Treatment of Hypogonadism: Current and Future Therapies

The complex relation between obstructive sleep apnoea syndrome, hypogonadism and testosterone replacement therapy

Obstructive sleep apnoea syndrome (OSAS) is an under-recognized medical disease. The main risk factors for OSAS are male sex, older age, obesity, and metabolic syndrome, that are also associated with male hypogonadism (MH). Therefore, obesity has been classically identified as the most evident link between OSAS and MH. However, OSAS is per se linked to the development of MH by a combined effect of hypoxia, increased night-time awakenings, reduced sleep efficiency and fragmented sleep. Similarly, MH might represent a risk factor for OSAS, mainly related to sleep disturbances that are frequently associated with low testosterone. Data on testosterone replacement therapy (TRT) in patients with OSAS are limited. Nevertheless, TRT is generally contraindicated by guidelines in the presence of untreated or severe OSAS. TRT might in fact worse OSAS symptoms in different ways. Furthermore, OSAS has been proposed to be a risk factor for secondary polycythaemia and TRT might exacerbate polycythaemia. Therefore, TRT in hypogonadal men affected by untreated OSAS or severe OSAS should be considered with caution and in a personalised way. Nevertheless, the type and dosage of TRT should be considered, as short-term high-dose TRT might worsen OSAS, whereas long-term lower doses could eventually determine a clinical improvement of symptoms of OSAS. Here we reviewed the data on the association between OSAS, MH and TRT, including the opportunity of assessment of patients who develop signs and symptoms of OSAS during TRT by polysomnography.

Testosterone Therapy is Associated With Depression, Suicidality, and Intentional Self-Harm: Analysis of a National Federated Database

BACKGROUND

Long-term use of testosterone can be associated with mood destabilizing effects. Most studies investigating psychiatric complications of anabolic steroids have used small samples, but a comprehensive assessment of the risk of developing mental health disorders after testosterone use has not been performed at the population level.

AIM

To determine whether testosterone therapy is associated with major depressive disorder or suicide attempts in men.

METHODS

We conducted a retrospective cohort study of 70.3 million electronic health records collected from 46 healthcare organizations encompassing flagship hospitals, satellite hospitals, and outpatient clinics since 2008 to determine whether testosterone use is associated with major depressive disorder and suicide attempts in a large population. We included men 18 or older who either used testosterone or did not, defined by reported use, insurance claim, or prescription use of testosterone documented in the electronic health record. We propensity-score matched by age, race, ethnicity, obesity, and alcohol-related disorder. Additionally, a sub-group analysis was performed in testosterone deficient (<300 ng/dL) men comparing those with TD on testosterone therapy to a control group of men with TD who are not using testosterone.

OUTCOMES

We determined measures of association with a new diagnosis of major depressive disorder and suicide attempt or intentional self-harm following testosterone use within 5 years.

RESULTS

A total of 263,579 men who used testosterone and 17,838,316 men who did not were included in the analysis. Testosterone use was independently associated with both Major Depressive Disorder (OR 1.99, 95% CI 1.94-2.04, P < .0001) and Suicide Attempt/Intentional Self-Harm (OR 1.52, 95% CI 1.40-1.65, P < .0001). Results remained significant in testosterone deficient sub-group analysis.

CLINICAL IMPLICATIONS

Men who use testosterone should be screened for and counseled about risks of depression and suicidality.

STRENGTHS AND LIMITATIONS

Strengths of this study include a large sample size, the ability to account for chronology of diagnoses, the use of propensity score matching to control for potentially confounding variables, and the consistency of results with sub-group analyses. Limitations include the potential for incorrect coding within the electronic health record, a lack of granular information regarding testosterone therapy adherence, the possibility that unrecorded testosterone or anabolic steroid use were prevalent but not captured within the control group, and a lack of data regarding testosterone withdrawal.

CONCLUSION

Testosterone use is independently associated with new-onset mental health disorders. Future studies are necessary to elucidate the role that androgen withdrawal plays and whether a causal relationship exists. Nackeeran S, Patel MS, Nallakumar DT, et al. Testosterone Therapy is Associated With Depression, Suicidality, and Intentional Self-Harm: Analysis of a National Federated Database. J Sex Med 2022;19:933-939.

