Testosterone replacement therapy improves insulin resistance, glycaemic control, visceral adiposity and hypercholesterolaemia in hypogonadal men with type 2 diabetes

Novel perspectives of testosterone therapy in men with functional hypogonadism: traversing the gaps of knowledge

INTRODUCTION

In the past decade, there has been a significant augmentation in the corpus of evidence pertaining to functional hypogonadism. Despite this, prevailing clinical guidelines continue to advise against the universal screening for hypogonadism in middle-aged and elderly males.

FINDINGS

Numerous randomized controlled trials have scrutinized the effects of testosterone therapy in males afflicted with type 2 diabetes and/or obesity. However, these guidelines uniformly assert that lifestyle modifications and weight reduction should be the primary intervention strategies in overweight and obese males, relegating testosterone therapy to a secondary, selective option. It is extensively documented that testosterone therapy can yield substantial improvements in various metabolic parameters as well as ameliorate symptoms of erectile dysfunction. Moreover, recent studies have demonstrated the potential of testosterone therapy in reversing type 2 diabetes in males with low-normal testosterone levels who are at elevated risk for this condition, in comparison to the outcomes achievable through lifestyle modifications alone.

CONCLUSION

This focused review article aims to present a comprehensive update on the latest data concerning the innovative aspects of testosterone therapy in males with functional hypogonadism, particularly in the context of type 2 diabetes and/or obesity. Additionally, it will delve into the cardiovascular safety of such interventions within this high-risk demographic, with a special emphasis on insights gleaned from the TRAVERSE trial.

Diagnosing and treating the elderly individual with hypopituitarism

Hypopituitarism in the elderly is an underestimated condition mainly due to the non-specific presentation that can be attributed to the effects of aging and the presence of comorbidities. Diagnosis and treatment of hypopituitarism often represent a challenging task and this is even more significant in the elderly. Diagnosis can be insidious due to the physiological changes occurring with aging that complicate the interpretation of hormonal investigations, and the need to avoid some provocative tests that carry higher risks of side effects in this population. Treatment of hypopituitarism has generally the goal to replace the hormonal deficiencies to restore a physiological balance as close as possible to that of healthy individuals but in the elderly this must be balanced with the risks of over-replacement and worsening of comorbidities. Moreover, the benefit of some hormonal replacement therapies in the elderly, including sex hormones and growth hormone, remains controversial.

Association of sex hormones with non-alcoholic fatty liver disease: An observational and Mendelian randomization study

BACKGROUND AND AIMS

Sex-specific associations of sex hormone-binding globulin (SHBG) and bioavailable testosterone (BAT) with NAFLD remain indeterminate. We aimed to explore observational and genetically determined relationships between each hormone and NAFLD.

METHODS

We included 187 395 men and 170 193 women from the UK Biobank. Linear and nonlinear Cox regression models and Mendelian randomization (MR) analysis were used to test the associations.

RESULTS

During 12.49 years of follow-up, 2209 male and 1886 female NAFLD cases were documented. Elevated SHBG levels were linearly associated with a lower risk of NAFLD in women (HR (95% CI), .71 (.63, .79)), but not in men (a "U" shape, pnon-linear < .001). Higher BAT levels were associated with a lower NAFLD risk in men (HR (95% CI), .81 (.71, .93)) but a higher risk in women (HR (95% CI): 1.25 (1.15, 1.36)). Genetically determined SHBG and BAT levels were linearly associated with NAFLD risk in women (OR (95% CI): .57 (.38, .87) and 2.21 (1.41, 3.26) respectively); in men, an "L-shaped" MR association between SHBG levels and NAFLD risk was found (pnon-linear = .016). The bidirectional MR analysis further revealed the effect of NAFLD on SHBG and BAT levels in both sexes.

CONCLUSIONS

Consistently, linear associations of lower SHBG and higher BAT levels with increased NAFLD risk were both conventionally and genetically found in women, while in men, SHBG acts in a nonlinear manner. In addition, NAFLD may affect SHBG and BAT levels.

Cardiovascular safety of testosterone replacement therapy in men: an updated systematic review and meta-analysis

INTRODUCTION

The cardiovascular (CV) safety of testosterone (T) replacement therapy (TRT) is still conflicting. Recent data suggested a TRT-related increased risk of atrial fibrillation (AF). The aim of this study was to systematic review and meta-analyze CV risk related to TRT as derived from placebo controlled randomized trials (RCTs).

AREAS COVERED

An extensive Medline, Embase, and Cochrane search was performed. All placebo-controlled RCTs reporting data on TRT-related CV safety were considered. To better analyze the role of T on AF, population-based studies investigating the relationship between endogenous circulating T levels and AF incidence were also included and analyzed.

EXPERT OPINION

Out of 3.615, 106 studies were considered, including 8.126 subjects treated with TRT and 7.310 patients allocated to placebo. No difference between TRT and placebo was observed when major adverse CV events were considered. Whereas the incidence of non-fatal arrhythmias and AF was increased in the only trial considering CV safety as the primary endpoint, this was not confirmed when all other studies were considered (MH-OR 1.61[0.84;3.08] and 1.44[0.46;4.46]). Similarly, no relationship between endogenous T levels and AF incidence was observed after the adjustment for confounders Available data confirm that TRT is safe and it is not related to an increased CV risk.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

Mapping the landscape of research on insulin resistance: a visualization analysis of randomized clinical trials

BACKGROUND

Insulin resistance, a condition in which cells do not respond adequately to insulin, plays a crucial role in diabetes and related metabolic disorders. Randomized clinical trials (RCTs) explore interventions to manage insulin resistance, contributing to evidence-based medical progress. The current study aimed to analyze the global research landscape and trends in RCTs targeting insulin resistance.

METHODS

This study used bibliometric analysis and data visualization to examine RCT publications on insulin resistance from 2003 to 2022. The Scopus database was used due to its comprehensive coverage. The search strategy involved combining terms related to insulin resistance with RCT-related terms. The search query was validated, and core bibliometric indicators were used to analyze publication growth, origin, productivity, quality, and citations.

RESULTS

Between 2003 and 2022, 1077 RCT-focused publications on insulin resistance were identified from a pool of 24,932 related articles. The growth followed two phases, with a significant increase after 2008. The USA (n = 308; 28.60%), Iran (n = 165; 15.32%), China (n = 110; 10.21%), and the UK (n = 92; 8.54%) were the main contributors. The active institutions included Tehran University of Medical Sciences (n = 38; 3.53%) and Harvard Medical School (n = 31; 2.88%). Prominent funding agencies include the National Institutes of Health (n = 88; 8.17%) and the National Institute of Diabetes and Digestive and Kidney Diseases (n = 86; 7.99%). The top journals included the American Journal of Clinical Nutrition (n = 44; 4.09%) and Diabetes Care (n = 35; 3.25%). Co-occurrence analysis revealed three clusters addressing "utilizing lipid panels as indicators of insulin resistance," "analyzing the impact of diet composition and physical activity on insulin sensitivity among obese individuals," and "exploring insulin resistance in cases of polycystic ovary syndrome."

CONCLUSIONS

This comprehensive bibliometric analysis highlights the global research landscape and trends in RCTs targeting insulin resistance. Research on lipid panels, diet impact, and insulin resistance in patients with polycystic ovary syndrome will continue to be a hotspot. The findings offer valuable information on research priorities, international collaborations, and impactful publications. This study provides a foundation for future directorial investigations in this critical area of metabolic health.

Adult Male Hypogonadism: A Laboratory Medicine Perspective on Its Diagnosis and Management

Testosterone (T), the principal androgen secreted by the testes, plays an essential role in male health. Male hypogonadism is diagnosed based on a combination of associated clinical signs and symptoms and laboratory confirmation of low circulating T levels. In this review, we have highlighted factors, both biological and analytical, that introduce variation into the measurement of serum T concentrations in men; these need to be considered when requesting T levels and interpreting results. There is an ongoing need for analytical standardisation of T assays and harmonisation of pre- and post-analytical laboratory practices, particularly in relation to the laboratory reference intervals provided to clinicians. Further, there is a need to share with service users the most up-to-date and evidence-based action thresholds for serum T as recommended in the literature. Estimation of free testosterone may be helpful. Causes of secondary hypogonadism should be considered. A comprehensive approach is required in the management of male hypogonadism, including lifestyle modification as well as medication where appropriate. The goal of treatment is the resolution of symptoms as well as the optimisation of metabolic, cardiovascular, and bone health. The advice of an endocrinologist should be sought when there is doubt about the cause and appropriate management of the hypogonadism.

Sex differences in chronic liver disease and benign liver lesions

The epidemiology, natural history, and therapeutic responses of chronic liver diseases and liver lesions often vary by sex. In this review, we summarize available clinical and translational data on these aspects of the most common liver conditions encountered in clinical practice, including the potential contributions of sex hormones to the underlying pathophysiology of observed differences. We also highlight areas of notable knowledge gaps and discuss sex disparities in access to liver transplant and potential strategies to address these barriers. Given established sex differences in immune response, drug metabolism, and response to liver-related therapies, emerging clinical trials and epidemiological studies should prioritize dedicated analyses by sex to inform sex-specific approaches to liver-related care.

