Katsumata, Etsuko; Ueda, Yoko; Arai, Kazutoshi; Katsumata, Hiroshi; Kishimoto, Miori; Watanabe, Gen; Taya, Kazuyoshi
2012-03-01
This study is the first report on circulating testosterone and inhibin levels in a species of whales, the beluga. Circulating testosterone and immunoreactive (ir-) inhibin levels in two captive male belugas ("Nack", originally from Canada and "Duke", from the Okhotsk Sea) were measured every month for 9 years between 1995 and 2003. Assuming that clearly increased testosterone levels in the circulation indicates that the belugas had reached sexual maturity, at the ages of 10 ("Nack") and 11 years old ("Duke"). Their testosterone levels before the significant increase (pre-pubertal) were 0.42 ± 0.07 ng/ml (n=18) and 0.35 ± 0.10 ng/ml (n=18) and, those of after the increase (maturity) were 1.65 ± 0.14 ng/m l (n=74) and 2.06 ± 0.14 ng/ml (n=74). Circulating ir-inhibin levels before sexual maturity were 0.78 ± 0.04 ng/ml (n=18) and 0.64 ± 0.04 ng/ml (n=15) and, after sexual maturity were 0.52 ± 0.02 ng/ml (n=56) and 0.43 ± 0.02 ng/ml (n=67). Seasonal changes were observed in the testosterone levels after sexual maturity and the levels increased during March and April in Canadian origin "Nack", and peaked in February in Okhotsk origin "Duke". Circulating ir-inhibin level gradually decreased as they aged. A negative correlation between the circulating testosterone and ir-inhibin was observed. No seasonal changes were observed in the ir-inhibin levels after sexual maturity. These data will surely correspond to clarification of endocrinology and the successful reproduction of the beluga.
Yeap, Bu B; Grossmann, Mathis; McLachlan, Robert I; Handelsman, David J; Wittert, Gary A; Conway, Ann J; Stuckey, Bronwyn Ga; Lording, Douglas W; Allan, Carolyn A; Zajac, Jeffrey D; Burger, Henry G
2016-08-15
This article, Part 1 of the Endocrine Society of Australia's position statement on male hypogonadism, focuses on assessment of male hypogonadism, including the indications for testosterone therapy. (Part 2 will deal with treatment and therapeutic considerations.) Key points and recommendations are:Pathological hypogonadism arises due to diseases of the hypothalamus or pituitary gland (hypogonadotropic hypogonadism) or testes (hypergonadotropic hypogonadism). It is a clinical diagnosis with a pathological basis, confirmed by hormone assays.Hormonal assessment is based on measurement of circulating testosterone, luteinising hormone (LH) and follicle-stimulating hormone (FSH) concentrations. Measurement of sex hormone-binding globulin levels can be informative, but use of calculated free testosterone is not recommended for clinical decision making.Testosterone replacement therapy is warranted in men with pathological hypogonadism, regardless of age.Currently, there are limited data from high-quality randomised controlled trials with clinically meaningful outcomes to justify testosterone treatment in older men, usually with chronic disease, who have low circulating testosterone levels but without hypothalamic, pituitary or testicular disease.Obesity, metabolic syndrome and type 2 diabetes are associated with lowering of circulating testosterone level, but without elevation of LH and FSH levels. Whether these are non-specific consequences of non-reproductive disorders or a correctable deficiency state is unknown, but clear evidence for efficacy and safety of testosterone therapy in this setting is lacking.Glucocorticoid and opioid use is associated with possibly reversible reductions in circulating testosterone level, without elevation of LH and FSH levels. Where continuation of glucocorticoid or opioid therapy is necessary, review by an endocrinologist may be warranted.Changes in management as result of the position statement: Men with pathological hypogonadism should be identified and considered for testosterone therapy, while further research is needed to clarify whether there is a role for testosterone in these other settings.
Malan, Nicolaas T; von Känel, Roland; Schutte, Alta E; Huisman, Hugo W; Schutte, Rudolph; Smith, Wayne; Mels, Carina M; Kruger, Ruan; Meiring, Muriel; van Rooyen, Johannes M; Malan, Leoné
2013-10-12
Low testosterone, acute and chronic stress and hypercoagulation are all associated with hypertension and hypertension-related diseases. The interaction between these factors and future risk for coronary artery disease in Africans has not been fully elucidated. In this study, associations of testosterone, acute cardiovascular and coagulation stress responses with fibrinogen and von Willebrand factor in African and Caucasian men in a South African cohort were investigated. Cardiovascular variables were studied by means of beat-to-beat and ambulatory blood pressure monitoring. Fasting serum-, salivary testosterone and citrate coagulation markers were obtained from venous blood samples. Acute mental stress responses were evoked with the Stroop test. The African group demonstrated a higher cardiovascular risk compared to Caucasian men with elevated blood pressure, low-grade inflammation, chronic hyperglycemia (HbA1c), lower testosterone levels, and elevated von Willebrand factor (VWF) and fibrinogen levels. Blunted testosterone acute mental stress responses were demonstrated in African males. In multiple regression analyses, higher circulating levels of fibrinogen and VWF in Africans were associated with a low T environment (R(2) 0.24-0.28; p≤0.01), but only circulating fibrinogen in Caucasians. Regarding endothelial function, a low testosterone environment and a profile of augmented α-adrenergic acute mental stress responses (diastolic BP, D-dimer and testosterone) were associated with circulating VWF levels in Africans (Adj R(2) 0.24; p<0.05). An interdependence between acute mental stress, salivary testosterone, D-dimer and vascular responses existed in African males in their association with circulating VWF but no interdependence of the independent variables occurred with fibrinogen levels. © 2013.
Effects of centrifugation stress on pituitary-gonadal function in male rats
NASA Technical Reports Server (NTRS)
Gray, G. D.; Smith, E. R.; Damassa, D. A.; Davidson, J. M.
1980-01-01
The effects of centrifugation for various lengths of time on circulating levels of luteinizing hormone (LH) and testosterone in male rats were investigated. In a chronic 52-day experiment, centrifugation at 4.1 G significantly reduced LH and testosterone levels for the entire period. Centrifugation at 2.3 G had less effect inasmuch as LH levels were not significantly decreased and testosterone levels were significantly reduced only during the first few days of centrifugation. In more acute experiments, centrifugation at 4.1 G for 4 h resulted in reduced testosterone levels, whereas centrifugation for 15 min did not significantly alter the hormone levels. These results indicate that centrifugation can decrease circulating LH and testosterone levels if the gravitational force is of sufficient magnitude and is maintained for a period of hours. Chronic centrifugation may also inhibit the acute excitatory response of LH to handling and ether stress.
