Seminal plasma androgen/oestrogen balance in infertile men

Effects of Heat Stress-Induced Sex Hormone Dysregulation on Reproduction and Growth in Male Adolescents and Beneficial Foods

Heat stress due to climate warming can significantly affect the synthesis of sex hormones in male adolescents, which can impair the ability of the hypothalamus to secrete gonadotropin-releasing hormone on the hypothalamic-pituitary-gonadal axis, which leads to a decrease in luteinizing hormone and follicle-stimulating hormone, which ultimately negatively affects spermatogenesis and testosterone synthesis. For optimal spermatogenesis, the testicular temperature should be 2-6 °C lower than body temperature. Heat stress directly affects the testes, damaging them and reducing testosterone synthesis. Additionally, chronic heat stress abnormally increases the level of aromatase in Leydig cells, which increases estradiol synthesis while decreasing testosterone, leading to an imbalance of sex hormones and spermatogenesis failure. Low levels of testosterone in male adolescents lead to delayed puberty and incomplete sexual maturation, negatively affect height growth and bone mineral density, and can lead to a decrease in lean body mass and an increase in fat mass. In order for male adolescents to acquire healthy reproductive capacity, it is recommended to provide sufficient nutrition and energy, avoid exposure to heat stress, and provide foods and supplements to prevent or repair testosterone reduction, germ cell damage, and sperm count reduction caused by heat stress so that they can enter a healthy adulthood.

Taste receptor type 1 member 3 is required for the fertility of male mice

Male infertility is a global health concern. However, its underlying pathophysiology remains unclear. Taste receptor type 1 member 3 (TAS1R3) is highly expressed in the testes, indicating its potential involvement in male fertility. Using wild-type and Tas1r3 knockout (KO) mice, we investigated whether TAS1R3 modulates male reproductive function. Tas1r3 KO mice exhibited reduced male fertility compared to WT mice, with fewer live pups per litter and a delayed first litter. Testicular transcriptome analysis indicated suppressed PKA/CREB/StAR signaling-mediated testosterone synthesis in Tas1r3 KO mice. In silico single-cell RNA sequencing revealed considerably higher Tas1r3 expression in Leydig cells than in other testicular cell subtypes. An in vitro study validated that Tas1r3 knockdown downregulated the expression of Creb1 and steroidogenic genes in Leydig cells. Our results suggest that testicular TAS1R3 is intricately involved in male reproduction via the PKA/CREB/StAR signaling pathway, highlighting its potential as a promising target for addressing male infertility.

Heat stress upregulates aromatases expression through nuclear DAX-1 deficiency in R2C Leydig tumor cells

An appropriate balance between testicular testosterone and estradiol is required for spermatogenesis. Excess estradiol is often identified in the semen and serum of infertile men; however, the mechanisms behind this observation remain unclear. This study indicates the relationship between heat stress and aromatase synthesis in Leydig cells. We used R2C rat Leydig tumor cells, which can synthesize both testosterone and estradiol. Aromatase transcription was regulated by the PⅡ promoter with or without heat stress. Heat stress at 40 °C increased aromatase expression and decreased testosterone to estradiol ratio and nuclear DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1), which is a suppressor of steroidogenic factor 1 (SF-1). Leptomycin B and KPT-185, a nuclear export inhibitor, prevented nuclear DAX-1 deficiency induced by heat stress and inhibited aromatase transcription. These results indicate that heat stress interferes with DAX-1-SF-1 interaction and induces SF-1-dependent aromatase transcription.

The male infertility evaluation still matters in the era of high efficacy assisted reproductive technology

Today's reproductive endocrinology and infertility providers have many tools at their disposal when it comes to achieving pregnancy. In the setting of highly efficacious assisted reproductive technology, it is natural to assume that male factor infertility can be overcome by acquiring sperm and then bypassing the male evaluation. In this review, we go through guideline statements and a stepwise male factor infertility evaluation to propose that a thorough male evaluation remains important to optimize pregnancy and live birth. The foundation of this parallel evaluation is referral to a reproductive urologist for the optimization of the male partner, for advanced diagnostics and interventions, and for the detection of other underlying male pathology. We also discuss what future developments might have an impact on the workup of the infertile male.

The Fate of Leydig Cells in Men with Spermatogenic Failure

The steroidogenic cells in the testicle, Leydig cells, located in the interstitial compartment, play a vital role in male reproductive tract development, maintenance of proper spermatogenesis, and overall male reproductive function. Therefore, their dysfunction can lead to all sorts of testicular pathologies. Spermatogenesis failure, manifested as azoospermia, is often associated with defective Leydig cell activity. Spermatogenic failure is the most severe form of male infertility, caused by disorders of the testicular parenchyma or testicular hormone imbalance. This review covers current progress in knowledge on Leydig cells origin, structure, and function, and focuses on recent advances in understanding how Leydig cells contribute to the impairment of spermatogenesis.

Expression of G-Protein-Coupled Estrogen Receptor (GPER) in Whole Testicular Tissue and Laser-Capture Microdissected Testicular Compartments of Men with Normal and Aberrant Spermatogenesis

Simple Summary

Nowadays, there is no doubt that estrogens play an important role in male reproduction, affecting testicular cell differentiation, proliferation, apoptosis and metabolism. It is also widely believed that intratesticular balance of androgens and estrogens is crucial for the testicular development and function and that the increased testicular estrogen production may be associated with spermatogenic failure. There is also growing epidemiological evidence that the exposure of men to endocrine disruptors demonstrating estrogenic activity (xenoestrogens) may lead to impairment of male fertility via interference with estrogen signaling pathways. Besides the two classical nuclear estrogen receptors, the membrane-bound G protein-coupled estrogen receptor (GPER) was described in human testicular tissue. However, there are little data on its expression in testes with disturbed spermatogenesis. In this study, we investigated the GPER expression pattern in biopsies of azoospermic men with complete and aberrant spermatogenesis. Our results showed an increased expression of the GPER in testes with impaired spermatogenesis. Moreover, they indicate a possible involvement of estrogen signaling through GPER in disturbed function of Sertoli cells—the cells that support spermatogenic process.