Effects of testosterone and exercise training on bone microstructure of rats

Background and Aim:

Male hypogonadism results from failure to produce physiological levels of testosterone. Testosterone in men is essential in masculine development, sperm production, and adult man’s health. Osteoporosis is one of the consequences of hypogonadism. Regular physical exercise and exogenous testosterone administration are frequently used to prevent or treat this condition. This study aimed to understand the effects of lifelong exercise training and testosterone levels (isolated and together) in the main bone structure parameters.

Materials and Methods:

A total of 24 rats were used and randomly divided into four groups: Control group (CG; n=6), exercised group (EG, n=6), testosterone group (TG, n=6), and testosterone EG (TEG, n=6). A micro-computed tomography equipment was used to evaluate 15 bone parameters.

Results:

Both factors (exercise training and testosterone) seem to improve the bone resistance and microstructure, although in different bone characteristics. Testosterone influenced trabecular structure parameters, namely, connectivity density, trabecular number, and trabecular space. The exercise promoted alterations in bone structure as well, although, in most cases, in different bone structure parameters as bone mineral density and medullar mineral density.

Conclusion:

Overall, exercise and testosterone therapy seems to have a synergistic contribution to the general bone structure and resistance. Further studies are warranted, comparing different individual factors, as gender, lifestyle, or testosterone protocols, to constantly improve the medical management of hypogonadism (and osteoporosis).

Zinc and Shell Flour as Innovative Natural Aromatase Blocker to Increase Testosterone Concentration

The hormone testosterone is essential in various biological processes, including reproductive function so its presence in the body must remain stable. Low concentrations of testosterone can affect secondary traits and libido in male animals. Testosterone concentrations are usually increased through hormonal induction, but this will harm long-term administration. The alternative offered in this problem is to give aromatase blockers both in the form of commercial drug injection (letrozole) and natural ingredients (shell powder). Aromatase blockers can inhibit the synthesis of estrogen from testosterone at certain doses that are usually different for each animal, administering aromatase blockers has been shown to increase testosterone concentration, in birds and chickens the administration of aromatase blockers did not have any significant side effects.

Smart design approaches for orally administered lipophilic prodrugs to promote lymphatic transport

Challenges to effective delivery of drugs following oral administration has attracted growing interest over recent decades. Small molecule drugs (<1000 Da) are generally absorbed across the gastrointestinal tract into the portal blood and further transported to the systemic circulation via the liver. This can result in a significant reduction to the oral bioavailability of drugs that are metabolically labile and ultimately lead to ineffective exposure and treatment. Targeting drug delivery to the intestinal lymphatics is attracting increased attention as an alternative route of drug transportation providing multiple benefits. These include bypassing hepatic first-pass metabolism and selectively targeting disease reservoirs residing within the lymphatic system. The particular physicochemical requirements for drugs to be able to access the lymphatics after oral delivery include high lipophilicity (logP>5) and high long-chain triglyceride solubility (> 50 mg/g), properties required to enable drug association with the lipoprotein transport pathway. The majority of small molecule drugs, however, are not this lipophilic and therefore not substantially transported via the intestinal lymph. This has contributed to a growing body of investigation into prodrug approaches to deliver drugs to the lymphatic system by chemical manipulation. Optimised lipophilic prodrugs have the potential to increase lymphatic transport thereby improving oral pharmacokinetics via a reduction in first pass metabolism and may also target of disease-specific reservoirs within the lymphatics. This may provide advantages for current pharmacotherapy approaches for a wide array of pathological conditions, e.g. immune disease, cancer and metabolic disease, and also presents a promising approach for advanced vaccination strategies. In this review, specific emphasis is placed on medicinal chemistry strategies that have been successfully employed to design lipophilic prodrugs to deliberately enable lymphatic transport. Recent progress and opportunities in medicinal chemistry and drug delivery that enable new platforms for efficacious and safe delivery of drugs are critically evaluated.

