Short-term FSH treatment and sperm maturation: a prospective study in idiopathic infertile men

Phoenix dactylifera L. pollen versus pentoxifylline on improvement of sperm parameters in idiopathic male infertility: A randomized clinical trial

ETHNOPHARMACOLOGICAL RELEVANCE

Phoenix dactylifera L. pollen is the male reproductive dust of palm flowers known as a natural product that is considered a strong stimulant of sexual potency and fertility in Iranian traditional medicine (ITM). In this regard, no evidence-based medications are empirically prescribed to treat IMI. However, applying traditional medicine for the treatment of male infertility has attracted more attention in recent years.

AIM OF THE STUDY

Phoenix dactylifera L. pollen was compared with pentoxifylline (PTX) to evaluate its efficacy on sperm parameters.

MATERIALS AND METHODS

During this parallel randomized controlled trial, 80 adult men with asthenozoospermia, oligozoospermia, or teratozoospermia (age 20-35 years) were enrolled. In two separate groups of participants with a 1:1 ratio, participants received either 6 g of Phoenix dactylifera L. pollen powder daily or 400 mg of PTX tablets daily for 90 days. We measured the sperm parameters as well as the serum sex hormones in the sample. ANCOVA and t-tests were used to compare groups.

RESULTS

There was no significant difference between the study groups in terms of baseline characteristics or demographic characteristics. According to the results, participants who took Phoenix dactylifera L. pollen powder had significantly improved sperm concentration (p = 0.016), morphology (p = 0.029), sperm counts (p = 0.012), progressive motility (p = 0.016), total motility (p = 0.018), and reduced immotile sperms (p = 0.014) compared to those who took PTX.

CONCLUSIONS

In light of these results, Phoenix dactylifera L. pollen is recommended as a treatment factor for ameliorating IMI by enhancing sperm functional capacity and semen parameters.

Frequency, morbidity and equity - the case for increased research on male fertility

Currently, most men with infertility cannot be given an aetiology, which reflects a lack of knowledge around gamete production and how it is affected by genetics and the environment. A failure to recognize the burden of male infertility and its potential as a biomarker for systemic illness exists. The absence of such knowledge results in patients generally being treated as a uniform group, for whom the strategy is to bypass the causality using medically assisted reproduction (MAR) techniques. In doing so, opportunities to prevent co-morbidity are missed and the burden of MAR is shifted to the woman. To advance understanding of men's reproductive health, longitudinal and multi-national centres for data and sample collection are essential. Such programmes must enable an integrated view of the consequences of genetics, epigenetics and environmental factors on fertility and offspring health. Definition and possible amelioration of the consequences of MAR for conceived children are needed. Inherent in this statement is the necessity to promote fertility restoration and/or use the least invasive MAR strategy available. To achieve this aim, protocols must be rigorously tested and the move towards personalized medicine encouraged. Equally, education of the public, governments and clinicians on the frequency and consequences of infertility is needed. Health options, including male contraceptives, must be expanded, and the opportunities encompassed in such investment understood. The pressing questions related to male reproductive health, spanning the spectrum of andrology are identified in the Expert Recommendation.

Predictive role of 17α-hydroxy-progesterone serum levels of response to follicle-stimulating hormone in patients with abnormal sperm parameters

OBJECTIVES

To study the possible role of serum 17α-hydroxy-progesterone (17αOH-P) levels in predicting favorable responses to follicle-stimulating hormone (FSH) administration in patients with normal serum FSH levels and idiopathic abnormal sperm parameters.

DESIGN

Prospective cohort study.

SETTING

University-affiliated fertility center.

PATIENTS

Fifty patients with oligozoospermia, asthenozoospermia, and/or teratozoospermia and normal serum levels of gonadotropins and total testosterone (TT).

INTERVENTION

Treatment with exogenous FSH is administered subcutaneously at a dose of 150 IU 3 times a week for 3 consecutive months.

