The Role of Estrogen Modulators in Male Hypogonadism and Infertility

Selective modulation of estrogen receptor in obese men with androgen deficiency: A systematic review and meta-analysis

BACKGROUND

Although selective estrogen receptor modulators have been proposed as a treatment for men with central functional hypogonadism, only a few data have been produced in men with obesity-related functional androgen deficiency.

OBJECTIVE

To determine whether and to what extent selective estrogen receptor modulators are an effective and safe therapy in men with obesity-related functional androgen deficiency.

MATERIALS AND METHODS

A thorough search of PubMed, Web of Science, Scopus, and Cochrane Library databases was performed to identify studies comparing testosterone levels before and after treatment. Mean differences with 95% coefficient intervals were combined using random effects models. Funnel plot, Egger's test, and trim-and-fill analysis were used to assess publication bias.

RESULTS

Seven studies met the inclusion criteria providing information on 292 men with obesity-related functional androgen deficiency treated with clomiphene citrate (12.5-50 mg daily) or enclomiphene citrate (12.5-25 mg daily) for 1.5-4 months. The pooled estimates indicated a significant increase in testosterone levels both with clomiphene (mean difference: 11.56 nmol/L; 95% coefficient interval: 9.68, 13.43; I2  = 69%, pfor heterogeneity  = 0.01) and enclomiphene citrate (mean difference: 7.50 nmol/L; 95% coefficient interval: 6.52, 8.48; I2  = 4%, pfor heterogeneity  = 0.37). After the exclusion of one study on severely obese men, who exhibited the highest response rate to clomiphene citrate, the heterogeneity disappeared (mean difference: 10.27 nmol/L; 95% coefficient interval: 9.39, 11.16; I2  = 0%, pfor heterogeneity  = 0.66). No publication bias was revealed by Egger's test and trim-and-fill analysis. No treatment-related unexpected findings regarding safety profile were registered.

DISCUSSION AND CONCLUSION

Treatment with clomiphene citrate and enclomiphene citrate may be an effective and safe alternative to testosterone replacement therapy in men with obesity-related functional androgen deficiency. Further long-term studies are warranted to define clinical reflections of the selective estrogen receptor modulators-induced increase in testosterone levels and to better clarify the safety profile.

Adverse effects and potential benefits among selective androgen receptor modulators users: a cross-sectional survey

Selective androgen receptor modulators (SARMs) are a class of androgen receptor ligands that bind androgen receptors and display tissue selective activation of androgenic signaling. SARMs have selective anabolic effects on muscle and bone, and were originally synthesized for treatment of muscle wasting conditions, osteoporosis, breast cancer. To date, no SARM has been clinically approved and little is known about the beneficial effects and other adverse effects on users. We examined the adverse effects and potential benefits of SARMs amongst users. We performed an internet survey assessing the demographics of users via a 32-question survey. Using reddit as a platform, we distributed the survey through various subreddits that included potential SARMs users. Out of the 520 responses, 343 participants admitted having used SARMs. Most were males (98.5%), between the ages of 18-29 (72.3%). More than 90% of users acquired SARMs via the internet and did not consult with a physician. More than half of SARMs users experienced side effects including mood swings, decreased testicular size, and acne. More than 90% of men reported increased muscle mass and were satisfied with their SARMs usage. Despite having seemingly positive effects, more than 50% of SARMs users report significant adverse effects. Chi square was the main method of statistical analysis. Future studies should focus on comprehensive reproductive evaluation of men using SARMs.

Male Idiopathic Hypogonadotropic Hypogonadism: Serum Insulin-like Growth Factor-1 and Oestradiol Levels

Background

Idiopathic hypogonadotropic hypogonadism (IHH) is a form of male infertility caused by a congenital defect in the secretion or action of gonadotropin-releasing hormone from the hypothalamus. Oestradiol emerged as the main sex steroid in the regulation of the hypothalamic-pituitary-testicular axis, reproductive function and growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis in men. Moreover, GH/IGF-1 axis has been suggested to play a role in IHH.

Aims

This study evaluated serum IGF-1 in IHH men and controls. Furthermore, we evaluated the association between serum total oestradiol (TE2) and IGF-1 levels in patients and controls. Parameters including age, body mass index and fertility history were analysed.