Béziers, Paul; Ducrest, Anne-Lyse; Simon, Céline; Roulin, Alexandre
2017-09-01
Knowledge of how and why secondary sexual characters are associated with sex hormones is important to understand their signalling function. Such a link can occur if i) testosterone participates in the elaboration of sex-traits, ii) the display of an ornament triggers behavioural response in conspecifics that induce a rise in testosterone, or iii) genes implicated in the elaboration of a sex-trait pleiotropically regulate testosterone physiology. To evaluate the origin of the co-variation between melanism and testosterone, we measured this hormone and the expression of enzymes involved in its metabolism in feathers of barn owl (Tyto alba) nestlings at the time of melanogenesis and in adults outside the period of melanogenesis. Male nestlings displaying smaller black feather spots had higher levels of circulating testosterone, potentially suggesting that testosterone could block the production of eumelanin pigments, or that genes involved in the production of small spots pleiotropically regulate testosterone production. In contrast, the enzyme 5α-reductase, that metabolizes testosterone to DHT, was more expressed in feathers of reddish-brown than light-reddish nestlings. This is consistent with the hypothesis that testosterone might be involved in the expression of reddish-brown pheomelanic pigments. In breeding adults, male barn owls displaying smaller black spots had higher levels of circulating testosterone, whereas in females the opposite result was detected during the rearing period, but not during incubation. The observed sex- and age-specific co-variations between black spottiness and testosterone in nestling and adult barn owls may not result from testosterone-dependent melanogenesis, but from melanogenic genes pleiotropically regulating testosterone, or from colour-specific life history strategies that influence testosterone levels. Copyright © 2017 Elsevier Inc. All rights reserved.
Ji, Ellen; Weickert, Cynthia Shannon; Lenroot, Rhoshel; Catts, Stanley V; Vercammen, Ans; White, Christopher; Gur, Raquel E; Weickert, Thomas W
2015-06-01
Growing evidence suggests that testosterone may play a role in the pathophysiology of schizophrenia given that testosterone has been linked to cognition and negative symptoms in schizophrenia. Here, we determine the extent to which serum testosterone levels are related to neural activity in affective processing circuitry in men with schizophrenia. Functional magnetic resonance imaging was used to measure blood-oxygen-level-dependent signal changes as 32 healthy controls and 26 people with schizophrenia performed a facial emotion identification task. Whole brain analyses were performed to determine regions of differential activity between groups during processing of angry versus non-threatening faces. A follow-up ROI analysis using a regression model in a subset of 16 healthy men and 16 men with schizophrenia was used to determine the extent to which serum testosterone levels were related to neural activity. Healthy controls displayed significantly greater activation than people with schizophrenia in the left inferior frontal gyrus (IFG). There was no significant difference in circulating testosterone levels between healthy men and men with schizophrenia. Regression analyses between activation in the IFG and circulating testosterone levels revealed a significant positive correlation in men with schizophrenia (r=.63, p=.01) and no significant relationship in healthy men. This study provides the first evidence that circulating serum testosterone levels are related to IFG activation during emotion face processing in men with schizophrenia but not in healthy men, which suggests that testosterone levels modulate neural processes relevant to facial emotion processing that may interfere with social functioning in men with schizophrenia. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.
Cunningham, Rebecca L; Singh, Meharvan; O'Bryant, Sid E; Hall, James R; Barber, Robert C
2014-01-01
The use of testosterone among aging men has been increasing, but results from studies addressing the effectiveness of testosterone replacement therapy have been equivocal. Given our prior pre-clinical studies that reported a major influence of oxidative stress on testosterone's neuroprotective effects, we investigated whether the negative effects of testosterone on brain function were predicted by oxidative load. In order to test our hypothesis, we determined whether circulating total testosterone and luteinizing hormone correlated with cognition in a subset of the Texas Alzheimer's Research & Care Consortium (TARCC) cohort, consisting of Caucasian (n = 116) and Mexican-American (n = 117) men. We also assessed whether oxidative stress (as indexed by homocysteine levels) modified this relationship between sex hormones and cognition, and whether the levels of two antioxidants, superoxide dismutase-1 and glutathione S-transferase (GST), varied as a function of circulating testosterone. In a low oxidative stress environment, testosterone was positively associated with the level of the antioxidant, GST, while no deleterious effects on cognitive function were noted. In contrast, under conditions of high oxidative stress (homocysteine levels >12 μmol/L), testosterone and luteinizing hormone were associated with cognitive impairment, but only among Caucasians. The ethnic difference was attributed to significantly higher GST levels among Mexican-Americans. While testosterone may be beneficial under conditions of low oxidative stress, testosterone appears to have negative consequences under conditions of elevated oxidative stress, but only in Caucasians. Mexican-Americans, however, were protected from any deleterious effects of testosterone, potentially due to higher levels of endogenous antioxidant defenses such as GST.
Maggio, Marcello; Nicolini, Francesco; Cattabiani, Chiara; Beghi, Cesare; Gherli, Tiziano; Schwartz, Robert S; Valenti, Giorgio; Ceda, Gian Paolo
2012-07-01
Testosterone levels decrease with age. This decline is steeper during "critical illnesses". Cardiac surgery is a particular representative model of major clinical condition producing stress responses similar to those observed during severe nonsurgical illness. Cardiac revascularization with extracorporeal circulation is characterized by marked postoperative complications such as insulin resistance, a pro-inflammatory state, acute anemia and renal dysfunction. These phenomena are more evident in older subjects, who are particularly vulnerable in the post-operative state, a condition that has been recently termed as "acute postoperative frailty". We recently showed that in older men with low ejection fraction undergoing cardiac revascularization with extracorporeal circulation, there is a profound decline in anabolic hormones, including testosterone. After surgery testosterone concentration frequently declines to less than 200 ng/dl, a situation suggestive of overt hypogonadism. Since men with low testosterone levels have a high probability of developing mobility limitations, we considered this a rationale for the perioperative use of testosterone treatment in older men undergoing cardiac revasularization surgery. We hypothesized that testosterone supplementation at this time might attenuate the impressive post-surgical catabolic hormonal milieu. The aim of this manuscript is to elucidate an ongoing randomized clinical trial in older men (70+ years old) undergoing elective cardiovascular revascularization with extracorporeal circulation. This randomized clinical trial will evaluate the effects of intramuscular testosterone administration on clinical and functional outcomes in this population. The study will also address potential mechanisms underlying the expected beneficial effects of testosterone supplementation including improvement of insulin sensitivity, markers of inflammatory status and improved hemoglobin levels. Copyright © 2012 Elsevier Inc. All rights reserved.
Dasinger, John Henry; Fahling, Joel M.; Backstrom, Miles A.; Alexander, Barbara T.
