Serum levels of inhibin B in men and their relationship with gonadal hormones, testicular volume, testicular biopsy results and sperm parameters

The expression spectrum of yak epididymal epithelial cells reveals the functional diversity of caput, corpus and cauda regions

Sperm undergo a series of changes in the epididymis region before acquiring the ability to move and fertilize, and the identification of genes expressed in a region-specific manner in the epididymis provides a valuable insight into functional differences between regions. We collected epididymal tissue from three yaks and cultured epithelial cells from the caput, corpus and cauda regions of the yak epididymis using the tissue block method. RNA sequencing analysis (RNA-seq) technology was used to detect gene expression in yak epididymal caput, corpus and cauda epithelial cells. The results showed that the DEGs were highest in the caput vs. corpus comparison, and lowest in the corpus vs. cauda comparison. Six DEGs were verified by real-time fluorescence quantitative PCR (qRT-PCR), consistent with transcriptome sequencing results. The significantly enriched DNA replication pathway in the caput vs. corpus was coordinated with cell proliferation, while upregulated DEGs such as POLD1 and MCM4 were found in the DNA replication pathway. The AMPK signaling pathway was found significantly enriched in the caput vs cauda, suggesting its involvement in sperm maturation and capacitation. The TGF beta signaling pathway was screened in the corpus vs cauda and is crucial for mammalian reproductive regulation. Upregulated DEGs (TGFB3, INHBA, INHBB) are involved in the TGF beta signaling pathway. This study provides a reference for culturing yak epididymal epithelial cells in vitro, and elucidates the transcriptional profiles of epithelial cells in different segments of the epididymis, revealing the regulatory and functional differences between different segments, providing basic data for exploring the molecular mechanism of yak sperm maturation and improving the reproductive capacity of high-altitude mammals.

Behind the Genetics: The Role of Epigenetics in Infertility-Related Testicular Dysfunction

In recent decades, we have witnessed a progressive decline in male fertility. This is partly related to the increased prevalence of chronic diseases (e.g., obesity and diabetes mellitus) and risky lifestyle behaviors. These conditions alter male fertility through various non-genetic mechanisms. However, there is increasing evidence that they are also capable of causing sperm epigenetic alterations, which, in turn, can cause infertility. Furthermore, these modifications could be transmitted to offspring, altering their general and reproductive health. Therefore, these epigenetic modifications could represent one of the causes of the progressive decline in sperm count recorded in recent decades. This review focuses on highlighting epigenetic modifications at the sperm level induced by non-genetic causes of infertility. In detail, the effects on DNA methylation, histone modifications, and the expression profiles of non-coding RNAs are evaluated. Finally, a focus on the risk of transgenerational inheritance is presented. Our narrative review aims to demonstrate how certain conditions can alter gene expression, potentially leading to the transmission of anomalies to future generations. It emphasizes the importance of the early detection and treatment of reversible conditions (such as obesity and varicocele) and the modification of risky lifestyle behaviors. Addressing these issues is crucial for individual health, in preserving fertility, and in ensuring the well-being of future generations.

Seminal exosomal miR-210-3p as a potential marker of Sertoli cell damage in Varicocele

BACKGROUND

Varicocoele-associated stressors, such as hypoxia and heat, can damage cell function and viability, and some exosomal biomarkers released from impaired cells may reflect the cell status in testis.

OBJECTIVES

To find if seminal exosomal microRNAs can reflect the Sertoli cell function in varicocoele.

MATERIALS AND METHODS

Experimental left varicocoele rat model was established (n = 24), and patients with different grades of varicocoele (n = 104) were enrolled. Primary rat Sertoli cells were isolated with enzymatic hydrolysis. Exosomes were isolated from primary rat Sertoli cells, rat epididymis tissue, and human seminal plasma with polymer-based precipitation method. Exosomal microRNAs were quantified with qPCR. Inhibin-B was detected with enzyme immunoassay. The correlation analysis between microRNA and inhibin-B was evaluated with Spearman's correlation.

