Sex hormones and sexual function in obese men losing weight

Assessing the Prevalence of Male Obesity-Associated Gonadal Dysfunction in Severe Obesity: A Focus on the Impact of Bariatric Surgery and Surgical Approaches

PURPOSE

Obesity is an important risk factor for secondary hypogonadism in men. Several studies evaluated the impact of bariatric surgery on gonadal function in men, proving an improvement in testosterone levels, without yet a global consensus on the impact of different surgical approaches. Objectives of the study are: to estimate the prevalence of obesity-associated gonadal dysfunction among men with severe obesity; to evaluate the response to bariatric surgery in terms of resolution of this condition, distinguishing between restrictive and restrictive-malabsorptive surgery.

METHODS

We conducted a retrospective evaluation of 413 males with severe obesity (BMI 44.7 ± 8.3 kg/m2). A subgroup of them (61.7%) underwent bariatric surgery. Anthropometric assessment (weight, BMI, waist and hip circumference), metabolic (glyco-lipidic asset and urate) and hormonal (morning gonadotropin and total testosterone) assessments were carried out at baseline and 3-6 months post-surgery.

RESULTS

Using a TT threshold of 2.64 ng/ml, 256 out of 413 (62%) patients were categorized as having biochemical hypogonadism. At multivariate analysis, the only parameter significantly associated with biochemical hypogonadism, was BMI value (p = 0.001). At 3-6 months after surgery, during the acute weight loss phase, only 20.1% of patients still had biochemical hypogonadism. At multivariate analysis, which included age, presurgical BMI, pre-surgical TT, surgical approach and %EWL, presurgical TT levels (p = 0.0004), %EWL (p = 0.04), and mixed restrictive-malabsorptive surgery (p = 0.01), were independently associated with the recovery of gonadal function.

CONCLUSIONS

The results of this study underscore the potential reversibility of obesity-associated gonadal dysfunction through bariatric surgery, highlighting the importance of considering surgical approach.

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.

Meta-analysis and construction of simple-to-use nomograms for approximating testosterone levels gained from weight loss in obese men

BACKGROUND

Obesity-induced hypogonadism, which manifests as erectile dysfunction and a lack of libido, is a less visible and under-recognized obesity-related disorder in men.

OBJECTIVE

We examined the impact of weight loss on total (TT) and free testosterone (FT) levels, and constructed nomograms to provide an easy-to-use visual aid for clinicians.

MATERIALS AND METHODS

Meta-analysis was conducted using RevMan (v5.3) and expressed in standardized mean differences (SMD) for testosterone. Parallel-scale nomograms were constructed from baseline and target body mass index values to estimate the gain in testosterone.

RESULTS

In total, 44 studies were included, comprising 1,774 participants and 2,159 datasets, as some studies included several datasets at different time points. Weight loss was controlled by low calorie diet (LCD) in 19 studies (735 participants, 988 datasets), by bariatric surgery (BS) in 26 studies (1,039 participants, 1,171 datasets), and by both in one study. The median follow-up was 26 weeks (interquartile range = 12-52). The range of baseline mean age was 21-68 yr, BMI: 26.2-71.2 kg/m2 , TT: 7-20.2 nmol/L and FT: 140-583 pmol/L. TT levels increased after weight loss by LCD: SMD (95%CI) = 2.5 nmol/L (1.9-3.1) and by BS: SMD = 7.2 nmol/L (6.0-8.4); the combined TT gain was 4.8 nmol/L (3.9-5.6). FT levels increased after weight reduction by LCD: SMD = 19.9 pmol/L (7.3-32.5) and by BS: SMD = 58.0 pmol/L (44.3-71.7); the combined gain was 42.2 pmol/L (31.4-52.9). Greater amounts of total and free testosterone could be gained by weight loss in men with higher baseline BMI, or lower levels of SHBG, TT and FT, while gain in TT was relatively greater in older and FT in younger age. Age-stratified nomograms revealed that compared to older men (> 40 yr), younger men (≤ 40 yr) gained less TT but more FT for a given weight loss.

DISCUSSION AND CONCLUSION

Both TT and FT levels increased after weight loss, relatively greater with higher baseline BMI, or lower levels of SHBG, TT and FT. Nomograms constructed from a large number of participants with a wide range of BMI and testosterone values provide an evidence-based and simple-to-use tool in clinical practice.

Improvements in Sperm Motility Following Low- or High-Intensity Dietary Interventions in Men With Obesity

INTRODUCTION

Obesity increases risks of male infertility, but bariatric surgery does not improve semen quality. Recent uncontrolled studies suggest that a low-energy diet (LED) improves semen quality. Further evaluation within a randomized, controlled setting is warranted.

METHODS

Men with obesity (18-60 years) with normal sperm concentration (normal count) (n = 24) or oligozoospermia (n = 43) were randomized 1:1 to either 800 kcal/day LED for 16 weeks or control, brief dietary intervention (BDI) with 16 weeks' observation. Semen parameters were compared at baseline and 16 weeks.

RESULTS

Mean age of men with normal count was 39.4 ± 6.4 in BDI and 40.2 ± 9.6 years in the LED group. Mean age of men with oligozoospermia was 39.5 ± 7.5 in BDI and 37.7 ± 6.6 years in the LED group. LED caused more weight loss than BDI in men with normal count (14.4 vs 6.3 kg; P < .001) and men with oligozoospermia (17.6 vs 1.8 kg; P < .001). Compared with baseline, in men with normal count total motility (TM) increased 48 ± 17% to 60 ± 10% (P < .05) after LED, and 52 ± 8% to 61 ± 6% (P < .0001) after BDI; progressive motility (PM) increased 41 ± 16% to 53 ± 10% (P < .05) after LED, and 45 ± 8% to 54 ± 65% (P < .001) after BDI. In men with oligozoospermia compared with baseline, TM increased 35% [26] to 52% [16] (P < .05) after LED, and 43% [28] to 50% [23] (P = .0587) after BDI; PM increased 29% [23] to 46% [18] (P < .05) after LED, and 33% [25] to 44% [25] (P < .05) after BDI. No differences in postintervention TM or PM were observed between LED and BDI groups in men with normal count or oligozoospermia.

CONCLUSION

LED or BDI may be sufficient to improve sperm motility in men with obesity. The effects of paternal dietary intervention on fertility outcomes requires investigation.

