Assessment of hormonal status in male infertility. An update

The role of Cistanches Herba and its ingredients in improving reproductive outcomes: A comprehensive review

BACKGROUND

Infertility patients account for an astonishing proportion of individuals worldwide. Due to its complex etiology and challenging treatment, infertility has imposed significant psychological and economic burdens on many patients. C. Herba (Cistanche tubulosa (Schenk) Wight and Cistanche deserticola Ma), renowned as one of the most prominent Chinese herbal medicines (CHMs), is abundant in diverse bioactive compounds that exhibit therapeutic effects on many diseases related to oxidative stress (OS) and disorders of sex hormone levels.

OBJECTIVE

Due to the limited drugs currently used in clinical practice to improve reproductive outcomes and their inevitable side effects, developing safe and effective new medications for infertility is of significance. This article comprehensively reviewed the phytochemicals of C. Herba, focusing on their efficacy and mechanisms on infertility and their safety for the first time, aiming to offer valuable insights for the development and application of C. Herba, and for developing novel strategies for treating infertility.

METHODS

We used "Cistanche" and its known bioactive components in combination with "sperm", "testicles", "epididymis", "ovaries", "uterus", and "infertility" as keywords to search in PubMed, Web of Science, Scopus and CNKI up to November 2023. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guideline was followed.

RESULTS

The therapeutic effects of C. Herba on infertility are mainly attributed to echinacoside (ECH), verbascoside (VB), salidroside (SAL), polysaccharides, and betaine. They can effectively improve spermatogenic dysfunction, gonadal dysfunction and erectile dysfunction (ED) by exerting anti-oxidation, sex hormones regulation and anti-hypoxia. Moreover, they can also improve premature ovarian failure (POF), ovarian and uterine cancer, oocyte maturation by exerting anti-oxidation, anti-apoptosis, and anti-cancer. C. Herba and its active ingredients also exhibit pleasing safety.

CONCLUSION

C. Herba is a promising source of natural medicine for infertility. Additionally, compared to current therapeutic drugs, its favorable safety also supports its development as a nutritional supplement. However, high-quality clinical studies are required to validate its effectiveness for the development of novel therapeutic strategies.

Association between embryo morphokinetic development and intracytoplasmic sperm injection with epididymal sperm via time-lapse imaging

The objective of this study was to investigate the impact of sperm source on embryo morphokinetics and the clinical outcomes of intracytoplasmic sperm injection (ICSI) cycles by considering the clustering of data (multiple embryos per patient that share a comparable developmental timing). This matched cohort study was performed at a private university-affiliated in vitro fertilization center. Women who underwent ICSI with epididymal sperm between January 2019 and December 2020 (the percutaneous epididymal sperm aspiration group, n = 32 cycles) were matched with women who underwent ICSI with ejaculated sperm because of idiopathic male factor infertility (the male factor infertility [MFI] group, n = 32 cycles) or female infertility (the control group, n = 32 cycles). Embryos were cultured in a time-lapse imaging incubator, and morphokinetic development was recorded and compared among the groups. Significantly slower divisions were observed in embryos derived from epididymal sperm than in those derived from the MFI and control groups. Embryos derived from epididymal sperm had a significantly lower KIDScore (3.1 ± 0.2) than did those derived from ejaculated spermatozoa from the MFI (5.4 ± 0.1) and control (5.6 ± 0.2, p < 0.001) groups. Epididymal sperm-derived embryos showed a significantly greater occurrence of multinucleation (23.2%) than did those derived from ejaculated sperm from the MFI and control groups (2.8% and 3.7%, p < 0.001, respectively). Epididymal sperm-derived embryos were significantly more likely to undergo direct or reverse cleavage (11.1%) than ejaculated sperm-derived embryos in the control group (4.3%, p = 0.001). In conclusion, delayed cell cleavage and increased incidences of blastomere multinucleation and abnormal cleavage patterns are observed when epididymal-derived sperm are used for ICSI.