RESULTS

We screened 12 previously reported hypoxia-responsive microRNAs in the primary rat Sertoli cells and found that 4 exosomal microRNAs increased significantly in response to in vitro hypoxia treatment (P < .05). Of the 4 microRNAs, only miR-210-3p was upregulated in the rats with experimental varicocoele (P < .01). In the patients with varicocoele, we found that seminal exosomal miR-210-3p significantly increased in patients with grade II and III varicocoele (P < .01), and miR-210-3p negatively correlated with sperm count (P < .01) and seminal inhibin-B expression (r = -0.39, P < .01). For the 30 patients with microsurgical varicocelectomy, the operation notably decreased miR-210-3p (P < .01).

DISCUSSION AND CONCLUSION

Seminal exosomal miR-210-3p may be a novel, sensitive, and non-invasive biomarker of Sertoli cell damage in varicocoele.

Effect of Wuzi Yanzong on Reproductive Hormones and TGF-β1/Smads Signal Pathway in Rats with Oligoasthenozoospermia

Introduction

Wuzi Yanzong (WZYZ) formula, a famous traditional Chinese medicinal prescription, has been widely used to treat kidney essence insufficiency-induced oligoasthenozoospermia in ancient and modern clinical practice. Previous studies have demonstrated that WZYZ formula exhibits significantly therapeutic activity. The aim of this study was to evaluate the effect of WZYZ formula on the reproductive hormone levels and the TGF-β1/Smads signal pathway in the testis, to explore the underlying mechanisms of WZYZ formula to improve spermatogenic function of testis in rats with oligoasthenozoospermia.

Materials and Methods

In order to control the quality of the drug, the main components of the WZYZ formula were analyzed by HPLC. A rat model of oligoasthenozoospermia was established, by daily administration of tripterygium glucosides for 4 weeks, and treated with 1.62g/kg of WZYZ formula. The testes were histopathologically examined and serum levels of gonadotropin release hormone (GnRH), estradiol (E2), follicle-stimulating hormone (FSH), testosterone (T), and luteinizing hormone (LH) were measured by ELISA. TGf-β1, Smad2, and Smad4 mRNA and protein levels in the testis were evaluated by immunohistochemistry (IHC), quantitative real-time RT-PCR (qRT-PCR), and Western blotting (WB).

Result

Oral administration of WZYZ formula restored testicular structure and significantly increased the histology score in the oligoasthenozoospermic rats. In addition, WZYZ also significantly increased the serum levels of GnRH, LH, E2, and T and decreased that of FSH. Meanwhile, TGf-β1, Smad2, and Sma4 expression levels were significantly decreased.

Conclusions

WZYZ alleviates oligoasthenozoospermia by restoring the reproductive hormones and targeting the TGf-β1/Smads pathway.

Epidemiologic methods for investigating male fecundity

Fertility is a couple concept that has been measured since the beginning of demography, and male fecundity (his biological capacity to reproduce) is a component of the fertility rate. Unfortunately, we have no way of measuring the male component directly, although several indirect markers can be used. Population registers can be used to monitor the proportion of childless couples, couples who receive donor semen, trends in dizygotic twinning, and infertility diagnoses. Studies using time-to-pregnancy (TTP) may identify couple subfecundity, and TTP data will correlate with sperm quality and quantity as well as sexual activity and a number of other conditions. Having exposure data available for couples with a fecund female partner would make TTP studies of interest in identifying exposures that may affect male fecundity. Biological indicators such as sperm quality and quantity isolate the male component of fertility, and semen data therefore remain an important source of information for research. Unfortunately, often over half of those invited to provide a sperm sample will refuse, and the study is then subject to a selection that may introduce bias. Because the most important time windows for exposures that impair semen production could be early fetal life, puberty, and the time of ejaculation; longitudinal data over decades of time are required. The ongoing monitoring of semen quality and quantity should continue, and surveys monitoring fertility and waiting TTP should also be designed.