Abstract

In this study, we retrospectively investigated GPER expression in biopsies of azoospermic men with complete (obstructive azoospermia—OA) and aberrant spermatogenesis (nonobstructive azoospermia—NOA). Each biopsy was histologically evaluated with morphometry. The testicular GPER expression was analyzed by the immunohistochemistry and RT-PCR technique in the whole testicular tissue and in seminiferous tubules and Leydig cells after laser-capture microdissection. In laser-microdissected compartments, we also analyzed transcriptional expression of selected Leydig (CYP17A1, HSD17B3, StAR) and Sertoli cell (AMH, SCF, BMP4) function markers. Immunohistochemical staining revealed expression of GPER in the cytoplasm of Leydig and Sertoli cells. Its stronger intensity was observed in Sertoli cells of NOA biopsies. The RT-PCR analysis of the GPER mRNA level unequivocally showed its increased expression in seminiferous tubules (i.e., Sertoli cells), not Leydig cells in NOA biopsies. This increased expression correlated positively with the transcriptional level of AMH—a marker of Sertoli cell immaturity, as well as FSH serum level in NOA but not in the OA group. Our results clearly demonstrate altered GPER expression in testes with primary spermatogenic impairment that might be related to Sertoli cell maturity/function.

"Seminal testosterone", rising viewpoint of local spermatogenesis in nonobstructive azoospermia: One center long-term bidirectional cohort study

OBJECTIVE

Reproductive hormones are a traditional good method to evaluate spermatogenesis but might not accurately represent local spermatogenesis. To find a more accurate method, seminal reproductive hormones were studied.

METHODS

A bidirectional cohort study was performed. A total of 126 infertile men from 2018 to 2019 were retrospectively analyzed. They were divided into nonobstructive azoospermia (NOA), oligozoospermia (OLZ) and normal (NOR) groups. A prospective study was conducted on patients in the NOA and OLZ groups for 2 years. Microscopic testicular sperm extraction was performed for NOA patients, who were divided into a focal spermatogenesis group (FS) and an idiopathic azoospermia group (IA). Drug treatment was for OLZ patients, who were divided into a valid group (VA) and an invalid group (IN). The differences in sperm parameters and reproductive hormones were compared. ANOSIM analysis was used between and within groups. Pearson correlation analysis, CO inertia analysis and Proctor's analysis were for relationships. ROC curve for the specificity and sensitivity. Time series analysis was for the trends between hormones and time.

RESULTS

The b-FSH, b-LH, s-T and ΔT in the NOA group were significantly higher than those in the OLZ and NOR groups. However, the s-FSH, s-E₂, s-P, ΔFSH, ΔLH, ΔP and ΔE₂ were lower. Thirty-one NOA patients underwent MTSE, of whom 12 had sperm (FS) and 19 had no sperm (IA). The s-FSH and s-E₂ of the FS group were higher than those of the IA group. Twenty-six OLZ patients completed 30 days of treatment, of which 11 had an improved sperm count (VA) and 15 had no (IN). The ΔT of the VA group was higher than that of the IN group. After follow-up for 2 years, 18 patients' results showed that b-FSH, b-LH and s-T were different over time, with delays of 19, 3 and -19 days. SC is closely related to pH, s-FSH, s-LH, s-E₂, s-P, s-T, b-FSH, b-LH, ΔFSH, ΔLH, ΔP, ΔE₂ and ΔT. There were complex common trends and relationships between different kinds of hormones. s-FSH, s-LH, s-E₂, s-P, s-T, b-FSH and b-LH were useful to judge spermatogenesis, of which s-T, b-FSH and b-LH were more sensitive. If s-T, b-FSH and b-LH reached 64.4, 9.4 and 4.7, respectively, their prediction performance was the strongest.

CONCLUSION

Seminal testosterone is sensitive for judging local spermatogenesis in nonobstructive azoospermia patients, which may be the direction of local spermatogenesis in nonobstructive azoospermia.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn/index.aspx, identifier ChiCTR2200060463.

Inverse association of certain seminal phthalate metabolites with semen quality may be mediated by androgen synthesis: A cross-sectional study from the South China

BACKGROUND

Several in vitro and in vivo studies have demonstrated the effects of phthalates on androgen synthesis, and the adverse outcomes of phthalate exposure on male reproductive function have been reported. However, the direct relationship among these three factors remains unknown.

OBJECTIVE

To explore the potential roles of steroids involved in androgen synthesis in the association between phthalate exposure and semen quality.

METHODS

Eighteen phthalate metabolites (mPAEs) and nine steroids were analyzed in semen samples of 403 male participants aged 18-54 years from a hospital in Shenzhen, China. The associations across phthalate metabolites, steroids, and eleven semen quality parameters were evaluated by multivariate linear regression and logistical regression models. The potential contributions of steroids to the associations between phthalate metabolites and semen quality outcomes were explored by mediation effect analysis.

RESULTS

In this cross-sectional study, mono-n-butyl phthalate (MnBP) was inversely associated with nine continuous semen quality parameters in a dose-dependent manner (all p for trend < 0.05). Positive associations were observed between MnBP tertiles and androstenedione (ADD) and pregnenolone (PGL), of which only ADD was significantly associated with sperm quality (i.e., motility, p < 0.05). The estimated average mediated effects of seminal ADD on the associations between MnBP and lower sperm motility parameters (i.e., total motility, TR; progressive motility, PR; curvi-linear velocity, VCL) were 6.4-11.9% (all p < 0.05). The potential mediated effects of ADD on the increasing risks of TR (9.8%) and PR (8.5%) abnormalities induced by MnBP exposure were also observed in logistical regression analysis.

CONCLUSION

Our results indicated that androgen synthesis in reproductive system may be potentially affected by phthalate exposure, thereby resulting in reduced sperm motility in adult men. Further studies are needed to understand the actual roles and underlying mechanism of action of androstenedione on these associations.

