Leptin and androgens in male obesity: evidence for leptin contribution to reduced androgen levels

Long-term follow-up of gonadal dysfunction in morbidly obese adolescent boys after bariatric surgery

Background Elevated body mass index (BMI) is associated with hypogonadism in men but this is not well described in adolescents. The aim is to evaluate gonadal dysfunction and the effects of weight loss after gastric banding in obese adolescent boys. Methods Thirty-seven of 54 boys (age 16.2±1.2 years, mean BMI 48.2 kg/m2) enrolled at the Center for Adolescent Bariatric Surgery at Columbia University Medical Center had low total testosterone for Tanner 5 <350 ng/dL. Sixteen had long-term hormonal data for analysis at baseline (T0), 1 year (T1) and 2 years (T2) post-surgery. T-tests, chi-squared (χ2) tests, correlation and linear mixed models were performed. Results At T0, the hypogonadal group had higher systolic blood pressure (SBP) (75th vs. 57th percentile, p=0.02), fasting insulin (19 vs. 9 μIU/mL, p=0.0008) and homeostatic index of insulin resistance (HOMA-IR) (4.2 vs. 1.9, p=0.009) compared to control group. Total testosterone was negatively correlated with fasting insulin and HOMA-IR. In the long-term analysis, BMI, weight, waist circumference (WC), and % excess weight decreased at T1 and T2 compared to T0. Mean total testosterone at T0, T1 and T2 were 268, 304 and 368 ng/dL, respectively (p=0.07). There was a statistically significant negative correlation between BMI and testosterone after 2 years (r=-0.81, p=0.003). Conclusions Low testosterone levels but unaltered gonadotropins are common in this group and associated with insulin resistance. While a significant increase in testosterone was not found over time, the negative relationship between BMI and testosterone persisted, suggesting there may be an optimal threshold for testosterone production with respect to BMI. Long-term studies are needed.

Insights into leptin signaling and male reproductive health: the missing link between overweight and subfertility?

Obesity stands as one of the greatest healthcare challenges of the 21st century. Obesity in reproductive-age men is ever more frequent and is reaching upsetting levels. At the same time, fertility has taken an inverse direction and is decreasing, leading to an increased demand for fertility treatments. In half of infertile couples, there is a male factor alone or combined with a female factor. Furthermore, male fertility parameters such as sperm count and concentration went on a downward spiral during the last few decades and are now approaching the minimum levels established to achieve successful fertilization. Hence, the hypothesis that obesity and deleterious effects in male reproductive health, as reflected in deterioration of sperm parameters, are somehow related is tempting. Most often, overweight and obese individuals present leptin levels directly proportional to the increased fat mass. Leptin, besides the well-described central hypothalamic effects, also acts in several peripheral organs, including the testes, thus highlighting a possible regulatory role in male reproductive function. In the last years, research focusing on leptin effects in male reproductive function has unveiled additional roles and molecular mechanisms of action for this hormone at the testicular level. Herein, we summarize the novel molecular signals linking metabolism and male reproductive function with a focus on leptin signaling, mitochondria and relevant pathways for the nutritional support of spermatogenesis.

Testosterone Levels and Type 2 Diabetes-No Correlation with Age, Differential Predictive Value in Men and Women

Most studies reporting on the association of circulating testosterone levels with type 2 diabetes in men are of cross-sectional design. Reports on the relevance of altered testosterone levels in women are scarce. Here, we evaluate the role of low serum testosterone levels for incident diabetes in men and women in a population setting of 7706 subjects (3896 females). During a mean follow up time of 13.8 years, 7.8% developed type 2 diabetes. Significant correlations of testosterone with high density lipoprotein (HDL)-cholesterol (R = 0.21, p < 0.001), body-mass-index (R = −0.23, p < 0.001), and waist-to-hip-ratio (R = −0.21, p < 0.001) were found in men. No correlation was found with age in men; in women, the correlation was negligible (R = 0.04, p = 0.012). In men, low testosterone levels predicted high risk of type 2 diabetes, while in women this relationship was opposite. Men with low testosterone levels showed increased risk of future diabetes (hazard ratio (HR) 2.66, 95% confidence interval (CI) 1.91–3.72, p < 0.001 in basic model; HR 1.56 95%, CI 1.10–2.21, p = 0.003). In women, low testosterone levels indicated lower risk with (HR 0.53, 95% CI 0.37–0.77, p = 0.003), while the association lost significance in the fully adjusted model (HR 0.72, 95% CI 0.49–1.05, p = 0.09). Low levels of testosterone predicted future diabetes in men. A borderline opposite association was found in women.

Obesity and Erectile Dysfunction: From Bench to Clinical Implication

Obesity is a major public health issue worldwide and is frequently associated with erectile dysfunction (ED). Both conditions may share an internal pathologic environment, also known as common soil. Their main pathophysiologic processes are oxidative stress, inflammation, and resultant insulin and leptin resistance. Moreover, the severity of ED is correlated with comorbid medical conditions, including obesity. Therefore, amelioration of these comorbidities may increase the efficacy of ED treatment with phosphodiesterase 5 inhibitors, the first-line medication for patients with ED. Although metformin was originally developed as an insulin sensitizer six decades ago, it has also been shown to improve leptin resistance. In addition, metformin has been reported to reduce oxidative stress, inflammatory response, and body weight, as well as improve ED, in animal and human studies. Moreover, administration of a combination of metformin and phosphodiesterase 5 inhibitors improves erectile function in patients with ED who have a poor response to sildenafil and are insulin resistant. Thus, concomitant treatment of metabolic derangements associated with obesity in patients with ED who are obese would improve the efficacy and reduce the refractory response to penile vasodilators. In this review, we discuss the connecting factors between obesity and ED and the possible combined treatment modalities.

Insulin Sensitivity and Testicular Function in a Cohort of Adult Males Suspected of Being Insulin-Resistant

A cohort of 141 males (18–80 yo, 42.9 ± 12.9) strongly suspected of being Insulin Resistant (IR) was prospectively studied by determining their insulin sensitivity (Pancreatic Suppression Test, PST) and testicular function (total testosterone and SHBG). The subjects were labeled as IR when the Steady State Plasma Glucose (SSPG) was ≥150 mg/dL and Non-Insulin Resistant (NIR) when SSPG was <150 mg/dl; similarly, the subjects were labeled as Hypogonadal (HYPOG) when total testosterone was ≤3.0 ng/mL and Eugonadal (EUG) when total testosterone was >3.0 ng/mL. Two out of three subjects turned out to be IR, while around one in four subjects were HYPOG. Contingency analysis indicated a significant interdependence between insulin resistance and hypogonadism (chi-square was 4.69, p = 0.0303). Age (>43 yo) predicted hypogonadism (AUROC 0.606, p = 0.0308). Twice as many HYPOG subjects were IR as compared with EUG subjects. Also, HYPOG subjects exhibited higher SSPG values as compared with EUG subjects. Statistically, neither Weight nor BMI predicted hypogonadism, while Waist Circumference (>110 cm) was only a mediocre predictor (AUROC 0.640, p = 0.009). SSPG (>224 mg/dL) on the other hand, was the best predictor of hypogonadism (AUROC 0.709, p = 0.002), outperforming Waist Circumference (half of the subjects with an SSPG >224 mg/dL were HYPOG). Age did not predict insulin resistance, while Weight (>99 kg), BMI (>29), and especially, Waist Circumference (>99 cm, AUROC 0.812, p < 0.0001) were all predictors of insulin resistance. Almost 90% of the subjects with a waist circumference >99 cm was IR. As a logical consequence of the selection criteria (various clues suggesting insulin resistance), most subjects with normal weight in this cohort were IR (53.3%) while 20% were HYPOG. On the other hand, 13.6% of the obese subjects were NIR, and 2 out of 3 of them were both NIR and EUG. In conclusion, Waist Circumference predicted both insulin resistance (>99 cm) and hypogonadism (>110 cm), suggesting that the first hit of abdominal obesity is insulin resistance and the second hit is male hypogonadism. Normal weight did not protect from IR, while a relevant proportion of obese subjects were NIR (with 2/3 being also EUG).

Cross-Sectional Inverse Associations of Obesity and Fat Accumulation Indicators with Testosterone in Non-Diabetic Aging Men

Introduction/Objective: The aim of the study was to show which of the adipose tissue accumulation indicators correlate with testosterone disorders in non-diabetic aging men. Material and methods: 455 non diabetic men, recruited at primary care facilities, aged 50⁻75 participated in the study. The participants underwent anthropometric measurement and ELISA determination of total testosterone (TT), estradiol (E₂), dehydroepiandrosterone sulphate (DHEA-S), sex hormone binding protein (SHBG), and the determination of fasting glucose (FPG), high-density lipids cholesterol (HDL-Ch), and triacylglycerols (TAG) in serum. The following indicators were calculated: body mass index (BMI), waist-to-hip ratio (WHR), lipid accumulation product (LAP), and visceral adiposity index (VAI). Results: Men with testosterone deficiency syndrome (TDS) differed in each of the assessed obesity indices from those without TDS. All of the studied parameters correlated significantly negatively with TT concentration in blood serum, with VAI being the strongest predictor of TDS. It was shown that the threshold value at which the risk of TDS increased was 28.41 kg/m² for BMI, 1.58 for VAI, 104 cm for WC, and 37.01 for LAP. Conclusions: Indicators of fat accumulation that take into account biochemical parameters in assessing lipid metabolism are better markers of actual body fat deposition than indicators based solely on anthropometric measurements. Among them, VAI seems the most suitable biomarker of TDS in non-diabetic aging men.

