Type of underwear worn and markers of testicular function among men attending a fertility center

AZIN2 is associated with apoptosis of germ cells in undescended testis

Undescended testis (UDT), known as cryptorchidism (CRY), is a common congenital disorder in which one or both testicles do not descend normally into the scrotum. A unilateral UDT model was established by inducing UDT in mice through surgery. The results showed that the testis in the UDT model group was abnormal; the lumen of the seminiferous tubule was atrophic; apoptosis, necrosis and shedding were observed in many of the germ cells; the level of sex hormones was abnormal; and mature sperm was reduced. Subsequently, transcriptome sequencing was conducted on the testicular tissue of UDT model mice. Through analysis and verification of differential genes, AZIN2 was identified as playing a key role in the decline in male fertility caused by cryptorchidism. AZIN2 expression and spermine content was down-regulated in the testis of the UDT group. We then used a combination of hypoxanthine and xanthine to create a GC-1 cell damage model. In this model, AZIN2 expression and spermine content was down-regulated. When si-Azin2 transfected GC-1 cells, cell viability and proliferation were decreased. However, in the GC-1 cell damage model transfected with Azin2 over-expressed plasmid, AZIN2 expression and spermine content was up-regulated, reversing the cell damage caused by hypoxanthine and xanthine, and restoring the proliferation ability of GC-1 cells. These results indicate that in UDT, down-regulated AZIN2 expression is a factor in testicular damage. This discussion of the connection between AZIN2 and germ cells has important clinical significance as it provides an important reference for the diagnosis and treatment of cryptorchidism.

The Role of Heat-Induced Stress Granules in the Blood-Testis Barrier of Mice

Stress granules (SGs) are membraneless ribonucleoprotein (RNP)-based cellular foci formed in response to stress, facilitating cell survival by protecting against damage. Mammalian spermatogenesis should be maintained below body temperature for proper development, indicating its vulnerability to heat stress (HS). In this study, biotin tracer permeability assays showed that the inhibition of heat-induced SG assembly in the testis by 4-8 mg/kg cycloheximide significantly increased the percentage of seminiferous tubules with a damaged blood-testis barrier (BTB). Western blot results additionally revealed that the suppression of heat-induced SG assembly in Sertoli cell line, TM4 cells, by RNA inference of G3bp1/2 aggravated the decline in the BTB-related proteins ZO-1, β-Catenin and Claudin-11, indicating that SGs could protect the BTB against damage caused by HS. The protein components that associate with SGs in Sertoli cells were isolated by sequential centrifugation and immunoprecipitation, and were identified by liquid chromatography with tandem mass spectrometry. Gene Ontology and KEGG pathway enrichment analysis revealed that their corresponding genes were mainly involved in pathways related to proteasomes, nucleotide excision repair, mismatch repair, and DNA replication. Furthermore, a new SG component, the ubiquitin associated protein 2 (UBAP2), was found to translocate to SGs upon HS in TM4 cells by immunofluorescence. Moreover, SG assembly was significantly diminished after UBAP2 knockdown by RNA inference during HS, suggesting the important role of UBAP2 in SG assembly. In addition, UBAP2 knockdown reduced the expression of ZO-1, β-Catenin and Claudin-11, which implied its potential role in the function of the BTB. Overall, our study demonstrated the role of SGs in maintaining BTB functions during HS and identified a new component implicated in SG formation in Sertoli cells. These findings not only offer novel insights into the biological functions of SGs and the molecular mechanism of low fertility in males in summer, but also potentially provide an experimental basis for male fertility therapies.

Results of lifestyle modification promotion and reproductive/general health check for male partners of couples seeking conception

Purpose

Male infertility is partially caused by an inappropriate lifestyle and comorbidities. In this study, we analyzed the prevalence of these factors and the effects of lifestyle modifications as part of male preconception care.

Methods

Four hundred and two male partners of couples seeking conception with abnormal parameters upon the first semen analysis were enrolled. They were advised to modify their inappropriate lifestyle as male preconception care. Afterward, their general and male reproductive health was examined. Semen quality was compared before and after the promotion.