Testicular steroid sulfatase overexpression is associated with Leydig cell dysfunction in primary spermatogenic failure

BACKGROUND

Decreased testosterone (T) to LH ratio and increased 17β-estradiol (E2) serum concentrations represent a common finding among patients with severe spermatogenic failure, suggesting a concurrent Leydig cell steroidogenic dysfunction. Aromatase overexpression has been associated with increased serum and intratesticular E2 in these patients. However, it is unknown whether the sulfatase pathway contributes to the increased availability of active estrogens in patients with primary spermatogenic failure.

OBJECTIVES

To assess estrogen sulfotransferase (SULT1E1) and steroid sulfatase (STS) mRNA abundance in testicular tissue of patients with Sertoli cell-only syndrome (SCOS) and normal tissues, its association with serum and intratesticular hormone levels, and to explore the mRNA and protein testicular localization of both enzymes.

MATERIALS AND METHODS

Testicular tissues of 23 subjects with SCOS (cases) and 22 patients with obstructive azoospermia and normal spermatogenesis (controls) were obtained after biopsy. SULT1E1 and STS transcripts accumulation was quantified by RT-qPCR. For mRNA and protein localization, we performed RT-qPCR in Leydig cell clusters and seminiferous tubules isolated by laser-capture microdissection and immunofluorescence in testicular tissues. Serum and intratesticular hormones were measured by immunoradiometric assays.

RESULTS

SULT1E1 mRNA accumulation was similar in both groups. The amount of STS mRNA was higher in cases (p = 0.007) and inversely correlated with T/LH ratio (r = -0.402; p = 0.02). Also, a near significant correlation was observed with intratesticular E2 (r = 0.329, p = 0.057), in agreement with higher intratesticular E2 in cases (p < 0.001). Strong STS immunoreaction was localized in the wall of small blood vessels but not in Leydig cells. Both SULT1E1 and STS mRNA abundance was similar in Leydig cell clusters and the tubular compartment, except for lower SUTL1E1 mRNA in the seminiferous tubules of SCOS patients (p = 0.001).

CONCLUSIONS

Our results suggest that an unbalance of the STS/SULT1E1 pathway contributes to the testicular hyperestrogenic microenvironment in patients with primary spermatogenic failure and Leydig cell dysfunction.

Vasectomy and Photoperiodic Regimen Modify the Protein Profile, Hormonal Content and Antioxidant Enzymes Activity of Ram Seminal Plasma

This work aimed to determine the contribution of the testis and epididymis and the effect of the photoperiodic regimen on ram seminal plasma (SP). Semen was collected from 15 mature rams located in an equatorial (Colombian Creole and Romney Marsh, eight intact and two vasectomized) or a temperate climate (Rasa Aragonesa, three intact and two vasectomized). SP proteins were analyzed by Bradford, SDS-PAGE and difference gel electrophoresis (DIGE). Melatonin and testosterone concentrations were quantified by ELISA, and activity of glutathione peroxidase (GPx), glutathione reductase (GRD), and catalase by enzymatic assays. Vasectomy increased protein concentration and the intensity of high molecular weight bands (p < 0.001), with no differences between breeds. DIGE revealed the absence of six proteins in vasectomized rams: angiotensin-converting enzyme, lactotransferrin, phosphoglycerate kinase, sorbitol dehydrogenase, epididymal secretory glutathione peroxidase and epididymal secretory protein E1. Vasectomy also decreased melatonin concentrations in seasonal rams, and testosterone in all of them (p < 0.001), but did not affect antioxidant enzyme activity. Equatorial rams showed lower melatonin and testosterone concentration (p < 0.01) and catalase, but higher GPx activity (p < 0.05). In conclusion, vasectomy modifies the protein profile and hormonal content of ram seminal plasma, whereas the exposure to a constant photoperiod affects hormonal concentration and antioxidant enzymes activity.

Mild Exercise Rescues Steroidogenesis and Spermatogenesis in Rats Submitted to Food Withdrawal

The present investigation was undertaken to increase our insight into the molecular basis of the physiological changes in rat testis induced by food withdrawal, and to clarify whether reduced testicular function can be ameliorated by mild exercise. Male rats were selected for four separate experiments. The first of each group was chow-fed, the second was chow-fed and submitted to exercise (5 bouts in total for 30 min at 15 m/min, and 0° inclination), the third was submitted to food withdrawal (66 h) and the fourth was submitted to food withdrawal and to exercise. At the end of experiments, we investigated (i) serum and testicular sex hormone levels; (ii) protein levels of StAR, 3β-Hydroxysteroid dehydrogenase (3β-HSD) and P450 aromatase, which play a key role in steroid hormone biosynthesis; and (iii) protein levels of mitotic and meiotic markers of spermatogenesis in rats, in relation to testis morphology and morphometry. We found that mild exercise or food withdrawal alone induced a significant increase or decrease in both serum and testis testosterone levels, respectively. Interestingly, we found that these levels were brought back to basal levels when food withdrawal was combined with mild exercise. The changes in testosterone levels observed in our experimental groups correlated well with the expression of steroidogenic enzymes as well as with spermatogenic activity. With mild exercise the increased testosterone/17β-estradiol (T/E2) ratio in the testis correlated with an increased spermatogenic activity. The T/E2 ratio dropped in fasted rats and was significantly reversed when food withdrawal was combined with exercise. Histological and morphometric analyses confirmed that spermatogenic activity varied in concomitance with each experimental condition. Importantly, the testis and serum T/E2 ratios correlated, confirming that exercise rescues the decline in food withdrawal-induced spermatogenesis. In conclusion, this study highlights that mild exercise normalizes the reduced spermatogenic activity caused by food withdrawal through the modulation of the steroidogenic pathway and restoring the T/E2 ratio, underlining the beneficial effects of mild exercise on the prevention and/or amelioration of reduced testis function caused by restricted caloric intake.

