The Impact of Intense Exercise on Semen Quality

Impact of Reductive Stress on Human Infertility: Underlying Mechanisms and Perspectives

Antioxidants have a well-established effect on general health and are essential in preventing oxidative damage to cells by scavenging free radicals. Free radicals are thought to be neutralized by these substances, which include polyphenols, β-carotene, and vitamins C and E, reducing cellular damage. On the other hand, recent data indicates that consuming excessive amounts of antioxidants may have side effects. Apoptosis and cell signaling are two beneficial physiological processes that are affected by excessive supplementation. Other negative effects include paradoxical enhancement of oxidative stress and unbalanced cellular redox potential. Overdosing on particular antioxidants has been associated with increased medication interactions, cancer progression, and fatality risks. Additionally, the complex impacts they may have on fertility might be both useful and adverse, depending on the quantity and duration of usage. This review delves into the dual role of antioxidants and emphasizes the importance of employing antioxidants in moderation. Antioxidant overconsumption may disrupt the oxidative balance necessary for normal sperm and oocyte function, which is one of the potential negative effects of antioxidants on fertility in both males and females that are also investigated. Although modest usage of antioxidants is generally safe and useful, high levels of antioxidants can upset hormonal balance, impair sperm motility, and negatively impact the outcomes of assisted reproductive technologies (ART). The findings emphasize the need to use antioxidant supplements in a balanced way, the importance of further research to optimize their use in fertility treatments, and the importance of supporting reproductive health to avoid adverse effects.

Impact of heat waves on semen quality: A retrospective study in Argentina between 2005 and 2023

Heat waves, defined as periods with daily temperatures surpassing the historical average for a specific region, have become more frequent worldwide in recent years. Previous studies have reported a negative association between temperature and semen quality, but the focus has mainly been on Asian and European populations. The study included 54,926 men (18-60 years) undergoing routine semen analysis between 2005 and 2023 at CEUSA-LAEH andrology unit, in Buenos Aires, Argentina. Hourly temperature readings were provided by the Servicio Meteorológico Nacional. R programming (R Studio v2022.07.2) was used to define heat waves, calculate key characteristics, visualize results, and perform statistical tests at the IBYME laboratory. During the period studied, a total of 124 days had heat waves (defined after at least 3 consecutive days with 32.3 °C and 22 °C). Men exposed to heat waves during spermatogenesis exhibited lower sperm number (concentration and count; P < 0.0001) and decreased normal morphology (percentage of normal sperm and normal motile count; P < 0.05) compared to those not exposed. These differences were most pronounced between semen samples from years with several heat waves (2013, 2023) and none (2005, 2007, 2016), displaying 4-5 times higher fold changes (P < 0.05). Further analysis employing multiple regression revealed a significantly negative association between semen quality and heat wave length, suggesting that a prolonged exposure may be more detrimental than an acute exposure. Subsequent analysis focusing on prolonged exposure (≥6-days heat wave) during spermatogenesis revealed a negative (P < 0.05) association between early exposure (spermatocytogenesis: 64-90 days prior semen collection) and semen quality. This study underscores the negative association between early exposure to heat waves during sperm development and semen quality, raising concerns about its possible association with the worldwide declining male fertility. A comprehensive collaborative approach is crucial, involving global governmental policies, sustainable practices, and coordinated efforts across scientific, healthcare, and policy domains.

Intensity and type of physical activity and semen quality in healthy young men

OBJECTIVE

To study the relationship between intensity of physical activity (PA) and semen quality in healthy young men.

DESIGN

A prospective cohort study with repeated measures for each subject.

SETTING

Not applicable.

PATIENT(S)

Healthy high school and university students who did not regularly smoke tobacco, drink alcohol, or take drugs or medicine, with normal body mass index and abdominal circumference.

INTERVENTION(S)

The participants underwent urologic visit, fasting blood and semen sampling, and anthropometric measurements, and filled in the International Physical Activity Questionnaire, at enrollment and after 4 and 8 months. Duration and frequency of walking, moderate-intensity, and vigorous-intensity activities in the last week were assessed, and a score was computed for total PA.

MAIN OUTCOME MEASURE(S)

Semen specimens were taken at each visit through masturbation, after 3-5 days of abstinence, and analyzed by an expert urologist. Sperm concentration, total and progressive motility, and proportion of spermatozoa with normal morphology were measured. Linear and generalized linear mixed models with the Poisson family were fitted to assess the relationships between PA variables and sperm parameters, after adjusting for season, time, and study arm. The shape of the relationship was modeled through restricted cubic spline regression.

