Association of urinary and seminal plasma vanadium concentrations with semen quality: A repeated-measures study of 1135 healthy men.

Although animal studies have shown the reproductive toxicity of vanadium, less is known about its effects on semen quality in humans. Among 1135 healthy men who were screened as potential semen donors, we investigated the relationships of semen quality with urinary and seminal plasma vanadium levels via inductively coupled plasma-mass spectrometry (ICP-MS). Spearman rank correlation tests and linear regression models were used to assess the correlations between average urinary and within-individual pooled seminal plasma vanadium concentrations (n = 1135). We utilized linear mixed-effects models to evaluate the associations of urinary and seminal plasma vanadium levels (n = 1135) with repeated sperm quality parameters (n = 5576). Seminal plasma vanadium concentrations were not significantly correlated with urinary vanadium concentrations (r = 0.03). After adjusting for possible confounders, we observed inverse relationships of within-individual pooled seminal plasma vanadium levels with total count, semen volume, and sperm concentration (all P values for trend < 0.05). Specifically, subjects in the highest (vs. lowest) tertile of seminal plasma vanadium concentrations had - 11.3% (-16.4%, -5.9%), - 11.1% (-19.1%, -2.4%), and - 20.9% (-29.0%, -11.8%) lower sperm volume, concentration, and total count, respectively; moreover, urinary vanadium levels appeared to be negatively associated with sperm motility. These relationships showed monotonically decreasing dose-response patterns in the restricted cubic spline analyses. Our results demonstrated a poor correlation between urinary and seminal plasma levels of vanadium, and elevated vanadium concentrations in urine and seminal plasma may be adversely related to male semen quality.

Exogenous Metals Atlas in Spermatozoa at Single-Cell Resolution in Relation to Human Semen Quality.

While exogenous metal/metalloid (metal) exposure has been associated with reduced human semen quality, no study has assessed the associations of exogenous metals in human spermatozoa with semen quality. Here, we developed a strategy to explore the associations between exogenous metals in spermatozoa at single-cell resolution and human semen quality among 84 men screened as sperm donors, who provided 266 semen samples within 90 days. A cellular atlas of exogenous metals at the single-cell level was created with mass cytometry (CyTOF) technology, which concurrently displayed 18 metals in more than 50 000 single sperm. Exogenous metals in spermatozoa at single-cell resolution were extremely heterogeneous and diverse. Further analysis using multivariable linear regression and linear mixed-effects models revealed that the heterogeneity and prevalence of the exogenous metals at single-cell resolution were associated with semen quality. The heterogeneity of lead (Pb), tin (Sn), yttrium (Y), and zirconium (Zr) was negatively associated with sperm concentration and count, while their prevalence showed positive associations. These findings revealed that the heterogeneous properties of exogenous metals in spermatozoa were associated with human semen quality, highlighting the importance of assessing exogenous metals in spermatozoa at single-cell resolution to evaluate male reproductive health risk precisely.

Blood trihalomethane concentrations in relation to sperm mitochondrial DNA copy number and telomere length among 958 healthy men.

BACKGROUND: In animal and human studies, exposure to trihalomethanes (THMs) has been associated with reduced semen quality. However, the underlying mechanisms remain poorly understood. OBJECTIVE: To investigate the associations of blood THM concentrations with sperm mitochondrial DNA copy number (mtDNAcn) and telomere length (TL) among healthy men. METHODS: We recruited 958 men who volunteered as potential sperm donors. A single blood sample was collected from each participant at recruitment and measured for chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM) concentrations. Within a 90-day follow-up, the last semen sample provided by each participant was quantified for sperm mtDNAcn and TL. We used multivariable linear regression models to assess the associations between blood THM concentrations and sperm mtDNAcn and TL. We also performed stratified analyses according to the time intervals between baseline blood THM determinations and semen collection (i.e., 0-9, 10-14, 15-69, or >69 days) to explore potential windows of susceptibility. RESULTS: After adjusting for potential confounders, we found inverse associations between quartiles (or categories) of blood TBM, brominated THM (Br-THM, the sum of BDCM, DBCM, and TBM), and total THM (TTHM, the sum of all four THMs) concentrations and sperm mtDNAcn (all P for trend≤0.03). Besides, we found inverse associations between quartiles of blood TCM, Br-THM, chlorinated THM (Cl-THM, the sum of TCM, BDCM, and DBCM), and TTHM concentrations and sperm TL (all P for trend<0.10). Stratified analyses showed stronger associations between Br-THM concentrations and sperm mtDNAcn determined 15-69 days since baseline exposure determinations, and between blood TCM and TTHM concentrations and sperm TL determined >69 days since baseline exposure determinations. CONCLUSION: Exposure to THMs may be associated with sperm mitochondrial and telomeric dysfunction.

