Association of testosterone therapy with mortality, myocardial infarction, and stroke in men with low testosterone levels

Major cardiovascular disease risk in men with testosterone deficiency (hypogonadism): appraisal of short, medium and long-term testosterone therapy - a narrative review

INTRODUCTION

Low testosterone (T) levels are associated with obesity, metabolic syndrome, type 2 diabetes mellitus and altered lipid profiles, thus contributing to increased cardiovascular disease risk. Hence T deficiency has a detrimental effect on men's vascular health, quality of life and increased mortality.

OBJECTIVES

This review aims to present summary of data in the contemporary clinical literature pertaining to the benefits of T therapy in clinical studies with varying durations on vascular health in men with T deficiency.

METHODS

A Medline search using PubMed and EMBASE was performed using the following key words: "testosterone deficiency," "testosterone therapy," major cardiovascular adverse events", "cardiovascular disease". Relevant studies were extracted, evaluated, and analyzed. We evaluated findings from clinical trials, observational studies and systematic reviews and meta-analyses to develop a comprehensive account of the critical role of T in maintaining vascular health.

RESULTS

Considerable evidence beginning with studies published in 1940s concomitant with findings from the utmost recent clinical studies suggests a clinical value of T therapy in maintaining vascular health and reducing cardiovascular mortality. The current scientific and clinical evidence demonstrates strong relationship between low circulating T levels and risk of cardiovascular disease and T therapy is deemed safe in men with hypogonadism when given in the physiological range with no apparent harm.

CONCLUSION

What emerges from the current clinical literature is that, irrespective of the length of study durations, testosterone therapy provides significant health benefits and reduces risk of cardiovascular disease. More important is that data from many observational and registry studies, demonstrated that longer durations of testosterone therapy were associated with greater health benefits and reduced cardiovascular risk. T therapy in men with T deficiency reduces the incidence of major adverse cardiovascular events attributed to improving overall metabolic function.

Cardiovascular Impact of Androgen Deprivation Therapy: from Basic Biology to Clinical Practice

PURPOSE OF THE REVIEW

There have been increasing reports of cardiovascular complications of androgen deprivation therapy (ADT) leading to worse outcomes among patients with prostate cancer. While this may result from the direct effects of androgen suppression in the cardiovascular systems, there are ADT-type-specific distinct cardiovascular complications suggestive of mechanisms beyond androgen-mediated. Thus, it is critical to understand the biological and clinical impact of ADT on the cardiovascular system.

RECENT FINDINGS

Gonadotropin-releasing hormone (GnRH) agonists cause increased cardiovascular events compared to GnRH antagonists. Androgen receptor antagonists are linked to an increased risk of long QT syndrome, torsades de pointes, and sudden cardiac death. Androgen synthesis inhibitors are associated with increased rates of hypertension, atrial tachyarrhythmia, and, in rare incidences, heart failure. ADT increases the risk of cardiovascular disease. The risk among ADT drugs differs and must be evaluated to develop a medically optimal plan for prostate cancer patients.

Longitudinal Patterns in Testosterone Prescribing After US FDA Safety Communication in 2014

BACKGROUND

The objective of this study was to describe changes in testosterone prescribing following a 2014 US Food and Drug Administration (FDA) safety communication and how changes varied by physician characteristics.

METHODS

Data were extracted from a 20% random sample of Medicare fee-for-service administrative claims data from 2011 through 2019. The sample included 1,544,604 unique male beneficiaries who received evaluation and management (E&M) services from 58,819 unique physicians that prescribed testosterone between 2011 and 2013. Patients were categorized based on presence of coronary artery disease (CAD) and non-age-related hypogonadism. Physician characteristics were identified in the OneKey database and included specialty and affiliations with teaching hospitals, for-profit hospitals, hospitals in integrated delivery networks, and hospitals in the top decile of case mix index. Linear segmented models described how testosterone prescriptions changed following a 2014 FDA safety communication and how changes were associated with physician and organizational characteristics.

RESULTS

Among 65,089,560 physician-patient-quarter-year observations, mean (standard deviation) age ranged from 72.16 (5.84) years for observations without CAD or non-age-related hypogonadism to 75.73 (6.92) years with CAD and without non-age-related hypogonadism. Following the safety communication, immediate changes in off-label testosterone prescription levels fell by 0.22 percentage points (pp) (95% confidence interval [CI] -0.33 to -0.11) for patients with CAD and by -0.16 pp (95% CI -0.19 to -0.16) for patients without CAD. A similar change was noticed in on-label prescribing levels. Off-label testosterone prescription quarterly trend, however, increased for patients with CAD and without CAD; on-label testosterone prescription trends declined for both groups. Declines in off-label prescribing were larger when treated by primary care physicians vs. non-primary care physicians, and physicians affiliated with teaching compared to nonteaching hospitals. Physician and organizational characteristics were not associated with changes in on-label prescribing.

CONCLUSION

On-label and off-label testosterone therapy declined following the FDA safety communication. Certain physician characteristics were associated with changes in off-label, but not on-label, prescribing.

New Horizons: Testosterone or Exercise for Cardiometabolic Health in Older Men

Middle-aged and older men have typically accumulated comorbidities, are increasingly sedentary, and have lower testosterone concentrations (T) compared to younger men. Reduced physical activity (PA) and lower T both are associated with, and may predispose to, metabolically adverse changes in body composition, which contribute to higher risks of cardiometabolic disease. Exercise improves cardiometabolic health, but sustained participation is problematic. By contrast, rates of T prescription have increased, particularly in middle-aged and older men without organic diseases of the hypothalamus, pituitary, or testes, reflecting the unproven concept of a restorative hormone that preserves health. Two recent large randomized trials of T, and meta-analyses of randomized trials, did not show a signal for adverse cardiovascular (CV) events, and T treatment on a background of lifestyle intervention reduced type 2 diabetes by 40% in men at high risk. Men with both higher endogenous T and higher PA levels have lower CV risk, but causality remains unproven. Exercise training interventions improve blood pressure and endothelial function in middle-aged and older men, without comparable benefits or additive effects of T treatment. Therefore, exercise training improves cardiometabolic health in middle-aged and older men when effectively applied as a supervised regimen incorporating aerobic and resistance modalities. Treatment with T may have indirect cardiometabolic benefits, mediated via favorable changes in body composition. Further evaluation of T as a pharmacological intervention to improve cardiometabolic health in aging men could consider longer treatment durations and combination with targeted exercise programs.

Approach to the Patient: The Evaluation and Management of Men ≥50 Years With Low Serum Testosterone Concentration

Although testosterone replacement in men with classic hypogonadism due to an identified pathology of the hypothalamic-pituitary-testicular axis is uncontroversial, the role of testosterone treatment for men with age-related declines in circulating testosterone is unclear. This is due to the lack of large, long-term testosterone therapy trials assessing definitive clinical endpoints. However, men ≥50 years of age, particularly those who have a body mass index >25 kg/m2 and multiple comorbidities, commonly present with clinical features of androgen deficiency and low serum testosterone concentrations. Clinicians are faced with the question whether to initiate testosterone therapy, a difficult dilemma that entails a benefit-risk analysis with limited evidence from clinical trials. Using a case scenario, we present a practical approach to the clinical assessment and management of such men.

Sex Differences in Therapies against Myocardial Ischemia-Reperfusion Injury: From Basic Science to Clinical Perspectives

Mortality from myocardial infarction (MI) has declined over recent decades, which could be attributed in large part to improved treatment methods. Early reperfusion is the cornerstone of current MI treatment. However, reoxygenation via restored blood flow induces further damage to the myocardium, leading to ischemia-reperfusion injury (IRI). While experimental studies overwhelmingly demonstrate that females experience greater functional recovery from MI and decreased severity in the underlying pathophysiological mechanisms, the outcomes of MI with subsequent reperfusion therapy, which is the clinical correlate of myocardial IRI, are generally poorer for women compared with men. Distressingly, women are also reported to benefit less from current guideline-based therapies compared with men. These seemingly contradicting outcomes between experimental and clinical studies show a need for further investigation of sex-based differences in disease pathophysiology, treatment response, and a sex-specific approach in the development of novel therapeutic methods against myocardial IRI. In this literature review, we summarize the current knowledge on sex differences in the underlying pathophysiological mechanisms of myocardial IRI, including the roles of sex hormones and sex chromosomes. Furthermore, we address sex differences in pharmacokinetics, pharmacodynamics, and pharmacogenetics of current drugs prescribed to limit myocardial IRI. Lastly, we highlight ongoing clinical trials assessing novel pharmacological treatments against myocardial IRI and sex differences that may underlie the efficacy of these new therapeutic approaches.