MAIN OUTCOME MEASURE(S)

Luteinizing hormone levels, FSH levels, TT levels, 17αOH-P levels, testicular volume, conventional sperm parameters, and seminal spermatid concentration were evaluated before and after therapy. To evaluate the predictive role of pretreatment serum 17αOH-P levels on FSH responsiveness, the doubling of sperm concentration at the end of the FSH administration was considered a positive outcome.

RESULTS

After therapy, patients showed a significant increase in sperm concentration, total sperm count (TSC), progressive motility, percentage of normal forms, FSH levels, TT levels, and testicular volume. There was a negative correlation between pretreatment 17αOH-P levels and the posttreatment increase in sperm concentration, TSC, progressive motility, and normal morphology, and a positive correlation with the posttreatment increase in spermatids. Predictive analysis showed that 17αOH-P levels (<1.18 ng/mL) foretold a doubling of sperm concentration with a sensitivity of 90.0% and a specificity of 73.3%, and of TSC with a sensitivity of 91.3% and a specificity of 81.48%.

CONCLUSION

The results of this study suggest that pretreatment serum levels of 17αOH-P, a marker of steroidogenic function, appear to be able to predict the success of subcutaneous administration of exogenous FSH in terms of spermatogenesis improvement. Receiver operating characteristic curves indicated that 17αOH-P levels (<1.18 ng/mL) predict a doubling of sperm concentration and TSC after exogenous FSH administration to patients with idiopathic abnormal sperm parameters and normal gonadotropin levels.

Spontaneous alterations in semen parameters are associated with age, accessory gland function and the FSHB c.-211G>T variant

BACKGROUND

There is a strong within-subject alteration of semen parameters in men with infertility. However, it remains unknown in which subgroup variations are likely to occur and which semen parameters are affected.

OBJECTIVE

To evaluate parameters associated with spontaneous alterations in semen analysis.

PATIENTS AND METHODS

We retrospectively selected 3456 men with infertility without known causes affecting spermatogenesis or sperm output for analysis of repeated ejaculate samples. Exclusion criteria comprised sperm concentration <1 million/mL, abnormal follicle-stimulating hormone or low testosterone, and low bitesticular volume (<10 mL). Grouped linear two-level nested mixed-effect models were applied. The analyzed parameters included abstinence time, bitesticular volume, age, accessory gland markers, follicle-stimulating hormone, and FSHB c.-211 variants.

RESULTS

Groups include A (n = 397): ≥1.0 to <5.0 million/mL, B (n = 708): ≥5.0 to <15.0 million/mL, and C (n = 2351): ≥15.0 million/mL. Groups A, B, and C: changes in ejaculate volume were associated with alterations in total sperm count and motility (p < 0.003). Changes were, controlled for abstinence time (p < 0.001), related to α-glucosidase, fructose, or zinc (p = 0.005-0.02). Group A + B: fluctuations in follicle-stimulating hormone level influenced sperm concentration/count (p = 0.004-0.02), albeit only in men with FSHB c.-211 GG (p = 0.007-0.02). T-allele carriers did not show changes in follicle-stimulating hormone levels (p > 0.1). Group B: age <50 years (p = 0.007-0.01) and normal bitesticular volume (p = 0.008-0.02) were associated with spontaneous increases in sperm concentration, count, and motility.

CONCLUSION

Semen parameters exhibit intra-individual alterations associated with organic, hormonal, and genetic variables. Changes are pronounced in younger men with normal bitesticular volume and oligozoospermia to almost normozoospermia. The effect is modulated by abstinence time, accessory gland function, and fluctuations in follicle-stimulating hormone level, which is bound to FSHB c.-211G>T variant. Judgment of semen analysis should be based on two semen samples, with abstinence times between 4 and 5 days. As a future perspective, it might be investigated whether younger men with normal bitesticular volume who are unable to elicit increases in serum follicle-stimulating hormone (FSHB c.-211 genotype of GT/TT) benefit from improving accessory gland function and increasing follicle-stimulating hormone.

