Chronotype and insomnia may affect the testosterone levels with a sexual difference: a Mendelian randomization.

OBJECTIVE: To evaluate the causal effects of sleep traits (i.e., chronotype, insomnia, and sleep duration) on bioavailable testosterone (BT), sex hormone-binding globulin (SHBG), and total testosterone (TT) levels in women and men. METHODS: We performed Mendelian randomization (MR) using random-effect inverse-variance weighted (IVW) and 7 other MR analyses. Exposure data for sleep traits were obtained from the largest-to-date genome-wide association study (GWAS) from 339,926 to 1,331,010 individuals. Summary data for testosterone levels were obtained from GWAS based on the UK Biobank. RESULTS: For women, our study supported that chronotype was associated with decreased BT (IVW: ß = - 0.042, 95% CI - 0.060, - 0.023, p = 1.17E-05) and TT (IVW: - 0.053, 95% CI - 0.075, - 0.031, p = 2.30E-06). Besides, insomnia can significantly increase BT (IVW: ß = 0.025, 95% CI 0.009, 0.041, p = 0.002). These findings were significant in most sensitivity analyses. For men, statistical significance was found between chronotype and BT (ß = - 0.027, 95% CI - 0.048, - 0.005, p = 0.016), and insomnia and TT (ß = - 0.028, 95% CI - 0.049, 0.007, p = 0.009) in IVW. However, the effect estimates were not broadly consistent with other sensitivity analyses. Our study did not find support for causal effects of sleep duration on testosterone levels in both women and men. CONCLUSION: Our study reveals the sex differences in the effects of sleep traits on testosterone levels. A healthy sleep habit is vital for the maintenance of testosterone homeostasis in women. Further studies are warranted to investigate the associations between sleep traits and testosterone levels in men.

Effect of body condition score on the testicular biometrical measures, semen characteristics and testosterone level in jackass.

This study was undertaken to evaluate the effect of body condition score (BCS) on testicle and epididymis biometrics, semen characteristics and testosterone level in Egyptian Jack. This study was conducted on 50 mature Jacks divided according to their body condition score into four groups: Poor (G1), moderate (G2), good (G3) and fat (G4). The complete testis was collected immediately after execution in the Giza Zoo abattoir; then, the epididymis was carefully dissected at the testicular junction. Biometrical measures including length, weight and volume were determined for the right and left testis and epididymis. Also, epididymal sperm was collected from all examined animas and evaluated for sperm concentration, progressive motility, viability and sperm abnormalities. Serum samples were collected for determination of total testosterone level. Results showed that the body condition score of the examined animal affects their biometrical measure of testicles and epididymis. There is a significant decrease (p < .05) in biometrical measures for the testicles and epididymis, sperm concentration, motility, viability and testosterone level in poor BCS animals (G1). The highest values were recorded in Good BCS (G3) Jacks. Conclusion: Jacks with good BCS (G3) should be selected for breeding activity in donkey.

Biotic and abiotic sounds affect calling activity but not plasma testosterone levels in male frogs (Batrachyla taeniata) in the field and in captivity.

In animals, the expression of diverse reproductive behaviors is hormonally regulated. In particular, vocalizing during courtship has been related to circulating androgen levels, and reciprocally, conspecific vocalizations are known to modulate androgen secretion in vertebrates. The effect of natural sounds of abiotic origin on hormonal status has virtually not received attention. Therefore, we evaluated the vocal responses of male Batrachyla taeniata frogs to conspecific chorus and rainfall sounds in natural and controlled laboratory settings, measuring the testosterone levels of exposed individuals. In field and laboratory conditions, testosterone levels of frogs exposed to 31.5 min of chorus and rain sounds and non-exposed individuals were similar. In the field, frogs increased their call rate in response to playbacks of chorus and rain sound, but the evoked calling activity was unrelated to plasma testosterone. In contrast to the field, frogs showed limited responsiveness to 31.5-min acoustic exposures in the laboratory. Similarly to the field, for vocally active males tested in the laboratory there was no association between call rate and testosterone levels. Additionally, in this group, testosterone levels were higher in vocally active males relative to non-calling individuals. Overall, these results indicate that in B. taeniata testosterone levels are not altered following a short-term exposure to conspecific biotic and to abiotic sounds. Our results are suggestive of a threshold influence of testosterone on the vocal activity of the species studied. Further explorations of the influence of abiotic sounds on endocrine activation are required to understand how animals respond to variable acoustic environmental conditions.

