Male Semen Quality Research Articles

Variability of Seminal Plasma Cadmium Concentrations and Its Associations with Semen Quality among Healthy Chinese Men Screened as Potential Sperm Donors

TPS 631: Metals and health 1, Johan Friso Foyer, Floor 1, August 27, 2019, 3:00 PM - 4:30 PM Background: Cadmium (Cd) is a well-documented toxic metal, which has demonstrated adverse effects on male semen quality in animal studies. However, the results from human studies are inconsistent, probably due to the high within-subject variability in measurements of Cd in biological specimens and semen quality parameters. Objectives: To characterize the variability of Cd concentrations in seminal plasma and assessed its associations with repeated measurements of semen quality among healthy men who came to the Hubei Province Human Sperm Bank for donations screening. Methods: The reproducibility of Cd concentrations in 232 seminal plasma samples collected from 93 men was assessed using the intraclass correlation coefficient (ICC). The associations of Cd in within-subject pooled seminal plasma (n=1156) with repeated measurements of semen quality parameters (n = 5619) were assessed using linear mixed models with an individual-specific random intercept. Semen analyses were conducted by qualified laboratory technologists following the guidelines of the World Health Organization, and Cd concentration was determined by inductively coupled plasma-mass spectrometry. Results: Cd was detected in > 85% of the seminal plasma specimens. Fair to good reproducibility (ICC = 0.71) was achieved for serial measurements of Cd. Compared with men in the lowest Cd quartile, men in the highest quartile of Cd had a reduced semen volume and total motility of 3.25% (95% CI: -6.29%, -0.20%; p for trend = 0.027) and -1.88% (95% CI: -3.82%, 0.10%; p for trend = 0.083), respectively. Similar results were achieved when modeling Cd concentration (log-transformed) as a continuous variable in cubic spline models. Conclusion: Cd in seminal plasma were relatively stable. Exposure to high Cd may adversely affect semen volume and motility. Future studies in a larger and general population are needed to verify our findings.

Systemic arterial hypertension leads to decreased semen quality and alterations in the testicular microcirculation in rats

Arterial hypertension is a cardiovascular disease that leads to important systemic alterations and drastically impairs normal organ function over time. Hypertension affects around 700 million men of reproductive age and hypertensive men present increased risk for reproductive disorders, such as erectile dysfunction. However, the link between arterial hypertension and male reproductive disorders is associative at best. Moreover, many studies have reported associations between decreased male fertility and/or semen quality and alterations to general male health. In this study we aim to investigate the effect of systemic high blood pressure in sperm quality, sperm functional characteristics and testicular physiology in a rat model. Hypertensive rats presented altered testicular morphology – mainly vascular alterations and impaired testicular vasomotion. Hypertensive rats also presented decrease in sperm concentration, DNA integrity and increased percentages of sperm with dysfunctional mitochondria, intracellular superoxide anion activity and abnormal morphology. This study provides mechanistic insights by which arterial hypertension affects the testes, evidencing the testes as another target organ for hypertension as well as its impact on sperm quality.

Tobacco smoking and semen quality in infertile males: a systematic review and meta-analysis

BackgroundNowadays, the total number of couples visiting an infertility clinic is on the rise. Tobacco smoking is considered one of the major factors leading to male infertility. In this study, we aimed to systematically investigate the impact of tobacco smoking on semen quality in infertile male participants.MethodsOnline databases (Cochrane Central database of Randomized Controlled Trials and the databases of MEDLINE and EMBASE respectively) were searched for relevant English publications that satisfied the inclusion and exclusion criteria of this analysis. The clinical endpoints which were assessed included semen parameters (oligozoospermia, asthenozoospermia, teratozoospermia, and azoospermia), morphological defects of spermatozoa and the hormones involved in reproduction. RevMan 5.3 software was used to analyze the data whereby mean difference (MD) and risk ratios (RR) with 95% confidence intervals (CI) were generated to represent the results.ResultsSixteen studies with a total number of 10,823 infertile male participants (5257 smokers and 5566 non-smokers) were included. Results of this analysis showed oligozoospermia to be significantly higher in smokers (RR: 1.29, 95% CI: 1.05–1.59; P = 0.02). Morphological defect of spermatozoa (MD: 2.44, 95% CI: 0.99–3.89; P = 0.001) was also significantly higher in smokers whereby significant head (MD: 1.76, 95% CI: 0.32–3.20; P = 0.02), neck (MD: 1.97, 95% CI: 0.75–3.18; P = 0.002) and tail (MD: 1.29, 95% CI: 0.35–2.22; P = 0.007) defects were observed. However, smoking did not affected the pH (MD: 0.04, 95% CI: [− 0.03–0.11]; P = 0.30) and motility (RR: 1.42, 95% CI: 0.97–2.09; P = 0.07) of spermatozoa. Additionally, tobacco smoking did not cause any dis-balance in hormones which were involved in reproduction.ConclusionsIn conclusion, with reference to the clinical endpoints which were studied in this analysis, tobacco smoking was associated with a lower sperm count and an increase in the number of morphological defects of spermatozoa. However, the pH and motility of spermatozoa as well as the production of hormones which were involved in reproduction were not affected in this population of infertile males.

