Physical activity counteracts metabolic syndrome-induced hypogonadotropic hypogonadism and erectile dysfunction in the rabbit

Pharmacological management of testosterone deficiency in men current advances and future directions

INTRODUCTION

Testosterone deficiency (TD) is relatively common in aging men, affecting around 2% of the general population. Testosterone replacement therapy (TRT) represents the most common medical approach for subjects who are not interested in fathering.

AREAS COVERED

This review summarizes advances in TRT, including approved or non-approved pharmacological options to overcome TD. When possible, a meta-analytic approach was applied to minimize subjective and biased interpretations of the available data.

EXPERT OPINION

During the last decade, several new TRT formulations have been introduced on the market, including oral, transdermal, and parenteral formulations. Possible advantages and limitations have been discussed appropriately. Anti-estrogens, including selective estrogen modulators or aromatase inhibitors still represent further possible off-label options. However, long-term side effects on sexual function and bone parameters constitute major limitations. Glucagon-like peptide 1 analogues can be an alternative option in particular for massive obesity-associated TD. Weight loss obtained through lifestyle modifications including diet and physical exercise should be encouraged in all overweight and obese patients. A combination of TRT and lifestyle changes can be considered in those subjects in whom a reversal of the condition cannot be expected in a reasonable time frame.

Investigating a novel surrogate indicator of adipose accumulation in relation to erectile dysfunction

INTRODUCTION

Although previous studies have linked obesity and erectile dysfunction, the novel surrogate indicators of adipose accumulation are more essential and dependable factors to consider. Therefore, the primary objective of the current investigation was to examine and clarify the association between metabolic score for visceral fat (METS-VF) and erectile dysfunction.

METHODS

Firstly, multivariate logistic regression analysis, smoothed curve fitting, and threshold effect analysis were employed to investigate the association between METS-VF and erectile dysfunction. Mediation analysis was also performed to evaluate the mediating role of homocysteine and inflammation. After that, subgroup analysis was carried out to examine the stability of the correlation of METS-VF with erectile dysfunction in various population settings. Furthermore, the area under the receiver operating characteristic (ROC) curve and eXtreme Gradient Boosting (XGBoost) algorithm were utilized to assess the capability of identifying METS-VF in comparison to the other four obesity-related indicators in identifying erectile dysfunction.

RESULTS

After adjusting for all confounding factors, METS-VF was strongly and favourablely correlated with erectile dysfunction. With each additional unit rise in METS-VF, the prevalence of erectile dysfunction increased by 141%. A J-shaped relationship between METS-VF and erectile dysfunction was discovered through smoothed curve fitting. Marital status, physical activity, and smoking status can potentially modify this association. This finding of the ROC curve suggests that METS-VF had a powerful identifying capacity for erectile dysfunction (AUC = 0.7351). Homocysteine and inflammation mediated 4.24% and 2.81%, respectively.

CONCLUSION

The findings of the current investigation suggest that METS-VF can be considered a dependable identifying indicator of erectile dysfunction.

The evolutionary conserved miR-137/325 tandem mediates obesity-induced hypogonadism and metabolic comorbidities by repressing hypothalamic kisspeptin

BACKGROUND

Obesity-induced hypogonadism (OIH) is a prevalent, but often neglected condition in men, which aggravates the metabolic complications of overweight. While hypothalamic suppression of Kiss1-encoded kisspeptin has been suggested to contribute to OIH, the molecular mechanisms for such repression in obesity, and the therapeutic implications thereof, remain unknown.

METHODS

A combination of bioinformatic, expression and functional analyses was implemented, assessing the role of the evolutionary-conserved miRNAs, miR-137 and miR-325, in mediating obesity-induced suppression of hypothalamic kisspeptin, as putative mechanism of central hypogonadism and metabolic comorbidities. The implications of such miR-137/325-kisspeptin interplay for therapeutic intervention in obesity were also explored using preclinical OIH models.

RESULTS

MiR-137/325 repressed human KISS1 3'-UTR in-vitro and inhibited hypothalamic kisspeptin content in male rats, while miR-137/325 expression was up-regulated, and Kiss1/kisspeptin decreased, in the medio-basal hypothalamus of obese rats. Selective over-expression of miR-137 in Kiss1 neurons reduced Kiss1/ kisspeptin and partially replicated reproductive and metabolic alterations of OIH in lean mice. Conversely, interference of the repressive actions of miR-137/325 selectively on Kiss1 3'-UTR in vivo, using target-site blockers (TSB), enhanced kisspeptin content and reversed central hypogonadism in obese rats, together with improvement of glucose intolerance, insulin resistance and cardiovascular and inflammatory markers, despite persistent exposure to obesogenic diet. Reversal of OIH by TSB miR-137/325 was more effective than chronic kisspeptin or testosterone treatments in obese rats.

CONCLUSIONS

Our data disclose that the miR-137/325-Kisspeptin repressive interaction is a major player in the pathogenesis of obesity-induced hypogonadism and a putative druggable target for improved management of this condition and its metabolic comorbidities in men suffering obesity.

SIGNIFICANCE STATEMENT

Up to half of the men suffering obesity display also central hypogonadism, an often neglected complication of overweight that can aggravate the clinical course of obesity and its complications. The mechanisms for such obesity-induced hypogonadism remain poorly defined. We show here that the evolutionary conserved miR137/miR325 tandem centrally mediates obesity-induced hypogonadism via repression of the reproductive-stimulatory signal, kisspeptin; this may represent an amenable druggable target for improved management of hypogonadism and other metabolic complications of obesity.

Advances in the treatment of functional male hypogonadism

INTRODUCTION

Functional hypogonadism is frequently found in obese men, particularly those with metabolic complications. Several possible therapeutic approaches could be considered.

AREAS COVERED

An extensive search on Medline, Embase, and Cochrane databases was performed to retrieve the available studies assessing the change of testosterone (T) and sexual function upon dieting or physical activity programs, as well as glucagon-like peptide 1 analogues. The role of lifestyle interventions associated with T replacement therapy (TRT) was also evaluated. The expert opinion provided here has been corroborated by meta-analyzing the results of the retrieved studies.

EXPERT OPINION

Current evidence supports the beneficial role of lifestyle modifications in increasing T and improving sexual function as a function of weight loss. While dieting programs are associated with greater effects in younger populations, physical exercise has major effects in older ones. Among the dieting programs, a very low-calorie ketogenic diet shows the best results; aerobic or endurance physical exercise perform similarly. The advantages of functional hypogonadism in lifestyle modifications are empowered by the association with TRT. Therefore, TRT may be a valuable complementary strategy to increase muscle mass and facilitate physical exercise while improving sexual symptoms, thus favoring the motivation and compliance for lifestyle interventions.