Increased Gonadotropins and prolactin are linked to infertility in males

Infertility has become a significant issue among married couples worldwide. The association of variations in reproductive hormones with infertility is evaluated at a tertiary care hospital in North India. A total of 220 infertile males having infertility longer than one year (cases) and 220 age-matched fertile males with confirmed paternity in past two to three years (controls) were enrolled for the study. Serum levels of LH, FSH, testosterone and PRL were measured by Roche e411 autoanalyzer using electrochemiluminescense immunoassay technique. Significant higher levels of serum hormone (mean±SD) were found in cases vs. controls; LH (9.02±7.81 vs. 5.22±1.45 mIU/ml), FSH (11.45±14.02 vs. 4.09±1.62 mIU/ml) and PRL (199.08±80.79 vs. 127.23±81.64 µIU/ml). However, the serum testosterone level was significantly low in cases associated with male infertility (4.62±2.03 vs. 6.82±2.79 ng/ml). LH, FSH and PRL levels were significantly increased in azoospermic, oligozoospermic and asthenozoospermic infertile males while FSH and PRL were significantly elevated in normozoospermic infertile group. Conversely, mean serum testosterone levels were significantly low in all infertile subgroups in comparison to fertile controls. PRL showed a significant prediction of Normozoospermia (AUC=0.836, Z=4.916, p<0.001) in ROC analysis. Data presented here is interesting, requiring further confirmation using larger samples of multiple cohorts.

Fractionated irradiation of right thorax induces abscopal damage on testes leading to decline in fertility

Radiation-induced abscopal effect (RIAE) may influence radiotherapy efficiency. However, it is unknown whether RIAE triggers abnormal genetic consequence. We present a novel evidence that, when mice were given fractionated irradiation on right thorax, the ultrastructure of blood-testis barrier was damaged in company with apoptosis induction in testes, and the sperm number and vitality were drastically decreased so that both the fertility and the survival of their offspring were reduced. Protein microarray assay and hormone detection showed that some cytokines especially TNF-α, TGF-β and estradiol in the serum of irradiated mice increased to higher levels in consistent with abscopal damage, and this conditioned serum had toxic effect on TM4 cells in vitro. When the mice were fed with cimetidine, the above abscopal responses were significantly attenuated. This study demonstrates in the first time that the thoracic irradiation (Th-IR) induces structural and functional damage in the distal testes and further cause fertility decline of irradiated male mice, which may have important implications in the strategy development of radiotherapy in avoiding abnormal genetic consequence.

The relationships between urinary phthalate metabolites, reproductive hormones and semen parameters in men attending in vitro fertilization clinic

Evidence from previous studies has shown that phthalates may play a role in male reproductive function; however, results are still inconclusive, and the mechanism remains unclear. In this study, we first assessed whether exposure to phthalates is associated with altered reproductive hormones and semen parameters in 599 men attending an in vitro fertilization clinic. Secondly, we evaluated whether reproductive hormones could play a mediating role in the association between phthalates and sperm parameters. Eight phthalate metabolites were measured in two different spot urine samples: mono‑n‑butyl phthalate, mono-isobutyl phthalate (MiBP), monoethyl phthalate (MEP), monobenzyl phthalate, and four oxidative metabolites of di‑(2‑ethylhexyl) phthalate (DEHP) [i.e., mono‑(2‑ethylhexyl) phthalate (MEHP), mono‑(2‑ethyl‑5‑hydroxyhexyl) phthalate (MEHHP), mono‑(2‑ethyl‑5‑oxohexyl) phthalate (MEOHP), and mono‑(2‑ethyl‑5‑carboxypentyl) phthalate (MECPP)]. Semen parameters (concentration, volume, motility, and morphology) and reproductive hormones, i.e., follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone, estradiol (E₂), testosterone (TEST) and prolactin (PROL) were also determined and considered the main study outcomes. Separate multivariate linear regression was used to assess associations between levels of each urinary phthalate metabolite, molar sum of DEHP metabolites (∑DEHP), percentage of MEHP to ∑DEHP (%MEHP), and each outcome (natural log-transformed). Inverse associations were observed between TEST and MiBP (β = -0.099), FSH and MEHHP (β = -0.087), and PROL and MEOHP (β = -0.102), while a positive relationship was seen between E₂ and MEP (β = 0.098). %MEHP was associated positively with FSH (β = 0.118) and LH (β = 0.099), but negatively with TEST/LH (β = -0.086) and TEST/E₂ (β = -0.109). Sperm concentration was associated positively with MECPP (β = 0.131), MEHHP (β = 0.117), MEOHP (β = 0.107) and ∑DEHP (β = 0.111), but negatively with %MEHP (β = -0.135). All p-values were <0.05. Sobel's test indicated that FSH mediated significantly up to 60% of the positive relationship between sperm concentration and MEHHP, while FSH and LH mediated respectively 15 and 12% of the inverse association between sperm concentration and %MEHP. Further research on this topic is warranted.

The Quantitation of 7β-Hydroxy-Epiandrosterone in the Plasma and Seminal Plasma of Men With Different Degrees of Fertility

7β-hydroxy-epiandrosterone (7β-OH-EpiA) is an endogenous androgen metabolite that has been shown to exert neuroprotective, anti-inflammatory and anti-estrogenic effects. However, to the best of our knowledge no information is available about this androgen steroid in relation to sperm quality. We analyzed 7β-OH-EpiA in plasma and seminal plasma using a newly developed isotope dilution ultra-high performance liquid chromatography – mass spectrometry method. Validation met the requirements of FDA guidelines. Levels of 7β-OH-EpiA were measured in 191 men with different degrees of infertility. One-way analysis of variance followed by multiple comparison and correlation analysis adjusted for age, BMI and abstinence time were performed to evaluate the relationships between this steroid and sperm quality. Concentrations of 7β-OH-EpiA in seminal plasma were significantly higher in severely infertile men in comparison with healthy men and slightly infertile men. The same trend was found when blood plasma was evaluated. Furthermore, plasma 7β-OH-EpiA negatively correlated with sperm concentration (-0.215; p<0.01) and total count (-0.15; p<0.05). Seminal 7β-OH-EpiA was negatively associated with motility (-0.26; p<0.01), progressively motile spermatozoa (-0.233; p<0.01) and nonprogressively motile spermatozoa (-0.188; p<0.05). 7β-OH-EpiA is associated with lower sperm quality and deserves more research in that respect.

