Exploring the relationship between ambient sulfur dioxide and semen quality parameters:A systematic review and meta-analysis

Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality parameters.Methods:A systematic literature search was conducted to identify relevant studies investigating the association between SO2 exposure and semen quality parameters.This search encompassed the timeframe from January 2000 to May 2023 and included electronic databases such as Web of Science,Google Scholar,PubMed,Cochrane,and Scopus.Pooled effect estimates with 95%confidence intervals(CI)were calculated using percent changes(PC).The meta-analysis included seven studies with 6711 participants and 15087 semen samples.Results:The results revealed a significant negative association between ambient SO2 exposure and certain semen quality parameters.In particular,SO2 exposure was associated with a significant decrease in progressive motility(PC=0.032;95%CI:-0.063 to-0.001;P=0.044)and sperm concentration(PC=-0.020;95%CI:-0.036 to-0.005;P=0.012).However,no statistically significant associations were observed for total sperm count(PC=-0.038;95%CI:-0.079 to 0.003;P=0.070),seminal fluid volume(PC=-0.009;95%CI:-0.048 to-0.030;P=0.662)and sperm motility(PC=-0.17;95%CI:-0.363 to 0.022;P=0.830).In addition,the results of the subgroup analysis revealed specific variables that were associated with the decrease in relevant sperm parameters.Conclusions:This systematic review and meta-analysis provides compelling evidence supporting a consistent negative association between exposure to ambient SO2 and semen quality parameters.

Seasonal stress on semen quality profiles, seminal biochemical and oxidative stress attributes in endangered Teressa goat of Andaman and Nicobar Islands

Objective:To measure seasonal effects on semen quality profiles,seminal biochemical and oxidative stress attributes in fresh and liquid stored semen in monsoon and dry seasons.Methods:A total of 10 Teressa bucks(3-4 years)were selected from breeding farm,ICAR-Central Island Agricultural Research Institute,Port Blair,Andaman and Nicobar Islands,India.Semen samples(n=25 per season)were collected through artificial vagina method and preserved at refrigerated temperature(5℃)for 48 h using Tris citrate glucose based extender.We detected semen quality parameters[volume,mass activity,pH,sperm concentration,total motility,viability,total sperm abnormality,and plasma membrane,acrosomal and nuclear integrities],biochemical profiles[aspartate amino transferase(AST),alanine amino transferase(ALT)and total cholesterol],and oxidative stress markers[total antioxidant capacity(TAC)and malondialdehyde(MDA)]during monsoon and dry seasons.Results:Semen quality parameters significantly differed between seasons(P<0.05)and among storage periods(P<0.05).Volume,pH,mass activity,motility,viability,acrosomal,plasma membrane and nuclear integrities,and TAC were significantly higher(P<0.05).Sperm concentration,sperm abnormalities,MDA,AST,ALT and total cholesterol were significantly lower in fresh semen of monsoon than dry season(P<0.05).Motility,viability,acrosomal,plasma membrane and nuclear integrities,and TAC were significantly decreased(P<0.05)while sperm abnormality,AST,ALT,total cholesterol and MDA were significantly increased as liquid semen storage period advanced(P<0.05).Conclusions:Monsoon season has higher beneficial effects on semen quality profiles and liquid stored semen remained usable for upto 48 h.Good quality ejaculates with higher TAC and lower MDA can be cryopreserved and will be used for artificial insemination.

Lifestyle: an underrated but potentially important influencing factor on semen quality

Lifestyle factors play a crucial role in the influence of semen quality,and they are especially significant in the context of traditional Chinese medicine(TCM)clinical treatment for poor semen quality.TCM theory emphasizes the importance of healthy lifestyle habits for overall well-being.Therefore,it is essential to consider lifestyle factors in the clinical management of TCM and semen quality.Lifestyle can act as a bias factor that affects research quality,making it vital to pay special attention to its impact in clinical trial research on male semen quality.This article aims to improve the quality and design of clinical research on male sperm quality by examining the effects of various lifestyle factors on semen quality,including physical activities,dietary patterns,smoking,alcohol consumption,coffee intake,sleep,and psychological stress.Each lifestyle factor has its own distinct influence on semen quality,and there is a synergistic effect when multiple lifestyle factors are combined.These findings emphasize the need for careful consideration of lifestyle factors and their interactions in the design and implementation of TCM clinical trial research.