Dose-response association between 24-hour total movement activity and testosterone deficiency in adult males

Background and objectives

Previous studies on the relationship between physical activity and testosterone are limited and controversial. Hence we investigated whether high level of physical activity is associated with a low risk of testosterone deficiency (TD).

Methods

This cross-sectional analysis was conducted in a representative sample of US adult males who participated in the 2011-2014 cycle of the National Health and Nutrition Examination Survey (NHANES). We used the monitor independent movement summary (MIMS) to assess activity intensity, a novel physical activity metrics developed using raw data collected by accelerometers. Multivariable regression and smooth curve fitting was used to describe the relationships between physical activity and TD, and segmented regression model were used to analyze the threshold effect between them. Sensitivity analysis was conducted using interaction and stratified analysis.

Results

A U-shaped relationship between daily MIMS units and risk of TD was observed. The optimal value of daily MIMS units for the lowest risk of TD was 14.77 (×103), the risk of TD decreased by 5% in patients per unit increase of daily MIMS units when daily MIMS units <14.77 (×103) (adjusted OR = 0.95, 95%CI: 0.91, 0.99), but increased by 12% per unit increase of daily MIMS units when daily MIMS units ≥14.77 (×103) (adjusted OR = 1.12, 95%CI: 1.01, 1.23). In sensitivity analyses, the threshold effect was also similar according to baseline characteristics (P-interaction >0.05).

Conclusion

In a nationally representative sample of US adult males, light to moderate intensity physical activity is associated with a lower odds of TD, while high-intensity physical activity is associated with a higher risk of TD.

Does an increase in adipose tissue 'weight' affect male fertility? A systematic review and meta-analysis based on semen analysis performed using the WHO 2010 criteria

INTRODUCTION

Obesity negatively impact on the metabolism of sex hormones, leading to reduced testosterone serum levels. However, how the obesity could negatively impact on the overall gonadal function, particularly on male fertility, remained unclear so far.

OBJECTIVE

To systematically review evidences regarding the influence of body weight excess on the sperm production.

METHODS

A meta-analysis was conducted, searching all prospective and retrospective observational studies reporting male subjects older than 18 years old, with body weight excess from overweight to severe obesity were considered. Only studies using the V edition of the World Health Organization (WHO) manual for semen analysis interpretation were considered. No specific interventions were considered. Search was focused on studies comparing overweight/obese to normal weight subjects.

RESULTS

Twenty-eight studies were considered. Total sperm count and sperm progressive motility were significantly lower in overweight compared to normal weight subjects. Meta-regression analyses demonstrated that patients' age impacted on sperm parameters. Similarly, obese men showed lower sperm concentration, total sperm number, progressive and total motilities, and normal morphology lower than normal weight subjects. Reduced sperm concentration in obese men was influenced by age, smoking habit, varicocele, and total testosterone serum levels at meta-regression analyses.

CONCLUSIONS

The male potential fertility is reduced in subjects with increased body weight, compared to normal weight men. The higher was the increased body weight, the worst was the sperm quantity/quality. This result comprehensively included obesity among non-communicable risk factor for male infertility, shedding new lights on the negative impact of increased body weight on overall gonadal function.

Inhibition of integrin receptors reduces extracellular matrix levels, ameliorating benign prostate hyperplasia

Although a high prevalence of benign prostate hyperplasia (BPH) has been documented, the risk factors are poorly understood. Metabolic syndrome increases the risk of BPH. Succinylation, a type of posttranslational modification, mostly targets metabolic processes. The level of succinylation was investigated in 4 BPH patients and 4 healthy controls. Additionally, 176 patients with BPH were analyzed by using pan-antisuccinyllysine antibody blotting. TMT-labeling proteomic and sc-RNAseq Cellchat analyses were employed to identify key signaling factors involved in the development of BPH. In vivo and in vitro experiments were used to confirm the role of integrin receptors. The global succinylation level in BPH was higher than that in the healthy prostate. Positive correlations of prostate volume with IHC score sand urodynamics testing were found in large clinical cohorts. The extracellular matrix (ECM), metabolic processes and immune signaling were involved in succinylation in BPH, as indicated by using TMT-labeling proteomic analysis, and this finding was also confirmed by sc-RNAseq CellChat analysis. The proteins upregulated in SIRT5 knockout WPMY-1 cells were also enriched in the extracellular matrix and metabolic processes. More importantly, integrin receptor inhibition in a mouse model of BPH significantly ameliorated prostate hyperplasia. High levels of succinylation modifications were found in BPH, and succinylated proteins influenced the activation of the ECM. Inhibition of ECM signaling further ameliorated prostate hyperplasia in mice.

Metabolic syndrome and erectile dysfunction: a systematic review and meta-analysis study

PURPOSE

The clinical significance of metabolic syndrome (MetS) versus its single components in erectile dysfunction (ED) is conflicting. Thus, the purpose is to analyze the available evidence on the relationship between MetS-along with its components-and ED.

METHODS

All prospective and retrospective observational studies reporting information on ED and MetS were included. In addition, we here reanalyzed preclinical and clinical data obtained from a previously published animal model of MetS and from a consecutive series of more than 2697 men (mean age: 52.7 ± 12), respectively.

RESULTS

Data derived from this meta-analysis showed that MetS was associated with an up to fourfold increased risk of ED when either unadjusted or adjusted data were considered. Meta-regression analysis, performed using unadjusted statistics, showed that the MetS-related risk of ED was closely associated with all the MetS components. These associations were confirmed when unadjusted analyses from clinical models were considered. However, fully adjusted data showed that MetS-associated ED was more often due to morbidities included (or not) in the algorithm than to the MetS diagnostic category itself. MetS is also associated with low testosterone, but its contribution to MetS-associated ED-as derived from preclinical and clinical models-although independent, is marginal.

CONCLUSIONS

The results of our analysis suggest that MetS is a useless diagnostic category for studying ED. However, treating the individual MetS components is important, because they play a pivotal role in determining ED.

Relationship between weight-adjusted-waist index and erectile dysfunction in the United State: results from NHANES 2001-2004

Objective

The purpose of this study is to examine the association between a novel adiposity parameter, the weight-adjusted-waist index (WWI), and erectile dysfunction (ED).