RESULT(S)

A total of 143 male subjects, aged 18-23 years (median, 20 years), were enrolled. They had a median PA of 1,960 (95% confidence interval, 1,055-3,182) Metabolic Equivalent of Tasks in min/wk. Statistically significant differences were found for total, progressive motility, and percent of cell with normal morphology across categories of total PA; the highest medians of total (47%) and progressive motility (34%) and of the percentage of normal morphology cells (7%) were found for medium PA. Positive associations of sperm total motility and normal morphology with medium levels of PA, and negative associations with walking and vigorous-intensity activity emerged. Spline regression analysis confirmed these findings, showing an inverse U-shape relationship, with the highest value of total motility and normal morphology for medium PA, and the lowest values for lower and higher activity.

CONCLUSION(S)

These findings support the present recommendations to practice moderate PA for health improvement, including semen quality.

Effects of Physical Activity on Fertility Parameters: A Meta-Analysis of Randomized Controlled Trials

PURPOSE

Augmented adiposity may negatively impact sexual sphere through its metabolic effects and its detrimental impact on reproductive hormones. Moreover, a dysregulated metabolic pathway may promote apoptosis among spermatogenic cells. Based on these premises, a relation between weights loss and ameliorate semen parameters seems beneficial. To investigate if physical activity may affect semen parameters and fertility rate, a systematic literature search on major dataset has been performed.

MATERIALS AND METHODS

The search terms included: "Assisted reproduction therapies," "fertility," "semen parameters," "sperm parameters," and "physical activity." This analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines and it was registered on PROSPERO (CRD42023384471). A total of 47 studies have been identified; 1 reference has been eliminated after duplication check. After preliminary screening 32 papers have been excluded. Considering the exclusion criteria, 15 full-text articles were evaluated for eligibility. After a full-text review, six studies published during a span of eight years (2014-2022) have been included in the meta-analysis. Semen parameters, pregnancy and birth rates were investigated. The revised Cochrane risk of bias tool (Rob2) has been used to check the risk of bias.

RESULTS

The number of patients enrolled in studies ranges from 17 to 521; in the end, a total of 1,637 patients have been enrolled in the study. Fertility parameters investigated were semen quality parameters and pregnancy rates and live births. A statistically significant relationship between physical exercise and sperm concentration (p=0.02), total sperm motility (p<0.01), total sperm count (p<0.01), normal morphology (p<0.01) has been established. Moreover, the study registered a statistically significant association within physical activity and total pregnancy rate (p<0.01) and live birth rate (p<0.01).

CONCLUSIONS

We demonstrated that physical activity is significantly associated with amelioration of semen parameters and may be crucial in improving or even reverting male infertility.

The Influence of Lifestyle on Male Fertility in the Context of Insulin Resistance-Identification of Factors That Influence Semen Quality

Background: Male fertility is known to have been negatively influenced by the progress of civilization. Another condition whose incidence has been on the increase for the same reason is insulin resistance (IR). In addition, men increasingly often resign from the pursuit of active forms of leisure, preferring more sedentary ones. Considering these trends, this aim of this study was to investigate the relationships between lifestyle factors, insulin resistance, and male fertility in men with and without the condition. A further aim was to select those lifestyle factors that would make it possible to predict the level of male fertility, especially when IR is concerned. Methods: This study was performed in a group of 73 participants, divided into groups based on their insulin resistance status. Their physical activity, diet, perceived stress, sleep quality, libido level, and duration of sexual abstinence were assessed on the basis of a number of parameters, including indices proposed by the authors. In addition, relevant anthropometric measurements were taken and tests related to glucose metabolism and semen quality were carried out. On the basis of these data, statistical tests were performed to establish or disprove relationships between lifestyle choices and semen quality, as measured my sperm motility. Results: The results of this study highlighted the associations between a number of parameters, i.e., micronutrient and vitamin intake, diet quality, body composition, insulin resistance, and the duration of sexual abstinence, and semen quality, as measured by sperm motility. Significantly, the presence or absence of IR was linked to male fertility. A multivariate model was developed, incorporating parameters such as the Matsuda index, vitamin intake, and sexual abstinence duration, to predict motility scores. Conclusions: This study underscores the negative impact of modern civilization's lifestyle choices on male fertility. Notably, vitamin and mineral consumption, especially from antioxidant-rich diets like the Mediterranean diet, emerged as key modifiable factors affecting fertility. Routine diagnostics for insulin resistance in fertility-related interventions is recommended. This study also highlights the importance of considering sexual abstinence duration during semen collection for accurate diagnostic results. Future research should focus on validating the proposed multivariate model and exploring the effects of lifestyle modifications, particularly vitamin supplementation, on fertility outcomes in men, especially in the context of IR.

Validation and measurement properties of the Male and Female Fertility Knowledge Inventories (MFKI and FFKI) in Iranian couples

BACKGROUND

One of the most important population challenges during the last three decades has been the significant decrease in the fertility rate worldwide. Since the validity and reliability of the Male and Female Fertility Knowledge Inventories (MFKI and FFKI) have not been determined in Iran, we conducted this study to assess psychometric characteristics of the MFKI and FFKI in couples in Tabriz and Urmia, Iran.