Genome-wide analyses identify 21 infertility loci and over 400 reproductive hormone loci across the allele frequency spectrum

Genome-wide association studies (GWASs) may help inform treatments for infertility, whose causes remain unknown in many cases. Here we present GWAS meta-analyses across six cohorts for male and female infertility in up to 41,200 cases and 687,005 controls. We identified 21 genetic risk loci for infertility (P≤5E-08), of which 12 have not been reported for any reproductive condition. We found positive genetic correlations between endometriosis and all-cause female infertility (rg=0.585, P=8.98E-14), and between polycystic ovary syndrome and anovulatory infertility (rg=0.403, P=2.16E-03). The evolutionary persistence of female infertility-risk alleles in EBAG9 may be explained by recent directional selection. We additionally identified up to 269 genetic loci associated with follicle-stimulating hormone (FSH), luteinising hormone, oestradiol, and testosterone through sex-specific GWAS meta-analyses (N=6,095-246,862). While hormone-associated variants near FSHB and ARL14EP colocalised with signals for anovulatory infertility, we found no rg between female infertility and reproductive hormones (P>0.05). Exome sequencing analyses in the UK Biobank (N=197,340) revealed that women carrying testosterone-lowering rare variants in GPC2 were at higher risk of infertility (OR=2.63, P=1.25E-03). Taken together, our results suggest that while individual genes associated with hormone regulation may be relevant for fertility, there is limited genetic evidence for correlation between reproductive hormones and infertility at the population level. We provide the first comprehensive view of the genetic architecture of infertility across multiple diagnostic criteria in men and women, and characterise its relationship to other health conditions.

Environmental and occupational exposure to cadmium associated with male reproductive health risk: a systematic review and meta-analysis based on epidemiological evidence

There is an abundance of epidemiological evidence and animal experiments concerning the correlation between cadmium exposure and adverse male reproductive health outcomes. However, the evidence remains inconclusive. We conducted a literature search from PubMed, Embase, and Web of Science over the past 3 decades. Pooled r and 95% confidence intervals (CIs) were derived from Cd levels of the type of biological materials and different outcome indicators to address the large heterogeneity of existing literature. Cd was negatively correlated with semen parameters (r = - 0.122, 95% CI - 0.151 to - 0.092) and positively correlated with sera sex hormones (r = 0.104, 95% CI 0.060 to 0.147). Among them, Cd in three different biological materials (blood, semen, and urine) was negatively correlated with semen parameters, while among sex hormones, only blood and urine were statistically positively correlated. In subgroup analysis, blood Cd was negatively correlated with semen density, sperm motility, sperm morphology, and sperm count. Semen Cd was negatively correlated with semen concentration. As for serum sex hormones, blood Cd had no statistical significance with three hormones, while semen Cd was negatively correlated with testosterone. In summary, cadmium exposure might be associated with the risk of a decline in sperm quality and abnormal levels of sex hormones.

A Comprehensive Review of the Impact of Chromium Picolinate on Testicular Steroidogenesis and Antioxidant Balance

Low testosterone (T) levels are a major cause of male infertility, as this hormone is crucial for several processes throughout the entire male reproductive tract. Leydig cells (LC) produce T through testicular steroidogenesis. Disrupted LC function can hinder steroid production and fertility. Among the factors that affect steroidogenesis, endocrine-disrupting chemicals (EDCs) raise concerns, as they disturb hormonal signaling. Chromium is classified as an EDC, and its main forms are hexavalent (Cr(VI)) and trivalent chromium (Cr(III)). While Cr(III) is controversially regarded as an essential metal, its compound Cr(III) picolinate (CrPic3) is used as a nutritional supplement due to its antidiabetic and antioxidant properties. This review aims to identify the possible effects of CrPic3 on testicular steroidogenesis and thus, on male fertility. The detriments caused by CrPic3 in LC include the inhibition of enzymes involved in steroidogenesis, and, as in other cells, the induction of mutagenesis and apoptosis. Remarkably, CrPic3 impacts male fertility through the alteration of reactive oxygen species (ROS), T levels, and sperm parameters (sperm motility and abnormal sperm count). However, gaps and inconsistencies exist in the literature concerning its effects on male fertility. Thus, further research is imperative to comprehend the underlying mechanisms of CrPic3 in the physiological processes relevant to male fertility, ensuring the supplement's safety for use by men.

