Inhibin B reference data for fertile and infertile men in Northeast America

Pyridaben induces mitochondrial dysfunction and leads to latent male reproductive abnormalities

As an organochloride pesticide, pyridaben (PDB) has been used on various plants, including fruiting plants and other crops. Because of emerging concerns regarding exposure to pesticides, the deleterious effects of PDB, including neuronal disease and reproductive abnormalities, have been determined. However, the intracellular mechanisms that contribute to the effects of PDB on the male reproductive system are still unknown. Therefore, we investigated the effects of PDB on the male reproductive organ, focusing on the testes using mouse testicular cells. We demonstrated that PDB suppressed cellular proliferation of mouse Leydig (TM3) and Sertoli (TM4) cells. Additionally, PDB disturbed calcium homeostasis via mitochondrial dysfunction and activation of endoplasmic reticulum stress. Furthermore, PDB inhibited transcriptional gene expression regarding the cell cycle, as well as steroidogenesis and spermatogenesis, which are the primary functions of TM3 and TM4 cells. Moreover, we verified via western blot analysis that PDB dysregulated the intracellular cell signaling pathways in mitochondrial-associated membranes and the Mapk/Pi3k pathway. Lastly, we confirmed that PDB efficiently suppressed the spheroid formation of TM3 and TM4 cells mimicking an in vivo environment. Collectively, the current results indicate that PDB induces testicular toxicity and male reproductive abnormalities by inducing mitochondrial dysfunction, endoplasmic reticulum stress and calcium imbalance.

Bifenthrin impairs the functions of Leydig and Sertoli cells in mice via mitochondrion-endoplasmic reticulum dysregulation

Bifenthrin (BF) is a synthetic insecticide that is widely used in fields, resulting in an increase in its exposure to animals. However, reports on the toxic effects of BF on mammalian species and the underlying mechanism are still lacking. Here, we elucidated the mechanism underlying the toxic effects of BF on mouse reproduction using cell lines of immature mouse Leydig (TM3) and Sertoli (TM4) cells, which are constituent cells of testes. Our results show that BF suppressed the proliferation and viability of TM3 and TM4 cells. Additionally, treatment with BF induced cell cycle arrest, apoptotic cell death, and DNA fragmentation. Mitochondrial dysfunction and disruption of calcium homeostasis were observed in BF-treated TM3 and TM4 cells. Further, bifenthrin modulated unfolded protein response and mitochondrion-associated membrane and mitogen-activated protein kinase (MAPK)/phosphoinositide 3-kinase (PI3K) signaling pathways. The expression of the mRNAs related to cell cycle progression, steroidogenesis, and spermatogenesis was downregulated by BF, suggestive of testicular toxicity. Taken together, these results demonstrate the intracellular mechanism of action of BF to involve antiproliferative and apoptotic effects and testicular dysfunction in mouse testis.

Impact on testicular function of a single ablative activity of 3.7 GBq radioactive iodine for differentiated thyroid carcinoma

STUDY QUESTION

What are the consequences of radioactive iodine (RAI) therapy for testicular function?

SUMMARY ANSWER

A single activity of 3.7 GBq RAI for differentiated thyroid carcinoma (DTC) treatment in young men transiently altered Sertoli cell function and induced sperm chromosomal abnormalities.

WHAT IS KNOWN ALREADY

Few studies, mainly retrospective, have reported the potential impacts of RAI on endocrine and exocrine testicular function.

STUDY DESIGN, SIZE, DURATION

A longitudinal prospective multi-center study on testicular function performed in DTC patients before a single 131I ablative activity of 3.7 GBq (V0) and at 3 months (V3) and 13 months (V13) after treatment.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Forty male patients, aged 18-55 years, with DTC participated. Hormonal analysis included FSH, LH, testosterone and inhibin B serum levels at V0, V3 and V13. Furthermore, sperm parameters, DNA fragmentation and sperm chromosomal abnormalities were evaluated at each time points. The differences in all parameters, between V0-V3, V0-V13 and V3-V13, were analyzed, using a Wilcoxon test.