Occurrence and reproductive roles of hormones in seminal plasma

Only 2-5% of seminal fluid is composed of spermatozoa, while the rest is seminal plasma. The seminal plasma is a rich cocktail of organic and inorganic compounds including hormones, serving as a source of nutrients for sperm development and maturation, protecting them from infection and enabling them to overcome the immunological and chemical environment of the female reproductive tract. In this review, a survey of the hormones found in human seminal plasma, with particular emphasis on reproductive hormones is provided. Their participation in fertilization is discussed including their indispensable role in ovum fertilization. The origin of individual hormones found in seminal plasma is discussed, along with differences in the concentrations in seminal plasma and blood plasma. A part of review is devoted to methods of measurement, emphasising particular instances in which they differ from measurement in blood plasma. These methods include separation techniques, overcoming the matrix effect and current ways for end-point measurement, focusing on so called hyphenated techniques as a combination of chromatographic separation and mass spectrometry. Finally, the informative value of their determination as markers of male fertility disorders (impaired spermatogenesis, abnormal sperm parameters, varicocele) is discussed, along with instances where measuring their levels in seminal plasma is preferable to measurement of levels in blood plasma.

Application of testosterone supplementation in semen to improve sperm motility in asthenozoospermic males

PURPOSE

To evaluate the effect of different concentrations and durations of seminal testosterone supplementation upon the motility of sperm from asthenozoospermic males.

METHODS

Semen was collected from 41 infertile men with asthenozoospermia. After liquefaction, 200 μL was extracted from each semen sample and divided equally into five groups for a negative control, a vehicle control, and three experimental portions mixed with 4.75, 7.75, and 17.75 nmol/L of testosterone, respectively. The sperm motility was evaluated at 5, 15, 30, and 45 min following the addition of testosterone. The supernatant from remaining samples were sent for testosterone assay. Sperm viability was also evaluated after 45 min.

RESULTS

There was no difference in the number of samples in each group which showed a 20% improvement in sperm motility. Group 3 showed a significant retardation in the reduction of motility compared with Group 5 (P < 0.05). Semen samples with a final testosterone concentration of 4.51-10 nmol/L showed a significant improvement in sperm motility when measured 5 min after addition. In contrast, samples showing a rise in testosterone level above 10 nmol/L were associated with a reduction in both sperm motility and viability.

CONCLUSION

Despite sperm motility decreasing over time, supplementation of semen samples with 4.75 nmol/L of testosterone could delay such reduction. A final seminal testosterone concentration of 4.51-10 nmol/L appears to be optimal for the best sperm motility.

Disturbed testicular expression of the estrogen-metabolizing enzymes CYP1A1 and COMT in infertile men with primary spermatogenic failure: possible negative implications on Sertoli cells

Estradiol (E₂ ) is normally metabolized to hydroxyestradiols and methoxyestradiols by CYP1A1, CYP1B1 and COMT. However, an altered production of these metabolites by a disturbed expression of these enzymes is associated with reproductive and non-reproductive pathologies. In vitro studies suggest that increased hydroxyestradiols and methoxyestradiols intratesticular generation is related to male infertility, but no studies have explored whether infertile men have a disturbed testicular expression of the enzymes that generate these E₂ metabolites. The aim of this study was to assess CYP1A1, CYP1B1 and COMT testicular expression at mRNA and protein level in men with spermatogenic impairment. Seventeen men with primary spermatogenic failure (13 with Sertoli cell-only syndrome and four with maturation arrest) and nine controls with normal spermatogenesis were subjected to testicular biopsy. mRNA was quantified using real-time RT-PCR and protein expression was evaluated using western blot and immunohistochemistry followed by integrated optic density analysis. Besides, the effects of hydroxyestradiols and methoxyestradiols on testosterone-induced transcriptional activity were evaluated in TM4 cells using a luciferase reporter assay system. Our results show that patients with Sertoli cell-only syndrome had significantly elevated COMT expression at the mRNA level, higher COMT immunoreactivity in their seminiferous tubules and increased protein expression of the soluble COMT isoform (S-COMT), whereas patients with maturation arrest had significantly elevated CYP1A1 mRNA levels and higher CYP1A1 immunoreactivity in interstitial space. Finally, 2-hydroxyestradiol decreased testosterone-induced transcriptional activity in Sertoli cells in vitro. In conclusion, male infertility is related to disturbed testicular expression of the enzymes responsible for producing hydroxyestradiols and/or methoxyestradiols. If these changes are related with increased intratesticular hydroxyestradiols and methoxyestradiols concentrations, they could elicit an impaired Sertoli cell function. Our results suggest CYP1A1 and COMT as new potential targets in treating male infertility.

Effects of Elevated β-Estradiol Levels on the Functional Morphology of the Testis - New Insights

Elevated estradiol levels are correlated with male infertility. Causes of hyperestrogenism include diseases of the adrenal cortex, testis or medications affecting the hypothalamus-pituitary-gonadal axis. The aim of our study was to elucidate the effects of estradiol treatment on testicular cellular morphology and function, with reference to the treatment regimen received. Testes samples (n = 9) were obtained post-orchiectomy from male-to-female transsexuals within the age range of 26–52 years. Each patient had a minimum of 1–6 years estradiol treatment. For comparison, additional samples were obtained from microscopically unaltered testicular tissue surrounding tumors (n = 7). The tissues obtained were investigated by stereomicroscopy, histochemistry, scanning electron microscopy (SEM) and immunohistochemistry. Our studies revealed that estradiol treatment significantly decreased the diameter of the seminiferous tubules (p < 0.05) and induced fatty degeneration in the surrounding connective tissue. An increase in collagen fiber synthesis in the extracellular matrix (ECM) surrounding the seminiferous tubules was also induced. Spermatogenesis was impaired resulting in mainly spermatogonia being present. Sertoli cells revealed diminished expression of estrogen receptor alpha (ERα). Both Sertoli and Leydig cells showed morphological alterations and glycoprotein accumulations. These results demonstrate that increased estradiol levels drastically impact the human testis.

