Metabolic syndrome induces inflammation and impairs gonadotropin-releasing hormone neurons in the preoptic area of the hypothalamus in rabbits

The galectin-3 inhibitor selvigaltin reduces liver inflammation and fibrosis in a high fat diet rabbit model of metabolic-associated steatohepatitis

Introduction

Galectin-3 is a pro-fibrotic β-galactoside binding lectin highly expressed in fibrotic liver and implicated in hepatic fibrosis. Selvigaltin (previously known as GB1211) is a novel orally active galectin-3 small molecule inhibitor that has high affinity for galectin-3 (human KD = 25 nM; rabbit KD = 12 nM) and high oral bioavailability in rabbits and man. In this study the efficacy of selvigaltin was investigated in a high fat diet (HFD) rabbit model of metabolic-associated steatohepatitis (MASH).

Methods

Male New Zealand White rabbits were individually caged under standard conditions in a temperature and humidity-controlled room on a 12 h light/darkness cycle. After 1 week of regular diet (RD), rabbits were randomly assigned for 8 or 12 weeks to different groups: RD/vehicle, RD/selvigaltin, HFD (8 weeks), HFD/vehicle and HFD/selvigaltin (0.3, 1.0, 5.0 or 30 mg/kg selvigaltin with vehicle/selvigaltin p.o. dosed therapeutically q.d. 5 days per week from week 9 or 12). Liver inflammation, steatosis, ballooning, and fibrosis was measured via blood metabolic markers, histomorphological evaluation [Oil Red O, Giemsa, Masson's trichome, picrosirius red (PSR) and second harmonic generation (SHG)], and mRNA and protein expression.

Results

Steatosis, inflammation, ballooning, and fibrosis were all increased from RD to HFD/vehicle groups. Selvigaltin demonstrated target engagement by significantly decreasing galectin-3 levels in the liver as measured via immunohistochemistry and mRNA analysis. Selvigaltin dose-dependently reduced biomarkers of liver function (AST, ALT, bilirubin), inflammation (cells foci), and fibrosis (PSR, SHG), as well as decreasing the mRNA and protein expression of several key inflammation and fibrosis biomarkers (e.g., IL6, TGFβ3, SNAI2, collagen). Doses of 1.0 or 5.0 mg/kg demonstrated consistent efficacy across most biological endpoints supporting the current clinical doses of selvigaltin being investigated in liver disease.

Discussion

Selvigaltin significantly reduced hepatic inflammation and fibrosis in an HFD rabbit model of MASH following therapeutic dosing for 4 weeks in a dose-dependent manner. These data support the human selvigaltin dose of 100 mg b.i.d. that has been shown to reduce key liver biomarkers during a clinical study in liver cirrhosis.

Association between life's essential 8 and testosterone deficiency in US men: findings from national health and nutrition examination survey (NHANES) 2011-2016

Background

Testosterone deficiency (TD) is closely associated with cardiovascular diseases (CVD). We intended to explore the association of Life's Essential 8 (LE8), the recently updated measurement of cardiovascular health, with the prevalence of TD among US male adults.

Methods

The population-based cross-sectional study selected male adults aged 20 years or older from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2016. According to the American Heart Association definitions, the LE8 score was measured on a scale of 0-100, and divided into health behavior and health factor scores, simultaneously. Furthermore, these scores were categorized into low (0-49), moderate (50-79), and high (80-100) classifications. TD is defined as a total testosterone level below 300ng/dL. Correlations were investigated by weighted multivariable logistic regression, and the robustness of the results were verified by subgroup analysis.

Results

A total of 4971 male adults with an average age of 47.46 ± 0.41 years were eligible for the final analyses, of whom 1372 were determined to have TD. The weighted mean LE8 score of the study population was 68.11 ± 0.41. After fully adjusting potential confounders, higher LE8 scores were significantly associated with low risk of TD (odd ratio [OR] for each 10-point increase, 0.79; 95% CI, 0.71-0.88) in a linear dose-response relationship. Similar patterns were also identified in the association of health factor scores with TD (OR for each 10-point increase, 0.74; 95% CI, 0.66-0.83). These results persisted when LE8 and health factor scores was categorized into low, moderate, and high groups. The inversed association of LE8 classifications and TD remained statistically significant among older, obese, and men without CVD.

Conclusions

LE8 and its health factor subscales scores were negatively associated with the presence of TD in linear fashions. Promoting adherence to optimal cardiovascular health levels may be advantageous to alleviate the burden of TD.

Impact of metabolic syndrome factors on sperm DNA fragmentation in males from infertile couples: A systematic review and meta-analysis

PURPOSE

To investigate the impact of metabolic syndrome factors on sperm DNA fragmentation (sDF) in males from infertile couples.

METHODS

A systematic literature search was performed across ten databases for literature published from January 1, 2013 until September 13, 2023. The protocol has been registered on PROSPERO (CRD42023458359), and the literature search strategy is adhered to the PRISMA framework. Studies that evaluated sDF, as indicated by DNA fragmentation index (%DFI), in males from infertile couples in relation to metabolic syndrome factors were included. Meta-analysis, using random effects model and Bayesian framework network, was performed, and data were presented as Standardized Mean Differences (SMD) with corresponding 95 % Confidence Interval (CI).

RESULTS

Of the 2579 citations identified, eleven studies were included in this meta-analysis. The findings revealed that the %DFI was not associated with overall metabolic syndrome factors (p-tot = 0.235; SMD = 0.57 [95 %CI: -0.37, 1.52]), metabolic syndrome status (p-tot = 0.337; SMD = 0.08 [95 %CI: -0.08, 0.24), increased body mass index (p-tot = 0.237; SMD = 0.71 [95 %CI: -0.47, 1.89]), or glycaemic profile (p-tot = 0.93; SMD = 0.13 [95 %CI: -2.72, 2.98]). High levels of heterogeneity were observed (p < 0.01) in all subgroups, except for metabolic syndrome status.