Insights into the Regulation on Proliferation and Differentiation of Stem Leydig Cells

Male hypogonadism is a clinical syndrome caused by testosterone deficiency. Hypogonadism can be caused by testicular disease (primary hypogonadism) or hypothalamic-pituitary dysfunction (secondary hypogonadism). The present strategy for treating hypogonadism is the administration of exogenous testosterone. But exogenous testosterone is reported to have negative side effects including adverse cardiovascular events and disruption of physiological spermatogenesis probably due to its inability to mimic the physiological circadian rhythm of testosterone secretion in vivo. In recent years, a growing number of articles demonstrated that stem Leydig cells (SLCs) can not only differentiate into functional Leydig cells (LCs) in vivo to replace chemically disrupted LCs, but also secrete testosterone in a physiological pattern. The proliferation and differentiation of SLCs are regulated by various factors. However, the mechanisms involved in regulating the development of SLCs remain to be summarized. Factors involved in the regulation of SLCs can be divided into environmental pollutants, growth factors, cytokine and hormones. Environmental pollutants such as Perfluorooctanoic acid (PFOA) and Triphenyltin (TPT) could suppress SLCs proliferation or differentiation. Growth factors including FGF1, FGF16, NGF and activin A are essential for the maintenance of SLCs self-renewal and differentiation. Interleukin 6 family could inhibit differentiation of SLCs. Among hormones, dexamethasone suppresses SLCs differentiation, while aldosterone suppresses their proliferation. The present review focuses on new progress about factors regulating SLC's proliferation and differentiation which will undoubtedly deepen our insights into SLCs and help make better clinical use of them. Different factors affect on the proliferation and differentiation of stem Leydig cells. Firstly, each rat was intraperitoneally injected EDS so as to deplete Leydig cells from the adult testis. Secondly, the CD51+ or CD90+ cells from the testis of rats are SLCs, and the p75+ cells from human adult testes are human SLCs. These SLCs in the testis start to proliferate and some of them differentiate into LCs. Thirdly, during the SLCs regeneration period, researchers could explore different function of those factors (pollutants, growth factors, cytokines and hormones) towards SLCs.

Compounded bioidentical hormone products, a path forward

OBJECTIVE

To describe the widespread use of compounded bioidentical hormone therapies (cBHT). To define the term clinical utility and present why there is insufficient evidence to support the overall clinical utility of cBHT products. To recommend actions that pharmacists and regulators can take to promote safer cBHT use.

SUMMARY

Nationwide, millions of men and women use cBHT products. Use of these products appears to be increasing year-to-year, according to the limited data reported by the 503 A and 503 B pharmacies that formulate and dispense these products. Although use appears to be widespread, the safety, efficacy, and clinical utility of these products remains unproven. This commentary provides examples of what draws consumers to these products, comparative costs, and formulation challenges. Actions to promote the safe use of cBHT and approaches to begin the study of these products are provided.

CONCLUSION

While significant progress was made via the Drug Supply Chain Security Act in 2013 to improve the safety of compounding practice in general, efforts to further improve the safety and transparency of cBHT dispensing and use must continue, at both the local and national level.

Management of hypopituitarism: a perspective from the Brazilian Society of Endocrinology and Metabolism

Hypopituitarism is a disorder characterized by insufficient secretion of one or more pituitary hormones. New etiologies of hypopituitarism have been recently described, including head trauma, cerebral hemorrhage, and drug-induced hypophysitis. The investigation of patients with these new disorders, in addition to advances in diagnosis and treatment of hypopituitarism, has increased the prevalence of this condition. Pituitary hormone deficiencies can induce significant clinical changes with consequent increased morbidity and mortality rates, while hormone replacement based on current guidelines protects these patients. In this review, we will first discuss the different etiologies of hypopituitarism and then address one by one the clinical aspects, diagnostic evaluation, and therapeutic options for deficiencies of TSH, ACTH, gonadotropin, and GH. Finally, we will detail the hormonal interactions that occur during replacement of pituitary hormones.