2017-01-01
Placental insufficiency alters the intrauterine environment leading to increased risk for chronic disease including impaired glucose metabolism in low birth weight infants. Using a rat model of low birth weight, we previously reported that placental insufficiency induces a significant increase in circulating testosterone in male intrauterine growth-restricted offspring (mIUGR) in early adulthood that is lost by 12 months of age. Numerous studies indicate testosterone has a positive effect on glucose metabolism in men. Female growth-restricted littermates exhibit glucose intolerance at 6 months of age. Thus, the aim of this paper was to determine whether mIUGR develop impaired glucose metabolism, and whether a decrease in elevated testosterone levels plays a role in its onset. Male growth-restricted offspring were studied at 6 and 12 months of age. No impairment in glucose tolerance was observed at 6 months of age when mIUGR exhibited a 2-fold higher testosterone level compared to age-matched control. Fasting blood glucose was significantly higher and glucose tolerance was impaired with a significant decrease in circulating testosterone in mIUGR at 12 compared with 6 months of age. Castration did not additionally impair fasting blood glucose or glucose tolerance in mIUGR at 12 months of age, but fasting blood glucose was significantly elevated in castrated controls. Restoration of elevated testosterone levels significantly reduced fasting blood glucose and improved glucose tolerance in mIUGR. Thus, our findings suggest that the endogenous increase in circulating testosterone in mIUGR is protective against impaired glucose homeostasis. PMID:29145418
Ruige, Johannes B; Bekaert, Marlies; Lapauw, Bruno; Fiers, Tom; Lehr, Stefan; Hartwig, Sonja; Herzfeld de Wiza, Daniella; Schiller, Martina; Passlack, Waltraud; Van Nieuwenhove, Yves; Pattyn, Piet; Cuvelier, Claude; Taes, Youri E; Sell, Henrike; Eckel, Juergen; Kaufman, Jean-Marc; Ouwens, D Margriet
2012-07-01
Low testosterone accompanied by elevated estradiol associates with the development of metabolic dysfunction in men. The aim of the study was to explore the hypothesis that alterations in sex steroid levels induce metabolic dysfunction through adipokines. Circulating levels of sex steroids and 28 adipokines were determined in a cross-sectional study of morbidly obese men and aged-matched controls, as well as in a randomized clinical trial with healthy young men in which obesity-related alterations in sex steroid levels were mimicked by treatment with an aromatase inhibitor plus estradiol patches. Morbidly obese men had lower testosterone levels than normal-weight controls. Estradiol levels were increased in morbidly obese men (without DM2) as compared to normal-weight controls. Circulating levels of multiple proinflammatory cytokines, including IL-1Ra, IL-5, IL-6, IL-10, leptin, monocyte chemoattractant protein 1 (MCP1), and macrophage inflammatory protein 1α, positively associated with estradiol and negatively with testosterone. The associations with estradiol, but not with testosterone, remained significant after adjusting for adipocyte cell size. In a separate clinical trial, the direct adverse effects of lowering testosterone and raising estradiol on MCP1 were substantiated in vivo. Initial alterations in sex steroid levels may contribute to metabolic dysfunction through adverse effects on adipokine levels in obese men. The direct adverse effects on MCP1, a chemokine highly linked to the development of metabolic dysfunction, were substantiated in a trial mimicking obesity-related alterations of sex steroid levels in healthy young males.
Kjaer, Thomas Nordstrøm; Ornstrup, Marie Juul; Poulsen, Morten Møller; Jørgensen, Jens Otto Lunde; Hougaard, David Michael; Cohen, Arieh Sierra; Neghabat, Shadman; Richelsen, Bjørn; Pedersen, Steen Bønløkke
2015-09-01
Resveratrol is a naturally occurring polyphenol with purported inhibitory effects on prostate growth and cancer development. A number of studies have demonstrated that resveratrol reduces prostate growth in animal models and reduces prostate cell growth in vitro. Based on these pre-clinical findings, interest in resveratrol is increasing in relation to the management of benign prostate hyperplasia (BPH) and prostate cancer. So far, no human trials have evaluated the effects of resveratrol on circulating androgens, prostate size, or biochemical markers of prostate size. In a randomized placebo controlled clinical study using two doses of resveratrol (150 mg or 1,000 mg resveratrol daily) for 4 months, we evaluated the effects on prostate size, prostate specific antigen (PSA) and sex steroid hormones in 66 middle-aged men suffering from the metabolic syndrome(MetS). At baseline, prostate size and PSA were positively correlated (R = 0.34, P < 0.007) as was prostate size and age (R = 0.37, P < 0.003). Prostate size did not correlate with testosterone, free testosterone, dihydrotestosterone (DHT), or any other androgen precursor at baseline. The highest dose of resveratrol lowered the serum level of androstenedione 24% (P = 0.052), dehydroepiandrosterone (DHEA) 41% (P < 0.01), and dehydroepiandrosterone-sulphate (DHEAS) 50% (p<0.001), compared to the control group. However, prostate size and levels of PSA, testosterone, free testosterone and DHT remained unchanged. In this population of middle-aged men suffering from MetS, high dose resveratrol (1,000 mg daily) administration for 4 months significantly lowered serum levels of the androgen precursors androstenedione, DHEA and DHEAS, whereas prostate size and circulating levels of PSA, testosterone, free testosterone, and dihydrotestosterone were unaffected. The present study suggests that resveratrol does not affect prostate volume in healthy middle-aged men as measured by PSA levels and CT acquired prostate volumes. Consequently, we find no support for the use of resveratrol in the treatment of benign prostate hyperplasia. © 2015 Wiley Periodicals, Inc.
Amory, J K; Anawalt, B D; Bremner, W J; Matsumoto, A M
2001-01-01
Weekly intramuscular administration of testosterone esters such as testosterone enanthate (TE) suppresses gonadotropins and spermatogenesis and has been studied as a male contraceptive. For unknown reasons, however, some men fail to achieve azoospermia with such regimens. We hypothesized that either 1) daily circulating serum fluoroimmunoreactive gonadotropins were higher or testosterone levels were lower during the weekly injection interval, or 2) monthly circulating bioactive gonadotropin levels were higher in nonazoospermic men. We therefore analyzed daily testosterone and fluoroimmunoreactive gonadotropin levels as well as pooled monthly bioactive and fluoroimmunoreactive gonadotropin levels in normal men receiving chronic TE injections and correlated these levels with sperm production. After a 3-month control period, 51 normal men were randomly assigned to receive intramuscular TE at 25 mg (n = 10), 50 mg (n = 9), 100 mg (n = 10), 300 mg (n = 10), or placebo (n = 12) weekly for 6 months. After 5 months of testosterone administration, morning testosterone and fluoroimmunoreactive follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were measured daily for a 1-week period between TE injections. In addition, fluoroimmunoreactive and bioactive FSH and LH levels were measured in pooled monthly blood samples drawn just before the next TE injection. In the 100-mg and 300-mg TE groups, mean monthly fluoroimmunoreactive FSH and LH levels were suppressed by 86%-97%, bioactive FSH and LH levels by 62%-80%, and roughly half the subjects became azoospermic. In the 1-week period of month 6, daily testosterone levels between TE injections were within the normal range in men receiving placebo, or 25 or 50 mg of weekly TE, but were significantly elevated in men receiving 100 or 300 mg of weekly TE. At no point during treatment, however, were there significant differences in daily testosterone or fluoroimmunoreactive gonadotropin levels, or monthly bioactive gonadotropin levels between men achieving azoospermia and those with persistent spermatogenesis. This study, therefore, demonstrates that neither monthly nor daily differences in serum testosterone, or fluoroimmunoreactive or bioactive gonadotropins explain why some men fail to completely suppress their sperm counts to zero with weekly TE administration. Innate differences in the testicle's ability to maintain spermatogenesis in a low-gonadotropin environment may explain persistent spermatogenesis in some men treated with androgen-based contraceptive regimens.
Leblanc, Gerald A; Gooding, Meredith P; Sternberg, Robin M
2005-01-01
Over the past thirty years, a global occurrence of sexual aberration has occurred whereby females among populations of prosobranch snails exhibit male sex characteristics. This condition, called imposex, has been causally associated with exposure to the biocide tributyltin. Tributyltin-exposed, imposex snails typically have elevated levels of testosterone which have led to the postulate that this endocrine dysfunction is responsible for imposex. This overview describes recent evidence that supports this postulate. Gastropods maintain circulating testosterone levels and administration of testosterone to females or castrates stimulates male sex differentiation in several snail species. Studies in the mud snail (Ilyanassa obsoleta) have shown that gastropods utilize a unique strategy for regulating free testosterone levels. Excess testosterone is converted to fatty acid esters by the action of a testosterone-inducible, high capacity/low affinity enzyme, acyl-CoA:testosterone acyl transferase, and stored within the organisms. Free testosterone levels are regulated during the reproductive cycle apparently due to changes in esterification/desterification suggesting that testosterone functions in the reproductive cycle of the organisms. Testosterone esterification provides a unique target in the testosterone regulatory machinery of snails that is altered by tributyltin. Indeed, imposex and free testosterone levels were elevated in field collected snails containing high tin levels, while testosterone-fatty acid ester pools were reduced in these organisms. These observations indicate that tributyltin elevates free testosterone by reducing the retention of testosterone as fatty acid-esters. This endocrine effect of tributyltin may be responsible for imposex.