Results

Smoking, chronic alcohol use, and genital heat stress were found in 22.6%, 47.0%, and 75.1% of patients, respectively. Palpable varicoceles, hypogonadism, obesity (body mass index ≧30 kg/m²), hypertension, zinc deficiency, hyperlipidemia, liver dysfunction, and diabetes mellitus were found in 25.9%, 17.0%, 7.0%, 14.9%, 16.2%, 37.0%, 26.9% and 3.4% of the participants, respectively; 98.8% of the patients had at least one factor. After the promotion, semen parameters and sperm DNA fragmentation were improved significantly. Improvement was found in those with palpable varicocele or hypogonadism but not in those with night work shift, abstinence (>3 days), erectile dysfunction, hypertension, obesity, zinc deficiency, or diabetes mellitus.

Conclusions

Comorbidities and inappropriate lifestyle choices were common among men with infertility. The promotion of lifestyle modifications as part of male preconception care could improve semen quality without urologic intervention.

Male personal heat exposures and fecundability: A preconception cohort study

BACKGROUND

Several studies indicate adverse effects of selected heat exposures on semen quality, but few studies have directly evaluated fertility as an endpoint.

OBJECTIVE

We evaluated prospectively the association between male heat exposures and fecundability, the per-cycle probability of conception.

MATERIALS AND METHODS

We analyzed data from 3041 couples residing in the United States or Canada who enrolled in a prospective preconception cohort study (2013-2021). At enrollment, males reported on several heat-related exposures, such as use of saunas, hot baths, seat heaters, and tight-fitting underwear. Pregnancy status was updated on female follow-up questionnaires every 8 weeks until conception or a censoring event (initiation of fertility treatment, cessation of pregnancy attempts, withdrawal, loss to follow-up, or 12 cycles), whichever came first. We used proportional probabilities regression models to estimate fecundability ratios (FR) and 95% confidence intervals (CIs) for the association between heat exposures and fecundability, mutually adjusting for heat exposures and other potential confounders.

RESULTS

We observed small inverse associations for hot bath/tub use (≥3 vs. 0 times/month: FR = 0.87, 95% CI: 0.70-1.07) and fever in the 3 months before baseline (FR = 0.94, 95% CI: 0.79-1.12; one cycle of follow-up: FR = 0.84, 95% CI: 0.64-1.11). Little association was found for sauna use, hours of laptop use on one's lap, seat heater use, time spent sitting, and use of tight-fitting underwear. Based on a cumulative heat metric, FRs for 1, 2, 3, and ≥4 versus 0 heat exposures were 0.99 (95% CI: 0.87-1.12), 1.03 (95% CI: 0.89-1.19), 0.94 (95% CI: 0.74-1.19), and 0.77 (95% CI: 0.50-1.17), respectively. Associations were stronger among men aged ≥30 years (≥4 vs. 0 heat exposures: FR = 0.60, 95% CI: 0.34-1.04).

CONCLUSION

Male use of hot tubs/baths and fever showed weak inverse associations with fecundability. Cumulative exposure to multiple heat sources was associated with a moderate reduction in fecundability, particularly among males aged ≥30 years.

[Impact of lifestyle and environmental factors on male reproductive health]

The identification of potential environmental hazards is of clinical relevance for the diagnosis of male infertility. Knowledge about these factors will improve prevention of fertility disorders. Apart from drugs or factors related to lifestyle such as alcohol and tobacco smoke, various environmental and occupational agents, both chemical and physical, may impair male reproduction. Reproductive toxicity may evolve at the hypothalamic-pituitary, testicular, or posttesticular level; endpoints comprise deterioration of spermatogenesis and sperm function as well as endocrine disorders and sexual dysfunction. However, due to the complex regulation of the male reproductive system, information regarding single exogenous factors and their mechanisms of action in humans is limited. This is also due to the fact that extrapolation of results obtained from experimental animal or in vitro studies remains difficult. Nevertheless, the assessment of relevant exposures to reproductive toxicants should be carefully evaluated during diagnostic procedures of andrological patients.