Exogenous testosterone replacement therapy versus raising endogenous testosterone levels: current and future prospects

Testosterone replacement therapy is an important treatment option for men with low testosterone and symptomatic hypogonadism. Various formulations of exogenous testosterone replacement therapy exist, including oral, buccal, intramuscular, transdermal, subdermal, and nasal preparations. However, exogenous testosterone replacement therapy is a double-edged sword, posing risks to fertility due to negative feedback mechanisms on the hypothalamic-pituitary-gonadal (HPG) axis, which is the main regulator of testosterone production and spermatogenesis in males. Alternative pharmacologic therapies are being used to increase endogenous testosterone levels while attempting to preserve fertility and function of the HPG axis. These include selective estrogen receptor modulators, gonadotropins, and aromatase inhibitors. This review focuses on overviewing and comparing the currently available methods of exogenous testosterone replacement therapy, alternative treatments to increasing endogenous testosterone, and novel treatments that are currently under investigation to normalize testosterone levels while preserving the function of the HPG axis. In conclusion, reports suggest that, though Testosterone replacement therapy is an important way to restore testosterone levels and reduce symptoms associated with low testosterone, it is often difficult to decide which treatment to select for patients with testosterone deficiency. Several factors need to be considered to decide on optimal therapy option for the patient which include but are not limited to safety, efficacy, cost-effectiveness, dosing flexibility, and side effects. Alternative approaches which aim to improve endogenous testosterone production and preserve fertility are promising but still are at their initial stages of development. Ultimately, patient-centered decision making is paramount to appropriate treatment selection.

Burden of Male Hypogonadism and Major Comorbidities, and the Clinical, Economic, and Humanistic Benefits of Testosterone Therapy: A Narrative Review

Male hypogonadism and major comorbidities such as type 2 diabetes mellitus, obesity, cardiovascular disease, and osteoporosis appear closely connected, forming a vicious cycle that leads to further hypogonadism. This narrative review provides a comprehensive overview of the current literature on the overall burden of male hypogonadism alongside related comorbidities, and how this may be alleviated through testosterone therapy. Observational and clinical data demonstrate that the interaction of male hypogonadism and its related comorbidities is associated with increased mortality, cardiovascular event risk and reduced quality of life. Evidence from epidemiological and registry-based studies shows that this clinical and humanistic burden translates to increased economic burden on health-care systems, through increased physician visits, medical claims, and drug costs. Male hypogonadism can be managed with testosterone therapy, which is intended to normalize testosterone concentrations and thereby reduce both hypogonadism symptoms and risk of comorbidities. Clinical and observational data suggest that in males with hypogonadism, testosterone therapy rapidly and sustainably improves glycemia, reduces risk of progression to diabetes, leads to significantly reduced waist circumference and fat mass, while providing significant positive effects on cardiovascular event risk and bone density. Significant and sustained improvement in patient-reported erectile function, urinary function, and aging male symptoms have also been shown. Economic evaluations have estimated that reduced comorbidity risk following testosterone therapy may lead to cost-savings, with one study estimating yearly inpatient savings of £3732 for treating comorbidities after intervention. A major unmet need exists in the area of male hypogonadism, particularly related to common comorbidities. Options for treatment include testosterone therapy, which has been shown to alleviate the clinical, economic, and humanistic burden associated with these conditions. As the prevalence of male hypogonadism is likely to increase globally, and this condition may be currently underdiagnosed, cost-saving testosterone therapies should be increasingly considered to manage hypogonadism.

Treatment of Men with Central Hypogonadism: Alternatives for Testosterone Replacement Therapy

Central hypogonadism is a clinical condition, characterized by sexual symptoms and low serum testosterone levels, due to an impaired function of the hypothalamus or pituitary gland. Testosterone replacement therapy (TRT) is the standard treatment for hypogonadism, but it has some disadvantages. TRT is not a good option in men wishing to preserve fertility, nor in men with (a high risk of) prostate cancer, polycythemia, thrombophilia and severe cardiovascular disease. In this review, we discuss alternative treatments for central hypogonadism. If reversible causes are present, non-pharmacological interventions can be therapeutic. Gonadotropins are a good alternative to TRT when fertility is desired in the near future though they require frequent injections. Clomiphene citrate and tamoxifen seem to be a safe alternative for the treatment of functional central hypogonadism in men, as several studies reported a significant increase in testosterone levels with these drugs. However, their use is off-label and data supporting the efficacy of clomiphene citrate and tamoxifen on hypogonadal symptoms are insufficient. For this reason, clomiphene citrate and tamoxifen should not be used in routine clinical practice to treat sexual symptoms in men with central hypogonadism.