Gender differences in financial risk aversion and career choices are affected by testosterone.
Sapienza, Paola; Zingales, Luigi; Maestripieri, Dario
2009-09-08
Women are generally more risk averse than men. We investigated whether between- and within-gender variation in financial risk aversion was accounted for by variation in salivary concentrations of testosterone and in markers of prenatal testosterone exposure in a sample of >500 MBA students. Higher levels of circulating testosterone were associated with lower risk aversion among women, but not among men. At comparably low concentrations of salivary testosterone, however, the gender difference in risk aversion disappeared, suggesting that testosterone has nonlinear effects on risk aversion regardless of gender. A similar relationship between risk aversion and testosterone was also found using markers of prenatal testosterone exposure. Finally, both testosterone levels and risk aversion predicted career choices after graduation: Individuals high in testosterone and low in risk aversion were more likely to choose risky careers in finance. These results suggest that testosterone has both organizational and activational effects on risk-sensitive financial decisions and long-term career choices.
Brian L. Herting; James R. Belthoff
1997-01-01
Using a hormone implant protocol, we created treatment groups in which circulating levels of testosterone (T) were increased, decreased, or maintained at normal levels (controls) in male Western Screech-owls (Otus kennicottii). Owls were exposed to tape-recorded vocalizations of a conspecific, to which territory holders responded with aggression....
Juntti, Scott A; Tollkuhn, Jessica; Wu, Melody V; Fraser, Eleanor J; Soderborg, Taylor; Tan, Stella; Honda, Shin-Ichiro; Harada, Nobuhiro; Shah, Nirao M
2010-01-01
SUMMARY Testosterone and estrogen are essential for male behaviors in vertebrates. How these two signaling pathways interact to control masculinization of the brain and behavior remains to be established. Circulating testosterone activates the androgen receptor (AR) and also serves as the source of estrogen in the brain. We have used a genetic strategy to delete AR specifically in the mouse nervous system. This approach permits us to determine the function of AR in sexually dimorphic behaviors in males while maintaining circulating testosterone levels within the normal range. We find that AR mutant males exhibit masculine sexual and territorial displays, but they have striking deficits in specific components of these behaviors. Taken together with the surprisingly limited expression of AR in the developing brain, our findings indicate that testosterone acts as a precursor to estrogen to masculinize the brain and behavior, and signals via AR to control the levels of male behavioral displays. PMID:20435002
Testosterone-dependency of male solo song in a duetting songbird--evidence from females.
Voigt, Cornelia; Leitner, Stefan
2013-01-01
For male songbirds of the temperate zone there is a tight link between seasonal song behaviour and circulating testosterone levels. Such a relationship does not seem to hold for tropical species where singing can occur year-round and breeding seasons are often extended. White-browed sparrow weavers (Plocepasser mahali) are cooperatively breeding songbirds with a dominant breeding pair and male and female subordinates found in eastern and southern Africa. Each group defends an all-purpose territory year-round. While all group members sing duets and choruses, the most dominant male additionally sings a solo song that comprises a distinct and large syllable repertoire. Previous studies suggested this type of song being associated with reproduction but failed to support a relationship with males' circulating testosterone levels. The present study aimed to investigate the steroid hormone sensitivity of the solo song in more detail. We found that dominant males had significantly higher circulating testosterone levels than subordinates during the early and late breeding seasons. No changes in solo song characteristics were found between both time points. Further, experimental implantation of captive adult females with exogenous testosterone induced solo singing within one week of treatment. Such females produced male-typical song regarding overall structure and syllable composition. Sex differences existed, however, concerning singing activity, repertoire size and temporal organisation of song. These results suggest that solo singing in white-browed sparrow weavers is under the control of gonadal steroid hormones. Moreover, the behaviour is not male-specific but can be activated in females under certain conditions. Copyright © 2012 Elsevier Inc. All rights reserved.
Pituitary Androgen Receptor Signalling Regulates Prolactin but Not Gonadotrophins in the Male Mouse
O’Hara, Laura; Curley, Michael; Tedim Ferreira, Maria; Cruickshanks, Lyndsey; Milne, Laura; Smith, Lee B.
2015-01-01
Production of the androgen testosterone is controlled by a negative feedback loop within the hypothalamic-pituitary-gonadal (HPG) axis. Stimulation of testicular Leydig cells by pituitary luteinising hormone (LH) is under the control of hypothalamic gonadotrophin releasing hormone (GnRH), while suppression of LH secretion by the pituitary is controlled by circulating testosterone. Exactly how androgens exert their feedback control of gonadotrophin secretion (and whether this is at the level of the pituitary), as well as the role of AR in other pituitary cell types remains unclear. To investigate these questions, we exploited a transgenic mouse line (Foxg1Cre/+; ARfl/y) which lacks androgen receptor in the pituitary gland. Both circulating testosterone and gonadotrophins are unchanged in adulthood, demonstrating that AR signalling is dispensable in the male mouse pituitary for testosterone-dependent regulation of LH secretion. In contrast, Foxg1Cre/+; ARfl/y males have a significant increase in circulating prolactin, suggesting that, rather than controlling gonadotrophins, AR-signalling in the pituitary acts to suppress aberrant prolactin production in males. PMID:25799562
The effects of sex hormones on immune function: a meta-analysis.
Foo, Yong Zhi; Nakagawa, Shinichi; Rhodes, Gillian; Simmons, Leigh W
2017-02-01
The effects of sex hormones on immune function have received much attention, especially following the proposal of the immunocompetence handicap hypothesis. Many studies, both experimental and correlational, have been conducted to test the relationship between immune function and the sex hormones testosterone in males and oestrogen in females. However, the results are mixed. We conducted four cross-species meta-analyses to investigate the relationship between sex hormones and immune function: (i) the effect of testosterone manipulation on immune function in males, (ii) the correlation between circulating testosterone level and immune function in males, (iii) the effect of oestrogen manipulation on immune function in females, and (iv) the correlation between circulating oestrogen level and immune function in females. The results from the experimental studies showed that testosterone had a medium-sized immunosuppressive effect on immune function. The effect of oestrogen, on the other hand, depended on the immune measure used. Oestrogen suppressed cell-mediated immune function while reducing parasite loads. The overall correlation (meta-analytic relationship) between circulating sex hormone level and immune function was not statistically significant for either testosterone or oestrogen despite the power of meta-analysis. These results suggest that correlational studies have limited value for testing the effects of sex hormones on immune function. We found little evidence of publication bias in the four data sets using indirect tests. There was a weak and positive relationship between year of publication and effect size for experimental studies of testosterone that became non-significant after we controlled for castration and immune measure, suggesting that the temporal trend was due to changes in these moderators over time. Graphical analyses suggest that the temporal trend was due to an increased use of cytokine measures across time. We found substantial heterogeneity in effect sizes, except in correlational studies of testosterone, even after we accounted for the relevant random and fixed factors. In conclusion, our results provide good evidence that testosterone suppresses immune function and that the effect of oestrogen varies depending on the immune measure used. © 2016 Cambridge Philosophical Society.