Di-(2-Ethylhexyl) Phthalate Increases Obesity-Induced Damage to the Male Reproductive System in Mice

OBJECTIVE

This study evaluated the effects of di-(2-ethylhexyl) phthalate (DEHP) and obesity on male reproductive organ function in male mice and the potential mechanism of male secondary hypogonadism (SH) in such mice.

METHODS

140 mice were assigned to six groups for 12 weeks: normal, DEHP, DIO, DIO + DEHP low, DIO + DEHP middle, and DIO + DEHP high. The effects of DEHP and obesity upon the reproductive organs were determined by measuring sperm count and motility, relative testis and epididymis weight, hormone level, and pathological changes. Oxidative stress was evaluated by determining malondialdehyde, T-AOC, SOD, GSH, H2O2, CAT, and GSH-PX in testicular tissues. Nrf2 and Keap1 protein were measured by Western blotting.

RESULTS

DEHP and obesity reduced sperm count and motility, relative testis and epididymis weight, and testosterone level but increased the levels of MDA, H2O2, leptin, and estradiol. Pathological injury was observed in the testicular Leydig cells. Moreover, the activity of CAT, SOD, and GSH-Px enzymes was inhibited. Nrf2 protein expression was reduced but that of Keap1 was increased.

CONCLUSIONS

DEHP and obesity jointly caused damage to male productive function. Oxidative stress in testicular tissue, and a high level of leptin, may provide some evidence to clarify the mechanisms of male SH with DEHP and obesity.

The in vitro modulation of steroidogenesis by inflammatory cytokines and insulin in TM3 Leydig cells

BACKGROUND

Cytokines and hormones, including insulin, are known to modulate the hypothalamic-pituitary-testes axis and steroidogenesis, both centrally and peripherally. In the context of chronic inflammation and hyperinsulinaemia mediating male hypogonadism associated with obesity, metabolic syndrome and type 2 diabetes mellitus, these mechanisms are poorly understood and the impact of cytokines and insulin on Leydig cell steroidogenesis has not been fully elicited. This study aimed to further investigate the in vitro impact of TNFα, IL1ß, IL6, IL8 and insulin on Leydig cell function and steroidogenesis.

METHODS

hCG-stimulated TM3 Leydig cells were exposed to various concentrations of TNFα, IL1ß, IL6, IL8 (100 ng/ml, 10 ng/ml, 1 ng/ml and 0.1 ng/ml) and insulin (10 ng/ml, 1 ng/ml, 0.1 ng/ml and 0.01 ng/ml) in optimal cell culture conditions over 48 h. Cell viability (XTT) and testosterone and progesterone concentrations (ELISA) were assessed using standardised laboratory techniques.

RESULTS

TNFα significantly decreased cell viability and progesterone and testosterone concentrations in a dose-dependent relationship. IL1ß and IL6 had a subtle but significant negative effect on cell viability and testosterone concentrations, with a marked significant decrease in progesterone concentration at all concentrations investigated. IL8 showed an increase in cell viability, with no significant effect on testosterone concentrations alongside a significant decrease in progesterone concentrations. Insulin significantly increased cell viability and testosterone concentrations in a dose dependent relationship, but interestingly significantly decreased progesterone concentrations.

CONCLUSIONS

The inflammatory cytokines TNFα, IL1β and IL6 cause a dose dependent decline in steroidogenesis in TM3 Leydig cells. These results suggest that chronic inflammation may downregulate steroidogenesis in males via direct modulation of Leydig cell function. However, IL8 may stimulate TM3 Leydig cell growth. Insulin is associated with a dose-dependent increase in testosterone synthesis, with a significant decline in progesterone synthesis. With the phenomenon of insulin resistance, the literature is unclear on the potential role of hyperinsulinaemia in steroidogenesis. Further studies are warranted in order to fully elicit the molecular mechanisms and interactions of these molecules on male steroidogenesis.

Obesity, An Enemy of Male Fertility: A Mini Review

Obesity is a highly prevalent non-communicable disease worldwide and is commonly associated with male infertility. Several etiopathological theories have been mentioned in the literature by which obesity affects spermatogenesis, thus affecting the male fertility potential. Mechanisms for explaining the effect of obesity on male infertility include endocrinopathy, increased aromatization activity, associated erectile dysfunction, psychological and thermal effects, obstructive sleep apnea, increased leptin and oxygen free radicals, and associated inflammatory and obstructive elements of epididymitis. Treatment of such a complex problem includes weight reduction (by lifestyle modification and increased physical activity), optimization of altered testosterone-to-estradiol ratio using aromatase inhibitors and/or gonadotropins, treatment of associated comorbidities by phosphodiesterase inhibitors for erectile dysfunction, and insulin-sensitizing agents for the management of diabetes. The aim of this mini-review is to highlight the pathological basis of this problem and to focus on obesity as an etiology of male infertility.

Chicken Is a Useful Model to Investigate the Role of Adipokines in Metabolic and Reproductive Diseases

Reproduction is a complex and essential physiological process required by all species to produce a new generation. This process involves strict hormonal regulation, depending on a connection between the hypothalamus-pituitary-gonadal axis and peripheral organs. Metabolic homeostasis influences the reproductive functions, and its alteration leads to disturbances in the reproductive functions of humans as well as animals. For a long time, adipose tissue has been recognised as an endocrine organ but its ability to secrete and release hormones called adipokines is now emerging. Adipokines have been found to play a major role in the regulation of metabolic and reproductive processes at both central and peripheral levels. Leptin was initially the first adipokine that has been described to be the most involved in the metabolism/reproduction interrelation in mammals. In avian species, the role of leptin is still under debate. Recently, three novel adipokines have been discovered: adiponectin (ADIPOQ, ACRP30), visfatin (NAMPT, PBEF), and chemerin (RARRES2, TIG2). However, their mode of action between mammalian and nonmammalian species is different due to the different reproductive and metabolic systems. Herein, we will provide an overview of the structure and function related to metabolic and reproductive mechanisms of the latter three adipokines with emphasis on avian species.

Androgens and Hypertension in Men and Women: a Unifying View

PURPOSE OF REVIEW

This review was designed to revaluate the androgen role on the mechanisms of hypertension and cardiovascular risks in both men and women. Sex steroids are involved in the regulation of blood pressure, but pathophysiological mechanism is not well understood. Androgens have an important effect on metabolism, adipose and endothelial cell function, and cardiovascular risk in both men and women. A focal point in this contest is represented by the possible gender-specific regulation of different tissues and in particular of the adipose cell. Available data confirm that androgen deficiency is linked to increased prevalence of hypertension and cardiovascular diseases. Adipocyte dysfunction seems to be the main involved mechanism. Androgen replacement reduces inflammation state in man, protecting by metabolic syndrome progression. In women, androgen excess has been considered as promoting factor of cardiovascular risk. However, recent data suggest that excessive androgen production has little effect per se in inducing hypertension in young women of reproductive age. Also in postmenopausal women, data on relative androgen excess and hypertension are missing, while adrenal androgen deficiency has been associated to increased mortality.

RECENT FINDINGS

Molecular mechanisms linking androgen dysregulation to hypertension are almost Unknown, but they seem to be related to increased visceral fat, promoting a chronic inflammatory state through different mechanisms. One of these may involve the recruitment and over-activation of NF-kB, a ubiquitous transcription factor also expressed in adipose cells, where it may cause the production of cytokines and other immune factors. The NF-kB signalling pathway may also influence brown adipogenesis leading to the preferential enlargement of visceral adipocytes. Chronic inflammation and adipocyte dysfunction may alter endothelial function leading to hypertension. Both in men and in women, particularly in the post-menopausal period, hypoandrogenism seems to be a major determinant of the increased prevalence of hypertension. The relationship between androgen signalling and NF-kB might explain the pathophysiological mechanism leading to the development of endothelium dysfunction and hypertension.