Effect of surgical, medical, and behavioral weight loss on hormonal and sexual function in men: a contemporary narrative review

This review explores the mechanisms and ramifications of weight loss achieved through lifestyle modifications, medical treatments, and bariatric surgery on testosterone levels and sexual health. Obesity significantly affects the hypothalamic-pituitary-gonadal axis in men, leading to diminished libido and erectile dysfunction. Here, we delve into the physiological disruptions caused by this imbalance and the intricate interplay of hormonal factors contributing to the dysregulation associated with obesity to comprehensively grasp the consequences of weight loss via diverse mechanisms. Lifestyle modifications involving dietary adjustments and regular exercise represent a widely employed and efficacious means of weight loss. While adherence demands discipline, our review scrutinizes various studies specifically investigating the impact of weight loss, attained through lifestyle modifications, on serum hormone levels and sexual function. Notably, several randomized controlled trials within the existing body of literature corroborate the enhancement of testosterone levels and sexual function consequent to weight loss through lifestyle modifications. The realm of medical management in addressing obesity is growing, notably propelled by the popularity of pharmacotherapy. Despite its prevalence, the current literature exploring the effects of weight loss medications on men remains insufficient. Nonetheless, we examine available studies on the medical management of obesity and its implications for sexual health, emphasizing pivotal avenues requiring further investigation. Bariatric surgery stands as an effective approach for individuals seeking substantial weight loss. Our review assesses existing literature that evaluates the impact of various surgical techniques on serum hormone levels, sexual function, and semen parameters. Despite certain limitations, the available body of evidence suggests enhancements in hormone levels and sexual function post-surgery, with semen parameters generally exhibiting minimal changes. This review critically evaluates the landscape of weight loss and its correlation with sexual function, while highlighting crucial areas necessitating future research endeavors.

Positive effects of dietary supplementation with nutraceuticals on male subclinical hypogonadism: a pilot study

BACKGROUND

Lifestyle modifications (i.e., physical activity [PA] and lower dietary intake) often are not sufficient to improve testosterone (TE) levels and promote weight loss in men with metabolic hypogonadism. The aim of the study was to investigate the effects of a nutraceutical formulation containing myoinositol, alpha lipoic acid, folic acid and SelectSIEVE® as add-on treatment to lifestyle modifications in improving obesity-related subclinical hypogonadism.

METHODS

Body composition, insulin resistance, testicular and erectile function were investigated in 15 males (age=39.5±14.5 years; Body Mass Index [BMI]=30.2±3.8 kg/m2, with subclinical hypogonadism (TE levels <14 and normal luteinizing hormone [LH]). After a run-in three months unsupervised PA period (T1), the nutraceutical supplement was administered two-times per day for three additional months (T2).

RESULTS

BMI, the percentage fat mass, insulinemia and Homeostasis Model Assessment Index (P<0.01) along with glycemia (P<0.05) were significantly reduced at T2 compared to T1, respectively; fat free mass (FFM) was significantly higher at T2 compared to T1 (P<0.01). Also, TE, LH and 5-item international index of erectile function score were significantly increased at T2 compared to T1 (P<0.01), respectively.

CONCLUSIONS

The combination of unsupervised PA and nutraceutical supplement improves body composition, insulin sensitivity and TE production in overweight-obese men with metabolic hypogonadism. Further controlled studies in the long-term are warranted to elucidate potential changes in fertility.

Malathion or diazinon exposure and male reproductive toxicity: a systematic review of studies performed with rodents

Malathion and diazinon are pesticides commonly used in agriculture to avoid insects that damage crops; however, they may cause impairment to the male genital system of exposed humans. The present work carried out a systematic review of the literature concerning the primary studies that assessed the reproductive effects resulting from male rats and mice exposed to malathion or diazinon. The search for articles was performed on the databases PubMed, LILACS, Scopus, and SciELO, using different combinations of the search terms "malathion," "diazinon," "mice," "rats," "male reproduction," "fertility," and "sperm," followed by the Boolean operators AND or OR. The results obtained indicate that both pesticides act as reproductive toxicants by reducing sperm quality, diminishing hormonal concentrations, inducing increased oxidative stress, and provoking histopathological damage in reproductive organs. Then, the exposure to malathion and diazinon may provoke diminished levels of testosterone by increasing acetylcholine stimulation in the testis through muscarinic receptors, thus, providing a reduction in steroidogenic activity in Leydig cells, whose effect is related to lower levels of testosterone in rodents, and consequently, it is associated with decreased fertility. Considering the toxic effects on the male genital system of rodents and the possible male reproductive toxicity in humans, it is recommended the decreased use of these pesticides and their replacement for others that show no or few toxic effects for non-target animals.

Adipose Tissue Dysfunction and Obesity-Related Male Hypogonadism

Obesity is a chronic illness associated with several metabolic derangements and comorbidities (i.e., insulin resistance, leptin resistance, diabetes, etc.) and often leads to impaired testicular function and male subfertility. Several mechanisms may indeed negatively affect the hypothalamic–pituitary–gonadal health, such as higher testosterone conversion to estradiol by aromatase activity in the adipose tissue, increased ROS production, and the release of several endocrine molecules affecting the hypothalamus–pituitary–testis axis by both direct and indirect mechanisms. In addition, androgen deficiency could further accelerate adipose tissue expansion and therefore exacerbate obesity, which in turn enhances hypogonadism, thus inducing a vicious cycle. Based on these considerations, we propose an overview on the relationship of adipose tissue dysfunction and male hypogonadism, highlighting the main biological pathways involved and the current therapeutic options to counteract this condition.

The AP-1 family of transcription factors are important regulators of gene expression within Leydig cells

PURPOSE

Members of the AP-1 family of transcription factors are immediate early genes being modulated by different extracellular signals. The aim of this review is to highlight the important roles of AP-1 members in transcriptional regulation of genes important for testicular Leydig cell function and male testosterone production.

METHODS

A search of the relevant literature was performed in Google Scholar and NCBI Pubmed for AP-1 members and Leydig cells. Additional information was accessed from references of relevant articles. Only primary data from original peer-reviewed articles was considered for this review.

RESULTS

Different signaling pathways important for Leydig cells' functions are involved in the regulation of the activity of AP-1 members. These transcription factors participate in the regulation of genes related to different biological processes important for Leydig cells.

CONCLUSIONS

We conclude that members of the AP-1 family of transcription factors play critical roles in the regulation of Leydig cell proliferation, steroidogenesis, and cell-to-cell communication.

The Mechanisms and Management of Age-Related Oxidative Stress in Male Hypogonadism Associated with Non-communicable Chronic Disease

Androgens have diverse functions in muscle physiology, lean body mass, the regulation of adipose tissue, bone density, neurocognitive regulation, and spermatogenesis, the male reproductive and sexual function. Male hypogonadism, characterized by reduced testosterone, is commonly seen in ageing males, and has a complex relationship as a risk factor and a comorbidity in age-related noncommunicable chronic diseases (NCDs), such as obesity, metabolic syndrome, type 2 diabetes, and malignancy. Oxidative stress, as a significant contributor to the ageing process, is a common feature between ageing and NCDs, and the related comorbidities, including hypertension, dyslipidemia, hyperglycemia, hyperinsulinemia, and chronic inflammation. Oxidative stress may also be a mediator of hypogonadism in males. Consequently, the management of oxidative stress may represent a novel therapeutic approach in this context. Therefore, this narrative review aims to discuss the mechanisms of age-related oxidative stress in male hypogonadism associated with NCDs and discusses current and potential approaches for the clinical management of these patients, which may include conventional hormone replacement therapy, nutrition and lifestyle changes, adherence to the optimal body mass index, and dietary antioxidant supplementation and/or phytomedicines.