Gonzales, Rayna J; Ansar, Saema; Duckles, Sue P; Krause, Diana N
2008-01-01
Tissues from males can be regulated by a balance of androgenic and estrogenic effects because of local metabolism of testosterone and expression of relevant steroid hormone receptors. As a critical first step to understanding sex hormone influences in the cerebral circulation of males, we investigated the presence of enzymes that metabolize testosterone to active products and their respective receptors. We found that cerebral blood vessels from male rats express 5α-reductase type 2 and aromatase, enzymes responsible for conversion of testosterone into dihydrotestosterone (DHT) and 17β-estradiol, respectively. Protein levels of these enzymes, however, were not modulated by long-term in vivo hormone treatment. We also showed the presence of receptors for both androgens (AR) and estrogens (ER) from male cerebral vessels. Western blot analysis showed bands corresponding to the full-length AR (110 kDa) and ERα (66 kDa). Long-term in vivo treatment of orchiectomized rats with testosterone or DHT, but not estrogen, increased AR levels in cerebral vessels. In contrast, ERα protein levels were increased after in vivo treatment with estrogen but not testosterone. Fluorescent immunostaining revealed ERα, AR, and 5α-reductase type 2 in both the endothelial and smooth muscle layers of cerebral arteries, whereas aromatase staining was solely localized to the endothelium. Thus, cerebral vessels from males are target tissues for both androgens and estrogen. Furthermore, local metabolism of testosterone might balance opposing androgenic and estrogenic influences on cerebrovascular as well as brain function in males. PMID:17406656
Olatunji, Lawrence A; Usman, Taofeek O; Akinade, Aminat I; Adeyanju, Oluwaseun A; Kim, InKyeom; Soladoye, Ayodele O
2017-12-01
Elevated gestational circulating testosterone has been associated with pathological pregnancies that increase the risk of development of cardiometabolic disorder in later life. We hypothesised that gestational testosterone exposure, in late pregnancy, causes glucose deregulation and atherogenic dyslipidaemia that would be accompanied by high plasminogen activator inhibitor-1 (PAI-1). The study also hypothesise that low-dose spironolactone treatment would ameliorate these effects. Pregnant Wistar rats received vehicle, testosterone (0.5 mg/kg; sc), spironolactone (0.5 mg/kg, po) or testosterone and spironolactone daily between gestational days 15 and 19. Gestational testosterone exposure led to increased HOMA-IR, circulating insulin, testosterone, 1-h post-load glucose, atherogenic dyslipidaemia, PLR, PAI-1 and MDA. However, all these effects, except that of circulating testosterone, were ameliorated by spironolactone. These results demonstrate that low-dose spironolactone ameliorates glucose deregulation and atherogenic dyslipidaemia during elevated gestational testosterone exposure, at least in part, by suppressing elevated PAI-1.
Testosterone supplementation, glucocorticoid milieu and bone homeostasis in the ageing male.
Ajdžanović, Vladimir Z; Filipović, Branko R; Šošić Jurjević, Branka T; Milošević, Verica Lj
2017-08-01
Male ageing is entwined with a continuous fall in free testosterone levels, which contributes to the pathogenesis of bone loss. Glucocorticoid excess, either dependent on the ageing process or iatrogenically induced, was found to additionally impair the bone structure and metabolism. Cautious testosterone supplementation in this respect may positively affect the glucocorticoid milieu and bone homeostasis, while testosterone-induced changes in the glucocorticoid output could serve as a determinant of bone-related therapeutic outcome. Namely, bone mineral content/density, the parameters of trabecular bone structure as well as bone strength are enhanced, serum calcitonin levels tend to increase, while serum osteocalcin, serum parathyroid hormone and urinary calcium decrease, all upon testosterone administration to the ageing male. In parallel, testosterone application decreases glucocorticoid secretion in the animal models of male ageing, while clinical data in this field are still inconsistent. Importantly, a physiological link exists between testosterone-induced changes in glucocorticoid levels and the tendency of bone status improvement in the ageing male. We believe that the assessment of circulating adrenocorticotropic hormone concentrations together with glucocorticoid levels, reflecting the hypothalamic-pituitary-adrenal axis feedback loop operativeness during testosterone supplementation, represents a well-balanced bone-related therapeutic update. © 2017 Société Française de Pharmacologie et de Thérapeutique.
Gershman, Boris; Shui, Irene M; Stampfer, Meir; Platz, Elizabeth A; Gann, Peter H; Sesso, Howard L; DuPre, Natalie; Giovannucci, Edward; Mucci, Lorelei A
2014-04-01
Sex hormones play an important role in the growth and development of the prostate, and low androgen levels have been suggested to carry an adverse prognosis for men with prostate cancer (PCa). To examine the association between prediagnostic circulating sex hormones and lethal PCa in two prospective cohort studies, the Physicians' Health Study (PHS) and the Health Professionals Follow-up Study (HPFS). We included 963 PCa cases (700 HPFS; 263 PHS) that provided prediagnostic blood samples, in 1982 for PHS and in 1993-1995 for HPFS, in which circulating sex hormone levels were assayed. The primary end point was lethal PCa (defined as cancer-specific mortality or development of metastases), and we also assessed total mortality through March 2011. We used Cox proportional hazards models to evaluate the association of prediagnostic sex hormone levels with time from diagnosis to development of lethal PCa or total mortality. PCa cases were followed for a mean of 12.0±4.9 yr after diagnosis. We confirmed 148 cases of lethal PCa and 421 deaths overall. Using Cox proportional hazard models, we found no significant association between quartile of total testosterone, sex hormone binding globulin (SHBG), SHBG-adjusted testosterone, free testosterone, dihydrotestosterone, androstanediol glucuronide, or estradiol and lethal PCa or total mortality. In subset analyses stratified by Gleason score, TNM stage, age, and interval between blood draw and diagnosis, there was also no consistent association between lethal PCa and sex hormone quartile. We found no overall association between prediagnostic circulating sex hormones and lethal PCa or total mortality. Our null results suggest that reverse causation may be responsible in prior studies that noted adverse outcomes for men with low circulating androgens. Copyright © 2013 European Association of Urology. Published by Elsevier B.V. All rights reserved.