METHODS

This was a cross-sectional study, as the first part (quantitative phase) of a sequential explanatory mixed-method study. The current study was done on 1200 participants (600 women with their husbands) living in the northwestern region of Iran, between January 2023 and September 2023. The psychometric properties of the Persian version of the tool (MFKI and FFKI) were performed in 5 stages, including translation process, content validity, face validity, construct validity and reliability assesment.

RESULTS

In this study, the CVI, CVR, and impact scores of the MFKI tool were equal to 0.90, 0.88, 3.26 and CVI, CVR, and Impact scores of the FFKI tool were respectively equal to 0.95, 0.91 and 3.59, that it indicated a satisfactory level of content and face validity. Then, to check the construct validity, the results of the exploratory factor analysis of the MFKI tool on 13 items led to the identification of 3 factors, including Environment and reproductive health (ERH), Lifestyle factors (LSF) and Sperm quality (SQ), which explained 66% of the cumulative variance. The results of the exploratory factor analysis of the FFKI tool on 15 items led to the identification of 4 factors, including Reproductive health (RH), Lifestyle factors (LSF), Chance of conception (CHC) and Ovarian reserve and preservation (ORP), which explained 68% of the cumulative variance.

CONCLUSIONS

The findings of this study indicated that the Persian version of MFKI and FFKI has acceptable psychometric properties to measure the awareness of Iranian couples regarding fertility, which can be used as a screening tool for fertility knowledge by health care professionals and also as a reliable tool in research.

Association of diet and lifestyle factors with semen quality in male partners of Chinese couples preparing for pregnancy

BACKGROUND

Semen quality significantly influences conception, and its preservation is crucial for couples seeking pregnancy. We investigated dietary and lifestyle risk factors impacting semen quality.

METHODS

A total of 466 males from the Guangzhou Women and Children's Medical Center's pre-pregnancy consultation clinic were recruited between January 2021 and March 2023 for inclusion. Semen analysis was performed, and diet and lifestyle data were gathered via questionnaire. Logistic regression was utilized to examine the link between diet, lifestyle variables, and semen quality.

RESULTS

Smoking worsened progressive sperm motility (38.0% vs. 36.0%, t = 2.262; P = 0.049). Alcohol consumption impaired progressive motility (40.5 ± 17.8% vs. 34.7 ± 16.1%, t = 3.396; P < 0.001) and total motility (56.0% vs. 64.0%; P = 0.001). Using plastic beverage bottles for oil or seasonings lowered sperm concentrations (40.4% vs. 59.0% vs. 65.5%; P = 0.032). A sweet diet correlated with higher total sperm motility (55.0% vs. 60.0%, 62.0% vs. 63.2%; P = 0.017). Higher milk product intake improved sperm concentration (41.6106 vs. 63.7106 vs. 66.1*106; P = 0.021) and motility (54.5% vs. 56.0% vs. 63.0%; P = 0.033). More frequent egg consumption increased semen volume (3.1 mL vs. 3.8 mL vs. 4.0 mL; P = 0.038). Roughage intake enhanced sperm concentration (160.8106 vs. 224.6106; P = 0.027), and adequate sleep improved progressive sperm motility rate (35.4% ± 18.2% vs. 40.2 ± 16.3%, F = 3.747; P = 0.024) and total motility (52.7% vs. 61.5%; P = 0.013). The regression model showed that using plastic containers for condiments was a protective factor for semen volume (OR: 0.12; CI 0.03-0.55; P = 0.006), sperm concentration (OR: 0.001, CI 0.00-0.30; P = 0.012), and count (OR: 0.12, CI 0.03-0.48; P = 0.003). Milk and egg consumption were also protective for semen volume (OR: 0.18, CI 0.06-0.51; P = 0.001 and OR: 0.11, CI 0.03-0.55; P = 0.006, respectively), while sufficient sleep benefitted total sperm motility (OR: 0.47, CI 0.24-0.95; P = 0.034).

CONCLUSIONS

Smoking and drinking, type of condiment container, diet preference, sleep duration, and milk, roughage, and egg consumption may reduce semen quality.

[Male infertility, environment and lifestyle]

BACKGROUND

Since the 1970s, there has been a quantitative and qualitative decline in sperm parameters. The main hypothesis to explain such a rapid evolution is the involvement of environmental and behavioral phenomena.

METHODS

A bibliographic search limited to English and French literature in men published before 7/2023 was carried out on the links between fertility and pollution, xenobiotics, tobacco, narcotics, cannabis, alcohol, weight, sport, sedentary lifestyle, sleep and anabolics.

RESULTS

Profound changes in lifestyle have occurred over the past 50 years: reduced sleep time, sedentary lifestyle, dietary changes, tobacco consumption, use of narcotics and anabolics. These changes have a proven impact on spermogram parameters, and should be corrected in an effort to optimize reproductive health. Other environmental parameters: pollution, exposure to heavy metals, exposure to xenobiotics, phthalates and pesticides… will be more difficult to exclude from patients' daily lives, but deserve to be taken more into account.