A Review on the Impact of Oxidative Stress and Medicinal Plants on Leydig Cells

Leydig cells are essential for steroidogenesis and spermatogenesis. An imbalance in the production of reactive oxygen species (ROS) and the cellular antioxidant level brings about oxidative stress. Oxidative stress (OS) results in the dysfunction of Leydig cells, thereby impairing steroidogenesis, spermatogenesis, and ultimately, male infertility. To prevent Leydig cells from oxidative insults, there needs to be a balance between the ROS production and the cellular protective capacity of antioxidants. Evidence indicates that medicinal plants could improve Leydig cell function at specific concentrations under basal or OS conditions. The increased usage of medicinal plants has been considered a possible alternative treatment for male infertility. This review aims to provide an overview of the impact of oxidative stress on Leydig cells as well as the effects of various medicinal plant extracts on TM3 Leydig cells. The medicinal plants of interest include Aspalathus linearis, Camellia sinensis, Moringa oleifera, Morinda officinale, Taraxacum officinale, Trichilia emetica, Terminalia sambesiaca, Peltophorum africanum, Ximenia caffra, Serenoa repens, Zingiber officinale, Eugenia jambolana, and a combination of dandelion and fermented rooibos (CRS-10). According to the findings obtained from studies conducted on the evaluated medicinal plants, it can, therefore, be concluded that the medicinal plants maintain the antioxidant profile of Leydig cells under basal conditions and have protective or restorative effects following exposure to oxidative stress. The available data suggest that the protective role exhibited by the evaluated plants may be attributed to their antioxidant content. Additionally, the use of the optimal dosage or concentration of the extracts in the management of oxidative stress is of the utmost importance, and the measurement of their oxidation reduction potential is recommended.

Recent advances in endocrine organoids for therapeutic application

The endocrine system, consisting of the hypothalamus, pituitary, endocrine glands, and hormones, plays a critical role in hormone metabolic interactions. The complexity of the endocrine system is a significant obstacle to understanding and treating endocrine disorders. Notably, advances in endocrine organoid generation allow a deeper understanding of the endocrine system by providing better comprehension of molecular mechanisms of pathogenesis. Here, we highlight recent advances in endocrine organoids for a wide range of therapeutic applications, from cell transplantation therapy to drug toxicity screening, combined with development in stem cell differentiation and gene editing technologies. In particular, we provide insights into the transplantation of endocrine organoids to reverse endocrine dysfunctions and progress in developing strategies for better engraftments. We also discuss the gap between preclinical and clinical research. Finally, we provide future perspectives for research on endocrine organoids for the development of more effective treatments for endocrine disorders.

Higher testosterone and testosterone/estradiol ratio in men are associated with better epigenetic estimators of mortality risk

Introduction

Sex hormones are hypothesized to drive sex-specific health disparities. Here, we study the association between sex steroid hormones and DNA methylation-based (DNAm) biomarkers of age and mortality risk including Pheno Age Acceleration (AA), Grim AA, and DNAm-based estimators of Plasminogen Activator Inhibitor 1 (PAI1), and leptin concentrations.

Methods

We pooled data from three population-based cohorts, the Framingham Heart Study Offspring Cohort (FHS), the Baltimore Longitudinal Study of Aging (BLSA), and the InCHIANTI Study, including 1,062 postmenopausal women without hormone therapy and 1,612 men of European descent. Sex hormone concentrations were standardized with mean 0 and standard deviation of 1, for each study and sex separately. Sex-stratified analyses using a linear mixed regression were performed, with a Benjamini-Hochberg (BH) adjustment for multiple testing. Sensitivity analysis was performed excluding the previously used training-set for the development of Pheno and Grim age.

Results

Sex Hormone Binding Globulin (SHBG) is associated with a decrease in DNAm PAI1 among men (per 1 standard deviation (SD): -478 pg/mL; 95%CI: -614 to -343; P:1e-11; BH-P: 1e-10), and women (-434 pg/mL; 95%CI: -589 to -279; P:1e-7; BH-P:2e-6). The testosterone/estradiol (TE) ratio was associated with a decrease in Pheno AA (-0.41 years; 95%CI: -0.70 to -0.12; P:0.01; BH-P: 0.04), and DNAm PAI1 (-351 pg/mL; 95%CI: -486 to -217; P:4e-7; BH-P:3e-6) among men. In men, 1 SD increase in total testosterone was associated with a decrease in DNAm PAI1 (-481 pg/mL; 95%CI: -613 to -349; P:2e-12; BH-P:6e-11).

Conclusion

SHBG was associated with lower DNAm PAI1 among men and women. Higher testosterone and testosterone/estradiol ratio were associated with lower DNAm PAI and a younger epigenetic age in men. A decrease in DNAm PAI1 is associated with lower mortality and morbidity risk indicating a potential protective effect of testosterone on lifespan and conceivably cardiovascular health via DNAm PAI1.

Anabolic androgenic steroids and cardiomyopathy: an update

Anabolic androgenic steroids (AAS) include endogenously produced androgens like testosterone and their synthetic derivatives. Their influence on multiple metabolic pathways across organ systems results in an extensive side effect profile. From creating an atherogenic and prothrombotic milieu to direct myocardial injury, the effects of AAS on the heart may culminate with patients requiring thorough cardiac evaluation and multi-disciplinary medical management related to cardiomyopathy and heart failure (HF). Supraphysiological doses of AAS have been shown to induce cardiomyopathy via biventricular dysfunction. Advancement in imaging including cardiac magnetic resonance imaging (MRI) and additional diagnostic testing have facilitated the identification of AAS-induced left ventricular dysfunction, but data regarding the impact on right ventricular function remains limited. Emerging studies showed conflicting data regarding the reversibility of AAS-induced cardiomyopathy. There is an unmet need for a systematic long-term outcomes study to empirically evaluate the clinical course of cardiomyopathy and to assess potential targeted therapy as appropriate. In this review, we provide an overview of the epidemiology, pathophysiology and management considerations related to AAS and cardiomyopathy.

Cardiovascular Safety of Testosterone-Replacement Therapy

BACKGROUND

The cardiovascular safety of testosterone-replacement therapy in middle-aged and older men with hypogonadism has not been determined.

METHODS

In a multicenter, randomized, double-blind, placebo-controlled, noninferiority trial, we enrolled 5246 men 45 to 80 years of age who had preexisting or a high risk of cardiovascular disease and who reported symptoms of hypogonadism and had two fasting testosterone levels of less than 300 ng per deciliter. Patients were randomly assigned to receive daily transdermal 1.62% testosterone gel (dose adjusted to maintain testosterone levels between 350 and 750 ng per deciliter) or placebo gel. The primary cardiovascular safety end point was the first occurrence of any component of a composite of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke, assessed in a time-to-event analysis. A secondary cardiovascular end point was the first occurrence of any component of the composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization, assessed in a time-to-event analysis. Noninferiority required an upper limit of less than 1.5 for the 95% confidence interval of the hazard ratio among patients receiving at least one dose of testosterone or placebo.

RESULTS

The mean (±SD) duration of treatment was 21.7±14.1 months, and the mean follow-up was 33.0±12.1 months. A primary cardiovascular end-point event occurred in 182 patients (7.0%) in the testosterone group and in 190 patients (7.3%) in the placebo group (hazard ratio, 0.96; 95% confidence interval, 0.78 to 1.17; P<0.001 for noninferiority). Similar findings were observed in sensitivity analyses in which data on events were censored at various times after discontinuation of testosterone or placebo. The incidence of secondary end-point events or of each of the events of the composite primary cardiovascular end point appeared to be similar in the two groups. A higher incidence of atrial fibrillation, of acute kidney injury, and of pulmonary embolism was observed in the testosterone group.