Insulin Resistance and Hypertension: Mechanisms Involved and Modifying Factors for Effective Glucose Control

Factors such as aging, an unhealthy lifestyle with decreased physical activity, snacking, a standard Western diet, and smoking contribute to raising blood pressure to a dangerous level, increasing the risk of coronary artery disease and heart failure. Atherosclerosis, or aging of the blood vessels, is a physiological process that has accelerated in the last decades by the overconsumption of carbohydrates as the primary sources of caloric intake, resulting in increased triglycerides and VLDL-cholesterol and insulin spikes. Classically, medications ranging from beta blockers to angiotensin II blockers and even calcium channel blockers were used alone or in combination with lifestyle modifications as management tools in modern medicine to control arterial blood pressure. However, it is not easy to control blood pressure or the associated complications. A low-carbohydrate, high-fat (LCHF) diet can reduce glucose and insulin spikes, improve insulin sensitivity, and lessen atherosclerosis risk factors. We reviewed articles describing the etiology of insulin resistance (IR) and its impact on arterial blood pressure from databases including PubMed, PubMed Central, and Google Scholar. We discuss how the LCHF diet is beneficial to maintaining arterial blood pressure at normal levels, slowing down the progression of atherosclerosis, and reducing the use of antihypertensive medications. The mechanisms involved in IR associated with hypertension are also highlighted.

Temporal trends in mortality of tuberculosis attributable to high fasting plasma glucose in China from 1990 to 2019: a joinpoint regression and age-period-cohort analysis

Background

Nowadays, high fasting plasma glucose (HFPG) has been identified as the important risk factor contributing to the increased burden of diseases. But there remains a lack of research on tuberculosis (TB) mortality specifically attributable to HFPG. Thus, this study aims to explore the long-term trends in HFPG-related TB mortality in China from 1990 to 2019.

Methods

Data on HFPG-related TB mortality were obtained from the Global Burden of Disease (GBD) Study 2019. Analyzing the data using joinpoint regression and age-period-cohort methods adjusting for age, period, and cohort allowed us to assess the trends in TB mortality due to HFPG.

Results

The age-standardized mortality rates (ASMRs) of TB attributable to HFPG exhibited a downward trend in China from 1990 to 2019, with an average annual percentage change (AAPC) of -7.0 (95% CI, -7.5 to -6.6). Similar trends were found for male (AAPC of -6.5 [95% CI, -7.0 to -6.0]) and female (AAPC of -8.2 [95% CI, -8.5 to -7.9]), respectively. Local drifts curve with a U-shaped pattern reflected the AAPC of TB mortality due to HFPG across age groups. The greatest decline was observed in the age group of 60-64 years. The mortality rates related to HFPG first increased and then decreased with increasing age, peaking in the 55-59 age group. Our analysis of the period and cohort effects found that the rate ratios of TB mortality due to HFPG have decreased over the past three decades, more prominently in women. It is noteworthy that while both genders have seen a decline in HFPG-attributable TB mortality and risk, men have a higher risk and slightly less significant decline than women.

Conclusion

The present study shows that HFPG-related ASMRs and risk of TB in China decreased over the last 30 years, with similar trends observed in both men and women. In order to attain the recommended level set by the WHO, the effective strategies for glycemic control and management still needed to be implemented strictly to further decrease the burden of TB.

Biomarkers to Be Used for Decision of Treatment of Hypogonadal Men with or without Insulin Resistance

Male hypogonadism is a result of low testosterone levels, but patients could be insulin-sensitive (IS) or insulin-resistant (IR), showing different impaired metabolic pathways. Thus, testosterone coadministration, which is commonly used to reestablish testosterone levels in hypogonadism, must take into account whether or not insulin is still active. By comparing metabolic cycles recorded in IS and IR plasma before and after testosterone therapy (TRT), it is possible to know what metabolic pathways can be reactivated in the two different groups upon testosterone recovery, and it is possible to understand if antagonism or synergy exists between these two hormones. IS hypogonadism uses glycolysis, while IR hypogonadism activates gluconeogenesis through the degradation of branched-chain amino acids (BCAAs). Upon administration of testosterone, acceptable improvements are observed in IS patients, wherein many metabolic pathways are restored, while in IR patients, a reprogramming of metabolic cycles is observed. However, in both subgroups, lactate and acetyl-CoA increases significantly. In IS patients, lactate is used through the glucose-lactate cycle to produce energy, while in IR patients, both lactate and acetyl-CoA are metabolized into ketone bodies, which are used to produce energy. Thus, in IR patients, an ancestral molecular mechanism is activated to produce energy, mimicking insulin effects. Regarding lipids, in both groups, the utilization of fatty acids for energy (β-oxidation) is blocked, even after TRT; free fatty acids (FFAs) increase in the blood in IS patients, while they are incorporated into triglycerides in those with IR. In both subgroups of hypogonadism, supplementation of useful chemicals is recommended during and after TRT when metabolites are not restored; they are listed in this review.

Treatment with Testosterone Therapy in Type 2 Diabetic Hypogonadal Adult Males: A Systematic Review and Meta-Analysis

Testosterone replacement therapy (TRT) has been used to treat hypogonadal males with type 2 diabetes mellitus (T2DM) for a long time, despite variable results. This meta-analysis examines TRT's role in hypogonadal males with T2DM. The databases PubMed, Embase, and Google Scholar were searched for relevant RCTs and observational studies. Estimated pooled mean differences (MDs) and relative risks with 95% confidence intervals were used to measure the effects of TRT (CIs). When compared to the placebo, TRT improves glycemic management by significantly reducing glycated hemoglobin (HBA1c) levels (WMD = -0.29 [-0.57, -0.02] p = 0.04; I2 = 89.8%). Additionally, it reduces the homeostatic model assessment levels of insulin resistance (WMD = -1.47 [-3.14, 0.19]; p = 0.08; I2 = 56.3%), fasting glucose (WMD = -0.30 [-0.75, 0.15]; p = 0.19; I2 = 84.4%), and fasting insulin (WMD = -2.95 [-8.64, 2.74]; however, these results are non-significant. On the other hand, HBA1c levels are significantly reduced with TRT; in addition, total testosterone levels significantly increase with testosterone replacement therapy (WMD = 4.51 [2.40, 6.61] p = 0.0001; I2 = 96.3%). Based on our results, we hypothesize that TRT can improve glycemic control and hormone levels, as well as lower total cholesterol, triglyceride, and LDL cholesterol levels while raising HDL cholesterol in hypogonadal type 2 diabetes patients. To this end, we recommend TRT for these patients in addition to standard diabetes care.

Cardiometabolic indices predict hypogonadism in male patients with type 2 diabetes

PURPOSE

To evaluate in men with type 2 diabetes the association of cardiometabolic indices [Visceral Adiposity Index (VAI), Triglyceride Glucose Index (TyG), and lipid accumulation product (LAP)] with total testosterone (TT) levels, and their predictive cut-off values in identifying hypogonadism.

METHODS

265 consecutive men aged 40-70 years with type 2 diabetes performed an andrological evaluation; metabolic parameters and TT were determined. Receiver operating characteristic (ROC) curves were used to identify cut-off values of cardiometabolic indices in predicting low testosterone (TT < 12 nmol/l).

RESULTS

VAI, TyG, and LAP were negatively associated with TT levels. The prevalence of hypogonadism in men in the fourth quartiles of VAI, TyG, and LAP was ~ 70.0-75.0% compared to ~ 10.0-17.0% in men in the first quartiles (p < 0.001). The sensitivity and specificity of the three cardiometabolic indices in predicting TT < 12 nmol/l were significantly higher concerning BMI, waist circumference, lipid profile and HbA1c. Cut off values of VAI ≥ 3.985, TyG ≥ 4.925, and LAP ≥ 51.645 predict hypogonadism with good sensitivity and specificity.

CONCLUSION

This is the first study evaluating the association of VAI, TyG, and LAP with hypogonadism in men with type 2 diabetes. Alterations in these indices should direct the patients to andrological evaluation.

Treating Hypopituitarism in the Over 65s: Review of Clinical Studies

The current increase of life expectancy is associated with the presence of endocrine diseases in the elderly. The management of hypopituitarism in this group of patients is a challenging task. A correct diagnosis, which represents an essential requisite for an appropriate medical treatment, can be difficult because of the physiological changes occurring in pituitary function with aging, which may lead to challenges in the interpretation of laboratory results. Furthermore, the treatment requires several careful considerations: the need to restore the hormonal physiology with replacement therapies must be balanced with the need to avoid the risks of the over-replacement, especially in the presence of concomitant cardiovascular and metabolic disease. Interactions with other drugs able to modify the absorption and/or the metabolism of hormonal replacement therapies should be considered, in particular for the treatment of hypoadrenalism and hypothyroidism. The most important challenges stem from the lack of specific studies focused on the management of hypopituitarism in older people.