CONCLUSION

This review should help the urologist to assess and counsel patients in order to improve their reproductive health. These factors should be routinely investigated in infertile men.

Male infertility

Clinical infertility is the inability of a couple to conceive after 12 months of trying. Male factors are estimated to contribute to 30-50% of cases of infertility. Infertility or reduced fertility can result from testicular dysfunction, endocrinopathies, lifestyle factors (such as tobacco and obesity), congenital anatomical factors, gonadotoxic exposures and ageing, among others. The evaluation of male infertility includes detailed history taking, focused physical examination and selective laboratory testing, including semen analysis. Treatments include lifestyle optimization, empirical or targeted medical therapy as well as surgical therapies that lead to measurable improvement in fertility. Although male infertility is recognized as a disease with effects on quality of life for both members of the infertile couple, fewer data exist on specific quantification and impact compared with other health-related conditions.

Impact of Physical Activity and Sedentary Behavior on Spontaneous Female and Male Fertility: A Systematic Review

BACKGROUND

Before pregnancy is recognized, ovulation, fertilization, and implantation must all occur. Physical activity and sedentary behavior may impact pregnancy success by altering each or all of these processes. The aim of this review was to review the association between physical activity and sedentary behavior with spontaneous female and male fertility.

METHOD

PubMed/MEDLINE, Web of Science, CINAHL, SPORTDiscus, and Embase were searched from inception to August 9, 2021. Eligible studies included randomized controlled trials or observational studies, published in English, describing an association between physical activity or sedentary behavior (exposures) and spontaneous fertility (outcome) among women or men.

RESULTS

Thirty-four studies from 31 unique populations were included in this review (12 cross-sectional studies, 10 cohort studies, 6 case-control studies, 5 randomized controlled trials, and one case-cohort study). Of the 25 studies among women, the majority identified mixed results (n = 11) or no association (n = 9) between physical activity and female fertility. Seven studies reported on female fertility and sedentary behavior, and 2 found sedentary behavior was associated with decreased female fertility. Of the 11 studies among men, most of the studies (n = 6) found that physical activity was associated with increased male fertility. Two of the studies reported on male fertility and sedentary behavior, and neither identified an association.

CONCLUSIONS

The association between spontaneous fertility and physical activity in both men and women remains unclear, and the association with sedentary behavior remains largely unexplored.

Mitochondria Quality Control and Male Fertility

Mitochondria are pivotal to cellular homeostasis, performing vital functions such as bioenergetics, biosynthesis, and cell signalling. Proper maintenance of these processes is crucial to prevent disease development and ensure optimal cell function. Mitochondrial dynamics, including fission, fusion, biogenesis, mitophagy, and apoptosis, maintain mitochondrial quality control, which is essential for overall cell health. In male reproduction, mitochondria play a pivotal role in germ cell development and any defects in mitochondrial quality can have serious consequences on male fertility. Reactive oxygen species (ROS) also play a crucial role in sperm capacitation, but excessive ROS levels can trigger oxidative damage. Any imbalance between ROS and sperm quality control, caused by non-communicable diseases or environmental factors, can lead to an increase in oxidative stress, cell damage, and apoptosis, which in turn affect sperm concentration, quality, and motility. Therefore, assessing mitochondrial functionality and quality control is essential to gain valuable insights into male infertility. In sum, proper mitochondrial functionality is essential for overall health, and particularly important for male fertility. The assessment of mitochondrial functionality and quality control can provide crucial information for the study and management of male infertility and may lead to the development of new strategies for its management.

Lifestyle, Insulin Resistance and Semen Quality as Co-Dependent Factors of Male Infertility

Infertility is a problem that affects millions of couples around the world. It is known as a disease of couples, not individuals, which makes diagnosis difficult and treatment unclear. Male infertility can have many causes, from mechanical ones to abnormal spermatogenesis or spermiogenesis. Semen quality is determined by a number of factors, including those dependent on men themselves, with the number of infertile men growing every year. These include, e.g., diet, physical activity, sleep quality, stress, among many others. As these factors co-exist with insulin resistance, which is a disease closely related to lifestyle, it has been singled out in the study due to its role in affecting semen quality. In order to examine connections between lifestyle, insulin resistance, and semen quality, a review of literature published from 1989 to 2020 in the following databases PubMed/Medline, EMBASE (Elsevier), Scopus, Web of Science, and Google Scholar was performed. Hence, semen quality, environment, and insulin resistance are interrelated, thus it is difficult to indicate which aspect is the cause and which is the effect in a particular relationship and the nature of possible correlations. Since the influence of lifestyle on semen quality has been extensively studied, it is recommended that more thorough research be done on the relationship between insulin resistance and semen quality, comparing the semen quality of men with and without insulin resistance.