Sperm mitochondrial DNA copy number mediates the association between seminal plasma selenium concentrations and semen quality among healthy men.

Selenium (Se) is essential for successful male reproduction. However, the association of Se status with human semen quality remains controversial and the underlying mechanisms are poorly understood. We measured seminal plasma Se concentrations, sperm mitochondrial DNA copy number (mtDNAcn), and sperm quality parameters among healthy Chinese men screened as potential sperm donors. Linear mixed-effects models were used to investigate the associations of within-subject pooled seminal plasma Se concentrations (n = 1159) with repeated sperm quality parameters (n = 5617); mediation analyses were applied to evaluate the mediating role of sperm mtDNAcn (n = 989). Seminal plasma Se concentrations were positively associated with sperm concentration and total count (both P for trend < 0.001). In adjusted models, men in the top vs. bottom quartiles of seminal plasma Se concentrations had 70.1 % (95 % CI: 53.3 %, 88.9 %) and 59.1 % (95 % CI: 40.5 %, 80.2 %) higher sperm concentration and total count, respectively. Meanwhile, we observed inverse associations between seminal plasma Se concentrations and sperm mtDNAcn, and between sperm mtDNAcn and sperm motility, concentration, and total count (all P for trend < 0.05). Mediation analyses suggested that sperm mtDNAcn mediated 19.7 % (95 % CI: 15.9 %, 25.3 %) and 23.1 % (95 % CI: 17.4 %, 33.4 %) of the associations between seminal plasma Se concentrations and sperm concentration and total count, respectively. Our findings suggest that Se is essential for male spermatogenesis, potentially by affecting sperm mtDNAcn.

Physical activity and sedentary time in relation to semen quality in healthy men screened as potential sperm donors.

STUDY QUESTION: Is physical activity or sedentary time associated with semen quality parameters? SUMMARY ANSWER: Among healthy men screened as potential sperm donors, higher self-reported physical activity was associated with increased progressive and total sperm motility. WHAT IS KNOWN ALREADY: Despite the claimed beneficial effect of moderate physical activity on semen quality, results from epidemiological studies have been inconclusive. Previous studies were mostly conducted among endurance athletes or male partners of couples who sought infertility treatment. STUDY DESIGN, SIZE, DURATION: Healthy men screened as potential sperm donors were recruited at the Hubei Province Human Sperm Bank of China. Between April 2017 and July 2018; 746 men completed the long-form International Physical Activity Questionnaire (IPAQ) and provided repeated semen samples (n = 5252) during an approximately 6-month period. PARTICIPANTS/MATERIALS, SETTING, METHODS: Total metabolic equivalents (METs), moderate-to-vigorous METs and sedentary time were abstracted from the IPAQ. Sperm concentration, total sperm count, progressive motility and total motility in repeated specimens were determined by trained clinical technicians. Mixed-effect models were applied to investigate the relationships between physical activity and sedentary time and repeated measures of semen quality parameters. MAIN RESULTS AND THE ROLE OF CHANCE: After adjusting for multiple confounders, total METs and moderate-to-vigorous METs were both positively associated with progressive and total sperm motility. Compared with men in the lowest quartiles, those in the highest quartiles of total and moderate-to-vigorous METs had increased progressive motility of 16.1% (95% CI: 6.4, 26.8%) and 17.3% (95% CI: 7.5, 27.9%), respectively, and had increased total motility of 15.2% (95% CI: 6.2, 24.9%) and 16.4% (95% CI: 7.4, 26.1%), respectively. Sedentary time was not associated with semen quality parameters. LIMITATIONS, REASONS FOR CAUTION: The IPAQ was reported only once from study participants; measurement errors were inevitable and may have biased our results. Furthermore, although we have adjusted for various potential confounders, the possibility of unmeasured confounding cannot be fully ruled out. WIDER IMPLICATIONS OF THE FINDINGS: Our findings suggest that maintaining regular exercise may improve semen quality parameters among healthy, non-infertile men. Specifically, we found that higher self-reported total and moderate-to-vigorous METs were associated with improved sperm motility, which reinforces the existing evidence that physical activity may improve male reproductive health. STUDY FUNDING/COMPETING INTEREST(S): Y.-X.W was supported by the Initiative Postdocs Supporting Program (No. BX201700087). A.P. was supported by the National Key Research and Development Program of China (2017YFC0907504). C.-L.X. was supported by the National Key Research and Development Program of China (2016YFC1000206). The authors report no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Profiles, variability and predictors of concentrations of blood trihalomethanes and urinary haloacetic acids along pregnancy among 1760 Chinese women.