Long-term efficacy and safety of interferon-alpha-2B in patients with mumps orchitis

The aim of this study was to determine long-term efficacy and safety subcutaneous injection of interferon-alpha-2B in patients with mumps orchitis in terms of testicular volume and other testicular functions. Mumps orchitis was evaluated in 37 patients. Patients were hospitalized and administered 1 × 3,000,000 IU subcutaneous injection of interferon-alpha-2B daily for 7 days. The testicular volumes of all the patients were measured by ultrasonography in the 18th month following treatment termination. The testes volumes were evaluated by descriptive statistics as percentages. Patients were divided into three groups according to testes volumes and differences between the involved and non-involved testicles. Group I included patients with normal testes volume (> 12 ml) and a difference between testes of less than 2 ml or 20%; Group II (atrophic groups) included patients with testes volume of less than 12 ml; and Group III (hypotrophic groups) included patients with testes volume of greater than 12 ml and a difference between testes of more than 2 ml or 20%. Groups were compared in terms of results of semen analysis and serum follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels. Patients' ages ranged between 17 and 41 years (mean: 28.3 years). A total of nine atrophy cases were identified. Sixteen patients were determined to have hypotrophic testes with a difference of 2-10 ml or 20% between the involved and non-involved testicles, despite the absence of testicular atrophy. A comparison of groups revealed that sperm density, total sperm count, total motile sperm count, and motility percentage were significantly higher in Group I than in the other groups, while serum FSH and LH levels were lower in Group I than in the other groups. Although the use of interferon-alpha-2B appears to prevent testicular atrophy and protect testicular function, it leads to a considerable difference in the volume between testicles and a significant loss of testicular function. As a result, further studies are required in order to investigate the efficacy of the drug.

Pilot study of serum inhibin B as a potential marker of testosterone doping in weight lifting men

OBJECTIVE

The aim of this study was to explore effectors of the pituitary-testicular axis suitable as potential biochemical markers to screen for testosterone doping.

DESIGN

Pilot study with male bodybuilding athletes with a self-reported history of testosterone doping (repeated intramuscular administration of testosterone preparations, last injection 8 weeks or less ago) compared with an equal sized control group matched for sex, age, and body mass index.

SETTING

Endocrine outpatients.

PARTICIPANTS

Fifteen healthy young men of white background.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Inhibin B, testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH).

RESULTS

Although the levels of testosterone, LH, and FSH did not differ between the 2 groups, the serum concentrations of inhibin B in individuals with a history of testosterone doping were exclusively at or below the lower limit of the normal range for adult men (100-400 pg/mL). Inhibin B was significantly lower in those men who used testosterone for weight lifting (76.1 +/- 36.3 ng/L [mean +/- SD]) than in controls (182.1 +/- 35.4 ng/L).

CONCLUSION

A low concentration of serum inhibin B may reflect the application of exogenous testosterone and appears to be a potential marker associated with anabolic androgenic steroid doping.

Epidemiology, diagnosis, and treatment of male hypogonadotropic hypogonadism

Hypogonadotropic hypogonadism (HH), or secondary hypogonadism, is a clinical condition due to an impairment of the pituitary function, characterized by low testosterone plasma levels associated with normal or low FSH and LH plasma levels. An impairment of gonadotropin secretion and, therefore, a reduced efficiency of spermatogenesis was reported to be frequently associated to conditions different from the classical causes of secondary hypogonadism. These conditions (metabolic, endocrine and eating disorders, physical exercise etc.) have been associated with a non-classical form of HH that could be called "functional" HH (FHH). FHH differs from the classical one by the evidence that gonadotropin levels are in the low-normal range, but are inadequate for the testosterone levels, that often are also in the low-normal range. This commentary aims at reviewing knowledge on the forms of male HH in order to indicate and discuss clinical context, diagnostic and therapeutic approach in the less known non-classical form, i.e. FHH.