MECHANISMS IN ENDOCRINOLOGY: The sexually dimorphic role of androgens in human metabolic disease

Female androgen excess and male androgen deficiency manifest with an overlapping adverse metabolic phenotype, including abdominal obesity, insulin resistance, type 2 diabetes mellitus, non-alcoholic fatty liver disease and an increased risk of cardiovascular disease. Here, we review the impact of androgens on metabolic target tissues in an attempt to unravel the complex mechanistic links with metabolic dysfunction; we also evaluate clinical studies examining the associations between metabolic disease and disorders of androgen metabolism in men and women. We conceptualise that an equilibrium between androgen effects on adipose tissue and skeletal muscle underpins the metabolic phenotype observed in female androgen excess and male androgen deficiency. Androgens induce adipose tissue dysfunction, with effects on lipid metabolism, insulin resistance and fat mass expansion, while anabolic effects on skeletal muscle may confer metabolic benefits. We hypothesise that serum androgen concentrations observed in female androgen excess and male hypogonadism are metabolically disadvantageous, promoting adipose and liver lipid accumulation, central fat mass expansion and insulin resistance.

Steroidogenic genes expressions are repressed by high levels of leptin and the JAK/STAT signaling pathway in MA-10 Leydig cells

The adipose tissue is an important endocrine organ secreting numerous peptide hormones, including leptin. Increased circulating levels of leptin, as a result of hormonal resistance in obese individuals, may contribute to lower androgen production in obese males. However, the molecular mechanisms involved need to be better defined. Androgens are mainly produced by Leydig cells within the testis. In male rodents, activation of the leptin receptor modulates a cascade of intracellular signal transduction pathways which may lead to regulation of transcription factors having influences on steroidogenesis in Leydig cells. Thus, as a result of high leptin levels interacting with its receptor and modulating the activity of the JAK/STAT signaling pathway, the activity of transcription factors important for steroidogenic genes expressions may be inhibited in Leydig cells. Here we show that Lepr is increasingly expressed within Leydig cells according to postnatal development. Although high levels of leptin (corresponding to obesity condition) alone had no effect on Leydig cells' steroidogenic genes expression, it downregulated cAMP-dependent activations of the cholesterol transporter Star and of the rate-limiting steroidogenic enzyme Cyp11a1. Our results suggest that STAT transcriptional activity is downregulated by high levels of leptin, leading to reduced cAMP-dependent steroidogenic genes (Star and Cyp11a1) expressions in MA-10 Leydig cells. However, other transcription factors such as members of the SMAD and NFAT families may be involved and need further investigation to better define how leptin regulates their activities and their relevance for Leydig cells function.

Metabolic endotoxaemia related inflammation is associated with hypogonadism in overweight men

BACKGROUND

Obesity is associated with both impaired testosterone production and a chronic state of low grade inflammation. Previously it was believed that this inflammation was mediated by a decline in the immunosuppressive action of testosterone. However, more recently an alternative hypothesis (GELDING theory) has suggested that inflammation originating from the passage of intestinal bacteria into the circulation (metabolic endotoxaemia) may actually be the cause of impaired testicular function in obese men. The aim of this study is to investigate if metabolic endotoxaemia, as quantified by serum Lipopolysaccharide Binding Protein (LBP), is associated with impaired testicular endocrine function.

METHODS

A total of 50 men aged between 21 and 50 years (mean 35.1 ± 6.8 years) were assessed for adiposity (BMI, waist circumference and % body fat using bio-impedance), inflammatory status (serum CRP, IL-1β, IL-6, TNFα and LBP) and testicular endocrine function (serum testosterone, estradiol, AMH, LH and FSH). Statistical analysis was performed using Pearson correlation analysis, with log transformation of data where appropriate, and multi-variate regression.

RESULTS

Overall increasing adiposity (% body fat) was positively associated with metabolic endotoxaemia (LBP, r = 0.366, p = 0.009) and inflammation (CRP r = 0.531, p < 0.001; IL-6 r = 0.463, p = 0.001), while also being negatively correlated with serum testosterone (r = -0.403, p = 0.004). Serum testosterone levels were significantly negatively correlated with inflammation (CRP r = -0.471, p = 0.001; IL-6 r = -0.516, p < 0.001) and endotoxaemia (LBP) after adjusting for serum LH levels (p = -0.317, p = 0.03). Furthermore, serum IL-6 was negatively associated with AMH levels (r = -0.324, p = 0.023), with a negative trend between LBP and AMH also approaching significance (r = -0.267, p = 0.064).

CONCLUSIONS

Obesity and its associated metabolic endotoxaemia helps initiate a pro-inflammatory state characterised by raised serum IL-6 levels, which in turn is correlated with impairment of both Leydig (testosterone) and Sertoli cell function (AMH). These results open up the potential for new treatments of obesity related male hypogonadism that focus on preventing the endotoxaemia associated chronic inflammatory state.

Effect of Testosterone Treatment on Adipokines and Gut Hormones in Obese Men on a Hypocaloric Diet

Context

In obese men with lowered testosterone levels, testosterone treatment augments diet-associated loss of body fat.

Objective

We hypothesized that testosterone treatment modulates circulating concentrations of hormonal mediators of fat mass and energy homeostasis in obese men undergoing a weight loss program.

Design

Prespecified secondary analysis of a randomized, double-blind, placebo-controlled trial.

Setting

Tertiary referral center.

Participants

Obese men (body mass index ≥30 kg/m²) with a repeated total testosterone level ≤12 nmol/L.

Intervention

One hundred participants mean age 53 years (interquartile range 47 to 60 years) receiving 10 weeks of a very low-energy diet followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of intramuscular testosterone undecanoate (cases, n = 49) or matching placebo (controls, n = 51). Eighty-two men completed the study.

Main outcomes

Between-group differences in leptin, adiponectin, ghrelin, glucagon like peptide-1, gastric inhibitory polypeptide, peptide YY, pancreatic polypeptide, and amylin levels.

Results

At study end, compared with controls, cases had greater reductions in leptin [mean adjusted difference (MAD), -3.6 ng/mL (95% CI, -5.3 to -1.9); P < 0.001]. The change in leptin levels between cases and controls was dependent on baseline fat mass, as the between-group difference progressively increased with increasing fat mass [MAD, -0.26 ng/mL (95% CI, -0.31 to -0.26); P = 0.001 per 1 kg of baseline fat mass]. Weight loss-associated changes in other hormones persisted during the weight maintenance phase but were not modified by testosterone treatment.

Conclusions

Testosterone treatment led to reductions in leptin beyond those achieved by diet-associated weight loss. Testosterone treatment may reduce leptin resistance in obese men.

The Association between Exposure to Environmental Bisphenol A and Gonadotropic Hormone Levels among Men

Bisphenol A (BPA) is an extensively used chemical with endocrine disrupting properties. Although animal and in vivo studies have suggested possible effects of BPA on levels of gonadotropic hormones, human studies are limited and inconclusive. The study examined whether environmental BPA exposure was associated with gonadotropic hormones levels in men. A total of 560 men aged 18–55 years were recruited from Sandu County, Guizhou Province, China. We collected urine samples for measurement of BPA, and blood samples for measurement of reproductive hormones. We examined serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and total testosterone (T). Relative risk (RR) was obtained by log-binominal regression to explore the association between urinary BPA level and hormone levels. BPA was detected in 70.4% of urine samples, with a geometric mean of 0.50 μg/gCr. Men with detectable levels of BPA had a 1.52-fold increased risk of having a high LH level (>75^th percentile) when compared with men with undetectable levels of BPA, after adjustment for potential confounders (95% confidence interval (CI): 1.04–2.21). The association persisted and slightly intensified among current smokers (adjusted RR (aRR) = 1.76, 95%CI: 1.05–2.95), while it weakened among non-smokers (aRR = 1.17, 95%CI: 0.69–1.96). Urinary BPA level was associated with an increased FSH level among smokers (aRR = 1.64, 95%CI: 1.01–2.67). Urinary BPA level was inversely associated with total T level among males with body max index (BMI) ≥25 kg/m² although this association was of borderline significance (aRR = 0.52, 95%CI: 0.26–1.05). In conclusion, environmental exposure to BPA was associated with increased serum levels of LH and FSH in male smokers, along with decreased serum levels of total T in men with BMI≥25 kg/m². These findings suggest that the effects of environmental BPA exposure on hormone levels might be modified by smoking and BMI.

Transcriptional Profile of Kidney from Type 2 Diabetic db/db Mice

Diabetic nephropathy (DN), a common diabetic microvascular complication, is characterized by progressive glomerular sclerosis and tubulointerstitial fibrosis. However, the underlying mechanisms involved in DN remain to be elucidated. We explored changes in the transcriptional profile in spontaneous type 2 diabetic db/db mice by using the cDNA microarray. Compared with control db/m mice, the db/db mice exhibited marked increases in body weight, kidney weight, and urinary albumin excretion. Renal histological analysis revealed mesangial expansion and thickness of the basement membrane in the kidney of the db/db mice. A total of 355 differentially expressed genes (DEGs) were identified by microarray analysis. Pathway enrichment analysis suggested that biological oxidation, bile acid metabolism, and steroid hormone synthesis were the 3 major significant pathways. The top 10 hub genes were selected from the constructed PPI network of DEGs, including Ccnb2 and Nr1i2, which remained largely unclear in DN. We believe that our study can help elucidate the molecular mechanisms underlying DN.

