Androgens and spermatogenesis

The relationship between follicle-stimulating hormone and metabolic dysfunction-associated fatty liver disease in men

OBJECTIVES

The present study aimed to investigate the relationship between male hormones and metabolic dysfunction-associated fatty liver disease (MAFLD) in males.

METHODS

Data from the Fangchenggang Area Male Health and Examination Survey (FAMHES) were used to analyze the male hormone levels between MAFLD patients and controls. Univariate and multivariate logistic regression analyses were performed to identify risk factors for MAFLD. Receiver operating characteristic curve analysis was used to assess the diagnostic performance of male hormones for MAFLD.

RESULT

A total of 1578 individuals were included, with 482 individuals (30.54%) of MAFLD, including 293 (18.57%) with mild disease and 189 (11.98%) with moderate-to-severe disease. The MAFLD patients were significantly older than those without MAFLD. The LH, FSH, and SHBG levels in the MAFLD patients were significantly greater than those in the control group. Age, FSH, LH, SHBG, and estradiol were all risk factors for MAFLD. Age, FSH, and LH were risk factors for moderate-to-severe MAFLD. FSH was an independent risk factor for MAFLD and moderate-to-severe MAFLD. FSH showed an excellent diagnostic value, with an AUC of 0.992 alone and 0.996 after adjusting age.

CONCLUSIONS

Our findings indicate that FSH may be a potential diagnostic and predictive biomarker for MAFLD.

Management of Male Infertility with Coexisting Sexual Dysfunction: A Consensus Statement and Clinical Recommendations from the Asia-Pacific Society of Sexual Medicine (APSSM) and the Asian Society of Men's Health and Aging (ASMHA)

Male infertility (MI) and male sexual dysfunction (MSD) can often coexist together due to various interplay factors such as psychosexual, sociocultural and relationship dynamics. The presence of each form of MSD can adversely impact male reproduction and treatment strategies will need to be individualized based on patients' factors, local expertise, and geographical socioeconomic status. The Asia Pacific Society of Sexual Medicine (APSSM) and the Asian Society of Men's Health and Aging (ASMHA) aim to provide a consensus statement and practical set of clinical recommendations based on current evidence to guide clinicians in the management of MI and MSD within the Asia-Pacific (AP) region. A comprehensive, narrative review of the literature was performed to identify the various forms of MSD and their association with MI. MEDLINE and EMBASE databases were searched for the following English language articles under the following terms: "low libido", "erectile dysfunction", "ejaculatory dysfunction", "premature ejaculation", "retrograde ejaculation", "delayed ejaculation", "anejaculation", and "orgasmic dysfunction" between January 2001 to June 2022 with emphasis on published guidelines endorsed by various organizations. This APSSM consensus committee panel evaluated and provided evidence-based recommendations on MI and clinically relevant MSD areas using a modified Delphi method by the panel and specific emphasis on locoregional socio-economic-cultural issues relevant to the AP region. While variations exist in treatment strategies for managing MI and MSD due to geographical expertise, locoregional resources, and sociocultural factors, the panel agreed that comprehensive fertility evaluation with a multidisciplinary management approach to each MSD domain is recommended. It is important to address individual MI issues with an emphasis on improving spermatogenesis and facilitating reproductive avenues while at the same time, managing various MSD conditions with evidence-based treatments. All therapeutic options should be discussed and implemented based on the patient's individual needs, beliefs and preferences while incorporating locoregional expertise and available resources.

Hormone Regulation in Testicular Development and Function

The testes serve as the primary source of androgens and the site of spermatogenesis, with their development and function governed by hormonal actions via endocrine and paracrine pathways. Male fertility hinges on the availability of testosterone, a cornerstone of spermatogenesis, while follicle-stimulating hormone (FSH) signaling is indispensable for the proliferation, differentiation, and proper functioning of Sertoli and germ cells. This review covers the research on how androgens, FSH, and other hormones support processes crucial for male fertility in the testis and reproductive tract. These hormones are regulated by the hypothalamic-pituitary-gonad (HPG) axis, which is either quiescent or activated at different stages of the life course, and the regulation of the axis is crucial for the development and normal function of the male reproductive system. Hormonal imbalances, whether due to genetic predispositions or environmental influences, leading to hypogonadism or hypergonadism, can precipitate reproductive disorders. Investigating the regulatory network and molecular mechanisms involved in testicular development and spermatogenesis is instrumental in developing new therapeutic methods, drugs, and male hormonal contraceptives.