Investigational follicle-stimulating hormone receptor agonists for male infertility therapy

INTRODUCTION

According to estimates by the World Health Organization, about 17.5% of the adult population - roughly 1 in 6 globally - experience infertility. The causes of male infertility remain poorly understood and have yet to be fully evaluated. Follicle-stimulating hormone (FSH) represents an available and useful therapeutic strategy for the treatment of idiopathic infertility.

AREAS COVERED

We provide here an overview of the molecular mechanisms by which FSH stimulates Sertoli cells and the schemes, dosages, and formulations of FSH most prescribed so far and reported in the literature. We also evaluated the possible predictor factors of the response to FSH administration and the indications of the latest guidelines on the use of FSH for the treatment of male infertility.

EXPERT OPINION

FSH therapy should be considered for infertile male patients with oligoasthenoteratozoospermia and normal serum FSH levels to quantitatively and qualitatively improve sperm parameters and pregnancy and birth rates. The grade of evidence is very low to low, due to the limited number of randomized controlled studies and patients available, the heterogeneity of the studies, and the limited effect size. To overcome these limitations, preclinical and clinical research is needed to evaluate the most effective dose and duration of FSH administration.

The role of male hypogonadism, aging, and chronic diseases in characterizing adult and elderly men with erectile dysfunction: a cross-sectional study

BACKGROUND

Erectile function depends on a complex interaction between demographic, metabolic, vascular, hormonal, and psychological factors that trigger erectile dysfunction (ED). In the present study we carried out a cross-sectional study assessing the impact of non-communicable chronic diseases (NCDs), male hypogonadism, and demographic factors in characterizing men with ED. Four hundred thirty-three consecutive outpatients with ED were extracted from the electronic database from January 2017 to December 2019. The International Index of Erectile Function (IIEF) 5 score was used to diagnose ED and stratify its severity, standardized values of serum testosterone (10.5 nM/L) and luteinizing hormone (LH 9.4 IU/L) to diagnose and classify male hypogonadism and the Charlson Comorbidity Index (CCI) to weigh the role of each NCD on ED.

RESULTS

Forty-six percent of participants were eugonadal (EuG), 13% had organic hypogonadism (OrH), and the remaining 41% had functional hypogonadism (FuH). Hypogonadal men had a significantly lower IIEF 5 score (p < .0001) than EuG. FuH had a higher CCI than OrH and EuG (all p < .0001). In a multivariable model, only free T (FT) and Sex Hormone Binding Globulin (SHBG) showed a direct correlation with the IIEF 5 score (all p < .0001). Age and CCI had an inverse correlation with IIEF 5 score (all p < .0001).

CONCLUSION

Serum FT, SHBG, and CCI are the leading determinants of ED severity. Besides overt hypogonadism, a relevant burden of severe NTCDs in middle-aged or older adults features the patient's characteristics who will suffer from severe ED. Appropriate clinical approaches and, when necessary, treatments are required in these clusters of patients.

Diagnostic and therapeutic workup of male infertility: results from a Delphi consensus panel

Male factor infertility (MFI) is a rising issue worldwide with significant socioeconomic costs and negative psychological consequences for the couple. Current guidelines provide recommendations for its diagnosis and treatment but several gaps in the management of MFI are encountered in clinical practice due to the lack of available evidence in published literature. Uncertainty in the management of MFI cases leads to a high degree of variability in therapeutic approaches. We planned a Delphi consensus method to provide insights and help bridge the gaps that separate clinical guidelines from real-world practice. The Advisory Board collected 41 statements on debated topics in the management of MFI, each including multiple items designed as a 5-point Likert scale. The questionnaire was sent by e-mail to a panel of Italian experts for a first round of voting; members of the panel were later invited to a second round of voting, preceded by discussion of the "hot topics" identified in the first round. At both rounds of the Delphi consensus 68 experts participated to the voting process. After the first round 25 statements were identified as hot topics, and these underwent the second round of voting. Consensus was reached on many, but not all cases, leaving vagueness on few debated topics where decisions are unsupported by clinical studies or driven by controversial results. In conclusion, indications emerging from this large panel of experts may help guide the management of male factor infertility in clinical practice. Studies are needed to address unanswered questions left by cases for whom no consensus was reached.