Curcumin ameliorates high‑fat diet‑induced spermatogenesis dysfunction

Curcumin, a type of natural active ingredient, is derived from rhizoma of Curcuma, which possesses antioxidant, antitumorigenic and anti-inflammatory activities. The present study aimed to investigate whether treatment with curcumin reduced high-fat diet (HFD)-induced spermatogenesis dysfunction. Sprague-Dawley rats fed a HFD were treated with or without curcumin for 8 weeks. The testis/body weight, histological analysis and serum hormone levels were used to evaluate the effects of curcumin treatment on spermatogenesis dysfunction induced by the HFD. In addition, the expression levels of apoptosis associated proteins, Fas, B-cell lymphoma (Bcl)-xl, Bcl-associated X protein (Bax) and cleaved-caspase 3, were determined in the testis. The results of the present study suggested that curcumin treatment attenuated decreased testis/body weight and abnormal hormone levels. Morphological changes induced by a HFD were characterized as atrophied seminiferous tubules, decreased spermatogenetic cells and interstitial cells were improved by curcumin treatment. In addition, curcumin treatment reduced apoptosis in the testis, and decreased expression of Fas, Bax and cleaved-caspase 3, as well as increased expression of Bcl-xl. In conclusion, the present study revealed that curcumin treatment reduced HFD-induced spermatogenesis dysfunction in male rats.

Obesity, Oxidative Stress, Adipose Tissue Dysfunction, and the Associated Health Risks: Causes and Therapeutic Strategies

Obesity is gaining acceptance as a serious primary health burden that impairs the quality of life because of its associated complications, including diabetes, cardiovascular diseases, cancer, asthma, sleep disorders, hepatic dysfunction, renal dysfunction, and infertility. It is a complex metabolic disorder with a multifactorial origin. Growing evidence suggests that oxidative stress plays a role as the critical factor linking obesity with its associated complications. Obesity per se can induce systemic oxidative stress through various biochemical mechanisms, such as superoxide generation from NADPH oxidases, oxidative phosphorylation, glyceraldehyde auto-oxidation, protein kinase C activation, and polyol and hexosamine pathways. Other factors that also contribute to oxidative stress in obesity include hyperleptinemia, low antioxidant defense, chronic inflammation, and postprandial reactive oxygen species generation. In addition, recent studies suggest that adipose tissue plays a critical role in regulating the pathophysiological mechanisms of obesity and its related co-morbidities. To establish an adequate platform for the prevention of obesity and its associated health risks, understanding the factors that contribute to the cause of obesity is necessary. The most current list of obesity determinants includes genetic factors, dietary intake, physical activity, environmental and socioeconomic factors, eating disorders, and societal influences. On the basis of the currently identified predominant determinants of obesity, a broad range of strategies have been recommended to reduce the prevalence of obesity, such as regular physical activity, ad libitum food intake limiting to certain micronutrients, increased dietary intake of fruits and vegetables, and meal replacements. This review aims to highlight recent findings regarding the role of oxidative stress in the pathogenesis of obesity and its associated risk factors, the role of dysfunctional adipose tissue in development of these risk factors, and potential strategies to regulate body weight loss/gain for better health benefits.

Importance of Different Grades of Abdominal Obesity on Testosterone Level, Erectile Dysfunction, and Clinical Coincidence

The aim of the current study was to investigate the influence of different grades of abdominal obesity (AO) on the prevalence of testosterone deficiency syndrome (TDS), erectile dysfunction (ED), and metabolic syndrome (MetS). In a cross-sectional descriptive study, a total of 216 males underwent a complete urological, internal, and hormonal evaluation. Males were divided according to waist circumference into five groups: less than 94 cm (Grade [G] 0), 94 to 101 cm (G1), 102 to 109 cm (G2), 110 to 119 cm (G3), and more than 120 cm (G4). Incidence of ED, TDS, and MetS was compared in these groups and in participants without AO. Some degree of ED was identified in 74.7% of males with AO. In G1, there were 61% of males with ED, in G2 68%, in G3 83%, and in G4 87%. A strong correlation between testosterone (TST) level and AO was identified. Ninety-eight out of 198 (49.5%) males with AO and 1/18 (5.5%) males without AO had TDS. There were significant differences between individual groups. In the group of males with AO G4 (more than 120 cm), 87.1% had TDS. MetS was diagnosed in 105/198 (53.0%) males with AO, but in G4, 83.9% of males with AO had MetS. Males older than 40 years of age with AO have a higher incidence of ED, TDS, and MetS. Dividing males into five groups according to waist circumference seems to be reasonable. With growing AO, there were significantly more males with ED, TDS, and MetS.

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.

Current medical management of endocrine-related male infertility

Male factor contributes to 50%-60% of overall infertility but is solely responsible in only 20% of couples. Although most male factor infertility is ascertained from an abnormal semen analysis, other male factors can be contributory especially if the sample returns normal. Male infertility can be due to identifiable hormonal or anatomical etiologies that may be reversible or irreversible. This manuscript will highlight existing guidelines and our recommendations for hormone evaluation for male infertility and empiric therapies including multivitamins, estrogen receptor modulators (clomiphene), estrogen conversion blockers (anastrozole), and hormone replacement.

Clinical management of infertile men with nonobstructive azoospermia

The clinical management of men with nonobstructive azoospermia (NOA) seeking fertility has been a challenge for andrologists, urologists, and reproductive medicine specialists alike. This review presents a personal perspective on the clinical management of NOA, including the lessons learned over 15 years dealing with this male infertility condition. A five-consecutive-step algorithm is proposed to manage such patients. First, a differential diagnosis of azoospermia is made to confirm/establish that NOA is due to spermatogenic failure. Second, genetic testing is carried out not only to detect the males in whom NOA is caused by microdeletions of the long arm of the Y chromosome, but also to counsel the affected patients about their chances of having success in sperm retrieval. Third, it is determined whether any intervention prior to a surgical retrieval attempt may be used to increase sperm production. Fourth, the most effective and efficient retrieval method is selected to search for testicular sperm. Lastly, state-of-art laboratory techniques are applied in the handling of retrieved gametes and cultivating the embryos resulting from sperm injections. A coordinated multidisciplinary effort is key to offer the best possible chance of achieving a biological offspring to males with NOA.

Testosterone deficiency in the aging male

Treatment for hypogonadism is on the rise, particularly in the aging population. Yet treatment in this population represents a unique challenge to clinicians. The physiology of normal aging is complex and often shares the same, often vague, symptoms of hypogonadism. In older men, a highly prevalent burden of comorbid medical conditions and polypharmacy complicates the differentiation of signs and symptoms of hypogonadism from those of normal aging, yet this differentiation is essential to the diagnosis of hypogonadism. Even in older patients with unequivocally symptomatic hypogonadism, the clinician must navigate the potential benefits and risks of treatment that are not clearly defined in older men. More recently, a greater awareness of the potential risks associated with treatment in older men, particularly in regard to cardiovascular risk and mortality, have been appreciated with recent changes in the US Food and Drug Administration recommendations for use of testosterone in aging men. The aim of this review is to provide a framework for the clinician evaluating testosterone deficiency in older men in order to identify correctly and treat clinically significant hypogonadism in this unique population while minimizing treatment-associated harm.

Effect of Myoinositol and Antioxidants on Sperm Quality in Men with Metabolic Syndrome

This prospective longitudinal study investigated the effects of a dietary supplement in patients affected by reduced sperm motility (asthenospermic males) with metabolic syndrome. The product tested was Andrositol®, which contains myoinositol (MI) as principal compound, in association with other molecules, and the parameters evaluated were semen characteristics as well as hormone and metabolic profiles. The inclusion criteria were subjects aged over 18 years, with asthenospermia and metabolic syndrome. The exclusion criteria were presence of cryptorchidism, varicocele, and prostatitis. For this study, 45 males who had such features were enrolled. Their selection was made according to the 2010 World Health Organization (WHO) criteria (5th Edition) for the Evaluation of Human Semen. Hormone and metabolic profiles and semen parameters were assessed at the beginning of the study and after three months of treatment with Andrositol. The differences between the values before and after the supplementation were found statistically significant. Andrositol normalized the metabolic profile of these patients, improving their insulin sensitivity. Moreover, testosterone levels were increased and the semen characteristics, such as sperm concentration, motility, and morphology, highly improved. In conclusion, the association of MI with other molecules (micronutrients and vitamins) could be an effective therapy for metabolic disorders, as well as hormonal and spermatic changes responsible for male infertility.