Predictive parameters of the efficacy of varicocele repair: a review

ABSTARCT

Varicocele has a prevalence of 15% in the population and represents a primary cause of infertility in 40% of cases and a secondary cause in approximately 80% of cases. It is considered the major correctable cause of male infertility. Despite its high prevalence in the infertile population, a large number of patients with varicocele do not experience reproductive difficulties. For this reason, it is still highly debated which parameters could be used to predict which patients with varicocele will be most likely to benefit from its repair. The main international and European guidelines state that treatment should only be considered in infertile patients with abnormal sperm quality. However, these guidelines do not help physicians to identify which of these patients may benefit from the treatment. Therefore, this narrative review collects the evidence in the literature on the usefulness of some factors as predictors of improvement, highlighting how some of them may be effective in an initial selection of patients to be treated, while others are promising but further studies are needed. Finally, a brief consideration on the possible role of artificial intelligence is proposed.

Intracerebroventricular PROK2 infusion could increase the secretion of male reproductive hormones by stimulating the HPG axis

BACKGROUND

Prokineticin 2 (PROK2), an important neuropeptide that plays a key role in the neuronal migration of gonadotropin-releasing hormone (GnRH) in the hypothalamus, is known to have regulatory effects on the gonads. In the present study, the impact of intracerebroventricular (icv) PROK2 infusion on hypothalamic-pituitary-gonadal axis (HPG) hormones, testicular tissues, and sperm concentration was investigated.

METHODS AND RESULTS

Rats were randomly divided into four groups: control, sham, PROK2 1.5 and PROK2 4.5. Rats in the PROK2 1.5 and PROK2 4.5 groups were administered 1.5 nmol and 4.5 nmol PROK2 intracerebroventricularly for 7 days via an osmotic mini pump (1 µl/h), respectively. Rat blood serum follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone hormone levels were determined with the ELISA method in the blood samples after 7 days of infusion. GnRH mRNA expression was determined with the RT-PCR in hypothalamus tissues. analyze Sperm concentration was determined, and testicular tissue was examined histologically with the hematoxylin-eosin staining method. It was observed that GnRH mRNA expression increased in both PROK2 infusion groups. Serum FSH, LH and testosterone hormone levels also increased in these groups. Although sperm concentration increased in PROK2 infusion groups when compared to the control and sham, the differences were not statistically significant. Testicular tissue seminiferous epithelial thickness was higher in the PROK2 groups when compared to the control and sham groups.

CONCLUSION

The present study findings demonstrated that icv PROK2 infusion induced the HPG axis. It could be suggested that PROK2 could be a potential agent in the treatment of male infertility induced by endocrinological defects.

Single-Cell Transcriptome Sequencing Reveals Molecular Expression Differences and Marker Genes in Testes during the Sexual Maturation of Mongolian Horses

This study aimed to investigate differences in testicular tissue morphology, gene expression, and marker genes between sexually immature (1-year-old) and sexually mature (10-year-old) Mongolian horses. The purposes of our research were to provide insights into the reproductive physiology of male Mongolian horses and to identify potential markers for sexual maturity. The methods we applied included the transcriptomic profiling of testicular cells using single-cell sequencing techniques. Our results revealed significant differences in tissue morphology and gene expression patterns between the two age groups. Specifically, 25 cell clusters and 10 cell types were identified, including spermatogonial and somatic cells. Differential gene expression analysis highlighted distinct patterns related to cellular infrastructure in sexually immature horses and spermatogenesis in sexually mature horses. Marker genes specific to each stage were also identified, including APOA1, AMH, TAC3, INHA, SPARC, and SOX9 for the sexually immature stage, and PRM1, PRM2, LOC100051500, PRSS37, HMGB4, and H1-9 for the sexually mature stage. These findings contribute to a deeper understanding of testicular development and spermatogenesis in Mongolian horses and have potential applications in equine reproductive biology and breeding programs. In conclusion, this study provides valuable insights into the molecular mechanisms underlying sexual maturity in Mongolian horses.

