Endocrine effects of testosterone undecanoate as a supplementary treatment to menopausal gonadotropins or tamoxifen citrate in idiopathic oligozoospermia

Efficacy and safety of letrozole or anastrozole in the treatment of male infertility with low testosterone-estradiol ratio: a meta-analysis and systematic review

BACKGROUND

Aromatase inhibitors (AIs) have been used to treat male infertility for decades. However, due to the lack of large-scale randomized controlled studies and basic research, the efficacy and safety of AIs in the treatment of male infertility remain controversial. Therefore, it is necessary to conduct an evidence-based preliminary evaluation of the existing clinical trials of AIs in the treatment of male infertility.

METHOD

A comprehensive literature search were performed in PubMed, Embase, Cochrane, CNKI, VIP, CBM, and Wanfang databases through August 2021 for all studies. We conducted a systematic review with meta-analysis of the all available studies reporting sperm conventional parameters, gonadotropin and testosterone levels, and/or the pregnancy rate.

RESULTS

A total of 10 studies involving 666 patients were included. letrozole (LE) or anastrozole (AZ) administration increased significantly sperm concentration, total sperm count, and serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T) levels and testosterone to estradiol ratio (T/E2), but E2 levels were significantly reduced compared with baseline values. Compared with the control group, which included selective estrogen receptor modulators (SEMRs) or HCG, LE or AZ did not have any significant effect on sperm concentration, motility and morphology, except that AIs had less effect on sperm motility than the control group (WMD: -2.55; 95% CI:-4.11 to-1.00; P = 0.001).

CONCLUSION

AIs may be effective in the treatment of male infertility. For male infertile patients planning assisted reproduction, discontinuation of AIs for 2-7 days prior to sperm retrieval may increase the success rate of fertilization. Further studies with larger sample sizes are needed to validate these findings. This article is protected by copyright. All rights reserved.

Effects of the selective estrogen receptor modulators for the treatment of male infertility: a systematic review and meta-analysis

Background: Selective estrogen receptor modulators (SERMs) represent a poorly investigated class of drugs for the treatment of male infertility. The aim of this study was to assess the effects of SERMs on conventional sperm parameters, serum gonadotropin and testosterone levels, and pregnancy rate in patients with idiopathic infertility. Methods: The authors performed a comprehensive systematic review with meta-analysis of all available controlled and not-controlled studies of the literature reporting sperm conventional parameters, gonadotropin and testosterone levels, and/or the pregnancy rate following SERM administration in normogonadotropic patients with idiopathic oligozoospermia. Results: From the 418 papers retrieved, 16 controlled and not-controlled trials were lastly included. SERM administration increased significantly sperm concentration, total sperm count, and serum luteinizing hormone, follicle-stimulating hormone, and total testosterone levels compared with baseline values. In contrast, SERMs did not have any significant effect on sperm concentration and progressive and total motility, but improved total sperm count, sperm morphology, and increased the pregnancy rate compared to the control group, which included studies done with placebo or other treatments. Conclusions: The results of this meta-analysis suggest that SERMs may be effective in the treatment of infertile patients with idiopathic infertility. However, the paucity of data does not allow to draw a definitive conclusion.

Environmental chromium from the tannery industry induces altered reproductive endpoints in the wild female small Indian mongoose (Urva auropunctatus)

The populations of wild animals are declining in many parts of the world in response to man-made alterations in the environment. Environmental contamination due to heavy metals discharge from industry may contribute to the decline of wild animal populations by impacting their reproduction, growth, and development. In the leather tanning industry, chromium (Cr) is used as a basic component, but it is a potent toxicant that can affect many of the physiological functions of animals. In the current study, we investigated the reproductive toxicity of industrial Cr in female small Indian mongooses inhabiting a tannery area. Adult female specimens were live trapped from February 2015 to January 2016. Blood and other body tissues (ovaries, kidneys and liver) of the captured specimens were collected along with soil and water samples from the environment for analysis. The Cr concentrations were found significantly ( p < 0.0001) increased compared to control in the environment, blood, and all body tissues of the animals. Estradiol and progesterone levels were found to be significantly decreased in comparison with control ( p < 0.0001), along with reduced ovarian weights, while follicle stimulating hormone (FSH) and luteinizing hormone levels were found significantly ( p < 0.0001) elevated. Light microscopy revealed significantly decreased in comparison with control ovarian follicle numbers ( p < 0.0001) and diameters, vacuolization of the oocytes, and a significantly higher percentage of atretic follicles inside the ovary. We conclude that Cr discharged from the tanneries is absorbed by the exposed female small Indian mongoose, leading to ovarian dysfunction with potential impairment of reproductive function.