Settings and Design

This prospective study was conducted at the Royan institute.

Materials and Methods

In 20 men with IHH and 20 controls, serum IGF-1 levels were estimated using chemiluminescence immunoassay and serum E2 levels were assessed by means of the electrochemiluminescence method.

Statistical Analysis Used

Kolmogorov-Smirnov test, parametric t-test or the Mann-Whitney and the Pearson correlation coefficient were performed. SPSS version 22 was used for the analysis of data.

Results

There was a significant decrease in serum IGF-1 levels in IHH patients compared with controls (145.1 ± 8.9 ng/ml vs. 229.6 ± 7.3 ng/ml P < 0.001, respectively). Furthermore, a significant decrease was observed in TE2 levels in IHH male patients (12.3 ± 2.5 pg/ml) compared with controls (31.9 ± 5.3 pg/ml P < 0.001). A positive correlation was observed between serum IGF-1 and TE2 levels in the total number of participants, suggesting that E2 deficiency in IHH cases can explain the lower levels of serum IGF-1.

Conclusions

These findings suggest that the reduction in IGF-1 levels may be associated with the influence of E2 on the GH/IGF-1 axis, and may confirm the role of the GH/IGF-1 axis in IHH. Further investigations will be required to determine the exact mechanisms by which E2 and IGF-1 affect the reproductive neuroendocrine function.

Comparison of the effect of combined therapy of HCG ampule and letrozole tablet with each method separately on the spermogram parameters in the obese men with idiopathic infertility: a clinical trial

INTRODUCTION

Considering that the use of aromatase inhibitors in the treatment of infertile men is a new approach and obesity in men is one of the factors affecting infertility, we decided to compare the effect of combined therapy of Human chorionic gonadotropin (HCG) and Letrozole and either of the two methods alone on the spermogram parameters in obese men with idiopathic infertility.

MATERIALS AND METHODS

This clinical trial study was performed with the participation of 15 infertile and obese men from 2018 to 2019 in Tabriz (infertility clinics); Patients were randomly divided into three groups; The first group received treatment with Letrozole 2.5 mg daily alone, the second group received treatment with HCG ampoules at a dose of 5000 units twice a week, and the third group received combination therapy with HCG ampoules at a dose of 5000 units twice a week and letrozole tablets at a dose of 2.5 mg daily; The results of testosterone and sperm tests before and after the intervention were evaluated by t-test and linear regression tests in SPSS21 software. A p-value less than 0.05 was considered significant.

RESULTS

There was no statistically significant difference between semen indices and hormones studied before the intervention (P < 0.05), while after the intervention there were statistically significant differences between all variables compared to those before the intervention (P < 0.05); Also, the rate of change in the third group was much more favorable than the other two groups.

CONCLUSION

The combination of HCG ampules with letrozole tablets compared to the use of these drugs alone improved sperm count, sperm motility, and sperm morphology.

The role of the androgen receptor in the pathogenesis of obesity and its utility as a target for obesity treatments

Obesity is associated with hypothalamic-pituitary-testicular axis dysregulation in males. Here, we summarize recent evidence derived from clinical trials and studies in preclinical animal models regarding the role of androgen receptor (AR) signaling in the pathophysiology of males with obesity. We also discuss therapeutic strategies targeting the AR for the treatment of obesity and their limitations and provide insight into the future research necessary to advance this field.

Influence of Fruit and Vegetable Consumption on Antioxidant Status and Semen Quality: A Cross-Sectional Study in Adult Men