Asperosaponin VI protects against spermatogenic dysfunction in mice by regulating testicular cell proliferation and sex hormone disruption

ETHNOPHARMACOLOGICAL RELEVANCE

Studies have found that the causes of male infertility are complex, and spermatogenic dysfunction accounts for 30%-65% of male infertility causes, which is the main cause of male infertility. Asperosaponin VI (ASVI) is a saponin extracted from the traditional Chinese herb Dipsacus asperoides C.Y.Cheng & T.M.Ai. However, the precise protective impact and underlying mechanism of ASVI in the therapy of spermatogenic dysfunction remain unknown.

AIM OF THE STUDY

To investigate the impact of ASVI on the spermatogenic dysfunction induced by cytoxan (CTX) in mice, as well as explore any potential mechanisms.

MATERIALS AND METHODS

Potential ASVI targets were screened using the Pharmapper and Uniprot databases, while genes related to spermatogenic dysfunction were collected from the GeneCards database. The String and Cytoscape databases were then used for PPI analysis for the common targets of ASVI and spermatogenic dysfunction. Meanwhile, the Metascape database was used for KEGG and GO analysis. In vivo experiments, spermatogenic dysfunction was induced in male mice by intraperitoneal administration of CTX (80 mg/kg). To demonstrate the possible protective effects of ASVI on reproductive organs, CTX-induced spermatogenic dysfunction mice with different dosages of ASVI (0.8, 4, 20 mg/kg per day) treatment were collected and gonad weight was detected. The testis and epididymis were detected again by H&E. To assess the impact of ASVI on fertility in male mice, we analyzed sperm quality, serum hormones, sexual behavior, and fertility. The mechanism was investigated using WB, IF, IHC, and Co-IP technology.

RESULTS

The ASVI exhibited interactions with 239 associated targets. Furthermore, 1555 targets associated with spermatogenic dysfunction were predicted, and further PPI analysis identified 6 key targets. Among them, the EGFR gene exhibited the highest degree of connection and was at the core of the network. Based on the GO and KEGG enrichment analysis, ASVI may affect spermatogenic dysfunction through the EGFR pathway. In vivo experiments, ASVI significantly improved CTX-induced damage to male fertility and reproductive organs, increasing sperm quality. At the same time, ASVI can resist CTX-induced testicular cell damage by increasing p-EGFR, p-ERK, PCNA, and p-Rb in the testis and by promoting the interaction of CyclinD1 with CDK4. In addition, ASVI can also regulate sex hormone disorders and protect male fertility.

CONCLUSIONS

ASVI improves CTX-induced spermatogenesis dysfunction by activating the EGFR signaling pathway and regulating sex hormone homeostasis, which may be a new potential protective agent for male spermatogenic dysfunction.

Effects of the adsorption behavior of polyamide microplastics on male reproductive health by reduction of testosterone bioavailability

Microplastics (MPs) are global environmental pollutants with potential toxicity concerns, and their effects on the reproductive system have attracted increasing attention. This study investigated the interaction between MPs and mammalian biomolecules, focusing on the relationship between the testosterone adsorption behavior of MPs and male reproductive health. The adsorption capacity of different types of MPs for testosterone was evaluated in vitro experiments. Polyamide (PA)-MPs exhibited stronger adsorption, while polymethyl methacrylate (PMMA)-MPs displayed the weakest adsorption. Sorption equilibrium between PA-MPs and testosterone was achieved within 6 h, fitting the Pseudo-2nd-order model and Langmuir isotherm. The effects of MPs on male reproduction in mice was determined in vivo experiments. Male mice were treated with 0.1 and 0.5 mg/d PA-MPs/PMMA-MPs by gavage once per day for 28 days. The results showed that only 0.5 mg/d PA-MP exposure induced decreased serum testosterone levels, increased testicular testosterone levels compared to the control, and more severe damage to seminiferous tubule structure, sperm motility and sperm morphology compared to the PMMA-MPs group. Meanwhile, PA-MPs could reduce intracellular nuclear translocation of androgen receptor (AR) mediated by testosterone, while PMMA-MPs had no impact. The study revealed that PA-MP adsorption reduced testosterone bioavailability and caused sperm quality to decline, offering new insights into the combined toxicity mechanism of MPs in male mammals.