Methods

According to National Health and Nutrition Examination Survey (NHANES) 2001-2004, a total of 3884 participants were categorized as ED and non-ED individuals. WWI was calculated as waist circumference (WC, cm) divided by the square root of weight (kg). Weighted univariable and multivariable logistic regression models were conducted to assess the correlation between WWI and ED. Smooth curve fitting was utilized to examine the linear association. The receiver operating characteristic (ROC) curve and DeLong et al.'s test were applied to compare the area under curve (AUC) value and predictive power among WWI, body mass index (BMI), and WC for ED.

Results

WWI was positively related to ED with the full adjustment [odds ratio (OR)=1.75, 95% confidence interval (95% CI): 1.32-2.32, p=0.002]. After converting WWI to a categorical variable by quartiles (Q1-Q4), compared to Q1 the highest WWI quartile was linked to an obviously increased likelihood of ED (OR=2.78, 95% CI: 1.39-5.59. p=0.010). Subgroup analysis revealed the stability of the independent positive relationship between WWI and ED. It was shown that WWI had a stronger prediction for ED (AUC=0.745) than BMI (AUC=0.528) and WC (AUC=0.609). Sensitivity analysis was performed to verify the significantly positive connection between WWI and stricter ED (OR=2.00, 95% CI: 1.36-2.94, p=0.003).

Conclusion

An elevated WWI was related to higher risks of ED in the United State adults, and a stronger predictive power of WWI for ED was observed than BMI and WC.

Pharmacotherapy of male hypogonadism

Hypogonadism is frequent with a prevalence of 2% in the general population. Hypogonadism may derive from any condition able to disrupt the hypothalamic-pituitary-testis (HPT) axis at one or more levels. Hypogonadism may be classified according to the age of onset, its potential reversibility and level of the HPT axis damage. The latter categorization is useful to decide on the treatment. Damages to the hypothalamus-pituitary may benefit from either GnRH, gonadotropin or T therapy with the former carrying the advantage of stimulating spermatogenesis. Conversely, when the testis is damaged, T therapy is the only option and restoration of spermatogenesis is not possible. Therefore, the choice of therapy is primarily based on the diagnosis and patients' needs and both should be carefully considered.

The role of testosterone in male sexual function

Sexual function, and testosterone (T) levels, progressively decline in aging men. Associated morbidities and metabolic disorders can accelerate the phenomenon. The specific contribution of low T to sexual function impairment in aging men has still not been completely clarified. Similarly, the role of T replacement therapy (TRT), as well as the combination of TRT with phosphodiesterase type 5 inhibitors (PDE5i) for patients with erectile dysfunction (ED), is still conflicting. Here we aim to summarize and critically discuss all available data supporting the contribution of low T to sexual impairment observed with aging as well as the possible role of TRT. Available data on men with sexual dysfunction show that reduced sexual desire is the most important correlate of male hypogonadism. Conversely, aging and associated morbidities substantially attenuate the relationship between ED and T. TRT is effective in improving sexual function in middle-aged and older subjects but its role is small and extremely variable. Lifestyle interventions can result in similar outcomes to those of TRT. In conclusion, it is our opinion that PDE5i along with lifestyle measures should be considered the first approach for treating ED even in subjects with milder T deficiency. When these interventions fail or are difficult to apply, TRT should be considered.

The metabolic role of prolactin: systematic review, meta-analysis and preclinical considerations

INTRODUCTION

Hyperprolactinemia has been proven to induce hypogonadism and metabolic derangements in both genders, while the consequences of prolactin (PRL) deficiency have been poorly investigated.

AREAS COVERED

To systematically review and analyze data from clinical studies focusing on the metabolic consequences of abnormally high prolactin levels (HPRL) and low prolactin levels (LPRL). In addition, data from preclinical studies about underlying pathophysiological mechanisms were summarized and discussed.

EXPERT OPINION

PRL contributes to providing the correct amount of energy to support the mother and the fetus/offspring during pregnancy and lactation, but it also has a homeostatic role. Pathological PRL elevation beyond these physiological conditions, but also its reduction, impairs metabolism and body composition in both genders, increasing the risk of diabetes and cardiovascular events. Hence, hypoprolactinemia should be avoided as much as possible during treatment with dopamine agonists for prolactinomas. Patients with hypoprolactinemia, because of endogenous or iatrogenic conditions, deserve, as those with hyperprolactinemia, careful metabolic assessment.

Androgens and male sexual function

Sexual symptoms are the most specific determinants of low testosterone (T) observed during adulthood. In this narrative review, we summarize the most important evidence supporting the positive relationships between endogenous T levels and sexual activity in the adult male, by using preclinical and clinical observations. In addition, we also report an update of our previous meta-analysis evaluating the effects of T treatment (TRT) on sexual functioning in subjects with T deficiency. Available data indicate that TRT of symptomatic hypogonadal men can improve several aspects of sexual life, including erection. However, the effect is rather modest and lower in subjects with associated metabolic conditions. The specific observed effects are similar to those derived from lifestyle intervention. Since TRT might result in body composition improvement, it is reasonable to suppose that an initial treatment with T can improve the willingness of hypogonadal subjects to perform physical exercise and to adhere to a healthier behavior. Similar data were derived from animal models. However, it should be important to recognize that lifestyle modifications should be the first step to promote weigh reduction. TRT can be combined with lifestyle interventions only in symptomatic hypogonadal subjects especially in the presence of comorbid metabolic conditions.

Pharmacological strategies for sexual recovery in men undergoing antipsychotic treatment

INTRODUCTION

: First- and second-generation antipsychotics are highly accountable for causing a plethora of medical side effects, ranging from metabolic imbalances to sexual dysfunction (SD), that frequently undermine patient-doctor relationships. Nevertheless, to date antipsychotics are one of the best treatment options for dealing with numerous either acute or chronic conditions like agitation, suicidality, depression, dementia, and of course psychosis. For these reasons, clinicians need to handle them wisely to preserve patients' sexual health, avoid poor therapeutic adherence and prevent high rates of therapy drop-out.

AREAS COVERED

: This article reviews the literature on pharmacologic approaches for management strategies in men who are administered with antipsychotics and developed SD. The etiology of antipsychotic-induced SD is also discussed.

EXPERT OPINION

: Clinicians must consider sexual life as a major health domain. To do so, a first step would be to measure and monitor sexual function by means of psychometric tools. Secondly, primary prevention should be conducted when choosing antipsychotics, i.e., picking sex-sparing compounds like aripiprazole or brexpiprazole. Thirdly, if sexolytic compounds cannot be dismissed, such as first-generation antipsychotics, risperidone, paliperidone, or amisulpride, then aripiprazole 5-20 mg/day adjunctive therapy has proven to be most effective in normalizing prolactin levels and consequently treating antipsychotic-induced SD.