Current medical management of endocrine-related male infertility

Male factor contributes to 50%-60% of overall infertility but is solely responsible in only 20% of couples. Although most male factor infertility is ascertained from an abnormal semen analysis, other male factors can be contributory especially if the sample returns normal. Male infertility can be due to identifiable hormonal or anatomical etiologies that may be reversible or irreversible. This manuscript will highlight existing guidelines and our recommendations for hormone evaluation for male infertility and empiric therapies including multivitamins, estrogen receptor modulators (clomiphene), estrogen conversion blockers (anastrozole), and hormone replacement.

Elastography to assess the effect of varicoceles on testes: a prospective controlled study

Varicoceles are the most common and treatable cause of male infertility. The pathophysiology of varicoceles primarily includes elevated temperature, adrenal hormone reflux, gonadotoxic metabolite reflux, altered testicular blood flow, antisperm antibody formation and oxidative stress. The diagnosis of a varicocele is mainly clinical. However, a Doppler ultrasound is used to obtain clinical data and to more accurately measure testicular size. Acoustic radiation force impulse (ARFI) is an additional technique to simultaneously show different areas with different densities in a colour-coded image and a B-mode or greyscale image. This can be used for structural analysis of testicular tissue and has become an additional method for detecting pathologic tissue alterations. We enrolled 30 patients who had clinically diagnosed with left varicoceles and male infertility (Group 1). All patients were evaluated by history taking, physical examination, a spermiogram and an endocrine profile. Thirty control patients (Group 2) were randomly chosen from patients who had applied to an andrology clinic for infertility; their physical examinations and laboratory results showed normal findings. Mean elastography results were significantly different between the groups, and significantly lower in patients who had varicoceles. The relationship between hormonal profiles and elastography parameters was calculated as statistically significant negative correlations between FSH and elasticity. Additionally, a negative correlation was determined between varicocele grade and elasticity of testes. In conclusion, our prospective study showed that ARFI imaging may be more useful than palpation for determining early damage of testicular structure by varicoceles.

Oestrogens as apoptosis regulators in mammalian testis: angels or devils?

In the mammalian testis, spermatogenesis is a highly coordinated process of germ cell development, which ends with the release of ‘mature’ spermatozoa. The fine regulation of spermatogenesis is strictly dependent on sex steroid hormones, which orchestrate the cellular and molecular events underlying normal development of germ cells. Sex steroids actions also rely on the control of germ cell survival, and the programmed cell death by apoptosis has been indicated as a critical process in regulating the size and quality of the germ line. Recently, oestrogens have emerged as important regulators of germ cell fate. However, the beneficial or detrimental effects of oestrogens in spermatogenesis are controversial, with independent reports arguing for their role as cell survival factors or as apoptosis-inducers. The dual behaviour of oestrogens, shifting from ‘angels to devils’ is supported by the clinical findings of increased oestrogens levels in serum and intratesticular milieu of idiopathic infertile men. This review aims to discuss the available information concerning the role of oestrogens in the control of germ cell death and summarises the signalling mechanisms driven oestrogen-induced apoptosis. The present data represent a valuable basis for the clinical management of hyperoestrogenism-related infertility and provide a rationale for the use of oestrogen-target therapies in male infertility.

Treatment of aromatase (CYP19A1) inhibitor reduces fertility in porcine sperm

To ascertain whether aromatase (CYP19A1) expression is linked to sperm fertility of pigs, the present study determined the expression of the CYP19A1 gene in porcine sperm and its relationship with fertilization in vitro. First, to investigate its role in fertility, the presence of CYP19A1 of mRNA and protein expression in porcine sperm were confirmed by real-time (RT) or quantitative polymerase chain reaction (q-PCR) and by western blots. The expression levels were determined quantitatively using two sperm groups recovered by a Percoll gradient, which revealed that the sperm group with a low density had a higher penetration rate than that of the high-density group (P < 0.05). However, the expression level of CYP19A1 was not significantly different between the two groups. Secondly, to examine the effect of aromatase activity on fertilization, fresh semen was treated with a steroidal inhibitor, exemestane (50 μM for 0.5 h), followed by the dose- and time-dependent viability test. Our results clearly showed that an exemestane treatment effect (P < 0.05) was found for both the sperm-penetration rate and the oocyte cleavage rate. These results indicated that CYP19A1 could be involved in sperm fertility and its expression in sperm plays an important role in fertilization.

Seminal androgens, oestradiol and progesterone in oligoasthenoteratozoospermic men with varicocele

This study aimed to assess seminal androgens, oestradiol, progesterone levels in oligoasthenoteratozoospermic (OAT) men with varicocele (Vx). In all, 154 men with matched age and body mass index were investigated that were divided into healthy fertile controls (n = 35), OAT men with Vx (n = 55), OAT men without Vx (n = 64). They were subjected to assessment of semen parameters, seminal levels of testosterone (T), androstenedione (A), 5α-androstane-3 α,17 β-diol (3 α-diol), oestradiol (E2 ), 17-hydroxyprogesterone (17-OHP) and progesterone (P). Seminal levels of T and A were significantly decreased where seminal levels of 3 α-diol, E2 , 17-OHP, P were significantly higher in OAT men with/without Vx compared with fertile controls. Sperm count, sperm motility and sperm normal forms percentage demonstrated significant positive correlation with seminal T and A and significant negative correlation with seminal 3 α-diol, E2 , P. It is concluded that in fertile men, seminal T and A are significantly increased and seminal 3 α-diol, E2 , 17-OHP, P are significantly decreased compared with infertile OAT men with/without Vx. Association of Vx demonstrated a nonsignificant influence on these hormonal levels in OAT cases. Sperm count, sperm motility and sperm normal forms demonstrated significant positive correlation with seminal T, A and significant negative correlation with seminal 3 α-diol, E2 , P.