The influence of fruit and vegetable consumption on semen quality by reducing oxidative stress is inconsistent. Thus, the association between the consumption of these products, antioxidant status, and semen quality was investigated in 90 men aged 18–40. The consumption of fruit and vegetables was collected using the 3-day food record method. Antioxidant status: total antioxidant capacity in semen (TAC-s) and blood (TAC-b), blood superoxide dismutase (SOD-b), glutathione reductase (GR-b), glutathione peroxidase (GPx-b), catalase (CAT-b) activity, and malondialdehyde concentration in blood (MDA-b) were measured. Sperm concentration, leukocytes in the ejaculate, vitality, motility, and sperm morphology were examined using computer-aided semen analysis (CASA). The consumption of fruit and vegetables was positively correlated with sperm concentration, vitality, motility, TAC-s, TAC-b, and SOD-b activity. The TAC-s and TAC-b were positively related to motility, TAC-s was inversely correlated with sperm tail defects. The SOD-b activity was positively correlated with vitality, motility, sperm morphology, and inversely with sperm tail defects and leukocytes in the ejaculate. Compared to the men in the first quartile of fruit and vegetable consumption (<318 g/day), those in the highest quartile (>734 g/day) had the highest sperm concentration, vitality, motility, TAC-s, TAC-b, GPx-b activity, and the lowest MDA-b concentration (based on multivariate regression models). A high consumption of fruit and vegetables may positively influence selected sperm quality parameters by improving the antioxidant status of semen and blood.

Effectiveness of Pharmacological Intervention Among Men with Infertility: A Systematic Review and Network Meta-Analysis

Background. Infertility is an emerging health issue for men. Comparative efficacy of different pharmacological interventions on male infertility is not clear. The aim of this review is to investigate the efficacy of various pharmacological interventions among men with idiopathic male infertility. All randomized control trials evaluating the effectuality of interventions on male infertility were included for network meta-analysis (NMA) from inception to 31 April 2020, systematically performed using STATA through the random effect model. The protocol was registered at PROSPERO (CRD42020152891). Results. The outcomes of interest were semen and hormonal parameters. Treatment effects (p < 0.05) were estimated through WMD at the confidence interval of 95%. Upon applying exclusion criteria, n=28 RCTs were found eligible for NMA. Results from NMA indicated that consumption of supplements increases sperm concentration levels [6.26, 95% CI 3.32, 9.21] in comparison to SERMs [4.97, 95% CI 1.61, 8.32], hormones [4.14, 95% CI 1.83, 6.46], and vitamins [0.15, 95% CI -20.86, 21.15)] with placebo, whereas the use of SERMs increased percentage sperm motility [6.69, 95% CI 2.38, 10.99] in comparison to supplements [6.46, 95% CI 2.57, 10.06], hormones [3.47, 95% CI 0.40, 6.54], and vitamins [-1.24, 95% CI -11.84, 9.43] with placebo. Consumption of hormones increased the sperm morphology [3.71, 95% CI, 1.34, 6.07] in contrast to supplements [2.22, 95% CI 0.12, 4.55], SERMs [2.21, 95% CI -0.78, 5.20], and vitamins [0.51, 95% CI -3.60, 4.62] with placebo. Supplements boosted the total testosterone levels [2.70, 95% CI 1.34, 4.07] in comparison to SERMs [1.83, 95% CI 1.16, 2.50], hormones [0.40, 95% CI -0.49, 1.29], and vitamins [-0.70, 95% CI -6.71, 5.31] with placebo. SERMs increase the serum FSH levels [3.63, 95% CI 1.48, 5.79] better than hormones [1.29, 95% CI -0.79, 3.36], vitamins [0.03, 95% CI -2.69, 2.76], and supplements [-4.45, 95% CI -7.15, -1.76] in comparison with placebo. Conclusion. This review establishes that all interventions had a significantly positive effect on male infertility. Statistically significant increased sperm parameters were noted in combinations of zinc sulfate (220 mg BID), clomiphene citrate (50 mg BID), and testosterone undecanoate and CoQ10; tamoxifen citrate and FSH were shown to improve the hormonal profile in infertile males.

Prolonged use of letrozole causes morphological changes on gonads in Galea spixii

Letrozole is used as a therapeutic agent in reproductive disorders caused by high estrogen levels. Letrozole inhibits cytochrome P450 aromatase and reduces estrogen levels. However, the effects of long-term use on reproductive traits are unknown. The aim of this study was to evaluate the prolonged use of letrozole in the gonads of rodents (Spix's yellow-toothed cavy; Galea spixii). Forty-eight rodents (24 males and 24 females) were randomly divided into the treated and control groups. Letrozole administration started at 15 days of age and continued weekly until 30, 45, 90, and 120 days of age. The body, testis, and ovary weights were analyzed, as well as the morphological progression of spermatogenesis and folliculogenesis. Macroscopically, body weight gain and gonads weight were increased in the letrozole group. Microscopically, the ovaries of treated females showed stratified epithelium and a cellular disorder of the tunica albuginea. In the testes of treated males, the development of seminiferous tubules was delayed and sperm was absent. The collective findings indicate that the prolonged use of letrozole alters secondary sexual characteristics, and causes weight gain, reproductive changes, and male infertility.