The therapeutic effects of distinct exercise types on metabolic syndrome-induced reproductive system impairment in male rats: Potential contribution of mitochondria-related genes

A sedentary lifestyle and high fructose dietary habits cause diseases, such as metabolic syndrome (MS). The study was aimed to investigate the potential ameliorative effects of different exercise interventions on high fructose-induced MS-mediated reproductive system disruption of male rats. Rats were divided into four groups (n = 6): Control, MS, MS+aerobic exercise (AE) and MS+anaerobic exercise (ANE). MS was induced by using tap water containing 30% fructose for 8 weeks. After the induction of MS, AE/ANE implementations were started for 6 weeks. Testis tissue and serum samples of rats were stored for biochemical and molecular analyses. Serum total antioxidant status level increased in the MS+AE group compared to all groups. Also, serum total oxidant status level, which increased by MS, decreased with AE, but not altered with ANE. Moreover, MS markedly decreased serum luteinizing hormone, but not changed the follicle-stimulating hormone. However, serum hormone levels were similar to the control group in both MS+AE and MS+ANE groups. MS upregulated mitochondria-related genes' mRNA expressions (MFN2, PGC1A, PPARG, PARP2 and TXNL4B). These increases, except for PPARG, were normalized with both exercise types. These results revealed that mitochondria-related genes may have a crucial role in MS-mediated male reproductive impairment and therapeutic effects of exercises.

Comparison of characteristics between Chinese diabetes mellitus-induced erectile dysfunction populations and non-diabetes mellitus-induced erectile dysfunction populations: A cross-sectional study

BACKGROUND

Erectile dysfunction (ED) is a common disease in adult men, and diabetes is an independent risk factor for ED. However, there are few reports on the distinction between diabetes mellitus-induced erectile dysfunction (DMED) and non-DMED features, as well as ED features of varying severity in the two groups.

METHODS

A total of 365 ED patients treated at two clinics in China from 2019 to 2022 were included. Questionnaires of the International Index of Erectile Function (IIEF-5), Erectile Hardness Score (EHS), Premature Ejaculation Diagnostic Tool (PEDT), Patient Health Questionnaire-9 (PHQ-9), and Generalized Anxiety Disorder-7 (GAD-7) were administered to the patients. They were divided into three groups according to the IIEF-5 score: 5-7 for severe ED, 8-11 for moderate ED, and 12-21 for mild ED. In addition, the patient's age, weight, height, fasting blood glucose (FBG), total cholesterol (TC), triglycerides (TG), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), total testosterone (TT) and other indicators were also collected. Statistical analysis was performed using SPSS 26, comparing all parameters between groups.

RESULTS

Age (P<0.001), height (P=0.009), body mass index (BMI) (P=0.002), PEDT (P<0.001), FBG (P<0.001), FSH (P<0.001), TG (P<0.001), TT (P<0.001) and triglyceride-glucose index (TyG) (P<0.001) were significantly different between diabetic ED and nondiabetic ED subjects. The trend test in the nondiabetic ED population found a negative correlation between the IIEF-5 score and PHQ-9 (P for trend=0.15). Multivariate ordinal logistic regression in the diabetic ED population showed that elevated LH OR=11.37 (95% CI: 0.966, 3.897) and elevated PRL OR=4.10 (95% CI: 0.410, 2.411) were associated with an increased risk of more severe ED.

CONCLUSIONS

The aetiology, demographic parameters, degree of premature ejaculation, and related biochemical tests were significantly different between the DMED and non-DMED populations.

Metabolic syndrome and male fertility disorders: Is there a causal link?

Infertility is a global health problem affecting 10-15% of couples in reproductive age. Recent studies have provided growing evidence supporting that lifestyle factors can affect male fertility through alterations in endocrine profiles, spermatogenesis and/or sperm function. One of these critical factors could be the change in the food intake behavior in modern societies that produces metabolic alterations. Regarding this, metabolic syndrome (MetS) prevalence has increased in epidemic in the last 40-50 years. Although MetS is associated with advanced age, changes in lifestyles have accelerated the appearance of symptoms in the reproductive age. We review herein the current understanding of the relationship between MetS and the male reproductive status. For this purpose, in this narrative review a comprehensive literature search was made in both animal models and men, allowing us to evaluate such relationship. This analysis showed a high variability in the reproductive phenotypes observed in patients and mice suffering MetS, including sperm parameters, fertility and offspring health. In view of this, we proposed that the reproductive effects, which are diverse and not robust, observed among MetS-affected males, might depend on additional factors not associated with the metabolic condition and contributed not only by the affected male but also by his partner. With this perspective, this review provides a more accurate insight of this syndrome critical for the identification of specific diagnostic indicators and treatment of MetS-induced fertility disorders.

Pathological Significance of Macrophages in Erectile Dysfunction Including Peyronie's Disease

Erectile function is regulated by complex mechanisms centered on vascular- and nerve-related systems. Hence, dysregulation of these systems leads to erectile dysfunction (ED), which causes mental distress and decreases the quality of life of patients and their partners. At the molecular level, many factors, such as fibrosis, lipid metabolism abnormalities, the immune system, and stem cells, play crucial roles in the etiology and development of ED. Although phosphodiesterase type 5 (PDE5) inhibitors are currently the standard treatment agents for patients with ED, they are effective only in a subgroup of patients. Therefore, further insight into the pathological mechanism underlying ED is needed to discuss ED treatment strategies. In this review, we focused on the biological and pathological significance of macrophages in ED because the interaction of macrophages with ED-related mechanisms have not been well explored, despite their important roles in vasculogenic and neurogenic diseases. Furthermore, we examined the pathological significance of macrophages in Peyronie’s disease (PD), a cause of ED characterized by penile deformation (visible curvature) during erection and pain. Although microinjury and the subsequent abnormal healing process of the tunica albuginea are known to be important processes in this disease, the detailed etiology and pathophysiology of PD are not fully understood. This is the first review on the pathological role of macrophages in PD.