The Effects of Bisphenol A on Human Male Infertility: A Review of Current Epidemiological Studies

Endocrine disruptor chemicals (EDCs) can have a harmful effect on the human body's endocrine system and thus adversely affect the development, reproduction, neurological, cardiovascular, and immune systems and metabolism in humans and wildlife. According to the World Health Organization, EDCs are mostly man-made and found ubiquitously in our daily lives, notably in pesticides, metals, and additives or contaminants in food and personal care products. Human exposure occurs through ingestion, inhalation, and dermal contact. Bisphenol A (BPA) is a proven EDC capable of mimicking or blocking receptors and altering hormone concentrations and metabolism. Although consumed in low doses, it can stimulate cellular responses and affect the body's functions. In humans, exposure to BPA has been correlated with the onset or development of several diseases. This literature review aimed to verify the effects of BPA on human male infertility using the most recently published literature. Thus, this review allowed us to conclude that this compound seems to have harmful effects on human male fertility, causing changes in hormonal and semen characteristics. However, these conclusions lack more robust and reproducible scientific studies. Even so, and since male infertility prevalence is increasing, preventive measures must be taken to ensure male fertility.

An Analysis of the Structural Relationship between Thyroid Hormone-Signaling Disruption and Polybrominated Diphenyl Ethers: Potential Implications for Male Infertility

Polybrominated diphenyl ethers (PBDEs) are a common class of anthropogenic organobromine chemicals with fire-retardant properties and are extensively used in consumer products, such as electrical and electronic equipment, furniture, textiles, and foams. Due to their extensive use, PBDEs have wide eco-chemical dissemination and tend to bioaccumulate in wildlife and humans with many potential adverse health effects in humans, such as neurodevelopmental deficits, cancer, thyroid hormone disruption, dysfunction of reproductive system, and infertility. Many PBDEs have been listed as chemicals of international concern under the Stockholm Convention on Persistent Organic Pollutants. In this study, the aim was to investigate the structural interactions of PBDEs against thyroid hormone receptor (TRα) with potential implications in reproductive function. Structural binding of four PBDEs, i.e., BDE-28, BDE-100, BDE-153 and BDE-154 was investigated against the ligand binding pocket of TRα using Schrodinger's induced fit docking, followed by molecular interaction analysis and the binding energy estimation. The results indicated the stable and tight binding of all four PDBE ligands and similarity in the binding interaction pattern to that of TRα native ligand, triiodothyronine (T3). The estimated binding energy value for BDE-153 was the highest among four PBDEs and was more than that of T3. This was followed by BDE-154, which is approximately the same as that of TRα native ligand, T3. Furthermore, the value estimated for BDE-28 was the lowest; however, the binding energy value for BDE-100 was more than BDE-28 and close to that of TRα native ligand, T3. In conclusion, the results of our study suggested the thyroid signaling disruption potential of indicated ligands according to their binding energy order, which can possibly lead to disruption of reproductive function and infertility.

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

New Insight on the In Vitro Effects of Melatonin in Preserving Human Sperm Quality

Spermatozoa (SPZ) are sensitive to stressful conditions, particularly oxidative stress, which alters their quality; thus, the use of protective molecules as an antioxidant is encouraged. Herein, we used melatonin (MLT) to investigate its in vitro effects on human sperm parameters under conditions of oxidative stress induced by cadmium (Cd). Fifteen human semen samples were divided into control, Cd-treated, MLT-treated, and Cd+MLT-treated groups and analyzed after 30 min, 6 h, and 24 h of exposure. Results showed a time-dependent decrease in SPZ motility, DNA integrity, and increased apoptosis induced by oxidative stress, and these effects were counteracted by MLT co-treatment. Based on these data, we further explored additional parameters just at 24 h. The induced oxidative stress, highlighted by the increased lipid peroxidation, reduced the percentage of SPZ able to undertake acrosome reaction and altered the levels and localization of some protein markers of motility (PREP, RSPH6A), morphology (DAAM1), and acrosome membrane (PTMA, IAM38); all these effects were counteracted by MLT co-treatment. Interestingly, MLT alone was able to ameliorate motility at 30 min of incubation compared to the control, while at 24 h, it prevented the physiological alteration in terms of motility, DNA integrity, and apoptosis. Collectively, the data encourage MLT use as an integrative molecule to ameliorate human gamete quality when compromised by stressful conditions.