Mitigative potential of kaempferide against polyethylene microplastics induced testicular damage by activating Nrf-2/Keap-1 pathway

Polyethylene microplastics (PE-MPs) are one of the environmental contaminants that instigate oxidative stress (OS) in various organs of the body, including testes. Kaempferide (KFD) is a plant-derived natural flavonol with potential neuroprotective, hepatoprotective, anti-cancer, anti-oxidant and anti-inflammatory properties. Therefore, the present study was designed to evaluate the alleviative effects of KFD against PE-MPs-prompted testicular toxicity in rats. Fourty eight adult male albino rats were randomly distributed into 4 groups: control, PE-MPs-administered (1.5 mgkg-1), PE-MPs (1.5 mgkg-1) + KFD (20 mgkg-1) co-treated and KFD (20 mgkg-1) only treated group. PE-MPs intoxication significantly (P < 0.05) lowered the expression of Nrf-2 and anti-oxidant enzymes, while increasing the expression of Keap-1. The activities of anti-oxidants i.e., catalase (CAT), glutathione reductase (GSR), superoxide dismutase (SOD), hemeoxygene-1 (HO-1) and glutathione peroxidase (GPx) were reduced, besides malondialdehyde (MDA) and reactive oxygen species (ROS) contents were increased significantly (P < 0.05) following the PE-MPs exposure. Moreover, PE-MPs exposure significantly (P < 0.05) reduced the sperm motility, viability and count, whereas considerably (P < 0.05) increased the dead sperm number and sperm structural anomalies. Furthermore, PE-MPs remarkably (P < 0.05) decreased steroidogenic enzymes and Bcl-2 expression, while increasing the expression of Caspase-3 and Bax. PE-MPs exposure significantly (P < 0.05) reduced the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone, whereas inflammatory indices were increased. PE-MPs exposure also induced significant histopathological damages in the testes. Nevertheless, KFD supplementation significantly (P < 0.05) abrogated all the damages induced by PE-MPs. The findings of our study demonstrated that KFD could significantly attenuate PE-MPs-instigated OS and testicular toxicity, due to its anti-oxidant, anti-inflammatory, androgenic and anti-apoptotic potential.

Leydig cell metabolic disorder act as a new mechanism affecting for focal spermatogenesis in Klinefelter syndrome patients: a real world cross-sectional study base on the age

Background

Klinefelter's syndrome (KS) was once considered infertile due to congenital chromosomal abnormalities, but the presence of focal spermatozoa changed this. The key to predict and promote spermatogenesis is to find targets that regulate focal spermatogenesis.

Objective

To explore the trend of fertility changes in KS patients at different ages and identify potential therapeutic targets.

Methods

Bibliometric analysis was used to collect clinical research data on KS from the Web of Science Core Collection (WoSCC) from 1992 to 2022. A cross-sectional study was conducted on 75 KS patients who underwent microscopic testicular sperm extraction (mTESE) from 2017 to 2022 in the real world. The reproductive hormones, testicular histopathology, androgen receptors, insulin-like factor 3 (INSL3) receptors and sperm recovery rate (SRR) were analyzed.