More attention should be paid to the treatment of male infertility with drugs--testosterone: to use it or not?

Testosterone replacement is strictly contraindicated for the treatment of male infertility’ was the advanced view from the ‘2013 European Association of Urology (EAU) guidelines on male infertility’, and this view brings extensive concern and questions. Although sufficient numbers of well-performed and controlled clinical trials that provide evidence supporting drug treatment of male infertility are not available at present, the opportunity to prove that these drugs are effective should not be prevented, and rigorous examination of drug therapy should be encouraged and strengthened. Therefore, I believe the above conclusion in the EAU guidelines is poorly conceived.

Persistent hexavalent chromium exposure impaired the pubertal development and ovarian histoarchitecture in wistar rat offspring

Hexavalent chromium (CrVI) is a highly toxic metal and a major environmental pollutant. Several studies indicate that CrVI exposure adversely affects reproductive function. We reported that maternal Cr exposure resulted in Cr accumulation in the reproductive organs of female offsprings. CrVI can cross the placental barrier and also can be passed through breastfeeding. The present investigation aimed to determine the persistent (in utero through puberal period) CrVI exposure-induced toxic effects on the reproductive functions of mother and the offspring. Induction of oxidative stress is one of the plausible mechanisms behind Cr-induced cellular deteriorations. Mother rats exposed to CrVI showed reduced reproductive outcome, while the offsprings showed higher accumulation of Cr in ovary, altered steroid, and peptide hormones. Specific activities of antioxidant enzymes were decreased and associated with increased levels of H2 O2 , and lipid peroxidation. CrVI exposure also damaged the ovarian histoarchitecture in various age groups studied. CrVI exposure also delayed the sexual maturation. Results from the present investigation suggest that CrVI exposure from in utero through puberal period significantly damaged the pubertal development through altered antioxidants, anemia, and altered hormone levels. These changes were associated with damaged ovarian histoarchitecture and extended estrous cycle in developing Wistar rats.

Follicle-stimulating hormone treatment in normogonadotropic infertile men

Several empirical treatments have been proposed to treat idiopathic infertility in men, including follicle-stimulating hormone (FSH). FSH administration is effective in patients with hypogonadotropic hypogonadism, which suggests it might be useful in patients with oligozoospermia who have normal FSH levels. Indeed, many studies have evaluated the efficacy of FSH administration in these patients, several of which have shown improvements in sperm parameters. By contrast, other studies have not reported any significant effect of FSH administration on conventional sperm parameters, although some of have reported the normalization of spermatozoon ultrastructural morphology, as well as reductions in DNA fragmentation, production of reactive oxygen species and aneuploidy. Contemporary studies suggest that the response to FSH treatment in oligozoospermic patients might, at least partially, reflect polymorphisms of the FSH receptor gene. Thus, FSH administration in oligozoospermic men with normal serum FSH levels might be efficacious only in selected patients. For this reason, additional studies are needed to determine the predictive factors and clinical conditions that can be used to identify patients who could benefit from FSH treatment.

Changes in hormonal profile and seminal parameters with use of aromatase inhibitors in management of infertile men with low testosterone to estradiol ratios

OBJECTIVE

To compare the effects of 2.5 mg letrozole with those of 1 mg anastrazole daily on the hormonal and semen profiles of a subset of infertile men with low T/E(2) ratios.

DESIGN

Prospective, nonrandomized study.

SETTING

Reproductive medicine clinic.

PATIENT(S)

The study group consisted of 29 infertile men with a low serum T/E(2) ratio (<10).

INTERVENTION(S)

Patients were divided into two groups. Group A included 15 patients treated with 2.5 mg letrozole orally once daily for 6 months, and Group B consisted of 14 patients treated with 1 mg anastrazole orally every day for 6 months.

MAIN OUTCOME MEASURE(S)

Hormonal evaluation included measurement of serum FSH, LH, PRL, T, and E(2). In all sperm analyses pretreatment and posttreatment total motile sperm counts (ejaculate volume × concentration × motile fraction) were evaluated.