Cardiometabolic risk is unraveled by color Doppler ultrasound of the clitoral and uterine arteries in women consulting for sexual symptoms

Female sexual dysfunction (FSD) may be a mirror of a poor cardiometabolic state. In a small pilot study enrolling 71 women with FSD, we previously demonstrated that clitoral Pulsatility Index (PI) evaluated by using color Doppler ultrasound (CDU), reflecting vascular resistance, was associated with cardiometabolic risk factors. Data on uterine CDU in this context are lacking. First, to confirm previously reported data on the direct association between clitoral PI and cardiometabolic risk factors on a larger study population of women consulting for sexual symptoms; second, to investigate eventual similar correlations between cardiometabolic risk factors and CDU parameters of the uterine artery. We also ascertained whether uterine artery PI, similarly to what had previously been observed for clitoral artery PI, was directly related to body image uneasiness and psychopathological symptoms, assessed by validated questionnaires. N = 230 women consulting our clinic for sexual symptoms were examined with clitoral CDU and blood sampling and were asked to fill out the Female Sexual Function Index, the Middlesex Hospital Questionnaire (MHQ) and the Body Uneasiness Test (BUT). In a subgroup of women (n = 164), we also performed transvaginal CDU with measurement of uterine artery parameters. At multivariate analysis, we found a direct association between clitoral PI and body mass index (BMI) (p = 0.004), waist circumference (WC) (p = 0.004), triglycerides (p = 0.006), insulin (p = 0.029) and HOMA-IR (p = 0.009). Furthermore, a correlation between obesity and Metabolic Syndrome (MetS) and a higher clitoral PI was observed (p = 0.003 and p = 0.012, respectively). Clitoral PI was also correlated with MHQ-S (p = 0.010), a scale exploring somatized anxiety symptoms, and BUT-B Positive Symptom Distress Index (p = 0.010), a measure of body image concerns. Similarly, when investigating the uterine artery, we were able to demonstrate an association between its PI and BMI (p < 0.0001), WC (p = 0.001), insulin (p = 0.006), glycated haemoglobin (p =  < 0.0001), and HOMA-IR (p = 0.009). Women diagnosed with obesity and MetS showed significantly higher uterine PI values vs. those without obesity or MetS (p = 0.001 and p = 0.004, respectively). Finally, uterine PI was associated with BUT-A Global Severity Index (p < 0.0001) and with several other BUT-A subdomains. Vascular resistance of clitoral and uterine arteries is associated with cardiometabolic risk factors and body image concerns in women consulting for sexual symptoms. If further confirmed in different populations, our data could suggest CDU, a common examination method, as a useful tool for an identification—and possible correction—of cardiometabolic risk factors.

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.

Physical Activity and Female Sexual Dysfunction: A Lot Helps, But Not Too Much

BACKGROUND

Research on the relationship between physical activity (PA) and female sexual dysfunction (FSD) is lacking.

AIM

To investigate the clinical, psychological, and sexual correlates of PA in women with FSD.

METHODS

A non-selected series of n = 322 pre- and post-menopausal patients consulting for FSD was retrospectively studied. Regular involvement in PA and its frequency (<1 hour/week: sedentary, 1-3 hours/week: active, 4-6 hours/week: very active, >6 hours/week: extremely active) were investigated with a specific question.

OUTCOMES

FSDs, including HSDD (Hypoactive sexual desire disorder) and FGAD (Female genital arousal disorder), were diagnosed according to a structured and clinical interview. Participants underwent a physical examination and a clitoral Doppler ultrasound, and were asked to complete the Female Sexual Function Index, Female Sexual Distress Scale-Revised, Body Uneasiness Test, and Middlesex Hospital Questionnaire.

RESULTS

At multivariate analysis, women engaging in PA (67.4%, n = 217) scored significantly higher in several Female Sexual Function Index domains - including desire, arousal and lubrication - and showed lower sexual distress and lower resistance of clitoral arteries, as compared to sedentary women. A significant, inverse association between PA and HSDD was observed. Mediation analysis demonstrated that the negative association between PA and HSDD was partly mediated by body image concerns (Body Uneasiness Test Global severity index), psychopathological symptoms (Middlesex Hospital Questionnaire total score) and sexual distress (Female Sexual Distress Scale-Revised score). These latter 2 factors also partly mediated the association between PA and a reduced risk of FGAD, whilst a lower BMI was a full mediator in the relationship between PA and FGAD. Finally, extreme PA was associated with significantly worse scores in several psychosexual parameters (i,e, sexual satisfaction and histrionic/hysterical symptoms), even compared to a sedentary lifestyle.

CLINICAL IMPLICATIONS

Women consulting for FSD may gain benefits on desire, arousal, lubrication and sex-related distress from regular PA; however, physicians should remain alert to the downsides of excessive exercise.

STRENGTHS & LIMITATIONS

The main strength lies in the novelty of the findings. The main limitations are the cross-sectional nature, the clinical setting, the small sample size of the different PA groups, and the use of self-reported instruments for the evaluation of PA.

CONCLUSION

In women with FSD, PA was associated with better sexual function and clitoral vascularization, lower sexual distress and reduced odds of HSDD and FGAD; the benefits of PA on sexuality were mediated by both psychological and organic determinants; excessive PA was related with a poor overall sexual function and with a low sexual satisfaction. Maseroli E, Rastrelli G, Di Stasi V, et al. Physical Activity and Female Sexual Dysfunction: A Lot Helps, But Not Too Much. J Sex Med 2021;18:1217-1229.

Consequences of Anabolic-Androgenic Steroid Abuse in Males; Sexual and Reproductive Perspective

The real epidemiology and the possible consequences of anabolic-androgenic steroids (AAS) use still represent a very tricky task due to the difficulties in the quantification and detection of these drugs. Chronic use of AAS, frequently combined with other illicit substances, can induce tremendous negative effects on the reproductive system, but it is also associated with an increased overall and cardiovascular mortality risk. In the present review we summarize and discuss the available evidence regarding the negative impact of AAS on the male reproductive system, providing practical suggestions to manage these problems. For this purpose a meta-analysis evaluating the effects of AAS abusers vs. controls on several hormonal, reproductive and metabolic parameters was performed. In addition, in order to overcome possible limitations related to the combined use of different AAS preparations, we also retrospectively re-analyzed data on animal models treated with supraphysiological dosage of testosterone (T), performed in our laboratory. Available data clearly indicated that AAS negatively affect endogenous T production. In addition, increased T and estradiol circulating levels were also observed according to the type of preparations used. The latter leads to an impairment of sperm production and to the development of side effects such as acne, hair loss and gynecomastia. Furthermore, a worse metabolic profile, characterized by reduced high density lipoprotein and increased low density lipoprotein cholesterol levels along with an increased risk of hypertension has been also detected. Finally sexual dysfunctions, often observed upon doping, represent one the most probable unfavorable effects of AAS abuse.