Male Infertility Problem: A Contemporary Review on Present Status and Future Perspective

Semen quality plays a pivotal role in maintaining healthy fertilizing ability of spermatozoa. Male infertility is a rising global problem with an increasing declining in male semen quality among men living in Africa, Europe, North American, and Asia. Though the sperm acquire proactive mechanisms during spermatogenesis and their epididymal maturation, they still remain viable for toxic insult. Declining semen quality is a major contributor to infertility. Studies have postulated that different factors, such as exposure to pesticides, industrial chemicals, heavy metals, obesity, alcoholism, tobacco smoking, sedentary lifestyles, poor nutrient intake, oxidative stress, physiological factors, genetic factors can influence male fertility. Routine semen analysis and assays for sperm chromatin integrity are the most widely utilized and best studied adjunctive diagnostics in male infertility. Over the years, scientists have developed different treatment options for male infertility. Male infertility with known etiology can be treated successfully, but other causes like genetic factors require pragmatic approaches. This article summarizes protective mechanisms of spermatogenesis, causes, diagnosis, and both modern and traditional treatment approaches of male infertility. Further, this article highlights present issues and direction for future exploration of the male infertility problem.

Effect of modifiable risk factors on semen parameters

Objective: This article examines the potential effects of lifestyle factors on male reproductive health. Evidence of a global decline in human sperm quality over recent decades has been accumulating. Environmental, occupational and modifiable lifestyle factors may contribute to this decline. This review focuses on key lifestyles factors such as diet, caffeine intake, tobacco chewing and alcohol intake. Method: A comprehensive literature search was performed to identify the major lifestyle factors associated with male infertility and semen quality. Database searches were limited to reports published in English only. Results: A prudent diet consists of high intake of fish, fruit, vegetables and legumes. Fat in diet is also as essential as other component of the diet. Although largely the evidence is observation based, evidence appears to support an approach of moderation carbohydrate and fats with better semen parameters. A good intake of antioxidants in diet and supplement correlates with higher sperm numbers and motility. The other very important modifiable factors are tobacco chewing, alcohol and caffeine intake. Nicotine in tobacco is found to suppress sperm progressive motility; it also reduces the percentage of viable spermatozoa and increases the altered chromatin compactness. Alcohol consumption leads to increased testosterone level due to change in oxidation metabolism of steroids in liver. Alcohol oxidation increases the Nicotinamide adenine dinucleotide (NAD) ratio which causes the re-dox state in favour of conversion of androstenedione into the reduced steroids testosterone and oestradiol. Caffeine intake has been associated with sperm DNA defects, aneuploidy and DNA breaks. Conclusion: The major lifestyle factors discussed in the present review are the potential issues that can possibly impair male infertility. However, their negative impact can be overcome by behavioural modification and better lifestyle changes.

Clonal diversity of Ureaplasma species and its relationship with oligozoospermia and semen quality in Chinese infertile males.