Natural astaxanthin enhanced antioxidant capacity and improved semen quality through the MAPK/Nrf2 pathway in aging layer breeder roosters

Background:Natural astaxanthin(ASTA)has strong antioxidant properties and has been widely used as a health product to improve human health.However,the effects of ASTA on the reproductive performance of aging roosters have been poorly studied.We aimed to investigate the effects of dietary ASTA on semen quality and antioxidant capacity in aging roosters and to explore the potential mechanism of semen quality change via antioxidation defense system.Methods:In the present study,9653-week-old Jinghong No.1 layer breeder roosters were fed a corn-soybean meal basal diet containing 0,25,50,or 100 mg/kg ASTA for 6 weeks.Results:Semen quality in the ASTA groups remarkably improved than that in the control group,and antioxidant activities,the abilities to scavenge hydroxyl radicals and superoxide anions,increased gradually with ASTA addition(P<0.05).In addition,the mRNA levels of antioxidant enzymes as well as the mRNA and protein levels of the mitogen-activated protein kinase(MAPK)and nuclear factor-erythroid 2-related factor 2(Nrf2)were markedly increased in the 50-100 mg/kg ASTA group(P<0.05).Conclusions:Collectively,these results demonstrate that dietary ASTA may improve semen quality by increasing antioxidant enzyme activities and the ability to scavenge hydroxyl radicals,which may be related to upregulation of the MAPK/Nrf2 pathway.

Taurine in semen extender modulates post–thaw semen quality,sperm kinematics and oxidative stress status in mithun(Bos frontalis)spermatozoa

Objective:To assess the effect of taurine on post-thaw semen quality parameters,sperm kinematics,antioxidant and oxidative stress profiles and sperm cholesterol efflux in mithun(Bos frontalis).Methods:A total of 50 ejaculates(n=25 samples)were selected based on biophysical parameters.Each sample was split into four equal aliquots after dilution with the Tris-citrate-glycerol extender.GroupⅠ,Ⅱ,ⅢandⅣcontained 0 mM(the control),25 mM,50 mM and 100 mM of taurine,respectively.Frozen-thawed samples were analysed for motility parameters(progressive forward and in bovine cervical mucus penetration test),kinetic and velocity parameters by computer-assisted sperm analyzer,viability,sperm and nuclear abnormalities,acrosome integrity,plasma membrane and nuclear integrities,sperm enzymatic leakage and biochemical(sperm cholesterol and oxidative stress)profiles.Results:The extender containing 50 mM taurine led to a significant enhancement in viability,acrosomal integrity,plasma membrane integrity,motility(progressive and in cervical mucus),and sperm cholesterol content and notably reduced sperm morphological and nuclear abnormalities,and leakage of intracellular enzymes compared to other taurine treated and untreated control groups(P<0.05).Moreover,in addition to significant improvement in kinetic and velocity profiles,50 mM taurine protected the integrity of acrosome and biochemical membranes than in the untreated control and other taurine treated groups.Inclusion of 50 mM taurine held a clear advantage over the control or 25 mM or 100 mM taurine in cryopreservation of mithun semen.Conclusions:Taurine(50 mM)supplementation in semen extender can be effectively utilized to reduce oxidative stress and improve post-thaw semen quality in mithun.

Adding chitosan nanoparticles of green tea extract in diluent and thawing temperatures ameliorate the post-thawed quality of Boer buck semen

Objective:To improve the quality of post-thawing Boer buck semen for artificial insemination by adding green tea extract chitosan nanoparticles to skimmed egg yolk diluent,and the proper thawing temperature.Methods:The ejaculate of Boer buck was added to skimmed egg yolk diluent without(the control group)and with adding 1μg of chitosan nanoparticles of green tea extract per mL of diluent(the treatment group).Then,the diluted semen was filled in French mini straws containing 60×106 live sperm per straw,frozen in a standard protocol,and stored as frozen semen at−196℃for a week.Six replicates from each group were diluted for 30 s at 37℃or 39℃sterile water to evaluate the semen quality.Results:Post-thawing(at 37℃or 39℃)of live sperm,progressive motility,and plasma membrane integrity were lower compared to those of the pre-freezing stage(P<0.05).Thawing at 37℃resulted in no significant difference in live sperm,progressive motility,and plasma membrane between the control group and the treatment group(P>0.05).The live sperm,progressive motility,and plasma membrane of the treatment group in the pre-freezing stage,and post-thawed at 39℃were higher compared to those of the control group(P<0.05).There was no significant difference in malondialdehyde(MDA)concentration,DNA fragmentation,and catalase concentration of thawing at 37℃compared to those of 39℃in the same group.The MDA concentration and DNA fragmentation in thawing at 37℃and 39℃of the treatment group were significantly lower than those of the control group(P<0.05).However,the catalase concentration in thawing at 37℃and 39℃of the treatment group was not significantly different than the control group(P>0.05).Conclusions:Higher quality post-thawing Boer buck semen is achieved by adding 1μg/mL of chitosan nanoparticles of green tea extract to the skimmed egg yolk diluent and thawing at 39℃.

