33.7 ± 2.6) and group (III): age group of more than or equal to 40 years (42 cases, 44.1 ± 4.6). Sperm concentration, total count and progressive motility were analysed by computer‐assisted sperm analysis. Sperm morphology was analysed by modified Papanicolaou staining. Sperm CFTR expression was conducted by indirect immunofluorescence staining. There was a significant positive correlation (P < 0.001) between CFTR expression and sperm progressive motility (r = 0.221) and normal morphology (r = 0.202), but there were no correlations between sperm CFTR expression and semen volume, sperm concentration, sperm total count as well as male age (P > 0.05). Our findings show that CFTR expression is associated with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters, but not associated with the number of spermatozoa and male age.     

Evaluation of the cryoprotective effect of seminal plasma on llama (Lama glama) spermatozoa

In South American camelids, sperm survival is low after thawing and poor results are obtained when artificial insemination is performed with cryopreserved semen. The aim of this study was to evaluate the effect of different percentages (10% and 50%) of seminal plasma added prior to the process of cryopreservation and also to evaluate the absence of seminal plasma on llama sperm survival after freezing and thawing. A total of 15 ejaculates from five adult llama males (n = 5; r = 3) were evaluated. A significant decrease in sperm motility, viability, membrane function and intact acrosomes was observed in thawed samples (0%, 10% and 50%) when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > 0.05), but a significant increase (p < 0.05) in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples compared to raw semen. Higher percentages of total and progressive sperm motility were observed when 0% and 10% of seminal plasma were used compared to 50%. However, no statistical differences were established for sperm viability, membrane function, morphology, acrosome status and DNA quality between thawed treatments. To conclude, neither of the percentages of seminal plasma used showed superiority nor cryoprotective effect on llama sperm survival.     

Impaired semen parameters in patients with confirmed SARS-CoV-2 infection: A prospective cohort study

In this prospective study, we investigated the impact of SARS-CoV-2 infection on semen parameters in a cohort of men who had recently recovered from COVID-19. A total of 24 men who had recently recovered from mild COVID-19 were included in the study. Their semen parameters were normal before COVID-19 according to the World Health Organization 2010 reference values. Semen samples were collected from these participants in the recovery phases of COVID-19. To determine the effect of SARS-CoV-2 infection on semen parameters, the patients' pre-COVID-19 and post-COVID-19 semen analyses were compared. The mean age of the participants was 34.7 ± 6.4 years. The median interval between the positive nasopharyngeal swab test and obtaining semen samples was 111.5 (158) days. There was no significant difference in semen parameters before and after COVID-19 in terms of semen volume (p = .56), sperm concentration (p = .06), and progressive motility (p = .14). Total motility (p = .01) and total motile sperm count (p = .02) decreased significantly after SARS-CoV-2 infection compared to the pre-infection values. This study demonstrated that sperm motility and total motile sperm count were the semen parameters which showed a significant reduction in cases with a history of mild COVID-19.     

Use of post‐thaw semen quality parameters to predict fertility of water buffalo (Bubalus bubalis) bull during peak breeding season

This study was designed to predict the fertility of water buffalo bull using post‐thaw semen quality parameters during peak breeding season. Thirty ejaculates were collected from five bulls with artificial vagina and cryopreserved. At post‐thaw, semen was analysed for motility parameters, velocity distribution, kinematics, DNA integrity/fragmentation, viability, mitochondrial transmembrane potential, morphology, plasma membrane and acrosome integrity. Data of 514 inseminations were collected for estimation of in vivo fertility. Pearson's correlation coefficients showed that progressive motility (PM), rapid velocity, average path velocity, straight line velocity, straightness, supravital plasma membrane integrity, viable spermatozoon with intact acrosome or with high mitochondrial activity were correlated with in vivo fertility (r = .81, p < .01; r = .85, p < .01; r = .64, p < .05; r = .73, p < .05; r = .57, p < .05; r = .88, p < .01; r = .84, p < .01 and r = .81, p < .01 respectively). Step forward multiple regression analysis showed that the best single predictor of fertility was PM. However, combinations of semen quality parameters to predict fertility were better as compared to single parameter. In conclusion, fertility of buffalo bull can be predicted through some of the post‐thaw in vitro semen quality tests during peak breeding season.     