CONCLUSION

The association between metabolic syndrome factors and sDF is conflicting. However, interpreting the association requires caution, as confounding factors, indicated by high heterogeneity, may conceal the outcome. Metabolic syndrome may influence other factors contributing to male infertility, highlighting the importance of promoting a healthy lifestyle.

Obesity-Related Hypogonadism in Women

Obesity-related hypogonadotropic hypogonadism is a well-characterized condition in men (termed male obesity-related secondary hypogonadism; MOSH); however, an equivalent condition has not been as clearly described in women. The prevalence of polycystic ovary syndrome (PCOS) is known to increase with obesity, but PCOS is more typically characterized by increased gonadotropin-releasing hormone (GnRH) (and by proxy luteinizing hormone; LH) pulsatility, rather than by the reduced gonadotropin levels observed in MOSH. Notably, LH levels and LH pulse amplitude are reduced with obesity, both in women with and without PCOS, suggesting that an obesity-related secondary hypogonadism may also exist in women akin to MOSH in men. Herein, we examine the evidence for the existence of a putative non-PCOS "female obesity-related secondary hypogonadism" (FOSH). We précis possible underlying mechanisms for the occurrence of hypogonadism in this context and consider how such mechanisms differ from MOSH in men, and from PCOS in women without obesity. In this review, we consider relevant etiological factors that are altered in obesity and that could impact on GnRH pulsatility to ascertain whether they could contribute to obesity-related secondary hypogonadism including: anti-Müllerian hormone, androgen, insulin, fatty acid, adiponectin, and leptin. More precise phenotyping of hypogonadism in women with obesity could provide further validation for non-PCOS FOSH and preface the ability to define/investigate such a condition.

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.

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.

Beyond the Metabolic Syndrome: Non-Obvious Complications of Obesity in Children

Obesity is currently one of the most significant public health challenges worldwide due to the continuous increase in obesity rates among children, especially younger children. Complications related to obesity, including serious ones, are increasingly being diagnosed in younger children. A search was performed from January 2023 to September 2023 using the PubMed, Cochrane Library, Science Direct, MEDLINE, and EBSCO databases. The focus was on English-language meta-analyses, systematic reviews, randomized clinical trials, and observational studies worldwide. Four main topics were defined as follows: disorders of glucose metabolism; liver disease associated with childhood obesity; the relationship between respiratory disorders and obesity in children; and the effects of obesity on the hypothalamic-pituitary-gonadal axis and puberty. Understanding potential complications and their underlying mechanisms can expedite the diagnostic process and enhance the effectiveness of treatment. We aspire that this study will bring insight into the often-overlooked complications associated with obesity.

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.

The Association Between Lipid Serum and Semen Parameters: a Systematic Review

Increased lipid levels sometimes not only affect sexual function but also are considered to harm semen quality. It is often a suspicion that elevated lipids are a factor in infertility. We conduct a systematic review. Articles that met the criteria were identified according to The Preferred Reporting Items for Systematic Review and Meta-analysis of recommendations in the PubMed, ProQuest, EBSCO, Web of Science Wiley Online, Springer Link, Scopus, and Science Direct databases with no time restriction for publication. Seven studies are eligible for qualitative analysis from nine studies that have the potential to be assessed. These studies measure the correlation of serum lipids (VLDL, HDL, LDL, triglycerides, total cholesterol, free cholesterol, phospholipids, free fatty acids) with semen parameters (concentration, motility, morphology, DNA fragmentation index). Although not all studies consistently report that lipids impact semen quality, this review suspects that lipids have a significant impact on sperm quality. This study implies that it is necessary to maintain lipid levels to maintain sperm quality and quality of life. However, further investigation with an observational cohort study design needs to be carried out to assess the effect of lipids on semen quality more precisely for the promotion of reproductive health care.

Testosterone therapy in diabetes and pre-diabetes

BACKGROUND

Type 2 diabetes mellitus and pre-diabetes are associated with reduced circulating testosterone levels. However, the role of testosterone replacement therapy in these patients is still conflicting.

OBJECTIVES

To summarize and critically analyze available data on the possible effect of testosterone administration in men with glucose abnormalities.

MATERIALS AND METHODS

A comprehensive systematic review was performed. When available, meta-analytic data were preferred. To better analyze the relationship between testosterone and the pre-diabetes condition, a systematic analysis was performed and the data obtained with the latter search were used for a meta-analytic approach. Finally, clinical data derived from a consecutive series of 4682 patients seeking medical care for sexual dysfunction at the University of Florence were also considered.

RESULTS

Patients with impaired fasting glucose were characterized by a 3 nmol/L lower level of total testosterone when compared to controls. Similarly, impaired fasting glucose was associated with a 1.8-fold increased risk of hypogonadism, when compared to subjects with normal glucose levels. Waist circumference and body mass index resulted as being the best predictors of reduced total testosterone levels. Secondary hypogonadism was two times higher in subjects with impaired fasting glucose when compared to rates observed in the general population. Testosterone replacement therapy was able to improve body composition, insulin resistance, and glucose profile both in impaired fasting glucose and type 2 diabetes mellitus whereas its role on body weight, lipid profile, and sexual function was less evident.

DISCUSSION AND CONCLUSION

Weight loss and physical activities are able to improve both metabolic profile and testosterone levels. The combined approach of testosterone replacement therapy and lifestyle modifications could be suggested in symptomatic hypogonadal men to better motivate patients to perform physical activity which can eventually result in weight loss as well as metabolic profile and sexual function improvement. Whether or not these approaches can prevent the development of type 2 diabetes mellitus from pre-clinical conditions requires more studies.