Blood trihalomethanes (THMs) and urinary haloacetic acids (HAAs) are the leading candidate biomarkers for disinfection byproduct (DBP) exposure. However, no studies have assessed the exposure profiles, temporal variability, and potential predictors of these biomarkers during pregnancy. Here we collected blood (n = 4304) and urine samples (n = 4165) from 1760 Chinese pregnant women during early, mid-, and late pregnancy, which were separately analyzed for 4 THMs and 2 HAAs. We calculated the intraclass correlation coefficients (ICCs) to assess the variability of these biomarkers and estimated their correlations with sociodemographic, water-use behavioral, dietary and sample collection factors using mixed models. The median concentrations of TCM, BDCM, Br-THMs [sum of BDCM, dibromochloromethane (DBCM), bromoform (TBM)], total THMs (TTHMs, sum of TCM and Br-THMs), DCAA and TCAA in the water distribution system were 4.2 µg/L, 1.7 µg/L, 2.9 µg/L, 7.1 µg/L, 3.4 µg/L and 8.2 µg/L, respectively. Chloroform (TCM), bromodichloromethane (BDCM), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were detected in > 75% of the biospecimens. Repeated measurements of blood TCM, BDCM, Br-THMs and TTHMs and urinary DCAA and TCAA uniformly exhibited high variability (ICCs = 0.01-0.13); the use of a single measurement to classify gestational average exposure resulted in a high degree of exposure misclassification. The sampling season was a strong predictor of all analyzed DBPs. Additionally, we detected a positive association of blood TCM and BDCM with household income, urinary DCAA with age, and urinary TCAA with tap water usage, education level and amount of tap water consumed. Inverse associations were found between blood BDCM and vegetable consumption, and between blood Br-THM and TTHM and time interval since the last bathing/showering. Afternoon samples had lower DCAA concentrations than did early morning samples. Our results indicate that blood THM and urinary HAA concentrations vary greatly over the course of pregnancy and are affected by sampling season, time of day of blood/urine collection, sociodemographic factors, recent water-use activities and dietary intake.

[Serum anti-Müllerian hormone level for differential diagnosis of obstructive and non-obstructive azoospermia].

OBJECTIVE: To determine whether the serum anti-Müllerian hormone (AMH) level can be used as a serum marker for the differential diagnosis of obstructive azoospermia (OA) and non-obstructive azoospermia (NOA). METHODS: Using chemiluminescence immunoassay, we detected the levels of serum AMH, inhibin B (IhB) and follicle stimulating hormone (FSH) and measured by scrotal ultrasound the testis volume of 43 normal fertile men and 14 OA and 45 NOA male patients, followed by a comparative analysis of the data obtained among the three groups subjects. RESULTS: Compared with the NOA patients, the men in the normal control and OA groups showed significantly higher levels of AMH (ï¼»5.65 ± 3.13ï¼½ vs ï¼»8.13 ± 3.95ï¼½ and ï¼»8.51 ± 4.77ï¼½ ng/ml, P < 0.05) and InH (ï¼»25.98±16.29ï¼½ vs ï¼»127.38 ± 40.5ï¼½ and ï¼»131.25 ± 52.3ï¼½ pg/ml, P < 0.01), but a lower level of FSH (ï¼»19.87 ± 13.09ï¼½ vs ï¼»4.22 ± 3.23ï¼½ and ï¼»4.54 ± 2.09ï¼½ IU/L, P < 0.01), none with statistically significant difference between the latter two groups (P > 0.05). Pearson correlation analysis exhibited that the level of IhB was correlated positively with that of AMH (r = 0.326, P = 0.01) but negatively with that of FSH (r =－0.662, P < 0.01), the FSH level negatively with the AMH level (r = －0.468, P < 0.01), the testis volume positively with the levels of AMH (r = 0.339, P < 0.01) and IhB (r = 0.733, P < 0.01) but negatively with that of FSH (r = 0.597, P < 0.01), the sperm concentration positively with that of IhB (r = 0.522, P < 0.01) but negatively with that of FSH (r = －0.421, P < 0.01), and the testis volume positively with the sperm concentration (r = 0.605, P < 0.01). CONCLUSIONS: AMH can be used as one of the serum markers for testicular spermatogenesis and employed alone or in combination with IhB and FSH for the differential diagnosis of OA and NOA.