The role of androgens in pressure overload myocardial hypertrophy

Pressure overload hypertrophy of the left ventricle is a common result of many cardiovascular diseases. Androgens show anabolic effects in skeletal muscles, but also in myocardial hypertrophy. We carefully reviewed literature regarding possible effects of androgens on specific left ventricular hypertrophy in pressure overload conditions excluding volume overload conditions or generel sex differences.

Adult- and late-onset male hypogonadism: the clinical practice guidelines of the Italian Society of Andrology and Sexual Medicine (SIAMS) and the Italian Society of Endocrinology (SIE)

PURPOSE

To provide the evidence-based recommendations on the role of testosterone (T) on age-related symptoms and signs remains.

METHODS

The Italian Society of Andrology and Sexual Medicine (SIAMS) and the and the Italian Society of Endocrinology (SIE) commissioned an expert task force to provide an updated guideline on adult-onset male hypogonadism. Derived recommendations were based on Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.

RESULTS

Clinical diagnosis of adult-onset hypogonadism should be based on a combination of clinical and biochemical parameters. Testosterone replacement therapy (TRT) should be offered to all symptomatic subjects with hypogonadism after the exclusion of possible contraindications. T gels and the long-acting injectable T are currently available preparations showing the best efficacy/safety profile. TRT can improve all aspects of sexual function, although its effect is limited in more complicated patients. Body composition (reducing fat mass and increasing lean mass) is improved after TRT, either in subjects with or without metabolic syndrome or type 2 diabetes. Conversely, the role of TRT in improving glycometabolic control is more conflicting. TRT can result in increasing bone mineral density, particularly at lumbar site, but no information on fracture risk is available. Limited data support the use of TRT for improving other outcomes, including mood frailty and mobility.

CONCLUSIONS

TRT can improve sexual function and body composition particularly in less complicated adult and in aging subjects with hypogonadism. When hypogonadism is adequately diagnosed, T appropriately prescribed and subjects correctly followed up, no short-term increased risk of adverse events is observed. Longer and larger studies are advisable to better clarify TRT long-term efficacy/safety profile.

The HEAT-Registry (HEmatopoietic Affection by Testosterone): comparison of a transdermal gel vs long-acting intramuscular testosterone undecanoate in hypogonadal men

CONTEXT

Testosterone (T) therapy of hypogonadal men requires stable kinetics, tolerance and attenuation of symptoms. Both intramuscular injections of the long-acting ester T undecanoate (TU) and transdermal application of T gel offer a proven efficacy. As T has marked effects on hematopoiesis, an elevation of hematocrit has to be considered during T therapy.

OBJECTIVE

To compare the effects of a transdermal T gel with long-acting intramuscular TU on hematopoiesis, controlling for age, diagnosis, androgen receptor susceptibility and obesity.

DESIGN

Prospective two-arm open registry, minimum duration of 26 weeks per patient. Putative modulators of erythropoiesis entering regression models were type of medication, type of hypogonadism, delta of total testosterone concentrations, waist circumference, age as well as (in a sub-group) androgen receptor gene CAG repeat length.

SETTING

Tertiary university based andrological outpatient department.

PATIENTS

802 hypogonadal men, 498 receiving T gel and 304 receiving intramuscular TU, median age 40 years (interquartile range = 25).

RESULTS

Follow-up visits after initiation of treatment occurred between treatment weeks 26-30. Serum T concentrations increased markedly in both patient groups. Men receiving intramuscular TU exhibited an increased hematocrit (>50%) to a significantly higher amount than men receiving T gel (69/304 vs. 25/498, p < 0.001). Corresponding results were seen for higher values of hematocrit (>52% and >54%). Advanced age (p = 0.009), higher waist circumference (p = 0.01), higher delta testosterone (p = 0.007) and functional vs classical hypogonadism (p = 0.04) contributed to the effect in stepwise multiple regression models. Attenuated androgen action (longer androgen receptor CAG repeats) mitigated the effect (p = 0.01) in a subgroup of 574 patients. Men with anemia (hemoglobin ≤12.7 g/dl) were more likely to move out of the pathological range when receiving TU vs T gel (41/53 vs. 49/89 p = 0.01).

CONCLUSIONS

T substitution with intramuscular TU or T gel increase T concentrations effectively. Long-acting TU leads to a higher rate of hematocrit levels >50%, whilst at the same time it seems to be more efficient to ameliorate anemia in the subgroup of respectively affected hypogonadal patients . This applies especially to obese older men with functional hypogonadism.

Metabolomics of testosterone enanthate administration during severe-energy deficit

INTRODUCTION

Testosterone administration attenuates reductions in total body mass and lean mass during severe energy deficit (SED).

OBJECTIVES

This study examined the effects of testosterone administration on the serum metabolome during SED.

METHODS

In a double-blind, placebo-controlled clinical trial, non-obese men were randomized to receive 200-mg testosterone enanthate/wk (TEST) (n = 24) or placebo (PLA) (n = 26) during a 28-d inpatient, severe exercise- and diet-induced energy deficit. This study consisted of three consecutive phases. Participants were free-living and provided a eucaloric diet for 14-d during Phase 1. During Phase 2, participants were admitted to an inpatient unit, randomized to receive testosterone or placebo, and underwent SED for 28-d. During Phase 3, participants returned to their pre-study diet and physical activity habits. Untargeted metabolite profiling was conducted on serum samples collected during each phase. Body composition was measured using dual-energy X-ray absorptiometry after 11-d of Phase 1 and after 25-d of Phase 2 to determine changes in fat and lean mass.

RESULTS

TEST had higher (Benjamini-Hochberg adjusted, q < 0.05) androgenic steroid and acylcarnitine, and lower (q < 0.05) amino acid metabolites after SED compared to PLA. Metabolomic differences were reversed by Phase 3. Changes in lean mass were associated (Bonferroni-adjusted, p < 0.05) with changes in androgenic steroid metabolites (r = 0.42-0.70), acylcarnitines (r = 0.37-0.44), and amino acid metabolites (r = - 0.36-- 0.37). Changes in fat mass were associated (p < 0.05) with changes in acylcarnitines (r = - 0.46-- 0.49) and changes in urea cycle metabolites (r = 0.60-0.62).

CONCLUSION

Testosterone administration altered androgenic steroid, acylcarnitine, and amino acid metabolites, which were associated with changes in body composition during SED.

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.

[Testosterone treatment]

Male hypogonadism is a congenital or acquired disorder that exerts a negative influence on various organ functions and can massively impair the quality of life through the relative or absolute deficiency of testosterone. A variety of preparations are available for substitution treatment, which differ in administration form and intake interval. For the execution of testosterone treatment various guidelines exist with clear and practical instructions on the indications, contraindications, treatment procedure and monitoring. Of particular importance are cardiovascular aspects and diseases of the prostate gland, which underlines the central position of the urologist in the treatment.

On the Need to Distinguish between Insulin-Normal and Insulin-Resistant Patients in Testosterone Therapy

Male hypogonadism is a disorder characterized by low levels of the hormone testosterone and patients may also have insulin sensitivity (IS) or insulin resistance (IR), such that they show different clinical complications and different metabolic pathways. In this review, we compare metabonomic differences observed between these two groups before and after testosterone therapy (TRT) in order to obtain information on whether the two hormones testosterone and insulin are synergistic or antagonistic. IS hypogonadism uses glucose as the main biofuel, while IR activates gluconeogenesis by the degradation of branched-chain amino acids. The Krebs (TCA) cycle is active in IS but connected with glutaminolysis, while in IR the TCA cycle stops at citrate, which is used for lipogenesis. In both cases, the utilization of fatty acids for energy (β-oxidation) is hampered by lower amounts of acetylcarnitine, although it is favored by the absence of insulin in IR. Increased free fatty acids (FFAs) are free in the blood in IS, while they are partially incorporated in triglycerides in IR. Thus, upon TRT, the utilization of glucose is increased more in IS than in IR, revealing that in IR there is a switch from preferential glucose oxidation to lipid oxidation. However, in both cases, a high production of lactate and acetyl-CoA is the final result, with these levels being much higher in IR. Lactate is used in IS in the glucose–lactate cycle between the liver and muscle to produce energy, while in IR lactate and acetyl-CoA are biotransformed into ketone bodies, resulting in ketonuria. In conclusion, the restoration of testosterone values in hypogonadism gives better results in IS than in IR patients: in IS, TRT restores most of the metabolic pathways, while in IR TRT impairs insulin, and when insulin is inactive TRT activates an ancestral molecular mechanism to produce energy. This evidence supports the hypothesis that, over time, hypogonadism switches from IS to IR, and in the latter case most of the insulin-related metabolisms are not reactivated, at least within 60 days of TRT. However, testosterone therapy in both IS and IR might be of benefit given supplementation with metabolites that are not completely restored upon TRT, in order to help restore physiological metabolisms. This review underlines the importance of using a systems biology approach to shed light on the molecular mechanisms of related biochemical pathways involving insulin and testosterone.