RESULT(S)

The use of aromatase inhibitors (either letrozole or anastrazole) in cases of infertile men with low T/E(2) ratios improved both hormonal and semen parameters.

CONCLUSION(S)

This study suggests that some men with severe oligospermia, low T levels, and normal gonadotropin concentration may have a treatable endocrinopathy.

An empiric treatment for idiopathic oligozoospermia revisited: a 20-year investigative saga

A series of studies aiming at introducing an effective treatment for idiopathic oligozoospermia was conducted in a step-wise fashion spanning over a 20-year period. The concept was that co-administration of an accessory gland-stimulating androgen, testosterone undecanoate (40 mg t.i.d.) and the FSH raising anti-oestrogen tamoxifen citrate (10 mg b.i.d.) may improve sperm parameters. A prerequisite for such an effect was the demonstration that testosterone undecanoate had no suppressing action on pituitary-testicular axis. In this context, initial studies demonstrated no change in basal or stimulated gonadotrophin and testosterone secretion in short- or long-term protocols. Two subsequent trials with this combination showed a marked improvement of sperm parameters and pregnancy incidence, with a seasonal variation noted in response to treatment, this being higher during the cold seasons of autumn and winter. Regarding the mechanism of testosterone undecanoate's action, a recent study from our unit showed that its administration resulted in a marked rise of serum DHT levels. Because this steroid is an epididymal function promoter, it appears that its contribution in the combination is mediated mainly through its DHT raising effect. By and large, this empiric approach for the treatment of idiopathic oligozoospermia was satisfactorily documented after a 20-year investigative saga.

Oxidative stress and antioxidants for idiopathic oligoasthenoteratospermia: Is it justified?

Oxidative stress contributes to defective spermatogenesis and the poor quality of sperm associated with idiopathic male factor infertility. The aim of this study was to review the current literature on the effects of various types of antioxidant supplements in patients to improve fertilization and pregnancy rates in subfertile males with idiopathic oligoasthenoteratozoospermia (iOAT). Review of recent publications through PubMed and the Cochrane database. Oxidative stress is implicated in impaired spermatogenesis leading to the poor semen parameters and increased DNA damage and apoptosis in iOAT. Strategies to modulate the level of oxidative stress within the male reproductive tract include the use of oral antioxidant compounds to reinforce the body's defence against oxidative damage. In our evaluation, carnitines were considered the most established pharmacotherapeutic agent to treat iOAT, as evidence and data concerning carnitine supplementation have been shown to be most consistent and relevant to the population of interest. Other therapies, such as combined vitamin E and C therapy, are still considered controversial as vitamin C can act as a pro-oxidant in certain instances and the results of randomized controlled trials have failed to show significant benefit to sperm parameters and pregnancy rates. There is a need for further investigation with randomized controlled studies to confirm the efficacy and safety of antioxidant supplementation in the medical treatment of idiopathic male infertility as well as the need to determine the dosage required to improve semen parameters, fertilization rates and pregnancy outcomes in iOAT.

Testosterone undecanoate in the functional compartments of the male reproductive tract

Background

Assessment of testosterone undecanoate’s (TU) presence in the functional compartments of the male reproductive tract has never been performed despite the evidence that its documented beneficial effect in male infertility might be mediated through an epididymal action and this study was set to examine this possibility.

Materials and methods

In 18 normozoospermic volunteers TU has been administered (40 mg t.i.d.) for 6 days with serum measurements of TU, total testosterone (T), DHT, E2, SHBG, FSH, LH, and PRL before and at the end of medication. Steroid hormones (T, E2, and TU) were also assayed in seminal plasma. In a selected group of 7 men with previously diagnosed non-obstructive azoospermia TU, T, and E2 were assayed in the extracts of testicular biopsy material taken before ICSI and at the end of the same medication.