Effects of benzo[a]pyrene on the reproductive axis: Impairment of kisspeptin signaling in human gonadotropin-releasing hormone primary neurons

The neuroendocrine control of reproduction is strictly coordinated at the central level by the pulsatile release of gonadotropin-releasing hormone (GnRH) by the hypothalamic GnRH neurons. Alterations of the GnRH-network, especially during development, lead to long-term reproductive and systemic consequences, also causing infertility. Recent evidence shows that benzo[a]pyrene (BaP), a diffuse pollutant that can play a role as an endocrine disruptor, affects gonadal function and gamete maturation, whereas data demonstrating its impact at hypothalamic level are very scarce. This study investigated the effects of BaP (10 μM) in a primary cell culture isolated from the human fetal hypothalamus (hfHypo) and exhibiting a clear GnRH neuron phenotype. BaP significantly decreased gene and protein expression of both GnRH and kisspeptin receptor (KISS1R), the master regulator of GnRH neuron function. Moreover, BaP exposure increased phospho-ERK1/2 signaling, a well-known mechanism associated with KISS1R activation. Interestingly, BaP altered the electrophysiological membrane properties leading to a significant depolarizing effect and it also significantly increased GnRH release, with both effects being not affected by kisspeptin addition. In conclusion, our findings demonstrate that BaP may alter GnRH neuron phenotype and function, mainly interfering with KISS1R signaling and GnRH secretion and therefore with crucial mechanisms implicated in the central neuroendocrine control of reproduction.

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.

Identification of the hub genes related to adipose tissue metabolism of bovine

Due to the demand for high-quality animal protein, there has been consistent interest in how to obtain more high-quality beef. As well-known, the adipose content of beef has a close connection with the taste and quality of beef, and cattle with different energy or protein diet have corresponding effects on the lipid metabolism of beef. Thus, we performed weighted gene co-expression network analysis (WGCNA) with subcutaneous adipose genes from Norwegian red heifers fed different diets to identify hub genes regulating bovine lipid metabolism. For this purpose, the RNA sequencing data of subcutaneous adipose tissue of 12-month-old Norwegian red heifers (n = 48) with different energy or protein levels were selected from the GEO database, and 7,630 genes with the largest variation were selected for WGCNA analysis. Then, three modules were selected as hub genes candidate modules according to the correlation between modules and phenotypes, including pink, magenta and grey60 modules. GO and KEGG enrichment analysis showed that genes were related to metabolism, and participated in Rap, MAPK, AMPK, VEGF signaling pathways, and so forth. Combined gene interaction network analysis using Cytoscape software, eight hub genes of lipid metabolism were identified, including TIA1, LOC516108, SNAPC4, CPSF2, ZNF574, CLASRP, MED15 and U2AF2. Further, the expression levels of hub genes in the cattle tissue were also measured to verify the results, and we found hub genes in higher expression in muscle and adipose tissue in adult cattle. In summary, we predicted the key genes of lipid metabolism in the subcutaneous adipose tissue that were affected by the intake of various energy diets to find the hub genes that coordinate lipid metabolism, which provide a theoretical basis for regulating beef quality.

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.

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.

The Interaction of Obesity and Reproductive Function in Adolescents

Obesity is increasing worldwide, including in pediatrics. Adequate nutrition is required for initiation of menses, and there is a clear secular trend toward earlier pubertal onset and menarche in females in countries around the globe. Similar findings of earlier pubertal start are suggested in males. However, as individuals and populations have crossed into over-nutritional states including overweight and obesity, the effect of excess weight on disrupting reproductive function has become apparent. Hypothalamic hypogonadism and polycystic ovary syndrome are two conditions where reproductive function appears to directly relate to excess weight. Clinical findings in individuals with certain polygenic and monogenic obesity syndromes, which also have reproductive disruptions, have helped elucidate neurologic pathways that are common to both. Clinical endocrinopathies such as hypothyroidism or panhypopituitarism also aide in the understanding of the role of the endocrine system in weight gain. Understanding the intersection of obesity and reproductive function may lead to future therapies which can treat both conditions.

The relation between obesity, kisspeptin, leptin, and male fertility

Over the past decades, obesity and infertility in men increased in parallel, and the association between both phenomena have been examined by several researchers. despite the fact that there is no agreement, obesity appears to affect the reproductive potential of men through various mechanisms, such as changes in the hypothalamic-pituitary-testicular (HPT) axis, spermatogenesis, sperm quality and/or alteration of sexual health. Leptin is a hormone produced by the adipose tissue, and its production elevates with increasing body fat. Many studies have supported the relationship between raised leptin production and reproductive function regulation. In fact, Leptin acts on the HPT axis in men at all levels. However, most obese men are insensitive to increased production of endogenous leptin and functional leptin resistance development. Recently, it has been recommended that Kisspeptin neurons mediate the leptin's effects on the reproductive system. Kisspeptin binding to its receptor on gonadotropin-releasing hormone (GnRH) neurons, activates the mammal's reproductive axis and stimulates GnRH release. Increasing infertility associated with obesity is probably mediated by the Kisspeptin-GnRH pathway. In this review, the link between obesity, kisspeptin, leptin, and male fertility will be discussed.

Mechanisms Driving Palmitate-Mediated Neuronal Dysregulation in the Hypothalamus

The hypothalamus maintains whole-body homeostasis by integrating information from circulating hormones, nutrients and signaling molecules. Distinct neuronal subpopulations that express and secrete unique neuropeptides execute the individual functions of the hypothalamus, including, but not limited to, the regulation of energy homeostasis, reproduction and circadian rhythms. Alterations at the hypothalamic level can lead to a myriad of diseases, such as type 2 diabetes mellitus, obesity, and infertility. The excessive consumption of saturated fatty acids can induce neuroinflammation, endoplasmic reticulum stress, and resistance to peripheral signals, ultimately leading to hyperphagia, obesity, impaired reproductive function and disturbed circadian rhythms. This review focuses on the how the changes in the underlying molecular mechanisms caused by palmitate exposure, the most commonly consumed saturated fatty acid, and the potential involvement of microRNAs, a class of non-coding RNA molecules that regulate gene expression post-transcriptionally, can result in detrimental alterations in protein expression and content. Studying the involvement of microRNAs in hypothalamic function holds immense potential, as these molecular markers are quickly proving to be valuable tools in the diagnosis and treatment of metabolic disease.