Whether Ureaplasma spp. are a causative agent of male infertility remains controversial. Previous studies concerning Ureaplasma spp. and male infertility have been confined to the species level of Ureaplasma. Currently, an expanded multilocus sequence typing (eMLST) scheme has been established with high discriminatory power. The aim of this study was to use eMLST to explore the distribution of Ureaplasma spp. and to analyze its role in oligozoospermia and semen quality. A total of 480 semen samples were obtained from Chinese infertile males. The associations between Ureaplasma spp. with oligozoospermia and semen characteristics were further evaluated. Phylogenetic analysis revealed that 102 Ureaplasma spp. could be separated into two clusters and seven sub-groups. Within cluster I (U. parvum), eST16 and eST41 were the most frequent clones. For cluster II (U. urealyticum), eST82 and eST147 were the most prevalent clones. Sub-groups A and C belonging to cluster I and sub-group 1 belonging to cluster II showed an association with oligozoospermia, in contrast with the Ureaplasma spp. negative group (P< 0.05). Compared with the negative group, semen motility decreased in sub-group 2, especially for non-progressive motility (P< 0.05). These results indicated that sub-groups A and C belonging to cluster I (U. parvum) and sub-group 1 belonging to cluster II (U. urealyticum) were shown to be associated with oligozoospermia. Sub-group 2 belonging to cluster II may have the ability to impair semen motility, especially for non-progressive motility.

Fenvalerate decreases semen quality in puberty rat through germ cell apoptosis.

Fenvalerate, a widely used synthetic pyrethroid insecticide, may adversely affect semen quality in males, but the possible mechanism remains unclear. In our study, forty male SD rats were randomly divided into one control group and three treatment groups administered with fenvalerate (0.02, 1 and 50mgkg-1 day-1 ) by gavage from post-natal day 28 (PND 28) to PND 88. Semen quality parameters were measured by computer-assisted sperm analysis, histological changes in testes were observed by hematoxylin-eosin (HE) staining, germ cell apoptosis was measured by TdT-mediated dUTP Nick-End Labeling (TUNEL) and caspases protein levels were measured by western blotting. Results showed that the increased body weight, the relative testis weight, the sperm concentration and the sperm motility were all significantly reduced in the 50mgkg-1 day-1 fenvalerate group. Increased inner diameter of seminiferous tubules and disturbed array of spermatogenic cells in testicular were observed in fenvalerate exposure groups. Meanwhile, TUNEL-positive germ cells significantly increased in 1 and 50mgkg-1 day-1 fenvalerate exposure groups, and the expression of caspase-8 and caspase-3 in rat testes were also significantly up-regulated. Taken together, our results indicate that fenvalerate has an adverse effect on semen quality, which may be related to germ cell apoptosis.

Effects of saturated palmitic acid and omega-3 polyunsaturated fatty acids on Sertoli cell apoptosis

ABSTRACTObesity is believed to negatively affect male semen quality and is accompanied by dysregulation of free fatty acid (FFA) metabolism in plasma. However, the implication of dysregulated FFA on semen quality and the involvement of Sertoli cells remain unclear. In the present study, we report obesity decreased Sertoli cell viability through dysregulated FFAs. We observed an increased rate of apoptosis in Sertoli cells, accompanied with elevated FFA levels, in the testes of obese mice that were provided a high-fat diet (HFD). Moreover, the levels of reactive oxygen species were elevated. Furthermore, we demonstrated by in vitro assays that saturated palmitic acid (PA), which is the most common saturated FFA in plasma, led to decreased cell viability of TM4 Sertoli cells in a time- and dose-dependent manner. A similar finding was noted in primary mouse Sertoli cells. In contrast to saturated FFA, omega-3 (ω-3) polyunsaturated fatty acids (PUFAs) protected Sertoli cells from PA-induced lipotoxicity at the physiologically relevant levels. These results indicated that the lipotoxicity of saturated fatty acids might be the cause of obesity-induced Sertoli cell apoptosis, which leads to decreased semen quality. In addition, ω-3 PUFAs could be classified as protective FFAs.Abbreviations: FFA: free fatty acid; HFD: high-fat diet; SD: standard diet; PA: palmitic acid; PUFA: polyunsaturated fatty acid; AI: apoptotic index; MTT: 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide; ROS: reactive oxygen species; HE: Hematoxylin and eosin; WT1: Wilm Tumor 1; NAFLD: non- alcoholic fatty liver disease; DCFH-DA: 2ʹ, 7ʹ dichlorofluorescin diacetate; 36B4: acidic ribosomal phosphoprotein P0; SD: standard deviation; EPA: eicosapentaenoic acid; PI: propidium iodide; DHA: docosahexenoic acid.