The future of sperm: a biovariability framework for understanding global sperm count trends

The past 50 years have seen heated debate in the reproductive sciences about global trends in human sperm count. In 2017, Levine and colleagues published the largest and most methodologically rigorous meta-regression analysis to date and reported that average total sperm concentration among men from 'Western' countries has decreased by 59.3% since 1973, with no sign of halting. These results reverberated in the scientific community and in public discussions about men and masculinity in the modern world, in part because of scientists' public-facing claims about the societal implications of the decline of male fertility. We find that existing research follows a set of implicit and explicit assumptions about how to measure and interpret sperm counts, which collectively form what we term the Sperm Count Decline hypothesis (SCD). Using the study by Levine and colleagues, we identify weaknesses and inconsistencies in the SCD, and propose an alternative framework to guide research on sperm count trends: the Sperm Count Biovariability hypothesis (SCB). SCB asserts that sperm count varies within a wide range, much of which can be considered non-pathological and species-typical. Knowledge about the relationship between individual and population sperm count and life-historical and ecological factors is critical to interpreting trends in average sperm counts and their relationships to health and fertility.

Effects of Age and Lifelong Moderate-Intensity Exercise Training on Rats' Testicular Function

Aging is associated with testicular morphological and functional alterations, but the underlying molecular mechanisms and the impact of physical exercise are poorly understood. In this study, we examined the effects of age and lifelong moderate-intensity exercise on rat testis. Mature adults (35 weeks) and middle-aged (61 weeks) Wistar Unilever male rats were maintained as sedentary or subjected to a lifelong moderate-intensity treadmill training protocol. Testis weight and histology, mitochondrial biogenesis and function, and proteins involved in protein synthesis and stress response were evaluated. Our results illustrate an age-induced testicular atrophy that was associated with alterations in stress response, and mitochondrial biogenesis and function. Aging was associated with increased testicular levels of heat shock protein beta-1 (HSP27) and antioxidant enzymes. Aging was also associated with decreased mRNA abundance of the nuclear respiratory factor 1 (Nrf1), a key transcription factor for mitochondrial biogenesis, which was accompanied by decreased protein levels of the oxidative phosphorylation system (OXPHOS) complexes subunits in the testes of older animals. On the other hand, exercise did not protect against age-induced testicular atrophy and led to deleterious effects on sperm morphology. Exercise led to an even more pronounced decrease in the Nrf1 mRNA levels in testes of both age groups and was associated with decreased mRNA abundance of other mitochondrial biogenesis markers and decreased protein levels of OXPHOS complexes subunits. Lifelong moderate-intensity exercise training was also associated with an increase in testicular oxidative stress markers and possibly with reduced translation. Together, our results indicate that exercise did not protect against age-induced testicular atrophy and was not associated with beneficial changes in mitochondria and stress response, further activating mechanisms of protein synthesis inhibition.

Effects of exercise on donkey semen parameters and some physiological indices

To study the effects of exercise on donkey semen parameters, Dezhou donkey (Equus asinus) jackasses (n=18) were assigned to three groups: control (CN, n=6), one-hour exercise (1 h EX, n=6) and two-hour exercise (2 h EX, n=6) groups. They were exercised with a walking machine for 3 days/week for 8 weeks. Semen parameters and reproductive hormones were evaluated weekly. The heart rate, rectal temperature, blood haematology indexes and the body condition score (BCS) were also measured. Results showed that the ejaculation volume increased while the sperm concentration decreased after exercise. However, other sperm parameters were unaffected. Reproductive hormones at resting period were rarely affected by exercise. The red blood cell number increased (P=0.023), while the mean erythrocyte hemoglobin concentration decreased (P=0.045) after the 8-week exercise in the 2 h EX group compared with the CN. After the 8-week exercise, the resting heart rate of the two exercise groups decreased significantly compared with the CN. The BCS in the CN group increased after the experiment (P=0.024). In conclusion, we found that exercise had positive effects on some physiological indices but did not affect semen parameters expect for volume and concentration of the jackass.

Running exercise training-induced impact on oxidative stress and mitochondria-related apoptosis in rat's testicles