Changes in Testosterone Levels and Sex Hormone-Binding Globulin Levels in Extremely Obese Men after Bariatric Surgery

Objective. Obesity is a risk factor for hypogonadotropic hypogonadism in men. Weight loss has been shown to improve hypogonadism in obese men. This study evaluated the early changes in sex hormones profile after bariatric surgery. Methods. This is a prospective study including 29 morbidly obese men. Main outcomes were changes in serum levels of total testosterone (TT), free testosterone (cFT), SHBG, estradiol, adiponectin, and leptin at 1 and 6 months after surgery. Results. The mean age of patients was 31 ± 8 years and the mean BMI was 56.8 ± 11.7 kg/m². Fifteen patients underwent Roux-en-Y gastric bypass and 14 patients underwent sleeve gastrectomy. At baseline, 22 patients (75.9%) had either low TT levels (<10.4 nmol/L) or low cFT levels (<225 pmol/L). Total testosterone and SHBG levels increased significantly at 1 month after surgery (p ≤ 0.001). At 6 months after surgery, TT and cFT increased significantly (p ≤ 0.001) and 22 patients (75.9%) had normalized TT and cFT levels. There were no changes in estradiol levels at either 1 month or 6 months after surgery. Conclusions. Increases in TT and SHBG levels occurred early at 1 month after bariatric surgery while improvements in cFT levels were observed at 6 months after bariatric surgery.

Diagnosis and management of testosterone deficiency

Testosterone supplementation therapy (TST) use has dramatically increased over the past decade, due to the availability of newer agents, aggressive marketing, and an increasing incidence of testosterone deficiency (TD). Despite the increase in TST, a degree of ambiguity remains as to the exact diagnostic criteria of TD, and administration and monitoring of TST. One explanation for this phenomenon is the complex role testosterone plays in multiple physiologic pathways. Numerous medical co-morbidities and medications can alter testosterone levels resulting in a wide range of nonspecific clinical signs and symptoms of TD. The diagnosis is also challenging due to the lack of a definitive serum total testosterone level that reliably correlates with symptoms. This observation is particularly true in the aging male and is exacerbated by inconsistencies between different laboratory assays. Several prominent medical societies have developed guideline statements to clarify the diagnosis, but they differ from each other and with expert opinion in several ways. Aside from diagnostic dilemmas, there are numerous subtle advantages and disadvantages of the various testosterone agents to appreciate. The available TST agents have changed significantly over the past decade similar to the trends in the diagnosis of TD. Therefore, as the usage of TST increases, clinicians will be challenged to maintain an up-to-date understanding of TD and TST. The purpose of this review is to provide a clear description of the current strategies for diagnosis and management of TD.

Ameliorative Effect of Zinc Oxide Nanoparticles on Antioxidants and Sperm Characteristics in Streptozotocin-Induced Diabetic Rat Testes

The present study investigated the impact of zinc oxide nanoparticles (ZnONPs) on the oxidative status and sperm characteristics in diabetic rat testicular tissue. Forty male albino rats were used in this study; 10 of them served as a control and 30 rats were injected with a single dose (100 mg/kg) of streptozotocin intraperitoneally. They were subdivided into diabetic, diabetic + ZnONPs (10 mg/kg B.W.), and diabetic and cotreated with ZnONPs + insulin groups. The sperm count and motility were assessed. The activity and mRNA expression of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GRD), and Glutathion-S-Transferase (GST) were determined in the testicular tissue. Malondialdehyde (MDA) and reduced glutathione (GSH) levels were estimated in the testicular tissue. Sperm count and motility increased in ZnONPs treated diabetic rats. A significant increase in the activity and mRNA expression of SOD, CAT, GPx, GRD, and GST was shown in ZnONPs treated diabetic rats. MDA significantly decreased, while GSH increased in testicular tissue of ZnONPs treated diabetic rats. It was concluded that ZnONPs either alone or in combination with insulin have the ability to increase the sperm count and motility and protect the testicular tissue against the oxidative stress induced by diabetes in rats.

Impact of Diet-Induced Obesity and Testosterone Deficiency on the Cardiovascular System: A Novel Rodent Model Representative of Males with Testosterone-Deficient Metabolic Syndrome (TDMetS)

INTRODUCTION

Current models of obesity utilise normogonadic animals and neglect the strong relationships between obesity-associated metabolic syndrome (MetS) and male testosterone deficiency (TD). The joint presentation of these conditions has complex implications for the cardiovascular system that are not well understood. We have characterised and investigated three models in male rats: one of diet-induced obesity with the MetS; a second using orchiectomised rats mimicking TD; and a third combining MetS with TD which we propose is representative of males with testosterone deficiency and the metabolic syndrome (TDMetS).

METHODS

Male Wistar rats (n = 24) were randomly assigned to two groups and provided ad libitum access to normal rat chow (CTRL) or a high fat/high sugar/low protein "obesogenic" diet (OGD) for 28 weeks (n = 12/group). These groups were further sub-divided into sham-operated or orchiectomised (ORX) animals to mimic hypogonadism, with and without diet-induced obesity (n = 6/group). Serum lipids, glucose, insulin and sex hormone concentrations were determined. Body composition, cardiovascular structure and function; and myocardial tolerance to ischemia-reperfusion were assessed.

RESULTS

OGD-fed animals had 72% greater fat mass; 2.4-fold greater serum cholesterol; 2.3-fold greater serum triglycerides and 3-fold greater fasting glucose (indicative of diabetes mellitus) compared to CTRLs (all p<0.05). The ORX animals had reduced serum testosterone and left ventricle mass (p<0.05). In addition to the combined differences observed in each of the isolated models, the OGD, ORX and OGD+ORX models each had greater CK-MB levels following in vivo cardiac ischemia-reperfusion insult compared to CTRLs (p<0.05).

CONCLUSION

Our findings provide evidence to support that the MetS and TD independently impair myocardial tolerance to ischemia-reperfusion. The combined OGD+ORX phenotype described in this study is a novel animal model with associated cardiovascular risk factors and complex myocardial pathology which may be representative of male patients presenting with TDMetS.

Determinants of testosterone levels in human male obesity

Testosterone (T) levels are decreased in obese men, but the underlying causes are incompletely understood. Our objective was to explore the relation between low (free) T levels and male obesity, by evaluating metabolic parameters, subcutaneous adipose tissue (SAT) aromatase expression, and parameters of the hypothalamic-pituitary-gonadal axis. We recruited 57 morbidly obese men [33 had type 2 diabetes (DM2)] and 25 normal-weight men undergoing abdominal surgery. Fourteen obese men also attended a follow-up, 2 years after gastric bypass surgery (GBS). Circulating T levels were quantified by LC-MS/MS, whereas free T levels were measured using serum equilibrium dialysis and sex hormone-binding globulin, luteinizing hormone, and follicle-stimulating hormone by immunoassay. SAT biopsies were used to determine adipocyte cell size and aromatase expression by real-time PCR. Total and free T levels were decreased in obese males versus controls, with a further decrease in obese men with DM2 versus obese men without DM2. There were no differences in aromatase expression among the study groups, and sex steroids did not correlate with aromatase expression. Pearson analysis revealed an inverse association between (free) T and SAT cell size, triglycerides, and HOMA-IR. Multivariate analysis confirmed the inverse association between (free) T and SAT cell size (β = -0.321, P = 0.037 and β = -0.441, P = 0.011, respectively), independent of age, triglycerides, HOMA-IR, obesity, or diabetes. T levels were normalized 2 years after GBS. These data suggest that SAT cell size rather than SAT aromatase expression or parameters of the hypothalamic-pituitary-gonadal axis is related to low T in male obesity, which points to adipose cell size-related metabolic changes as a major trigger in decreased T levels.

Androgen Deficiency and Erectile Dysfunction in Patients with Type 2 Diabetes

BACKGROUND

The association between type 2 diabetes mellitus (T2DM) and low total serum testosterone (LST) has been identified in several cross-sectional studies.

OBJECTIVES

To assess the prevalence of androgen deficiency and erectile dysfunction (ED) and their relation to glycemic control within a sample of Egyptian men with T2DM.

RESEARCH DESIGN AND METHODS

A cross-sectional study including 70 men having T2DM. Their ages ranged from 30 to 50 years. They were evaluated for symptoms of androgen deficiency and ED, using a validated Arabic-translated Androgen Deficiency in Aging Males questionnaire and five-items version of the International Index of Erectile Function-5, respectively. Total testosterone (TT), glycated hemoglobin (HbA1c), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin were measured for all study subjects. Penile hemodynamics was assessed using penile duplex study for subjects who gave history of ED.

RESULTS

LST was found in 40% of studied men, and 92.9% of them reported overt symptoms of androgen deficiency. ED was detected in 85.7% of those with LST, as opposed to 31.0% of those with normal TT (P < 0.000). TT was lower in diabetic men with ED compared to those without ED (12.04 ± 5.36 vs 17.11 ± 7.11 nmol/L, P < 0.001). Significant negative correlation was found between TT and age, body mass index, waist circumference, systolic and diastolic blood pressures, and HBA1c (P < 0.00). FSH, LH, and prolactin levels were within the normal reference range in all subjects. HbA1c was higher in patients who had LST with ED, compared to those with normal TT and without ED. However, multivariate logistic regression analysis did not reveal a significant association between HBA1c and LST levels.