Analysis of the Screening Results for 3,564 Student Sperm Donors in Hubei Province, China.

OBJECTIVE: To determine the reasons for the elimination of student sperm donors after semen analysis, physical examination, and laboratory tests in the Hubei Provincial Human Sperm Bank. Understanding the status of student sperm donors can provide a valid reference for the screening work of sperm banks. STUDY DESIGN: The screening data from 3,564 student sperm donors in Hubei Provincial Human Sperm Bank from January 1, 2010-April 30, 2013, were retrospectively analyzed. RESULTS: A total of 733 students (20.57%) qualified for semen analysis in the human sperm bank, whereas 602 students (16.89%) completed the sperm donation procedure. The main reasons for elimination were as follows: unqualified semen parameters (2,748 cases), failed semen extraction (83 cases), sexually transmitted diseases (44 cases), hereditary or chromosomal disorders (44 cases), and hepatitis B infection (25 cases). Education level and temperature/climate possibly affect semen quality. CONCLUSION: Unqualified semen parameters were the main reason for elimination among student sperm donors. Human sperm banks should promote reproductive health knowledge and information on improving semen quality among students when promoting sperm donation.

n-Butanol extract of Rhynchosia volubilis Lour: a potent spermicidal agent In Vitro.

Rhynchosia volubilis Lour has been a major drug in a folk prescription for contraception in China, whereas its mechanism remains unknown. Its antifertility effects on male mice and antimicrobial activities on sexually transmitted infection (STI) pathogens were previously reported. This study was undertaken to develop the n-Butanol extract of Rhynchosia volubilis Lour (BERVL) as a spermicidal agent with STI prevention. The spermicidal activities of BERVL with different doses were assessed using selected high-motile sperms of normal human semen samples, and their inhibitory effects on Lactobacillus acidophilus were determined. The mechanism of the spermicidal activity was explored by aqueous Eosin Y and Hoechst 33342/PI staining. The results showed spermicidal activities and inhibitory effects of BERVL on Lactobacillus acidophilus were dose-dependent. Dose of 90 mg/mL BERVL terminated all progressive sperm motility within 2 min, and had slight inhibitory effect on Lactobacillus acidophilus, suggesting it was an effective and safe dose for contraception use. About 80% sperms exposed to BERVL displayed changes consistent with high permeability of head membrane. It is concluded that BERVL as spermicide has advantages over N-9 with strong ability to instantaneously kill human sperm and possesses light inhibitory effect on Lactobacillus acidophilus.

[Screening results and causes of uncompleted donation process in 1 145 sperm donors].

OBJECTIVE: To improve the reception and recruitment of sperm donors in sperm banks in China, and solve the problem of insufficiency in sperm donation. METHODS: We reviewed the recruitment of 1 145 men for sperm donation in the Human Sperm Bank of Hubei Province from September 2011 to April 2012, analyzed the reasons for those not included, and interviewed those included but unwilling to donate sperm. RESULTS: Among the 1 145 recruits, 551 (48.12%) were students and 594 (51.88%) were other individuals. After the first semen screening, 503 (43.93%) quitted, including 202 students (36.66% of the students recruited) and 301 others (50.67% of the other individuals recruited). After the second semen screening, 432 (37.73%) were excluded, and another 45 (3.93%) excluded after laboratory examination, including 16 cases of mycoplasma positive. Totally, 165 recruits (14.41%) passed the semen screening and laboratory examination, but only 144 of them (87.27%) completed, while the other 21 (12.73%) failed to complete the whole donation process. CONCLUSION: Low rates of screening qualification and donation process completion are common problems in human sperm banks. The rate of qualified sperm donors can be increased and the operational cost of the human sperm bank can be reduced by enabling the recruits to accomplish the whole donation process. Explanation at the reception, later interview with the recruits, and donors' trust in the sperm bank play important roles in raising the completion rate of sperm donation process.