The effects and molecular mechanism of heat stress on spermatogenesis and the mitigation measures

Under normal conditions, to achieve optimal spermatogenesis, the temperature of the testes should be 2-6 °C lower than body temperature. Cryptorchidism is one of the common pathogenic factors of male infertility. The increase of testicular temperature in male cryptorchidism patients leads to the disorder of body regulation and balance, induces the oxidative stress response of germ cells, destroys the integrity of sperm DNA, yields morphologically abnormal sperm, and leads to excessive apoptosis of germ cells. These physiological changes in the body can reduce sperm fertility and lead to male infertility. This paper describes the factors causing testicular heat stress, including lifestyle and behavioral factors, occupational and environmental factors (external factors), and clinical factors caused by pathological conditions (internal factors). Studies have shown that wearing tight pants or an inappropriate posture when sitting for a long time in daily life, and an increase in ambient temperature caused by different seasons or in different areas, can cause an increase in testicular temperature, induces testicular oxidative stress response, and reduce male fertility. The occurrence of cryptorchidism causes pathological changes within the testis and sperm, such as increased germ cell apoptosis, DNA damage in sperm cells, changes in gene expression, increase in chromosome aneuploidy, and changes in Na⁺/K⁺-ATPase activity, etc. At the end of the article, we list some substances that can relieve oxidative stress in tissues, such as trigonelline, melatonin, R. apetalus, and angelica powder. These substances can protect testicular tissue and relieve the damage caused by excessive oxidative stress.

The Impact of High Ambient Temperature on Human Sperm Parameters: A Meta-Analysis

Background

Global warming, lifestyle, or working in a high temperature environment leads to have increased health risk factors. This meta-analysis was conducted to determine the impact of high ambient temperature on male reproductive function.

Methods

Scientific articles were screened in the database including MEDLINE, EMBASE, National center for biotechnology information (NCBI) or Web of Science with relating keywords. Impact data of high ambient temperature on semen parameters were extracted and analyzed by STATA software according to the Random Effects Model. The high ambient temperature exposure group and Non-exposure group were compared using the standard mean difference (SMD). Publications were evaluated for publication bias by Egger test.

Results

Nine articles were finally selected from databases examining the effect of high ambient temperature on male reproductive health of 356 men from Iran, Italy, Thailand, China, Egypt. High ambient temperature showed a significant decrease in the seminal parameters, semen volume during each ejaculation (SMD = -0.74; 95% CI -1.11, -0.36), sperm concentration (SMD = -1.07; 95% CI -1.42, -0.72), total sperm count (SMD = -1.52; 95% CI -2.96, -0.08), sperm motility (SMD = -1.93; 95% CI -2.83, -1.04), sperm progressive motility (SMD = -1.65; 95% CI -2.39, -0.91) and normal morphology (SMD = -2.41; 95% CI -3.30, -1.52).

Conclusion

High ambient temperature negatively affects sperm quality, including decreased semen volume, sperm count, sperm concentration, motility and normal morphology. This might lead to protective strategies to avoid the adverse effects of high ambient temperature on male fertility.

A cohort study on factors impairing semen quality in transgender women

BACKGROUND

Transgender women (people assigned male genders at birth with female gender identities) can choose to cryopreserve semen before their medical transition, to retain the possibility to parent genetically related offspring later in life. Our previous retrospective study showed that semen quality in transgender women was decreased compared with the general population. The etiology of this impaired semen quality remains largely unknown. However, impaired semen quality might be related to habitual behavior more typically observed in transgender women, for example, the desire to hide their testicles because of genital dysphoria. Therefore, we decided to conduct a consecutive study with prospectively obtained data on behavior and lifestyle in transgender women.

OBJECTIVE

This study aimed to study the influence of a low ejaculation frequency, wearing tight undergarments, and bringing the testes in the inguinal position (tucking) on semen quality in transgender women at the time of fertility preservation.

STUDY DESIGN

In this cohort study, transgender women were included between May 2018 and September 2020, at the time of fertility counseling, before the start of hormonal treatment. Data were collected on demographics, lifestyle factors, medical history, endocrine laboratory results, and semen parameters. Semen parameters were categorized using reference values for human semen of the World Health Organization and compared with semen quality in the general population. The odds ratios with 95% confidence intervals were calculated using multivariable logistic regression analysis to assess the impact of tucking, wearing tight undergarments, and a low ejaculation frequency on semen quality, correcting for potential confounders.