Glycemic Variability in Subjects with Diabetes and Hypogonadism during Testosterone Replacement Treatment: A Pilot Study

Background: This is a proof of concept, as a pilot study, with the aim to evaluate continuous glucose monitoring metrics (CGM) in subjects with type 2 diabetes (T2DM), treated with nutritional therapy and metformin, before and after testosterone replacement therapy (TRT). Methods: In this longitudinal observational study, subjects affected by T2DM and starting TRT for documented ED and hypogonadism were enrolled. All subjects mounted a CGM system during the v0 visit, one week before the beginning of the TRT (week−1), during v2, four weeks after the start of TRT (week 4), and v4 (week 12). CGM was worn for about 144 h after each visit. Results: A total of seven patients, referring to our clinic for erectile dysfunction (ED), were studied (aged 63.3 ± 2.3 years). Mean (± standard deviation) total testosterone level was 2.3 ± 0.6 ng/mL at baseline. After TRT, total testosterone level was 4.6 ± 3.04 ng/mL at week 4 and 3.93 ± 4.67 ng/mL at week 12. No significant differences were observed in TIR, TAR, TBR, estimated HbA1c, AUC below, and AUC above limit during the intervention period. Conclusions: This is the first study evaluating the effects of TRT on daily glucose excursions in subjects with T2DM and hypogonadism. Though we did not find any significant difference in key CGM metrics during the 12 weeks of TRT, this study confirms the glycometabolic safety of the TRT even on the most novel standardized glycemic targets.

Effects of androgens on glucose metabolism

Type 2 diabetes (T2D) and obesity are common and associated with increased morbidity and mortality. Cross-sectional and longitudinal studies have demonstrated a clear association between T2D, obesity and reduced total testosterone concentration. This relationship becomes less significant or absent with correction for changes in body composition, supporting the notion that changes in body composition are mediating these effects. Moreover, this mediating effect of body composition changes is bi-directional, as evidenced by interventional studies of weight loss and testosterone treatment. On the one hand, in obese men, serum testosterone increases markedly with weight loss. On the other hand, testosterone improves body composition. This relationship is driven by multiple complex interaction between obesity and insulin resistance and the hypothalamic-pituitary-testicular axis, at all levels. Data from randomised control trials have demonstrated that intervention with testosterone therapy increases muscle mass and reduces adiposity. Most recently it has been shown that treatment with testosterone prevents progression of impaired glucose tolerance to T2D, or reverses newly diagnosed T2D beyond lifestyle intervention alone. At present there are insufficient safety data to support the use of testosterone for prevention of type 2 diabetes.

Ethnic differences in serum testosterone concentration among Malay, Chinese and Indian men: A cross-sectional study

OBJECTIVE

To investigate non-urological patients with multiple comorbidities for factors contributing towards differences in testosterone concentration in multiethnic Malaysian men.

DESIGN

An observational study.

PATIENTS

Sexually active men, ≥40 years, with no known urological problems, were recruited at the phlebotomy clinic at our centre.

MEASUREMENTS

A brief history along with latest fasting lipid profile and plasma glucose levels were obtained. An Aging Male Symptoms questionnaire was administered; waist circumference (WC) and serum testosterone concentration were measured.

STATSTICAL ANALYSIS

Analysis of testosterone concentration between Malay, Indian and Chinese men was performed. Statistical tests such as analysis of variance, χ² test, univariate and multivariable regression were performed. Any p < .05 was noted as statistically significant.

RESULTS

Among the 604 participants analysed, mean testosterone concentration was significantly lower in Malays (15.1 ± 5.9 nmol/L) compared to the Chinese (17.0 ± 5.9 nmol/L) and Indian (16.1 ± 6.5 nmol/L) participants. The mean WC was also found to be higher among the Malays (96.1 ± 10.9 cm) compared to Chinese (92.6 ± 9.6 cm) and Indians (95.6 ± 9.9 cm). Testosterone concentration tended to be lower with higher age, but this was not statistically significant (p > .05). In the multivariable analysis only Malay ethnicity, WC ≥ 90 cm and low high-density lipoprotein (HDL) were associated with lower testosterone concentration.

CONCLUSION

In this study, Malaysian men of Malay origin had lower testosterone concentration compared with Indian and Chinese men. WC and low HDL were also associated with lower testosterone concentrations.

Testosterone Deficiency as One of the Major Endocrine Disorders in Chronic Kidney Disease

Reduced testosterone concentration is nowadays thought to be one of the main endocrine disorders in chronic kidney disease (CKD). It is caused by the dysfunction of the hypothalamic-pituitary-gonadal axis. The role of testosterone is multifactorial. Testosterone is responsible not only for reproductive processes, but it is a hormone which increases bone and muscle mass, improves lipid profile, insulin sensitivity, erythropoiesis, reduces blood pressure, and ameliorates mood and perception. The implications of hypogonadism in CKD are infertility and loss of libido, reduction of muscle mass and strength, disorders in bone mineralization, the development of sarcopenia and protein energy wasting (PEW), progression of atherosclerosis, increased visceral adiposity, insulin resistance, and anaemia. Reduced testosterone serum concentrations in CKD are associated with increased mortality rate. Testosterone supplementation improves sexual functions, reduces the level of inflammatory markers and blood pressure, stimulates muscle protein synthesis, improves insulin sensitivity and lipid profile, and increases muscle mass, bone mineral density, and haemoglobin concentration. It positively affects mood and well-being. The modes of testosterone supplementation are intramuscular injections, subcutaneous pellets, and percutaneous methods—patches and gels. Successful kidney transplantation may improve gonadal function and testosterone production, however, half of men with low testosterone concentrations before kidney transplantation do not restore hormonal function.

Effects of testosterone therapy in adult males with hypogonadism and T2DM: A meta-analysis and systematic review

BACKGROUND AND AIMS

Testosterone supplementation therapy (TST) is a longstanding treatment for hypogonadal men with type 2 diabetes mellitus (T2DM), even though the benefits of TST are variable among trials. This meta-analysis was done to determine the specific role of TST in hypogonadal men with T2DM.

METHODS

PubMed, Embase, and Google Scholar were queried to discover eligible randomized controlled trials (RCTs) and observational studies. To quantify the specific effects of TST, we estimated pooled mean differences (MDs) and relative risks with 95% confidence intervals (CIs).

RESULTS

Our meta-analysis included 1596 hypogonadal T2DM subjects from 12 randomized controlled trials and one observational study. TST can significantly enhance glycemic control compared to placebo by decreasing homeostatic model assessment of insulin resistance (WMD = -1.55 [-2.65, -0.45]; p = 0.26; I2 = 20.2%), fasting glucose (WMD = -0.35 [-0.79, 0.10]; p = 0.07; I2 = 69.7%), fasting insulin (WMD = -2.88 [-6.12, 0.36]; p = In addition, TST can decrease cholesterol (WMD = -0.28 [-0.47, -0.09] p = 0.0008; I2 = 91%) and triglyceride (WMD = -0.23 [-0.43, -0.03] p = 0.03; I2 = 79.2%). Furthermore, Testosterone therapy is related to a significant rise in total testosterone levels (WMD = 5.08 [2.90, 7.26] p = 0.0002; I2 = 92.9%). Pooling of free testosterone levels indicated a larger increase in the patients who got TST than placebo (WMD = 81.21 [23.87, 138.54] p = 0.07; I2 = 70%).

CONCLUSION

Our findings suggested that TST can enhance glycemic control and hormone levels and reduce total cholesterol, triglyceride, LDL cholesterol whereas increase HDL cholesterol in hypogonadal T2DM patients. Therefore, in these patients, we propose TST alongside anti-diabetic treatment.

Plasma Metabonomics in Insulin-Resistant Hypogonadic Patients Induced by Testosterone Treatment

Hypogonadic subjects with insulin resistance (IR) showed different metabonomic profiles compared to normo-insulinemic subjects (IS). Testosterone replacement therapy (TRT) may have a different impact on the metabolisms of those with the presence or absence of insulin resistance. We evaluated the changes in the metabolism of IR hypogonadic patients before and after 60 days of TRT. The metabonomic plasma profiles from 20 IR hypogonadal patients were recorded using ultra-high-performance liquid chromatography (UHPLC) and high-resolution mass spectrometry (HRMS). Plasma metabolites, before and after 60 days of TRT, were compared. In hypogonadic patients, carnosine, which is important for improving performance during exercise, increased. Conversely, proline and lysine—amino acids involved in the synthesis of collagen—reduced. Triglycerides decreased and fatty acids (FFAs) increased in the blood as a consequence of reduced FFA β-oxidation. Glycolysis slightly improved, while the Krebs cycle was not activated. Gluconeogenesis (which is the main energy source for hypogonadal IR before TRT) stopped after treatment. As a consequence, lactate and acetyl CoA increased significantly. Both lactate and acetyl CoA were metabolized into ketone bodies which increased greatly, also due to leucine/isoleucine degradation. Ketone bodies were derived predominantly from acetyl CoA because the reaction of acetyl CoA into ketone bodies is catalyzed by mtHMGCoA synthase. This enzyme is inhibited by insulin, which is absent in IR patients but overexpressed following testosterone administration. Ketosis is an alternative route for energy supply and provides the same metabolic effects as insulin but at the metabolic or primitive control level, which bypasses the complex signaling pathway of insulin. After treatment, the hypogonadic patients showed clinical symptoms related to ketonuria. They presented similarly to those following a ketogenic diet, the so-called ‘keto flu’. This must be taken into account before the administration of TRT to hypogonadic patients.