Testosterone therapy may reduce prostate cancer risk due to testosterone deficiency at a young age via stabilizing serum testosterone levels.

Objectives: To investigate whether testosterone replacement therapy (TRT) reduces prostate cancer (PCa) risk via stabilizing serum testosterone (T) levels beyond simply elevating serum T levels and whether TRT reduces PCa risk due to low serum T levels at a young age.Methods: We analyzed data of 776 hypogonadal men from a urology center in Bremerhaven, Germany through 2004-2016 to investigate whether the TRT group has more stable T levels and whether TRT can reduce the risk of PCa due to low serum T levels at an early age. We derived an index, Maximum Decline of T Relative to Baseline (MDRB), to describe the magnitude of T declines and variations over time.Results: We found the TRT group has more stable serum T levels (e.g. smaller drop-offs) during the follow-up period as compared to the non-TRT group, and the mean of MDRB is significantly higher in the untreated group (1.553 nmol/L VS 0.013 nmol/L; p-value < .001). TRT significantly reduces the risk of PCa associated with T deficiency at a young age (p-value = .00087).Conclusions: TRT may reduce PCa risk via maintaining serum T levels within individual's normal range; T surveillance may be needed for males who have low serum T levels at a young age to monitor abnormal variations of T levels and ensure timely treatment when necessary to reduce PCa risk.

Speech Acoustic Features: A Comparison of Gay Men, Heterosexual Men, and Heterosexual Women.

Potential differences between homosexual and heterosexual men have been studied on a diverse set of social and biological traits. Regarding acoustic features of speech, researchers have hypothesized a feminization of such characteristics in homosexual men, but previous investigations have so far produced mixed results. Moreover, most studies have been conducted with English-speaking populations, which calls for further cross-linguistic examinations. Lastly, no studies investigated so far the potential role of testosterone in the association between sexual orientation and speech acoustic features. To fill these gaps, we explored potential differences in acoustic features of speech between homosexual and heterosexual native French men and investigated whether the former showed a trend toward feminization by comparing theirs to that of heterosexual native French women. Lastly, we examined whether testosterone levels mediated the association between speech acoustic features and sexual orientation. We studied four sexually dimorphic acoustic features relevant for the qualification of feminine versus masculine voices: the fundamental frequency, its modulation, and two understudied acoustic features of speech, the harmonics-to-noise ratio (a proxy of vocal breathiness) and the jitter (a proxy of vocal roughness). Results showed that homosexual men displayed significantly higher pitch modulation patterns and less breathy voices compared to heterosexual men, with values shifted toward those of heterosexual women. Lastly, testosterone levels did not influence any of the investigated acoustic features. Combined with the literature conducted in other languages, our findings bring new support for the feminization hypothesis and suggest that the feminization of some acoustic features could be shared across languages.

Low Preoperative Prolactin Levels Predict Non-Organ Confined Prostate Cancer in Clinically Localized Disease.

INTRODUCTION: To evaluate the association between preoperative serum prolactin (PRL) levels and risk of non-organ confined prostate cancer (PCa) in clinically localized disease. MATERIALS AND METHODS: From December 2007 to December 2011, 124 patients with clinically localized PCa were retrospectively evaluated. Non-organ confined disease in the surgical specimen was defined according to extra-capsular extension, seminal vesicle invasion, positive surgical margins, and lymph node invasion. The association between clinical factors and serum levels of pituitary-testis hormones with the risk of non-organ confined disease was evaluated. RESULTS: Perioperative factors associated with non-organ confined disease include prostatic-specific antigen (OR 1.144; p = 0.025), proportion of biopsy positive cores (BPC, OR 36.702; p = 0.007), bioptical Gleason Score > 6 (OR 2.785; p = 0.034), and PRL (OR 0.756, p < 0.0001). The association was strong for BPC (area under the curve [AUC] 0.704; p < 0.0001) and PRL (AUC 0.299; p < 0.0001). When we dichotomized according to median value, PRL ≤7.7 µg/L was an independent predictor of extraprostatic disease (OR 6.571; p < 0.0001) with fair discrimination power (AUC 0.704; p < 0.0001). CONCLUSION: Low preoperative PRL levels predict the risk of non-organ confined PCa in clinically localized disease.