CONCLUSION

LST, symptoms of androgen deficiency, and ED are common in the studied sample of Egyptian men with T2DM. Inappropriately normal FSH and LH in face of LST may denote a state of hypogonadotropic hypogonadism. HBA1c was found to be more significantly associated with ED than with LST.

Protective effects of metformin on reproductive function in obese male rats induced by high-fat diet

PURPOSE

The study aims to elucidate the changes in testicular spermatogenic function in high-fat diet (HFD)-induced obese rats and to evaluate the protective effects of metformin intervention.

METHODS

Male Sprague-Dawley rats (n = 18) were randomly divided into a control group (standard diet), an HFD group, and a metformin group (HFD + metformin at 100 mg/kg, once daily by oral gavage). After 8 weeks, rats were euthanized, and the weights of body and testes were measured. Testis and epididymis were dissected and hematoxylin-eosin-stained for histopathological examination and semen parameter analysis. Blood samples were collected for assessment of sex hormones and metabolic parameters (serum glucose, insulin, and leptin). Spermatogenic cell apoptosis was accessed by TUNEL.

RESULTS

Compared with the control group, the final body weight and weight gain were significantly higher in HFD rats, while the testicle weight and coefficients were lower. In HFD rats, metformin treatment induced weight loss and increased testicle weight (P < 0.05). In HFD rats, obvious pathological changes in the testicular tissue were characterized by small, atrophic, and distorted seminiferous tubules and destroyed basement membrane. Metformin treatment protected against the HFD-induced decrease in the number of spermatogonia, Sertoli cells, and Leydig cells (P < 0.05); ameliorated the HFD-induced increases in serum glucose, insulin, leptin, and estrogen; and decreased serum testosterone (P < 0.05) and reduced the rate of testicular cell apoptosis in obese male rats. Finally, metformin significantly improved semen parameters (including concentration, viability, motility, and normal morphology) in HFD rats (P < 0.05).

CONCLUSIONS

HFD-induced obesity in rats results in detrimental effects on spermatogenesis, semen quality, endogenous hormones, and testicular cell apoptosis. Metformin intervention improved the semen parameters, possibly due to its effects on weight loss, increased testicular weight, reduced testicular cell apoptosis, and resulted in restoration of hormonal homeostasis and correction of metabolic disorder.

Bone loss in obesity and obstructive sleep apnea: a review of literature

INTRODUCTION

Obstructive sleep apnea (OSA) is a common sleep-related respiratory disorder. It is associated with many endocrinopathies including hypogonadotropic hypogonadism, hypercortisolism, and glucose intolerance that may lead to bone loss with secondary osteoporosis.

METHODS

We report the case of a 41-year-old man who presented with bilateral 9th rib fractures and was found to have obstructive sleep apnea and osteoporosis. We also present a literature review on this topic.

RESULTS

OSA can lead to bone loss through various mechanisms. Some are shared with obesity, including hypogonadism, altered adrenergic tone, inflammation, oxidative stress, vitamin D deficiency and diabetes mellitus; others are specific to OSA, such as hypoxia and altered glucocorticoids regulation.

CONCLUSION

There are no guidelines on screening for osteoporosis in OSA. Further research is needed to assess the incidence of bone loss and fractures in OSA.

Influence of Testosterone Replacement Therapy on Metabolic Disorders in Male Patient with Type 2 Diabetes Mellitus and Androgen Deficiency

INTRODUCTION: Multiple epidemiological studies have shown that low testosterone levels are associated with and predict the future development of T2DM.AIM: The aim of study was to show the influence of testosterone replacement therapy on anthropometric characteristics, glycosylated hemoglobinlevel level, blood pressure and dyslipidemia in patients with T2DM and Androgen deficiency.MATERIALS AND METHODS:  From 125 male patients with T2DM were randomized 85 subjects with age 49.8 ± 6.74 and BMI from 35.83 ± 3.65 kg/m2 in placebo-controlled study. We divided patients into two groups: 1) Treatment group, where was used testosterone replacement therapy. 2) Placebo group, where was used placebo. In both groups was added Life style modification, but Antidiabetic therapy was unchanged.RESULTS: After six months of treatment we repeated the diagnostic assessments: lipid profile was improved in both groups but in group I it was statistically significant. Free testosterone level increased in all groups but in group I it was statistically significant. HbA1c decreased in both group but in group I we had the best result. Blood pressure was reduced in both groups, results were similar.CONCLUSION: Our study demonstrated that it is possible to regulate blood pressure, lipid profile, HbA1c, BMI - by raising testosterone in diabetic men with androgen deficiency.

Testosterone supplementation therapy in the treatment of patients with metabolic syndrome

Metabolic syndrome (MetS) comprises a clinical complex of patient risk factors, including increased waist circumference, high triglyceride levels, low high-density lipoprotein cholesterol level, high blood pressure, and insulin resistance, the presence of which increases the likelihood of developing diabetes and cardiovascular disease. With a quarter of the American adult population affected, MetS and type 2 diabetes mellitus have been referred to as the most significant public health threats of the 21st century. Lifestyle modification and weight loss are recommended, however, no specific pharmacologic treatment is known. Given that low levels of testosterone have been implicated in the pathogenesis of MetS and an inverse relationship exists between circulating testosterone levels and the development of MetS, it is tempting to speculate that men with MetS may benefit from testosterone supplementation therapy. As such, our review examines the role of testosterone and the use of testosterone supplementation therapy as a treatment in men with MetS.

Acute and chronic effects of resistance exercise on the testosterone and cortisol responses in obese males: a systematic review

The biosynthesis and metabolism of testosterone and cortisol are altered by the high levels of adipose tissue and the constant state of low-grade inflammation of obesity. Resistance exercise (REx) has become one of the main lifestyle interventions prescribed to obese individuals due to its ability to positively influence body composition and some biomarkers, such as cholesterol and insulin resistance. Yet, little research has been done in obese examining the effects of REx on the testosterone and blood cortisol responses, two integral hormones in both exercise and obesity. The obese testosterone response to REx and whether or not it is blunted compared to lean individuals remains elusive. Conflicting findings concerning the blood cortisol response have also been reported, likely due to variance in REx protocol and the level of obesity in the participants in studies. Comparatively, both of these hormones have been extremely well studied in untrained lean males, which could be used as a basis for future research in obese males. However, without this endocrinological information, it is unknown if the current acute REx prescriptions are appropriate for eliciting a favorable acute endocrinological response, and ultimately, a positive chronic adaptation in obese males.

Evaluation of Resettin® on serum hormone levels in sedentary males

Background

Comparisons of hormones such as dihydrotestosterone (DHT), estradiol (E2), and testosterone indicate their impact on metabolism and body composition. While less is known regarding DHT and E2, testosterone is an androgenic metabolic hormone capable of positively regulating a variety of anabolic and androgenic processes in the body. Accordingly, it has been postulated that the age-related reduction in serum testosterone levels leads to reductions in lean muscle mass, bone mineral density, and other physical conditions that impair physical performance and decrease quality of life. Preliminary studies suggest that key ingredients found in Resettin®/MyTosterone™, a natural supplement containing the carotenoid astaxanthin from Haematococcus pluvialis and Saw Palmetto berry lipid extract from Serenoa repens, could positively impact testosterone levels. To investigate the clinical efficacy of Resettin®, the serum profiles of testosterone, E2 and DHT in healthy sedentary males before and after Resettin® treatment were evaluated in a randomized, placebo controlled clinical trial.

Method

Twenty healthy, sedentary men between the ages of 21 and 70 were randomized into either an 800 mg/day or 1200 mg/day Resettin®/MyTosterone™ treatment group or lecithin, which was used as the placebo. After a 14-day treatment period, there was a 14-day washout period. After the wash-out period, participants were crossed over within their respective group to either Resettin®/MyTosterone™ or the lecithin placebo for 14 days.

Results

After 14 days, participants receiving 800 mg per day of Resettin® had significantly reduced baseline-subtracted serum DHT levels in comparison to the placebo control group. While after 14 days, participants receiving 1200 mg per day of Resettin® had significantly reduced baseline-subtracted serum DHT and E2 levels in comparison to the placebo control group. Moreover, participants receiving 1200 mg per day of Resettin® experienced a 38% increase in serum testosterone levels in comparison to the placebo control group, but the effect did not reach statistical significance.

Conclusion

Although additional studies will be required to evaluate how Resettin® may promote proper testosterone regulation, these findings indicate that Resettin® can favorably influence serum hormone profiles in men.