Testicular thermoregulation,scrotal surface temperature patterns and semen quality of water buffalo bulls reared in a tropical climate

This study evaluated the capacity of thermoregulation and its consequences on the scrotal surface temperature patterns and semen quality of buffalo bulls raised in a wet tropical climate. Eleven water buffaloes were evaluated in the rainiest, in the transitional and in the less rainy season. Air temperature and humidity were consistently high, but the animals did not show thermal stress in any season. The scrotal temperature gradient of buffalo bulls using infrared thermography was described, and three parallel and decreasing thermal bands were characterised. Sperm quality (n = 176 ejaculates) was maintained in normal parameters over the periods. Pearson's coefficients showed that sperm volume and progressive motility were negatively correlated with ocular globe, epididymal tail and minimum scrotal temperatures (p < .01). Sperm membrane integrity was negatively influenced by increases in epididymal tail and minimum scrotal temperatures (p < .01). Ocular globe temperature also showed positive correlation with rectal, spermatic cord, and epididymal tail temperatures (p < .01). Therefore, even under high temperature and humidity, the thermoregulatory system was effective in preventing heat stress and the normality of scrotal surface temperatures, spermatogenesis and sperm maturation were maintained.     

Supplementing post-wash asthenozoospermic human spermatozoa with coenzyme Q10 for 1 hr in vitro improves sperm motility,but not oxidative stress

We investigated the effect of supplementing post-wash asthenozoospermic spermatozoa with coenzyme Q10 (CoQ10) in vitro, which may reduce oxidative stress and improve sperm motility. Semen samples were collected from 39 men with asthenozoospermia, and their spermatozoa were isolated by two-layer Percoll density-gradient centrifugation. Kinetic parameters of the isolated spermatozoa (baseline before intervention) were determined immediately by computer-aided semen analysis. Total anti-oxidant capacity and protein carbonyl levels, as markers of oxidative stress, were also measured in the baseline spermatozoa. The baseline spermatozoa suspension was divided equally into two portions, one for CoQ10 supplementation (50 µg/ml for 1 hr) and the other as an un-supplemented vehicle control. The total motility of the CoQ10-supplemented spermatozoa was significantly higher than in the control (p = .009) and progressive motility tended to be higher (p = .053). Immotile sperm concentration in the CoQ10-supplemented spermatozoa was significantly lower than in both the baseline (p = .026) and control (p = .009). Total anti-oxidant capacity and protein carbonyl levels between the baseline, CoQ10-supplemented and control spermatozoa were not significantly different. Our data suggest that CoQ10 treatment reactivated sperm motility. We propose short-term supplementation of post-wash asthenozoospermic spermatozoa with CoQ10 before intrauterine insemination.     

Famotidine does not affect human sperm fertility characteristics (motility,viability and DNA integrity) in vitro

Famotidine, a histamine‐2 receptor antagonist, is commonly used to relieve the acid‐related gastrointestinal diseases; however, its effect on human sperm parameters, and hence on sperm function, is still undetermined. Here, we intended to measure human sperm motility, viability, and DNA integrity of ejaculated human sperm in the presence of famotidine at 0, 0.1, 1 and 10 mM concentrations in vitro. Forty‐nine semen samples of normal count, motility, and morphology were included in this study. Sperm motility was assessed using Makler counting chamber and a phase contrast optics (200× magnification), whereas sperm viability was assessed using eosin–nigrosin staining procedure. The effect of famotidine on sperm DNA integrity was measured using flow cytometry. Famotidine at 0.1, 1 or 10 mM had insignificant effect on human sperm motility (progressive, p = .9594; and total, p = .8420), sperm viability (p = .6471), and content of DNA breaks in sperm (p > .05) compared with the control. In conclusion, famotidine at 0.1, 1 or 10 mM did not alter human sperm motility, viability or DNA integrity in vitro. Although, these findings indicate safety of famotidine in human sperm, further in vivo studies are required to establish the drug's safety.     