PM2.5 induces male reproductive toxicity via mitochondrial dysfunction, DNA damage and RIPK1 mediated apoptotic signaling pathway

Recent years, air pollution has been a serious problem, and PM2.5 is the main air particulate pollutant. Studies have investigated that PM2.5 is a risky factor to the deterioration of semen quality in males. But, the related mechanism is still unclear. To explore the effect of PM2.5, Sprague Dawley (SD) rats were exposed to PM2.5 (0, 1.8, 5.4 and 16.2mg/kg.bw.) through intratracheal instillation. The exposure was performed once every 3days and continued for 30days. In vitro, GC-2spd cells were treated using 0, 50, 100, 200μg/mL PM2.5 for 24h. The data showed that sperm relative motility rates and density were remarkably decreased, while sperm malformation rates were significantly increased with exposure to the PM2.5. The expression of Fas/FasL/RIPK1/FADD/Caspase-8/Caspase-3 and the level of 8-OHdG expression in testes were significantly increased after exposure to PM2.5. Additionally, in vitro the results showed that PM2.5 inhibited cell viability, increased the release of lactate dehydrogenase (LDH) by increasing reactive oxygen species (ROS) level. And ROS induced-DNA damage led to cell cycle arrest at G0/G1 phases and proliferation inhibition. Similar to the vivo study, the expressions of Fas/FasL/RIPK1/FADD/Caspase-8/Caspase-3 in GC-2spd cells were significantly increased after exposure to PM2.5 for 24-h. In addition, PM2.5 decreased the levels of ATP by impairing mitochondria structures, which led to energy metabolism obstruction resulted in the decrease of sperm motility. The above three aspects together resulted in the decrease in sperm quantity and quality.

Male obesity and semen quality: Any association?

Infertility as well as obesity are risng global concern. Whilst there is an established association between female obesity and infertility, a similar link is yet to be proven in men. To determine the effects of elevated body mass index (BMI) on semen quality among male partners of infertile couples attending an infertility clinic. In this cross-sectional study, 206 men who met the inclusion criteria were recruited for the study. Selected participants were grouped according to their BMI (kg/m2): normal BMI (18.5-24.9 kg/m2) and elevated BMI (≥25 kg/m2). The effect of weight on semen quality was assessed based on sperm count, percentage motility, and morphology. The number of participants with normal BMI was 110 (53.4%) while those with elevated BMI were 96 (46.6%). Of the participants in elevated BMI group, 52 (25.2%) were overweight and 44 (21.4%) were obese. There was no statistically significant difference in the semen quality as well as the pattern of semen parameter abnormalities between males with normal and elevated BMI (overweight or obese) (p=0.813). Elevated BMI did not significantly influence semen quality.

Lifestyle causes of male infertility

ObjectiveTo examine the potential effects of lifestyle factors on male reproductive health. Evidence of a global decline in human sperm quality over recent decades has been accumulating. Environmental, occupational, and modifiable lifestyle factors may contribute to this decline. This review focuses on key lifestyle factors that are associated with male infertility such as smoking cigarettes, alcohol intake, use of illicit drugs, obesity, psychological stress, advanced paternal age, dietary practices, and coffee consumption. Other factors such as testicular heat stress, intense cycling training, lack of sleep and exposure to electromagnetic radiation from mobile phone use are briefly discussed. Materials and methodA comprehensive literature search was performed to identify and synthesise all relevant information, mainly from within the last decade, on the major lifestyle factors associated with male infertility and semen quality. Database searches were limited to reports published in English only. A manual search of bibliographies of the reports retrieved was conducted to identify additional relevant articles. ResultsIn all, 1012 articles were identified from the database search and after reviewing the titles and abstract of the reports, 104 articles met the inclusion criteria. Of these, 30 reports were excluded as the full-text could not be retrieved and the abstract did not have relevant data. The remaining 74 reports were reviewed for data on association between a particular lifestyle factor and male infertility and were included in the present review. ConclusionThe major lifestyle factors discussed in the present review are amongst the multiple potential risk factors that could impair male fertility. However, their negative impact may well be mostly overcome by behaviour modification and better lifestyle choices. Greater awareness and recognition of the possible impact of these lifestyle factors are important amongst couples seeking conception.

Exposures to Atmospheric PM10 and PM10-2.5 Affect Male Semen Quality: Results of MARHCS Study.