Giltay, Erik J; Enter, Dorien; Zitman, Frans G; Penninx, Brenda W J H; van Pelt, Johannes; Spinhoven, Phillip; Roelofs, Karin
2012-03-01
Low circulating levels of testosterone have been associated with major depression, but there is more limited evidence for differences in patients with anxiety disorders. The use of selective serotonin reuptake inhibitors (SSRIs) and other antidepressants is associated with sexual side effects, warranting testing for interactions with testosterone. Data are from 722 male and 1380 female participants of The Netherlands Study of Depression and Anxiety (NESDA), who were recruited from the community, general practice care, and specialized mental health care. Depressive and anxiety diagnoses were assessed using the DSM-IV Composite International Diagnostic Interview. To smooth the episodic secretion, the four morning saliva samples per participant and the two evening samples were pooled before testosterone analysis. Morning median testosterone levels were 25.2 pg/ml in men and 16.2 pg/ml in women, with lower evening levels of 18.2 and 14.1 pg/ml, respectively. Significant determinants of testosterone levels were sex, age, time of the day, use of contraceptives, and smoking status. Female patients with a current (1-month) depressive disorder (effect size 0.29; P=0.002), generalized anxiety disorder (0.25; P=0.01), social phobia (0.30; P<0.001), and agoraphobia without panic disorder (0.30; P=0.02) had lower salivary testosterone levels than female controls. Higher testosterone levels were found in male and female participants using SSRIs than in non-users (effect size 0.26; P<0.001). Salivary testosterone levels are lower in female patients with a depressive disorder, generalized anxiety disorder, social phobia, and agoraphobia as compared to female controls. SSRIs may increase salivary testosterone in men and women. Copyright © 2011 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nagata, Chisato, E-mail: chisato@gifu-u.ac.jp
Background: Exposure to cadmium has been suspected as a risk factor for breast cancer. The present study examined the associations between urinary cadmium levels and circulating sex hormone levels that are linked to breast cancer risk in healthy women. Methods: The study subjects were 396 premenopausal Japanese women who had regular menstrual cycles less than 40 days long and 207 postmenopausal Japanese women. Urinary cadmium was measured using spot urine samples. Plasma estradiol, testosterone, and dehydroepiandrosterone sulfate were measured. Additionally, the follicle-stimulating hormone, luteinizing hormone, and sex hormone-binding globulin were measured for premenopausal women. Results: In premenopausal women, the urinarymore » cadmium level either expressed in μg per liter or per g of urine creatinine was significantly inversely associated with total and free testosterone levels after controlling for age, body mass index, smoking status, alcohol intake, and the phase of the menstrual cycle. Total and free testosterone levels were 14.6% and 15.0% lower, respectively, in women in the highest quartile of urinary cadmium per g creatinine in those in the lowest quartile. In postmenopausal women, the urinary cadmium in μg per liter as well as per g creatinine was significantly inversely associated with the estradiol level after controlling for covariates. The estradiol level was 25.8% lower in women in the highest tertile of urinary cadmium per g creatinine than in those in the lowest tertile. Conclusions: The data suggest inverse associations between urinary cadmium and the plasma estradiol or testosterone level in Japanese women. - Highlights: • Exposure to cadmium has been suspected as a risk factor for breast cancer. • Urinary cadmium and plasma sex-hormone levels were measured in Japanese women. • Urinary cadmium was inversely associated with testosterone in premenopausal women. • Urinary cadmium was inversely associated with estradiol in postmenopausal women.« less
Brosnan, Mark; Walker, Ian
2009-01-01
Of particular interest to studying the etiology of Autistic Spectrum Disorders (ASDs) is the potential for multiple risk factors to combine through non-random mechanisms-assortative mating. Both genetic influences and a high-testosterone prenatal environment have been implicated in the etiology of ASDs, and given that waist-hip ratio (WHR) is indicative of a woman's circulating testosterone level, a man attracted to higher-than-average WHR women is likely to have a higher-than-average prenatal testosterone exposure for their offspring. We show that whereas fathers of children without ASD show a statistically reliable preference for WHRs at the low end of the normal range, indicative of women with low testosterone levels, fathers of children diagnosed with ASD do not consistently show this preference.
Karolczak, Kamil; Konieczna, Lucyna; Kostka, Tomasz; Witas, Piotr J; Soltysik, Bartlomiej; Baczek, Tomasz; Watala, Cezary
2018-05-02
The cardiovascular effects of testosterone and dihydrotestosterone are generally attributed to their modulatory action on lipid and glucose metabolism. However, no ex vivo studies suggest that circulating androgen levels influence the activation and reactivity of blood platelets - one of the main components of the haemostasis system directly involved in atherosclerosis. The levels of testosterone, dihydrotestosterone and oestradiol in plasma from men and women aged from 60 to 65 years were measured by LC-MS; the aim was to identify any potential relationships between sex steroid levels and the markers of platelet activation (surface membrane expression of GPII/IIIa complex and P-selectin) and platelet reactivity in response to arachidonate, collagen or ADP, monitored with whole blood aggregometry and flow cytometry. The results of the ex vivo part of the study indicate that the concentrations of testosterone and its reduced form, dihydrotestosterone are significantly negatively associated with platelet activation and reactivity. These observations were confirmed in an in vitro model: testosterone and dihydrotestosterone significantly inhibited platelet aggregation triggered by arachidonate or collagen. Our findings indicate that testosterone and dihydrotestosterone are significant haemostatic steroids with inhibitory action on blood platelets in older people.
Nestling immunocompetence and testosterone covary with brood size in a songbird.
Naguib, Marc; Riebel, Katharina; Marzal, Alfonso; Gil, Diego
2004-01-01
The social and ecological conditions that individuals experience during early development have marked effects on their developmental trajectory. In songbirds, brood size is a key environmental factor affecting development, and experimental increases in brood size have been shown to have negative effects on growth, condition and fitness. Possible causes of decreased growth in chicks from enlarged broods are nutritional stress, crowding and increased social competition, i.e. environmental factors known to affect adult steroid levels (especially of testosterone and corticosteroids) in mammals and birds. Little, however, is known about environmental effects on steroid synthesis in nestlings. We addressed this question by following the development of zebra finch (Taeniopygia guttata) chicks that were cross-fostered and raised in different brood sizes. In line with previous findings, nestling growth and cell-mediated immunocompetence were negatively affected by brood size. Moreover, nestling testosterone levels covaried with treatment: plasma testosterone increased with experimental brood size. This result provides experimental evidence that levels of circulating testosterone in nestlings can be influenced by their physiological response to environmental conditions. PMID:15255102
Associations between cadmium exposure and circulating levels of sex hormones in postmenopausal women
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Imran; Engström, Annette; Vahter, Marie
Recent epidemiological as well as in vivo and in vitro studies collectively suggest that the metalloestrogen cadmium (Cd) could be a potential risk factor for hormone-related cancers in particularly breast cancer. Assessment of the association between Cd exposure and levels of endogenous sex hormones is of pivotal importance, as increased levels of such have been associated with a higher risk of breast cancer in postmenopausal women. The present study investigated the perceived relationship (multivariable-adjusted linear regression analyses) between Cd exposure [blood Cd (B-Cd) and urinary Cd (U-Cd)], and serum levels of androstenedione, testosterone, estradiol, and sex-hormone binding globulin (SHBG), inmore » 438 postmenopausal Swedish women without hormone replacement therapy (HRT). A significant positive association between B-Cd (median 3.4 nmol/L) and serum testosterone levels, as well as a significant inverse association between B-Cd and serum estradiol levels and with the estradiol/testosterone ratio were encountered. However, U-Cd (median 0.69 nmol/mmol creatinine) was inversely associated with serum estradiol levels only. Our data may suggest that Cd interferes with the levels of testosterone and estradiol in postmenopausal women, which might have implications for breast cancer risk. - Highlights: • Low level cadmium exposure may interfere with the levels of steroid hormones. • Cadmium exposure was associated with increased serum testosterone concentrations. • Cadmium exposure was associated with decreased estradiol/testosterone ratio. • Cadmium exposure may have implications for breast-cancer promotion.« less
Sex differences in athletic performance emerge coinciding with the onset of male puberty.
Handelsman, David J
2017-07-01
Male performance in athletic events begins to exceed that of age-matched females during early adolescence, but the timing of this divergence relative to the onset of male puberty and the rise in circulating testosterone remains poorly defined. This study is a secondary quantitative analysis of four published sources which aimed to define the timing of the gender divergence in athletic performance and relating it to the rise in circulating testosterone due to male puberty. Four data sources reflecting elite swimming and running and jumping track and field events as well as hand-grip strength in nonathletes were analysed to define the age-specific gender differences through adolescence and their relationship to the rising circulating testosterone during male puberty. The onset and tempo of gender divergence were very similar for swimming, running and jumping events as well as the hand-grip strength in nonathletes, and all closely paralleled the rise in circulating testosterone in adolescent boys. The gender divergence in athletic performance begins at the age of 12-13 years and reaches adult plateau in the late teenage years with the timing and tempo closely parallel to the rise in circulating testosterone in boys during puberty. © 2017 John Wiley & Sons Ltd.