Results

Male infertility, dysplasia, Sertoli cells, Leydig cells, testosterone and spermatogenesis were the research focuses related to KS. Luteinizing hormone (LH), testosterone, and INSL3 were evaluation indicators of Leydig cell function that fluctuate with age. Testosterone and LH peaked at ages 13-19 and 30-45, while INSL3 only peaked at ages 13-19. 27 patients (27/75) recovered sperm through mTESE and experienced SRR peaks at the ages of 20, 28, 34, and 37. The SRR of fibrosis patients was 46.15%, fatty degeneration was 7.14%, and melanosis was 40.00%. The INSL3 and androgen receptors were highly expressed and roughly balanced in focal spermatogenesis.

Conclusion

Abnormal metabolism of Leydig cells led to imbalanced expression of INSL3 and androgen receptors, which might be a potential target for spermatogenesis in KS.

Emerging micropollutants in aquatic ecosystems and nanotechnology-based removal alternatives: A review

There is a significant concern about the accessibility of uncontaminated and safe drinking water, a fundamental necessity for human beings. This concern is attributed to the toxic micropollutants from several emission sources, including industrial toxins, agricultural runoff, wastewater discharges, sewer overflows, landfills, algal blooms and microbiota. Emerging micropollutants (EMs) encompass a broad spectrum of compounds, including pharmaceutically active chemicals, personal care products, pesticides, industrial chemicals, steroid hormones, toxic nanomaterials, microplastics, heavy metals, and microorganisms. The pervasive and enduring nature of EMs has resulted in a detrimental impact on global urban water systems. Of late, these contaminants are receiving more attention due to their inherent potential to generate environmental toxicity and adverse health effects on humans and aquatic life. Although little progress has been made in discovering removal methodologies for EMs, a basic categorization procedure is required to identify and restrict the EMs to tackle the problem of these emerging contaminants. The present review paper provides a crude classification of EMs and their associated negative impact on aquatic life. Furthermore, it delves into various nanotechnology-based approaches as effective solutions to address the challenge of removing EMs from water, thereby ensuring potable drinking water. To conclude, this review paper addresses the challenges associated with the commercialization of nanomaterial, such as toxicity, high cost, inadequate government policies, and incompatibility with the present water purification system and recommends crucial directions for further research that should be pursued.

Dendrobium officinale polysaccharides improved reproductive oxidative stress injury in male mice treated with cyclophosphamide

Polysaccharides from Dendrobium officinale polysaccharides (DOPs) are the main bioactive components of Dendrobium officinale, which have the functions of antioxidation and immune regulation. However, it is not clear whether DOPs have any effect on the prevention of reproductive disorders induced by oxidative stress. The purpose of this study was to explore the protective effect of DOPs on reproductive oxidative stress injury in male mice and its possible mechanism. In this study, the mouse model of reproductive injury was established by intraperitoneal injection of cyclophosphamide (CTX). The reproductive function was evaluated by relative testicular mass, sperm parameters, and sex hormone levels. The oxidative stress level of male mice with reproductive injury treated with DOPs was analyzed by the levels of 8-hydroxydeoxyguanosine (8-OHdG), malondialdehyde (MDA), and nitric oxide (NO) in sperm. The expression of follicle-stimulating hormone receptor (FSHR) mRNA, androgen-binding (ABP) mRNA, and c-kit mRNA was detected by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) to explore its mechanism. After CTX administration, the sperm density, sperm motility, normal sperm morphology, and sex hormone levels in mice were significantly lower than those in the control group (P < 0.05). At the same time, the expression of p53 protein was upregulated, and the expression of Bcl-2 protein was downregulated (P < 0.05). In addition, the expression of FSHR and ABP mRNA on Sertoli cells was also significantly inhibited (P < 0.05). DOPs can effectively reduce the oxidative stress injury of testicular tissue. After DOP treatment, the sperm quality and sex-related hormone levels of mice were significantly improved and positively correlated with the dose of DOPs (P < 0.05). Administration of DOPs can reduce the damage caused by oxidative stress by reducing the level of oxidative stress, improving the hormone environment in testes, and regulating the expression of specific genes in Sertoli cells and spermatogenic cells.