Results

A marked rise of serum DHT (average 148%, P < 0.001) has been found after treatment, whereas T, E2, FSH, LH, SHBG, and PRL did not significantly change. Measurable amounts of TU were found in the serum of all men but only in 6 cases in seminal plasma (11.1 ± 8.0 ng/mL) and all of them in semen delivered 7–8 h after the last TU capsule was taken. In dilution fluid from testicular tissue extracts, no detectable amounts of TU were found whereas mean values of 92.5 ± 54.3 pg/mL and 43.8 ± 16.3 ng/mL for E2 and T were observed. Positive correlations among TU and E2, T or DHT concentrations were found in serum samples (P < 0.01, 0.02, and 0.002) as well as between E2 and T (P < 0.01), E2 and DHT (P < 0.001), or T and DHT (P < 0.001).

Conclusion

It is concluded that TU was identified and measured for the first time in seminal plasma of a fair percentage (33%) of men on this medication and was associated in all men with a marked rise of DHT concentration, a known epididymal function promoter, in the absence of an effect on pituitary and gonadal activity. On this evidence, it appears that a beneficial effect of TU on epididymal function may be a distinct possibility.

Effectiveness of combined tamoxifen citrate and testosterone undecanoate treatment in men with idiopathic oligozoospermia

OBJECTIVE

To assess the effect of treatment with a combination of the antiestrogen tamoxifen citrate and the androgen testosterone undecanoate on sperm variables and pregnancy incidence in men with idiopathic oligozoospermia and couple subfertility.

DESIGN

Prospective, randomized, placebo-controlled trial.

SETTING

Clinical research in a tertiary care academic hospital.

PATIENT(S)

Two hundred twelve men with idiopathic oligozoospermia and 82 normozoospermic men with female factor subfertility.

INTERVENTION(S)

Oligozoospermic patients were randomly assigned to two treatment groups with tamoxifen citrate, 20 mg/d, and testosterone undecanoate, 120 mg/d (n = 106) or placebo treatment (n = 106) for 6 months. Normozoospermic men were followed for the same period. Couple counseling was part of the intervention in all groups.

MAIN OUTCOME MEASURE(S)

Pregnancy incidence and sperm characteristics after 3 and 6 months on medication and 3 months after the end of the trial.

RESULT(S)

In the active treatment group, total sperm count (median [25th, 75th percentile], 27.1 x 10(6) cells/mL [9.4, 54.0 x 10(6) cells/mL] at baseline and 61.5 x 10(6) cells/mL [28.2, 119.6 x 10(6) cells/mL] at 6 months), progressive motility (mean [+/-SD], 29.7% +/- 12.0% at baseline and 41.6% +/- 13.1% at 6 months), and normal morphology (mean, 41.2% +/- 14.0% at baseline and 56.6% +/- 11.5% at 6 months) were noted. No marked changes were observed in placebo recipients or normozoospermic men. The incidence of spontaneous pregnancy was 33.9% in the active treatment group and 10.3% in the placebo group (36 vs. 11 pregnancies), with a relative risk of 3.195 (95% CI, 2.615 to 3.765).

CONCLUSION(S)

Treatment with tamoxifen citrate and testosterone undecanoate improved sperm variables and led to a higher incidence of pregnancy in couples with subfertility related to idiopathic oligozoospermia.

Assessment of Sertoli cell functional reserve and its relationship to sperm parameters

Sertoli cell functional reserve was assessed in normozoospermic men and oligozoospermic patients and its prognostic potential was evaluated for patient selection and treatment. For the first objective, three groups of normo-follicle-stimulating hormone (FSH)/normozoospermic fertile men (n:12), normo-FSH/oligozoospermic (n:21) and hyper-FSH/oligozoospermic subfertile men participated in the study whereas for the second objective 24 normo-FSH oligozoospermic patients volunteered for a pilot therapeutic trial. For the first part, high purity (hp) FSH (225 i.u., i.m.), human chorionic gonadotropin (hCG) (1500 i.u., i.m.) or their combination was given separately at weekly intervals, with samplings at 0, 3, 24 and 48 h. For the pilot trial, rec-FSH (150 i.u./48 h, i.m.) or placebo were prescribed for 6 months. The main outcome measures for the study were inhibin-B (inh-B), insulin-like growth factor (IGF)-I, testosterone and oestradiol concentrations and the main sperm parameters. Bolus administration of hp-FSH or hp-FSH/hCG combination in normozoospermic men resulted in a significant rise of inh-B in normozoospermic men (mean +/- SD, basal: 183.8+/-24.2 pg/mL in hp-FSH and 175.2+/-23.5 in hp-FSH/hCG treatment; 48 h: 256.1+/-34.2 and 246.3+/-19.0, respectively, p<0.001 for both). In oligozoospermic groups basal inh-B concentration was lower than in normozoospermic men (normo-FSH: 117.4+/-16.5, hyper-FSH: 81.2+/-19.8, p<0.001 for both) with a post-stimulation increase noted only in normo-FSH patients (hp-FSH 24-h: 132.8+/-19.7, p<0.01; hp-FSH/hCG 0 min: 105.7+/-20.1, 24-h: 119.5+/-20.6, p<0.05). Total sperm number and progressive motility showed significant improvements (p<0.05 for both) after 6 months of rec-FSH treatment in the group of patients with a satisfactory response to hp-FSH stimulation. In conclusion, the basal and reserve activity of Sertoli cells, as judged by inh-B secretion, was higher in normozoospermic than in dyspermic men, with a better therapeutic outcome noted in those patients with an adequate response to hp-FSH stimulation.