The Effects of Age and Ejaculatory Abstinence on Semen Quality and Reproductive Hormones in Africa and the Middle East

The aim of this study was to retrospectively evaluate the effects of male age and ejaculatory abstinence on semen parameters and reproductive hormones among men residing in Africa and the Middle East. A total of 70,142 semen analysis results were analysed and grouped according to the age intervals (16 - 20, 21 - 30, 31 - 40, 41 - 50, 51 - 60, >60) and ejaculatory abstinence (<2 days, 2 - 5 days and >5 days). Semen parameters i.e. volume, concentration, progressive motility, total progressively motile count, morphology, total normal sperm count, DNA fragmentation, viability, sORP, normed sORP were specifically evaluated. Additionally, for each age interval, reproductive hormones i.e. estradiol, luteinizing hormone, follicle stimulating hormone, testosterone and prolactin were evaluated. Semen volume, total progressively motile count, sperm morphology and total normal sperm count constantly decrease significantly after the age of 30 years. Sperm concentration started declining significantly after the age of 50 years. There was a constant age- related increase in number of spermatozoa with damaged DNA. sORP constantly increased up to 60 years. Furthermore, constantage-related decreases in FSH, serum testosterone and prolact in were observed from patients aged between 16 years and 60 years. Semen volume, sperm concentration, progressive motility and normal morphology were significantly higher in patients having > 5 days of abstinence. Patients having > 5 days of abstinence had the lowest normed sORP. Male age significantly affects sperm parameters and reproductive hormones in fertile and infertile men residing in Africa and the Middle East. Prolonged abstinence days provides better semen quality.

Will male semen quality improve with environmental quality?

Wenzhou has improved its environmental quality because of comprehensive environmental remediation;nevertheless,the semen quality of infertile males remains unclear.This study determined whether better environmental quality improved semen quality in this region.We recorded semen quality data from 22962 infertile males from January 2014 to November 2019 at the Center for Reproductive Health of The First Affiliated Hospital of Wenzhou Medical University(Wenzhou,China).Patients were predominantly 30–35 years old(33.1%)and workers(82.0%),with high school education or lower(77.6%);more than a half of the patients(52.6%)were Wenzhou household registration;and most patients(77.5%)had abnormal semen quality.Patients who were older than 40 years and workers,and those with Wenzhou household registration,had significantly worse semen quality(all P<0.05).From 2014 to 2019,progressive sperm motility,total sperm motility,and semen volume showed increasing linear trends in all patients(P=0.021,0.030,and 0.005,respectively),yet normal sperm morphology showed a linearly decreasing trend(P=0.046).Sensitivity analyses for subgroups yielded similar results.In conclusion,the improvement of environmental quality and better function of the accessory glands are associated with progressive sperm motility,total sperm motility,and semen volume.Normal sperm morphology is influenced by occupational exposures and personal lifestyle and does not improve with environmental quality.

Analysis of semen quality of 38 905 infertile male patients during 2008- 2016 in Wenzhou, China