Correlation of testicular ultrasonography, testicular biometry, serum testosterone levels and seminal attributes in pre and post-pubertal age for breeding soundness evaluation in Osmanabadi bucks.

The present research work entitled "Correlation of testicular ultrasonography, testicular biometry, serum testosterone levels and seminal attributes in pre- and post-pubertal age for breeding soundness evaluation in Osmanabadi bucks" was undertaken in 18 healthy Osmanabadi bucks from the Instructional Livestock Farm Complex, Bombay Veterinary College, Mumbai, Maharashtra. The body weight (kg), scrotal circumference (cm) and testicular biometry (cm) of post-weaning 18 Osmanabadi male kids was recorded every 15 days from weaning, i.e., 120 ± 10 days along with serum testosterone (ng/ml) by radioimmunoassay method at monthly intervals for the next 6 months. Semen was collected six times on the seventh month onward during post-pubertal age at 15-day interval from 18 bucks. The semen was evaluated for macroscopic and microscopic tests. The body weight increased from 14.45 ± 0.67 to 19.57 ± 0.70 kg from four to nine and a half months of age. The average daily body weight gain was 31.27 g. Maximum body weight gain was 01.19 ± 0.16 kg from 5 to 6 followed by 01.15 ± 0.16 kg from 4 to 5 months of age. The scrotal circumference increased from 17.22 ± 0.56 to 19.03 ± 0.55 cm from four to nine and a half months of age with maximum increased between 4 and 5 followed by 6 and 7 months of age. The testicular length, width and thickness of right and left testicles were recorded by ultrasonography method. There was increase in mean right and left testicular length, width and thickness from 5.25 ± 0.19 to 5.84 ± 0.18 and 5.49 ± 0.21 to 6.16 ± 0.20; 2.99 ± 0.12 to 3.32 ± 0.12 and 3.10 ± 0.13 to 3.44 ± 0.12 and 2.97 ± 0.12 to 3.16 ± 0.12 and 3.06 ± 0.12 to 3.31 ± 0.11 cm, respectively by ultrasonography, between four to nine and a half months of age. Testicular length, width and thickness gain was at maximum in 5 to 6 months of age. Left testicular length was more than the right testis. Before puberty, there was sudden gain in body weight, testicular length and width. However, scrotal circumference showed significant increase after puberty. Body weight had highest correlation with ultrasonographic left testicular thickness (r = 1) followed by scrotal circumference, ultrasonographic right and left testicular width, left testicular length, right testicular length and thickness and least by right testicular thickness (r = 0.95). The semen was thin to thick in consistency and average semen density was 3.10 ± 0.05. Average semen volume was 0.81 ± 0.02 ml, mass activity, initial motility, live and dead sperm count, abnormal sperm count and sperm concentration were 3.45 ± 0.13, 76.16 ± 1.16 and 75.16 ± 1.28% and 24.84 ± 1.28, 12.30 ± 0.50% and 2631.04 ± 45.74 million/ml, respectively in 18 bucks in six collection at 15 days. There was significant rise in semen volume, mass activity, initial motility and concentration at 8.5 months and live count, density at 9 months of age which indicates the age of sexual maturity is 8.5 to 9 months in Osmanabadi bucks. The body weight had highest positive correlation with mass activity (r = 98) followed by initial motility, live sperm count and total sperm concentration, semen volume (r = 76). The scrotal circumference had highest positive correlation with initial motility (r = 98) followed by live sperm count, total sperm count, mass activity, semen volume (r = 86). On the other hand, body weight and scrotal circumference were negatively correlated with abnormal and dead sperm count. The mean testosterone concentration increased from 0.02 ± 0.004 to 5.75 ± 0.80 ng/ml between four and half to nine and half months of age, respectively. There was significant rise (p < 0.01) up to 1.38 ± 0.28 ng/ ml at 6.5 months, i.e., age of puberty and up to 5.75 ± 0.80 ng/ml at 9.5 months, i.e., age of sexual maturity. Testosterone had highest positive correlation with testicular length followed by testicular width, length, body weight and scrotal circumference, mass activity, live sperm count, initial motility, while it had highest negative correlation with dead and abnormal sperm count. From the present research work, it was concluded that the scrotal circumference, testicular length, width and thickness increased with increasing body weight. Before puberty, there was sudden gain in body weight, testicular length and width. However, scrotal circumference increased significantly at post-pubertal age. So testicular length, body weight, testicular width in pre pubertal age and scrotal circumference post-pubertal age can be used as indicator for selection of Osmanabadi bucks for breeding purpose. On the other hand, the semen parameters should consider only after 8.5 to 9 months of age for selection of Osmanabadi bucks for breeding.