Phthalate exposure with sperm quality among healthy Chinese male adults: The role of sperm cellular function.

Adverse male reproduction caused by phthalate ester (PAE) exposure has been well documented in vivo. However, existing evidence from population studies remains inadequate to demonstrate the impact of PAE exposure on spermatogenesis and underlying mechanisms. Our present study aimed to explore the potential link between PAE exposure and sperm quality and the possible mediation by sperm mitochondrial and telomere in healthy male adults recruited from the Hubei Province Human Sperm Bank, China. Nine PAEs were determined in one pooled urine sample prepared from multiple collections during the spermatogenesis period from the same participant. Sperm telomere length (TL) and mitochondrial DNA copy number (mtDNAcn) were determined in sperm samples. The sperm concentration and count per quartile increment in mixture concentrations were -4.10 million/mL (-7.12, -1.08) and -13.52% (-21.62%, -4.59%), respectively. We found one quartile increase in PAE mixture concentrations to be marginally associated with sperm mtDNAcn (ß = 0.09, 95% CI: -0.01, 0.19). Mediation analysis showed that sperm mtDNAcn significantly explained 24.6% and 32.5% of the relationships of mono-2-ethylhexyl phthalate (MEHP) with sperm concentration and sperm count (ß = -0.44 million/mL, 95% CI: -0.82, -0.08; ß = -1.35, 95% CI: -2.54, -0.26, respectively). Our study provided a novel insight into the mixed effect of PAEs on adverse semen quality and the potential mediation role of sperm mtDNAcn.

Association of handgrip strength with semen characteristics: a study with repeated measurements among healthy Chinese men.

Accumulating epidemiological evidence shows that handgrip strength provides predictive potential in physical, mental, and reproductive health status. However, the associations between handgrip strength and semen characteristics have not been explored. We recruited 1382 eligible men at the Hubei Province Human Sperm Bank (Wuhan, China) who had their handgrip strength measured at recruitment and provided 6458 repeated semen specimens within a 6-month period. Semen characteristics, including semen volume, sperm motility parameters (immotility, nonprogressive motility, and progressive motility), and sperm concentration, were assessed. Mixed-effect models and restricted cubic spline functions were applied to investigate the relationship of handgrip strength with repeated measurements of semen characteristics. After adjusting for confounding factors, the mixed-effect models revealed that handgrip strength was positively associated with semen volume, sperm concentration, progressive motility, total motility, and total count (all P for trend < 0.05). Compared to men in the lowest quartile, those in the highest quartile of handgrip strength had higher semen volume, sperm concentration, progressive motility, total motility, and total count, with measurements of 14.2% (95% confidence interval [CI]: 5.9%-23.2%), 19.5% (95% CI: 7.3%‒33.1%), 9.5% (95% CI: 3.4%‒15.9%), 8.8% (95% CI: 3.2%‒14.6%), and 36.4% (95% CI: 18.9%‒56.5%), respectively. These positive dose-response relationships were further confirmed in restricted cubic splines, where handgrip strength was modeled as a continuous variable. Handgrip strength, as an indicator of muscular function and strength, was positively associated with semen characteristics in a dose-dependent manner.

Exposure profiles and predictors of a cocktail of environmental chemicals in Chinese men of reproductive age.

Personal care products, such as additives, have raised widespread concerns about the potential threat to male reproductive health. The spermatogenesis in humans lasts for approximately 90 days, the average levels of these chemicals remain unclear during spermatogenesis. In our study, we pooled urine samples from each man during the days of 1-15, 16-31, 32-63, and ≥64, and examined exposure to 48 typical additive chemicals. By principal component analysis (PCA), k-means clustering, and Spearman's rank correlations, we then identified 6 PC scores and 4 clusters based on profiles of these chemicals. Some industrial, commercial or structural similar chemicals (e.g., phthalates) were significantly correlated compared to unrelated chemicals (e.g., benzophenone). PCA scores were associated with individual lifestyles (e.g., household income, tea consumption, and drinking tap water). Distinct exposure components and exposure patterns of personal care products may help the reproductive health assessment of men. We suggested more concerns for widespread exposure to these chemicals for men.