MAIN RESULTS AND THE ROLE OF CHANCE

Prior to RAI administration, all patients had normal gonadal function. At V3, a statistically significant increase in FSH levels and a decrease in inhibin B levels were observed and sperm concentration, as well as the percentage of morphologically normal spermatozoa, were significantly decreased (P < 0.0001). These modifications were transient as both sperm concentration and normal morphology rate returned to baseline values at V13. However, at this later time point, FSH and inhibin B levels were still impacted by RAI administration but remained in the normal range. Although no DNA fragmentation was observed at V3 nor V13, our study revealed a statistically significant increase in the number of sperm chromosomal abnormalities both at V3 (P < 0.001) and V13 (P = 0.01).

LIMITATIONS, REASONS FOR CAUTION

Among the 40 patients included in the study, only 24 had all the parameters available at all visits.

WIDER IMPLICATIONS OF THE FINDINGS

Prospective studies with longer term follow up would be helpful to determine whether the chromosome abnormalities persist. These studies would be required before sperm banking should be suggested for all patients. However, sperm preservation for DTC patients who require cumulative radioiodine activities higher than 3.7 GBq should be proposed.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Programme Hospitalier de Recherche Clinique, AP-HP (No. P040419). The authors report no conflict of interest in this work.

TRIAL REGISTRATION NUMBER

NCT01150318.

Comparison of Serum Inhibin B and Follicle-Stimulating Hormone (FSH) Level between Normal and Infertile Men in Yaoundé

Objective

Hormones play a vital role in initiating and maintaining male reproductive function. The present study explores the influence and predictive ability of two reproductive hormones on semen quality among men who were partners in an infertile couple.

Design

During our cross sectional study, men were recruited from private and public hospital and laboratories for clinical evaluation of fertility status.

Methods

Fresh semen samples were assessed for quality (concentration, motility and morphology) according to the 2010 World Health Organization manual and the serum levels of hormones, including follicle-stimulating hormone (FSH), Inhibin B was measured (ELISA).

Results

We found a significant difference in the two groups regarding sperm concentration (p < 0.0001), total sperm count (p < 0.0001), total sperm count (p < 0.0001), total sperm count (p < 0.0001), total sperm count (p < 0.0001), total sperm count (

Conclusion

Consistent with other studies, our results show strong association between semen quality and FSH and Inhibin B.

Low-dose exposure to bisphenols A, F and S of human primary adipocyte impacts coding and non-coding RNA profiles

Bisphenol A (BPA) exposure has been suspected to be associated with deleterious effects on health including obesity and metabolically-linked diseases. Although bisphenols F (BPF) and S (BPS) are BPA structural analogs commonly used in many marketed products as a replacement for BPA, only sparse toxicological data are available yet. Our objective was to comprehensively characterize bisphenols gene targets in a human primary adipocyte model, in order to determine whether they may induce cellular dysfunction, using chronic exposure at two concentrations: a “low-dose” similar to the dose usually encountered in human biological fluids and a higher dose. Therefore, BPA, BPF and BPS have been added at 10 nM or 10 μM during the differentiation of human primary adipocytes from subcutaneous fat of three non-diabetic Caucasian female patients. Gene expression (mRNA/lncRNA) arrays and microRNA arrays, have been used to assess coding and non-coding RNA changes. We detected significantly deregulated mRNA/lncRNA and miRNA at low and high doses. Enrichment in “cancer” and “organismal injury and abnormalities” related pathways was found in response to the three products. Some long intergenic non-coding RNAs and small nucleolar RNAs were differentially expressed suggesting that bisphenols may also activate multiple cellular processes and epigenetic modifications. The analysis of upstream regulators of deregulated genes highlighted hormones or hormone-like chemicals suggesting that BPS and BPF can be suspected to interfere, just like BPA, with hormonal regulation and have to be considered as endocrine disruptors. All these results suggest that as BPA, its substitutes BPS and BPF should be used with the same restrictions.