Treatment potential of LPCN 1144 on liver health and metabolic regulation in a non-genomic, high fat diet induced NASH rabbit model

PURPOSE

Low free testosterone (T) level in men is independently associated with presence and severity of Non-Alcoholic Steatohepatitis (NASH). The histological and molecular effects of oral testosterone prodrug LPCN 1144 treatment on hepatic fibrosis and NASH features are unknown. A metabolic syndrome-induced NASH model in rabbits consuming high fat diet (HFD) has been previously used to assess treatment effects of injectable T on hepatic fibrosis and NASH features. Here we present results on LPCN 1144 in this HFD-induced, NASH preclinical model.

METHODS

Male rabbits were randomly assigned to five groups: regular diet (RD), HFD, HFD + 1144 vehicle (HFD + Veh), HFD + 1144 (1144), and HFD + 1144 + α-tocopherol (1144 + ALPHA). Rabbits were sacrificed after 12 weeks for liver histological, biochemical and genetic analyses. Histological scores were obtained through Giemsa (inflammation), Masson's trichrome (steatosis and ballooning), and Picrosirius Red (fibrosis) staining.

RESULTS

Compared to RD, HFD and HFD + Veh significantly worsened NASH features and hepatic fibrosis. Considering HFD and HFD + Veh arms, histological and biomarker features were not significantly different. Both 1144 and 1144 + ALPHA arms improved mean histological scores of NASH as compared to HFD arm. Importantly, percentage of fibrosis was improved in both 1144 (p < 0.05) and 1144 + ALPHA (p = 0.05) treatment arms vs. HFD. Both treatment arms also reduced HFD-induced inflammation and fibrosis mRNA markers. Furthermore, 1144 treatments significantly improved HFD-induced metabolic dysfunctions.

CONCLUSIONS

Histological and biomarker analyses demonstrate that LPCN 1144 improved HFD-induced hepatic fibrosis and NASH biochemical, biomolecular and histochemical features. These preclinical findings support a therapeutic potential of LPCN 1144 in the treatment of NASH and of hepatic fibrosis.

Comparison of Medical Management versus Bariatric Surgery for Obesity Management: Effects on Sexual Function

Both bariatric surgery and medical modification approaches to weight loss for individuals with obesity have been evaluated for their impacts on sexual health, however, a comparison between these interventions has not been undertaken. A convenience sample of 52 females were recruited from community medical and surgical weight loss clinics to participate; 25 received medical management that consisted of dietary guidance and exercise training, and 27 received bariatric surgery. Participants completed self-report questionnaires before and after treatment that examined sexual functioning, sexual satisfaction, relationship satisfaction, depression, anxiety, and body esteem. Sexual functioning decreased in both groups regardless of weight loss approach, p = .037. Sexual satisfaction increased for both groups, p = .005, with significantly greater improvements seen in the medical management group, p = .038. Measures of sexual desire, arousal, and pain did not change after treatment, and there were no group or time effects on relationship satisfaction, depressive symptoms, or body esteem. Lubrication and orgasm function decreased over time for both groups. These results highlight that sexual satisfaction can improve with either weight loss approach, even when sexual function decreases.

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.

Skeletal endocrinology: where evolutionary advantage meets disease

The regulation of whole-body homeostasis by the skeleton is mediated by its capacity to secrete endocrine signaling molecules. Although bone-derived hormones confer several adaptive benefits, their physiological functions also involve trade-offs, thus eventually contributing to disease. In this manuscript, we discuss the origins and functions of two of the best-studied skeletal mediators, fibroblast growth factor 23 and osteocalcin, in an evolutionary context. Moreover, we provide a theoretical framework seeking to explain the broad involvement of these two hormones in amniote physiology as well as their potential to fuel the development and progression of diseases. Vice versa, we outline which perturbations might be amenable to manipulation of these systems and discuss limitations and ongoing challenges in skeletal endocrine research. Finally, we summarize unresolved questions and potential future studies in this thriving field.

Late-onset hypogonadism: Clinical evidence, biological aspects and evolutionary considerations

The growing life expectancy in modern societies has raised scientific interest in identifying medical interventions to alleviate age-associated pathologies such as vascular calcification, cognitive decline, sarcopenia, osteoporosis and sexual dysfunction. Although no such single treatment has thus far been established in humans, some clinicians and patients have set their hopes on testosterone replacement therapy (TRT) as a potential "fountain of youth" for aging men. While TRT has proven effective in ameliorating distinct symptoms of late-onset hypogonadism (LOH), its safety remains to be demonstrated. Besides humans, multiple other species exhibit age-related reductions in circulating testosterone levels, raising the question whether such changes are an inherent, pathological feature of growing organismal age or rather reflect an adaptive response. In this manuscript, we apply key principles of evolutionary medicine to testosterone biology and LOH to provide a novel perspective on these two fields. Additionally, we discuss insightful data derived from the animal kingdom to illustrate the plasticity of individual testosterone trajectories across the lifespan, outline cost-benefit-considerations of TRT in LOH and highlight potential caveats of such therapies.

Mapping of Microglial Brain Region, Sex and Age Heterogeneity in Obesity

The prevalence of obesity has increased rapidly in recent years and has put a huge burden on healthcare worldwide. Obesity is associated with an increased risk for many comorbidities, such as cardiovascular diseases, type 2 diabetes and hypertension. The hypothalamus is a key brain region involved in the regulation of food intake and energy expenditure. Research on experimental animals has shown neuronal loss, as well as microglial activation in the hypothalamus, due to dietary-induced obesity. Microglia, the resident immune cells in the brain, are responsible for maintaining the brain homeostasis and, thus, providing an optimal environment for neuronal function. Interestingly, in obesity, microglial cells not only get activated in the hypothalamus but in other brain regions as well. Obesity is also highly associated with changes in hippocampal function, which could ultimately result in cognitive decline and dementia. Moreover, changes have also been reported in the striatum and cortex. Microglial heterogeneity is still poorly understood, not only in the context of brain region but, also, age and sex. This review will provide an overview of the currently available data on the phenotypic differences of microglial innate immunity in obesity, dependent on brain region, sex and age.