Changes in histology, protein expression, and autophagy in dairy goat testes during nonbreeding season†

Seasonal reproduction contributes to increased chances of offspring survival in some animals. Dairy goats are seasonal breeding mammals. In this study, adult male Guanzhong dairy goats (10-12 months old) were used. Testis size, semen quality, hormone level, apoptosis of germ cells, and autophagy of Sertoli cells were analyzed in dairy goats during the breeding (October) and nonbreeding (April) seasons. We found that, during the nonbreeding season for dairy goats, semen quality, follicle-stimulating hormone (FSH) levels, and testosterone levels were reduced, and the number of apoptotic germ cells increased. The proliferation with decrease activity of germ cells in dairy goat during the nonbreeding season was significantly affected. However, the testis size did not change seasonally. Interestingly, Sertoli cell autophagy was more active during the nonbreeding season. The expression levels of FSH receptor, wilms tumor 1, androgen binding protein, glial cell derived neurotrophic factor, and stem cell factor decreased in dairy goats during the nonbreeding season. In summary, our results indicate that spermatogenesis in dairy goats during the nonbreeding season was not completely arrested. In addition, germ cell apoptosis and the morphology of Sertoli cells considerably changed in dairy goats during the nonbreeding season. Sertoli cell autophagy is involved in the seasonal regulation of spermatogenesis in dairy goats. These findings provide key insights into the fertility and spermatogenesis of seasonal breeding animals.

FSH dosage effect on conventional sperm parameters: a meta-analysis of randomized controlled studies

Follicle-stimulating hormone (FSH) represents a therapeutic option in normogonadotropic patients with idiopathic oligozoospermia. The aim of this review was to evaluate the possible dose- and drug-dependent efficacy of FSH treatment on conventional sperm parameters. We performed a comprehensive systematic review via a meta-analysis of all available randomized controlled trials, in which FSH administration was compared with placebo or no treatment when administered to normogonadotropic patients with idiopathic oligozoospermia. Of the 971 articles that were retrieved, 5 were finally included, including a total of 372 patients and 294 controls. Overall, FSH treatment was effective in ameliorating the sperm concentration, total count, progressive motility, but not normal forms. On the basis of the weekly dosage, the studies were classified into those using low (175–262.5 IU per week), intermediate (350–525 IU per week), and high (700–1050 IU per week) doses. At low doses, FSH improved only sperm motility. At intermediate doses, FSH ameliorated sperm concentration and morphology. Total sperm count and progressive motility showed a trend toward the increase. At high doses, FSH increased sperm concentration, total sperm count, and progressive motility. Sperm morphology showed a trend toward the increase. Finally, both highly purified FSH (hpFSH) and recombinant human FSH (rhFSH) improved sperm concentration, total sperm count, progressive motility, but not morphology. No different efficacy was observed between these two preparations. This meta-analysis provides evidence in favor of high FSH doses. The FSH efficacy was not related to the preparation type (recombinant vs highly purified). Further studies are needed to evaluate the effectiveness of long-standing treatment regimes.

Central role of ultrasound in the evaluation of testicular function and genital tract obstruction in infertile males

BACKGROUND

Scrotal color Doppler ultrasonography and transrectal ultrasonography provide crucial information about the clinical status of testes and male accessory glands.

OBJECTIVE

To analyze the impact of ultrasound in the evaluation of infertile males.

MATERIALS AND METHODS

A total of 1120 records from infertile men were retrospectively evaluated (from January 2016 up to June 2020). Data on physical examination, semen analysis, sperm culture, scrotal color Doppler ultrasonography and transrectal ultrasonography, as well as sex hormones were analyzed. Among them, 238 reports from oligozoospermic/azoospermic infertile patients (P) fulfilling the inclusion criteria were considered for data analysis. Patients were subdivided into two groups according to follicle-stimulating hormone (FSH) values (Pa with FSH < 8 U/L and Pb with FSH ≥ 8 U/L). Sixty-three fertile volunteers (mean ± SD years) were enrolled as controls (C).