Testosterone, sex hormone-binding globulin and the metabolic syndrome in men: an individual participant data meta-analysis of observational studies

Background

Low total testosterone (TT) and sex hormone-binding globulin (SHBG) concentrations have been associated with the metabolic syndrome (MetS) in men, but the reported strength of association varies considerably.

Objectives

We aimed to investigate whether associations differ across specific subgroups (according to age and body mass index (BMI)) and individual MetS components.

Data sources

Two previously published meta-analyses including an updated systematic search in PubMed and EMBASE.

Study Eligibility Criteria

Cross-sectional or prospective observational studies with data on TT and/or SHBG concentrations in combination with MetS in men.

Methods

We conducted an individual participant data meta-analysis of 20 observational studies. Mixed effects models were used to assess cross-sectional and prospective associations of TT, SHBG and free testosterone (FT) with MetS and its individual components. Multivariable adjusted odds ratios (ORs) and hazard ratios (HRs) were calculated and effect modification by age and BMI was studied.

Results

Men with low concentrations of TT, SHBG or FT were more likely to have prevalent MetS (ORs per quartile decrease were 1.69 (95% CI 1.60-1.77), 1.73 (95% CI 1.62-1.85) and 1.46 (95% CI 1.36-1.57) for TT, SHBG and FT, respectively) and incident MetS (HRs per quartile decrease were 1.25 (95% CI 1.16-1.36), 1.44 (95% 1.30-1.60) and 1.14 (95% 1.01-1.28) for TT, SHBG and FT, respectively). Overall, the magnitude of associations was largest in non-overweight men and varied across individual components: stronger associations were observed with hypertriglyceridemia, abdominal obesity and hyperglycaemia and associations were weakest for hypertension.

Conclusions

Associations of testosterone and SHBG with MetS vary according to BMI and individual MetS components. These findings provide further insights into the pathophysiological mechanisms linking low testosterone and SHBG concentrations to cardiometabolic risk.

Leptin level and oxidative stress contribute to obesity-induced low testosterone in murine testicular tissue

Objective. This study evaluated the effects of obesity on the function of reproductive organs in male mice and the possible mechanism of male secondary hypogonadism (SH) in obesity. Methods. Ninety-six mice were randomly assigned to three groups: the control group, diet-induced obesity group, and diet-induced obesity resistant group for 8 weeks and 19 weeks. The effects of short- and long-term high-fat diet on the reproductive organs were determined by measuring sperm count and motility, relative testis weight, testosterone level, pathological changes and apoptosis of Leydig cells. Oxidative stress was evaluated by determining malondialdehyde, H₂O₂, NO levels, and GSH in testis tissues. CAT, SOD, GSH-Px and Nrf₂ mRNA were measured by real-time PCR. Results. Short- and long-term high-fat diet decreased sperm count and motility, relative testis weight, testosterone level; decreased CAT, SOD, GSH-Px and Nrf₂ mRNA expression; increased MDA, H₂O₂, NO and leptin levels; inhibited the activity of CAT and GSH-Px enzymes. Pathological injury and apoptosis of Leydig cells were found in testis tissue. Conclusions. Pathological damage of Leydig cells, oxidative stress in testis tissue, and high level of leptin may provide some evidence to clarify the mechanisms of male SH in obesity.

Effects of five-year treatment with testosterone undecanoate on metabolic and hormonal parameters in ageing men with metabolic syndrome

Metabolic and hormonal modifications after long-term testosterone (T) treatment have never been investigated. 20 hypogonadal men (mean T = 241 ng/dL-8.3 nmol/L) with metabolic syndrome (MS, mean age 58) were treated with T-undecanoate injections every 12 weeks for 60 months. 20 matched subjects in whom T was unaccepted or contraindicated served as controls. Primary endpoints were variations from baseline of metabolic and hormonal parameters. In T-group, significant reductions in waist circumference (-9.6 ± 3.8 cm, P < 0.0001), body weight (-15 ± 2.8 Kg, P < 0.0001), and glycosylated hemoglobin (-1.6  ±  0.5%, P < 0.0001) occurred, along with improvements in insulin sensitivity (HOMA-I; -2.8  ±  0.6, P < 0.0001), lipid profile (total/HDL-cholesterol ratio -2.9 ± 1.5, P < 0.0001), systolic and diastolic blood pressure (-23 ± 10 and -16 ± 8 mm Hg, P < 0.0001, resp.), and neck and lumbar T-scores (+0.5 ± 0.15 gr/cm(2), P < 0.0001; +0.7 ± 0.8, P < 0.0001, resp.). Also, serum vitamin D (+14.0 ± 1.3 ng/mL, P < 0.01), TSH (- 0.9 ± 0.3 mUI/mL, P < 0.01), GH (0.74 ± 0.2 ng/mL, P < 0.0001), and IGF1 (105 ± 11 ng/mL, P < 0.01) levels changed in T-group but not in controls. Normalization of T levels in men with MS improved obesity, glycemic control, blood pressure, lipid profile, and bone mineral density compared with controls. Amelioration in hormonal parameters, that is, vitamin D, growth hormone, and thyrotropin plasma levels, were reported.

Thyroid hormone and leptin in the testis

Leptin is primarily expressed in white adipose tissue; however, it is expressed in the hypothalamus and reproductive tissues as well. Leptin acts by activating the leptin receptors (Ob-Rs). Additionally, the regulation of several neuroendocrine and reproductive functions, including the inhibition of glucocorticoids and enhancement of thyroxine and sex hormone concentrations in human beings and mice are leptin functions. It has been suggested that thyroid hormones (TH) could directly regulate leptin expression. Additionally, hypothyroidism compromises the intracellular integration of leptin signaling specifically in the arcuate nucleus. Two TH receptor isoforms are expressed in the testis, TRa and TRb, with TRa being the predominant one that is present in all stages of development. The effects of TH involve the proliferation and differentiation of Sertoli and Leydig cells during development, spermatogenesis, and steroidogenesis. In this context, TH disorders are associated with sexual dysfunction. An endocrine and/or direct paracrine effect of leptin on the gonads inhibits testosterone production in Leydig cells. Further studies are necessary to clarify the effects of both hormones in the testis during hypothyroidism. The goal of this review is to highlight the current knowledge regarding leptin and TH in the testis.

Testosterone levels and type 2 diabetes in men: current knowledge and clinical implications

The relationship between testosterone and diabetes is an important issue, given the fact that diabetes is becoming a fast-growing epidemic, the morbidity associated with which is more disabling than the disease itself. Various studies have demonstrated the increasing prevalence of hypogonadism in diabetic subjects, but whether this is a cause or effect is still an area of active research. The past couple of decades have witnessed an increasing rate of testosterone prescriptions, even though the relationship between testosterone therapy and cardiovascular effects is still not conclusive. The studies done in this regard have shown conflicting results, and there is still a dearth of long-term, follow-up studies in this field. This paper reviews in brief the postulated mechanisms, observational studies, and interventional data regarding the adverse effects of testosterone therapy in type 2 diabetes mellitus, stressing the cardiovascular risks.

Testosterone and insulin resistance in the metabolic syndrome and T2DM in men

Obesity, type 2 diabetes mellitus and the metabolic syndrome are major risk factors for cardiovascular disease. Studies have demonstrated an association between low levels of testosterone and the above insulin-resistant states, with a prevalence of hypogonadism of up to 50% in men with type 2 diabetes mellitus. Low levels of testosterone are also associated with an increased risk of all-cause and cardiovascular mortality. Hypogonadism and obesity share a bidirectional relationship as a result of the complex interplay between adipocytokines, proinflammatory cytokines and hypothalamic hormones that control the pituitary-testicular axis. Interventional studies have shown beneficial effects of testosterone on components of the metabolic syndrome, type 2 diabetes mellitus and other cardiovascular risk factors, including insulin resistance and high levels of cholesterol. Biochemical evidence indicates that testosterone is involved in promoting glucose utilization by stimulating glucose uptake, glycolysis and mitochondrial oxidative phosphorylation. Testosterone is also involved in lipid homeostasis in major insulin-responsive target tissues, such as liver, adipose tissue and skeletal muscle.

Hypogonadotropic hypogonadism in morbidly obese males is reversed after bariatric surgery

BACKGROUND

The effect of weight loss by bariatric surgery on gonadal hormones in morbidly obese males is not entirely known. The main objective of the study was to analyze gonadal hormonal changes after weight loss.

METHODS

An observational study was conducted before and after 12 months of weight loss at a clinical research center. Thirty-three men [age 40.5 ± 9.9, body mass index (BMI) 50.3 ± 6.1 kg/m(2)] undergoing bariatric surgery were included. The main outcome measures were as follows: changes in total (TT) and free testosterone (FT), estradiol (E2), sex hormone binding globulin (SHBG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), anti-Müllerian hormone (AMH), inhibin B, and prolactin (PRL).