Effect of weight loss on erectile function in men with overweight or obesity: A meta-analysis of randomised controlled trials

Obesity and overweight are independent risk factors of erectile dysfunction (ED). It is controversial whether weight loss can improve erectile function. We thereby performed this meta-analysis to clarify the therapeutic effect of weight loss on erectile function in overweight or obese men. Literature search was conducted on databases including Cochrane Library, Embase, Web of Science and PubMed to obtain all relevant English articles published before March 1, 2021. The primary outcome was final International Index of Erectile Function (IIEF) score or change in IIEF score. The secondary outcome was final body weight and body mass index (BMI) or change in body weight and BMI. After screening, 5 studies with 619 participants were enrolled in our meta-analysis. Our result showed that the mean difference in body weight between weight loss group and control group was -18.07 kg with p < .01, and the mean difference in BMI was -9.6 kg/m² with p < .01. The mean difference of IIEF between weight loss group and control group was 1.99 with p < .01. This meta-analysis showed that weight loss could improve erectile function in overweight or obese men. Losing weight could serve as an adjuvant therapy for ED.

Examining the effects of calorie restriction on testosterone concentrations in men: a systematic review and meta-analysis

CONTEXT

Testosterone concentrations decline with age, and lower testosterone concentrations are associated with several morbidities, including sexual dysfunction, obesity, type 2 diabetes mellitus (T2DM), and metabolic syndrome.

OBJECTIVE

Because dietary habits play a critical role in weight regulation and T2DM management, the aim of this systematic review and meta-analysis was to summarize and critically evaluate the evidence from randomized controlled trials to determine the effects of calorie restriction (CR) on testosterone concentrations in men.

DATA SOURCES

A literature search was conducted across 4 databases, from their inception until March 2020.

DATA EXTRACTION

The screening and data extraction were completed by 2 authors independently, and in a blinded manner, according to a priori inclusion and exclusion criteria.

DATA ANALYSIS

Of the 4198 studies identified from the initial search, 7 randomized controlled trials were included for data extraction. Significant increases in total testosterone concentrations were reported in 3 of 4 studies in which CR was examined with overweight or obese men, compared with the control groups. Significant decreases in total testosterone concentrations were reported in 2 of 3 studies in which the effects of CR were examined with normal-weight, healthy men, compared with the control groups. In all 4 studies that examined the effect of CR on sex hormone-binding globulin concentrations, the intervention significantly increased sex hormone-binding globulin concentrations compared with that of the control groups irrespective of body composition.

CONCLUSION

This systematic review and meta-analysis provide some evidence that CR affects testosterone concentrations in men and this effect depends on their body mass index. PROSPERO registration no. CRD42020173102.

Obesity and reproduction: a committee opinion

The purpose of this American Society for Reproductive Medicine Practice Committee report is to provide clinicians with principles and strategies for the evaluation and treatment of couples with infertility associated with obesity. This revised document replaces the Practice Committee document titled "Obesity and reproduction: an educational bulletin" last published in 2015 (Fertil Steril 2015;104:1116-26).

Anti-Müllerian hormone concentration as an indicator of female general health status: a cross-sectional study

RESEARCH QUESTION

To evaluate the correlation between clinical and hormonal parameters and comorbidity burden in Caucasian women presenting for fertility treatment.

DESIGN

Monocentric cross-sectional study including a cohort of 3163 Caucasian women seeking medical care for fertility treatment. All patients underwent centralized laboratory testing for hormonal assessment. Complete clinical and laboratory data from the entire cohort were retrospectively analysed. Comorbidity burden score was assessed by the Charlson Comorbidity Index (CCI; categorized as 0 versus 1 versus ≥2).

RESULTS

Descriptive statistics and regression models tested the associations between clinical and laboratory parameters and CCI. Among the entire cohort of patients, a CCI = 0 was found in 2977 women (94.1%), and CCI = 1 and CCI ≥2 were found in 113 (3.6%) and 73 (2.3%) patients, respectively. Age (P = 0.009), gravidity (P = 0.001), anti-Müllerian hormone (AMH, P < 0.001) and TSH (P = 0.003) values were significantly different among CCI groups. In regression models, age at presentation and AMH emerged as independent indicators of CCI ≥ 1. Age at presentation <36 years (odds ratio [OR] 1.742, 95% confidence interval [CI] 1.284-2.364) and an AMH concentration ≤2.3 ng/ml (OR 1.864, 95% CI 1.29-2.69) were the most informative cut-off values for CCI ≥ 1 in the study population.

CONCLUSIONS

A younger age at presentation and lower AMH concentrations are significant independent indicators of decreased general health in women requiring clinical evaluation for fertility treatment. As observed for sperm parameters in men, AMH might serve as a proxy of women's general health status.

How Would You Manage This Male Patient With Hypogonadism? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Male hypogonadism is defined as an abnormally low serum testosterone concentration or sperm count. As men age, often in the context of obesity and other comorbid conditions, serum testosterone levels may decrease. Normalizing serum testosterone levels in male adults with hypogonadism may improve symptoms related to androgen deficiency, but controversies exist regarding the long-term benefits and risks of hormone supplementation in this setting. In 2020, the American College of Physicians published a clinical guideline for the use of testosterone supplementation in adult men based on a systematic review of available evidence. Among their recommendations were that clinicians discuss whether to initiate testosterone treatment in men with age-related low testosterone with sexual dysfunction who want to improve sexual function and not initiate testosterone treatment in men with age-related low testosterone to improve energy, vitality, physical function, or cognition. Here, two clinicians with expertise in this area, one a generalist and the other an endocrinologist, debate the management of a patient with sexual symptoms and a low serum testosterone level. They discuss the diagnosis of male hypogonadism, the indications for testosterone therapy, its potential benefits and risks, how it should be monitored, and how long it should be continued.

Effect of bariatric surgery on endogenous sex hormones and sex hormone-binding globulin levels: a systematic review and meta-analysis

BACKGROUND

Most studies have shown beneficial effect of bariatric surgery (BS) on serum levels of sex hormones.

OBJECTIVE

A systematic review and meta-analysis was conducted to examine the magnitude of possible changes in levels of sex hormones following BS.

SETTINGS

Electronic databases were searched, including PubMed, Scopus, Web of Science, and Embase, for relevant studies.

METHODS

The heterogeneity of the studies was examined by χ² tests and the degree of heterogeneity was estimated using I² statistic.

RESULTS

The results of pooled analyses revealed that BS caused a significant increase in luteinizing hormone (LH), follicular stimulating hormone (FSH), total testosterone (TT), and sex hormone binding globulin (SHBG) levels and conversely, decreased dehydroepiandrosterone (DHEA) and estradiol (E2) levels in males. For females, BS significantly increased LH, FSH, and SHBG levels and conversely, decreased androstenedione (AE), E2 and TT levels. Additionally, the level of progesterone (P), prolactin (PRL), free testosterone (FT) and dehydroepiandrosterone sulfate (DHEA-S) showed no significant changes in patients who had undergone BS.

CONCLUSION

BS changed most sex hormones levels including LH, FSH, TT, SHBG, AE, DHEA, and E2. It seems that BS is able to exert substantial impacts on sex hormones levels and as well as sexual function, however, larger, and more precise trials are required to specifically focus on these claims.