RESULTS

A higher prevalence of ultrasound abnormalities was recorded in P compared to C. Pb group had significantly lower bitesticular volume compared to Pa and C. Pa had a higher prevalence of transrectal ultrasonography abnormalities than Pb (69.9% vs. 38.4%), whereas Pb had a higher prevalence of abnormalities at scrotal color Doppler ultrasonography (60.0% vs. 28.3%, both p < 0.01). Bitesticular volume was inversely proportional to the number of altered seminal parameters and able to predict gonadotropin levels. A bitesticular volume <17 cc was associated with a higher risk of azoospermia (odds ratio = 1.799). Intratesticular vascularization was inversely correlated with gonadotropin levels and directly correlated with sperm count. A higher prevalence of prostate and seminal vesicle alterations was detected in patients and in Pa group, when compared with Pb group.

DISCUSSION AND CONCLUSION

Ultrasound abnormalities are correlated with seminal parameters and may guide the clinician in the diagnostic workflow of male infertility, suggesting spermatogenesis impairment or genital tract obstructions.

The Effect of Recombinant Human Follicle-Stimulating Hormone on Sperm Quality, Chromatin Status and Clinical Outcomes of Infertile Oligozoospermic Men Candidate for Intracytoplasmic Sperm Injection: A Randomized Clinical Trial

Background

Follicle-stimulating hormone (FSH) plays a crucial role in spermatogenesis; in this study, we assessed the effect of recombinant human FSH (rhFSH) on sperm parameters, chromatin status and clinical outcomes of infer- tile oligozoospermic men candidates for intracytoplasmic sperm injection (ICSI).

Materials and Methods

This interventional randomized clinical trials (IRCT) included 40 infertile oligozoospermic men undergoing ICSI. These individuals were randomized into two groups: 20 men received rhFSH drug for three months and the other 20 men who did not receive rhFSH drug were considered the control group. Before and 3 months after treatment initiation, sperm parameters (using computer-assisted semen analysis) and chromatin status [using chromomycin A3, aniline blue, and sperm chromatin dispersion (SCD) tests] were assessed in these individuals. Fur- thermore, hormonal profile was assessed using enzyme-linked immunosorbent assay (ELISA). Clinical outcomes of ICSI were also compared between the two groups.

Results

The rhFSH treated group showed a significant increase in the level of FSH, luteinizing hormone (LH), tes- tosterone (T) and prolactin (PRL), as well as significant improvements in sperm parameters compared to the control group. Also, after administration of rhFSH, there was asignificant reduction in the percentage of sperm DNA damage, protamine deficiency and chromatin immaturity, while such a reduction in these parameters was not observed in the control group. Moreover, the percentage of embryos with grade Aquality, was significantly higher in the rhFSH group compared to the control group. The pregnancy rate in the rhFSH group was higher than the control group but the dif- ference was insignificant.

Conclusion

Administration of rhFSH improves sperm quality in infertile oligozoospermic men and results in higher rates of good quality embryos post-ICSI (Registration number: IRCT20170923036334N2).

Prospects for FSH Treatment of Male Infertility

CONTEXT

Despite the new opportunities provided by assisted reproductive technology (ART), male infertility treatment is far from being optimized. One possibility, based on pathophysiological evidence, is to stimulate spermatogenesis with gonadotropins.

EVIDENCE ACQUISITION

We conducted a comprehensive systematic PubMed literature review, up to January 2020, of studies evaluating the genetic basis of follicle-stimulating hormone (FSH) action, the role of FSH in spermatogenesis, and the effects of its administration in male infertility. Manuscripts evaluating the role of genetic polymorphisms and FSH administration in women undergoing ART were considered whenever relevant.