The impact of sociodemographic characteristics,lifestyle, work exposure and medical history on semen parameters in young Chinese men: A cross‐sectional study

There is an ongoing debate on the declining semen quality, and unfortunately, existing evidence is inconclusive and inconsistence. We evaluated the impact of sociodemographic characteristics, lifestyle, medical history and work exposure on semen quality. Univariate and multivariate analysis was used to investigate the association between different risk factors and semen quality parameters. Total sperm count (p = 0.041), sperm concentration (p = 0.007), normal morphology (p = 0.002), total motility (p = 0.004) and progressive motility (p = 0.009) decreased in men with varicocele. Sperm concentration increased in tea (p = 0.044); progressive and total motility increased in cola (p = 0.018, p = 0.012) consumers. Progressive and total motility decreased in urogenital surgery (p = 0.016, p = 0.014) and infection (p = 0.037, p = 0.022). However, age, coffee and alcohol drinking, physical activities, sleep duration and cell phone use were unrelated to any of semen parameters. Interestingly, semen volume (p < 0.0001), total sperm count (p < 0.0001) and concentration (p < 0.033) increased with longer abstinence period (>5 days); normal morphology (p = 0.013) improved in men with higher body mass index (BMI > 24), curvilinear velocity (p = 0.042) increased with smoking; semen volume (p = 0.050) increased in manual labourers. This study highlights the importance of sociodemographic characteristics, lifestyle, occupational exposure and medical history and provides time trends in semen quality, its clinical importance and direction for further research.     

Assessment of sperm hyperactivated motility and acrosome reaction can discriminate the use of spermatozoa for conventional in vitro fertilisation or intracytoplasmic sperm injection: Preliminary results

Basic semen analysis is insufficient for determining the fertility potential. The aim of this study was to determine if hyperactivated motility (HAM) and acrosome reaction (AR) can be useful tests for evaluating semen quality during male infertility evaluations and to help the clinician decide whether regular insemination or intracytoplasmic sperm injection (ICSI) is preferable during in vitro fertilisation. A prospective study was conducted. Patients with normal sperm according to World Health Organization guidelines who underwent IVF treatment and planned regular insemination were asked to participate. A portion of sperm sample was evaluated for HAM and AR on day of ovum pick up. In HAM assessment, 93.3% of patients with increased HAM had a high fertilisation rate compared with 64% in the group without increased HAM (P = 0.059). For the AR evaluation, 91.7% of samples with a low rate of spontaneous AR had a high fertilisation rate compared with 39.3% in the group with a high rate of spontaneous AR (P = 0.004).     

Sperm nuclear DNA fragmentation and its association with semen quality in Greek men

Due to the limitations of conventional semen analysis in predicting a man's fertility potential, sperm DNA fragmentation was recently introduced as a novel marker of sperm quality. This prospective study was undertaken to investigate the associations between conventional seminal parameters and DNA fragmentation in Greek men. A total of 669 subject data were evaluated in two groups, normozoospermic (n = 184) and non‐normozoospermic (n = 485), according to the WHO 2010 (WHO Laboratory Manual for the Examination and Processing of Human Semen, 5th edn. World Health Organization), reference limits. For all the subjects, semen volume, sperm concentration, total count, rapid and total progressive motility and morphology were recorded following the WHO 2010 methods and DNA fragmentation was assessed by the sperm chromatin dispersion assay. An inverse correlation was established between DNA fragmentation and all conventional seminal parameters except semen volume in men with seminal profiles below the reference limits, with statistical significance for rapid and total progressive motility. Normozoospermic men exhibited lower levels of DNA fragmentation than their non‐normozoospermic counterparts, even though the values were not always below 30%. DNA fragmentation testing and traditional semen analysis should therefore be considered as complementary diagnostic tools in a comprehensive evaluation of male infertility.     

Incubation of frozen-thawed llama sperm with seminal plasma

Seminal plasma is intimately connected to sperm physiology and particularly in South American Camelids, has demonstrated to be involved in multiple physiological reproductive events. Different percentages of seminal plasma (0%, 10% and 50%) were added to thawed llama semen samples with the objective of evaluating the interaction with cryopreserved sperm over time (0, 1.5 and 3 hr at 37°C). A total of 20 ejaculates from five adult llama males (n = 5; r = 4) were evaluated. A significant decrease in sperm motility, membrane function and live sperm was observed in all thawed samples (0%, 10% and 50%) at 0 hr when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > .05), but a significant increase in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples versus raw semen. When evaluating thawed samples over time, a significant decrease of motility and membrane function was observed, while the percentages of total live sperm were preserved over the 3 hr of incubation in all final concentrations evaluated. To conclude, the addition of 10% or 50% of seminal plasma was incapable of preserving motility or membrane function of frozen-thawed llama sperm during 3 hr of incubation.     