CONCLUSIONS

In men with hypogonadism and preexisting or a high risk of cardiovascular disease, testosterone-replacement therapy was noninferior to placebo with respect to the incidence of major adverse cardiac events. (Funded by AbbVie and others; TRAVERSE ClinicalTrials.gov number, NCT03518034.).

Major adverse cardiovascular events associated with testosterone treatment: a pharmacovigilance study of the FAERS database

Background and purpose: Testosterone is an essential sex hormone in maintaining masculine characteristics, which is prescribed for male hypogonadism as testosterone replacement treatment (TRT). Herein, we investigated long-standing controversies about the association between TRT and major adverse cardiovascular events (MACEs), based on real world adverse event (AE) reports, registered in the Food and Drug Administration Adverse Event Reporting System (FAERS). Methods: Publicly available FAERS data from 1 January 2004 to 31 December 2022 were retrieved from the Food and Drug Administration (FDA) website. The data mining protocol including the reporting odds ratio (ROR) and the Bayesian confidence propagation neural network (BCPNN) was applied to analyze overreporting caused by risk factors and MACEs, including TRT, morbidities, and ages. The ROR and the BCPNN were also applied to investigate the annually developing trend of pharmacovigilance (PV) signals in the real world, retrospectively. Results: A total of 3,057 cases referring to MACEs, with a median age of 57 years old (yo), were identified from 28,921 cases of testosterone users. MACEs related to PV signals have emerged since 2014, including cardiac death, non-fatal myocardial infarction, and non-fatal stroke. Myocardial infarction (MI) (ROR: 9.46; IC₀₂₅: 3.08), acute myocardial infarction (AMI) (ROR: 16.20; IC₀₂₅: 3.72), ischemic cardiomyopathy (ROR: 11.63; IC₀₂₅: 2.20), and cardiomyopathy (ROR: 5.98; IC₀₂₅: 1.96) were the most significant signals generated, and weaker signals included cardiac failure acute (ROR: 4.01; IC₀₂₅: 0.71), cardiac arrest (ROR: 1.88; IC₀₂₅: 0.56), and ventricular fibrillation (VF) (ROR: 2.38; IC₀₂₅: 0.38). The time-to-onset (TTO) of MACEs was calculated with a median of 246 days for AMI. Conclusion: For myocardial infarction and cardiomyopathy, TRT statistically tended to increase the risk of MACEs, while for cardiac arrhythmia, cardiac failure, and stroke, TRT demonstrated beneficial effects among the population with morbidities, such as testosterone deficiency (TD), diabetes mellitus (DM), and hypertension. MACEs were rare but led to serious outcomes including significant increase in death and disability. Since 2018, and before 2014, reports referring to TRT associated with MACEs were relatively scarce, which indicated that there might be a considerable number of cases that went unrecorded, due to neglection. Health workers and testosterone users might pay more attention to testosterone-induced MACEs.

The British Society for Sexual Medicine Guidelines on Male Adult Testosterone Deficiency, with Statements for Practice

Testosterone deficiency (TD) is an increasingly common problem with significant health implications, but its diagnosis and management can be challenging. A multi-disciplinary panel from BSSM reviewed the available literature on TD and provide evidence-based statements for clinical practice. Evidence was derived from Medline, EMBASE and Cochrane searches on hypogonadism, testosterone therapy (T Therapy) and cardiovascular safety from May 2017 to September 2022. This revealed 1,714 articles, including 52 clinical trials and 32 placebo-controlled randomised controlled trials. A total of twenty-five statements are provided, relating to five key areas: screening, diagnosis, initiating T Therapy, benefits and risks of T Therapy, and follow-up. Seven statements are supported by level 1 evidence, eight by level 2, five by level 3, and five by level 4. Recent studies have demonstrated that low levels of testosterone in men are associated with increased risk of incident type 2 diabetes mellitus, worse outcomes in chronic kidney disease and COVID 19 infection with increased all-cause mortality, along with significant quality of life implications. These guidelines should help practitioners to effectively diagnose and manage primary and age-related TD.

Development and Validation of Quality Measures for Testosterone Prescribing

Context

Accurate measures to assess appropriateness of testosterone prescribing are needed to improve prescribing practices.

Objective

This work aimed to develop and validate quality measures around the initiation and monitoring of testosterone prescribing.

Methods

This retrospective cohort study comprised a national cohort of male patients receiving care in the Veterans Health Administration who initiated testosterone during January or February 2020. Using laboratory data and diagnostic codes, we developed 9 initiation and 7 monitoring measures. These were based on the current Endocrine Society guidelines supplemented by expert opinion and prior work. We chose measures that could be operationalized using national VA electronic health record (EHR) data. We assessed criterion validity for these 16 measures by manual review of 142 charts. Main outcome measures included positive and negative predictive values (PPVs, NPVs), overall accuracy (OA), and Matthews Correlation Coefficients (MCCs).

Results

We found high PPVs (>78%), NPVs (>98%), OA (≥94%), and MCCs (>0.85) for the 10 measures based on laboratory data (5 initiation and 5 monitoring). For the 6 measures relying on diagnostic codes, we similarly found high NPVs (100%) and OAs (≥98%). However, PPVs for measures of acute conditions occurring before testosterone initiation (ie, acute myocardial infarction or stroke) or new conditions occurring after initiation (ie, prostate or breast cancer) PPVs were much lower (0% to 50%) due to few or no cases.

Conclusion

We developed several valid EHR-based quality measures for assessing testosterone-prescribing practices. Deployment of these measures in health care systems can facilitate identification of quality gaps in testosterone-prescribing and improve care of men with hypogonadism.

The Relationship Between Testosterone Therapy and Rotator Cuff Tears, Repairs, and Revision Repairs

INTRODUCTION

The purpose of this study was to evaluate rates of rotator cuff tears (RCTs), repairs (RCRs), and revision RCR in patients who were prescribed testosterone replacement therapy (TRT) and compare these patients with a control group.

METHODS

The PearlDiver database was queried for patients who were prescribed testosterone for at least 90 days between 2011 and 2018 to evaluate the incidence of RCTs in this population. A second analysis evaluated patients who sustained RCTs using International Classification of Diseases, 9th/10th codes to evaluate these patients for rates of RCR and revision RCR. Chi square analysis and multivariate regression analyses were used to compare rates of RCTs, RCR, and subsequent or revision RCR between the testosterone and control groups, with a P -value of 0.05 representing statistical significance.

RESULTS

A total of 673,862 patients with RCT were included for analysis, and 9,168 of these patients were prescribed testosterone for at least 90 days before their RCT. The TRT group had a 3.6 times greater risk of sustaining an RCT (1.14% versus 0.19%; adjusted odds ratio (OR) 3.57; 95% confidence interval (CI) 3.57 to 3.96). A 1.6 times greater rate of RCR was observed in the TRT cohort (TRT, 46.4% RCR rate and control, 34.0% RCR rate; adjusted OR 1.60; 95% CI 1.54 to 1.67). The TRT cohort had a 26.7 times greater risk of undergoing a subsequent RCR, irrespective of laterality, within 1 year of undergoing a primary RCR when compared with the control group (TRT, 47.1% and control, 4.0%; adjusted OR 26.4; 95% CI 25.0 to 27.9, P < 0.001).

CONCLUSIONS

There is increased risk of RCTs, RCRs, and subsequent RCRs in patients prescribed testosterone. This finding may represent a musculoskeletal consequence of TRT and is important for patients and clinicians to understand. Additional research into the science of tendon injury in the setting of exogenous anabolic steroids remains of interest.

LEVEL OF EVIDENCE

Level Ⅲ, retrospective cohort study.