The ketogenic diet corrects metabolic hypogonadism and preserves pancreatic ß-cell function in overweight/obese men: a single-arm uncontrolled study

BACKGROUND

Overweight and obesity are increasingly spread in our society. Low testosterone levels are often present in these patients, the so-called metabolic hypogonadism, that further alters the metabolic balance in a sort of vicious cycle. Very low-calorie ketogenic diet (VLCKD) has been reported to efficiently reduce body weight, glycaemia, and the serum levels of insulin, glycated hemoglobin, but its effects on β-cell function and total testosterone (TT) levels are less clear.

AIM

To evaluate the effects of VLCKD on markers suggested to be predictive of β-cell dysfunction development, such as proinsulin or proinsulin/insulin ratio, and on TT values in a cohort of overweight or obese nondiabetic male patients with metabolic hypogonadism.

METHODS

Patients with overweight or obesity and metabolic hypogonadism underwent to VLCKD for 12 weeks. Anthropometric parameters, blood testing for the measurement of glycaemia, insulin, C-peptide, proinsulin, TT, calculation of body-mass index (BMI), and HOMA index were performed before VLCKD and after 12 weeks.

RESULTS

Twenty patients (mean age 49.3 ± 5.2 years) were enrolled. At enrollement all patients presented increased insulin, HOMA index, C-peptide, and proinsulin levels, whereas the proinsulin/insulin ratio was within the normal values. After VLCKD treatment, body weight and BMI significantly decreased, and 14.9 ± 3.9% loss of the initial body weight was achieved. Glycaemia, insulin, HOMA index, C-peptide, and proinsulin significantly decreased compared to pre-VLCKD levels. Serum glycaemia, insulin, C-peptide, and proinsulin levels returned within the normal range in all patients. No difference in the proinsulin/insulin ratio was observed after VLCKD treatment. A mean increase of 218.1 ± 53.9% in serum TT levels was achieved and none of the patients showed TT values falling in the hypogonadal range at the end of the VLCKD treatment.

CONCLUSIONS

This is the first study that evaluated the effects of VLCKD on proinsulin, proinsulin/insulin ratio, and TT levels. VLCKD could be safely used to improve β-cell secretory function and insulin-sensitivity, and to rescue overweight and obese patients from β-cell failure and metabolic hypogonadism.

Dynamic behavior of metabolic syndrome progression: a comprehensive systematic review on recent discoveries

BACKGROUND

The assessment of the natural history of metabolic syndrome (MetS) has an important role in clarifying the pathways of this disorder.

OBJECTIVE

This study purposed to provide a rational statistical view of MetS progression pathway.

METHODS

We performed a systematic review in accordance with the PRISMA Statement until September 2019 in the Medline/PubMed, Scopus, Embase, Web of Science and Google Scholar databases. From the 68 found studies, 12 studies were eligible for review finally.

RESULTS

The selected studies were divided in 2 groups with Markovian and non-Markovian approach. With the Markov approach, the most important trigger for the MetS chain was dyslipidemia with overweight/obesity in the under-50 and with hypertension in the over-50 age group, where overweight/obesity was more important in women and hypertension in men. In non-Markov approach, the most common trigger was hypertension. Transition probability (TP) from no component to MetS were higher in all Markovian studies in men than in women. In the Markovians the combination of dyslipidemia with overweight/obesity and in non-Markovians, hyperglycemia with overweight/obesity were the most common combinations. Finally, the most important components, which predict the MetS, were 2-component states and hyperglycemia in Markovian approach and overweight/obesity in non-Markovians.

CONCLUSIONS

Among the components of the MetS, dyslipidemia and hypertension seems to be the main developer components in natural history of the MetS. Also, in this chain, the most likely combination over time that determines the future status of people seems to be the combination of dyslipidemia with obesity or hyperglycemia. However, more research is needed.

Association Between Low Serum Testosterone and the Development of Metabolic Syndrome in Elderly Taiwanese Men

PURPOSE

To assess the association between serum testosterone (T) and metabolic syndrome (MS) in different age groups in Taiwanese men.

MATERIALS AND METHODS

Male participants, regardless of age or any underlying disease, were identified from MJ Health Screening Center in Taiwan from 2007 to 2016 for this cross-sectional study. They were divided into three groups according to age, and further classified according to MS diagnosis. Basic patient characteristics with relevant parameters were obtained. One-way ANOVA of mean T values between different numbers of measures that exceeds the cut-off values of MS components was performed to assess the relationship of T and MS. Logistic regression analysis was also used to estimate the risk for MS with each increment in T, age, and BMI.

RESULTS

A total of 4,931 men were included. The MS group had significantly lower serum T levels compared to the non-MS group in each age group. The one-way ANOVA found the mean value of T was significantly higher in patients without MS component (6.19±2.12 ng/mL) than those with 1-5 MS components (with one MS component: 5.48±2.13 ng/mL, two MS components: 4.93±2.03 ng/mL, three MS components: 4.37±1.60 ng/mL, four MS components: 4.13±2.89 ng/mL, five MS components: 3.74±1.27 ng/mL, and P<0.001). There was no significant difference between the patients with three components and the patients with four or five components. Logistic regression models with age stratification showed T with lower odds ratio (OR) for MS after adjusting for BMI in those ≥65 years old (OR=0.693; 95% CI=0.559-0.858; P<0.001); 50-64 years old (OR=0.868; 95% CI=0.802-0.940; P<0.001) and <50 years old (OR=0.810; 95% CI=0.758-0.865; P<0.001).

CONCLUSION

Lower serum T was strongly associated with MS, with the predictive value increasing with age in Taiwanese men.

Barocrinology: The Endocrinology of Obesity from Bench to Bedside

Obesity has reached pandemic proportions. Hormonal and metabolic imbalances are the key factors that lead to obesity. South Asian populations have a unique phenotype, peculiar dietary practices, and a high prevalence of consanguinity. Moreover, many lower middle-income countries lack appropriate resources, super-specialists, and affordability to manage this complex disorder. Of late, there has been a substantial increase in both obesity and diabesity in India. Thus, many more patients are being managed by different types of bariatric procedures today than ever before. These patients have many types of endocrine and metabolic disturbances before and after bariatric surgery. Therefore, these patients should be managed by experts who have knowledge of both bariatric surgery and endocrinology. The authors propose “Barocrinology”, a novel terminology in medical literature, to comprehensively describe the field of obesity medicine highlighting the role of knowing endocrine physiology for understating its evolution, insights into its complications and appreciating the changes in the hormonal milieu following weight loss therapies including bariatric surgery. Barocrinology, coined as a portmanteau of “baro” (weight) and endocrinology, focuses upon the endocrine and metabolic domains of weight physiology and pathology. This review summarizes the key pointers of bariatric management from an endocrine perspective.

Signaling pathways of dietary energy restriction and metabolism on brain physiology and in age-related neurodegenerative diseases

Several laboratory animal models have shown that dietary energy restriction (ER) can promote longevity and improve various health aspects in old age. However, whether the entire spectrum of ER-induced short- and long-term physiological and metabolic adaptions is translatable to humans remains to be determined. In this review article, we present recent evidence towards the elucidation of the impact of ER on brain physiology and in age-related neurodegenerative diseases. We also discuss modulatory influences of ER on metabolism and overall on human health, limitations of current experimental designs as well as future perspectives for ER trials in humans. Finally, we summarize signaling pathways and processes known to be affected by both aging and ER with a special emphasis on the link between ER and cellular proteostasis.