Studies have shown that the effects of ambient particulate matter (PM) may be related to particle's size. However, results on the relationships between different PM and reproductive health are controversial. To explore the impacts of various PM fractions on male reproductive health, a total of 796 eligible subjects recruited in 2013 baseline investigation. In addition, there were 656 (82.4%) and 568 (71.3%) subjects participated follow-up surveys in 2014 and 2015, respectively. We used multivariable regression analysis and mixed-effect model to investigate the associations between air pollutants PM10, PM10-2.5, and PM2.5 exposures and semen quality, sperm DNA fragmentation and serum reproductive hormones of subjects. In the preliminary regression analysis, PM10, PM10-2.5, and PM2.5 exposure all associated with sperm concentration, morphology, sperm high DNA stainability (HDS), serum estradiol and testosterone levels. However, in mixed models, we only found that PM10 exposure were negatively associated with sperm normal morphology (95% CI: -14.13, -24.47) but positively associated with sperm progressive motility (95% CI: 23.00, 8.49), and PM10-2.5 exposure was inversely associated with sperm concentration (95% CI: -9.06, -27.31) after multiplicity adjustment. Our results provide the evidence that air PM10 and PM10-2.5 exposures, not PM2.5, are risk factors of semen quality.

Impact of Obesity on Male Subfertility and Semen Quality: A Cross- Sectional Study

Impact of Obesity on Male Subfertility and Semen Quality: A Cross- Sectional Study

The reproductive toxicology of male SD rats after PM2.5 exposure mediated by the stimulation of endoplasmic reticulum stress

Evidence has shown that exposure to fine particulate matter (PM) contributed to poor semen quality in males. However, the reproductive toxicity and relevant molecular mechanisms of Particular Matter 2.5 (PM2.5) from different seasons are not well understood. In the present work, we intend to investigate the toxic effects of PM2.5 during summer and winter on reproductive cells and tissues and focus on endoplasmic reticulum stress (ERS) to illustrate the possible molecular mechanisms. Sprague Dawley (SD) rats were exposed to PM2.5 from the summer season (0.2, 0.6, and 1.5 mg/kg b. w.) and winter (0.3, 1.5, and 2.7 mg/kg b. w.) through intratracheal instillation. The exposure was performed once every 3 days and continued for 2 months. Sperm and reproductive organs (testis and epididymis) were collected from the animals to conduct toxicity evaluation and mechanism analysis. The data showed that sperm relative motility rates were remarkably decreased, while sperm malformation rates were significantly increased with exposure to the summer and winter PM2.5. In particular, the reproductive toxicity of winter PM2.5 in the highest dose group was significantly greater than that in the other PM2.5 exposure groups. The pathological results also showed that the rats in the winter PM2.5 group of 2.7 mg/kg b. w. had severe testicular tissue injury, as determined by haematoxylin and eosin (HE) staining. The apoptotic results obtained by terminal dUTP nick-end labelling (TUNEL) further suggested that summer and winter PM2.5 exposure promoted the testicular germ cell apoptosis. The reproductive toxicity of winter PM2.5 in the testis was stronger than that of summer PM2.5. In addition, the expressions of GRP78 and XBP-1, biomarkers of ERS, was enhanced under the conditions of PM2.5 exposure, and ERS-mediated apoptosis through the upregulation of CHOP and Caspase-12 in the epididymis and testis was activated. In conclusion, PM2.5 exposure induced reproductive toxicity in male SD rats by the stimulation of ERS.

Male urinary paracetamol and semen quality.

The endocrine-disrupting properties of paracetamol have been previously demonstrated in rodent studies of abnormal sperm morphology and diminished testosterone production, in addition to epidemiologic studies of diminished couple fecundity. In this study, we examined the relationship between paracetamol and its metabolite p-aminophenol quantified in a single spot urine and semen quality among 501 male partners of couples planning for pregnancy. Men provided a urine specimen and two fresh semen samples collected approximately one month apart and underwent 24-h analysis for 35 semen quality parameters. Paracetamol and p-aminophenol were quantified in urine by ultra-high-performance liquid chromatography coupled with an electrospray triple quadrupole mass spectrometry. The relationship between natural-log-transformed urinary paracetamol and p-aminophenol rescaled by their standard deviation and 21 Box-Cox-transformed, 14 non-transformed semen parameters was assessed using linear mixed-effects models. The median concentrations (IQR) of urinary paracetamol and p-aminophenol were 15.5ng/mL (5.44, 73.5) and 978ng/mL (500, 1596), respectively. Following adjustment for creatinine and age, a 1-standard deviation increase in log-transformed urinary paracetamol was associated with a reduction in beat cross-frequency and an increase in DNA fragmentation [β (95% CI): -0.59Hz (-1.16, -0.03) and 0.05% (0.01, 0.09), respectively]. These findings were corroborated in models of categorical chemical concentrations; higher concentrations of paracetamol remained associated with reduced beat cross-frequency and increased DNA fragmentation. A 1-standard deviation increase in log-transformed urinary p-aminophenol was associated with a reduction in sperm head area [β (95% CI): -0.1 μm2 (-0.18, -0.02) and width -0.02 μm (-0.04, -0.01)]. However, only the association with sperm head area remained statistically significant in models of p-aminophenol quartiles. Our findings suggest that adult male urinary paracetamol is associated with sperm motility and DNA fragmentation, while the metabolite, p-aminophenol, is predominantly associated with sperm head morphometry.