RESULTS

Baseline prevalence of hypogonadism (defined by TT < 300 ng/dl or FT < 65 pg/ml) was 78.8 and 51.5%, respectively. Hypogonadal patients were older and showed inhibin B and AMH significantly lower than those with normal TT. BMI correlated negatively with TT, LH, and SHBG. Regression analyses showed a significant and independent association of hypogonadism with age (OR = 1.2, p = 0.01), BMI (OR = 1.3, p = 0.03), and AMH (OR = 0.4, p = 0.03) after adjustments. After 1 year, percentage of weight loss (%WL) was 18.8 ± 5.2%, and there was a significant increase of TT, FT, SHBG, and FSH and a decrease of E2 and PRL. Prevalence of persistent hypogonadism after surgery was 6% (low TT) and 15% (low FT). %WL was significantly associated with percent changes in SHBG (r = -0.4, p = 0.04), inhibin B (r = -0.4, p = 0.03), and AMH (r = -0.4, p = 0.01). Age and %WL were the only significant and independent parameters associated with %TT change.

CONCLUSIONS

Obesity-associated hypogonadism is very prevalent in males with morbid obesity and is mostly reversed after sustained weight loss by bariatric surgery.

Insulin directly regulates steroidogenesis via induction of the orphan nuclear receptor DAX-1 in testicular Leydig cells

Testosterone level is low in insulin-resistant type 2 diabetes. Whether this is due to negative effects of high level of insulin on the testes caused by insulin resistance has not been studied in detail. In this study, we found that insulin directly binds to insulin receptors in Leydig cell membranes and activates phospho-insulin receptor-β (phospho-IR-β), phospho-IRS1, and phospho-AKT, leading to up-regulation of DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1) gene expression in the MA-10 mouse Leydig cell line. Insulin also inhibits cAMP-induced and liver receptor homolog-1 (LRH-1)-induced steroidogenic enzyme gene expression and steroidogenesis. In contrast, knockdown of DAX-1 reversed insulin-mediated inhibition of steroidogenesis. Whether insulin directly represses steroidogenesis through regulation of steroidogenic enzyme gene expression was assessed in insulin-injected mouse models and high fat diet-induced obesity. In insulin-injected mouse models, insulin receptor signal pathway was activated and subsequently inhibited steroidogenesis via induction of DAX-1 without significant change of luteinizing hormone or FSH levels. Likewise, the levels of steroidogenic enzyme gene expression and steroidogenesis were low, but interestingly, the level of DAX-1 was high in the testes of high fat diet-fed mice. These results represent a novel regulatory mechanism of steroidogenesis in Leydig cells. Insulin-mediated induction of DAX-1 in Leydig cells of testis may be a key regulatory step of serum sex hormone level in insulin-resistant states.

Circulating free testosterone in obese men after bariatric surgery increases in parallel with insulin sensitivity

BACKGROUND AND AIM

Male hypogonadism has been linked to obesity and diabetes. We aimed to study the association of changes in insulin sensitivity and testosterone levels in severe obese patients submitted to bariatric surgery.

SUBJECTS AND METHODS

Prospective intervention study with twenty consecutive patients who underwent bariatric surgery studied before and after significant weight loss. Serum testosterone, SHBG, fasting glucose, and insulin were measured among others. Free testosterone was calculated with the Vermeulen formula and insulin sensitivity with the homeostatic model assessment (HOMA).

RESULTS

At baseline, thirteen patients had low total testosterone levels, whereas eight of these patients also had free testosterone levels below the reference range obtained from the control group. After bariatric surgery total testosterone, SHBG, and free testosterone significantly increased and achieved normal values in all evaluated patients. Insulin sensitivity improved in all of them. Multivariate linear regression showed that changes in fasting glucose (β=-1.868, p=0.001), insulin (β=-3.782, p=0.001), weight (β=-0.622, p=0.002), and SHBG (β=-0.635, p=0.022) were associated with changes in free testosterone (adjusted R2=0.936, F=26.613, p=0.001). When insulin resistance calculated by HOMA was in the model instead of insulin and glucose, it also was associated (β=-3.488, p=0.008) with free testosterone (adjusted R2=0.821, F=11.111, p=0.005).

CONCLUSIONS

Circulating tes tos terone in obese men increases after bariatric surgery in parallel with an improvement in insulin sensitivity.

Testosterone-induced effects on lipids and inflammation

Chronic pain has to be considered in all respects a debilitating disease and 10-20% of the world's adult population is affected by this disease. In the most general terms, pain is symptomatic of some form of dysfunction and (often) the resulting inflammatory processes in the body. In the study of pain, great attention has been paid to the possible involvement of gonadal hormones, especially in recent years. In particular, testosterone, the main androgen, is thought to play a beneficial, protective role in the body. Other important elements to be related to pain, inflammation, and hormones are lipids, heterogenic molecules whose altered metabolism is often accompanied by the release of interleukins, and lipid-derived proinflammatory mediators. Here we report data on interactions often not considered in chronic pain mechanisms.

Occurrence of erectile dysfunction, testosterone deficiency syndrome and metabolic syndrome in patients with abdominal obesity. Where is a sufficient level of testosterone?

AIM

The aim of this study was to determine the prevalence of erectile dysfunction (ED), testosterone deficiency syndrome (TDS), and metabolic syndrome in patients with abdominal obesity (AO) and the prevalence of morbidity at different levels of testosterone (TST).

BACKGROUND

Male sex hormones play an important role in ED and variety of TDS and may have influence on the development of metabolic syndrome. The number of men with AO which constitutes a serious health risk is continuously growing. Currently, there are different views that TST levels are already insufficient, and the patient should benefit from treatment.

OBJECTIVES

This study examined the association between ED, testosterone level and metabolic syndrome in men with AO.

DESIGN, SETTING, AND PARTICIPANTS

The study was carried out in an outpatient urology center of Urology Clinic and Obesity Center of the Clinic of Internal Medicine. There were 167 participants—men with AO which were examined as part of preventive examination.

METHODS

Hormonal, a complete urological and internal evaluation was carried out in every patient.

RESULTS AND LIMITATIONS

We found some degree of ED in 73% (122/167) in men with AO. The TST levels below 14 nmol/l had of these 122 patients 84 patients (68.9%) and 49 patients (40.2%) below 10 nmol/l. In this group of patients, we found 103/167 patients (61.7%) with metabolic syndrome. When we compared TST level and morbidity, we found significantly more patients with diabetes mellitus (DM), hypertension and dyslipidemia in group with TST below 10 nmol/l. We also found difference in the levels of HDL cholesterol and triglycerides in the group of patients with TST 10–14 and over 14 nmol/l.

CONCLUSION

Patients over 40 years of age with AO and ED should also be examined for TDS and metabolic syndrome. In this group of patients we found that 113/167 patients (67.6%) had total TST below 14 nmol/l, and sufficient level of TST seems to be above this level.

Leptin signaling and circuits in puberty and fertility

Leptin is an adipocyte-derived hormone involved in a myriad of physiological process, including the control of energy balance and several neuroendocrine axes. Leptin-deficient mice and humans are obese, diabetic, and display a series of neuroendocrine and autonomic abnormalities. These individuals are infertile due to a lack of appropriate pubertal development and inadequate synthesis and secretion of gonadotropins and gonadal steroids. Leptin receptors are expressed in many organs and tissues, including those related to the control of reproductive physiology (e.g., the hypothalamus, pituitary gland, and gonads). In the last decade, it has become clear that leptin receptors located in the brain are major players in most leptin actions, including reproduction. Moreover, the recent development of molecular techniques for brain mapping and the use of genetically modified mouse models have generated crucial new findings for understanding leptin physiology and the metabolic influences on reproductive health. In the present review, we will highlight the new advances in the field, discuss the apparent contradictions, and underline the relevance of this complex physiological system to human health. We will focus our review on the hypothalamic circuitry and potential signaling pathways relevant to leptin’s effects in reproductive control, which have been identified with the use of cutting-edge technologies of molecular mapping and conditional knockouts.

Psychological disturbances and quality of life in obese and infertile women and men

Anovulatory cycles and endometriosis are the main causes of female infertility. The most frequently anovulatory cycles are related to polycystic ovary syndrome (PCOS) commonly associated with obesity and hormonal disturbances in the course of obesity. Recently published studies revealed that infertility affects about one in six couples during their lifetime and is more frequent in obese. Obesity is also associated with male infertility related to erectile dysfunction, hormonal disturbances and lower semen quality. Any of these above mentioned disorder is the important risk factor of psychological disturbances and poor quality of life among women and men in the reproductive age. On the other hand the mood disorders may exacerbate the hormonal disturbances and worsen the effectiveness of infertility management. Infertility, its therapy with accompanying psychological disturbances may also significantly affect the partners relationships. The review summarize the results described in the current literature on the association between obesity and infertility and psychological disturbances as well as their impact on quality of life and sexual functioning in women and men. Moreover, the impact of infertility and psychological disturbances on partners relationships is discussed.