Testosterone treatment is associated with reduced adipose tissue dysfunction and nonalcoholic fatty liver disease in obese hypogonadal men

PURPOSE

In both preclinical and clinical settings, testosterone treatment (TTh) of hypogonadism has shown beneficial effects on insulin sensitivity and visceral and liver fat accumulation. This prospective, observational study was aimed at assessing the change in markers of fat and liver functioning in obese men scheduled for bariatric surgery.

METHODS

Hypogonadal patients with consistent symptoms (n = 15) undergoing 27.63 ± 3.64 weeks of TTh were compared to untreated eugonadal (n = 17) or asymptomatic hypogonadal (n = 46) men. A cross-sectional analysis among the different groups was also performed, especially for data derived from liver and fat biopsies. Preadipocytes isolated from adipose tissue biopsies were used to evaluate insulin sensitivity, adipogenic potential and mitochondrial function. NAFLD was evaluated by triglyceride assay and by calculating NAFLD activity score in liver biopsies.

RESULTS

In TTh-hypogonadal men, histopathological NAFLD activity and steatosis scores, as well as liver triglyceride content were lower than in untreated-hypogonadal men and comparable to eugonadal ones. TTh was also associated with a favorable hepatic expression of lipid handling-related genes. In visceral adipose tissue and preadipocytes, TTh was associated with an increased expression of lipid catabolism and mitochondrial bio-functionality markers. Preadipocytes from TTh men also exhibited a healthier morpho-functional phenotype of mitochondria and higher insulin-sensitivity compared to untreated-hypogonadal ones.

CONCLUSIONS

The present data suggest that TTh in severely obese, hypogonadal individuals induces metabolically healthier preadipocytes, improving insulin sensitivity, mitochondrial functioning and lipid handling. A potentially protective role for testosterone on the progression of NAFLD, improving hepatic steatosis and reducing intrahepatic triglyceride content, was also envisaged.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02248467, September 25th 2014.

Metabolic Syndrome and Reproduction

Metabolic syndrome (MetS) and infertility are two afflictions with a high prevalence in the general population. MetS is a global health problem increasing worldwide, while infertility affects up to 12% of men. Despite the high prevalence of these conditions, the possible impact of MetS on male fertility has been investigated by a few authors only in the last decade. In addition, underlying mechanism(s) connecting the two conditions have been investigated in few preclinical studies. The aim of this review is to summarize and critically discuss available clinical and preclinical studies on the role of MetS (and its treatment) in male fertility. An extensive Medline search was performed identifying studies in the English language. While several studies support an association between MetS and hypogonadism, contrasting results have been reported on the relationship between MetS and semen parameters/male infertility, and the available studies considered heterogeneous MetS definitions and populations. So far, only two meta-analyses in clinical and preclinical studies, respectively, evaluated this topic, reporting a negative association between MetS and sperm parameters, testosterone and FSH levels, advocating, however, larger prospective investigations. In conclusion, a possible negative impact of MetS on male reproductive potential was reported; however, larger studies are needed.

Neuroprotective Effects of Testosterone in the Hypothalamus of an Animal Model of Metabolic Syndrome

Metabolic syndrome (MetS) is known to be associated to inflammation and alteration in the hypothalamus, a brain region implicated in the control of several physiological functions, including energy homeostasis and reproduction. Previous studies demonstrated the beneficial effects of testosterone treatment (TTh) in counteracting some MetS symptoms in both animal models and clinical studies. This study investigated the effect of TTh (30 mg/kg/week for 12 weeks) on the hypothalamus in a high-fat diet (HFD)-induced animal model of MetS, utilizing quantitative RT-PCR and immunohistochemical analyses. The animal model recapitulates the human MetS features, including low testosterone/gonadotropin plasma levels. TTh significantly improved MetS-induced hypertension, visceral adipose tissue accumulation, and glucose homeostasis derangements. Within hypothalamus, TTh significantly counteracted HFD-induced inflammation, as detected in terms of expression of inflammatory markers and microglial activation. Moreover, TTh remarkably reverted the HFD-associated alterations in the expression of important regulators of energy status and reproduction, such as the melanocortin and the GnRH-controlling network. Our results suggest that TTh may exert neuroprotective effects on the HFD-related hypothalamic alterations, with positive outcomes on the circuits implicated in the control of energy metabolism and reproductive tasks, thus supporting a possible role of TTh in the clinical management of MetS.

Leptin and inflammatory factors play a synergistic role in the regulation of reproduction in male mice through hypothalamic kisspeptin-mediated energy balance

BACKGROUND

Energy balance is closely related to reproductive function, wherein hypothalamic kisspeptin mediates regulation of the energy balance. However, the central mechanism of kisspeptin in the regulation of male reproductive function under different energy balance states is unclear. Here, high-fat diet (HFD) and exercise were used to change the energy balance to explore the role of leptin and inflammation in the regulation of kisspeptin and the hypothalamic-pituitary-testis (HPT) axis.

METHODS

Four-week-old male C57BL/6 J mice were randomly assigned to a normal control group (n = 16) or an HFD (n = 49) group. After 10 weeks of HFD feeding, obese mice were randomly divided into obesity control (n = 16), obesity moderate-load exercise (n = 16), or obesity high-load exercise (n = 17) groups. The obesity moderate-load exercise and obesity high-load exercise groups performed exercise (swimming) for 120 min/day and 120 min × 2 times/day (6 h interval), 5 days/week for 8 weeks, respectively.

RESULTS

Compared to the mice in the normal group, in obese mice, the mRNA and protein expression of the leptin receptor, kiss, interleukin-10 (IL-10), and gonadotropin-releasing hormone (GnRH) decreased in the hypothalamus; serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone levels and sperm quality decreased; and serum leptin, estradiol, and tumor necrosis factor-α (TNF-α) levels and sperm apoptosis increased. Moderate- and high-load exercise effectively reduced body fat and serum leptin levels but had the opposite effects on the hypothalamus and serum IL-10 and TNF-α levels. Moderate-load exercise had anti-inflammatory effects accompanied by increased mRNA and protein expression of kiss and GnRH in the hypothalamus and increased serum FSH, LH, and testosterone levels and improved sperm quality. High-load exercise also promoted inflammation, with no significant effect on the mRNA and protein expression of kiss and GnRH in the hypothalamus, serum sex hormone level, or sperm quality. Moderate-load exercise improved leptin resistance and inflammation and reduced the inhibition of kisspeptin and the HPT axis in obese mice. The inflammatory response induced by high-load exercise may counteract the positive effect of improving leptin resistance on kisspeptin and HPT.