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.

Anti-neuroinflammatory effect of daidzein in human hypothalamic GnRH neurons in an in vitro membrane-based model

Phytoestrogens can control high-fat diet-induced hypothalamic inflammation that is associated with severe consequences, including obesity, type 2 diabetes, cardiovascular and neurodegenerative diseases. However, the phytoestrogen anti-neuroinflammatory action is poorly understood. In this study, we explored the neuroprotection mediated by daidzein in hypothalamic neurons by using a membrane-based model of obesity-related neuroinflammation. To test the daidzein therapeutic potential a biohybrid membrane system, consisting of hfHypo GnRH-neurons in culture on PLGA membranes, was set up. It served as reliable in vitro tool capable to recapitulate the in vivo structure and function of GnRH hypothalamic tissue. Our findings highlighted the neuroprotective role of daidzein, being able to counteract the palmitate induced neuroinflammation. Daidzein protected hfHypo GnRH cells by downregulating cell death, proinflammatory processes, oxidative stress, and apoptosis. It also restored the proper cell morphology and functionality through a mechanism which probably involves the activation of ERβ and GPR30 receptors along with the expression of GnRH peptide and KISS1R.

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.

Effect of Inflammation on Female Gonadotropin-Releasing Hormone (GnRH) Neurons: Mechanisms and Consequences

: Inflammation has a well-known suppressive effect on fertility. The function of gonadotropin-releasing hormone (GnRH) neurons, the central regulator of fertility is substantially altered during inflammation in females. In our review we discuss the latest results on how the function of GnRH neurons is modified by inflammation in females. We first address the various effects of inflammation on GnRH neurons and their functional consequences. Second, we survey the possible mechanisms underlying the inflammation-induced actions on GnRH neurons. The role of several factors will be discerned in transmitting inflammatory signals to the GnRH neurons: cytokines, kisspeptin, RFamide-related peptides, estradiol and the anti-inflammatory cholinergic pathway. Since aging and obesity are both characterized by reproductive decline our review also focuses on the mechanisms and pathophysiological consequences of the impact of inflammation on GnRH neurons in aging and obesity.

The Role of Diet and Weight Loss in Improving Secondary Hypogonadism in Men with Obesity with or without Type 2 Diabetes Mellitus

Despite growing recognition of the issue, obesity represents one of the most common public health problems, and its rates are still increasing globally. Among the number of comorbidities and complications associated with obesity, hypogonadism is listed, and this disorder, although frequently neglected, is characterized by a relevant impact on both quality of life and life expectancy. It is generally accepted that hypogonadism secondary to obesity is functional since it is reversible following weight loss. This review summarizes all current research examining the bidirectional relationship between excess body weight and low testosterone levels. Specifically, it evaluates the role that diet, with or without physical activity, plays in improving body weight and hypogonadism in adult and elderly men with obesity, with or without type 2 diabetes mellitus.

Testosterone and Cardiovascular Risk: Meta-Analysis of Interventional Studies

BACKGROUND

The relationship between testosterone (T) and cardiovascular (CV) risk in men is conflicting.

AIM

To verify whether T therapy (TTh) represents a possible risk factor for CV morbidity and mortality.

METHODS

We conducted a random effect meta-analysis considering all available data from pharmaco-epidemiological studies as well as randomized placebo-controlled trials (RCTs).

OUTCOMES

CV mortality and morbidity were investigated.

RESULTS

After screening, 15 pharmaco-epidemiological and 93 RCT studies were considered. The analysis of pharmaco-epidemiological studies documented that TTh reduces overall mortality and CV morbidity. Conversely, in RCTs, TTh had no clear effect, either beneficial or detrimental, on the incidence of CV events. However, a protective role of TTh on CV morbidity was observed when studies enrolling obese (body mass index >30 kg/m²) patients were scrutinized (Mantel-Haenszel odds ratio 0.51 [95% CI 0.27-0.96]; P = .04), although this association disappeared when only high-quality RCTs were considered (Mantel-Haenszel odds ratio 0.64 [95% CI 0.22-1.88]; P = .42). Finally, an increased risk of CV diseases was observed in RCTs when T preparations were prescribed at dosages above those normally recommended, or when frail men were considered.

CLINICAL IMPLICATIONS

Pharmaco-epidemiological studies showed that TTh might reduce CV risk, but this effect was not confirmed when RCTs were considered.

STRENGTHS & LIMITATIONS

Meta-analysis of pharmaco-epidemiological studies indicates that TTh reduces overall mortality and CV morbidity. In addition, even in RCTs, a protective role of TTh on CV morbidity was envisaged when studies enrolling obese (body mass index >30 kg/m²) patients were considered. Pharmaco-epidemiological studies should be considered with caution due to the lack of completeness of follow-up and of the management of missing data. In addition, properly powered placebo-controlled RCTs with a primary CV end point, in men with late-onset hypo-gonadism, are not yet available. Finally, the duration of all studies evaluated in the present meta-analysis is relatively short, reaching a maximum of 3 years.

CONCLUSIONS

Data from RCTs suggest that treatment with T is not effective in reducing CV risk, however, when TTh is correctly applied, it is not associated with an increase in CV risk and it may have a beneficial effect in some sub-populations. Corona G, Rastrelli G, Di Pasquale G, et al. Testosterone and Cardiovascular Risk: Meta-Analysis of Interventional Studies. J Sex Med 2018;15:820-838.