Use of medicinal doses of zinc as a safe and efficient coadjutant in the treatment of male hypogonadism

Hypogonadism affects an extensive part of the male population, especially among the elderly. The quest for treatment regarding low levels of serum testosterone and male infertility has, therefore, worldwide relevance. Zinc has important biological actions insofar as the male reproductive physiology and endocrine system. In general, a common and safe recommendation for zinc in the treatment of male hypogonadism is 220 mg of zinc sulfate (equivalent to 50 mg of elemental zinc) twice a day, over one to four months. Additionally, it may be further required to extend, both the treatment, dose and daily fractionation of this mineral. Albeit medicinal doses of zinc may increase total testosterone and improve sperm count, the current body of evidence does not suggest broad recommendations regarding the use of zinc for all types of hypogonadism. In many cases, the use of zinc supplements is insufficient, with the use of surgery and drugs being required for an effective treatment.

Tracking research trends and hotspots in sperm DNA fragmentation testing for the evaluation of male infertility: a scientometric analysis

BACKGROUND

This article describes the research trends in sperm DNA fragmentation (SDF) over the past 20 years (1999-2018) using a scientometric approach.

METHODS

A stepwise approach was adopted to retrieve scientometric data (articles per year, authors, affiliations, journals, countries) from Scopus and analyze the publication pattern of SDF with reference to key areas of research in the field of Andrology.

RESULTS

A total of 2121 articles were retrieved related to SDF. Our data revealed an increasing research trend in SDF (n = 33 to n = 173) over the past 20 years (R² = 0.894). Most productive country in publications was the USA (n = 450), while Agarwal A. (n = 129) being the most productive author. Most of the articles in SDF were primarily focused on lifestyle (n = 157), asthenozoospermia (n = 135) and varicocele (130). Mechanistic studies on SDF were published twice as much as prognostic/diagnostic studies, with significant emphasis on oxidative stress. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was the most widely used technique to evaluate SDF. Publications on SDF related to assisted reproductive techniques also showed a linear increasing trend (R² = 0.933).

CONCLUSIONS

Our analysis revealed an increasing trend in SDF publications predominantly investigating lifestyle, asthenozoospermia and varicocele conditions with TUNEL being the most widely used technique. A substantial increase in research is warranted to establish SDF as prognostic/diagnostic parameter to evaluate clinical scenarios and ART outcomes.

Secondary adrenal insufficiency and pituitary dysfunction in oral/transdermal opioid users with non-cancer pain

Objective To evaluate pituitary function, sexual function and quality of life (QoL) in patients on oral or transdermal opioids. Design and methods Cross-sectional study comparing pituitary function, QoL and sexual function in people on long-term opioid therapy (n = 40) vs an age- and sex-matched control group (n = 25). Baseline pituitary function was assessed on blood samples collected prior to 0900 h. Further testing with corticotropin (250 µg IV) and metyrapone (30 mg/kg) stimulation tests was undertaken on participants with serum cortisol <250 nmol/L. Validated questionnaires completed to assess QoL, fatigue and sexual function. Results Secondary adrenal insufficiency (SAI) was identified on the basis of a failed stimulation test in 22.5% of opioid users vs no controls (P = 0.01). Opioid users with SAI had a higher median morphine-equivalent daily dose (MEDD), P = 0.037 - 50% with MEDD >200 mg and 0% with MEDD <60 mg had SAI. Among male participants, testosterone was inversely associated with BMI (P = 0.001) but not opioid use. A non-significant trend to low testosterone <8 nmol/L in male opioid users (11/24 opioid users vs 2/14 control, P = 0.08) suggests a small subgroup with opioid-induced androgen deficiency. Opioid users had greater fatigue, reduced quality of life in all subsections of the SF-36 and impaired sexual function in both males and females (all scores P < 0.001 compared to controls). Conclusion Long-term opioid therapy was associated with dose-related SAI in over 20% of chronic pain patients and is associated with poor quality of life, fatigue and sexual dysfunction. Obesity confounds the interpretation of opioid-induced male androgen deficiency.