Male Reproduction and Aging

Recent publications of well-conducted population studies have informed us that the syndromic prevalence of age-related low testosterone, also known as late-onset hypogonadism, is quite low. Several well-conducted trials in middle-aged and older men with age-related decline in testosterone levels have revealed that efficacy of testosterone therapy is modest with improvement in sexual function, mood, volumetric bone density, and anemia. Although select older men might benefit from testosterone therapy, its effect on prostate cancer risk and major adverse cardiovascular events remains unclear. The results of the ongoing TRAVERSE trial will likely provide important insights into these risks.

Testosterone Usage Leading to Pulmonary Embolisms and Deep Vein Thrombosis: A Case Report and Review of the Literature

Androgen usage has widely increased in recent times via prescribed and unprescribed means. Testosterone is a popular androgen taken by both athletes and the general population. While there is some evidence of androgens being thrombogenic, we report on a 19-year-old male who presented to the hospital after the usage of testosterone for one month, leading to the development of multiple pulmonary emboli and deep vein thrombosis. The authors hope to elucidate the relationship between testosterone usage and thrombosis formation.

Androgen receptor blockade by flutamide down-regulates renal fibrosis, inflammation, and apoptosis pathways in male rats

AIM

this study aims to explore the effect of androgen receptor (AR) blockade by flutamide on some renal pathologic changes such as inflammation, apoptosis, and fibrosis in male rats.

MAIN METHODS

Firstly, we investigated the potential effect of AR blockade on renal inflammatory intermediates including IL-1β, IL-6, TNF-α, NF-Қβ proteins, and the renal gene expression of NF-Қβ. Besides inflammation, we also assessed the apoptosis pathways including the caspases 3 & 9, mTOR, pAKT proteins, and BAX gene expression. Besides inflammation and apoptosis pathways, we also investigated the effect of androgen blockade on renal fibrosis intermediates including vimentin, TGFβ-1, α-SMA, MMP-9, collagen type-III, collagen type-IV, and the renal expression of the col1A1 gene. Besides previous pathological pathways, we assessed the expression of chloride channel protein-5 (ClC-5), as an important regulator of many renal pathological changes. Finally, we assessed the impact of previous pathological changes on renal function at biochemical and pathological levels.

KEY FINDINGS

We found that AR blockade by flutamide was associated with the down-regulation of renal inflammation, apoptosis, and fibrosis markers. It was associated with expression down-regulation of IL-1β & IL-6, TNF-α, NF-Қβ, caspases 3 & 9, mTOR, MMP-9, collagens, TGFβ-1, and α-SMA. Away from down-regulation, we also found that AR blockade has upregulated ClC-5 and pAKT proteins.

SIGNIFICANCE

AR is a major player in androgens-induced nephrotoxicity. AR blockade downregulates renal fibrosis, inflammation, and apoptosis pathways. It may be helpful as a strategy for alleviation of renal side effects associated with some drugs. However; this needs further investigations.

Risk Assessment and Coronary Artery Calcium Scoring in Transgender and Gender-Diverse Individuals Receiving Gender-Affirming Hormone Therapy

OBJECTIVE

To evaluate cardiovascular risk factors and prevalent coronary artery disease (CAD) using Coronary Artery Calcium (CAC) scoring in transgender and gender-diverse (TGD) individuals receiving gender-affirming hormone therapy (GAHT) and compare the CAC scores of TGD individuals with those of the general population.

METHODS

TGD individuals aged ≥30 years, without known risk factors for cardiovascular disease (CVD), other than tobacco use and family history of CVD, on GAHT were recruited, and baseline information, including metabolic parameters, was collected. CAC scores were obtained and compared with those of a cisgender age-matched population.

RESULTS

Of 25 transwomen recruited, 24 underwent CAC scans. Of them, 2 (8.3%) had a CAC score of >0 to 99 and 1 (4.1%) had a CAC score of ≥100. Of 22 transmen recruited, 16 underwent CAC scans. Of them, 26 (12.5%) had a CAC score of >0 to 99 and none had a CAC score of ≥100. Framingham Risk Scores were not correlated with the presence of CAC.

CONCLUSION

The presence of CAC in this small cohort of TGD individuals on GAHT was similar to that in the cisgender age-matched population. CAC scoring is a means to assess the prevalence of CAD in TGD individuals and identify those in whom aggressive risk reduction is indicated.

Epidemiology and prevention of venous thromboembolism

Venous thromboembolism, that consists of the interrelated conditions deep-vein thrombosis and pulmonary embolism, is an under-appreciated vascular disease. In Western regions, approximately 1 in 12 individuals will be diagnosed with venous thromboembolism in their lifetime. Rates of venous thromboembolism are lower in Asia, but data from other regions are sparse. Numerous risk factors for venous thromboembolism have been identified, which can be classified as acute or subacute triggers (provoking factors that increase the risk of venous thromboembolism) and basal or acquired risk factors (which can be modifiable or static). Approximately 20% of individuals who have a venous thromboembolism event die within 1 year (although often from the provoking condition), and complications are common among survivors. Fortunately, opportunities exist for primordial prevention (prevention of the development of underlying risk factors), primary prevention (management of risk factors among individuals at high risk of the condition) and secondary prevention (prevention of recurrent events) of venous thromboembolism. In this Review, we describe the epidemiology of venous thromboembolism, including the incidence, risk factors, outcomes and opportunities for prevention. Meaningful health disparities exist in both the incidence and outcomes of venous thromboembolism. We also discuss these disparities as well as opportunities to reduce them.

Involvement of p38 MAPK in Leydig cell aging and age-related decline in testosterone

Introduction

Age-related decline in testosterone is associated with Leydig cell aging with impaired testosterone synthesis in aging. Obesity accelerates the age-related decline in testosterone. However, the mechanisms underlying the Leydig cell aging and the effects of obesity on Leydig cell aging remain unclear.

Method

Natural aging mice and diet-induced obese mice were used to assess the process of testicular Leydig cell senescence with age or obesity. Bioinformatic analysis of the young and aged human testes was used to explore key genes related Leydig cell aging. Leydig cell-specific p38 MAPK knockout (p38LCKO) mice were used to further analyze the roles of p38 MAPK in Leydig cell aging. The levels of testosterone and steroidogenic enzymes, activity of p38 MAPK, aging status of Leydig cells, and oxidative stress and inflammation of testes or Leydig cells were detected by ELISA, immunoblotting, immunofluorescence, and senescence-associated β-galactosidase (SA-β-Gal) staining analysis, respectively.

Result

The serum testosterone level was significantly reduced in aged mice compared with young mice. In the testis of aged mice, the reduced mRNA and protein levels of LHCGR, SRB1, StAR, CYP11A1, and CYP17A1 and the elevated oxidative stress and inflammation were observed. KEGG analysis showed that MAPK pathway was changed in aged Leydig cells, and immunoblotting displayed that p38 MAPK was activated in aged Leydig cells. The intensity of SA-β-Gal staining on Leydig cells and the number of p21-postive Leydig cells in aged mice were more than those of young mice. Similar to aged mice, the testosterone-related indexes decreased, and the age-related indexes increased in the testicular Leydig cells of high fat diet (HFD) mice. Aged p38LCKO mice had higher levels of testosterone and steroidogenic enzymes than those of age-matched wild-type (WT) littermates, with reduced the intensity of SA-β-Gal staining and the expression of p21 protein.

Conclusion

Our study suggested that obesity was an important risk factor for Leydig cell aging. p38 MAPK was involved in Leydig cell aging induced by age and obesity. The inhibition of p38 MAPK could delay Leydig cell aging and alleviate decline in testosterone.