RESULTS

Overall, 113 transgender women were included. Median semen parameters were significantly decreased than the general population. Crude logistic regression analyses showed an association between always wearing tight undergarments (odds ratio, 3.06; 95% confidence interval, 1.11-8.49) and extensive tucking (odds ratio, 6.09; 95% confidence interval, 1.54-24.01) on having a total motile sperm count of <5 million. Multivariable analyses showed that the association with tucking was independent of demographic factors, lifestyle factors, and medical history (odds ratio, 7.95; 95% confidence interval, 1.66-37.99). However, this was not the case for the association with always wearing tight undergarments (odds ratio, 2.89; 95% confidence interval, 0.95-8.82). Ejaculation frequency did not influence total motile sperm count.

CONCLUSION

Behavioral factors, including wearing tight undergarments and extensive tucking, may contribute to the lower semen quality in transgender women. These results will enable optimization of fertility counseling on how to adjust lifestyle before pursuing semen cryopreservation.

Responses and coping methods of different testicular cell types to heat stress: overview and perspectives

To facilitate temperature adjustments, the testicles are located outside the body cavity. In most mammals, the temperature of the testes is lower than the body temperature to ensure the normal progression of spermatogenesis. Rising temperatures affect spermatogenesis and eventually lead to a decline in male fertility or even infertility. However, the testes are composed of different cell types, including spermatogonial stem cells (SSCs), spermatocytes, spermatozoa, Leydig cells, and Sertoli cells, which have different cellular responses to heat stress. Recent studies have shown that using different drugs can relieve heat stress-induced reproductive damage by regulating different signaling pathways. Here, we review the mechanisms by which heat stress damages different cells in testes and possible treatments.

Heat stress response of somatic cells in the testis

The testis is a temperature-sensitive organ that needs to be maintained 2-7 °C below core body temperature to ensure the production of normal sperm. Failure to maintain testicular temperature in mammals impairs spermatogenesis and leads to low sperm counts, poor sperm motility and abnormal sperm morphology in the ejaculate. This review discusses the recent knowledge on the response of testicular somatic cells to heat stress and, specifically, regarding the relevant contributions of heat, germ cell depletion and inflammatory reactions on the functions of Sertoli and Leydig cells. It also outlines mechanisms of testicular thermoregulation, as well as the thermogenic factors that impact testicular function.

Adolescent Transgender Females Present Impaired Semen Quality That Is Suitable for Intracytoplasmic Sperm Injection Even Before Initiating Gender-Affirming Hormone Treatment

The present study aimed to determine the semen quality and cryopreservation outcomes among adolescent transgender females at the time of fertility preservation (FP) before initiating gender-affirming hormone (GAH) treatment. This retrospective cohort study included 26 adolescent transgender females who underwent FP in our Fertility Institute between 06/2013 and 10/2020. Pre-freezing semen parameters were compared to WHO 2010 reference values. Post-thaw semen parameters were used to determine the adequate assisted reproductive technology (ART). A multivariate linear regression analysis was performed to assess the impact of medical and lifestyle factors on semen quality. The mean age at which adolescent transgender females underwent FP was 16.2 ± 1.38 years. The median values of all semen parameters in our study group were significantly lower compared to the WHO data, including volume (1.46 mL vs 3.2 mL, respectively, P = 0.001 ), sperm concentration (28 × 10⁶/mL vs 64 × 10⁶/mL, P < 0.001), total sperm number (28.2 × 10⁶ vs 196 × 10⁶, P < 0.001), total motility (51.6% vs 62%, P < 0.001), and normal morphology (2% vs 14%, P < 0.001). The frequency of semen abnormalities was teratozoospermia 72%, hypospermia 52%, oligozoospermia 28%, and azoospermia 4%. The median post-thaw total motile count was 0.17 × 10⁶/vial, and the quality was adequate only for ICSI in 87.7% of the thawed semen samples. No correlation was found between selected medical and lifestyle factors and poor semen parameters. Semen quality is strongly reduced among adolescent transgender females before hormone therapy and their stored sperm samples are suitable for intracytoplasmic sperm injection (ICSI) rather than conventional IVF/intrauterine insemination (IUI).