This study analyzed the trend in semen quality of infertile male patients in Wenzhou,China,based on the data obtained from 38905 patients during 2008-2016 in The First Affiliated Hospital of Wenzhou Medical University(Wenzhou,China).The results showed that only 24.9%of the patients had normal semen quality.For the semen quality of infertile male patients,that of the workers and 40-year-olds was significantly worse than the other occupational and age groups.For all the infertile patients,low semen volume,asthenozoospermia,and teratozoospermia accounted for 8.4%,50.5%,and 54.1%,respectively.During 2008-2016,the annual mean percentage of fast forward motile spermatozoa,percentage of total forward motile spermatozoa,and percentage of spermatozoa with normal morphology decreased linearly with slopes of-2.11,-2.59,and-0.70,respectively.The proportion of patients with asthenozoospermia and multi-abnormal spermatozoa increased during 2008-2016 with slopes of 4.70 and 4.87,respectively,while for low semen volume,it decreased with a slope of-0.47 in the same time period.The proportion of patients with teratozoospermia increased from 2008 to 2011 and from 2011 to 2016 with slopes of 17.10 and 2.09,respectively.In general,the deteriorating trend of semen quality of infertile male patients in Wenzhou was obvious.Future efforts should be made to reveal the adverse influences on semen quality,such as occupational exposure,environmental quality,and living habits.Furthermore,more pervasive reproduction health education is necessary.

Environmental exposure to cadmium but not lead is associated with decreased semen quality parameters:quality regionalism of sperm properties

Environmental factors may negatively contribute to a progressive worsening of semen quality,and differences in semen quality may result from different environmental exposures(regional differences)or lifestyle differences.Heavy metals are factors with a confirmed negative influence on male fertility.Among them,lead and cadmium are commonly found in human surroundings.Thus,we analyzed semen parameters(according to the World Health Organization 2010 recommendations)and semen lead and cadmium concentrations in 188 men from two different regions in Poland,a typical agricultural area and an industrial area,in couples that had been diagnosed with infertility.The assays were performed using flameless electrothermal atomic absorption spectrometry.In the statistical analysis,regional comparisons and then taxonomic comparisons based on three parameters(age,semen concentration,and sperm morphology)were applied.We showed that more cadmium than lead accumulated in semen,a higher cadmium concentration was observed in semen obtained from men from the agricultural region,and better semen quality and lower cadmium concentrations were found in the semen of men from the industrial,more polluted region.We thus showed an existing regionalism in the sperm quality properties.However,semen parameters such as morphology and progressive and nonprogressive motility followed the same trends,regardless of the patient’s age,region,or class.We could conclude that the environment has a minor impact on sperm morphology and progressive and nonprogressive motility and that other existing factors could have an indirect influence on semen quality.

The effect of healthy dietary patterns on male semen quality:a systematic review and meta-analysis

The incidence of infertility has recently risen.Semen quality is an important male fertility indicator,and dietary factors can affect semen quality.We conducted this systematic review and meta-analysis to determine the effects of healthy dietary patterns on semen quality.A literature search was conducted in 3 databases(Embase,Web of Science and PubMed)on August 21,2021.The included cross-sectional studies examined the influence of the Mediterranean,Dietary Approaches to Stop Hypertension(DASH),and prudent diet patterns on semen quality parameters;six studies(1244 subjects)were included.By comparing high consumption with low consumption of healthy dietary patterns,the results of the meta-analysis showed significantly higher sperm concentrations(mean difference[MD]=6.88×10^(6) ml^(−1),95%confidence interval[CI]:1.26×10^(6) ml^(−1)–12.49×10^(6) ml^(−1);P<0.05),a significant increase in total sperm count(MD=16.70×10^(6),95%CI:2.37×10^(6)–31.03×10^(6);P<0.05),and a significant increase in progressive sperm motility(MD=5.85%,95%CI:2.59%–9.12%;P<0.01).The sperm concentration,progressive sperm motility,and total sperm count were significantly higher in men with higher versus lower consumption of healthy dietary patterns.However,the results must be interpreted with caution.

Sperm Quality and Environment: A Retrospective, Cohort Study among 21,715 Semen Samples in a Southern Province of China

To explore the differences of male semen parameters in different seasons of the year, so as to explore the potential climatic factors affecting spermatogenesis and male reproductive ability, we retrospectively analyzed 21,715 semen analysis data from January 2018 to February 2021, grouped by year and season, and finally the relationships among semen parameters and semen and meteorological parameters were compared. Environmental exposures prior to 3 months were analyzed and correlation analysis was performed.The semen concentration decreased year by year (p < 0.01). However, the Progressive motility (PR) and total PR number had been increased (p < 0.01). There were statistical differences in sperm parameters which include semen volume, sperm concentration, total sperm number, progressive motility (PR), total PR number and total motility in different seasons, winter and spring were better than summer and autumn (p < 0.01). Total sperm number and sperm concentration were positively correlated with PR (R = 0.420, R = 0.440, p < 0.01). There was no correlation between daylight duration and semen parameters. Sperm parameters were positively or negatively correlated with environmental temperature, air pressure or humidity which had an overall effect on semen quality. It is suggested that seasonal factors should be considered when evaluating male reproductive ability. Besides referring to conventional semen parameters, other factors such as season and climate should also be considered.