Are sex discordant outcomes in COVID-19 related to sex hormones?

COVID-19 has a clear sex disparity in clinical outcome. Globally, infection rates between men and women are similar; however, men are more likely to have more severe disease and are more likely to die. The causes for this disparity are currently under investigation and are most likely multifactorial. Sex hormones play an important role in the immune response with estrogen seen as immune boosting and testosterone as immunosuppressing. Additionally, an important protease involved in viral entry, TMPRSS2, is regulated by androgens. Many observational and prospective studies are ongoing or initiating to further examine the role of sex hormones in SARS-CoV-2 infection and if modulation of them is a realistic treatment option.

Baseline Gonadotropin Levels and Testosterone Response in Hypogonadal Men Treated With Clomiphene Citrate

OBJECTIVE

To investigate the role of baseline gonadotropins in predicting the biochemical response to clomiphene citrate (CC) treatment.

METHODS

We conducted a retrospective review of data from hypogonadal men treated with CC in 2 high-volume fertility centers between 2013 and 2018. Patient age, body mass index, and baseline hormones (follicle stimulating hormone [FSH], luteinizing hormone [LH], and total testosterone [TT]) were obtained. Response to treatment was measured as changes in TT levels within 6 months of initiating CC treatment. Linear regression models adjusted for age, body mass index, and time on CC therapy were fitted to assess the associations between baseline LH and FSH levels with treatment response.

RESULTS

A total of 332 men with mean ± standard deviation age of 36.2 ± 8.2 years were included. Median time to initial follow-up was 6 weeks (25th-75th interquartile range [IQR]: 4-9 weeks). TT levels increased significantly on CC treatment (mean change: 329.2 ng/dL, 95% CI: 307.4-351.0) with 73% of men having at least 200 ng/dL increase over baseline TT levels. In univariable linear regression models, only age was significantly associated with TT response. Neither the baseline LH nor FSH significantly predicted TT response in linear regression models.

CONCLUSION

CC treatment results in significant increases in testosterone levels in most men. Baseline gonadotropins are not strong predictors for treatment response to CC. Adequate biochemical response with CC trial can be expected in most patients with normal or slightly elevated baseline gonadotropin levels.

Treatment of Estrogen Levels in the Management of Hypogonadism: An Anonymous Survey of ISSM Members

OBJECTIVE

To assess the variability in management of estrogen levels in men treated with testosterone therapy (TTh). With the significant increase in the last 2 decades in the treatment of hypogonadism and the use of TTh, detailed guidelines for the management of estrogen levels are necessary.¹ MATERIALS AND METHODS: An anonymous survey was electronically distributed to the membership of the International Society for Sexual Medicine including questions on demographics, symptoms, and their approach to management of estrogen in patients on TTh. Chi-square test was used to determine associations.

RESULTS

The response rate was 22.5% (489/2168). A total 62.4% of respondents indicated that they check serum estrogen at initial evaluation, but only 54.7% monitor levels in patients on TTh (P = .02). Fellowship-trained and North American respondents were more likely to monitor patients (P < .05). A total of 69.4%, 47.7%, and 14.4% respondents prescribe antiestrogenic medications in symptomatic patients with elevated estrogen levels, for asymptomatic-elevated estrogen levels, and prophylactically, respectively. Academic respondents were more likely to prescribe an antiestrogen medication to symptomatic patients and prophylactically (P < .05). Anastrozole was the most common medication prescribed for symptomatic hyperestrogenemia (62.3%), but starting doses varied significantly, from 1 mg weekly to 1 mg daily.

CONCLUSION

Approximately 50% of practitioners treating men with TTh monitor estrogen levels. Symptoms play a role in prescribing patterns and significant variability in aromatase inhibitors regimens exists. Increased monitoring of estrogen levels in men on TTh will facilitate an understanding of the symptoms, effects of high and low estrogen levels, and aid in standardization of research and therapy.