Associations between depression, oxidative stress, and semen quality among 1,000 healthy men screened as potential sperm donors.

OBJECTIVE: To explore the association between depression and semen quality and the mediating role of oxidative stress. DESIGN: Cross-sectional study with repeated measures of semen quality. SETTING: Human Sperm Bank of Hubei Province, People's Republic of China. PATIENT(S): From April 2017 to July 2018, we recruited 1,000 potential sperm donors who completed the Beck Depression Inventory questionnaire and had measures of oxidative stress biomarkers. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Severity of depression was evaluated by the Beck Depression Inventory scores (0-4, no depression; 5-13, mild depression; 14-20, moderate depression; and 21 or greater, severe depression). The urinary concentrations of 8-hydroxy-2-deoxyguanosine, 4-hydroxy-2-nonenal-mercapturic acid, and 8-iso-prostaglandin F2α (8-isoPGF2α) were measured to reflect oxidative stress status. Repeated semen quality parameters (n = 5,880) were examined by trained professional technicians according to the World Health Organization laboratory manual. Associations between depression, oxidative stress, and repeated measures of semen quality parameters were evaluated using linear or mixed-effects models with adjustment for potential confounders. Mediation analysis was performed to test the potential mediating role of oxidative stress. RESULT(S): A total of 391 (39.1%) men were classified as mild depression, 67 (6.7%) as moderate depression, and 19 (1.9%) as severe depression. Inverse dose-response relationships between severity of depression and semen quality parameters were found. Compared with men without depression (n = 523), those with severe depression had a 25.26% (95% confidence interval, -38.65%, -8.93%) lower semen volume, 37.04% (-55.37%, -11.20%) lower total sperm count, 13.57% (-23.17%, -2.78%) lower total motility, and 15.08% (-25.09%, -3.72%) lower progressive motility; men with moderate depression also had a 12.28% (-21.16%, -2.40%) lower semen volume and 23.56% (-36.50%, -7.97%) lower total sperm count. We found a positive dose-response relationship between severity of depression and urinary 8-isoPGF2α concentrations. However, we found no evidence that the associations between depression status and semen quality were mediated by oxidative stress markers. CONCLUSION(S): In the study of Chinese male sperm donors, men with depression had worse semen quality parameters, including semen volume, sperm concentration, total sperm count, total motility, and progressive motility. Although depression was positively associated with urinary 8-isoPGF2α concentrations, depression-semen quality associations were not mediated by oxidative stress.

Association between electronic device usage and sperm quality parameters in healthy men screened as potential sperm donors.

Cell phone use and radio-frequency electromagnetic radiation (RF-EMF) are rapidly increasing and may be associated with lower semen quality, yet results from epidemiological studies are inconclusive. Information on electronic devices use was collected through standard questionnaires from 1454 men aged 22-45 years old. Semen volume, sperm concentration, total sperm count, total motility, progressive motility, and normal morphology in repeated specimens were determined by trained clinical technicians. Percent changes [95% confidence intervals (CIs)] were estimated as (10ß-1) × 100 for electronic devices use associated with repeated sperm quality parameters in the linear mixed-effect models. After adjusting for multiple confounders, we found significant inverse associations of total duration of electronic devices use with sperm progressive motility and total motility, duration of cell phone and computer use with sperm concentration, progressive motility, and total motility (all P < 0.05). No significant association was found between cell phone/computer use alone and sperm quality parameters. Moreover, per hour increase of time spent on cell phone talking was associated with decreased sperm concentration and total count by an average of -8.0% (95% CI: -15.2%, -0.2%) and -12.7% (95% CI: -21.3%, -3.1%), respectively. Besides, daily calling time was associated with lower sperm progressive motility and total motility among those who used headsets during a call (P for interaction <0.05). In conclusion, our study suggested that more time spent on electronic devices use had a modest reduction effect on semen quality. Daily calling time was significantly associated with lower sperm concentration and total count, and using headsets during a call appeared to aggravate the negative association between daily calling time and sperm motility. Additional studies are needed to confirm these findings.