Sertoli cell-derived extracellular vesicles traverse the blood-testis barrier and deliver miR-24-3p inhibitor into germ cells improving sperm mobility

Asthenozoospermia, characterized by poor sperm motility, is a common cause of male infertility. Improving energy metabolism and alleviating oxidative stress through drug regimens are potential therapeutic strategies. In this study, we observed upregulated miR-24-3p levels in asthenozoospermia spermatozoa, contributing to energy metabolism disorder and oxidative stress by reducing GSK3β expression. Thus, reducing miR-24-3p levels using drugs is expected to improve sperm motility. The blood-testis barrier (BTB) protects the testis from xenobiotics and drugs. In this study, we found that Sertoli cell-derived small extracellular vesicles (SC-sEV) can traverse the BTB and enter germ cells. We successfully loaded miR-24-3p inhibitor into SC-sEV, creating the nano-drug SC-sEV@miR-24-3p inhibitor, which effectively delivers miR-24-3p inhibitor into germ cells. In a gossypol-induced mouse asthenozoospermia model, administration of SC-sEV@miR-24-3p inhibitor significantly improved sperm motility, in vitro fertilization success, and blastocyst formation rates. As anticipated, it also improved the litter size of asthenozoospermia mice. These results suggest that SC-sEV@miR-24-3p inhibitor holds promise as a potential clinical treatment for asthenospermia.

Ameliorative effects of propolis upon reproductive toxicity in males

Propolis is a sticky natural product produced by honeybees. Research studies have discussed the effectiveness of propolis, directly or indirectly, for ameliorating reproductive toxicity in males; however, this research has not yet been reviewed. The current paper presents an integrative summary of all research studies in Scopus and PubMed that investigated the effects of propolis on semen quality, and hence on male fertility, in conditions of reproductive toxicity. The consensus indicates that propolis ameliorates reproductive toxicity and enhances semen quality in vivo in test animals. These effects may be attributable to the ability of propolis to reduce testicular oxidative damage, enhance testicular antioxidant defense mechanisms, increase nitric oxide production, reduce testicular apoptotic injury, and boost testosterone production. However, to generalize these effects in humans would require further research.

Ameliorating effect of Mucuna pruriens seed extract on sodium arsenite-induced testicular toxicity and hepato-renal histopathology in rats

Background and Aim

A significant cause of arsenic poisoning is polluted groundwater. Arsenic poisoning results in the suppression of spermatogenesis and the liver and kidneys are vulnerable to the toxic effects as well. Mucuna pruriens has been identified to have fertility-enhancing and anti-lipid peroxidation properties. Based on these properties of M. pruriens, this study aimed to investigate the efficacy of M. pruriens seed extract in reducing sodium arsenite-induced testicular impairment and hepato-renal histopathology in rats.

Materials and Methods

The study was divided into two groups; short-term (45 days) and long-term (90 days) treatment groups and each group was divided into nine subgroups. Subgroups 1 and 2 served as normal and N-acetyl cysteine (NAC) controls, respectively. Subgroups 3-9 received sodium arsenite in the drinking water (50 mg/L). Subgroup-4 received NAC (210 mg/kg body weight [BW]) orally once daily. Subgroups 5-7 received aqueous seed extract of M. pruriens (350, 530, and 700 mg/kg BW, respectively) orally once daily. Subgroups 8 and 9 received a combination of NAC and aqueous seed extract (350 and 530 mg/kg BW, respectively) orally once daily. Following the treatment, animals were sacrificed and sperm parameters and DNA damage were evaluated. Testis, liver, and kidneys were analyzed for histopathology.

Results

Sodium arsenite-induced a significant reduction in sperm parameters and increase in the abnormal architecture of spermatozoa. Histology revealed tissue necrosis. The M. pruriens seed extract ameliorated the damaging effects of sodium arsenite with respect to tissue architecture and sperm parameters when coadministered.

Conclusion

Mucuna pruriens has beneficial effects against the deleterious effects of sodium arsenite on various tissues. Thus, M. pruriens (530 and 700 mg/kg BW) supplementation would reduce the adverse changes observed with sodium arsenite exposure.