EVIDENCE SYNTHESIS

FSH treatment has been successfully used in hypogonadotropic hypogonadism, but with questionable results in idiopathic male infertility. A limitation of this approach is that treatment plans for male infertility have been borrowed from hypogonadism, without daring to overstimulate, as is done in women undergoing ART. FSH effectiveness depends not only on its serum levels, but also on individual genetic variants able to determine hormonal levels, activity, and receptor response. Single-nucleotide polymorphisms in the follicle-stimulating hormone subunit beta (FSHB) and follicle-stimulating hormone receptor (FSHR) genes have been described, with some of them affecting testicular volume and sperm output. The FSHR p.N680S and the FSHB -211G>T variants could be genetic markers to predict FSH response.

CONCLUSIONS

FSH may be helpful to increase sperm production in infertile men, even if the evidence to recommend the use of FSH in this setting is weak. Placebo-controlled clinical trials, considering the FSHB-FSHR haplotype, are needed to define the most effective dosage, the best treatment length, and the criteria to select candidate responder patients.

Follicle-Stimulating Hormone Treatment and Male Idiopathic Infertility: Effects on Sperm Parameters and Oxidative Stress Indices according to FSHR c. 2039 A/G and c. -29 G/A Genotypes

Scientific evidence shows that the administration of follicle-stimulating hormone (FSH) to infertile patients with normal serum FSH concentrations improves sperm parameters in oligozoospermic men. The aim of this study was to evaluate the effects of highly purified urofollitropin (hpFSH) on conventional and bio-functional sperm parameters and on oxidative stress indices in patients with idiopathic infertility. We also evaluated the response to hpFSH on these parameters in relationship to FSHR c. 2039 A/G and FSHR c. -29 G/A genotypes. A prospective longitudinal study was conducted on 42 patients with idiopathic male infertility, 23 of whom underwent to FSHR c. 2039 A/G and FSHR c. -29 G/A genotyping. Each patient was asked to collect two semen samples before and after administration of 150 IU hpFSH three times a week for 16 weeks. Patients were divided into responders or non-responders based on whether their total sperm count had at least doubled or was less than double at the end of treatment, respectively. Responders showed a significantly higher semen volume, sperm concentration, spermatids, and leukocytes. Non-responders had a significant decrease of the percentage of spermatozoa in early apoptosis after hpFSH administration. Oxidative stress indexes did not differ significantly after FSH administration in both groups. Conventional and bio-functional sperm parameters did not differ in patients with FSHR c. 2039 GG and AA genotypes, and FSHR c. -29 GG genotype both before and after FSH administration. The FSHR c. 2039 and FSHR -29 G/A genotypes and allelic distribution did not differ between responders and non-responders. FSH showed to be capable of ameliorating sperm parameters in about half patients treated, therefore it may be helpful in patients with idiopathic infertility.

Use of Biosimilar Follicle-Stimulating Hormone in Asthenozoospermic Infertile Patients: A Multicentric Study

There is increasing data in favour of follicle-stimulating hormone (FSH) therapy in patients with oligo-asthenozoospermia and normal-range gonadotropins in order to increase sperm count and above all sperm motility. Some studies showed an improvement in DNA fragmentation and spontaneous pregnancy. Recently, biosimilar FSH has been marketed with the same indications. We performed a retrospective multicentric case-control study involving 147 asthenozoospermic patients between 18 and 45 years of age. A total of 97 patients were treated with biosimilar FSH 150 UI three times a week for 3 months, while 50 control subjects received no treatment. Patients were evaluated at baseline and after 3 months with semen analysis including DNA fragmentation, testicular colour Doppler ultrasound, and blood tests. Spontaneous pregnancies were recorded during a further follow-up period of 6 months. Treated patients showed after treatment a statistically significant increase in sperm concentration, total sperm count, and total motile sperm, as well as improved progressive motility and non-progressive motility. DNA fragmentation showed a significant reduction. Conversely, in the control group, no significant change was found. Pregnancy rate was significantly higher in treated patients. These data suggest comparable efficacy of biosimilar FSH in the treatment of male infertility; however, larger studies are needed to confirm our results.