Effect of Stevia rebaudiana Bertoni extract on sexual dysfunction in Streptozotocin-induced diabetic male rats.

Stevia rebaudiana Bertoni has been used locally as a non-calorie sweetener in medicine and diabetic diet which claimed to have aphrodisiac properties, although no scientific data of this function have been reported. The aim of this study was to investigate the effect of S. rebaudiana extract on sexual dysfunction, testosterone levels and number of Leydig cells in Streptozotocin (STZ)-induced diabetic male rats. A total of 28 diabetic male rats were randomly divided into 4 groups: diabetic group without any extract and 3 extract groups (5, 50 and 100 mg/kg). Seven normal control rats were treated with vehicle mount latency and frequency of (ML, MF), intromission latency and frequency (IL, IF), ejaculation latency and frequency of (EL, EF), the mount latency post ejaculation (MPE), the intromission latency post ejaculation (ILE), the intromission frequency post ejaculation (IFE) were recorded during 30 min on days 0, 14, 28. The serum testosterone levels, blood glucose, sex organs weight, number of leydig cells and histology of testicular tissue were measured. The stevia group (5 mg/kg) had a significant (p<0.05) increase in EF and IF. The number of Leydig cells in the diabetic group were significantly (p<0.05) reduced compared to the normal group and diabetic groups with extract (5 and 50 mg/kg). The serum testosterone levels and other sexual behaviors did not show any significant differences. The low- dose stevia extract with attention to antioxidant, vasodilator and anti-diabetic properties can be aphrodisiac in STZ- induced diabetic male rats.

Age-related testosterone declines can be detected in men's fingernails.

Testosterone plays multiple roles in the regulation of development, physiology, reproduction, and behavior. Age-related testosterone declines are expected in the population. However, measuring circulating testosterone is especially challenging because concentrations are labile, responding to social situations and challenges. Matrices that integrate long-term testosterone levels are therefore valuable as biomarkers of endogenous levels as well as chronic exposures. Here, we report on a simple method to extract and measure accumulated testosterone from human fingernails using commercial enzyme immunoassay kits. Furthermore, we demonstrate known human testosterone sex and age trends. Our method is especially useful for quantifying testosterone in men's nails, where a small amount of matrix is required. Thus, this approach is a potential tool for biomonitoring endogenous as well as exogenous testosterone exposure. We suggest considering nails as an alternative matrix for quantifying other steroids as well.

A novel approach to breast cancer prevention: reducing excessive ovarian androgen production in elderly women.

Minimizing endogenous estrogen production and activity in women at high risk for breast cancer is a prominent approach to prevention of the disease. A number of clinical trials have shown that the administration of selective-estrogen receptor modulators or aromatase inhibitors significantly reduces the incidence of breast cancer in healthy women. Unfortunately, these drugs often produce adverse effects on the quality of life and are, therefore, poorly accepted by many women, even those who are at high risk for breast cancer. We propose a novel alternative approach to decreasing estrogen production: suppression of ovarian synthesis of the androgen precursors of estrogens by administration of long-acting gonadotropin-releasing hormone analogs to women with ovarian stromal hyperplasia. The specific target population would be elderly postmenopausal women, at increased risk of breast cancer, and with high blood levels of testosterone, marker of ovarian hyperandrogenemia, and recognized factor of risk for breast cancer. Testosterone levels are measured at baseline to identify women at risk and during the follow-up to evaluate the effectiveness of therapy. The postmenopausal ovary is an important source of excessive androgen production which originates from the ovarian interstitial cell hyperplasia frequently present in breast cancer patients. We propose to counter the source of androgen excess in women with ovarian stromal hyperplasia, thus reducing the substrate for estrogen formation without completely inhibiting estrogen synthesis. Available evidence indicates that gonadotropin-releasing hormone analogs can be safely used for breast cancer prevention in postmenopausal women.

Diurnal testosterone variability is differentially associated with parenting quality in mothers and fathers.