Present and future therapeutic strategies for idiopathic oligozoospermia

The effectiveness of medical treatment for idiopathic oligozoospermia (IO) has been at best doubtful until now and a logical consequence of this unsatisfactory situation has been the partial displacement of this approach by assisted reproduction techniques. This state of affairs has resulted from insufficient investigation, inappropriately designed clinical trials and consistent disregard for the principles of evidence-based medicine. Protocol-related shortcomings and wrong interpretation of the data available have also been some of the all too frequent problems encountered in this therapeutic approach. In this rather misty situation, it appears that, of the therapeutic agents used so far, follicle stimulating hormone (FSH) (mainly FSH-secretagogues) may exert some beneficial effects on a number of biological endpoints related to spermatogenesis and sperm maturation. The short and medium term prospects of medical treatment for IO rest mainly with improvement of investigative procedures to a higher degree of sophistication, with emphasis placed on identifying the causes rather than the results of dysfunction so that a better selection of candidates can be made. Moreover, the introduction of prognostic indices for evaluation of the beneficial effects of a therapeutic agent may be of paramount importance. Finally, a better assessment of the preparations available and, possibly, the introduction of new more specific agents may also be an important step forward in this field. This type of large-scale effort should not be left to individual investigators or special centres working independently, but it may come under the auspices of a central regulating agency so that undisputed results from large, multicentre and uniform studies might be obtained, if medical treatment is to remain a good option. In this context, it may also be emphasized that andrology's main task should always be to treat the male with the problem rather than his healthy female partner, whenever this is possible.

Effect of chronic administration of Tamoxifen on fertility in male bonnet monkeys (Macaca radiata)

Administration of Tamoxifen via the Alzet pump at a rate of 50 micrograms hr-1 for 90 days in the adult male bonnet monkeys Macaca radiata had no effect on the serum testosterone concentration determined at 10 AM and 10 PM as well as total sperm count determined at 15-day intervals over a period of 260 days. However, a significant reduction in sperm motility was observed beyond 90 days up until the 225th day. Breeding studies conducted from day 90 to 260 revealed that these males were infertile.

The combination of testosterone undecanoate with tamoxifen citrate enhances the effects of each agent given independently on seminal parameters in men with idiopathic oligozoospermia

OBJECTIVE

To evaluate the effects of combined tamoxifen citrate and T undecanoate treatment on seminal parameters in men with idiopathic oligozoospermia.

DESIGN

Prospective randomized clinical study.

SETTING

A state hospital tertiary clinic.

PATIENT(S)

Eighty oligozoospermic men were included in the protocol.

INTERVENTION(S)

Patients were randomized to receive placebo, T undecanoate (40 mg three times per day), tamoxifen citrate (10 mg two times per day), or T undecanoate plus tamoxifen citrate.

RESULT(S)

Tamoxifen citrate plus T undecanoate treatment produced a satisfactory improvement of total sperm number, motility, and functional sperm fraction after 3 and 6 months. Comparisons with other active treatment groups showed significantly higher increment values for motility and functional fraction, whereas aniline, acrosine, and free L-carnitine also were markedly better in the combination treatment group.

CONCLUSION(S)

These results indicate that the combination of tamoxifen citrate with T undecanoate not only improves significantly important seminal parameters but also compares favorably with the single treatments used. Therefore, this combination deserves a place as a first line of treatment in idiopathic oligozoospermia.