Development of a novel next-generation sequencing panel for diagnosis of quantitative spermatogenic impairment

PURPOSE

To develop and assess a novel custom next-generation sequencing (NGS) panel for male infertility genetic diagnosis.

METHODS

A total of 241 subjects with diagnosis of idiopathic infertility ranging from azoospermia to normozoospermia were sequenced by a custom NGS panel including AR, FSHB, FSHR, KLHL10, NR5A1, NANOS1, SEPT12, SYCP3, TEX11 genes. Variants with minor allele frequency < 1% were confirmed by Sanger sequencing.

RESULTS

Nineteen missense variants were detected in 23 subjects with abnormal sperm count, whilst no variants were identified in normozoospermic men. Of identified variants, we prioritized variants classified as pathogenic and of uncertain significance (VUS) (63.1%, 12/19). No missense variants were found in males with normal seminal parameters (0/67). Therefore, the prevalence of variants was significantly higher in patients with spermatogenic impairment (16/174 vs 0/67, p = 0.007).

CONCLUSION

This study confirms the utility to apply NGS panel for infertility diagnosis in order to find new genetic variants potentially linked to male infertility with much higher accuracy than standard tests suggested by guidelines. Indeed, based on biological significance, prevalence in the general population and clinical data of patients, it is plausible that identified variants in this study might be linked to quantitative spermatogenic impairment, although further studies are needed.

Association of SNPs in GnRH gene with sperm quality traits of Chinese water buffalo

Hypothalamic gonadotropin-releasing hormone (GnRH) controls the activity of hypothalamic-pituitary-gonadal axis and plays a key role in the reproductive performance of animals. In this study, five single nucleotide polymorphisms (SNPs), namely g.991T > C, g.1041T > C g.3424T > C, g.3462C > A and g.3463Inde A, were detected in the GnRH gene of 162 water buffaloes by Sanger sequencing. Each SNP was associated with more than two sperm quality traits of ejaculate volume, sperm concentration, post-thaw sperm motility and sperm abnormality. g.3424T > C and g.3462C > A were related to these four traits and had a remarkable effect on ejaculate volume. The three other SNPs were related to sperm concentration, post-thaw sperm motility and sperm abnormality. Moreover, six haplotypes (H1: TCCAI, H2: CTTC-, H3: TCCCI, H4: CTTA-, H5: CCTA- and H6: CTCC-) composed of five SNPs comprising seven different combined genotypes were generated by linkage disequilibrium analysis. Statistics followed by one-way ANOVA indicated that water buffaloes with the haplotype combination H1H1 had the highest genotypic frequency, and those with the H4H4 haplotype combination had the highest ejaculate volume. The sperm concentration of those with haplotype combination H1H5 was higher than that of the other genotypes. In summary, our study showed a remarkable association between the SNPs of GnRH and sperm quality traits of Chinese water buffalo.

Genetics of male infertility

Male infertility is a multifactorial pathological condition affecting approximately 7% of the male population. The genetic landscape of male infertility is highly complex as semen and testis histological phenotypes are extremely heterogeneous, and at least 2,000 genes are involved in spermatogenesis. The highest frequency of known genetic factors contributing to male infertility (25%) is in azoospermia, but the number of identified genetic anomalies in other semen and aetiological categories is constantly growing. Genetic screening is relevant for its diagnostic value, clinical decision making, and appropriate genetic counselling. Anomalies in sex chromosomes have major roles in severe spermatogenic impairment. Autosome-linked gene mutations are mainly involved in central hypogonadism, monomorphic teratozoospermia or asthenozoospermia, congenital obstructive azoospermia, and familial cases of quantitative spermatogenic disturbances. Results from whole-genome association studies suggest a marginal role for common variants as causative factors; however, some of these variants can be important for pharmacogenetic purposes. Results of studies on copy number variations (CNVs) demonstrate a considerably higher CNV load in infertile patients than in normozoospermic men, whereas whole-exome analysis has proved to be a highly successful diagnostic tool in familial cases of male infertility. Despite such efforts, the aetiology of infertility remains unknown in about 40% of patients, and the discovery of novel genetic factors in idiopathic infertility is a major challenge for the field of androgenetics. Large, international, and consortium-based whole-exome and whole-genome studies are the most promising approach for the discovery of the missing genetic aetiology of idiopathic male infertility.