The Cardiometabolic Health Benefits of Sauna Exposure in Individuals with High-Stress Occupations. A Mechanistic Review

Components of the metabolic syndrome (i.e., hypertension, insulin resistance, obesity, atherosclerosis) are a leading cause of death in the United States and result in low-grade chronic inflammation, excessive oxidative stress, and the eventual development of cardiometabolic diseases (CMD). High-stress occupations (HSO: firefighters, police, military personnel, first responders, etc.) increase the risk of developing CMD because they expose individuals to chronic and multiple stressors (i.e., sleep deprivation, poor nutrition habits, lack of physical activity, psychological stress). Interestingly, heat exposure and, more specifically, sauna bathing have been shown to improve multiple markers of CMD, potentially acting as hormetic stressors, at the cellular level and in the whole organism. Therefore, sauna bathing might be a practical and alternative intervention for disease prevention for individuals with HSO. The purpose of this review is to detail the mechanisms and pathways involved in the response to both acute and chronic sauna bathing and collectively present sauna bathing as a potential treatment, in addition to current standard of care, for mitigating CMD to both clinicians and individuals serving in HSO.

Current Insights and Latest Updates in Sperm Motility and Associated Applications in Assisted Reproduction

Spermatozoon is a motile cell with a special ability to travel through the woman’s reproductive tract and fertilize an oocyte. To reach and penetrate the oocyte, spermatozoa should possess progressive motility. Therefore, motility is an important parameter during both natural and assisted conception. The global trend of progressive reduction in the number and motility of healthy spermatozoa in the ejaculate is associated with increased risk of infertility. Therefore, developing approaches for maintaining or enhancing human sperm motility has been an important area of investigation. In this review we discuss the physiology of sperm, molecular pathways regulating sperm motility, risk factors affecting sperm motility, and the role of sperm motility in fertility outcomes. In addition, we discuss various pharmacological agents and biomolecules that can enhance sperm motility in vitro and in vivo conditions to improve assisted reproductive technology (ART) outcomes. This article opens dialogs to help toxicologists, clinicians, andrologists, and embryologists in understanding the mechanism of factors influencing sperm motility and various management strategies to improve treatment outcomes.

Erectile Dysfunction is Predictive Symptom for Poor Semen in Newlywed Men in Japan

Introduction

As a continuous decline in semen concentration has been reported, the concept of male infertility has gained increased attention. Although several surveys of semen quality have been conducted in young men in general, no study has reported only on newlywed men.

Aim

The aim of this study was to evaluate semen quality and assess its characteristics in newlywed men.

Methods

This study included 564 men visiting our hospital or clinic for fertility screening just before their wedding or as newlywed men. Based on the World Health Organization criteria, the rates of men who did not have a semen volume of ≥1.5 mL, a sperm concentration of ≥15 million/mL, and a sperm motility rate of ≥40% were calculated. The characteristics of the poor semen findings group with any 1 of the 3 items of semen volume, sperm concentration, or sperm motility rate not reaching the reference value were evaluated.

Main Outcome Measure

Independent factors, which are involved in the poor semen findings group, were evaluated.

Results

The poor findings in semen volume, sperm concentration, and sperm motility were found in 11.0%, 9.2%, and 10.6%, respectively. The poor semen findings group included 143 men (25.4%) with any 1 of the 3 items not reaching the reference value. As compared to the normal group, age and body mass index were significantly higher, testicular volume was significantly smaller, and blood gamma-glutamyltransferase and fasting blood sugar levels were significantly higher in the poor semen findings group. Logistic multivariate analysis, including symptom questionnaire scores, blood biochemistry items, and endocrinological items, showed 3 independent factors were involved in the poor semen findings group: age, luteinizing hormone, and erection (Erection Hardness Score).

Conclusion

It was clarified that even among men beginning their attempts at pregnancy, semen findings were poor and erectile dysfunction was involved in poor semen quality in one-quarter of the men. Tsujimura A, Hiramatsu I, Nagashima Y, et al. Erectile Dysfunction is Predictive Symptom for Poor Semen in Newlywed Men in Japan. Sex Med 2019;8:21–29.

A randomized placebo-controlled trial to investigate the effect of lactolycopene on semen quality in healthy males

Purpose

Poor sperm quality is a major contributor to infertility in heterosexual couples, but at present there are few empirical therapies. Several studies have examined the role of dietary factors and data from randomized controlled trials suggest that oral antioxidant therapy can improve some sperm parameters. Health benefits of lycopene supplementation have been proposed for a variety of health conditions and here we examine whether it can help improve sperm quality. This study aimed to investigate the effect of 14 mg daily lactolycopene for 12 weeks on semen quality in healthy men.