Increased concentrations of serum inhibin B among male workers with long-term moderate lead exposure

Lead is known to have an adverse effect to human reproductive system. This study investigates the association between different lead indices (both current and cumulative) and serum inhibin B as well as hormone concentrations in a group of 181 male lead workers. We used data collected during annual health examinations, including measurements of blood lead levels, inhibin B, follicle stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (TTE) as well as age, gender, height, weight, smoking and drinking habits. The cumulative lead index included index of cumulative blood lead (ICL) and time weighted index of cumulative blood lead (TWICL) which were calculated from the series blood lead concentrations by annual health examinations since 1991 to the time of the study. Data was analyzed by Pearson correlation and multiple regressions. We found the Pearson correlation coefficients of ICL and TWICL vs. inhibin B to be 0.220 (p=0.003) and 0.231 (p=0.008), respectively. After adjusting for age, smoking, drinking, LH, FSH, and TTE, our multiple regression models revealed that with each unit increase in ICL and TWICL, there was a 0.047 pg/mL (p=0.017) and 1.333 pg/mL (p=0.007) increase in inhibin B. We found an association between cumulative lead index and concentration of serum inhibin B in male workers exposed to lead over long period, possibly indirectly affecting spermatogenesis.

Significance of inhibin B and anti-Müllerian hormone in seminal plasma: a preliminary study

OBJECTIVE

To evaluate the predictive value of seminal inhibin B and anti-Müllerian hormone (AMH) on the outcome of testicular sperm extraction (TESE) in patients with nonobstructive azoospermia.

DESIGN

Prospective study.

SETTING

Reproductive biology department.

PATIENT(S)

Forty-seven normospermic, 28 oligozoospermic, and 68 azoospermic patients.

INTERVENTION(S)

Testicular sperm extraction.

MAIN OUTCOME MEASURE(S)

Seminal inhibin B and AMH measure.

RESULT(S)

The seminal values of inhibin B and AMH are widely dispersed. Both inhibin B and AMH seminal values are significantly different between the three groups. The average rates of seminal AMH (not inhibin B) differ significantly according to the etiology of the azoospermia. Both seminal markers are correlated. A significant positive correlation could be observed between the seminal inhibin B and the sperm count, but not for AMH. A significant correlation also exists between seminal and serum inhibin B. The predictive value for TESE outcome of each parameter is rather low. Conversely, a logistic regression combining serum FSH, seminal inhibin B, and AMH produced a satisfying area under the curve of 0.985.

CONCLUSION(S)

Seminal inhibin B and AMH values are proposed. Separately, seminal markers are poor predictors of TESE outcome. A logistic regression model led to a satisfying area under the curve of 0.985.

Serum anti-Müllerian hormone and inhibin B in disorders of spermatogenesis

This study investigates circulating concentrations of AMH and inhibin B in men with azoospermia. Serum AMH and inhibin B are significantly lower in the men with nonobstructive azoospermia compared to the controls and the men with obstructive azoospermia, suggesting that these hormones could be markers of nonobstructive azoospermia.

Serum reproductive hormone levels and sperm production in male adult rats after treatment with arresting, a fraction obtained from seminiferous tubules conditioned medium

This study used seminiferous tubule (ST) segments from adult rats to condition culture medium that had been concentrated, size fractioned and administered 10-84 days to adult rats by subcutaneous or intratesticular injection and the effects on testes weight, testosterone, luteinizing hormone (LH) and FSH levels and (homogenization-resistant) epididymal sperm count were determined. The conditioned medium obtained 2 days after culture of ST was fractionated in a 30-100 kDa component. The fraction was injected subcutaneously or intratesticularly. This factor(s), named arresting, decreases sperm count in the epididymis from 13 days to 84 days of treatment without changes in serum LH or testosterone levels. The results of the present study suggest that arresting acts on spermiogenesis/spermiation and/or the entry of sperm into the epididymis from the efferent ductules.