Racial Variation in Semen Quality at Fertility Evaluation

To identify racial differences in semen quality among men living in the same geographic area and seeking fertility evaluation. Men obtaining a semen analysis for infertility evaluation or treatment between 2012 and 2016 at a single center were identified, and demographic data including height, weight, body mass index (BMI), and age were described. Mean semen parameters and the proportions of men with suboptimal parameters based on the World Health Organization's fifth edition criteria were also compared based on race. Multivariable regression analysis was conducted incorporating age, BMI, and year of evaluation. Further subanalyses based on BMI were subsequently performed. White men produced greater volumes of semen on average; however, Asian men had higher sperm concentrations and total sperm count. A lower proportion of Asian men compared to white men had semen quality in the suboptimal range for most semen parameters, whereas a higher proportion of white men were found to have azoospermia. Stratification by BMI groups attenuated the observed differences between whites and Asians, yet Asian male semen quality remained higher. Among men evaluated for infertility at a single center, Asians had lower volume but higher sperm concentrations compared with whites, which was influenced by differences in azoospermia prevalence. Although anthropometric and demographic factors attenuated the differences, even after adjustment, the contrasts remained. Our study suggests that racial differences exist in semen quality at the time of infertility evaluation.

Male birthweight, semen quality and birth outcomes.

What are the relations among birthweight (BW), semen parameters and birth outcomes in a population-based sample? BW is unrelated to semen parameters, which are in turn unrelated to birth outcomes. In clinical settings, there has been suggestion that semen parameters are related to BW when comparing fertile and infertile men; however, findings have been less clear in more general populations. Questionnaire data and semen samples were collected at baseline from 427 male participants of the population-based Longitudinal Investigation of Fertility and the Environment (LIFE) prospective cohort study from 2005 to 2009, who were followed prospectively to assess pregnancy outcomes among 226 singleton births. Men of at least 18 years of age who were married or in a committed relationship and trying to conceive were eligible for participation; physician-diagnosed infertility was an exclusion criterion. Participants were recruited from two geographic areas and semen samples were analyzed for 34 quality parameters categorized as general, motility, morphology, sperm head and sperm chromatin structure using methods including computer-aided semen analysis integrated visual optical system and sperm chromatin structure assay. Linear and mixed models were used for statistical analysis of the relations between men's BW, semen parameters, and BW, gestational age at delivery, birth length, head circumference and ponderal index of singleton births. No association was observed between male BW and semen parameters or birth outcomes. Few associations were observed between semen parameters and birth outcomes, and the observed statistically significant associations were isolated and without a consistent pattern that would suggest an association between BW and birth outcomes. Men's BW was self-reported and may be subject to some imprecision. Semen analysis was performed the day after collection, an approach that impacts the assessment of motility and that may limit inference from our analyses of motility measures. In addition, inclusion criteria for selection into the cohort limits generalizability to generally healthy couples trying to conceive and without known subfertility. Despite suggestions from prior studies of male in utero exposures impacting BW and male reproductive health, there appears to be little support for such relations in this generally healthy population. Supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (N01-HD-3-3355, N01-HD-3-3356 and NOH-HD-3-3358). The authors report no competing interests, and a Memo of Understanding with the National Institute of Occupational Safety and Health (NIOSH) for semen analysis. Not applicable.

Effect of chronic glomerulonephritis on the semen quality and cytokines in the semen of infertile males.