The future of evolutionary medicine: sparking innovation in biomedicine and public health

Evolutionary medicine - i.e. the application of insights from evolution and ecology to biomedicine - has tremendous untapped potential to spark transformational innovation in biomedical research, clinical care and public health. Fundamentally, a systematic mapping across the full diversity of life is required to identify animal model systems for disease vulnerability, resistance, and counter-resistance that could lead to novel clinical treatments. Evolutionary dynamics should guide novel therapeutic approaches that target the development of treatment resistance in cancers (e.g., via adaptive or extinction therapy) and antimicrobial resistance (e.g., via innovations in chemistry, antimicrobial usage, and phage therapy). With respect to public health, the insight that many modern human pathologies (e.g., obesity) result from mismatches between the ecologies in which we evolved and our modern environments has important implications for disease prevention. Life-history evolution can also shed important light on patterns of disease burden, for example in reproductive health. Experience during the COVID-19 (SARS-CoV-2) pandemic has underlined the critical role of evolutionary dynamics (e.g., with respect to virulence and transmissibility) in predicting and managing this and future pandemics, and in using evolutionary principles to understand and address aspects of human behavior that impede biomedical innovation and public health (e.g., unhealthy behaviors and vaccine hesitancy). In conclusion, greater interdisciplinary collaboration is vital to systematically leverage the insight-generating power of evolutionary medicine to better understand, prevent, and treat existing and emerging threats to human, animal, and planetary health.

Cardiovascular and metabolic actions of the androgens: Is testosterone a Janus-faced molecule?

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide and in the Western world, one-third of all deaths are attributed to CVD. A conspicuous characteristic of this healthcare epidemic is that most CVD is higher in men than in age-matched premenopausal women, yet reasons for these obvious sex differences remain poorly understood. Driven by clinical case and epidemiological studies and supported by animal experiments, a strong dogma emerged early on that testosterone (TES) exerts deleterious effects on cardiovascular health and exacerbates development of CVD and metabolic dysfunctions in men. In this review, earlier and more recent clinical and experimental animal evidence of cardiovascular and metabolic effects of androgens are discussed. The more recent evidence overwhelmingly suggests that it is progressive, age-dependent declines in TES levels in men that exacerbate CVD and metabolic dysfunctions, while TES exerts beneficial systemic hypotensive effects and protects against metabolic syndrome (MetS) and type2 diabetes mellitus (T2DM). Recent findings reveal existence of bi-directional modulation of glucose and fat homeostasis by TES in females vs males, such that age-dependent declines in TES levels in males and abnormal increases in normally low TES levels in females both result in similar dysfunction in glucose and fat homeostasis, resulting in development of MetS and T2DM, central risk factors for development of CVD, in men as well as women. These findings suggest that the long-held view that TES is detrimental to male health should be discarded in favor of the view that, at least in men, TES is beneficial to cardiovascular and metabolic health.

Evaluating and implementing block jackknife resampling Mendelian randomization to mitigate bias induced by overlapping samples

Participant overlap can induce overfitting bias into Mendelian randomization (MR) and polygenic risk score (PRS) studies. Here, we evaluated a block jackknife resampling framework for genome-wide association studies (GWAS) and PRS construction to mitigate overfitting bias in MR analyses and implemented this study design in a causal inference setting using data from the UK Biobank. We simulated PRS and MR under three scenarios: (1) using weighted SNP estimates from an external GWAS, (2) using weighted SNP estimates from an overlapping GWAS sample and (3) using a block jackknife resampling framework. Based on a P-value threshold to derive genetic instruments for MR studies (P < 5 × 10-8) and a 10% variance in the exposure explained by all SNPs, block-jackknifing PRS did not suffer from overfitting bias (mean R2 = 0.034) compared with the externally weighted PRS (mean R2 = 0.040). In contrast, genetic instruments derived from overlapping samples explained a higher variance (mean R2 = 0.048) compared with the externally derived score. Overfitting became considerably more severe when using a more liberal P-value threshold to construct PRS (e.g. P < 0.05, overlapping sample PRS mean R2 = 0.103, externally weighted PRS mean R2 = 0.086), whereas estimates using jackknife score remained robust to overfitting (mean R2 = 0.084). Using block jackknife resampling MR in an applied analysis, we examined the effects of body mass index on circulating biomarkers which provided comparable estimates to an externally weighted instrument, whereas the overfitted scores typically provided narrower confidence intervals. Furthermore, we extended this framework into sex-stratified, multivariate and bidirectional settings to investigate the effect of childhood body size on adult testosterone levels.

Oral administration of VDAC1-derived small molecule peptides increases circulating testosterone levels in male rats

Cholesterol is the precursor of all steroid hormones, and the entry of cholesterol into the mitochondria is the rate-limiting step of steroidogenesis. Voltage-dependent anion channel (VDAC1) is an outer mitochondrial protein part of a multiprotein complex that imports cholesterol. We previously reported that intratesticular administration of a 25 amino acid peptide blocking the interaction between 14-3-3ϵ with VDAC1 increased circulating levels of testosterone. This fusion peptide was composed of a HIV-1 transactivator of transcription (TAT) protein transduction domain cell-penetrating peptide, a glycine linker, and amino acids 159-172 of VDAC1 (TV159-172). Here, we describe the development of a family of small molecules that increase circulating testosterone levels after an oral administration. We first characterized an animal model where TV159-172 was delivered subcutaneously. This subcutaneous model allowed us to study the interactions between TV159-172 and the hypothalamus-pituitary-gonadal axis (HPG) and identify the biologically active core of TV159-172. The core consisted of the tetrapeptide RVTQ, which we used as a platform to design synthetic peptide derivatives that can be administered orally. We developed a second animal model to test various derivatives of RVTQ and found 11 active compounds. Dose-response experiments identified 4 synthetic peptides that robustly increased androgen levels in a specific manner. We selected RdVTQ as the leading VDAC1-core derivative and profiled the response across the lifespan of Brown-Norway rats. In summary, we present the development of a new class of therapeutics that act within the HPG axis to increase testosterone levels specifically. This new class of small molecules self-regulates, preventing abuse.

Testosterone therapy and cancer risks among men in the SEER-Medicare linked database

BACKGROUND

We examined associations between two forms of testosterone therapy (TT) and risks of seven cancers among men.

METHODS

SEER-Medicare combines cancer registry data from the Surveillance, Epidemiology, and End Results programme with Medicare claims. Our population-based case-control study included incident cancer cases diagnosed between 1992-2015: prostate (n = 130,713), lung (n = 105,466), colorectal (n = 56,433), bladder (n = 38,873), non-Hodgkin lymphoma (n = 17,854), melanoma (n = 14,241), and oesophageal (n = 9116). We selected 100,000 controls from a 5% random sample of Medicare beneficiaries and used logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

TT was associated with lower risk of distant-stage prostate cancer (injection/implantation OR = 0.72, 95% CI: 0.60-0.86; topical OR = 0.50, 95% CI: 0.24-1.03). We also observed inverse associations for distant-stage colorectal cancer (injection/implantation OR = 0.75, 95% CI: 0.62-0.90; topical OR = 0.11, 95% CI: 0.05-0.24). Risks of distant-stage colorectal and prostate cancers decreased with time after initiating TT by injection/implantation. By contrast, TT was positively associated with distant-stage melanoma (injection/implantation OR = 1.70, 95% CI: 1.37-2.11). TT was not associated with bladder cancer, oesophageal cancer, lung cancer or non-Hodgkin lymphoma.

CONCLUSION

TT was inversely associated with distant-stage prostate and colorectal cancers but was positively associated with distant-stage melanoma. These observations may suggest an aetiologic role for TT or the presence of residual confounding.

Sex-specific and hormone-related differences in vascular remodelling in atherosclerosis

Atherosclerosis, a lipid-driven inflammatory disease, is the main underlying cause of cardiovascular diseases (CVDs) both in men and women. Sex-related dimorphisms regarding CVDs and atherosclerosis were observed since more than a decade ago. Inflammatory mediators such as cytokines, but also endothelial dysfunction, vascular smooth muscle cell migration and proliferation lead to vascular remodelling but are differentially affected by sex. Each year a greater number of men die of CVDs compared with women and are also affected by CVDs at an earlier age (40-70 years old) while women develop atherosclerosis-related complications mainly after menopause (60+ years). The exact biological reasons behind this discrepancy are still not well-understood. From the numerous animal studies on atherosclerosis, only a few include both sexes and even less investigate and highlight the sex-specific differences that may arise. Endogenous sex hormones such as testosterone and oestrogen modulate the atherosclerotic plaque composition and the frequency of such plaques. In men, testosterone seems to act like a double-edged sword as its decrease with ageing correlates with an increased risk of atherosclerotic CVDs, while testosterone is also reported to promote inflammatory immune cell recruitment into the atherosclerotic plaque. In premenopausal women, oestrogen exerts anti-atherosclerotic effects, which decline together with its level after menopause resulting in increased CVD risk in ageing women. However, the interplay of sex hormones, sex-specific immune responses and other sex-related factors is still incompletely understood. This review highlights reported sex differences in atherosclerotic vascular remodelling and the role of endogenous sex hormones in this process.