The current study has been designed to explore the effects of running exercise training protocols (ETPs), with different intensities, on testicular redox and antioxidant capacities. Moreover, the crosstalk between oxidative stress (OS) and mitochondria-related apoptosis was analysed. To this end, 24 Wistar rats were subdivided into sedentary control, low- (LICT), moderate- (MICT), and high (HICT)-intensity continuous running ETP groups. Following 8 weeks, the Johnsen score, sperm count, testicular malondialdehyde (MDA) content, total oxidant status (TOS), and redox biomarkers, including glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase (CAT) levels were evaluated. Additionally, the expression levels of Bcl-2, Bax, caspase-3, proteins involving in the mitochondria-related apoptosis, and the apoptotic index were analysed. The LICT and MICT running ETPs did not affect the spermatogenesis development, sperm count, and antioxidant and redox capacities. Accordingly, no significant changes were revealed in Bcl-2, Bax, and caspase-3 expression levels and apoptosis index compared to sedentary rats. In contrast, the HICT-induced rats showed a significant (p < 0.05) reduction in spermatogenesis development, sperm count, antioxidant and redox capacities versus control, LICT, and MICT groups. Moreover, the expression of Bcl-2 was decreased, while the Bax and caspase-3 expression levels were increased in the HICT-induced group. Finally, the apoptosis index was increased in the HICT group. In conclusion, the suppressed redox system after HICT can trigger the mitochondria-mediated ROS overload, result in OS condition in the testicular tissue, and reversely target the mitochondrial membrane permeability. All of these molecular alterations are suspected to initiate progressive mitochondria-related apoptosis after HICT.

Influence of physical activity on male fertility

Infertility is a worldwide issue impacting 15% of couples' population. Male-related infertility results in almost 50% of these cases. Considering lifestyle factors associated with infertility, here in this literature review article, we aimed to discuss training/sport effects on male-related infertility. Regarding this issue, human and animal model studies related to the subject were gathered and analysed. Exercise is well known as a general improving factor, however, excessive exercise can result in male infertility due to reduced hypothalamus-pituitary-gonadal axis (HPT) function, increased oxidative stress and chronic inflammation. Consequently, these underlying impacts result in a low testosterone production, and reduced semen quality, and can lead to infertility. In contrast, it has been revealed that exercise can improve male fertility status in lifestyle-induced infertility condition such as obesity and diabetes. Indeed, exercise, by increasing testicular antioxidant defence, reducing pro-inflammatory cytokines level and enhancing the steroidogenesis process, leads to improved spermatogenesis and semen quality in lifestyle-induced infertility. In fact, it seems that individual health status as well as exercise volume, intensity and duration are effective-involved co-factors that influence the impact that exercise will promote on male fertility. Regarding these findings, it is important to study exercise different impacts in further clinical trials in order to generate preservative guidelines for exercise and also considering exercise as a treatment option in lifestyle-induced disease management.

Ameliorative effect of aqueous Cissus populnea suspension on cotton seed-induced testicular damage in male Wistar rats

Background

Testicular damage is an important etiological factor in male infertility. Despite reported decline in global incidence of infertility over the past years, pockets of cases are still ironically noticed to occur in developing countries due to limitation of accessibility to advanced management methods, hence their resort to alternative herbal therapy.

Methods

Testicular damage was induced using cotton seed. Cissus populnea was cut into chunks, air-dried, pulverized, powdered and suspended in water. Thirty-two (32) matured male Wistar rats were randomly divided into 4 groups (Group 1–4) designated as control, 100 mg/kg C. populnea (CP), cotton seed meal (CSM) and CSM + CP groups, each consisting of 8 rats. Group 1 was fed with normal rat chow, Group 2 was fed with 100 mg/kg CP, and Group 3 was fed with CSM for 8 weeks. Rats in Group 4 were fed with CSM for 8 weeks and dosed with 100 mg/kg aqueous C. populnea suspension for another 8 weeks. At the expiration of test period, the rats were sacrificed, blood sample collected, and plasma obtained for luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone, estrogen, catalase, superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione (GSH) measurements. Semen was collected for analysis and testes harvested for histological studies.

Result

There is a significant decrease (p < 0.05) in plasma FSH, LH, testosterone, estrogen, GSH, catalase, SOD, and GPx in rats fed on CSM when compared with values obtained in the control and aqueous C. populnea suspension-fed rats. Seminal fluid analysis showed a significant reduction (p < 0.05) in the sperm count, motility, morphology, vitality, and non-vitality among rats fed with CSM when compared to control rats. The histologic features of the testes showed abnormal interstitial appearances and absent Leydig cells in many areas among cotton seed-fed rats. Improvements in reproductive hormones, sperm qualities, and histological features were observed to occur in CSM group following administration of aqueous C. populnea suspension.

Conclusion

Based on the findings from this study, it can be concluded that aqueous C. populnea suspension ameliorates cotton seed-induced hypothalamo-pituitary–testicular axis functional disruption and testicular damage.

Men's dietary patterns in relation to infertility treatment outcomes among couples undergoing in vitro fertilization

PURPOSE(S)

To evaluate the relationship of men's dietary patterns with outcomes of in vitro fertilization (IVF).

METHODS

This is a prospective cohort study including 231 couples with 407 IVF cycles, presented at an academic fertility center from April 2007 to April 2018. We assessed diet with a validated food frequency questionnaire and identified Dietary Pattern 1 and Dietary Pattern 2 using principal component analysis. We evaluated adjusted probability of IVF outcomes across the quartiles of the adherence to two dietary patterns by generalized linear mixed models.