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.

Exposure to low doses of malathion during juvenile and peripubertal periods impairs testicular and sperm parameters in rats: Role of oxidative stress and testosterone

Malathion is an organophosphate insecticide used in agriculture and for controlling vector-borne diseases such as Zika. Humans can be exposed to malathion by means of ingestion of contaminated food. The juvenile and peripubertal periods are a large window of vulnerability to the action of toxic agents. The aim of the present study was to evaluate the effects of low doses of malathion during the development of testes in the juvenile and peripubertal periods in rats. For this purpose, 45 male Wistar rats (postnatal day (PND) 25) were assigned to 3 experimental groups and treated for 40 days. The animals were exposed daily to malathion 10 mg/kg (M10 group) or 50 mg/kg (M50 group) diluted in 0.9 % saline via gavage. The control group received only the vehicle. On the 40th experimental day, the rats were anaesthetized and euthanized. The blood was collected for determination of testosterone concentration. The testes were removed and weighed. Spermatozoa from the vas deferens were used for sperm morphological analysis. The testes were used for evaluation of sperm count and oxidative stress status to determine the inflammatory profile and analysis of tissue constitution. The results showed that both malathion doses reduced the sperm count and increased the number of abnormal sperms. Furthermore, both doses altered the spermatogenetic process, delayed spermiogenesis, reduced the Leydig and Sertoli cell number and increased the thickness of tunica albuginea. The M10 group presented increased IL-10 levels and reduced GSH levels. These parameters did not change in the M50 group. However, the M50 group showed an increase in the number of abnormal seminiferous tubules, a decrease in plasma testosterone concentration and an increase in lipid peroxidation in the testes. In conclusion, the exposure to low doses of malathion during juvenile and peripubertal development resulted in testicular toxicity and compromised the testicular morphology and function.

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.

Very-low-calorie ketogenic diet (VLCKD) in the management of metabolic diseases: systematic review and consensus statement from the Italian Society of Endocrinology (SIE)

BACKGROUND

Weight loss is a milestone in the prevention of chronic diseases associated with high morbility and mortality in industrialized countries. Very-low calorie ketogenic diets (VLCKDs) are increasingly used in clinical practice for weight loss and management of obesity-related comorbidities. Despite evidence on the clinical benefits of VLCKDs is rapidly emerging, some concern still exists about their potential risks and their use in the long-term, due to paucity of clinical studies. Notably, there is an important lack of guidelines on this topic, and the use and implementation of VLCKDs occurs vastly in the absence of clear evidence-based indications.

PURPOSE

We describe here the biochemistry, benefits and risks of VLCKDs, and provide recommendations on the correct use of this therapeutic approach for weight loss and management of metabolic diseases at different stages of life.

Is low body mass index a risk factor for semen quality? A PRISMA-compliant meta-analysis

BACKGROUND

Male infertility has become a worldwide public health problem. However, the effect of low body mass index (BMI) is still controversial.

METHODS

Relevant articles in Pubmed, Embase, Web of science, and Wanfang database published until September 2017 were searched without language restriction. We performed a meta-analysis about low BMI and semen parameters containing total sperm count, concentration, semen volume, and sperm motility (overall and progressive), including 709 men with low BMI and 14,622 men with normal BMI.

RESULTS

Thirteen studies were included in this meta-analysis and a total of 15,331 individuals were accumulated. We pooled data from these articles and found standardized weighted mean differences in semen parameters (total sperm count and semen volume) showed significant difference between low BMI and normal BMI.

CONCLUSIONS

This systematic review with meta-analysis has confirmed that there was a relationship between low BMI and semen quality, which suggesting low BMI may be a harmful factor of male infertility. Yet lacking of the raw data may influence the accuracy of the results. Further researches are needed to identify the role of underweight in male sterility.

Klinefelter Syndrome and Diabetes

PURPOSE OF REVIEW

Klinefelter syndrome (KS) is associated with increased insulin resistance and high rates of type 2 diabetes (T2DM). Our aim was to review what is known about the prevalence of diabetes in men with KS, potential mechanisms underlying the observed metabolic phenotype, and the data that are available to guide treatment decisions.

RECENT FINDINGS

The increased prevalence of T2DM seen in men with KS appears to be the result of multiple mechanisms including increased truncal adiposity and socioeconomic disadvantages, but it is likely not a direct consequence of hypogonadism alone. No randomized trials have been conducted to evaluate the impact of testosterone replacement therapy on T2DM in men with KS, but observational data suggest that testosterone replacement is not associated with lower rates of diabetes or improved glycemic control. Metabolic derangements are common in KS, but treatment strategies specific to this population are lacking. Early lifestyle and dietary interventions are likely important. Additional research is needed to dissect the complex interaction between genotype and metabolic phenotype. Collaboration between academic centers caring for men with KS is needed to facilitate the development of evidence-based clinical practice guidelines, which would inform optimal screening and treatment strategies for this patient population.

Metabolic syndrome and smoking are independent risk factors of male idiopathic infertility

Background

Overweight and obesity are known to impact male fertility and are commonly associated with abdominal obesity and metabolic disorders. The association between abdominal obesity or metabolic syndrome with male reproduction has not been fully investigated. Moreover, many factors may interfere with the evaluation of the impact of metabolic syndrome on male fertility. Thus, tobacco is known to alter the spermatic parameters and phenomena linking smoking with metabolic syndrome are therefore complex. The main objective of this study has been to investigate the potential association of metabolic syndrome with male idiopathic infertility given smoking status.

Materiel and methods

The data of this study concerned infertile (n = 96) and fertile (n = 100) men under 45 years of age who have been recruited in the ALIFERT case-control study. Body mass index and waist circumference were measured. Serum triglycerides, cholesterol (total, high density lipoprotein, and low density lipoprotein cholesterol) and fasting blood glucose were assayed. Metabolic syndrome has been diagnosed in the presence of at least three of the following criteria: increased waist circumference, high triglycerides, fasting glucose or arterial blood pressure and low high density lipoprotein cholesterol.

Results

The present study reports that infertile men are in poorer health condition compared to fertile men and are more often smokers. The results of this study suggested metabolic syndrome and smoking to be independent risk factor for idiopathic infertility.

Conclusions

Metabolic syndrome and smoking should systematically be checked at the beginning of medical care in infertile males and personal and multifaceted coaching should be proposed to deal jointly with smoking and metabolic disorders.

Trial registration

NCT01093378 ALIFERT. Registered: March 25, 2010.

How much does obesity affect the male reproductive function?

Obesity is considered a worldwide epidemic disease. Many pathological conditions have been associated to obesity but the evidence relating to impaired fertility in males with obesity are contrasting. The aim of this review was to evaluate the interplay between obesity and male fertility, analyzing evidence from in vitro and in vivo studies to clinical trials. Obesity seems to be responsible of secondary hypogonadism. Here, we propose a new classification including central, peripheral and testicular factors that may affect the hypothalamic-pituitary-gonadal axis. Moreover, some studies demonstrated a direct action of obesity on sperm count and sperm characteristics, mediated by impaired Sertoli cells function, increased scrotal temperature, oxidative stress and accumulation of toxic substances and liposoluble endocrine disruptors in fat tissue. Recent studies have explored obesity-related epigenetic effects in sperm cells which may cause diseases in offspring. Moreover, not only in females but also males, obesity has been linked to reduced outcomes of in vitro fertilization, with a reduction of pregnancy rate and an increase of pregnancy loss. Finally, we reviewed the effects of weight modifications through diet or bariatric surgery on obesity-related reproductive dysfunction. In this regard, several studies have demonstrated that weight loss has been associated with a restoration of gonadal hormones levels.