Assessment of seminal mast cells in infertile men with varicocele after surgical repair

This study aimed to assess seminal mast cells in infertile men associated with varicocele (Vx) pre‐ and post‐surgical repair. Forty‐five infertile men associated with Vx were subjected to history taking and clinical examination. In addition, semen parameters and seminal mast cells stained with 1% toluidine blue were estimated pre‐varicocelectomy and three months post‐varicocelectomy. Vx surgical repair revealed a significant improvement in the mean sperm concentration, progressive sperm motility, total sperm motility and sperm abnormal morphology and a significant decrement in seminal mast cells (mean ± SD, 3.56 ± 2.23 cells per high‐power field (HPF) vs. 2.22 ± 1.06 cells per HPF, p = .01). The pre‐operative mean mast cell count demonstrated significant increases in cases with Vx grade III compared with other Vx grades and in cases with bilateral Vx compared with unilateral Vx cases. Seminal mast cells demonstrated a significant correlation with sperm concentration, progressive sperm motility and total sperm motility and a nonsignificant correlation with age and sperm abnormal morphology. It is concluded that seminal mast cells decrease significantly in infertile men with Vx after surgical repair showing a significant negative correlation with sperm concentration, progressive sperm motility and total sperm motility.     

Essential oils rich in monoterpenes are unsuitable as additives to boar semen extender

Despite the development of efficient boar semen extenders, there is still room for improvement of new formulas using new molecules that could increase fertilisation outcomes and substitute cryoprotectants and antibiotics. The goal of this work was to evaluate if the essential oils from the leaves of Myrrhinium atropurpureum and Cymbopogon citratus are suitable as additives in boar semen extender. The major compounds found in the essential oils from M. atropurpureum were 1,8‐cineole (37.37%) and terpinolene (19.18%); and geranial (49.8%) and neral (33.24%) in essential oil of C. citratus. The addition of 1% and 0.1% of both essential oils to extended semen had immediate spermicidal effects (p < 0.05). Lower concentrations were tested and no cytotoxic effect was observed when M. atropurpureum essential oil was added at 0.001%. Differently, essential oil from C. citratus reduced sperm motility, membrane functionality and integrity and mitochondrial membrane potential even in concentrations as low as 0.001%. Also, addition of essential oils in low concentrations had no inhibitory effect against Escherichia coli and Pseudomonas aeruginosa growth. We conclude that the essential oils from C. citratus and M. atropurpureum, rich in monoterpenes, are cytotoxic to swine spermatozoa, therefore unsuitable as semen extender additives.     

Semen quality in adult male survivors 5 years after the 2008 Wenchuan earthquake

The influence of the Wenchuan earthquake on semen quality of adult male survivors is unclear. We investigated the semen quality included 673 male survivors from the worse‐affected counties in the earthquake between Aug 2008 and July 2013. Semen parameters including pH, volume, concentration, motility and morphology were measured according to the World Health Organization (WHO) criteria. Kruskal–Wallis analysis of variance was used to examine the statistical differences between years, and a logistic regression was used to analyse the impacts caused by earthquake on the changes of semen quality. We found the medians (5th and 95th) were 2.5 ml (0.6–5.5) for semen volume, 59.0 × 10⁶ ml^?1 [(13.0–133.0)] × 10⁶ ml^?1 for semen concentration, 46% (13–64%) for sperm progressive motility and 3.0% (0–17.5%) for normal morphology for adult male survivors. Semen concentration, the percentage of sperm progressive motility, total motility and sperm normal morphology were all decreased in the first 3 years, and the differences among years 1, 2 and 3 were significant except the percentage of sperm progressive motility (P < 0.05). The casualties and heavy housing damage caused by earthquake had a negative effect on semen quality. The main findings will provide further diagnosis and therapy basis of male fertility by data, for affected populations in the earthquake.