RESULTS

Men had a median age of 36.8 years and BMI of 26.9 kg/m2. Women's median age and BMI were 35.0 years and 23.1 kg/m2, respectively. Adherence to Dietary Pattern 1 (rPearson=0.44) and Dietary Pattern 2 (rPearson=0.54) was positively correlated within couples. Adherence to Dietary Pattern 1 was positively associated with sperm concentration. A 1-unit increase in this pattern was associated with a 13.33 (0.71-25.96) million/mL higher sperm concentration. However, neither Dietary Pattern 1 nor Dietary Pattern 2 was associated with fertilization, implantation, clinical pregnancy, or live birth probabilities.

CONCLUSIONS

Data-derived dietary patterns were associated with semen quality but unrelated to the probability of successful IVF outcomes.

Physical Activity and Male Reproductive Function: A New Role for Gamete Mitochondria

Several studies demonstrated that some types of physical exercise might affect male reproductive potential, even though the potential mechanisms involved in the modulation of sperm quality remain poorly understood. Therefore, we propose a new role for gamete mitochondria as a key hub that coordinates molecular events related to the effects induced by physical exercise.

The Role of Exercise to Reduce the Impact of Diabetes in the Seminal Quality: A Systematic Review

Background and Objectives: One of the most relevant consequences of diabetes mellitus is the temporal or complete infertility which can happen in young individuals. Therefore, the current systematic review aimed to investigate the effects of exercise to reduce the impact of Type 2 Diabetes Mellitus (T2DM) in seminal quality and related parameters. Materials and Methods: A systematic search was conducted in Pubmed and Web of Science databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines (PRISMA). The inclusion criteria were: (1) the study included at least one experimental and one comparison group, (2) the sample of the study was comprised of humans or animals with diabetes mellitus, (3) an intervention based on physical exercise was conducted, and (4) the study reported variables related to the seminal quality. Results: A total of 115 articles were identified. However, only six accomplished the inclusion and exclusion criteria. This systematic review includes a sample size of 260 participants (180 rats and 80 humans). Intervention ranged from 6 to 14 weeks, with 3–6 days per week. All interventions performed endurance training (50–70% VO₂max or maximum heart rate). Physical exercise increased sperm count, motility, and morphology, as well as improved testosterone, Luteinizing Hormone (LH), and Follicle Stimulating Hormone (FSH) levels. Moreover, physical exercise intervention reduced the percentages of sperms with negative Tubular Differentiation Index (TDI) and Spermiogenesis Index (SPI), DNA fragmentation, and also ameliorated the diabetes-induced apoptosis and improved sperm apoptosis index. Conclusions: Physical exercise could ameliorate diabetic pathological effects on sperm quality and related parameters that cause infertility or subfertility conditions. However, further homogeneous studies are needed to confirm these findings.

Male infertility due to testicular disorders

CONTEXT

Male infertility is defined as the inability to conceive following 1 year of regular unprotected intercourse. It is the causative factor in 50% of couples and a leading indication for assisted reproductive techniques (ART). Testicular failure is the most common cause of male infertility, yet the least studied to date.

EVIDENCE ACQUISITION

The review is an evidence-based summary of male infertility due to testicular failure with a focus on etiology, clinical assessment, and current management approaches. PubMed-searched articles and relevant clinical guidelines were reviewed in detail.

EVIDENCE SYNTHESIS/RESULTS

Spermatogenesis is under multiple levels of regulation and novel molecular diagnostic tests of sperm function (reactive oxidative species and DNA fragmentation) have since been developed, and albeit currently remain as research tools. Several genetic, environmental, and lifestyle factors provoking testicular failure have been elucidated during the last decade; nevertheless, 40% of cases are idiopathic, with novel monogenic genes linked in the etiopathogenesis. Microsurgical testicular sperm extraction (micro-TESE) and hormonal stimulation with gonadotropins, selective estrogen receptor modulators, and aromatase inhibitors are recently developed therapeutic approaches for men with the most severe form of testicular failure, nonobstructive azoospermia. However, high-quality clinical trials data is currently lacking.

CONCLUSIONS

Male infertility due to testicular failure has traditionally been viewed as unmodifiable. In the absence of effective pharmacological therapies, delivery of lifestyle advice is a potentially important treatment option. Future research efforts are needed to determine unidentified factors causative in "idiopathic" male infertility and long-term follow-up studies of babies conceived through ART.