Metabolic and Endocrine Consequences of Bariatric Surgery

Obesity is one of the most serious worldwide epidemics of the twenty-first century according to the World Health Organization. Frequently associated with a number of comorbidities, obesity threatens and compromises individual health and quality of life. Bariatric surgery (BS) has been demonstrated to be an effective treatment to achieve not only sustained weight loss but also significant metabolic improvement that goes beyond mere weight loss. The beneficial effects of BS on metabolic traits are so widely recognized that some authors have proposed BS as metabolic surgery that could be prescribed even for moderate obesity. However, most of the BS procedures imply malabsorption and/or gastric acid reduction which lead to nutrient deficiency and, consequently, further complications could be developed in the long term. In fact, BS not only affects metabolic homeostasis but also has pronounced effects on endocrine systems other than those exclusively involved in metabolic function. The somatotropic, corticotropic, and gonadal axes as well as bone health have also been shown to be affected by the various BS procedures. Accordingly, further consequences and complications of BS in the long term in systems other than metabolic system need to be addressed in large cohorts, taking into account each bariatric procedure before making generalized recommendations for BS. In this review, current data regarding these issues are summarized, paying special attention to the somatotropic, corticotropic, gonadal axes, and bone post-operative health.

Can Low SHBG Serum Concentration Be A Good Early Marker Of Male Hypogonadism In Metabolic Syndrome?

INTRODUCTION

In men suffering from metabolic syndrome, accompanying insulin resistance may result in a lowering of sex hormone-binding globulin (SHBG) plasma levels and cause changes in their androgenic status.

AIM

The objective of the research was to assess selected androgens and SHBG plasma levels in males meeting diagnostic criteria for MS compared to healthy males.

PATIENTS AND METHODS

The group consisted of 65 men aged between 40 and 70 years old fitting IDF metabolic syndrome criteria and 84 controls. Dehydroepiandrosterone (DHEA) and its sulphate (DHEA-S), total and free testosterone and SHBG serum levels were evaluated. Calculated free and bioavailable testosterone were estimated using an algorithm proposed by the International Society for the Study of the Aging Male.

RESULTS

Men diagnosed with MS showed a statistically significant decrease in plasma levels of DHEA in comparison to healthy ones: 11.579 (8.39-15.56) vs 14.014 (9.611-17.125) ng/mL; p = 0.0350, SHBG: 47.46 (35.78-62.83) vs 71.965 (54.45-91.56) nM/L; p<0.0001 and total testosterone: 5.2 (3.8-6.5) vs 6.3 (5.4-8.25) ng/mL; p = 0.0001 (values presented as a median with Q1-Q3).

CONCLUSION

The results suggest that SHBG is a good early marker for metabolic dysregulation in MS, considering its strength of association and significance is comparable to, or better than, those of MS criteria.

Obesity, Male Reproductive Function and Bariatric Surgery

Overweight and obesity are associated with several chronic complications, such as type 2 diabetes, arterial hypertension and atherosclerotic cardiovascular diseases, with relevant consequences for patients and public health systems. Reproductive function abnormalities, such as obesity-related secondary hypogonadism, erectile dysfunction and infertility, represent other abnormalities negatively affecting the quality of life of men suffering from obesity but, despite their high prevalence, these are often understated because of a general lack of awareness in clinical practice. Obesity and gonadal function are closely related, with obesity being associated with hypogonadism that is reversed by body weight reduction thus ameliorating reproductive and sexual health. Clinical studies specifically evaluating the impact of non-surgical weight loss on testosterone levels sometimes showed conflicting results, whereas extensive literature has demonstrated that weight loss after bariatric surgery is correlated with an increase in testosterone levels greater than that obtained with only lifestyle interventions, suggesting the role of surgery also for the treatment of hypogonadism in obese male. However, studies concerning the consequences of bariatric surgery on overall reproductive function in the male, including also sexual activity and fertility, are limited and data regarding long-term effects are lacking. Here we present a brief review summarizing the evidence regarding the interplay between obesity and reproductive abnormalities in the obese male, together with the role of bariatric surgery for the treatment of these complications, describing both the positive effects and the limitations of this procedure.

Frontiers in hormone therapy for male infertility

For a significant number of couples worldwide, infertility is a harsh reality. As specialists in male infertility, much of our armamentarium lacks definitive, evidence-based therapies. For years, we have relied on manipulation of the male hormonal axis to treat those men who help carry the burden of infertility in their partnerships. Indeed, male factor infertility is the sole component of infertility in at least 20% of couples. Further compounding this dilemma is that 25% to 50% of males with infertility have no identifiable etiology and thus present a true management conundrum. This manuscript is an attempt to clarify what therapies exist for the treatment of male factor infertility. We have reviewed the relevant infertility literature honing, our focus on hormonal anomalies and their subsequent impact on fertility. Many of the therapies discussed have been utilized in practice for generations. Thus, this article attempts to provide the evidence-based literature to support the continued use of the current treatment paradigm. Furthermore, we recognize that any review beckons a discussion of what challenges and therapies await on the horizon. For instance, there has been significant interest in restoring spermatogenesis after testosterone replacement therapy (TRT). We explore the adverse long-term spermatogenic outcomes associated with TRT, which with the widespread use of TRT, will inevitably present a great challenge for male infertility specialists. Moreover, we discuss the role of varicocelectomy in the treatment of hypogonadism and infertility, review the association between growth hormone (GH) and male fertility and address the challenges presented by the rising prevalence of obesity.

The impact of BMI on sperm parameters and the metabolite changes of seminal plasma concomitantly

The development of male infertility increased rapidly worldwide, which coinciding with the epidemic of obesity. However, the impact of weight abnormalities on sperm quality is still contestable. To assess the correlation between BMI and sperm parameters, we searched relevant articles in PubMed, Embase, Web of science, and Wanfang database published until June 2015 without language restriction. Otherwise, we also recruited some participants who attended fertility clinic as well as some general populations in this report. We performed a systematic review and meta-analysis about BMI and sperm parameters containing total sperm count, concentration, semen volume and sperm motility (overall and progressive). Metabolomic analysis of seminal plasma was performed to explore the mechanism from a new perspective. This study found standardized weighted mean differences (SMD) in sperm parameters (total sperm count, sperm concentration, and semen volume) of abnormal weight groups decreased to different degree compared to normal weight. Dose-response analysis found SMD of sperm count, sperm concentration and semen volume respectively fell 2.4%, 1.3% and 2.0% compared with normal weight for every 5-unit increase in BMI. Metabolomic analysis of seminal plasma showed that spermidine and spermine were likely to play a vital role in the spermatogenesis progress. This systematic review with meta-analysis has confirmed there was a relationship between BMI and sperm quality, suggesting obesity may be a detrimental factor of male infertility.