Identifying roles for peptidergic signaling in mice

Despite accumulating evidence demonstrating the essential roles played by neuropeptides, it has proven challenging to use this information to develop therapeutic strategies. Peptidergic signaling can involve juxtacrine, paracrine, endocrine, and neuronal signaling, making it difficult to define physiologically important pathways. One of the final steps in the biosynthesis of many neuropeptides requires a single enzyme, peptidylglycine α-amidating monooxygenase (PAM), and lack of amidation renders most of these peptides biologically inert. PAM, an ancient integral membrane enzyme that traverses the biosynthetic and endocytic pathways, also affects cytoskeletal organization and gene expression. While mice, zebrafish, and flies lacking Pam (Pam^KO/KO ) are not viable, we reasoned that cell type-specific elimination of Pam expression would generate mice that could be screened for physiologically important and tissue-specific deficits. Conditional Pam^cKO/cKO mice, with loxP sites flanking the 2 exons deleted in the global Pam^KO/KO mouse, were indistinguishable from wild-type mice. Eliminating Pam expression in excitatory forebrain neurons reduced anxiety-like behavior, increased locomotor responsiveness to cocaine, and improved thermoregulation in the cold. A number of amidated peptides play essential roles in each of these behaviors. Although atrial natriuretic peptide (ANP) is not amidated, Pam expression in the atrium exceeds levels in any other tissue. Eliminating Pam expression in cardiomyocytes increased anxiety-like behavior and improved thermoregulation. Atrial and serum levels of ANP fell sharply in PAM myosin heavy chain 6 conditional knockout mice, and RNA sequencing analysis identified changes in gene expression in pathways related to cardiac function. Use of this screening platform should facilitate the development of therapeutic approaches targeted to peptidergic pathways.

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.

Increasing hypothalamic nucleobindin 2 levels and decreasing hypothalamic inflammation in obese male mice via diet and exercise alleviate obesity-associated hypogonadism

To explore the role of nesfatin-1 in regulating male reproductive function during energy balance variation, we employed an obese mouse model which was first induced by a high-fat diet (HFD) and followed by interventions of a normal diet (ND) and/or moderate exercise, and then serum reproductive hormones of male mice, hypothalamic nucleobindin 2 (NUCB2)/nesfatin-1, inflammatory factors, and gonadotropin-releasing hormone (GnRH) levels were tested. Our findings showed that both serum nesfatin-1, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T) levels and hypothalamic NUCB2/nesfatin-1 and Gnrh mRNA levels were reduced, whereas, the mRNA and protein levels of hypothalamic tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, inhibitor kappa B kinase β (IKKβ), and nuclear factor (NF)-κB were increased in obese male mice. Diet, exercise, and diet combined with exercise interventions reversed the decreases in serum nesfatin-1, FSH, LH, and T levels; increased hypothalamic NUCB2/nesfatin-1 and Gnrh mRNA levels; and reduced hypothalamic TNF-α, IL-1β, IKKβ, and NF-κB levels. These changes were accompanied by reduced adiposity, and these effects were more obvious in the diet combined with exercise group. Overall, our findings suggested that the hypogonadotropic hypogonadism associated with obesity may be induced by reduced hypothalamic NUCB2/nesfatin-1 levels, which attenuated the stimulatory effect on GnRH directly or indirectly by suppressing its anti-inflammatory effect in the brain. Diet and/or exercise interventions were able to alleviate the hypogonadotropic hypogonadism associated with obesity, potentially by increasing hypothalamic NUCB2/nesfatin-1 levels.

Investigating the basis of sexual dysfunction during late-onset hypogonadism

Late-onset hypogonadism (LOH) is the term used to describe the decline in serum testosterone levels associated with increasing age in men above 40 years. A number of symptoms are attributed to LOH, but the most common association is that of sexual dysfunction. LOH has recently come under greater scrutiny with the widespread use of testosterone therapy, and concerns regarding the efficacy and safety of testosterone replacement therapy have been raised. In particular, the cardiovascular safety and the beneficial effects of testosterone replacement therapy on general health have been questioned. This review will give an overview of the current evidence for the relationship of LOH and male sexual dysfunction.

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

Metabolic syndrome (MetS) clusters cardiovascular and metabolic risk factors along with hypogonadism and erectile dysfunction. Lifestyle modifications including physical exercise (PhyEx) are well-known treatments for this condition. In this study, we analyzed the effect of PhyEx on hypothalamic-pituitary-testis axis and erectile function by use of an animal MetS model, previously established in rabbits fed a high-fat diet (HFD). Rabbits fed a regular diet (RD) were used as controls. A subset of both groups was trained on a treadmill. HFD rabbits showed typical MetS features, including HG (reduced T and LH) and impairment of erectile function. PhyEx in HFD rabbits completely restored plasma T and LH and the penile alterations. At testicular and hypothalamic levels, an HFD-induced inflammatory status was accompanied by reduced T synthesis and gonadotropin-releasing hormone (GnRH) immunopositivity, respectively. In the testis, PhyEx normalized HFD-related macrophage infiltration and increased the expression of steroidogenic enzymes and T synthesis. In the hypothalamus, PhyEx normalized HFD-induced gene expression changes related to inflammation and glucose metabolism, restored GnRH expression, particularly doubling mRNA levels, and regulated expression of molecules related to GnRH release (kisspeptin, dynorphin). Concerning MetS components, PhyEx significantly reduced circulating cholesterol and visceral fat. In multivariate analyses, cholesterol levels resulted as the main factor associated with MetS-related alterations in penile, testicular, and hypothalamic districts. In conclusion, our results show that PhyEx may rescue erectile function, exert anti-inflammatory effects on hypothalamus and testis, and increase LH levels and T production, thus supporting a primary role for lifestyle modification to combat MetS-associated hypogonadism and erectile dysfunction.

The complex association between metabolic syndrome and male hypogonadism

BACKGROUND

The complex association between metabolic syndrome (MetS) and male hypogonadism is well established. A number of observational studies show that low testosterone is associated with insulin resistance and an increased risk for diabetes mellitus and MetS in men.

AIMS

To elucidate the association between MetS and male hypogonadism, present epidemiological data on the co-existence of the two comorbidities, enlighten the underlying pathophysiology and appraise the effects of testosterone supplementation therapy (TTh) and lifestyle modifications on MetS and body composition in men.