Clinical Use of FSH in Male Infertility

The established clinical indication for FSH use in male infertility is the treatment of patients with hypogonadotropic hypogonadism for stimulation of spermatogenesis that allows the induction of a clinical pregnancy in the female partner and finally the birth of a healthy child. Several clinical studies with urinary, purified, and recombinant FSH preparations in combination with hCG have demonstrated the high treatment efficacy regarding these clinical endpoints. Shortcomings of this hormone therapy are the long duration of treatment, sometimes longer than 2 years, and the inconvenience of injections every second or third day. However, improvements of therapy might be expected with new hormonal treatment options already available for infertility treatment in the female. FSH use for treatment of patients with normogonadotropic idiopathic infertility and oligozoospermia is still considered experimental in most countries. Recent meta-analyses have shown that FSH can significantly increase pregnancy rates in the female partners of these patients, but the effect-size is relatively low. Therefore, predictive factors for treatment success have to be identified, including FSH pharmacogenetics, to select the right normogonadotropic patients with idiopathic infertility for FSH therapy.

Pharmacogenetics of FSH Action in the Male

Male infertility is a major contributor to couple infertility, however in most cases it remains "idiopathic" and putative treatment regimens are lacking. This leads to a scenario in which intra-cytoplasmic spermatozoa injection (ICSI) is widely used in idiopathic male infertility, though the treatment burden is high for the couple and it entails considerable costs and risks. Given the crucial role of the Follicle-stimulating hormone (FSH) for spermatogenesis, FSH has been used empirically to improve semen parameters, but the response to FSH varied strongly among treated infertile men. Single nucleotide polymorphisms (SNPs) within FSH ligand/receptor genes (FSHB/FSHR), significantly influencing reproductive parameters in men, represent promising candidates to serve as pharmacogenetic markers to improve prediction of response to FSH. Consequently, several FSH-based pharmacogenetic studies have been conducted within the last years with unfortunately wide divergence concerning selection criteria, treatment and primary endpoints. In this review we therefore outline the current knowledge on single nucleotide polymorphisms (SNPs) in the FSH and FSH receptor genes and their putative functional effects. We compile and critically assess the previously performed pharmacogenetic studies in the male and propose a putative strategy that might allow identifying patients who could benefit from FSH treatment.

Effects of FSH on Sperm DNA Fragmentation: Review of Clinical Studies and Possible Mechanisms of Action

Sperm DNA fragmentation (sDF) is an important reproductive problem, associated to an increased time-to-pregnancy and a reduced success rate in natural and in vitro fertilization. sDF may virtually originate at any time of sperm's life: in the testis, in the epididymis, during transit in the ejaculatory ducts and even following ejaculation. Studies demonstrate that an apoptotic pathway, mainly occurring in the testis, and oxidative stress, likely acting in the male genital tract, are responsible for provoking the DNA strand breaks present in ejaculated spermatozoa. Although several pharmacological anti-oxidants tools have been used to reduce sDF, the efficacy of this type of therapies is questioned. Clearly, anti-apoptotic agents cannot be used because of the ubiquitous role of the apoptotic process in the body. A notable exception is represented by Follicle-stimulating hormone (FSH), which regulates testis development and function and has been demonstrated to exert anti-apoptotic actions on germ cells. Here, we review the existing clinical studies evaluating the effect of FSH administration on sDF and discuss the possible mechanisms through which the hormone may reduce sDF levels in infertile subjects. Although there is evidence for a beneficial effect of the hormone on sDF, further studies with clear and univocal patient inclusion criteria, including sDF cut-off levels and considering the use of a pharmacogenetic approach for patients selection are warranted to draw firm conclusions.