Recognizing the True Value of Testosterone Therapy in Health Care

There has been little recognition within the medical community of the health impact of testosterone (T) deficiency (TD), also known as hypogonadism, and the substantial benefits of testosterone therapy (TTh) on health and quality of life despite high-level clinical evidence. In a roundtable symposium, investigators summarized the contemporary evidence in several key clinical areas. TD negatively impacts human health and quality of life and is associated with increased mortality. Several studies have demonstrated that TTh in men with TD reduced all-cause and cardiovascular mortality. The longstanding belief that TTh is associated with increased prostate cancer (PCa) risk is contradicted by recent evidence, including multiple studies showing that TTh is associated with reduced PCa risk. Similarly, the weight of current evidence indicates the purported concern that TTh is associated with increased cardiovascular risk is incorrect. Normalization of physiological T reduces myocardial infarction, stroke, and deaths compared with men whose testosterone levels failed to normalize. In diabetic men TTh improves insulin resistance, and a large 2-year controlled study in men with abnormal glucose tolerance showed a substantially reduced rate of diabetes among men treated with TTh compared with untreated controls. Long-term TTh in diabetic men resulted in progressive improvements in obesity and insulin requirements, including a substantial number who experienced complete remission of diabetes. Finally, TTh has been shown to reduce severe outcomes with Covid-19 infection. These lines of evidence argue strongly for the need for greater awareness in the medical community of the impact of TD on health, and of the health benefits of TTh.

Testosterone treatment of late-onset hypogonadism - benefits and risks

As men age, their serum testosterone concentration falls, the total testosterone concentration barely but the free testosterone concentration more so. Testosterone treatment of older men who have low testosterone concentrations can ameliorate several consequences of this fall, including libido and sexual activity, distance walked, hemoglobin and volumetric bone mineral density and strength, but not vitality and cognitive function. The possibility that testosterone treatment of late-onset hypogonadism increases the risks of benign prostatic hyperplasia, prostate cancer or heart disease has been suggested but will not be determined until larger and longer trials are conducted.

The medicalization of testosterone: reinventing the elixir of life

The pursuit of longevity, which during the Renaissance era was limited to longing for miraculous ways of rejuvenation, such as bathing in the fountain of youth, took a scientific turn in 1889 with the publication of Brown-Sequard's self-experiments with an extract of animal testes, which apparently improved his vitality, physical strength and cognition. This extract, marketed then as the "Elixir of Life", was sold for decades throughout Europe and North America. However, recent replication of Brown-Sequard's experiments demonstrated that such an extract only contains homeopathic concentrations of testosterone that are insufficient to exert any biological effect. Thus, the birth of Andrology began with a placebo effect. Over the past few decades, the quest for compounds that might lead to rejuvenation has regained traction, with testosterone being at the forefront. Though clinical practice guidelines advocate testosterone therapy in men with organic hypogonadism-the only indication approved by the Food and Drug Administration-testosterone continues to be marketed as a wonder drug with rejuvenating effects on sexual function, vitality, and a host of other unproven benefits. Additionally, the epidemic of obesity and diabetes, conditions associated with low testosterone, has further brought testosterone into the limelight. Although the number of testosterone prescriptions written have increased several-fold in the past two decades, carefully conducted randomized trials suggest modest benefits of testosterone therapy. At the same time, safety concerns, particularly in older men, remain valid.

Role of Sex in Atherosclerosis: Does Sex Matter?

PURPOSE OF REVIEW

Atherosclerosis is the largest cause of death in the western world with the role of sex yet to be determined. The purpose of this review is to investigate the role sex may play in the development of atherosclerosis.

RECENT FINDINGS

Differences in plaque burden play a role in atherosclerotic outcome. Men have a higher prevalence of plaque burden, while women have less plaque rupture, necrotic core, and calcium. Differences in hormones, vascular anatomy, and overall lifestyle all play a role. Estrogen's cardioprotective effect is well known, but there is a lack of consensus on testosterone's role. There are varying rates of atherosclerosis between the sexes. Studies have also shown varying differences in the progression of plaque and the type of plaques between sexes. Further investigations need to be done to solidify the role sex may play as a variable in the development of atherosclerosis and how that may impact future treatment goals.

Correlates of testosterone change as men age

Objective: The literature on testosterone (T) in men reports diverse correlates of T, some with minimal empirical support and most with little indication of how they change with advancing age. We test eight putative correlations across age.Method: Correlations were tested on a large sample of British men.Results: Seven of eight correlations replicated. Most change across men's life courses. The diurnal cycle of T is considerably weaker among older than younger men. Single men have higher T than married men of the same age; however, this difference lessens as men get older. Elevated T among smokers is less pronounced as men age. The inverse relationship between obesity and T is sustained across the adult age range. The lessening of T with age is well established, however there is disagreement about the course of decline. We find T having a steep decline around age 30, with possibly a rebound around age 50, after which levels remain roughly constant. Correlations involving health become stronger among older men. After age 30 or 40, the inverse relationships between T and HbA1c, diabetes, and metabolic syndrome all become increasingly significant, though not necessarily strong in magnitude.Conclusion: Most putative correlates of T are replicated. There is a basis here for the generalization that among older men, those healthy have higher T than those who are not, but not a lot higher.

Testosterone Replacement Therapy: A Narrative Review with a Focus on New Oral Formulations

Male hypogonadism affects 10-30% of the male population and is often under-recognized and under-treated. Different replacement formulations exist, each with specific benefits and limitations. These replacements include gels, patches and short- and long-acting injectables. JATENZO® (oral testosterone undecanoate; Clarus Therapeutics Inc., Northbrook, IL, US) is the first oral formulation of testosterone approved by the US Food and Drug Administration. TLANDO® (oral testosterone undecanoate; Lipocine Inc., Salt Lake City, UT, US), another oral testosterone formulation, has also recently been approved by the US Food and Drug Administration. Based on unique chemistry using a self-emulsifying drug delivery system and lymphatic absorption, JATENZO and TLANDO address some of the limitations of other dosing routes while providing a safe option without evidence of liver dysfunction. This review discusses various testosterone treatment options, focusing on the role and pharmacokinetics of the new oral formulations.

Additive damage in the thromboxane related vasoconstriction and bradykinin relaxation of intramural coronary resistance arterioles in a rodent model of andropausal hypertension

Hypertension and andropause both accelerate age–related vascular deterioration. We aimed to evaluate the effects of angiotensin-II induced hypertension and deficiency of testosterone combined regarding the resistance coronaries found intramurally.

Four male groups were formed from the animals: control group (Co, n = 10); the group that underwenr orchidectomy (ORC, n = 13), those that received an infusion of angiotensin-II (AII, n = 10) and a grous that received AII infusion and were also surgically orchidectomized (AII + ORC, n = 8). AII and AII + ORC animals were infused with infusing angiotensin-II (100 ng/min/kg) using osmotic minipumps. Orchidectomy was perfomed in the ORC and the AII + ORC groupsto establish deficiency regarding testosterone. Following four weeks of treatment, pressure-arteriography was performed in vitro, and the tone induced by administration of thromboxane-agonist (U46619) and bradykinin during analysis of the intramural coronaries (well-known to be resistance arterioles) was studied.