MATERIALS AND METHODS

Systematic search to PubMed and Medline databases for publications reporting data on association between MetS and male hypogonadism.

RESULTS

Both MetS and male hypogonadism have a high prevalence in the general population and are frequently co-existing e.g. in males with diabetes. Accumulating evidence from animal and human studies suggests that MetS is involved in the pathogenesis of hypogonadism in males as well as the other way around. On the other hand, there is evidence for a favorable effect of testosterone supplementation in testosterone deficient men with MetS and/or diabetes mellitus.

CONCLUSIONS

Studies with superior methodological characteristics are needed in order to establish a role for testosterone supplementation in men with MetS and/or diabetes mellitus.

Hypogonadism and male obesity: Focus on unresolved questions

Obesity, increasing in prevalence globally, is the clinical condition most strongly associated with lowered testosterone concentrations in men and presents as one of the strongest predictors of receiving testosterone treatment. While low circulating total testosterone concentrations in modest obesity primarily reflect reduced concentrations of sex hormone binding globulin, more marked obesity can lead to genuine hypothalamic-pituitary-testicular axis (HPT) suppression. HPT axis suppression is likely mediated via pro-inflammatory cytokine and dysregulated leptin signalling and aggravated by associated comorbidities. Whether oestradiol-mediated negative hypothalamic-pituitary feedback plays a pathogenic role requires further study. Although the obesity-hypogonadism relationship is bidirectional, the effects of obesity on testosterone concentrations are more substantial than the effects of testosterone on adiposity. In markedly obese men submitted to bariatric surgery, substantial weight loss is very effective in reactivating the HPT axis. In contrast, lifestyle measures are less effective in reducing weight and generally only associated with modest increases in circulating testosterone. In randomized controlled clinical trials (RCTs), testosterone treatment does not reduce body weight, but modestly reduces fat mass and increases muscle mass. Short-term studies have shown that testosterone treatment in carefully selected obese men may have modest benefits on symptoms of androgen deficiency and body composition even additive to diet alone. However, longer term, larger RCTs designed for patient-important outcomes and potential risks are required. Until such trials are available, testosterone treatment cannot be routinely recommended for men with obesity-associated nonclassical hypogonadism. Lifestyle measures or where indicated bariatric surgery to achieve weight loss, and optimization of comorbidities remain first line.

The CATCH checklist to investigate adult-onset hypogonadism

Adult-onset hypogonadism is a syndrome often underdiagnosed, undertreated, or incompletely explored. There are various reasons for this: firstly, undefined age range of men in whom testosterone levels should be investigated and then no definitive serum cutoff point for the diagnosis of hypogonadism; and finally, variable and non-specific signs and symptoms; men and physicians do not pay adequate attention to sexual health. All these factors make the diagnostic criteria for hypogonadism controversial. The evaluation of the clinical features and causes of this syndrome, its link with age, the role of testosterone and other hormone levels, and the presence of any comorbidities are all useful factors in the investigation of this population. The purpose of this manuscript, after an accurate analysis of current literature, is to facilitate the diagnosis of hypogonadism in men through the use of the CATCH acronym and a checklist to offer a practical diagnostic tool for daily clinical practice. A narrative review of the relevant literature regarding the diagnosis of late-onset hypogonadism or adult-onset hypogonadism was performed. PubMed database was used to retrieve articles published on this topic. A useful new acronym CATCH (Clinical features [symptoms] and Causes, Age, Testosterone level, Comorbidities, and Hormones) and a practical checklist to facilitate the evaluation of hypogonadism in aging men were used. The evaluation of the clinical features and causes of hypogonadism, the link with age, the role of Testosterone and other hormones, and the evaluation of comorbidities are important in investigating adult-onset hypogonadism. The CATCH checklist could be helpful for clinicians for an early diagnosis of both hypogonadism and associated comorbidities. We suggest the use of this acronym to advocate the investigation of declining testosterone in aging men.

The safety of available treatments of male hypogonadism in organic and functional hypogonadism

INTRODUCTION

In the case of primary male hypogonadism (HG), only testosterone (T) replacement therapy (TRT) is possible whereas when the problem is secondary to a pituitary or hypothalamus alteration both T production and fertility can be, theoretically, restored. We here systematically reviewed and discussed the advantages and limits of medications formally approved for the treatment of HG.

AREAS COVERED

Data derived from available meta-analyses of placebo controlled randomized trials (RCTs) were considered and analyzed. Gonadotropins are well-toleratedand their use is mainly limited by higher costs and a more cumbersome treatment schedule than TRT. Available RCTs on TRT suggest that cardiovascular (CV) and venous thromboembolism risk is not a major issue and that prostate safety is guaranteed. The risk of increased hematocrit is mainly limited to the use of short terminjectable preparations.

EXPERT OPINION

In the last few years the concept of 'organic' irreversible HG and 'functional' or age- and comorbidity-related HG has been introduced. This definition is not evidence-based. The majority of RCTs enrolled patients with 'functional' HG. Considering the significant improvement in body composition, glucose metabolism and sexual activity, TRT should not be limited to 'organic' HG, but also offered for 'functional'.

Characteristics of a nationwide cohort of patients presenting with isolated hypogonadotropic hypogonadism (IHH)

OBJECTIVE

Isolated hypogonadotropic hypogonadism (IHH) is a rare disorder with pubertal delay, normal (normoosmic-IHH, nIHH) or defective sense of smell (Kallmann syndrome, KS). Other reproductive and non-reproductive anomalies might be present although information on their frequency are scanty, particularly according to the age of presentation.

DESIGN

Observational cohort study carried out between January 2008 and June 2016 within a national network of academic or general hospitals.