Effect of Nandrolone decanoate induced-oxidative stress on rat testes, prostate, and seminal vesicle: Biochemical, morphometric and histopathological studies

Nandrolone decanoate (Nd) is a highly abused androgenic-anabolic steroid among body builders. Even though it has weak androgenic effects, its prolonged use may have harmful impact on male reproductive system which needs to be evaluated. This study aimed to reinvestigate its possible oxidative stress induced alteration on male rat reproductive system. Twenty-eight male rats were divided into two groups. Nd treated group (n = 18) injected intramuscular with 10 mg/kg body weight once a week for four weeks. While, the control group (n = 10) was injected with physiologic saline by the same route for four weeks. Body weight was recorded for all rats and after animal dissection weight of testes, prostate and seminal vesicles were also recorded. The results showed that the average testicular weight was decreased in treated group compared to the control. The average weights of the prostate and seminal vesicles were increased compared to the control. Morphometric study revealed that in Nd treated group, there was a decrease in the width of seminiferous tubules and the height of spermatogenic cell layer compared to the control. Testicular degeneration was expressed by presence of spermatid giant cells, vacuolation, and degenerated spermatozoa. Tunnel technique showed scattered positive reaction among the spermatogenic cell layers and interstitial cells. Severe alterations of the prostate were expressed by benign prostate hyperplasia and retained secretions. Lipid peroxidation products (malonaldehyde concentration as ng/g of testicular tissue) were increased in treated group compared to the control and suggested the occurrence of oxidative damage. Nd induced severe alterations in the male genital organs were resulted from oxidative stress. It is concluded that the male genital organs are highly sensitive to the anabolic steroids and there is a high extent of reproductive risk associated with the use of AASs.

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.

Impact of environmental toxin exposure on male fertility potential

Idiopathic infertility is the most common individual diagnosis in male infertility, representing nearly 44% of cases. Research studies dating over the last half-century consistently demonstrate a decline in male fertility that is incompletely explained by obesity, known genetic causes, or diet and lifestyle changes alone. Human exposures have changed dramatically over the same time course as this fertility decline. Synthetic chemicals surround us. Some are benevolent; however, many are known to cause disruption of the hypothalamic-pituitary-gonadal axis and impair spermatogenesis. More than 80,000 chemicals are registered with the United States National Toxicology Program and nearly 2,000 new chemicals are introduced each year. Many of these are known toxins, such as phthalates, polycyclic aromatic hydrocarbons, aromatic amines, and organophosphate esters, and have been banned or significantly restricted by other countries as they carry known carcinogenic effects and are reproductively toxic. In the United States, many of these chemicals are still permissible in exposure levels known to cause reproductive harm. This contrasts to other chemical regulatory legislature, such as the European Union's REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) regulations which are more comprehensive and restrictive. Quantification of these diverse exposures on an individual level has proven challenging, although forthcoming technologies may soon make this data available to consumers. Establishing causality and the proportion of idiopathic infertility attributable to environmental toxin exposures remains elusive, however, continued investigation, avoidance of exposure, and mitigation of risk is essential to our reproductive health. The aim of this review is to examine the literature linking changes in male fertility to some of the most common environmental exposures. Specifically, pesticides and herbicides such as dichlorodiphenyltrichloroethane (DDT), dibromochloropropane (DBCP), organophosphates and atrazine, endocrine disrupting compounds including plastic compounds phthalates and bisphenol A (BPA), heavy metals, natural gas/oil, non-ionizing radiation, air and noise pollution, lifestyle factors including diet, obesity, caffeine use, smoking, alcohol and drug use, as well as commonly prescribed medications will be discussed.

Variance in Stallion Semen Quality among Equestrian Sporting Disciplines and Competition Levels

Simple Summary

Despite the increased demand for breeding stallions to be performing at elite levels of competition, little research has been conducted into how equestrian disciplines and competition level affect seminal quality. Using statistical analysis, we found that competing stallions have lower quality semen than non-competing stallions and competitive activity may have a greater negative impact on spermatogenesis than age. In addition, dressage stallions recorded improved semen characteristics when compared to show jumping and eventing stallions. Stallions at elite levels of competition recorded higher total sperm count and progressive motility compared to those competing at lower levels of competition. We suggest that appropriate management of the competition stallion may reduce the negative impacts which exercise can induce on semen quality.

Abstract

Most stallions within breeding programmes are expected to breed and compete concurrently. The exercising of stallions with regards to training regimes during the breeding season is a controversial subject. Daily exercise at low intensities is important for the mental and reproductive well-being of the stallion, however higher intensities of exercise, as seen in competing stallions, may have detrimental effects on seminal quality. To calculate if competition does affect semen quality, this study investigated the effect that equestrian discipline and timing of competition had on a range of stallion semen characteristics. This was a retrospective study that evaluated the seminal data of 1130 stallion semen collections from two UK based stud farms between 2009 and 2016. Competing stallion semen quality was significantly lower with regards to concentration (p < 0.05) and progressive motility (p < 0.05) than non-competing stallions. Semen volume was higher in competing stallions (p < 0.05) than non-competing stallions. There was a significant difference in seminal attributes among disciplines and competition levels (p < 0.05). The difference in semen quality among competing and non-competing stallions, as well as the difference among disciplines suggests endocrinological and physiological changes occur in relation to training intensity and competition.