Active immunization with GnRH-tandem-dimer peptide in young male rats reduces serum reproductive hormone concentrations, testicular development and spermatogenesis

GnRH sterilization vaccines have been developed for various practical and clinical reasons. However, conjugation of GnRH peptide to carrier protein has many drawbacks, hampering the further commercialization of GnRH vaccines. In this study, a new nonconjugated GnRH vaccine, D-Lys6-GnRH-tandem-dimer peptide (TDK), emulsified in Specol adjuvant was investigated for its immunocastration efficacy in young male rats. Prepubertal male rats were randomly allocated into three groups (n = 12): control (no treatment), surgically castrated or immunized against 100 μg TDK in Specol adjuvant at 6 weeks of age (with a booster 8 weeks later). Blood samples (for antibody titers and hormone concentrations) were collected at 2-week intervals until rats were killed (18 weeks of age). Compared to intact controls, active immunization against TDK reduced (P < 0.05) serum concentrations of testosterone, inhibin B, LH and FSH, prevented the onset of spermatogenesis at puberty. Furthermore, mRNA expressions of GnRH receptor, LH-β and FSH-β in the pituitary, LH receptor, FSH receptor, inhibin α, βA and βB subunit in the testes were decreased in immunocastrated rats compared to intact controls (P < 0.05). These results demonstrate for the first time that GnRH-tandem-dimer peptide emulsified in Specol is a promising veterinary sterilization medicine.

The serum inhibin B concentration and reference ranges in normozoospermia

OBJECTIVE

Although an inhibin B assay may be useful in the assessment of testicular function in a number of genital conditions, reliable reference ranges are still lacking. The present study sought to establish the reference range for serum inhibin B by applying the updated Gen II assay.

DESIGN

This prospective study included 818 men referred for semen analysis: 377 were normozoospermic (reference group) and 441 presented at least one abnormal semen parameter (case group).

METHODS

Semen parameters were interpreted according to the 2010 World Health Organization manual and David's modified classification for normal morphology. The inhibin B concentration was determined with the current ELISA.

RESULTS

In the reference group, the 2.5th percentile for inhibin B was 92 pg/ml and the 97.5th percentile for FSH was 7.8 IU/l. In the overall population, an inhibin B level <92 pg/ml was associated with increased odds ratio (OR; 95% CI) for oligozoospermia (16.93 (9.82-29.18), P<0.0001), asthenozoospermia (4.87 (2.88-8.10), P<0.0001), and teratozoospermia (2.20 (1.31-3.68), P=0.0026). The combination of a FSH >7.8 IU/l and an inhibin B <92 pg/ml was associated with greater OR for oligozoospermia (98.74 (23.99-406.35), P<0.0001) than for each hormone considered separately.

CONCLUSIONS

A new reference range for serum inhibin B was established by the use of updated immunoassay. The correlations between hormone levels and semen parameters highlighted the importance of establishing these values with respect to the spermogram. When combined with FSH assay, the inhibin B range may be of value in the evaluation of spermatogenesis in a number of male genital conditions.

A prospective study in male recipients of kidney transplantation reveals divergent patterns for inhibin B and testosterone secretions

Background

Male patients with chronic kidney disease often exhibit the biological and clinical hallmarks of an abnormal hypothalamo–pituitary–gonadal axis. It is known that dialysis does not reverse this impaired endocrine status; however, the impact of kidney transplantation (KT) is still controversial. The aim of our study was to investigate the levels of serum gonadotropins, testosterone, and inhibin B during dialysis and after KT.

Methods

A longitudinal and prospective single center study was led in an academic setting. Blood hormones levels were assayed by immunoassays in 53 men (mean age: 37 years) receiving dialysis (T₀) and at 6 months post-KT (T₁₈₀). These data were compared with those from 46 fertile semen donors (mean age: 37 years). The main outcome measure was the between-groups differences in hormones levels. A second criterion was the comparison of T₀ and T₁₈₀ hormones levels according to the immunosuppressive regimen.