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.

Effects of endocrine disorders on lipids and lipoproteins

Endocrine diseases may be associated with dyslipidaemia and may increase atherosclerotic cardiovascular disease (ASCVD) risk. This chapter describes changes in lipids and lipoproteins in diseases of the pituitary, thyroid, adrenal glands, ovaries, and testes, the mechanisms for these changes, ASCVD risk in these endocrine disorders, and whether treatment of the endocrine disorder improves the lipid profile and reduces ASCVD risk. Acromegaly, GH deficiency, Cushing syndrome, chronic glucocorticoid replacement, hypothyroidism, PCOS and male hypogonadism can increase LDL-C and/or TG. Marked reductions in LDL-C are associated with hyperthyroidism, and extremely low HDL-C levels with testosterone and/or other anabolic steroid abuse. Acromegaly, GH deficiency, Cushing syndrome, and chronic glucocorticoid replacement are associated with increased ASCVD risk. Treatment of acromegaly, GH deficiency, hypothyroidism, Cushing syndrome, and testosterone deficiency reduce LDL-C, although statin therapy may still be needed. Effects on ASCVD are not known.

Erectile dysfunction and diabetes: A melting pot of circumstances and treatments

Diabetes mellitus (DM), a chronic metabolic disease characterised by elevated levels of blood glucose, is among the most common chronic diseases. The incidence and prevalence of DM have been increasing over the years. The complications of DM represent a serious health problem. The long-term complications include macroangiopathy, microangiopathy and neuropathy as well as sexual dysfunction (SD) in both men and women. Erectile dysfunction (ED) has been considered the most important SD in men with DM. The prevalence of ED is approximately 3.5-fold higher in men with DM than in those without DM. Common risk factors for the development of DM and its complications include sedentary lifestyle, overweight/obesity and increased caloric consumption. Although lifestyle changes may help improve sexual function, specific treatments are often needed. This study aims to review the definition and prevalence of ED in DM, the impact of DM complications and DM treatment on ED and, finally, the current and emerging therapies for ED in patients with DM.

Baseline Testosterone Predicts Body Composition and Metabolic Response to Testosterone Therapy

CONTEXT

Male hypogonadism adversely affects body composition, bone mineral density (BMD), and metabolic health. A previous report showed that pre-treatment testosterone (T) levels of <200 ng/dl is associated with greater improvement in spine BMD with T therapy. However, to date, there is no study that investigates whether baseline T levels also influence body composition and metabolic response to T therapy.

OBJECTIVE

The aim of this study is to determine if there are differences in the changes in body composition, metabolic profile, and bone turnover markers, in addition to BMD, in response to T therapy in men with a baseline T level of <264 ng/dl compared to those with levels ≥264 ng/dl.

METHODS

This is a secondary analysis of a single-arm, open-label clinical trial (NCT01378299) on pharmacogenetics of response to T therapy conducted between 2011 and 2016 involving 105 men (40-74 years old), with average morning T < 300 ng/dl, given intramuscular T cypionate 200 mg every 2 weeks for 18 months. Subjects were divided into those with baseline T levels of <264 ng/dl (N = 43) and those with ≥264 ng/dl (N = 57). T and estradiol (E2) were measured by liquid chromatography/mass spectrometry; serum bone turnover markers (C-telopeptide [CTX], osteocalcin, and sclerostin), adiponectin, and leptin were measured by enzyme-linked immunosorbent assay; glycated hemoglobin (HbA1c) was measured by high-performance liquid chromatography; and areal BMD and body composition was measured by dual-energy x-ray absorptiometry (DXA).

RESULTS

Men with T < 264 ng/dl showed greater increases in total fat-free mass (FFM) at 18 months compared to those with T ≥ 264 ng/dl (4.2 ± 4.1 vs. 2.7 ± 3.8%; p = 0.047) and unadjusted appendicular FFM at 6 and 18 months (8.7 ± 11.5 vs. 4.4 ± 4.3%, 7.3 ± 11.6 vs. 2.4 ± 6.8%; p = 0.033 and p = 0.043, respectively). Men with T ≥ 264 ng/dl showed significant decreases in HbA1c at 12 months (-3.1 ± 9.2 vs. 3.2 ± 13.9%; p = 0.005), fasting glucose at 18 months (-4.2 ± 31.9 vs. 13.0 ± 57.3%; p = 0.040), LDL at 6 months (-6.4 ± 27.5 vs. 12.8 ± 44.1%; p = 0.034), and leptin at 18 months (-40.2 ± 35.1 vs. -27.6 ± 31.0%; p = 0.034) compared to those with T < 264 ng/dl. No significant differences in BMD and bone turnover markers were observed.

CONCLUSION

T therapy results in improvement in body composition irrespective of baseline T levels but T < 264 ng/dl is associated with greater improvement in FFM, whereas a T level of ≥264 ng/dl favors improvement in metabolic profile.

Obesity, Body Composition, and Sex Hormones: Implications for Cardiovascular Risk

Cardiovascular disease (CVD) continues to be the leading cause of death in adults, highlighting the need to develop novel strategies to mitigate cardiovascular risk. The advancing obesity epidemic is now threatening the gains in CVD risk reduction brought about by contemporary pharmaceutical and surgical interventions. There are sex differences in the development and outcomes of CVD; premenopausal women have significantly lower CVD risk than men of the same age, but women lose this advantage as they transition to menopause, an observation suggesting potential role of sex hormones in determining CVD risk. Clear differences in obesity and regional fat distribution among men and women also exist. While men have relatively high fat in the abdominal area, women tend to distribute a larger proportion of their fat in the lower body. Considering that regional body fat distribution is an important CVD risk factor, differences in how men and women store their body fat may partly contribute to sex-based alterations in CVD risk as well. This article presents findings related to the role of obesity and sex hormones in determining CVD risk. Evidence for the role of sex hormones in determining body composition in men and women is also presented. Lastly, the clinical potential for using sex hormones to alter body composition and reduce CVD risk is outlined. © 2022 American Physiological Society. Compr Physiol 12:1-45, 2022.

Glucose metabolic disorder in Klinefelter syndrome: a retrospective analysis in a single Chinese hospital and literature review

BACKGROUND

We aimed to investigate the clinical characteristics and islet β-cell function in patients with Klinefelter syndrome (KS) and hyperglycemia.

METHODS

This is a retrospective study. In total, 22 patients diagnosed with KS were identified from the electronic medical record system, including 9 patients with hyperglycemia (total patients with hyperglycemia, THG-KS group) and 5 hyperglycemic KS patients with oral glucose tolerance test (OGTT) results (HG-KS group). An additional 5 subjects with hyperglycemia and 5 normal glucose tolerance (NGT) subjects matched based on body mass index were included as the HG group and NGT group, respectively. Data from clinical and laboratory examinations were collected. We further performed a literature review of KS and hyperglycemia.

RESULTS

We found that KS patients developed abnormal glucose metabolism earlier in life than those without KS, and the median age was 17 years, ranging from 10 years to 19 years. Six of 17 (35.3%) patients were diagnosed with diabetes mellitus and 3 of 17 (17.6%) patients were diagnosed with prediabetes. Among 10 patients with both fasting blood glucose and insulin results recorded, there were 8 out of 17 (47.1%) KS patients had insulin resistance. The prevalence of hypertension and dyslipidemia was higher in patients with hyperglycemia and KS than in patients with NGT KS. Compared with the HG group, insulin sensitivity levels were lower in HG-KS group, whereas homeostasis model assessment of β-cell function levels (p = 0.047) were significantly, indicating higher insulin secretion levels in the HG-KS group.

CONCLUSIONS

KS patients develop hyperglycemia earlier in life than those without KS and show lower insulin sensitivity and higher insulin secretion. These patients also have a higher prevalence of other metabolic diseases and may have different frequencies of developing KS-related symptoms.

Nobiletin protects against diabetes-induced testicular injury via hypophysis-gonadal axis upregulation and amelioration of oxidative stress

BACKGROUND

Testicular injury is one of the most serious problems associated with diabetes mellitus. The present study aimed to compare the effects of two different doses of nobiletin and analyze its mechanisms of action against diabetes-induced testicular impairment in rats.