Transcriptome and DNA methylome analysis of peripheral blood samples reveals incomplete restoration and transposable element activation after 3-months recovery of COVID-19.

Comprehensive analyses showed that SARS-CoV-2 infection caused COVID-19 and induced strong immune responses and sometimes severe illnesses. However, cellular features of recovered patients and long-term health consequences remain largely unexplored. In this study, we collected peripheral blood samples from nine recovered COVID-19 patients (median age of 36 years old) from Hubei province, China, 3 months after discharge as well as 5 age- and gender-matched healthy controls; and carried out RNA-seq and whole-genome bisulfite sequencing to identify hallmarks of recovered COVID-19 patients. Our analyses showed significant changes both in transcript abundance and DNA methylation of genes and transposable elements (TEs) in recovered COVID-19 patients. We identified 425 upregulated genes, 214 downregulated genes, and 18,516 differentially methylated regions (DMRs) in total. Aberrantly expressed genes and DMRs were found to be associated with immune responses and other related biological processes, implicating prolonged overreaction of the immune system in response to SARS-CoV-2 infection. Notably, a significant amount of TEs was aberrantly activated and their activation was positively correlated with COVID-19 severity. Moreover, differentially methylated TEs may regulate adjacent gene expression as regulatory elements. Those identified transcriptomic and epigenomic signatures define and drive the features of recovered COVID-19 patients, helping determine the risks of long COVID-19, and guiding clinical intervention.

Gut Microbiota May Not Be Fully Restored in Recovered COVID-19 Patients After 3-Month Recovery.

Coronavirus disease 2019 (COVID-19) has infected over 124 million people worldwide. In addition to the development of therapeutics and vaccines, the evaluation of the sequelae in recovered patients is also important. Recent studies have indicated that COVID-19 has the ability to infect intestinal tissues and to trigger alterations of the gut microbiota. However, whether these changes in gut microbiota persist into the recovery stage remains largely unknown. Here, we recruited seven healthy Chinese men and seven recovered COVID-19 male patients with an average of 3-months after discharge and analyzed their fecal samples by 16S rRNA sequencing analysis to identify the differences in gut microbiota. Our results suggested that the gut microbiota differed in male recovered patients compared with healthy controls, in which a significant difference in Chao index, Simpson index, and ß-diversity was observed. And the relative abundance of several bacterial species differed clearly between two groups, characterized by enrichment of opportunistic pathogens and insufficiency of some anti-inflammatory bacteria in producing short chain fatty acids. The above findings provide preliminary clues supporting that the imbalanced gut microbiota may not be fully restored in recovered patients, highlighting the importance of continuous monitoring of gut health in people who have recovered from COVID-19.

Identifying windows of susceptibility to essential elements for semen quality among 1428 healthy men screened as potential sperm donors.

BACKGROUND: Essential elements such as iron (Fe), cobalt (Co), copper (Cu), zinc (Zn), selenium (Se), rubidium (Rb), strontium (Sr), and molybdenum (Mo) are necessary for reproductive health. However, their associations with human semen quality remain inconclusive. OBJECTIVES: To investigate the associations of urinary Fe, Co, Cu, Zn, Se, Rb, Sr, and Mo concentrations with semen quality in healthy men screened as potential sperm donors and identify critical windows of susceptibility. METHODS: 1428 healthy men provided 3766 urine and 6527 semen samples, which were measured for urinary essential element concentrations and sperm quality parameters, respectively. Linear mixed models and cubic spline curves were used to evaluate associations between urinary essential elements and semen quality. Multiple informant models were used to identify potential critical windows of susceptibility. RESULTS: Linear mixed models and cubic spline curves showed positive dose-response relationships between urinary Zn and sperm concentration and total count and between urinary Mo and total sperm count [all False Discovery Rate (FDR) adjusted p-value for trend < 0.05]. In the multiple-element linear mixed models, the men in the highest versus lowest quartiles of urinary Zn and Mo had a higher sperm concentration of 17.5% (95% CI: 2.8%, 34.2%; p-value for trend = 0.006) and total sperm count of 18.3% (95% CI: 1.4%, 38.0%; p-value for trend = 0.027), respectively. Urinary Zn was also positively associated with total sperm count in a dose-dependent manner (p-value for trend = 0.036), though the percentile difference in total sperm count between men in the highest and lowest quartile was not statistically significant (16.4%, 95% CI: -1.7%, 37.9%). These associations appeared to be stronger when urinary Zn and Mo were measured at 0-9 days before the date of semen examination (i.e., corresponding to epididymal storage). CONCLUSIONS: Higher urinary Zn and Mo, particularly during the period of epididymal storage, were associated with greater sperm production.