Results

For patients ongoing dialysis, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) mean levels were high, whereas testosterone and inhibin B mean levels remained normal. After KT, LH levels returned to normal whereas FSH was significantly increased. Testosterone levels remained normal whereas inhibin B levels significantly decreased. We found that the combination tacrolimus plus mycophenolic acid significantly decreased post-KT inhibin B levels. Moreover, we found that pre-graft inhibin-B level was independent of testosterone and could predict low post-operative inhibin B level with a sensitivity of 77% and a specificity of 92%.

Conclusions

Our study suggests that endocrine secretions of Leydig and Sertoli cells are differently impacted by dialysis, KT and immunosuppressive regimen raising new issues to explore.

Sperm counts and endocrinological markers of spermatogenesis in long-term survivors of testicular cancer

Background:

The objective of this study was to assess markers of spermatogenesis in long-term survivors of testicular cancer (TC) according to treatment, and to explore correlations between the markers and associations with achieved paternity following TC treatment.

Methods:

In 1191 TC survivors diagnosed between 1980 and 1994, serum-follicle stimulating hormone (s-FSH; n=1191), s-inhibin B (n=441), and sperm counts (millions per ml; n=342) were analysed in a national follow-up study in 1998–2002. Paternity was assessed by a questionnaire.

Results:

At median 11 years follow-up, 44% had oligo- (<15 millions per ml; 29%) or azoospermia (15%). Sperm counts and s-inhibin B were significantly lower and s-FSH was higher after chemotherapy, but not after radiotherapy (RT), when compared with surgery only. All measures were significantly more abnormal following high doses of chemotherapy (cisplatin (Cis)>850 mg, absolute cumulative dose) compared with lower doses (Cis ⩽850 mg). Sperm counts were moderately correlated with s-FSH (−0.500), s-inhibin B (0.455), and s-inhibin B : FSH ratio (−0.524; all P<0.001). All markers differed significantly between those who had achieved post-treatment fatherhood and those with unsuccessful attempts.

Conclusion:

The RT had no long-term effects on the assessed markers of spermatogenesis, whereas chemotherapy had. At present, the routine evaluation of s-inhibin B adds little in the initial fertility evaluation of TC survivors.

Expansion and de novo occurrence of Y chromosome microdeletions occurring via natural vertical transmission in northeastern China

OBJECTIVE

To determine characteristics of classical and partial deletions of the Y chromosome azoospermia factor (AZF) region transmitted from father to son by natural fertilization.

METHODS

Patients from northeastern China with primary male infertility (n = 10) and their fathers were investigated. Healthy fertile men and women were recruited as positive and negative controls, respectively. The Y chromosome microdeletions were detected by polymerase chain reaction. Serum concentrations of reproductive hormones were determined by electrochemiluminescence immunoassay and enzyme-linked immunosorbent assay.

RESULTS

Expansions of microdeletions were observed in seven father–son pairs; de novo microdeletions were found in the remaining three father–son pairs. The Y chromosome microdeletions were larger in sons than in their fathers. Patients with infertility had significantly higher levels of follicle stimulating hormone and lower levels of inhibin B than fertile men.

CONCLUSIONS

The Y chromosome microdeletions were transmitted from father to son via natural transmission. These microdeletions may expand during transmission or arise de novo, possibly resulting in reduced fertility.

Diagnostic applications for inhibin and activins

Inhibin and activins play major roles as paracrine and autocrine signaling molecules in reproduction and development where the main emphasis has been placed in developing potential diagnostic applications. While a role for activin assays in diagnostics has so far been unfounded, ELISAs specific for the biologically active inhibin A and B dimers, and for free inhibin alpha subunits, alone or in combination have found some specific diagnostic applications. Addition of inhibin A to the triple test for Down syndrome in the second trimester of pregnancy, measurement of total inhibin as a marker of certain forms of ovarian cancer in specific circumstances, and inhibin B for male fertility are useful diagnostics. A review of the evidence so far suggests that other applications for inhibin and activin assays have yet to be confirmed, or translated into reliable tools for clinical practice.