Effectiveness of testosterone therapy in obese men with low testosterone levels, for losing weight, controlling obesity complications, and preventing cardiovascular events: Protocol of a systematic review of randomized controlled trials

BACKGROUND

The use of testosterone replacement therapy in obese men with low testosterone levels has been controversial. This review aims to analyze the effectiveness of testosterone therapy for weight loss and preventing cardiovascular complications in obese men with low testosterone levels.

METHODS

We will perform a systematic review according to Cochrane Methodology of randomized studies, including crossover studies, wherein patients are allocated into one of the two groups: testosterone therapy and control (no treatment or placebo). The primary outcomes analyzed will be: weight loss, adverse events, quality of life, improvement of libido, control of obesity complications, frequency of cardiovascular events, and deaths. Four general and adaptive search strategies have been created for the following electronic health databases: Embase, Medline, LILACS, and CENTRAL. Two reviewers will independently select the eligible studies, assess the risk of bias, and extract the data from included studies. Similar outcomes measured in at least two trials will be plotted in the meta-analysis using Review Manager 5.3. The quality of evidence of the effect estimate of the intervention for the outcomes that could be plotted in the meta-analysis will be generated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group.

RESULTS

Although testosterone replacement seems to be an attractive treatment modality for obese men with low testosterone, its potential benefits has been refuted by some studies, whose results have not shown significant differences between treated and untreated patients.

CONCLUSION

For obese men with low testosterone concentrations, the proposed systematic review aims to answer the following questions: When compared with no treatment or placebo: Is testosterone therapy safe? Is testosterone therapy effective in promoting weight loss, a sustained reduction in body weight and changes in body composition? Is testosterone effective in improving quality of life, libido, and erectile function? Is testosterone therapy effective in controlling obesity complications and in preventing cardiovascular events?

Cross-sectional association between testosterone, sex hormone-binding globulin and metabolic syndrome: The Healthy Twin Study

OBJECTIVES

This study evaluated an association between testosterone, sex hormone-binding globulin (SHBG) and metabolic syndrome (MetS).We also evaluated the genetic and environmental influences on the association.

DESIGN

Cross-sectional.

SETTING

Community-based study.

PARTICIPANTS

A total of 1098 Korean adult men including 139 monozygotic twin pairs.

MAIN OUTCOME MEASURE

MetS was defined using the National Cholesterol Education Program-Third Adult Treatment Panel (NCEP ATP III) and International Diabetes Federation (IDF) criteria. The associations between MetS and sex hormones were evaluated using linear mixed model and generalized estimating equation model.

RESULTS

After considering covariates such as smoking, alcohol consumption and physical exercises as well as SHBG or testosterone, the risk of MetS defined by NCEP ATP III criteria decreased by 31%, 29%, and 48%, respectively, with 1-standard deviation increase in total testosterone (TT), free testosterone (cFT) and SHBG. Similar findings were revealed with IDF criteria. Metabolic component specific analysis showed that sex hormones were inversely associated with several components of MetS: TT with abdominal obesity, low high-density lipoprotein cholesterol (HDL-C) and high blood pressure; cFT with abdominal obesity and high blood pressure; SHBG with all components except high blood pressure. Cotwin control analysis found an inverse correlation between within-pair differences in testosterone and SHBG levels and within-pair differences in waist circumference only.

CONCLUSION

Both testosterone and SHBG were inversely associated with MetS although the inverse associations with the sex hormones were not consistently found across individual metabolic components. Findings from cotwin analysis suggest a significant contribution of unshared unique environmental effect to the association between testosterone and SHBG and abdominal obesity.

Management of weight loss in obesity-associated male infertility: a spotlight on bariatric surgery

In recent years, there has been a paralleled increase between male obesity and infertility rates. Obesity is associated with impaired hypothalamic-pituitary-gonadal axis, aberrant semen parameters, and subfertility or infertility. Weight loss is strongly recommended for the management of obesity-associated infertility. Lifestyle modifications that include caloric restriction and increased physical activity have a short-lived impact. Bariatric surgery is a better and more durable weight loss alternative. Comprehensive information about the benefits of weight loss on obesity-associated male infertility following bariatric surgery is still emerging. In this review, we discuss the hormonal, physical and environmental mechanism contributing to obesity-associated infertility. We then assess weight loss approaches, which include lifestyle modification, medical and surgical approaches, that can improve fertility in obese men. This review focuses also on bariatric surgery for the management of obese men seeking fertility treatment. Anecdotal evidence suggesting that bariatric surgery can impair fertility is also discussed.

A high-fat diet impairs reproduction by decreasing the IL1β level in mice treated at immature stage

Obesity causes low-grade inflammation that is involved in male infertility. Interleukin 1 beta (IL1β) plays an important role in this process. A high-fat diet (HFD) is the most common cause of obesity. However, the effect of a HFD on IL1β and its consequence in reproduction remain unclear. We established a HFD model in mice treated at immature stage (mice-TIS) and mice treated at mature stage (mice-TMS). Surprisingly, we found that a HFD decreased IL1β levels and was accompanied by an increase in testosterone in mice-TIS, while the reverse results were observed in mice-TMS. In addition, a HFD caused a reduction in testis macrophages and in the expression of inflammasome-related genes and proteins in mice-TIS. Furthermore, we found that IL1β inhibited testosterone secretion through down-regulating the gene expression of P450SCC and P450c17. However, the influence on mice-TIS that were induced by a HFD was recovered by stopping the HFD. In this study, we are the first to report that a HFD impairs the reproductive system by decreasing IL1β and enhancing testosterone levels in mice-TIS, which are different from the effects in mice-TMS. This provides new ideas for the treatment of obesity-induced infertility.

Symptomatic response to testosterone treatment in dieting obese men with low testosterone levels in a randomized, placebo-controlled clinical trial

BACKGROUND

Obese men commonly have reductions in circulating testosterone and report symptoms consistent with androgen deficiency. We hypothesized that testosterone treatment improves constitutional and sexual symptoms over and above the effects of weight loss alone.

METHODS

We conducted a pre-specified analysis of a randomized double-blind, placebo-controlled trial at a tertiary referral center. About 100 obese men (body mass index (BMI)⩾30 kg m^-2) with a repeated total testosterone level ⩽12 nmol l^-1 and a median age of 53 years (interquartile range 47-60) receiving 10 weeks of a very-low-energy diet (VLED) followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of intramuscular testosterone undecanoate (n=49, cases) or matching placebo (n=51, controls). Pre-specified outcomes were the between-group differences in Aging Male Symptoms scale (AMS) and international index of erectile function (IIEF-5) questionnaires.

RESULTS

Eighty-two men completed the study. At study end, cases showed significant symptomatic improvement in AMS score, compared with controls, and improvement was more marked in men with more severe baseline symptoms (mean adjusted difference (MAD) per unit of change in AMS score -0.34 (95% confidence interval (CI) -0.65, -0.02), P=0.04). This corresponds to improvements of 11% and 20% from baseline scores of 40 and 60, respectively, with higher scores denoting more severe symptoms. Men with erectile dysfunction (IIEF-5⩽20) had improved erectile function with testosterone treatment. Cases and controls lost the same weight after VLED (testosterone -12.0 kg; placebo -13.5 kg, P=0.40) and maintained this at study end (testosterone -11.4 kg; placebo -10.9 kg, P=0.80). The improvement in AMS following VLED was not different between the groups (-0.05 (95% CI -0.28, 0.17), P=0.65).