Toxic effects of per- and polyfluoroalkyl substances on sperm: Epidemiological and experimental evidence

As emerging organic contaminants, per- and polyfluoroalkyl substances (PFASs) have aroused worldwide concern due to their environmental persistence, ubiquitous presence, bioaccumulation, and potential toxicity. It has been demonstrated that PFASs can accumulate in human body and cause multiple adverse health outcomes. Notably, PFASs have been detected in the semen of human, posing a potential hazard to male fecundity. This article reviews the evidence about the toxic effects of exposure to PFASs on male reproduction, focusing on the sperm quality. Epidemiological studies showed that PFASs, such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), were adversely associated with the semen parameters in humans, including sperm count, morphology and motility. Experimental results also confirmed that PFAS exposure led to testicular and epididymal damage, therefore impairing spermatogenesis and sperm quality. The mechanisms of reproductive toxicity of PFASs may be involved in blood-testosterone barrier destruction, testicular apoptosis, testosterone synthesis disorder, and membrane lipid composition alteration, oxidative stress and Ca²⁺ influx in sperm. In conclusion, this review highlighted the potential threat of exposure to PFASs to human spermatozoa.

Revisiting the gonadotropic regulation of mammalian spermatogenesis: evolving lessons during the past decade

Spermatogenesis is a multi-step process of male germ cell (Gc) division and differentiation which occurs in the seminiferous tubules of the testes under the regulation of gonadotropins - Follicle Stimulating Hormone (FSH) and Luteinising hormone (LH). It is a highly coordinated event regulated by the surrounding somatic testicular cells such as the Sertoli cells (Sc), Leydig cells (Lc), and Peritubular myoid cells (PTc). FSH targets Sc and supports the expansion and differentiation of pre-meiotic Gc, whereas, LH operates via Lc to produce Testosterone (T), the testicular androgen. T acts on all somatic cells e.g.- Lc, PTc and Sc, and promotes the blood-testis barrier (BTB) formation, completion of Gc meiosis, and spermiation. Studies with hypophysectomised or chemically ablated animal models and hypogonadal (hpg) mice supplemented with gonadotropins to genetically manipulated mouse models have revealed the selective and synergistic role(s) of hormones in regulating male fertility. We here have briefly summarized the present concept of hormonal control of spermatogenesis in rodents and primates. We also have highlighted some of the key critical questions yet to be answered in the field of male reproductive health which might have potential implications for infertility and contraceptive research in the future.

Genome-wide alternation and effect of DNA methylation in the impairments of steroidogenesis and spermatogenesis after PM2.5 exposure

The effects of ambient fine particles on male reproductive health have raised widespread concern. The particular underlying mechanisms of the damage remain largely unclear and demand more research in new directions. Previous research has revealed that DNA methylation plays an important role in male reproductive development and is also vulnerable to environmental influences. However, there hasn't been enough investigation into the involvement of DNA methylation in PM_2.5-induced male reproductive toxicity. Here, we establish a real-time PM_2.5 exposure model and revealed that PM_2.5 exposure could lead to testicular dysfunction including spermatogenesis impairment and steroid hormone dysfunction. In particular, the decrease in the testicular global level of 5-methylcytosine (5mC) indicated a possible association of DNA methylation with testicular injury induced by PM_2.5 exposure. Further genome-wide methylation analysis revealed genomic hypomethylation of testicular DNA and identified more than 1000 differentially methylated regions in both CAP and UA versus FA, indicating that PM_2.5 exposure, even low-dose, could modulate the testicular methylome. Furthermore, integrated analysis of methylome and transcriptome identified some key methylated genes and networks, which may be involved in spermatogenesis and synthesis of steroid hormone. The testicular methylation levels of key genes especially Cyp11a1 and Pax8 raised, and their consequent reduced expression may impair the testosterone and sperm production process. Our research provides fundamental knowledge as well as novel insights into the possible involvement of DNA methylation in PM_2.5-induced male reproductive harm.