Hellmann, Philip; Christiansen, Peter; Johannsen, Trine Holm; Main, Katharina M; Duno, Morten; Juul, Anders
2012-05-01
To describe the natural history of phenotype, growth and gonadal function in patients with partial androgen insensitivity syndrome. Tertiary paediatric endocrine centre. Retrospective evaluation of 14 male patients with partial androgen insensitivity syndrome (PAIS) with verified androgen receptor (AR) mutations. The authors recorded phenotypic characteristics at birth and external masculinisation score (EMS), registered longitudinal growth, circulating levels of testosterone, estradiol, luteinising hormone (LH), follicle-stimulating hormone (FSH), inhibin-B and sex hormone binding globulin (SHBG), in addition to phenotype at postpubertal follow up. The EMS ranged from 5 to 12 in PAIS at birth. Six patients were born with hypospadias and all patients developed gynaecomastia in puberty. Eight of the patients received testosterone treatment. At follow-up penile size was impaired irrespective of EMS at birth, but responded to pubertal androgen therapy in some of the patients. Serum levels of testosterone, estradiol, SHBG and LH, but not FSH and inhibin B, were markedly elevated in puberty. Final height was 181.3 cm (165.7-190.5 cm) corresponding to an SD score of 0.7 (-2.1 to +2.1 SD, n=10). Gynaecomastia and impaired phallic growth are frequently observed in adults with PAIS, but may be ameliorated by androgen therapy. The authors suggest that male patients presenting with gynaecomastia in puberty, and elevated circulating levels of testosterone, estradiol and LH in puberty, but normal FSH, should be suspected of having PAIS and undergo genetic testing for AR mutations.
Enea, C; Boisseau, N; Ottavy, M; Mulliez, J; Millet, C; Ingrand, I; Diaz, V; Dugué, B
2009-06-01
The objective of this study was to ascertain the effects of menstrual cycle, oral contraception, and training status on the exercise-induced changes in circulating DHEA-sulphate and testosterone in young women. Twenty-eight healthy women were assigned to an untrained group (n = 16) or a trained group (n = 12) depending on their training background. The untrained group was composed of nine oral contraceptive users (OC+) and seven eumenorrheic women (OC-). The trained group was composed of OC+ subjects only. All the OC+ subjects were taking the same low-dose oral contraception. Three laboratory sessions were organised in a randomised order: a prolonged exercise test until exhaustion, a short-term exhaustive exercise test, and a control session. Blood specimens were collected before, during and after the exercise tests and at the same time of the day during the control session. Basal circulating testosterone was significantly lower in trained as compared to untrained subjects. In all subjects, the prolonged exhaustive exercise induced a significant increase in circulating DHEA-s and testosterone. The short-term exercise induced a significant increase in circulating DHEA-s in untrained eumenorrheic and in trained OC users only. Menstrual phases in OC- did not influence the responses. It was found that exhaustive physical exercise induced an increase in circulating DHEA-s and testosterone in young women. Oral contraception may limit short-term exercise-induced changes.
Clotfelter, Ethan D; O'Neal, Dawn M; Gaudioso, Jacqueline M; Casto, Joseph M; Parker-Renga, Ian M; Snajdr, Eric A; Duffy, Deborah L; Nolan, Val; Ketterson, Ellen D
2004-08-01
To explore whether selection for testosterone-mediated traits in males might be constrained by costs of higher testosterone to females, we examined the effects of experimental elevation of plasma testosterone on physiological, reproductive, and behavioral parameters in a female songbird, the dark-eyed junco (Junco hyemalis). We used subcutaneous implants to elevate testosterone (T) in captive and free-living female juncos. In captive birds, we measured the effects of high T on body mass, feather molt, and brood patch formation. In the field, we monitored its effects on the timing of egg laying, clutch size, egg size, egg steroid levels, incubation, and nest-defense behavior. Females implanted with testosterone (T-females) had significantly higher circulating levels of testosterone than did control females (C-females). Captive T-females had lower body mass, were less likely to develop brood patches, and delayed feather molt relative to C-females. Among free-living females, the interval between nest completion and appearance of the first egg was longer for T-females than for C-females and egg yolk concentrations of testosterone were higher, but there were no significant differences in estradiol levels, clutch size, or egg size. Incubation and nest defense behavior were also similar between T- and C-females. Our results suggest that selection on males for higher testosterone might initially lead to a correlated response in females producing changes in body mass and feather molt, both of which could be detrimental. Other possible female responses would be delayed onset of reproduction, which might reduce reproductive success, and higher yolk testosterone, which might have either positive or negative effects on offspring development. We found no reason to expect reduced parental behavior by females as a negative fitness consequence of selection for higher testosterone in males.
Quantitative trait loci that control body weight in DDD/Sgn and C57BL/6J inbred mice.
Suto, Jun-Ichi; Kojima, Misaki
2017-02-01
Inbred DDD/Sgn mice are heavier than inbred C57BL/6J mice. In the present study, we performed quantitative trait loci (QTL) mapping for body weight using R/qtl in reciprocal F 2 male populations between the two strains. We identified four significant QTL on Chrs 1, 2, 5, and 17 (proximal region). The DDD/Sgn allele was associated with increased body weight at QTL on Chrs 1 and 5, and the DDD/Sgn allele was associated with decreased body weight at QTL on Chrs 2 and 17. A multiple regression analysis indicated that the detected QTL explain 30.94 % of the body weight variation. Because DDD/Sgn male mice have extremely high levels of circulating testosterone relative to other inbred mouse strains, we performed QTL mapping for plasma testosterone level to examine the effect of testosterone levels on body weight. We identified one suggestive QTL on Chr 5, which overlapped with body weight QTL. The DDD/Sgn allele was associated with increased testosterone level. Thus, we confirmed that there was a genetic basis for the changes in body weight and testosterone levels in male mice. These findings provide insights into the genetic mechanism by which body weight is controlled in male mice.
Effect of Testosterone Treatment on Adipokines and Gut Hormones in Obese Men on a Hypocaloric Diet.
Ng Tang Fui, Mark; Hoermann, Rudolf; Grossmann, Mathis
2017-04-01
In obese men with lowered testosterone levels, testosterone treatment augments diet-associated loss of body fat. 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. Prespecified secondary analysis of a randomized, double-blind, placebo-controlled trial. Tertiary referral center. Obese men (body mass index ≥30 kg/m 2 ) with a repeated total testosterone level ≤12 nmol/L. 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. Between-group differences in leptin, adiponectin, ghrelin, glucagon like peptide-1, gastric inhibitory polypeptide, peptide YY, pancreatic polypeptide, and amylin levels. 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. Testosterone treatment led to reductions in leptin beyond those achieved by diet-associated weight loss. Testosterone treatment may reduce leptin resistance in obese men.