Steroid receptors and their ligands: effects on male gamete functions

In recent years a new picture of human sperm biology is emerging. It is now widely recognized that sperm contain nuclear encoded mRNA, mitochondrial encoded RNA and different transcription factors including steroid receptors, while in the past sperm were considered incapable of transcription and translation. One of the main targets of steroid hormones and their receptors is reproductive function. Expression studies on Progesterone Receptor, estrogen receptor, androgen receptor and their specific ligands, demonstrate the presence of these systems in mature spermatozoa as surface but also as nuclear conventional receptors, suggesting that both systemic and local steroid hormones, through sperm receptors, may influence male reproduction. However, the relationship between the signaling events modulated by steroid hormones and sperm fertilization potential as well as the possible involvement of the specific receptors are still controversial issues. The main line of this review highlights the current research in human sperm biology examining new molecular systems of response to the hormones as well as specific regulatory pathways controlling sperm cell fate and biological functions. Most significant studies regarding the identification of steroid receptors are reported and the mechanistic insights relative to signaling pathways, together with the change in sperm metabolism energy influenced by steroid hormones are discussed.The reviewed evidences suggest important effects of Progesterone, Estrogen and Testosterone and their receptors on spermatozoa and implicate the involvement of both systemic and local steroid action in the regulation of male fertility potential.

Clinical and laboratory profiles of a large cohort of patients with different grades of varicocele

Objective

In this retrospective study we attempted to report our own data on the different clinical parameters in association with the presence and severity of varicocele in a large group of Austrian men.

Methods

The records of 1,111 consecutive patients with clinical varicocele from 1993 to 2010 were evaluated. The presence, grade, and side of any varicocele were recorded. Semen samples, serum FSH, LH, and testosterone levels, and testicular volume were assessed.

Results

The mean age was 28.8 (±7.3) years. Three hundred seventeen (28.5%) patients presented with grade I varicocele, 427 (38.4%) with grade II varicocele, and 367 (33%) with grade III varicocele. Correlation between different grades of varicocele and semen quality indicated an over–representation of oligospermia and asthenoteratospermia in the group of grade III varicocele (p <0.05), whereas other parameters of semen quality showed no significant difference between the three groups. Serum testosterone levels and BMI were significantly associated (p <0.05) with the grade of varicocele, but no association was found with the other parameters analyzed.

Conclusions

Our analysis showed a significant relationship between the grade of varicocele and semen analysis. Moreover, higher testosterone levels and lower body mass index were associated with the higher grade of varicocele and decreased semen quality. More prospective studies are recommended.

Histological and hormonal testicular function in oligo/azoospermic infertile men

We characterised and correlated the histological and hormonal aspects of a cohort of 261 azo/oligozoospermic men, applying a quantitative/qualitative evaluation of testicular tissue and serum and intratesticular hormonal measurements. One hundred and 93 azo⁄oligozoospermic patients were diagnosed as: complete sertoli cell only syndrome (cSCOS), n = 76; focal SCOS, n = 31; maturation arrest, n = 34; hypospermatogenesis, n = 17; mixed atrophy, n = 25; and severe atrophy, n = 10. Normal spermatogenesis was observed in 68 infertile men (controls). Patients with cSCOS, focal SCOS, mixed and severe atrophy had larger LC/clusters (11.5; 11.0; 10.7; 18.9 LC/cluster) than controls (6 LC/cluster; P < 0.001). cSCOS, focal SCOS, mixed and severe atrophy patients had higher FSH, LH and lower T/LH ratio serum levels than the other groups. Intratesticular testosterone concentrations were higher in tissues with complete or focal SCOS (45.6 ng mg(-1) protein) and mixed atrophy (79.0 ng mg(-1) protein) than normal tissues (20.3 ng mg(-1) protein; P = 0.03 and P = 0.007). Considering all subjects, significant correlations were found between T/LH ratio and Leydig cells/cluster (r = 0.510, P < 0.001), FSH levels (r = -0.692, P < 0.001) and with intratesticular testosterone (r = -0.354, P = 0.001); these correlations follow the pattern of severity of spermatogenic damage. By a thorough histological evaluation, we validate the concept that the severity of spermatogenic impairment is associated with major morphological and functional disturbance of the Leydig cell compartment.

Review on autoimmune reactions in female infertility: antibodies to follicle stimulating hormone

Female fertility can be affected by diseases or dysfunctions of reproductive tract, neuroendocrine system, and immune system. Reproductive autoimmune failure can be associated with overall activation of immune system or with immune system reactions specifically directed against ovarian antigens. Majority of the antiovarian autoantibodies are directed against β-subunit of follicle stimulating hormone (anti-FSH). This paper summarizes a current clinical classification of female infertility in the context of general activation of autoimmunity and antiovarian autoimmunity by describing serum anti-FSH. The presence of naturally occurring anti-FSH in healthy women will be discussed. In addition, the putative impairment of ovarian folliculogenesis in case of increased production of those antibodies in infertile women will be characterized.

Overweight and seminal quality: a study of 794 patients

OBJECTIVES

To evaluate sperm quality, levels of markers of epididymal and accessory gland function, and T in semen from men grouped according to their body mass index (BMI).

DESIGN

Blind prospective study.

SETTING

Andrology and reproduction laboratory in Cordoba, Argentina (2006-2007).

PATIENT(S)

Seven hundred ninety-four men.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

In semen samples, sperm quality (volume, density, motility, morphology, viability, hypoosmotic swell test, and nuclear maturity) and levels of neutral alpha-glucosidase, fructose, citric acid and T.

RESULT(S)

Multivariate analysis showed a negative association between BMI and motility, rapid motility and neutral alpha-glucosidase levels, and a positive association between BMI and seminal fructose levels. No associations were found among BMI and sperm concentration, the other parameters evaluated, or seminal T levels.

CONCLUSION(S)

Results found in our study support a deleterious effect of obesity on seminal quality, probably by alterations in the function of the epididymis (i.e., in epididymal maturation).