Selective Androgen Receptor Modulators: Current Knowledge and Clinical Applications

INTRODUCTION

Selective androgen receptor modulators (SARMs) differentially bind to androgen receptors depending on each SARM's chemical structure. As a result, SARMs result in anabolic cellular activity while avoiding many of the side effects of currently available anabolic steroids. SARMs have been studied in the treatment of breast cancer and cachexia and have also been used as performance-enhancing agents. Here, we evaluate and summarize the current literature on SARMs.

AIM

To present the background, mechanisms, current and potential clinical applications, as well as risks and benefits of SARMs.

METHODS

A literature review was performed in MEDLINE using the terms selective androgen receptor modulator, hypogonadism, cachexia, breast cancer, benign prostatic hyperplasia, libido, and lean muscle mass. Both basic research and clinical studies were included.

MAIN OUTCOME MEASURE

To complete a review of peer-reviewed literature.

RESULTS

Although there are currently no U.S. Food and Drug Agency-approved indications for SARMs, investigators are exploring the potential uses for these compounds. Basic research has focused on the pharmacokinetics and pharmacodynamics of these agents, demonstrating good availability with a paucity of drug interactions. Early clinical studies have demonstrated potential uses for SARMs in the treatment of cancer-related cachexia, benign prostatic hyperplasia (BPH), hypogonadism, and breast cancer, with positive results.

CONCLUSION

SARMs have numerous possible clinical applications, with promise for the safe use in the treatment of cachexia, BPH, hypogonadism, breast cancer, and prostate cancer. Solomon ZJ, Mirabal JR, Mazur DJ, et al. Selective Androgen Receptor Modulators: Current Knowledge and Clinical Applications. Sex Med Rev 2019;7:84-94.

Direct conversion of human fibroblasts into functional Leydig-like cells by SF-1, GATA4 and NGFI-B

The reprogramming of fibroblasts to induced pluripotent stem cells raises the possibility that a somatic cell can be reprogrammed to an alternative, differentiated fate without first becoming a stem/progenitor cell. Recent work has shown that fibroblasts can be reprogrammed to other, terminally differentiated cells with a combination of several transcription factors. Here, we report that a combination of four developmental transcription factors; GATA4, SF-1, NGFI-B, and COUP TF2; efficiently reprogrammed human foreskin fibroblasts into functional induced Leydig-like cells (iLCs). The iLCs expressed Leydig-specific markers and secreted testosterone in vitro. We found that GATA4 and SF-1 were particularly critical for Leydig-specific markers expression and that GATA4, SF-1, and NGFI-B were necessary to generate functional iLCs that secreted testosterone. These findings demonstrate that fibroblasts can be directly converted into iLCs with a few, defined factors and may provide insight into potential therapies to treat testosterone deficiency.

Estrogens and Body Weight Regulation in Men

Our understanding of the metabolic roles of sex steroids in men has evolved substantially over recent decades. Whereas testosterone once was believed to contribute to metabolic risk in men, the importance of adequate androgen exposure for the maintenance of metabolic health has been demonstrated unequivocally. A growing body of evidence now also supports a critical role for estrogens in metabolic regulation in men. Recent data from clinical intervention studies indicate that estradiol may be a stronger determinant of adiposity than testosterone in men, and even short-term estradiol deprivation contributes to fat mass accrual. The following chapter will outline findings to date regarding the mechanisms, whereby estrogens contribute to the regulation of body weight and adiposity in men. It will present emergent clinical data as well as preclinical findings that reveal mechanistic insights into estrogen-mediated regulation of body composition. Findings in both males and females will be reviewed, to draw comparisons and to highlight knowledge gaps regarding estrogen action specifically in males. Finally, the clinical relevance of estrogen exposure in men will be discussed, particularly in the context of a rising global prevalence of obesity and expanding clinical use of sex steroid-based therapies in men.