Sleep duration and quality in relation to semen quality in healthy men screened as potential sperm donors.

BACKGROUND: Short sleep duration and poor sleep quality are increasingly prevalent in modern society and may be associated with impaired semen quality, yet studies are inconclusive. OBJECTIVES: To investigate the reproducibility of semen quality parameters among 842 healthy men screened as potential sperm donors and explore the associations of sleep duration and quality with repeated measures of semen quality parameters. METHODS: We assessed sleep duration (night sleep and daytime napping) and sleep quality using the Pittsburgh Sleep Quality Index (PSQI) among 842 healthy men screen as potential sperm donors. We examined sleep characteristics in relation to repeated measurements (n = 5601) of semen parameters using linear mixed-effects models. RESULTS: High degrees of within-individual variability were found for total and progressive sperm motility with intraclass correlation coefficient (ICC) of 0.20 and 0.22, respectively; while fair-to-good reproducibilities were observed for sperm volume, concentration, and total count (ICC = 0.54, 0.62, and 0.50, respectively). Compared to men with total sleep duration of 8.0-8.5 h/day (h/d), men who slept less than 6.0 h/d and higher than 9.0 h/d had lower sperm volume of 12% [95% confidence interval (CI): -22%, -0.68%] and 3.9% (95% CI: -7.3%, -0.44%), respectively. Compared to men with night sleep duration of 7.5-8.0 h/d, men who slept less than 6.0 h/d had lower total and progressive sperm motility of 4.4% (95 CI:-8.4%, -0.24%) and 5.0% (95% CI: -9.2%, -0.48%), respectively. Compared to men who reported good sleep quality (total PSQI score ≤5.0), those reporting poor sleep quality (total PSQI score >5.0) had lower total sperm count, total motility, and progressive motility of 8.0% (95% CI: -15%, -0.046%), 3.9% (95% CI: -6.2%, -1.5%), and 4.0% (95% CI: -6.5%, -1.4%), respectively. CONCLUSIONS: Both long and short sleep duration and poor sleep quality were associated with impaired semen quality parameters. The high within-individual variability of total and progressive sperm motility suggests that a single measurement may result in a moderate degree of classification error.

Associations of blood trihalomethanes with semen quality among 1199 healthy Chinese men screened as potential sperm donors.

BACKGROUND: Trihalomethanes (THMs) have demonstrated adverse effects on male reproductive systems in experimental animals, but human evidence has been inconsistent. Prior researches have been limited by small sample sizes and inadequate exposure assessment. OBJECTIVES: To investigate the association between blood THMs and repeated measurements of semen quality parameters among 1199 healthy men screened as potential sperm donors. METHODS: We recruited healthy men presenting to the Hubei Province Human Sperm Bank from April to December 2017. At study entry, each participant provided a spot blood sample which was used to quantify blood concentrations of four THMs: chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM) and bromoform (TBM). The summary measures of exposure for brominated THMs (Br-THMs; molar sum of BDCM, DBCM and TBM) and total THMs (TTHMs; molar sum of TCM and Br-THMs) were also calculated. We used multivariable linear regression models to estimate the cross-sectional associations of tertiles of blood THM concentrations with semen quality parameters measured at study entry, and mixed-effect models to estimate the longitudinal associations accounting for repeated measures of semen quality, adjusting for relevant confounding factors. RESULTS: In the cross-sectional analysis, several inverse dose-response relationships were observed across tertiles of blood TCM concentrations and sperm count, total motility and progressive motility, and between blood DBCM, and Br-THMs, and TTHMs and sperm count and concentration. The inverse associations of blood TCM, DBCM, Br-THMs and TTHMs with sperm count were confirmed in the longitudinal, repeated measure analysis. CONCLUSION: Our results suggest that exposure to THMs from drinking water may be related to decreased semen quality in young healthy men.