METHODS AND RESULTS

Streptozotocin injection was used to induce diabetes. Diabetic rats received nobiletin orally at 10 or 25 mg/kg daily for 30 days. Diabetic rats displayed significant elevations in glucose, glycosylated hemoglobin (HbA1c), Homeostatic Model of Insulin Resistance (HOMA-IR), and pro-inflammatory cytokines, while the serum levels of insulin, testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were significantly reduced. Histological changes to positivity for caspase-3 and decreased androgen receptors (AR) immunoexpression were observed in diabetic rats. Both doses of nobiletin improved hyperglycemia, reduced pro-inflammatory cytokines, and augmented insulin, testosterone, LH, and FSH levels. LH and FSH receptors and cytochrome P450 17 α-hydroxylase (CYP17A1) were markedly downregulated in terms of both gene and protein expression in testicular tissues of the diabetic group, effects that were markedly ameliorated with both doses of nobiletin. In addition, both doses significantly reduced lipid peroxidation and caspase-3 immunoexpression and improved the activity of the antioxidant enzymes and AR in testicular tissues of the diabetic group.

CONCLUSION

Both nobiletin doses showed protective effects against diabetes-induced testicular injury by reducing oxidative stress, hyperglycemia, inflammation, and caspase-3 and upregulating the hypophysis-gonadal axis and AR. The high dose of nobiletin was more effective than the lower one.

Effects of testosterone treatment on transgender males: A single-institution study

Objectives:

Data regarding gender-affirming hormone therapy in the Asian population are sparse. We aimed to evaluate the efficacy and safety of testosterone therapy in transgender men.

Methods:

A retrospective study chart review was conducted in a single university-based transgender clinic. Transgender men aged >18 years who newly started testosterone therapy during January 2015 to October 2019 were recruited. Physical changes, laboratory results, and adverse events, including cancer, thromboembolism, cardiovascular events, and death after masculinizing hormone therapy, were evaluated.

Results:

A total of 39 transgender men (mean age: 27.8 ± 6.0 years) were included. All individuals were treated with intramuscular testosterone injection with a mean follow-up of 25.2 ± 12.9 months. The most common maintenance regimen was testosterone enanthate 250 mg every 4 weeks. Masculinizing effects developed in all transgender men. There were no changes in body weight, and systolic and diastolic blood pressure. Hematocrit levels were 12% significantly increased from 39.9 ± 3.3% to 48.9 ± 2% (p < 0.001). Ten individuals (25.6%) had hematocrit >50%. Significant changes were found in decreased fasting plasma glucose, increased creatinine, and increased uric acid levels. A non-significantly increased alanine aminotransferase, increased low-density lipoprotein cholesterol, and decreased high-density lipoprotein cholesterol were observed. No thromboembolism, cancer, stroke, or coronary artery disease occurred.

Conclusions:

Gender-affirming hormone therapy is an effective and safe short-term treatment in Thai transgender men. Apart from the standard recommendation, uric acid, plasma glucose, and creatinine level evaluation before and during masculinizing hormone therapy are rational practices. An intramuscular testosterone enanthate 250 mg every 4 weeks is an alternative masculinizing regimen with decent efficacy and safety profile.

Overt hypogonadism is a cardiovascular risk factor in type 2 diabetic males: An observational study

We aimed to evaluate the effects of hypogonadism on metabolic and chronic complications in type 2 diabetic males. 261 nonobese males with type 2 diabetes aged 18-70 were involved in the study. Hypononadal males were divided into 2 groups as overt hypogonadism (total testosterone≤230 ng/dl) and borderline hypogonadism (230-345 ng/dl). The control group involved eugonadal diabetic males. Micro-macrovascular complications were recorded. 101 patients had hypogonadism (38.7%), and 160 patients were eugonadal (61.3%). Microvascular complication rate was not different, but macrovascular complication rate was significantly higher in hypogonadal males (42.6%/31.3%, p = 0.042). Optimal glycosylated haemoglobin (HbA1c) achievement(<7%) was significantly lower in hypogonadal patients (20.8%/31.3%, p = 0.043). Poor glycaemic control (HbA1c≥7%), presence of microvascular complication and increased triglyceride levels were independent risk factors for hypogonadism (OR: 1.5, p = 0.044;OR:3.89,p = 0.025 and OR: 1.0, p = 0.016 respectively). Overt hypogonadism, hypertension, hypercholesterolaemia and severe hypoglycaemia were independent risk factors for macrovascular complications (OR: 1.0, p = 0.027; OR:2.6, p = 0.002; OR: 1.8, p = 0.047 and OR: 1.0, p = 0.007 respectively), diabetes duration (≥5 years) and poor glycaemic control for microvascular complication (OR: 1.0, p = 0.031 and OR:2.0, p = 0.028). As a result, hypogonadism is frequent among diabetic males and poor glycaemic control may be an important contributing factor. Furthermore overt hypogonadism is an important cardiovascular risk marker. Therefore, ensuring eugonadism in diabetic patients may positively affect both glycaemic control and complications.

Testosterone treatment improves liver function and reduces cardiovascular risk: A long-term prospective study

Objectives: To report the association between testosterone treatment in hypogonadal men with hepatic steatosis, non-alcoholic fatty liver disease and cardiovascular disease (CVD). Methods: A prospective study was conducted to assess the physiological and functional performance of the long-term effects of testosterone undecanoate treatment on hepatic steatosis in 496 hypogonadal men. Two groups were studied, the treatment group (T-group) of 312 patients treated with TU 1000 mg every 12 weeks and followed for 8 years, and an untreated control group (C-group) of 184 patients. We evaluated liver functions and Fatty Liver Index (FLI) according to Mayo Clinic parameters and guidelines. Results: The T-group showed a decrease in the FLI (from a mean [SD] of 83.70 [12.15] to 67.12 [19.21]), bilirubin (from a mean [SD] of 1.69 [4.21] to 1.31 [1.91] mg/dL), triglycerides (from a mean [SD] of 254.87 [92.99] to 213.37 [66.91] mg/dL), and gamma-glutamyl-transferase (from a mean [SD] of 39.45 [11.51] to 29.11 [7.68] U/L) over the duration of the study. Other parameters were also reduced in the T-group such as body mass index (from a mean [SD] of 31.59 [4.51] to 29.50 [3.84] kg/m²) and waist circumference (from a mean [SD] of 107.51 [9.95] to 101.86 [9.28] cm). A total of 25 deaths (7.8%) were recorded in the T-group, among them, 11 (44%) were related to CVD. While in the C-group 28 deaths (15.2%) were recorded and all the reported deaths (100%) were related to CVD. Conclusions: The findings suggest that long-term testosterone therapy in hypogonadal men improves liver function. While, the physiological and functional improvements in the liver may be associated with a decrease in CVD-related mortality.

Abbreviations

ALT: alanine transaminase; AR: androgen receptor; AST: aspartate transaminase; BMI: body mass index; CVD: cardiovascular disease; FLI: Fatty Liver Index; γ-GT: gamma-glutamyl-transferase; MetS: metabolic syndrome; LDL: low-density lipoprotein; NAFLD: non-alcoholic fatty liver disease; RCT: randomised controlled trial; T2DM: type II diabetes mellitus; TT: total testosterone; TTh: testosterone therapy; TU: testosterone undecanoate; WC: waist circumference

Effect of Protein Intake on Visceral Abdominal Fat and Metabolic Biomarkers in Older Men With Functional Limitations: Results From a Randomized Clinical Trial

BACKGROUND

It remains controversial whether high protein diets improve cardiometabolic profile. We investigated whether increasing protein intake to 1.3 g/kg/day in functionally limited older adults with usual protein intake ≤RDA (0.8 g/kg/day) improves visceral fat accumulation and serum cardiovascular risk markers more than the recommended daily allowance (RDA).

METHODS

The Optimizing Protein Intake in Older Men Trial was a placebo-controlled, randomized trial in which 92 functionally limited men, ≥65 years, with usual protein intake ≤RDA were randomized for 6 months to: 0.8 g/kg/day protein plus placebo; 1.3 g/kg/day protein plus placebo; 0.8 g/kg/day protein plus testosterone enanthate 100 mg weekly; or 1.3 g/kg/day protein plus testosterone enanthate 100 mg weekly. In this substudy, metabolic and inflammatory serum markers were measured in 77 men, and visceral adipose tissue (VAT) was assessed using dual-energy x-ray absorptiometry in 56 men.

RESULTS

Treatment groups were similar in their baseline characteristics. Randomization to 1.3 g/kg/day protein group was associated with greater reduction in VAT compared to 0.8 g/kg/day group (between-group difference: -17.3 cm2, 95% confidence interval [CI]: -29.7 to -4.8 cm2, p = .008), regardless of whether they received testosterone or placebo. Changes in fasting glucose, fasting insulin, HOMA-IR, leptin, adiponectin, IL-6, and hs-CRP did not differ between the 0.8 versus 1.3 g/kg/day protein groups regardless of testosterone use.