Methods

Sixty healthy male participants were recruited and randomized to this double-blind, placebo-controlled parallel study and received either 14 mg/d lactolycopene or a placebo for 12 weeks. The primary endpoint was a change in motile sperm concentration. Secondary endpoints were all other aspects of sperm quality, including the level of sperm DNA damage.

Results

Fifty-six men completed the intervention and the level of plasma lycopene was significantly increased in the men randomized to receive lycopene supplementation. There was no significant change in the primary endpoint (motile sperm concentration) post-intervention (p = 0.058). However, the proportion of fast progressive sperm (p = 0.006) and sperm with normal morphology (p < 0.001) did improve significantly in response to lactolycopene intervention.

Conclusions

Supplementation with 14 mg/d lactolycopene improves sperm motility and morphology in young healthy men.

Clinical Trial Registry number and website

ISRCTN33248724 http://www.isrctn.com/ISRCTN33248724

Urinary bisphenol S concentrations: Potential predictors of and associations with semen quality parameters among men attending a fertility center

BACKGROUND

Bisphenol S (BPS) was introduced in the market as a potentially safer alternative to bisphenol A (BPA). However, there are limited studies on health effects of BPS and no epidemiologic studies on its relationship with male reproductive health outcomes, specifically semen quality.

OBJECTIVE

To investigate predictors of urinary BPS concentrations and its association with semen parameters among men attending a fertility center.

METHODS

This cross-sectional analysis included 158 men of couples seeking fertility treatment (2011-2017) contributing 338 paired semen and urine samples. At the time of sample collection, men completed a questionnaire on self-reported use of household products and food intake within the previous 24 h. Urinary concentrations of BPA, BPS and bisphenol F were quantified using isotope-dilution tandem mass spectrometry. Semen samples were analyzed following WHO guidelines. Multivariable mixed models were used to investigate predictors of urinary BPS concentrations and to evaluate associations between urinary BPS concentrations and semen parameters, using random intercept to account for correlation in outcomes across multiple observations per man and adjusting for abstinence time, specific gravity, age, body mass index (BMI), year of sample collection and BPA concentrations. Analyses were also stratified by BMI (≥25 vs <25 kg/m²).

RESULTS

Median (IQR) urinary BPS concentration was 0.30 (0.20, 0.90) μg/L, and 76% of samples had detectable (>0.1 μg/L) concentrations. Self-reported fabric softener and paint/solvent use as well as intake of beef and cheese within 24 h before urine collection were positively associated with BPS concentrations. Men with higher BPS concentrations also had significantly higher BMI. Lower semen parameters were found among men with detectable BPS concentrations, compared to men with non-detectable BPS [2.66 vs. 2.91 mL for volume (p = 0.03), 30.7 vs. 38.3 mil/mL for concentration (p = 0.03), 76.8 vs. 90.0 mil for total count (p = 0.09), 43.7 vs. 47.0% for motility (p = 0.06), and 5.42 vs. 6.77% for morphologically normal sperm (p = 0.24)]. Some associations of BPS with lower semen parameters were only found among men with a BMI ≥ 25 kg/m².

CONCLUSIONS

We identified dietary and lifestyle factors associated with BPS exposure, suggesting potential avenues for reducing exposures. We also observed negative associations between BPS and semen parameters, especially among overweight and obese men.

[Impact of lifestyle and environmental factors on male reproductive health]

The identification of potential environmental hazards may be clinically relevant in the diagnosis of male infertility. Knowledge about these factors will improve prevention of fertility disorders. Apart from drugs or factors related to lifestyle such as alcohol and tobacco smoke, various environmental and occupational agents, both chemical and physical, may impair male reproductive function. Reproductive toxicity may evolve at the hypothalamic-pituitary, testicular, or post-testicular level; endpoints comprise deterioration of spermatogenesis and sperm function as well as endocrine disorders and sexual dysfunction. With regard to the complex regulation of the male reproductive system, the available information concerning single exogenous factors and their mechanisms of action in humans is limited. This is also due to the fact that extrapolation of results obtained from experimental animal or in vitro studies remains difficult. Nevertheless, the assessment of relevant exposure to reproductive toxicants should be carefully evaluated during diagnostic procedures of andrological patients.