METHODS

We performed a detailed phenotyping of 503 IHH patients with: (1) manifestations of hypogonadism with low sex steroid hormone and low/normal gonadotropins; (2) absence of expansive hypothalamic/pituitary lesions or multiple pituitary hormone defects. Cohort was divided on IHH onset (PPO, pre-pubertal onset or AO, adult onset) and olfactory function: PPO-nIHH (n = 275), KS (n = 184), AO-nIHH (n = 36) and AO-doIHH (AO-IHH with defective olfaction, n = 8).

RESULTS

90% of patients were classified as PPO and 10% as AO. Typical midline and olfactory defects, bimanual synkinesis and familiarity for pubertal delay were also found among the AO-IHH. Mean age at diagnosis was significantly earlier and more frequently associated with congenital hypogonadism stigmata in patients with Kallmann's syndrome (KS). Synkinesis, renal and male genital tract anomalies were enriched in KS. Overweight/obesity are significantly associated with AO-IHH rather than PPO-IHH.

CONCLUSIONS

Patients with KS are more prone to develop a severe and complex phenotype than nIHH. The presence of typical extra-gonadal defects and familiarity for PPO-IHH among the AO-IHH patients indicates a common predisposition with variable clinical expression. Overall, these findings improve the understanding of IHH and may have a positive impact on the management of patients and their families.

Clomiphene citrate effect in obese men with low serum testosterone treated with metformin due to dysmetabolic disorders: A randomized, double-blind, placebo-controlled study

Context

Low testosterone (T) levels are often found in obese men with impaired glucose tolerance (IGT) and overt type 2 diabetes (T2DM); however, the mechanisms underlying this condition and its correct therapy are still under debate.

Objective

To evaluate the effectiveness of clomiphene citrate (CC) in increasing endogenous T levels in obese men with low serum T and with IGT or T2DM treated with metformin (MET).

Design

Cross-over, randomized, double-blind, placebo-controlled study.

Methods

24 obese men, aged 47.3 ±. 6.3 (range 35–55 years), with low T level (≤3 ng/mL) and naïve diagnosis of IGT or T2DM were included. Subjects were randomized to CC 25 mg/day or placebo (Plac) with MET 2 g/day for 3 months. After a 6-week wash-out period, subjects were moved to the alternative arm for additional 3 months. Clinical evaluation and blood exams performed prior to and at the end of treatment.

Results

Of 24 randomized, 21 were evaluable, classified as IGT (n = 11) or T2DM (n = 10). Compared to baseline levels, T levels increased significantly after 3 months of CC treatment (3.03±0.80 to 5.99±1.67 ng/mL P<0.001) but not after the Plac treatment (2.87±0.78 to 3.09±0.84 ng/mL P<0.001 between the treatments). T changes were similar in IGT and T2DM subjects. Gonadotropins as well raised significantly after CC treatment (LH 3.83±1.45 to 8.53±6.40 mU/mL; FSH 4.84±1.67 to 10.15±5.08 mU/mL P<0.001 respectively), whereas no changes for LH (3.51±1.59 to 3.63±1.39 mU/mL) but a smooth increased for FSH (4.61±2.49 to 5.39±2.65 mU/mL; P = 0.004) were shown after Plac treatment (LH P = 0.001 and FSH P = 0.002 between treatments). Furthermore, fasting glucose (106.8±23.2 to 101.1±25.7 mg/dL; P = 0.004), insulin (19.3±12.1 to 15.6±10.1 μU/mL; P = 0.010) and HOMA-IR (4.94±2.89 to 3.69±2.12; P = 0.001) decreased significantly during the CC treatment period, whereas no significant changes were observed in any of these parameters in the Plac treatment.

Conclusions

A low dose of CC therapy was able to significantly increase serum T levels in all participants with mild modifications of clinical and metabolic parameters.

Trial registration

EudraCT 2011-000439-10

Obesity-related hypogonadism: a reversible condition

Obesity is associated with hypogonadism. While this association is widely accepted, the underlying mechanisms remain unclear. Furthermore, obesity is a risk factor for hypogonadism and conversely hypogonadism may be a risk factor for obesity. We present the case of a morbidly obese man aged 30 years with hypogonadotrophic hypogonadism that underwent a Roux-en-Y gastric bypass operation. Following the surgical treatment of his obesity, the testosterone level returned to normal with improvements in hypogonadal symptoms, which allowed discontinuation of exogenous testosterone therapy. This case report demonstrates reversal of hypogonadism following weight loss with restoration of gonadal function.

Benign prostatic enlargement can be influenced by metabolic profile: results of a multicenter prospective study

Background

In last years Metabolic Syndrome (MetS) has been closely associated to Benign Prostatic Enlargement (BPE) Aim of our study is to evaluate the effect of MetS and each single MetS parameter on prostate growth in men surgically treated for BPE.

Methods

Overall, 379 men were prospectively enrolled in two tertiary referral centers. Calculated prostate volume (PV) was measured with transrectal US defining the antero-posterior (AP), the cranio-caudal (CC) and the latero-lateral (LL) diameters through the ellipsoid formula, while raw PV was calculated by suprapubic US. MetS was defined according to the NCEP-ATPIII criteria.

Results

One-hundred and forty men (36.9%) were affected by MetS. The number of MetS parameters (0 to 5) and the presence of MetS were correlated with the calculated PV. The number of MetS parameters were also directly related to increasing prostate diameters. At the binary logistic regression, MetS resulted associated to high (>60 cc) raw and calculated PV. Moreover, multivariate analysis suggested that AP diameter was mainly correlated with HDL cholesterol (r:-0.3103, p = 0.002) CC diameter with triglycerides (r:-0.191, p = 0.050) and LL diameter with systolic blood pressure (r:0.154, p = 0.044). However, at the binary logistic regression, only low HDL Cholesterol was the main determinant for the enlargement of all diameters and consequently of the whole PV.

Conclusions

Metabolic factors, specially dyslipidemia, could play a central role in the pathogenesis and progression of BPE/LUTS. Interventional studies are needed to evaluate the impact of early treatment of dyslipidemia on progression of LUTS/BPH.