Fertility Reduction in Male Persian Fallow Deer (Dama dama mesopotamica): Inbreeding Detection and Morphometric Parameters Evaluation of Semen

Persian fallow deer (Dama dama mesopotamica) is only found in a few protected and refuges areas in the northwest, north, and southwest of Iran. The aims of this study were analysis of inbreeding and morphometric parameters of semen in male Persian fallow deer to investigate the cause of reduced fertility of this endangered species in Dasht-e-Naz National Refuge, Sari, Iran. The Persian fallow deer semen was collected by an electroejaculator from four adult bucks randomly during the breeding season and from five dehorned and horned deer’s in non-breeding season. Twelve blood samples were taken and mitochondrial DNA was extracted, a non-coding region called d-loop was amplified, sequenced and then were considered for genetic analysis. The Persian fallow deer’s normal and abnormal spermatozoa were similar to that of domestic ruminants but very smaller and difficult to observe at the primary observation. The post-mating season collected ejaculates contained abnormal spermatozoa, debris and secretion of accessory glands in horned bucks and accessory glands secretion free of any spermatozoa in dehorned or early velvet budding bucks. Microscopic evaluation in all four bucks during the mating season showed the mean concentration of 9 × 106 spermatozoa/ml. The mean ± standard deviation of age, testes length and testes width was 4.60 ± 1.52 years, 3.58 ± 0.32 and 1.86 ± 0.09 cm, respectively. The results identified 1120 loci in which 377 were polymorphic. In conclusion, reduced fertility of male Persian fallow deer may be caused by inbreeding of the protected herd in a limited area of Dasht-e-Naz National Refuge.

Bacteriospermia among smallholder artificial insemination boars in the Philippines and potential associated factors

Objective:To determine the prevalence of bacteriospermia,the bacterial load,and the potential factors associated with bacterial contamination in boar semen collected by local smallholder artificial insemination operators.Methods:Fifteen individual raw semen samples were collected from locally available artificial insemination boars owned by different smallholder boar operators within the 5th district of Leyte,Philippines and were subjected to standard bacteriological culture and identification,including a survey of potentially associated factors.Prevalence and bacterial count were determined accordingly,while boar characteristics and collection practices were clustered following agglomerative hierarchical clustering technique.Results:One hundred percent contamination with a bacterial count of(2.01±0.38)×10^(3) CFU/mL was observed.At least 73.33%of the samples were positive for Bacillus spp.,while other identified isolates included Enterobacter spp.,Staphylococcus spp.,E.coli,Pseudomonas spp.,Citrobacter spp.,and Klebsiella spp.Conclusions:Despite the high prevalence of bacteriospermia,the bacterial count is low.Nevertheless,on-farm practices on boar health and management,semen collection,and sanitation as well as the enhancement of basic protocols to control contamination should be conscientiously considered in smallholder artificial insemination operation.

Oxytocin in pig seminal plasma is positively related with in vivo fertility of inseminated sows

Background:Identification of relevant in vivo biomarkers for fertility remains a challenge for the livestock industry.Concentrations of the small peptide hormone oxytocin(OXT),involved in male reproductive function and present in the seminal plasma(SP)of several species could be a robust one.This study characterized concentrations of SPOXT in ejaculates from boars used in artificial insemination(AI)programs aiming to evaluate its relationship with sperm quality variables and in vivo fertility of their liquid-stored AI-semen.Seminal OXT concentrations(ng/mL)were measured in 169 ejaculates from 61 boars of the Duroc,Pietrain,Landrace and Large White breeds using a direct competitive immunoassay test based on AlphaLISA®technology.Ejaculate(ejaculate volume,sperm concentration,total sperm count)and sperm parameters(motility,viability,intracellular generation of reactive oxygen species,plasma membrane fluidity)were assessed at 0 h and 72 h in AI-semen samples stored at 17℃.In vivo fertility included only 18 Large White and Landrace boars whose AI-semen was used to inseminated>100 sows and evaluated both farrowing rate and litter size of 3,167 sows.Results:The results showed that SP-OXT differed between boars and between ejaculates within boar(P<0.05)but not between breeds(Duroc,Pietrain,Landrace and Large White).Ejaculates with higher SP-OXT concentration/mL(hierarchically grouped;P<0.001)had larger volume and came from younger boars(P<0.05).Ejaculates of boars showing positive farrowing rate deviation exhibited higher(P<0.05)SP-OXT concentration/mL than those with negative farrowing rate deviation.Conclusion:The SP concentrations of OXT are boar,ejaculate and age dependent,and positively related with ejaculate volume and farrowing rates of liquid-stored semen AI-doses.