CONCLUSIONS

Protein intake >RDA decreased VAT in functionally limited older men but did not improve cardiovascular disease risk markers.

CLINICAL TRIALS REGISTRATION NUMBER

NCT01275365.

Cardiovascular Disease, Hypogonadism and Erectile Dysfunction: Early Detection, Prevention and the Positive Effects of Long-Term Testosterone Treatment: Prospective Observational, Real-Life Data

Purpose

Erectile dysfunction (ED) is associated with testosterone deficiency and is a symptom of functional hypogonadism. A correlation between ED and cardiovascular disease (CVD) has been recognized, and ED has been proposed as an early marker of CVD. However, the relationship between ED and CVD risk in hypogonadism requires clarification and whether testosterone therapy (TTh) can be a beneficial treatment strategy, but long-term data are limited. This study investigates long-term TTh in men with hypogonadism and ED with a history of CVD.

Methods

Seventy-seven patients with a history of CVD and diagnosed with functional hypogonadism and erectile dysfunction (erectile function domain score <21 on the International Index of Erectile Function questionnaire (IIEF questions 1–5)) were enrolled and TTh effects on anthropometric and metabolic parameters investigated for a maximum duration of 12 years. All men received long-acting injections of testosterone undecanoate at 3-monthly intervals. Eight-year data were analysed. Data collection registry started in November 2004 till January 2015.

Results

In hypogonadal men receiving TTh, IIEF increased by 5.4 (p<0.001). Total weight loss was 23.6 ± 0.6 kg after 8 years. HbA1c had declined by an average of 2.0% (P<0.0001). Total cholesterol levels significantly declined following TTh after only 1 year (P<0.0001), and HDL increased from 1.6±0.5 at baseline to 2±0.5 mmol/L following 8 years of TTh (P<0.0001). SBP decreased from 164±14 at baseline to 133±9 mmHg, signifying a reduction of 33±1 mmHg (P<0.0001).

Conclusion

In hypogonadal men with a history of CVD, TTh improves and preserves erectile function over prolonged periods with concurrent sustained improvements in cardiometabolic risk factors. Measuring ED and testosterone status may serve as an important male health indicator predicting subsequent CVD-related events and mortality and TTh may be an effective add-on treatment in secondary prevention of cardiovascular events in hypogonadal men with a history of CVD.

Diabetes Status and Association With Risk of Tuberculosis Among Korean Adults

IMPORTANCE

The risk of tuberculosis (TB) associated with diabetes status, considering impaired fasting glucose or duration of diabetes, has not been well established.

OBJECTIVE

To evaluate the association of diabetes status with the development of TB in the general population.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used data from the Korean National Health Insurance System database. Adult participants without a history of TB who underwent a health screening in 2009 were included. Eligible participants were followed up for incident TB cases from 1 year after the day of health screening until December 31, 2018. Data analysis was performed from September 2019 to September 2020.

EXPOSURES

Five levels of diabetes status were evaluated: normal glucose, impaired fasting glucose (considered as without diabetes), new-onset diabetes, diabetes duration less than 5 years, and diabetes duration 5 years or longer (considered as having diabetes).

MAIN OUTCOMES AND MEASURES

Newly diagnosed TB.

RESULTS

Among 4 423 177 participants, the mean (SD) age was 46.5 (13.9) years, and there were 2 597 142 men (58.7%). A total of 26 458 participants (0.6%) received a diagnosis of TB within a median (interquartile range) of 8.3 (8.1-8.6) years of follow-up. An increased risk of TB was observed in participants with diabetes compared with those without diabetes (adjusted hazard ratio [aHR], 1.48; 95% CI, 1.42-1.53). Although participants with impaired fasting glucose did not show an increased risk of TB incidence (aHR, 0.97; 95% CI, 0.93-1.01), the risk of TB incidence increased with diabetes duration (new-onset diabetes, aHR, 1.32; 95% CI, 1.23-1.42; diabetes duration <5 years, aHR, 1.45; 95% CI, 1.36-1.54; diabetes duration ≥5 years, aHR, 1.57; 95% CI, 1.48-1.66). Among participants with new-onset diabetes, compared with those in the lowest decile (fasting plasma glucose [FPG] level ≥126 but <128 mg/dL), the risk of TB was significantly increased for those in the highest decile (FPG level ≥202 mg/dL, aHR, 1.79; 95% CI, 1.42-2.26).

CONCLUSIONS AND RELEVANCE

These findings suggest that longer diabetes duration is associated with development of TB, showing a dose-response association. Among participants with new-onset diabetes, incident TB was more common among those with FPG levels greater than or equal to 202 mg/dL.

Testosterone therapy and cardiovascular diseases

Since it was first synthesised in 1935, testosterone (T) has been viewed as the mythical Fountain of Youth, promising rejuvenation, restoring sexual appetites, growing stronger muscles, and quicker thinking. T is endowed with direct effects on myocardial and vascular structure and function, as well as on risk factors for cardiovascular (CV) disease. Indeed, low serum T levels are a risk factor for diabetes, metabolic syndrome, inflammation, and dyslipidaemia. Moreover, many studies have shown that T deficiency per se is an independent risk factor of CV and all-cause mortality. On this background and due to direct-to-patient marketing by drug companies, we have witnessed to the widespread use of T replacement therapy (TT) without clear indications particularly in late-life onset hypogonadism. The current review will dwell upon current evidence and controversies surrounding the role of T in the pathophysiology of CV diseases, the link between circulating T levels and CV risk, and the use of replacing T as a possible adjuvant treatment in specific CV disorders. Specifically, recent findings suggest that heart failure and type 2 diabetes mellitus represent two potential targets of T therapy once that a state of hypogonadism is diagnosed. However, only if ongoing studies solve the CV safety issue the T orchid may eventually 'bloom'.

Effects of Testosterone Replacement Therapy on Glycolipid Metabolism Among Hypogonadal Men withT2DM: A Meta-Analysis And System Review Of Randomized Controlled Trials

Introduction

Testosterone can improve glucose metabolism through multiple cellular mechanisms. However, it remains unclear as to whether hypogonadal men with type 2 diabetes mellitus (T2DM) can benefit from testosterone replacement therapy (TRT).

Aims

To assess the relative effect of TRT on glycolipid metabolism among hypogonadal men with T2DM.

Methods

: Electronic literature searches of the Cochrane Library, PubMed, MEDLINE, and EMBASE databases were conducted, up to the end of October 2020. Only studies that used randomized controlled trials (RCTs) were included in our systematic review. Main outcome measures From these studies, we extracted certain outcomes including changes in insulin resistance, glucose metabolism, and lipid parameters.

Results

There were a total of 8 studies that met our criteria. Four of these studies either did not have a consistent treatment strategy, or the control groups used untreated patients rather than patients that had been given a placebo. Thus, results from these four studies contributed to the variability in treatment outcomes. In four of the examined RCTs, there was no change in either the dose or the type of antidiabetic medication prescribed. Based on the homeostatic model assessment of insulin resistance, the pooled WMD was −0.34, 95% confidence interval (CI; −1.02, 0.34), P = .33; For fasting plasma glucose, the pooled WMD was −0.27, 95% CI (−1.02, 0.48), P = .48, the pooled WMD for HbA1c% was −0.00, 95% CI (−1.08, 1.08), P = 1.00.

Conclusions

Although certain RCTs showed that TRT improved insulin resistance and glycolipid metabolism when compared with the placebo or untreated control groups, these findings may partly be due to changes in antidiabetic therapy during the course of the study. In the current meta-analysis, analyses showed that TRT did not significantly improve insulin resistance or glycolipid metabolism. Future studies need to be rigorous in design and delivery, and comprehensive descriptions of all aspects of their methods should be included to further enable a more accurate appraisal and interpretation of the results.

Yu X, Wei Z, Liu Y, et al. Effects of Testosterone Replacement Therapy on Glycolipid Metabolism Among Hypogonadal Men with T2DM: A Meta-Analysis And System Review Of Randomized Controlled Trials. Sex Med 2021;9:100403.

Testosterone replacement therapy in men with type 2 diabetes mellitus and functional hypogonadism -an Integrated Diabetes and Endocrine Academy (IDEA) consensus guideline

BACKGROUND

Though testosterone replacement therapy in men with organic hypogonadism is established, its role in men with type 2 diabetes mellitus (T2DM) and functional hypogonadism is unclear.

METHODS

Thirteen experts addressed ten topic-specific questions after an in-depth review of literature, where all relevant issues were critically evaluated.

RESULTS

Ten recommendations concerning diagnosis and management of men with T2DM and functional hypogonadism have been put forward.

CONCLUSION

Routine measurement of serum testosterone in all, and inappropriate replacement of testosterone in asymptomatic T2DM men with functional hypogonadism and borderline low serum testosterone values, is not recommended.