CONCLUSION

During changes in energy balance, leptin and inflammation jointly regulate kisspeptin expression on the HPT axis.

The Inflammation Network in the Pathogenesis of Erectile Dysfunction: Attractive Potential Therapeutic Targets

BACKGROUND

Erectile dysfunction (ED) is an evolving health problem in the aging male population. Chronic low-grade inflammation is a critical component of ED pathogenesis and a probable intermediate stage of endothelial dysfunction, especially in metabolic diseases, with the inclusion of obesity, metabolic syndrome, and diabetes.

OBJECTIVE

This review will present an overview of preclinical and clinical data regarding common inflammatory mechanisms involved in the pathogenesis of ED associated with metabolic diseases and the effect of antiinflammatory drugs on ED.

METHODS

A literature search of existing pre-clinical and clinical studies was performed on databases [Pubmed (MEDLINE), Scopus, and Embase] from January 2000 to October 2019.

RESULTS

Low-grade inflammation is a possible pathological role in endothelial dysfunction as a consequence of ED and other related metabolic diseases. Increased inflammation and endothelial/prothrombotic markers can be associated with the presence and degree of ED. Pharmacological therapy and modification of lifestyle and risk factors may have a significant role in the recovery of erectile response through reduction of inflammatory marker levels.

CONCLUSION

Inflammation is the least common denominator in the pathology of ED and metabolic disorders. The inflammatory process of ED includes a shift in the complex interactions of cytokines, chemokines, and adhesion molecules. These data have established that anti-inflammatory agents could be used as a therapeutic opportunity in the prevention and treatment of ED. Further research on inflammation-related mechanisms underlying ED and the effect of therapeutic strategies aimed at reducing inflammation is required for a better understanding of the pathogenesis and successful management of ED.

Comparative Effectiveness of Electrical Stimulation and Aerobic Exercise in the Management of Erectile Dysfunction: A Randomized Clinical Trial

BACKGROUND

Electrical stimulation and aerobic exercise have been indicated to be beneficial in the management of erectile dysfunction individually. However, there is a scarcity of evidence comparing the two treatment approaches. This study investigated the effects of Electrical Stimulation (ES) compared with Eerobic Exercise (AE) in the management of individuals with Erectile Dysfunction (ED).

METHODS

This study was a single-blind parallel randomized clinical trial. Thirty (30) patients diagnosed with ED (Mean age of 39.17 ± 6.21 years) were recruited and randomized into two groups, A and B with 15 participants in each group. Group A received ES while Group B received AE. International Index of Erectile Function (IIEF-5) was used to assess the sexual functions of the participants at baseline and after 6 weeks of intervention. Within-group and between-group differences were analyzed using dependent and independent t-tests respectively.

RESULTS

The result indicated a significant difference between groups A and B [20.83 (1.83) Vs 14.33 (2.07), p=0.001] after 6 weeks of intervention. However, the mean effect was significantly higher in the ES group than in the AE group.

CONCLUSION

The finding of this study indicated that ES is more effective than AE in the management of individuals with ED.Trial Registration: Pan African Clinical Trial Registry (PACTR201906776769795).

Exercise and caloric restriction improve cardiovascular and erectile function in rats with metabolic syndrome

The aim of this study is to examine the possible benefits of exercise and caloric restriction (CR) on cardiovascular hemodynamics, erectile function, and antioxidant system in metabolic syndrome (MS). Sixty male Spraque-Dawley rats were divided into five groups; control, MS, MS + CR, MS + exercise (EXC), and MS + CR + EXC. To induce MS, 10% fructose solution was applied for 3 months. Thereafter, in CR groups calorie was restricted 40% and in EXC groups swimming was performed for 6 weeks. Body weight, blood glucose, and blood pressure (BP) levels were measured before and after MS induction and at the end of the experiment. After decapitation, tumor necrosis factor (TNF)-α, adiponectin (ADP), and plasminogen activator inhibitor (PAI)-1 levels were investigated in blood, oxidative stress parameters were examined in heart, aorta, and corpus cavernosum (CC) tissues. Isometric contraction in isolated tissue bath was studied in aorta and CC tissues. Animals subjected to exercise and CR had decreased BP and blood glucose levels. Impaired contraction-relaxation responses in MS group were improved with exercise and CR. MS-induced increase in TNF-α, PAI-1, malondialdehyde (MDA), and decrease in ADP, glutathione (GSH), and superoxide dismutase (SOD) were normalized with exercise and CR. Exercise and CR may be beneficial against changes in cardiovascular hemodynamics caused by MS.

Lifestyle, metabolic disorders and male hypogonadism - A one-way ticket?

Hypogonadism is more frequent among men with common metabolic diseases, notably obesity and type 2 diabetes. Indeed, endocrine disruption caused by metabolic diseases can trigger the onset of hypogonadism, although the underlying molecular mechanisms are not entirely understood. Metabolic diseases are closely related to unhealthy lifestyle choices, such as dietary habits and sedentarism. Therefore, hypogonadism is part of a pathological triad gathering unhealthy lifestyle, metabolic disease and genetic background. Additionally, hypogonadism harbors the potential to aggravate underlying metabolic disorders, further sustaining the mechanisms leading to disease. To what extent does lifestyle intervention in men suffering from these metabolic disorders can prevent, improve or reverse hypogonadism, is still controversial. Moreover, recent evidence suggests that the metabolic status of the father is related to the risk of inter and transgenerational inheritance of hypogonadism. In this review, we will address the proposed mechanisms of disease, as well as currently available interventions for hypogonadism.

Cardiovascular Risks of Androgen Deprivation Therapy for Prostate Cancer

Androgen deprivation therapy (ADT) is the gold standard treatment in patients with locally advanced or metastatic prostate cancer (PC). Emerging evidence has documented a tight association between ADT and body composition, along with metabolic profile impairment. These alterations might underpin the observed ADT-related increase in cardiovascular (CV) and thromboembolic (venous thromboembolism, VTE) mortality and morbidity. However, the specific mechanisms underlying these associations have not yet been completely elucidated. In the present review we summarize and discussed the available evidence linking ADT to increased cardio-metabolic risk, using both preclinical and clinical data. When possible, meta-analytic studies were preferred. Preclinical evidence, using a rabbit model of gonadotrophin-releasing hormone analogue-induced hypogonadism, indicates that the induced condition is associated with a dramatic increase in visceral adiposity and with an impairment of acetylcholine induced vascular relaxation, along with an increased propensity towards fatty liver. This suggests a direct role of ADT in inducing a worsened metabolic profile. In contrast, available clinical data are not sufficient to clarify a direct pathogeniclink between reduced testosterone (T) and altered metabolism. In fact, although T deprivation is associated with an altered metabolism, it is possible that the association between ADT and CV or VTE risk could simply be the result of a selection bias, related to the poor health status of patients with advanced PC. Despite the aforementioned considerations, all patients who are candidatesfor ADT should be screened for CV risk factors at baseline and monitored during the therapy. Life-style modifications and physical exercise are strongly encouraged.