Association of Lifestyle Factors and Sperm Motility in Adults from an Ethnic Minority Region of Southwest China

Objectives: To understand sperm motility in adults and its association with lifestyle in an ethnic minority area in Southwest China. Methods: A hospital-based cross-sectional study to assess sperm motility in male adults was conducted at the Reproductive Health Center from January 2018 to May 2019. The data was collected with a questionnaire and semen quality was analyzed with Computer-Aided Sperm Analysis system (CASA). Analysis of covariance (ANCOVA) was used to measure the relationship between lifestyle factors and sperm motility. Results: A total of 349 people were recruited. Dietary celery intake was significantly related to the increase of sperm progressive motility and total motility (β = 7.00, 95% CI: 1.59, 12.42 and β = 7.26, 95% CI: 1.45, 13.07, respectively). Cola consumption was associated with increased sperm progressive motility (β = 9.71, 95% CI: 1.46, 17.96). Frequent use of plastic bags for meat food storage (β = -5.56, 95% CI: -10.61, -0.51), industry work (β = -5.64, 95% CI: -11.21, -0.07), organic disease (β = -6.14, 95% CI: -11.00, -1.28) and sedentary lifestyle (β = -5.92, 95% CI: -10.66, -1.17 for 3-5 h/d and β = -6.04, 95% CI: -11.60, -0.47 for ≥5 h/d, respectively) were related with the decreased sperm progressive motility. Meanwhile, using plastic bags for meat food storage (β = -6.37, 95% CI: -11.79, -0.95), industry work (β = -7.96, 95% CI: -13.94, -1.98) and sedentary lifestyle (β = -5.51, 95% CI: -10.60, -0.42 for 3-5 h/d and β = -6.03, 95% CI: -12.01, -0.06 for ≥5 h/d, respectively) were also risk factors for total motility. Conclusions: Some modifiable lifestyle factors such as job title, cola consumption, dietary celery intake, plastic bags for meat food storage, and sedentary hours were linked to male sperm motility, indicating that changing these lifestyles may improve it.

Association between semen collection time and semen parameters:an observational study

The process of semen collection plays a key role in the quality of semen specimens.However,the association between semen collection time and semen quality is still unclear.In this study,ejaculates by masturbation from 746 subfertile men or healthy men who underwent semen analysis were examined.The median(interquartile range)semen collection time for all participants was 7.0(5.0-11.0)min,and the median time taken for semen collection was lower in healthy men than that in subfertile men(6.0 min vs 7.0 min).An increase in the time required to produce semen samples was associated with poorer semen quality.Among those undergoing assisted reproductive technology(ART),the miscarriage rate was positively correlated with the semen collection time.After adjusting for confounders,the highest quartile(Q4)of collection time was negatively associated with semen volume and sperm concentration.A longer time to produce semen samples(Q3 and Q4)was negatively correlated with progressive and total sperm motility.In addition,there was a significant negative linear association between the semen collection time and the sperm morphology.Higher risks of asthenozoospermia(adjusted odds ratio[OR]=2.06,95%confidence interval[CI]:1.31-3.25,P=0.002)and teratozoospermia(adjusted OR=1.98,95%CI:1.10-3.55,P=0.02)were observed in Q3 than those in Q1.Our results indicate that a higher risk of abnormal semen parameter values was associated with an increase in time for semen collection,which may be related to male fertility through its association with semen quality.