The Role of testosterone treatment in patients with metabolic disorders

INTRODUCTION

The specific role of testosterone [T] replacement therapy [TRT] on glycometabolic profile and body composition, particularly in patients with metabolic syndrome [MetS] and/or type 2 diabetes mellitus [T2DM], is still the object of an intense debate.

AREAS COVERED

To discuss available evidence on the association between T and metabolic diseases and on the possible effect of T administration on metabolic disorder-associated hypogonadism. Both preclinical and clinical data have been considered. In addition, a meta-analysis of the available placebo and non-placebo-controlled randomized clinical trials [RCTs] investigating the effects of TRT in T2DM or MetS in several outcomes has been also performed.

EXPERT OPINION

Data derived from preclinical and clinical studies suggest that T administration, by reducing fat mass, can improve body composition and ameliorate some aspects of glucose metabolism. The effects of TRT on sexual function in patients with established metabolic derangements are inconsistent, whereas better results were observed in preclinical conditions or in patients with newly diagnosed T2DM.

Effect of Eurycoma longifolia standardised aqueous root extract-Physta® on testosterone levels and quality of life in ageing male subjects: a randomised, double-blind, placebo-controlled multicentre study

Background

Low testosterone levels cause physiological changes that compromise the quality of life in ageing men. A standardised water extract from the root of Eurycoma longifolia (EL), known as Physta^®, is known to increase testosterone levels.

Objective

To evaluate the safety and efficacy of Physta^® in improving the testosterone levels and quality of life in ageing male subjects.

Design

This randomised, double-blind, placebo-controlled study enrolled 105 male subjects aged 50-70 years with a testosterone level <300 ng/dL, BMI ≥ 18 and ≤30.0 kg/m². The subjects were given either Physta^® 100 mg, 200 mg or placebo daily for 12 weeks. The primary endpoints were changes in serum total and free testosterone levels. The secondary endpoints included changes in the level of sex hormone-binding globulin (SHBG), dihydroepiandrosterone (DHEA), glycated haemoglobin (HbA1c), insulin-like growth factor-1 (IGF-1), thyroid function tests (T3, T4, TSH and Free T3) and cortisol. Changes in Ageing Male Symptoms (AMS) score, Fatigue Severity Scale (FSS) score and muscle strength are other secondary endpoints. The safety of the intervention products was measured by complete blood count, lipid profile, liver and renal function tests.

Results

There was a significant increase in the total testosterone levels at week 12 (P < 0.05) in the Physta^® 100 mg group and at weeks 4 (P < 0.05), 8 (P < 0.01) and 12 (P < 0.001) in the Physta^® 200 mg group compared to placebo. No significant between-group differences in free testosterone levels were observed but a significant within-group increase occurred at weeks 4 (P < 0.01), 8 (P < 0.001) and 12 (P < 0.001) in the Physta^®100 mg group and at weeks 2 (P < 0.01), 4 (P < 0.01), 8 (P < 0.001) and 12 (P < 0.001) in the Physta^® 200 mg group. The AMS and FSS showed significant reduction (P < 0.001) in total scores at all time-points within- and between-group in both Physta^® groups. DHEA levels significantly increased (P < 0.05) within-group in both Physta^® groups from week 2 onwards. Cortisol levels significantly (P < 0.01) decreased in the Physta^® 200 mg group, while muscle strength significantly (P < 0.001) increased in both Physta^® groups at week 12 in the within-group comparison. There were no significant changes in SHBG. No safety related clinically relevant changes were observed.

Conclusion

Supplementation of Physta^® at 200 mg was able to increase the serum total testosterone, reduce fatigue and improve the quality of life in ageing men within 2 weeks' time.

Trial registration

This clinical study has been registered in ctri.nic.in (CTRI/2019/03/017959).

Association between T2DM and the lowering of testosterone levels among Kashmiri males

OBJECTIVE

The objective of this study is to study association between testosterone and diabetes in Kashmiri males.

METHODS

A total of 300 males with Type 2 diabetes visited an outpatient and inpatient clinic at Shri Maharaja Hari Singh (SMHS) hospital, Srinagar, J&K India. The blood sugar and HbA1c, which are the markers of diabetes, and sérum testosterone levels were measured. The blood samples from both the cases and controls were collected.

RESULTS

Out of 300 subjects, 42% had a testosterone deficiency. A relationship between type 2 diabetic males and healthy males was observed, and testosterone levels were determined to be significantly lower among diabetic males (p < 0.001) when compared to healthy males. Then, we compared diabetic markers among testosterone deficient and normal testosterone level groups; the mean fasting plasma glucose (p = 0.0019) and glycated haemoglobin (HbA1c; p = 0.0449) levels were significantly higher in the testosterone deficient group than in the control group. To elucidate the relationship between the serum total testosterone level and fasting plasma glucose and HbA1c values, Pearson's correlation test was performed. Fasting plasma glucose levels (r = -0.252, p = 0.001) and HbA1c values (r = -0.697, p = 0.001) showed a significant negative correlation with serum testosterone levels among diabetic males.

CONCLUSION

This study shows that diabetes causes low testosterone levels among males, and lower testosterone levels can act as a marker for diabetes. Thus, with timely intervention, mortality and co-morbidity associated with diabetes can be prevented.

Testosterone therapy for prevention and reversal of type 2 diabetes in men with low testosterone

Men with obesity and/or type 2 diabetes (T2D) have a high prevalence of testosterone deficiency (TD). Similarly, men with TD have an increased risk of developing obesity and/or T2D, and further body fat accumulation and deterioration of glycemic control create a vicious cycle. The landmark testosterone for diabetes mellitus trial, the largest randomized controlled trial of testosterone therapy (TTh) to date, confirms the beneficial effects of TTh on fat loss and gain in muscle mass, and that TTh for 2 years significantly reduces the risk of incident T2D, and may also reverse T2D. The testosterone for diabetes mellitus trial suggests that TTh reduces the risk of T2D and results in greater improvement in sexual function and wellbeing, beyond lifestyle intervention alone.

Comparison of metabolic effects of the progestational androgens dimethandrolone undecanoate and 11β-MNTDC in healthy men

BACKGROUND

Dimethandrolone (DMA) and 11β-methyl-19-nortestosterone (11β-MNT) are two novel compounds with both androgenic and progestational activity that are under investigation as potential male hormonal contraceptives. Their metabolic effects have never been compared in men.

OBJECTIVE

Assess for changes in insulin sensitivity and adiponectin and compare the metabolic effects of these two novel androgens.

MATERIALS/METHODS

In two clinical trials of DMA undecanoate (DMAU) and 11β-MNT dodecylcarbonate (11β-MNTDC), oral prodrugs of DMA and 11β-MNT, healthy men received drug, or placebo for 28 days. Insulin and adiponectin assays were performed on stored samples. Mixed model analyses were performed to compare the effects of the two drugs. Student's t test, or the non-parametric Kruskal-Wallis test as appropriate, was used to evaluate for an effect of active drug versus placebo.

RESULTS

Class effects were seen, with decrease in HDL-C and SHBG, and increase in weight and hematocrit, with no statistically significant differences between the two compounds. No changes in fasting glucose, fasting insulin, or HOMA-IR were seen with either compound. There was a slight decrease in adiponectin with DMAU that was not seen with 11β-MNTDC. An increase in LDL-C was seen with 11β-MNTDC but not with DMAU.

DISCUSSION

There were no significant changes in insulin resistance after 28 days of oral administration of these novel androgens despite a mild increase in weight. There may be subtle differences in their metabolic impacts that should be explored in future studies.

CONCLUSION

Changes in metabolic parameters should be carefully monitored when investigating androgenic compounds.

Inverse association between serum bilirubin level and testosterone deficiency in middle-aged and older men

Low serum bilirubin levels have been associated with increased risk of cardiovascular disease (CVD) and metabolic syndrome. Testosterone deficiency could also contribute to increased risk of CVD and metabolic syndrome. Therefore, this study aimed to examine the relationship between serum bilirubin level and testosterone deficiency in 1284 Korean men aged 45 to 70 years. Serum bilirubin level was categorized into quartiles: Q1 ≤ 0.7, Q2 0.8–0.9, Q3 1.0–1.1, and Q4 ≥ 1.2 mg/dL. Testosterone deficiency was defined as level less than 8.0 nmol/L, as suggested by the position statement of International Society of Andrology. The overall prevalence of testosterone deficiency was 5.8% and significantly decreased with the quartiles from Q1 to Q4. Compared with the referent fourth quartile (serum bilirubin ≥ 1.2 mg/dL), the ORs (95% CIs) for testosterone deficiency was 2.29 (1.04–4.94) for the first quartile after adjusting for age, fasting glucose, triglyceride, HDL-cholesterol, leukocyte count, hemoglobin, smoking status, and alcohol intake. We found inversely graded associations of serum bilirubin level with testosterone deficiency. These findings suggest that low bilirubin level may be interpreted as a state of testosterone deficiency in middle-aged and older men.