Previous studies on the relation between testosterone (T) levels and parenting have found ample evidence for the challenge hypothesis, demonstrating that high T levels inhibit parental involvement and that becoming a parent is related to a decrease in T levels in both mothers and fathers. However, less is known about the relation between T levels and more qualitative aspects of parenting. In the current study we examined basal T levels and diurnal variability in T levels in relation to mothers' and fathers' parenting quality. Participants included 217 fathers and 124 mothers with two children (3 and 5years of age). Evening and morning salivary T samples were analyzed with radio-immunoassays to determine circulating T levels. Parental sensitivity (i.e., child-centered responsiveness) and respect for children's autonomy were observed during free play in the family home. The results showed that higher evening T levels in mothers were associated with more sensitivity to the oldest and youngest child. Diurnal T variability was more consistently associated with parenting behavior towards their children than basal T levels. For fathers, more diurnal variability in T was associated with more sensitivity and more respect for autonomy with their youngest children. For mothers, more diurnal variability in T was associated with less sensitivity to both children and less respect for the youngest child's autonomy. These findings suggest that the T system might act differently in relation to parenting behavior in males and females.

Higher androgen bioactivity is associated with excessive erythrocytosis and chronic mountain sickness in Andean Highlanders: a review.

Populations living at high altitudes (HA), particularly in the Peruvian Central Andes, are characterised by presenting subjects with erythrocytosis and others with excessive erythrocytosis (EE)(Hb>21 g dl(-1) ). EE is associated with chronic mountain sickness (CMS), or lack of adaptation to HA. Testosterone is an erythropoietic hormone and it may play a role on EE at HA. The objective of the present review was to summarise findings on role of serum T levels on adaptation at HA and genes acting on this process. Men at HA without EE have higher androstenedione levels and low ratio androstenedione/testosterone than men with EE, suggesting low activity of 17beta-hydroxysteroid dehydrogenase (17beta-HSD), and this could be a mechanism of adaptation to HA. Higher conversion of dehydroepiandrosterone to testosterone in men with EE suggests nigher 17beta-HSD activity. Men with CMS at Peruvian Central Andes have two genes SENP1, and ANP32D with higher transcriptional response to hypoxia relative to those without. SUMO-specific protease 1 (SENP1) is an erythropoiesis regulator, which is essential for the stability and activity of hypoxia-inducible factor 1 (HIF-1α) under hypoxia. SENP1 reverses the hormone-augmented SUMOylation of androgen receptor (AR) increasing the transcription activity of AR.In conclusion, increased androgen activity is related with CMS.

The Impact of Testosterone on Alzheimer's Disease Are Mediated by Lipid Metabolism and Obesity: A Mendelian Randomization Study.

BACKGROUND: To investigate the causal relationship between testosterone (BT) levels and Alzheimer's disease (AD) risk and to quantify the role of obesity and lipid metabolism as potential mediators. METHODS: We used a two-sample, two-step MR to determine:1) the causal effect of BT levels on AD; 2) the causal effect of two lipid metabolites, obesity and LDLc on AD; and 3) the mediating effects of these metabolites. Pooled data for BT levels and lipid metabolism were obtained from the UK Biobank. AD data were obtained from the Alzheimer's Disease Project International Genomics Consortium, FinnGen Consortium, and UK Biobank study. Effect estimates from external genome-wide association study (GWAS) pooled statistics were obtained using inverse variance-weighted (IVW) MR analysis. RESULTS: Higher levels of BT were associated with a reduced risk of AD (odds ratio [OR] 0.9992, 95% CI 0.9985-0.9998, P = 0.019), and there was a negative correlation with LDLc (OR 0.9208, 95% CI 0.8569-0.9895, P = 0.024) and obesity class 2 (OC2) (OR 0.7445, 95% CI 0.5873-0.9437, P = 0.014). Conversely, there was a positive correlation between LDLc (OR 1.0014, 95% CI 1.0000-1.0029, P = 0.043) and OC2 (OR 1.0005, 95% CI 1.0001-1.0009, P = 0.003) and AD. Mediation analysis showed that the indirect effect of BT levels on AD was achieved through LDLc and OC2, which accounted for 17% and 17% of the total effect, respectively. CONCLUSION: Our study identified a causal role of BT levels in LDLc and OC2. BT levels may affect AD through LDLc and OC2 metabolic processes.

Effects of eight-week regular high-intensity interval training and hemp (Cannabis sativa L.) seed on total testosterone level among sedentary young males: double-blind, randomized, controlled clinical trial.