U46619-induced vasoconstriction poved to be significantly decreased in the ORC and AII + ORC groups when compared with Co and AII animals. In ORC and AII + ORC groups, the bradykinin-induced relaxation was also significantly reduced to a greater extent compared to Co and AII rats. Following orchidectomy, the vasocontraction and vasodilatation capacity of blood vessels is reduced. The effect of testosterone deficiency on constrictor tone and relaxation remains pronounced even in AII hypertension: testosterone deficiency further narrows adaptation range in the double noxa (AII + ORC) group. Our studies suggest that vascular changes caused by high blood pressure and testosterone deficiency together may significantly increase age-related cardiovascular risk.

Testosterone replacement therapy and cardiovascular disease

The use of testosterone therapy has a complex history of apprehension and questions regarding its safety. Despite an eventual consensus that testosterone therapy was safe and effective, several studies relating to cardiovascular risks emerged in the last decade, rekindling skepticism regarding the safety of testosterone therapy. Given the utility of testosterone therapy in treating the symptoms of hypogonadism, it remains crucial to closely examine the safety of testosterone therapy. The present article synthesizes the current evidence regarding cardiovascular risks that may be associated with testosterone therapy, the potential mechanisms regarding testosterone's efficacy, and future directions in evaluating the safety of its use.

Testosterone deficiency in male organ transplant recipients

Testosterone deficiency is known to affect men with increasing incidence throughout their lifespan. The clinical manifestations of testosterone deficiency, in turn, negatively impact men's quality of life and perception of overall health. The interaction of chronic systemic disease and androgen deficiency represent an area for potential intervention. Here, we explore the topic of testosterone deficiency amongst men with end-stage organ failure requiring transplantation in order to elucidate the underlying pathophysiology of androgen deficiency of chronic disease and discuss whether intervention, including testosterone replacement and organ transplantation, improve patients' outcomes and quality of life.

The Roles of Androgens in Humans: Biology, Metabolic Regulation and Health

Androgens are an important and diverse group of steroid hormone molecular species. They play varied functional roles, such as the control of metabolic energy fate and partition, the maintenance of skeletal and body protein and integrity and the development of brain capabilities and behavioral setup (including those factors defining maleness). In addition, androgens are the precursors of estrogens, with which they share an extensive control of the reproductive mechanisms (in both sexes). In this review, the types of androgens, their functions and signaling are tabulated and described, including some less-known functions. The close interrelationship between corticosteroids and androgens is also analyzed, centered in the adrenal cortex, together with the main feedback control systems of the hypothalamic-hypophysis-gonads axis, and its modulation by the metabolic environment, sex, age and health. Testosterone (T) is singled out because of its high synthesis rate and turnover, but also because age-related hypogonadism is a key signal for the biologically planned early obsolescence of men, and the delayed onset of a faster rate of functional losses in women after menopause. The close collaboration of T with estradiol (E2) active in the maintenance of body metabolic systems is also presented Their parallel insufficiency has been directly related to the ravages of senescence and the metabolic syndrome constellation of disorders. The clinical use of T to correct hypoandrogenism helps maintain the functionality of core metabolism, limiting excess fat deposition, sarcopenia and cognoscitive frailty (part of these effects are due to the E2 generated from T). The effectiveness of using lipophilic T esters for T replacement treatments is analyzed in depth, and the main problems derived from their application are discussed.

Effect of High Testosterone Levels on Endothelial Function in Aorta and Erectile Function in Rats

BACKGROUND

Testosterone is an important hormone for the physical and mental health of men; however testosterone administration has also been suggested to adversely affect the cardiovascular system.

AIM

To investigate the effects of excessive testosterone administration on vascular endothelial and erectile function in rats.

METHODS

A total of seventy-five 12-week-old rats were divided into the following groups: Sham, castrated (Cast), castrated with subcutaneous administration of 100 mg/kg/month testosterone (Cast + T1), and castrated with subcutaneous administration of 100 mg/kg/week testosterone (Cast + T4). To observe the changes in testosterone level after the administration, rats were further divided into the following groups: control; T(6.25), wherein the rats were subcutaneously injected with 6.25 mg/kg testosterone; T(25) per week, wherein the rats were subcutaneously injected with 25 mg/kg testosterone per week; and T(100), wherein the rats were subcutaneously injected with 100 mg/kg testosterone per week. The relaxation responses of aorta were measured in these rats using standardized methods, and their erectile function was also evaluated. Statistical analysis of the obtained data was performed using two-way analysis of variance (ANOVA), Tukey-Kramer's multiple comparison test, or Student's t-test.

OUTCOMES

At the end of the study period, endothelial function was evaluated through measurement of isometric tension, while erectile function was assessed using intracavernosal pressure (ICP), mean arterial pressure (MAP), and the expression of endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), sirtuin 1 (Sirt1) and vascular endothelial growth factor A.

RESULTS

The ICP/MAP ratio in the Cast group (0.42 ± 0.04) was significantly lower than that in the Sham group (0.79 ± 0.07). The ICP/MAP ratio in the Cast + T1 group (0.73 ± 0.06) was significantly higher than that in the Cast group (P < .01) and that of the Cast + T4 (0.38 ± 0.01) group was unchanged (P > .05). The T(25) and T(100) groups exhibited significantly lower responses to ACh than the control group at 4 weeks (P < .01). Meanwhile, the ICP/MAP ratios in the T(25) group (0.44 ± 0.07) and T(100) group (0.47 ± 0.03) were significantly lower than that in the control group (0.67 ± 0.05) at stimulation frequencies of 16 Hz (P < .05). The expression of androgen receptor, Sirt1, and eNOS were significantly lower while that of iNOS was higher in the T(25) group compared with the control group (P < .05).

CLINICAL TRANSLATION

The results based on this animal model indicate that extremely high testosterone levels may affect endothelial and erectile function.

STRENGTHS AND LIMITATIONS

We found that high-dose testosterone administration decreased endothelial function in aorta and erectile function in rats. A major limitation of this study is that the blood concentration may not be representative of that in humans, and further research is needed.

CONCLUSION

The findings suggest that high doses of testosterone may cause endothelial dysfunction in the aorta and erectile dysfunction in rats and that the blood concentration should be monitored after testosterone administration. Kataoka T, Fukamoto A, Hotta Y, et al. Effect of High Testosterone Levels on Endothelial Function in Aorta and Erectile Function in Rats. Sex Med 2022;10:100550.

Management of male sexual dysfunction after cancer treatment

BACKGROUND

With an increase in the number of cancer survivors each year, male sexual dysfunction becomes an important topic for discussion between patients and providers who treat cancer. The aim of this article is to review types and mechanisms of sexual dysfunction after cancer therapy and discuss treatment options.

METHODS

Contemporary concepts regarding male sexual dysfunction after cancer treatment are reviewed and translated for clinical utility.

FINDINGS

To optimize recovery of erectile capacity after erectile dysfunction causing cancer treatments, a penile rehabilitation protocol involving phosphodiesterase inhibitors, vacuum erection device, intra corporal injections, or a combination is likely to provide some degree of clinically significant benefit. Treating hypogonadism post cancer treatment depends on the type of cancer that has been treated and patient comorbidities. Anejaculation after cancer treatments is typically not successfully or reliably treated due to the mechanism and severity of sympathetic nerve injury. Semen cryopreservation prior to cancer treatments that may injure nerve fibers essential for the ejaculatory response is highly recommended.

CONCLUSION

Management of post cancer treatment sexual dysfunction requires identification of this problem and referral to a specialist if necessary. There are several management options available that can greatly enhance quality of life in this often overlooked aspect of post cancer treatment care.

Improving the annual monitoring rates of testosterone replacement therapy patients in primary care

Introduction

Testosterone replacement therapy (TRT) is the treatment of choice for male hypogonadism. British Society for Sexual Medicine (BSSM) guidelines on adult testosterone deficiency recommend that TRT patients undergo annual monitoring of their testosterone levels and potential complications of treatment; though evidence suggests that substantial numbers of men on TRT are not monitored adequately.