CONCLUSIONS

In otherwise healthy obese men with mild to moderate symptoms and modest reductions in testosterone levels, testosterone treatment improved androgen deficiency symptoms over and above the improvement associated with weight loss alone, and more severely symptomatic men achieved a greater benefit.

Long-Term Effects of a Randomised Controlled Trial Comparing High Protein or High Carbohydrate Weight Loss Diets on Testosterone, SHBG, Erectile and Urinary Function in Overweight and Obese Men

Introduction

Obesity is associated with reduced testosterone and worsened erectile and sexual function in men. Weight loss improves these outcomes. High protein diets potentially offer anthropometric and metabolic benefits, but their effects on reproductive and sexual outcomes is not known.

Aim

To examine the long-term effects of weight loss with a higher protein or carbohydrate diet on testosterone, sex hormone binding globulin, erectile dysfunction, lower urinary tract symptoms and sexual desire in overweight and obese men.

Methods

One-hundred and eighteen overweight or obese men (body mass index 27–40 kg/m², age 20–65 years) were randomly assigned to an energy restricted higher protein low fat (35% protein, 40% carbohydrate, 25% fat; n = 57) or higher carbohydrate low fat diet (17% protein, 58% carbohydrate, 25% fat, n = 61) diet for 52 weeks (12 weeks weight loss, 40 weeks weight maintenance). Primary outcomes were serum total testosterone, sex hormone binding globulin and calculated free testosterone. Secondary outcomes were erectile function as assessed by the International Index of Erectile Function (IIEF) (total score and erectile function domain), lower urinary tract symptoms and sexual desire.

Results

Total testosterone, sex hormone binding globulin and free testosterone increased (P<0.001) and the total IIEF increased (P = 0.017) with no differences between diets (P≥0.244). Increases in testosterone (P = 0.037) and sex hormone binding globulin (P<0.001) and improvements in the total IIEF (P = 0.041) occurred from weeks 0–12 with a further increase in testosterone from week 12–52 (P = 0.002). Increases in free testosterone occurred from week 12–52 (p = 0.002). The IIEF erectile functon domain, lower urinary tract symptoms and sexual desire did not change in either group (P≥0.126).

Conclusions

In overweight and obese men, weight loss with both high protein and carbohydrate diets improve testosterone, sex hormone binding globulin and overall sexual function.

Trial Registration

Anzctr.org.au ACTRN12606000002583

Effect of bariatric surgery on semen parameters and sex hormone concentrations: a prospective study

Obesity has become a major health concern, with a prevalence rate approaching epidemic states. An inverse relationship between men's body weight and semen parameters has been observed, suggesting a favourable role for weight loss in improving fertility. This prospective study included 46 patients undergoing sleeve gastrectomy, who were investigated with semen analysis and serum hormone tests before and 12 months after surgery. Patients were divided into three groups according to their initial sperm concentration; median loss of body mass index was used as a cut-off to further classify patients according to extent of weight loss. Patients' preoperative seminal investigations revealed azoospermia in 13 (28.3%), oligospermia in 19 (41.3%) and normal sperm concentration in 14 (30.4%). Overall, only serum testosterone significantly increased after surgery (P < 0.001). Between study groups, the increase in sperm concentration was statistically significant in men with azoospermia and oligospermia (both P < 0.05), whereas serum testosterone was statistically significant in all groups (P < 0.001). Changes in semen and hormone tests were not affected by the extent of weight loss experienced by patients. Weight loss from bariatric surgery had a favourable effect on serum testosterone levels and semen parameters of patients with pre-existing azoospermia and oligospermia.

Gut Endotoxin Leading to a Decline IN Gonadal function (GELDING) - a novel theory for the development of late onset hypogonadism in obese men

Obesity is an increasing public health problem, with two-thirds of the adult population in many Western countries now being either overweight or obese. Male obesity is associated with late onset hypogonadism, a condition characterised by decreased serum testosterone, sperm quality plus diminished fertility and quality of life. In this paper we propose a novel theory underlying the development of obesity related hypogonadism- the GELDING theory (Gut Endotoxin Leading to a Decline IN Gonadal function). Several observational studies have previously reported an association between obesity related hypogonadism (low testosterone) and systemic inflammation. However, for the first time we postulate that the trans-mucosal passage of bacterial lipopolysaccharide (LPS) from the gut lumen into the circulation is a key inflammatory trigger underlying male hypogonadism. Obesity and a high fat/high calorie diet are both reported to result in changes to gut bacteria and intestinal wall permeability, leading to the passage of bacterial endotoxin (lipopolysaccharide- LPS) from within the gut lumen into the circulation (metabolic endotoxaemia), where it initiates systemic inflammation. Endotoxin is known to reduce testosterone production by the testis, both by direct inhibition of Leydig cell steroidogenic pathways and indirectly by reducing pituitary LH drive, thereby also leading to a decline in sperm production. In this paper we also highlight the novel evolutionary benefits of the GELDING theory. Testosterone is known to be a powerful immune-suppressive, decreasing a man's ability to fight infection. Therefore we postulate that the male reproductive axis has evolved the capacity to lower testosterone production during times of infection and resulting endotoxin exposure, decreasing the immunosuppressive influence of testosterone, in turn enhancing the ability to fight infection. While this response is adaptive in times of sepsis, it becomes maladaptive in the setting of "non-infectious" obesity related metabolic endotoxaemia.

Total testosterone levels are correlated to metabolic syndrome components

INTRODUCTION

Metabolic syndrome (MetS) is a constellation of interrelated risk factors of metabolic origin. Some studies suggest a possible link between low total testosterone (TT) levels and the presence of MetS.

AIM

To analyze the strength and independence of associations between TT and MetS components in non-diabetic men.

METHODS

In this cross-sectional study, 143 non-diabetic men older than 40 were analyzed.

MAIN OUTCOMES MEASURE

Blood samples were collected to evaluate metabolic profile and TT levels. MetS was defined as the presence of three or more of the following characteristics: fasting blood glucose levels ≥ 100 mg/dL, triglyceride ≥ 150 mg/dL, HDL-c < 40 mg/dL, hypertension or blood pressure ≥ 130/85 mmHg, and waist girth > 102 cm.

RESULTS

Mean age of the study population was 61.5 ± 8.61 years old. MetS was present in 47.9% of the individuals. Thirty-four men had low TT and MetS was observed in 23 (70%) against 50 (46%) in those with normal TT (≥ 300 ng/dL) (OR 4.94, p < 0.01), adjusted to confounder's factors. In multiple linear regression analysis, only waist circumference (Beta: -0.395; p = 0.03) and HDL-c (Beta: 0.19; p = 0.04) remained significantly correlated with TT levels.

CONCLUSIONS

Low TT levels were associated with MetS diagnosis. Abdominal obesity was the MetS component independently correlated to low TT levels.