PURPOSE: This study aimed to investigate the effects of high-intensity interval training (HIIT) alone or in combination with hemp seed on total testosterone (TT) levels, sex hormone-binding globulin (SHBG), body composition, oxidative stress, and antioxidant capacity in sedentary young males. METHODS: Randomly, 48 young sedentary males were assigned among four groups (each comprising 12 individuals) as follows: HIIT + hemp seed (HH), HIIT + placebo (AT), hemp seed only (HS), and control. For eight weeks, exercise groups had HIIT three times per week. Hemp seed groups received 2 g of powder daily. The plasma levels of TT, SHBG, catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), and also body mass index (BMI), body fat percentage (BF%), and muscle mass percentage (MM%) were measured. The analysis was based on the intention-to-treat (ITT) and per-protocol (PP). RESULTS: Based on ITT, BMI and BF% decreased, and MM% increased significantly post-intervention in HIIT groups (p < 0.05). TT increased significantly in the HH [mean difference 0.45, 95% CI 0.1 to 0.7, p = 0.005] and AT [mean difference 0.37, 95% CI 0.1 to 0.7, p = 0.01]. The whole hemp seed components showed a significant antioxidant potential. However, none of the SOD, CAT, and MDA indices showed significant changes post-interventions (p ≥ 0.05). CONCLUSION: Finally, HIIT and hemp seed intake showed no significant effects on the antioxidant defense system. However, regular HIIT significantly increased TT levels and improved body composition in sedentary young males. TRIAL REGISTRATION: Iranian Registry of Clinical Trials (registration code: IRCT20140907019082N10).

Effect of Varicocelectomy on Serum Follicle-Stimulating Hormone and Testosterone; The Interrelationship Between Hormonal Variables.

Purpose: The present study was conducted to analyze the effect of varicocelectomy on serum follicle-stimulating hormone (FSH) and testosterone. The interrelationship between seminal and hormonal variables is also investigated. Patients and Methods: A prospective cohort study was conducted on patients of the urology clinic from 2012 to 2017. The study was conducted in the Security Forces Hospital, in Riyadh, Saudi Arabia. Infertile patients who had already undergone the FSH examination and testosterone twice were included in the study. Statistical Package for Social Sciences (SPSS) version 21.0 was used to analyze the data. Results: A total of 186 patients were studied which reveals that the age group of 21-30 years was higher than other age groups 80 (43%), micro varicocelectomy was performed in 138 (74%) of patients and 79 (47%) patients had one-year infertility. The study assessed the effect of varicocelectomy on sperm count and motility serum FSH, testosterone, luteinizing hormone (LH), and prolactin, and it was found that none of the variables showed significant association after varicocelectomy, except for luteinizing hormone (P-value = 0.014). Testosterone levels in patients who had FSH ≤10 were also evaluated and it was found that the level of testosterone was increased with a decreased level of FSH (P-value = 0.005). Conclusion: It was concluded from our results that after varicocelectomy, those patients who had FSH levels ≤10 were found to have increased testosterone levels. LH was also found to be significant; however, other hormones were not found to be significant. This may occur due to the reason that we have the majority of the participants in the age group 21-30. Further prospective studies are needed to evaluate the association with ample sample size.

Prostate cancer radiotherapy and incidental testicular irradiation: Impact on gonadal function.

Incidental testicular irradiation during prostate cancer radiotherapy is rarely documented in literature and the long-term impact on gonadal function largely underreported. Here we present an overview of available data on incidental testicular irradiation and radiation-induced hypogonadism during prostate cancer radiotherapy and discuss future technical developments to minimize testis irradiation.

Changes in Organ Weight, Sperm Quality and Testosterone Levels After Aluminum (Al) and Indium (In) Administration to Wistar Rats.