The KiSS-1/GPR54 system: Essential roles in physiological homeostasis and cancer biology

KiSS-1, first identified as an anti-metastasis gene in melanoma, encodes C-terminally amidated peptide products, including kisspeptin-145, kisspeptin-54, kisspeptin-14, kisspeptin-13 and kisspeptin-10. These products are endogenous ligands coupled to G protein-coupled receptor 54 (GPR54)/hOT7T175/AXOR12. To date, the regulatory activities of the KiSS-1/GPR54 system, such as puberty initiation, antitumor metastasis, fertility in adulthood, hypothalamic-pituitary-gonadal axis (HPG axis) feedback, and trophoblast invasion, have been investigated intensively. Accumulating evidence has demonstrated that KiSS-1 played a key role in reproduction and served as a promising biomarker relative to the diagnosis, identification of therapeutic targets and prognosis in various carcinomas, while few studies have systematically summarized its subjective factors and concluded the functions of KiSS-1/GPR54 signaling in physiology homeostasis and cancer biology. In this review, we retrospectively summarized the regulators of the KiSS-1/GPR54 system in different animal models and reviewed its functions according to physiological homeostasis regulations and above all, cancer biology, which provided us with a profound understanding of applying the KiSS-1/GPR54 system into medical applications.

Male and female sexual dysfunction in diabetic subjects: Focus on new antihyperglycemic drugs

The association between diabetes mellitus (and its micro- and macro-vascular complications) and erectile dysfunction is widely known and the presence of hypogonadism may further complicate sexual dysfunction and quality of life, given the association between hypogonadism and reduced libido, ejaculatory disorders, and depressive symptoms. However, the recent introduction of novel antidiabetic agents with a wide range of mechanism of action may have a significant impact both on male and female sexuality directly (by inducing side effects as urinary tract infections) and indirectly (improving metabolic status and reducing diabetes complications behind sexual dysfunctions). To date only few papers are reporting the sexual effects of these treatments and, often, these are not comparable in their results. Conversely, female sexual dysfunctions are somehow under-investigated. Data on prevalence is heterogeneous and specific pathogenic mechanisms, as well as the burden of psychological factors, are still heatedly debated. The aim of this narrative review is to summarize current knowledge and stressing out the need to diagnose male and female sexual dysfunctions also in light of the impact of treatments with novel antidiabetic agents. This would highlight the still unmet needs for sexual care in a diabetes care setting and could represent an incentive for future discussions, as well as a required theoretical starting point for studies on this subject.

Metabolically healthy and unhealthy obesity in erectile dysfunction and male infertility

Introduction: Metabolically unhealthy obesity (MUHO) is the most important preventable cardiovascular (CV) risk factor. Recently, the significance of metabolically healthy obesity (MHO) as a CV risk factor has raised increasing interest. MUHO is a known risk factor for erectile dysfunction (ED); however, the effect of MHO on ED has barely been investigated. This review aims at summarizing the evidence supporting the relation of MUHO and MHO to male sexual functioning and fertility. Areas covered: An extensive Medline search on obesity and ED or male infertility was conducted to summarize the role of MUHO or MHO on male sexual dysfunction and infertility. Expert opinion: Longitudinal studies have demonstrated that MHO causes vascular damage, which is consistent with the impairment in penile blood flows found in ED subjects. In this population, MHO is a predictor of CV events. The relationship between male infertility and MUHO is currently debated and data on MHO are almost completely lacking. The only available study did not find an association between obesity classes and semen parameters. Although the andrological correlates of MHO must be better assessed, in the current state, evidence suggests that MHO does not represent a benign condition and measures for improving lifestyle are mandatory.

Treatment of Functional Hypogonadism Besides Pharmacological Substitution

A dichotomic distinction between “organic” and “functional” hypogonadism is emerging. The former is an irreversible condition due to congenital or “acquired” “organic” damage of the brain centers or of the testis. Conversely, the latter is a potentially reversible form, characterized by borderline low testosterone (T) levels mainly secondary to age-related comorbidities and metabolic derangements, including metabolic syndrome (MetS). Life-style modifications, - here reviewed and, when possible, meta-analyzed -, have documented that weight-loss and physical exercise are able to improve obesity-associated functional hypogonadism and its related sexual symptoms. A rabbit experimental model, of MetS originally obtained in our lab, showed that endurance training (PhyEx) completely reverted MetS-induced hypogonadotropic hypogonadism by reducing hypothalamus inflammation and testis fibrosis eventually allowing for a better corpora cavernosa relaxation and response to sildenafil. Physicians should strongly adapt all the reasonable strategies to remove/mitigate the known conditions underlying functional hypogonadism, including MetS and obesity. Physical limitations, including reduced muscle mass and increased fat mass, along with low self-confidence, also due to the sexual problems, might limit a subject's propensity to increase physical activity and dieting. A short term T treatment trial, by improving muscle mass and sexual function, might help hypogonadal obese patients to overcome the overfed, inactive state and to become physically and psychologically ready for changing their lifestyle.

Male Obesity-related Secondary Hypogonadism - Pathophysiology, Clinical Implications and Management

The single most significant risk factor for testosterone deficiency in men is obesity. The pathophysiological mechanisms involved in male obesity-related secondary hypogonadism are highly complex. Obesity-induced increase in levels of leptin, insulin, proinflammatory cytokines and oestrogen can cause a functional hypogonadotrophic hypogonadism with the defect present at the level of the hypothalamic gonadotrophin-releasing hormone (GnRH) neurons. The resulting hypogonadism by itself can worsen obesity, creating a self-perpetuating cycle. Obesity-induced hypogonadism is reversible with substantial weight loss. Lifestyle-measures form the cornerstone of management as they can potentially improve androgen deficiency symptoms irrespective of their effect on testosterone levels. In selected patients, bariatric surgery can reverse the obesity-induced hypogonadism. If these measures fail to relieve symptoms and to normalise testosterone levels, in appropriately selected men, testosterone replacement therapy could be started. Aromatase inhibitors and selective oestrogen receptor modulators are not recommended due to lack of consistent clinical trial-based evidence.