The effects of chronic glomerulonephritis (CGN) on semen quality and cytokine levels in the semen of infertile males remain undetermined. Fifty-eight semen samples from normal males and CGN males with and without infertility, respectively, were analyzed. Semen volume, semen pH, sperm density, percentage of forward movement of sperm, sperm activate rate, sperm survival rate, and rate of normal sperm morphology of infertility males with CGN were significantly lower than those of CGN males without infertility and normal males (P<.05). In addition, the blood urea nitrogen and serum creatinine levels and interleukin (IL)-17 and IL-18 levels in infertility males with CGN were significantly higher than those of CGN males without infertility and normal males (P<.05). CGN increased the blood urea nitrogen and serum creatinine levels, which induced abnormal expression of IL-17 and IL-18, and negatively affected male semen quality and might result in male infertility.

Anogenital distance is associated with serum reproductive hormones, but not with semen quality in young men.

Is anogenital distance associated with semen parameters and serum reproductive hormone levels in males? Anogenital distance is associated with serum reproductive hormones, but not with semen quality. Epidemiological studies have suggested that anogenital distance (AGD) may be associated with testicular dysfunction in adult men. However, the role of AGD in estimating male reproductive function remains unclear. We examined the associations between AGD and semen parameters and reproductive hormones levels in 656 young college students in a Male Reproductive Health in Chongqing College Students (MARHCSs) cohort study in June of 2014. In this study, two variants of AGD (AGDAP and AGDAS) were measured in 656 university students. Serum levels of testosterone (T), estradiol (E2), progesterone (P), prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), sex hormone-binding globulin (SHBG) and inhibin-B; and semen quality outcomes, including semen volume, sperm concentration, total sperm number, sperm progressive motility, total motility and morphology, were assessed. The associations between AGD and semen parameters/reproductive hormones levels were analyzed using multiple regression analysis. Both AGDAS and AGDAP were not associated with any semen parameters. In the non-parametric correlation analysis, AGDAP were correlated with sperm progressive motility and reproductive hormones of E2, testosterone, SHBG and the testosterone/LH ratio. However, body mass index (BMI) also significantly correlated with serum testosterone ( ITALIC! r = -0.216, ITALIC! P = <0.0001) and SHBG ( ITALIC! r = -0.229, ITALIC! P = <0.001). In the multiple regression models, AGDAP was negatively associated with the serum E2 level (95% CI, -0.198 to -0.043; ITALIC! P = 0.002) and positively associated with the ratio of T/E2 (95% CI, 0.004-0.011; ITALIC! P = 0.001) after an adjustment for BMI and other confounders. Using only a single semen sample to predict male reproductive function over a longer period is a potential limitation of the present study. The other limitation is the cross-sectional nature of the study design. Longitudinal data from an extended follow-up on a large cohort would be more definitive. Our results do not support previous studies where AGD is associated with male semen quality. The utility of AGD in predicting reproductive outcomes in adult males should thus be considered prudently. This study was supported by the Key Program of Natural Science Funding of China (no. 81130051), Young Scientist Program of NSFC (no. 81502788) and the National Scientific and Technological Support Program of China (no. 2013BAI12B02). None of authors had any competing interests to declare.

The Effects of Testosterone on Oxidative Stress Markers in Mice with Spinal Cord Injuries.

Spinal cord injury (SCI) causes infertility in male patients through erectile dysfunction, ejaculatory dysfunction, semen and hormone abnormalities. Oxidative stress (OS) is involved in poor semen quality and subsequent infertility in males with SCI. The aim of this study is to examine the effects of SCI on the level of testosterone hormone. In this experimental study, we evaluated the effects of exogenous testosterone on the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as the levels of malondialdehyde (MDA) and protein carbonylation (PCO), as markers of OS, in 10 groups of SCI mice. Total antioxidant capacity (TAC) was determined using the 2,29-azinobis-(3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) radical cation assay. Exogenous testosterone administration in mice with SCI significantly reduced SOD and GPx enzyme activities and MDA level. There was no significant decrease in PCO content. In addition, TAC remarkably increased in the sham and SCI groups not treated with testosterone but remained unchanged in all other experimental groups. Exogenous testosterone also reduced serum testosterone levels in all groups except the positive control group. Our cumulative data indicated that SCI could cause sterility by disturbing the plasmatic testosterone balance. The normal level of endogenous testosterone was not completely restored by exogenous testosterone administration.