Effects of mild/asymptomatic COVID-19 on semen parameters and sex-related hormone levels in men:a systematic review and meta-analysis

Coronavirus disease 2019(COVID-19)has yet to be proven to alter male reproductive function,particularly in the majority of mild/asymptomatic patients.The purpose of this study was to explore whether mild/asymptomatic COVID-19 affects semen quality and sex-related hormone levels.To find suitable comparative studies,a systematic review and meta-analysis was done up to January 22,2022,by using multiple databases(Web of Science,PubMed,and Embase).Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines were used to identify and choose the studies.Meta-analysis was used to examine the semen parameters and sex-related hormones of mild/asymptomatic COVID-19 patients before and after infection.The effects of semen collection time,fever,and intensity of verification on semen following infection were also investigated.A total of 13 studies(n=770)were included in the analysis,including three case-control studies,six pre-post studies,and four single-arm studies.A meta-analysis of five pre-post studies showed that after infection with COVID-19,sperm concentration(I^(2)=0;P=0.003),total sperm count(I^(2)=46.3%;P=0.043),progressive motility(I^(2)=50.0%;P<0.001),total sperm motility(I^(2)=76.1%;P=0.047),and normal sperm morphology(I^(2)=0;P=0.001)decreased.Simultaneously,a systematic review of 13 studies found a significant relationship between semen collection time after infection,inflammation severity,and semen parameter values,with fever having only bearing on semen concentration.Furthermore,there was no significant difference in sex-related hormone levels before and after infection in mild/asymptomatic patients.Mild/asymptomatic COVID-19 infection had a significant effect on semen quality in the short term.It is recommended to avoid initiating a pregnancy during this period of time.

Serum vitamin D content is associated with semen|parameters and serum testosterone levels in men

The present study aimed to evaluate the influence of serum vitamin D levels on semen quality and testosterone levels.This is a crosssectional study conducted at Androscience,Science and Innovation Center in Andrology and High-Complex Clinical and Andrology Laboratory in Sao Paulo,Brazil,with 508 male patients,aged 18-60 years,from 2007 to 2017.Seminal parameters and serum sexual hormones were correlated with serum vitamin D concentrations in 260 men selected by strict selection criteria.Patients were divided into normozoospermic group(NZG,n=124)and a group with seminal abnormalities(SAG,n=136).Evaluation included complete physical examination,past medical history,habits and lifestyle factors,two complete seminal analysis with sperm functional tests,serum levels of 25-hydroxy-vitamin D_(3)(25(OH)VD_(3)),total and free testosterone,luteinizing hormone(LH),follicle-stimulating hormone(FSH),sex hormone-binding globulin(SHBG),total cholesterol,homeostatic model assessment of insulin resistance(HOMA-IR)index,and karyotype.The mean concentration of 25(OH)VD_(3)was significantly lower in the SAG(P<0.001)and positively correlated with all baseline seminal parameters and total testosterone levels.In addition,serum vitamin D_(3)concentration was found to be positively correlated with sperm concentration(β=2.103;P<0.001),total number of spermatozoa with progressive motility(β=2.069;P=0.003),total number of motile spermatozoa(β=2.571;P=0.015),and strict morphology(β=0.056;P=0.006),regardless of other variables.This is the first comparative study to address the issue of serum vitamin D_(3)content between normozoospermic patients and those with sperm abnormalities.It clearly demonstrates a direct and positive relationship between serum vitamin D level and overall semen quality,male reproductive potential,and testosterone levels.

Seminal plasma miR-210-3p induces spermatogenic cell apoptosis by activating caspase-3 in patients with varicocele

The aim of this study was to investigate the role of seminal plasma miR-210-3p in the impairment of semen quality caused by varicocele.This study included 102 patients whose semen quality was normal when they were diagnosed with varicocele.A 2-year follow-up for included patients was performed,and they were divided into Group A(semen quality became abnormal)and Group B(semen quality remained normal)according to the results of semen analysis during the follow-up.Semen parameters and seminal plasma miR-210-3p expression were investigated by semen analysis and quantitative real-time polymerase chain reaction,respectively.In vitro experiments with GC-2 cells were performed to explore the role of miR-210-3p in spermatogenic cells.The results of quantitative real-time polymerase chain reaction showed that the level of seminal plasma miR-210-3p in Group A was higher than that in Group B both after 2-year follow-up and when they were diagnosed with varicocele(both P<0.01).Apoptosis and proliferation assays showed that miR-210-3p induces apoptosis of spermatogenic cells by promoting caspase-3 activation.In conclusion,our study indicated that seminal plasma miR-210-3p induces spermatogenic cell apoptosis by activating caspase-3 in patients with varicocele.Seminal plasma miR-210-3p may be a potential biomarker for predicting impaired semen quality caused by varicocele.