Perfluorononanoic acid induces apoptosis involving the Fas death receptor signaling pathway in rat testis

Perfluorononanoic acid (PFNA, C9), a synthetic perfluorinated chemical containing nine carbons, accumulates and is biomagnified through food webs. This compound has been detected in the serum of humans and wildlife and has the potential for reproductive interference. Few studies, however, have reported the effects of PFNA exposure on male reproduction. To determine this, male rats were orally dosed for 1, 3 and 5mg/kgday PFNA or with vehicle for 14 days. In the present study, serum testosterone levels were decreased, while estradiol levels were increased dramatically in rats receiving 5mg PFNA/kgday. Spermatogenic cells from rats that received 5mg PFNA/kgday exhibited apoptotic features including crescent chromatin condensation and chromatin margination. Flow cytometric analysis and TUNEL assays revealed a dose-dependent increase of apoptotic cell numbers. In addition, expression of Fas and Bax mRNA levels were upregulated significantly, and Bcl-2 mRNA levels were downregulated markedly in the 3 and 5mg/kgday groups. A dose-dependent increase in levels of active caspase-8 and no significant changes of active caspase-9 were observed. Our results indicate that PFNA exposure can lead to cell apoptosis in rat testis, and this apoptosis was probably associated with the Fas death receptor-dependent apoptotic pathway.

Dietary oestrogens and male fertility potential

Reports of increased incidences of male reproductive abnormalities and falling sperm counts have prompted interest into the nature of these threats to global fertility. Xenoestrogens have been flagged as major culprits but to date, little is known about the effects of dietary phytoestrogens on male reproductive health. These non-steroidal oestrogens of plant origin are potent endocrine disruptors that modulate normal physiological functions. Phytoestrogens have become a major component in the typical Western fast food diet over the last few decades. Soy formula milk is another common source of phytoestrogens, now used increasingly as an alternative to breast or cow's milk for infants with allergies. This use is of particular concern since the most vulnerable periods for oestrogenic insult are thought to be the pre- and neonatal periods when irreversible damage can be inflicted on the developing germinal epithelium. Studies into the safety of phytoestrogens are urgently needed either to allay fears or increase awareness of the effects of our modern diet on future fertility.

Increased exposure to estrogens disturbs maturation, steroidogenesis, and cholesterol homeostasis via estrogen receptor alpha in adult mouse Leydig cells

Deteriorated male reproductive health has been connected to overexposure to estrogens or to imbalanced androgen-estrogen ratio. Transgenic male mice expressing human aromatase (AROM(+) mice) serve as an apt model for the study of the consequences of an altered androgen-estrogen ratio. Our previous studies with AROM(+) mice showed that low androgen levels together with high estrogen levels result in cryptorchidism and infertility. In the present study, the AROM(+) mice were shown to have severe abnormalities in the structure and function of Leydig cells before the appearance of spermatogenic failure. Decreased expression of adult-type Leydig cell markers (Ptgds, Vcam1, Insl3, Klk21, -24 and -27, Star, Cyp17a1, and Hsd17b3) indicated an immature developmental stage of the Leydig cells, which appears to be the first estrogen-dependent alteration. Genes involved in steroidogenesis (Star, Cyp17a1, and Hsd17b3) were suppressed despite normal LH levels. The low expression level of kallikreins 21, 24, and 27 potentially further inhibited Leydig cell function via remodeling extracellular matrix composition. In connection with disrupted steroidogenesis, Leydig cells showed enlarged mitochondria, a reduced amount of smooth endoplasmic reticulum, and an accumulation of cholesterol and precursors for cholesterol synthesis. The results of studies with AROM(+) mice crossed with estrogen receptor alpha or beta (ERalpha and ERbeta, respectively) knockout mice lead to the conclusion that the structural and functional disorders caused by estrogen exposure were mediated via ERalpha, whereas ERbeta was not involved.

Semen quality and reproductive hormones according to birthweight and body mass index in childhood and adult life: two decades of follow-up

OBJECTIVE

To investigate the association between childhood body mass index (BMI), birth weight, and adulthood BMI, and adult semen quality and level of reproductive hormones.

DESIGN

Follow-up study.

SETTING

From a pregnancy cohort established in 1984-1987.

PATIENT(S)

347 out of 5,109 sons were selected for a study conducted 2005 to 2006.

INTERVENTION(S)

Semen and blood samples were related to information on BMI in boys (5-8 years), birth weight, and adult BMI.

MAIN OUTCOME MEASURE(S)

Semen characteristics and reproductive hormones.

RESULT(S)

Neither childhood BMI, birth weight, nor adulthood BMI were significantly associated with semen quality. Men with the 33% highest childhood BMI had 15% lower sex hormone binding globulin, 8% lower testosterone, and 16% lower FSH than men with the 33% lowest childhood BMI. Men with high adulthood BMI had 14% lower testosterone, 9% lower inhibin B, 31% lower sex hormone binding globulin, and 20% higher estradiol than men with low adulthood BMI.

CONCLUSION(S)

The results do not indicate an effect of childhood BMI, birth weight, or adult BMI on semen quality, but the exposure contrast in our study was limited. The hormonal status was affected by adult BMI.

Soluble Fas and gonadal hormones in infertile men with varicocele

OBJECTIVE

To assess gonadal hormones in serum and semen as well as seminal antiapoptotic factor; soluble fibroblast associated (sFas) in infertile men associated with scrotal varicocele.

DESIGN

Prospective.

SETTING

Academic setting.

PATIENTS

Eighty-eight males: fertile healthy controls (Gr1, n = 12), fertile normozoospermia with varicocele (Gr2, n = 31), and infertile oligoasthenozoospermia with varicocele (Gr3, n = 45).

MAIN OUTCOME MEASURE(S)

Serum and seminal gonadal hormones: follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and testosterone (T), in addition to seminal sFas.

RESULTS

There were significant higher mean levels of serum FSH, serum, and seminal LH with significant lower seminal T levels in cases of Gr3 compared with Gr2. Mean seminal sFas in Gr3 were significantly higher than its levels in Gr1 and 2 (mean +/- SE 8.34 +/- 0.36 vs. 6.8 +/- 0.53 and 6.06 +/- 0.39 ng/mL, respectively). Nonsignificant differences between serum and seminal gonadal hormones were elicited between Gr2 and controls. Seminal sFas in various varicocele grades demonstrated nonsignificant differences. There were significant positive correlations between seminal sFas with serum FSH, serum LH, semen FSH, sperm abnormal forms percentage, and significant negative correlations with sperm concentration and sperm motility.

CONCLUSION(S)

sFas could play a role in germ cell apoptosis in varicocele-associated cases.