Untoward Azoospermia by absurd testosterone therapy

The established role of the male partner in overall infertility is almost 50%.1 The most significant cause is degraded number as well as the quality of sperms.2 Spermatogenesis is governed by gonadotropin-releasing hormone (GnRH) then follicle-stimulating hormone (FSH) and finally by testosterone, which is linked with puberty, and essentially required well controlled hypothalamic-pituitary axis leading the Leydig cells along with Sertoli cells.3 In Pakistan incidence of azoospermia is 12.32%, and another study reported it to be 16%, this incidence is comparable to infertility in the USA at 10% while 11.35% in Kenya.4The non-obstructive azoospermia (NOA) is mostly treated with testicular sperm extraction and then intracytoplasmic sperm injection (ICSI), but only a small percentage can afford it, and mostly it requires multiple attempts. So, most couples end up with adaptation or sperm donation.5,6 One percent of all men and 10% of infertile are azoospermic. In non-obstructive azoospermia primary testicular failure occur, testosterone therapy (TTh) negative feedback mechanism can cause suppression of luteinizing hormone (LH).7 In 30% of infertile men, the cause cannot be established, but genetics, chronic infection, prostatitis, anti-sperm antibodies, and persistent obesity can lead to it.8Unfortunately, in Pakistan, most of our physicians are fond of prescribing a high dosage of testosterone for the long term, to infertile male patients. Patients become satisfied due to the positive characteristics of testosterone, but the most painful aspect is that high TTh leads to complete azoospermia. Moreover, in most such cases, it is permanent due to damage to the germinal layer. More than six-month high TTh is contraceptive.9 In 2018 the Endocrine Society and the American Urological Association recommend testosterone therapy to treat infertility and preserve fertility.10 The first management of such cases is the cessation of TTh. An integrated analysis of 1549 men on high TTh was reported as the median time to recover was 3.4 months, to a sperm concentration of 20 million/ mL and the median time to recover to baseline sperm concentration was 5.4 months.10 According to this analysis, 90% of men recovered in 12-month time after stopping TTh with 20 million/ml sperms, and 100% recovered after 24 months, all of them were on average 31.8 years of age. They were on TTh for 9.5 months.11 Hypothalamic-pituitary-gonadal (HPG) axis is almost terminated by testosterone replacement therapy (TRT) and anabolic androgenic steroids (AAS) resulting in very much suppressed or even the complete arrest of the spermatogenesis. Spontaneous cessation of such overwhelming male infertility treatments can recover spermatogenesis depending upon the length and strength of such treatments.12,13 The Prime concern is the weightage of the decision by a physician to start such therapies, which have an abusive role in treating infertility. Most physicians are unfortunately causing such azoospermia.Many very reputed international guidelines and recommendations are against such TTh, TRT, and even AAS for the treatment of male infertility. Clomiphene citrate (CC) and human chorionic gonadotropin (HCG) along with the revival of the hypothalamic-pituitary-gonadal axis can help to restore spermatogenesis in these men, after 1-2 years of the cessation of the TTh.14

Prokineticin 2/PROK2 and Male Infertility

Male infertility represents about 50% of the causes of infertility in couples. The diagnosis process represents an important procedure for defining, when possible, the causes and approaching treatments (pharmacological, surgical) aimed at overcoming the problem. Several scientific studies have set out to discover early and indicative markers capable of providing information on the biological origin of infertility and increase current knowledge in the context of new potential therapeutic approaches. The prokineticin system (PROK) consists of the prokineticin 1 (PROK1) and prokineticin 2 (PROK2) proteins. Through the activation of two G-protein receptors (PROKR1 and PROKR2) regulate a wide range of biological functions, including gastrointestinal motility, circadian rhythm regulation, neurogenesis, angiogenesis, pain perception, and mood regulation. Several studies have highlighted the crucial role of the PROK system in the development and maturation of both male and female human reproductive organs. Particularly in men, the PROK system represents a new system useful to clarify some aspects of testicular pathophysiology and provide new potential hypotheses for therapeutic intervention. This narrative review aims to illustrate the state of the art regarding, in particular, the role of PROK2 in male infertility.