Male infertility in Northeast China: a cytogenetic study of 135 patients with non-obstructive azoospermia and severe oligozoospermia

PURPOSES

To detect the frequency and types of chromosomal anomalies with non-obstructive azoospermia and severe oligozoospermia in Northeast China, and to compare the frequencies with other regions of China and the world. To investigate the general characteristics of this population.

METHODS

Eighty-one men with non-obstructive azoospermia and 54 men with severe oligozoospermia were recruited. Karyotype analyses were performed on peripheral blood lymphocytes using standard G-banding. Measurements of follicle-stimulating hormone, testosterone, prolactin, and inhibin B were obtained.

RESULTS

The frequency of chromosomal anomalies for patients with non-obstructive azoospermia (17.28%) was comparable with studies from Europe, Africa, Asia, and other regions of China. However, the frequency for patients with severe oligozoospermia (9.26%) was slightly higher than reported from other Asian countries. The infertile men were more likely than the fertile to smoke and consume alcohol, and to have significantly lower levels of inhibin B.

CONCLUSIONS

For infertile men in Northeast China, chromosome analysis is a necessary part of routine genetic testing, and the contributing effects of high smoking and alcohol consumption rates of this population should be discussed during genetic counseling.

Alterations in the spermatic function generated by obesity in rats

In order to assess the effect of obesity on epididymal and germinal epithelia in control rats and obese rats induced by a high fat diet, we evaluated the epididymal and testicular morphologies, lipid peroxidation in the epididymis, leptin serum levels, steroid hormones, insulin, cholesterol, triglycerides, glycemia and some spermatobioscopic parameters. No significant difference was observed in the levels of insulin, glucose, cholesterol and triglycerides between the two groups. Nonetheless, in the obese rats, circulating leptin and estradiol levels showed a significant increase and there was a decline in the testosterone levels. The same group showed an increase in the lipid peroxidation of the epididymis and reduced spermatobioscopic parameters. The heads of the epididymis showed morphological differences in obese rats. No significant difference was observed between the testes of both groups. There is a clear evidence of an effect on sperm in obese rats and this seems to occur in the epididymis.

Inhibin B and anti-Müllerian hormone in spermatic vein of subfertile men with varicocele

INTRODUCTION

The pathophysiology of subfertility in men with varicocele remains unclear as well as the role of inhibin B (Inh-B) and anti-Müllerian hormone (AMH). The aim of this study was to evaluate Inh-B and AMH concentrations in the spermatic vein of subfertile men with varicocele.

PATIENTS AND METHODS

A total of 61 subfertile men with varicocele and 31 fertile controls underwent standard andrological evaluation. All subfertile men underwent varicocelectomy, during which blood samples were obtained from the spermatic vein to evaluate Inh-B and AMH concentrations.

RESULTS

Peripheral vein Inh-B concentrations in men with varicocele were lower as compared to controls (52.9 [8.3-136.0) vs 116±9.7 ng/dL, P = .001). There was no difference in AMH concentrations (10.2 [4.4-45.4]) vs 10.4±0.8 pg/dL, P = 0.9). Spermatic vein Inh-B concentrations in men with varicocele were higher compared to those of peripheral vein (87.6±4.4 vs 52.9 [8.3-136.0] ng/dL, P = .001). On the contrary, spermatic vein AMH concentrations were lower compared to those from peripheral vein (8.84 [3.9-47.7] vs 10.2 [4.4-45.4] pg/dL, P = .013).

CONCLUSIONS

Inh-B constitutes a reliable marker of Sertoli cell function as well as spermatogenesis. On the contrary, the clinical significance of AMH in men with varicocele remains to be elucidated.