BACKGROUND: Aluminum and indium are widely used in industrial manufacturing, in pharmaceutical products, in medical treatments, and in food packaging, so they could reach organisms by different way. In order to clarify whether these elements are dangerous, we already demonstrated the ultrastructural modifications observed in the testicles, the epididymides, and the seminal vesicles of rat. Their pro-oxidative effect was also confirmed concomitantly to a decrease in anti-oxidant defenses in the blood, the testicles, and the liver. Thus, it seemed very logic to evaluate damages in the reproductive organs, especially on the exocrine and endocrine functions of the testicles. METHODS: Aluminum and indium were intraperitoneally administered to male Wistar rats. Sperm solution was obtained from cauda epididymides. Motility, viability, density, and malformation of spermatozoa solution were assessed. Serum total unconjugated testosterone concentrations were measured using RIA technique. RESULTS: Our results showed a decrease in weight of the testicles, epididymides, and seminal vesicles of indium-treated rats and an increase in the weight of their kidneys. A decrease in motility, viability, and density of epididymides stored sperm as well as generation of many spermatozoa malformations was also observed especially in indium-treated rats. Testosterone levels were increased in indium but were enhanced in aluminum group. This confirmed our previous studies showing that aluminum and indium are toxic for the testicular tissues. This could be explained by the generation of reactive oxygen species (ROS) affecting strongly the exocrine and the endocrine functions of the testicles. CONCLUSION: Aluminum and indium are disturbing elements for the exocrine and endocrine functions of rat testicles.

Association between serum total testosterone levels and metabolic syndrome among adult women in the United States, NHANES 2011-2016.

Objective: To investigate the association between serum total testosterone (TT) levels and metabolic syndrome (MetS) or its components among adult women. Methods: 2,678 women from NHANES 2011-2016 were included in this cross-sectional study. MetS was determined according to the National Cholesterol Education Program Adult Treatment Panel III guidelines. The association between serum TT levels and MetS was evaluated by two logistics regression models and the adjusted restricted cubic spline (RCS). Stratified analysis and sensitive analysis were also conducted. Results: Continuous TT levels were negatively associated with the occurrence of MetS, and the ORs associated with per SD increase in ln TT were 0.70 (95%CI: 0.58-0.85) in 2011-2014 and 0.56 (95%CI: 0.39-0.79) in 2015-2016 in Model A. High TT group were less likely to have MetS (OR=0.60, 95%CI: 0.45-0.80 in 2011-2014 and OR=0.50, 95%CI: 0.32-0.78 in 2015-2016) when compared to the low TT group. When TT levels were divided into quartiles, TT levels were negatively correlated with the incidence of MetS (p for trend < 0.001). Similar trend was observed in Model B. Multivariate-adjusted logistic regression with RCS exhibited that TT had a L-shaped dose-response association with MetS or its components. Interaction analyses revealed that women who were less than 50 years old (OR=0.37, 95%CI: 0.22, 0.63), with depression (OR=0.50, 95%CI: 0.29, 0.87) or being smokers (OR=0.37, 95%CI: 0.23, 0.54) showed lower ORs than those who were over 50 years old (OR=0.66, 95%CI: 0.40, 1.09), without depression (OR=0.59, 95%CI: 0.41, 0.85) or non-smokers (OR=0.59, 95%CI: 0.39, 0.89) when measure the association between ln TT and the occurrence of MetS. Conclusions: Our study indicated that TT levels are negatively correlated with the occurrence of MetS, with interaction effects of age, smoke behaviors, and depressive status.

Body composition and testosterone in men: a Mendelian randomization study.

Background: Testosterone is an essential sex hormone that plays a vital role in the overall health and development of males. It is well known that obesity decreases testosterone levels, but it is difficult to determine the causal relationship between body composition and testosterone. Methods: To investigate potential causal associations between body composition and testosterone levels by a first time application of Mendelian randomization methods. Exposure variables in men included body composition (fat mass, fat-free mass, and body mass index). In addition to whole body fat and fat-free mass, we examined fat and fat-free mass for each body part (e.g., trunk, left arm, right arm, left leg and right leg) as exposures. Instrumental variables were defined using genome-wide association study data from the UK Biobank. Outcome variables in men included testosterone levels (total testosterone [TT], bioavailable testosterone [BT], and sex hormone-binding globulin [SHBG]). A one-sample Mendelian randomization analysis of inverse-variance weighted and weighted median was performed. Results: The number of genetic instruments for the 13 exposure traits related to body composition ranged from 156 to 540. Genetically predicted whole body fat mass was negatively associated with TT (ß=-0.24, P=5.2×10-33), BT (ß=-0.18, P=5.8×10-20) and SHBG (ß=-0.06, P=8.0×10-9). Genetically predicted whole body fat-free mass was negatively associated with BT (ß=-0.04, P=2.1×10-4), but not with TT and SHBG, after multiple testing corrections. When comparing the causal effect on testosterone levels, there was a consistent trend that the effect of fat mass was more potent than that of fat-free mass. There were no differences between body parts. Conclusion: These results show that reducing fat mass may increase testosterone levels.

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

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