Methods

Review of the electronic patient record from a single general practice in southwest Scotland revealed that only 1 of 26 (4%) TRT patients had been monitored as per BSSM guidelines in the previous 12 months. Additionally, when monitoring was undertaken there was inconsistency in the blood tests requested. The use of quality improvement (QI) tools including process mapping and cause-and-effect diagram identified staff and patient knowledge of monitoring requirements and the lack of an effective recall system as areas for improvement. We tested three change ideas: the utilisation of an existing recall system for long-term therapies; a TRT Ordercomms blood group template (OBGT) to standardise monitoring; and a patient information leaflet (PIL) to improve patient education. The aim of this project was to achieve 60% annual monitoring rate.

Results

The percentage of patients monitored for testosterone levels and potential TRT complications increased from 4% (1/26) to 65% (17/26) over a 7-week test period. The utilisation of the existing recall system was a particularly effective intervention, leading to an increase from 4% (1/26) to 31% (8/26) in the first 2 weeks.

Conclusion

The use of QI tools was associated with over 60% of male TRT patients receiving comprehensive annual monitoring, as per BSSM guidelines. Our findings support the hypothesis that a patient recall system, combined with an OBGT and a PIL led to this increase.

[Testosterone and congestive heart failure]

This article summarizes current information about the interrelation between testosterone concentrations and chronic heart failure (CHF). The authors described key publications that address the prevalence of testosterone deficiency in patients with CHF, the effect of endogenous and exogenous testosterone on the cardiovascular system, the relationship between testosterone levels and the severity and prognosis of CHF, and the efficacy of interventional treatments for CHF.

The relationship between serum sex hormone and cardiac echocardiographic findings in healthy men

Serum sex hormones are known to be associated with cardiovascular disease (CVD), but effects in healthy men on cardiac function have not been well quantified. The authors sought to evaluate an association of sex hormones with cardiac structure and function. Study participants were 857 Korean men without significant cardiovascular diseases participating in the Healthy Twin Study. We estimated the associations of total testosterone (TT) and sex hormone-binding globulin (SHBG) with cardiac structure and function measured by echocardiography using a linear mixed regression model with consideration of random and fixed effects of covariates. The ratio of peak early diastolic velocity of mitral inflow over peak early diastolic mitral annular velocity (E/e') and left atrial volume index (LAVI), functional parameters reflecting left ventricle (LV) filling pressure, were inversely associated with TT even after further cross-adjustment for SHBG level. There was a positive association between LAVI and SHBG, regardless of TT adjustment. These findings suggest that serum testosterone level is positively associated with LV diastolic function independent of SHBG level.

Nestin-dependent mitochondria-ER contacts define stem Leydig cell differentiation to attenuate male reproductive ageing

Male reproductive system ageing is closely associated with deficiency in testosterone production due to loss of functional Leydig cells, which are differentiated from stem Leydig cells (SLCs). However, the relationship between SLC differentiation and ageing remains unknown. In addition, active lipid metabolism during SLC differentiation in the reproductive system requires transportation and processing of substrates among multiple organelles, e.g., mitochondria and endoplasmic reticulum (ER), highlighting the importance of interorganelle contact. Here, we show that SLC differentiation potential declines with disordered intracellular homeostasis during SLC senescence. Mechanistically, loss of the intermediate filament Nestin results in lower differentiation capacity by separating mitochondria-ER contacts (MERCs) during SLC senescence. Furthermore, pharmacological intervention by melatonin restores Nestin-dependent MERCs, reverses SLC differentiation capacity and alleviates male reproductive system ageing. These findings not only explain SLC senescence from a cytoskeleton-dependent MERCs regulation mechanism, but also suggest a promising therapy targeting SLC differentiation for age-related reproductive system diseases.

The regulatory mechanisms contributing to male reproductive ageing are unknown. Here, the authors show that Nestin-dependent mito-ER contacts (MERCs) regulate stem Leydig cell (SLC) senescence and provide insights into SLCs-targeting therapies.

Potential Channeling Bias in the Evaluation of Cardiovascular Risk: The Importance of Comparator Selection in Observational Research

Background

Comparator selection is an important consideration in the design of observational research studies that evaluate potential associations between drug therapies and adverse event risks. It can affect the validity of observational study results, and potentially impact data interpretation, regulatory decision making, and patient medication access.

Objective

The aim of this study was to assess the impact of comparator selection bias using two real-world case studies evaluating an increased rate of acute myocardial infarction (AMI).

Methods

Data from the Truven Health Analytics MarketScan^® electronic medical claims database were used to conduct two retrospective observational cohort studies, utilizing a cohort new-user design, comparing AMI risk between testosterone replacement therapy (TRT) and phosphodiesterase-5 inhibitors (PDE5is) in men treated for hypogonadism, and triptans versus other prescribed acute treatments for migraine in adults. All patients were enrolled continuously in a health plan (no enrollment gap > 31 consecutive days) for ≥ 1 year before index. Baseline period was defined as 365 days prior to index. Exposure was defined by prescription and outcome of interest was defined as occurrence of AMI. Using Cox proportional hazard models, primary analysis for the TRT cohort compared AMI risk between propensity score (PS)-matched TRT-treated and untreated patients; secondary analysis evaluated risk between PS-matched TRT-treated and PDE5i-treated patients. For the triptan cohort, primary analysis compared AMI/ischemic stroke risk between PS-matched triptan-treated and opiate-treated patients; secondary analysis evaluated risk between PS-matched triptan-treated and nonsteroidal anti-inflammatory drug (NSAID)-treated patients and PS-matched non-prescription-treated migraine patients and general patients.

Results

No significant association between TRT and AMI was observed among TRT-treated (N = 198,528, mean age 52.4 ± 11.4 years) versus PDE5i-treated men (N = 198,528, mean age 52.3 ± 11.5 years) overall (adjusted hazard ratio [aHR] 1.01; 95% CI 0.95–1.07; p = 0.80). Among patients with prior cardiovascular disease (CVD), risk of AMI was significantly increased for TRT-treated versus PDE5i-treated patients (aHR 1.13; 95% CI 1.03–1.25). The triptan study included three comparisons (triptans [N = 436,642] vs prescription NSAIDs [N = 334,152], opiates [N = 55,234], and untreated migraine [N = 1,168,212]), and a positive control (untreated vs general non-migraine patients [N = 11,735,009]). Analyses of MI risk in migraine patients prescribed triptans versus NSAIDs/opiates had mixed results: the point estimate ranged from 0.33 to 0.84 depending on chosen study window.

Conclusions

Cardiovascular outcomes were not worse in hypogonadism patients with TRT versus PDE5i; however, a potential association with AMI was found in patients with prior CVD receiving TRT versus PDE5i. Findings pointed to a pseudo-protective effect of triptans versus untreated migraine patients or those potentially older and less healthy patients exposed to prescription NSAIDs or opiates. Triptan users should not be compared with those using other anti-migraine prescriptions when evaluating cardiovascular outcomes in migraine patients. Presence of high cardiovascular risks may contribute to channeling bias—healthier subjects being selected to receive treatment—highlighting the importance of choosing comparators wisely in observational studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40290-022-00433-z.

Morbidity and mortality in men: Role of androgens

In this narrative review we provide an overview of the current literature on male hypogonadism and related comorbidities, also depicting the role of testosterone therapy (TTh) in the various settings. Male hypogonadism has been associated with major comorbidities such as type 2 diabetes mellitus, obesity and cardiovascular diseases, promoting a vicious cycle that may lead to further hypogonadism. The biological underpinnings of this association are currently under investigations, but clearly emerges the relevance of the hypothalamic-pituitary-gonadal axis. Hypogonadism has also been associated with increased risk of mortality. As such, TTh has the potential to oppose these patterns and improve cardiovascular and metabolic health in hypogonadal men. Clinical and observational data suggest that in males with hypogonadism, TTh, together with lifestyle changes and diabetes medications, may improve glycemia, reduce risk of progression to diabetes and provides positive effects on cardiovascular risk. Conversely, available data does not fully support any increased risk of prostate cancer in men under TTh. Of clinical relevance, a possible harmful role of hypogonadal status in men with COVID-19 eventually emerged.