Verheus, Martijn; Peeters, Petra HM; van Noord, Paulus AH; van der Schouw, Yvonne T; Grobbee, Diederick E; van Gils, Carla H
2007-01-01
Background High breast density is associated with increased breast cancer risk. Epidemiologic studies have shown an increase in breast cancer risk in postmenopausal women with high levels of sex steroids. Hence, sex steroids may increase postmenopausal breast cancer risk via an increase of breast density. The objective of the present study was to study the relation between circulating oestrogens and androgens as well as sex hormone binding globulin (SHBG) in relation to breast density. Methods We conducted a cross-sectional study among 775 postmenopausal women, using baseline data of a random sample of the Prospect-EPIC study. Prospect-EPIC is one of two Dutch cohorts participating in the European Prospective Investigation into Cancer and Nutrition, and women were recruited via a breast cancer screening programme. At enrolment a nonfasting blood sample was taken and a mammogram was made. Oestrone, oestradiol, dehydroepiandrosterone sulfate, androstenedione, testosterone and SHBG levels were measured, using double-antibody radioimmunoassays. Concentrations of free oestradiol and free testosterone were calculated from the measured oestradiol, testosterone and SHBG levels Mammographic dense and nondense areas were measured using a semiquantitative computerized method and the percentage breast density was calculated. Mean breast measures for quintiles of hormone or SHBG levels were estimated using linear regression analyses. Results Both oestrogens and testosterone were inversely related with percent breast density, but these relationships disappeared after adjustment for BMI. None of the sex steroids or SHBG was associated with the absolute measure of breast density, the dense area. Conclusion The results of our study do not support the hypothesis that sex steroids increase postmenopausal breast cancer risk via an increase in breast density. PMID:17692133
Neuman-Lee, Lorin; Greives, Timothy; Hopkins, Gareth R; French, Susannah S
2017-03-01
The neuropeptide kisspeptin and its receptor are essential for activation of the hypothalamic-pituitary-gonadal (HPG) axis and regulating reproduction. While the role of kisspeptin in regulating the HPG axis in mammals has been well established, little is known about the functional ability of kisspeptins to activate the HPG axis and associated behavior in non-mammalian species. Here we experimentally examined the effects of kisspeptin on downstream release of testosterone and associated aggression and display behaviors in the side-blotched lizard (Uta stansburiana). We found that exogenous treatment with kisspeptin resulted in an increase in circulating testosterone levels, castration blocked the kisspeptin-induced increase in testosterone, and testosterone levels in kisspeptin-treated animals were positively related to frequency of aggressive behaviors. This evidence provides a clear link between kisspeptin, testosterone, and aggressive behavior in lizards. Thus, it is likely that kisspeptin plays an important role more broadly in non-mammalian systems in the regulation of reproductive physiology and related behaviors. Copyright © 2016 Elsevier Inc. All rights reserved.
Sauter, Edward R; Tichansky, David S; Chervoneva, Inna; Diamandis, Eleftherios P
2002-01-01
Preliminary evidence has associated testosterone and prostate-specific antigen (PSA) with breast cancer. Our objective was to determine whether a) testosterone levels in nipple aspirate fluid (NAF), serum, or breast tissue are associated with breast cancer; b) testosterone levels in serum are associated with levels in NAF; c) PSA in NAF, serum, or breast tissue is associated with breast cancer; and d) serum PSA is associated with NAF PSA levels. We obtained 342 NAF specimens from 171 women by means of a modified breast pump. Additionally, we collected 201 blood samples from 99 women and 51 tissue samples from 41 subjects who underwent surgical resection for suspected disease. Women currently using birth control pills or hormone replacement therapy were excluded from the study. Controlling for age and menopausal status, serum testosterone was significantly increased in women with breast cancer (p = 0.002). NAF and serum testosterone levels were not associated. Neither NAF nor tissue testosterone was associated with breast cancer. Controlling for menopausal status and age, NAF PSA was significantly decreased in women with breast cancer (p < 0.001). We did not find serum PSA to be associated with breast cancer, although we found an indication that, in postmenopausal women, its levels were lower in women with cancer. Serum PSA was associated with NAF PSA in postmenopausal women (p < 0.001). PSA levels in cancerous tissue were significantly lower than in benign breast specimens from subjects without cancer (p = 0.011), whereas levels of PSA in histologically benign specimens from subjects with cancer were intermediate. Our results suggest that serum testosterone is increased and NAF PSA is decreased in women with breast cancer, with PSA expression being higher in normal than in cancerous breast tissues. NAF and serum PSA levels in postmenopausal women are correlated, suggesting that as laboratory assessment of PSA becomes more sensitive, serum PSA may become useful in identifying women with breast cancer. PMID:11882474
Reproductive endocrinology of wild, long-lived raptors.
Blas, Julio; López, Lidia; Tanferna, Alessandro; Sergio, Fabrizio; Hiraldo, Fernando
2010-08-01
The last decades have witnessed a surge of studies analyzing the role of sex hormones on the behavior and ecology of wild bird populations, allowing a more integrated view of the evolution of avian physiology and life histories. Despite a marked progress, field studies show a considerable bias towards research on specific phylogenetic groups, neglecting a significant fraction of the class Aves. Here we analysed changes in the circulating levels of sex steroids in relation to reproductive behaviour in wild black kites (Milvus migrans), a long-lived and socially monogamous Accipitridae raptor. Males and females displayed a single seasonal peak of circulating testosterone (males) and estradiol (females) during pre-laying and laying. Absolute male testosterone levels were low even at the seasonal maximum and remained below detection limits in females. The latter results supports the idea that avian species establishing long-term pair bonds require lower amounts of circulating androgens for reproduction. Circulating progesterone showed a single seasonal peak in females and males, but their timing (during Incubation and Post-brooding respectively) did not overlap. The fact that females black kites perform the majority of incubation and males provide the majority of care to fledglings suggests that progesterone is involved in the expression of parental behaviors. Copyright 2010 Elsevier Inc. All rights reserved.
Relationships among Musical Aptitude, Digit Ratio and Testosterone in Men and Women
Borniger, Jeremy C.; Chaudhry, Adeel; Muehlenbein, Michael P.
2013-01-01
Circulating adult testosterone levels, digit ratio (length of the second finger relative to the fourth finger), and directional asymmetry in digit ratio are considered sexually dimorphic traits in humans. These have been related to spatial abilities in men and women, and because similar brain structures appear to be involved in both spatial and musical abilities, neuroendocrine function may be related to musical as well as spatial cognition. To evaluate relationships among testosterone and musical ability in men and women, saliva samples were collected, testosterone concentrations assessed, and digit ratios calculated using standardized protocols in a sample of university students (N = 61), including both music and non-music majors. Results of Spearman correlations suggest that digit ratio and testosterone levels are statistically related to musical aptitude and performance only within the female sample: A) those females with greater self-reported history of exposure to music (p = 0.016) and instrument proficiency (p = 0.040) scored higher on the Advanced Measures of Music Audiation test, B) those females with higher left hand digit ratio (and perhaps lower fetal testosterone levels) were more highly ranked (p = 0.007) in the orchestra, C) female music students exhibited a trend (p = 0.082) towards higher testosterone levels compared to female non-music students, and D) female music students with higher rank in the orchestra/band had higher testosterone levels (p = 0.003) than lower ranked students. None of these relationships were significant in the male sample, although a lack of statistical power may be one cause. The effects of testosterone are likely a small part of a poorly understood system of biological and environmental stimuli that contribute to musical aptitude. Hormones may play some role in modulating the phenotype of musical ability, and this may be the case for females more so than males. PMID:23520475
Petterborg, L J; West, D A; Rudeen, P K; Ganjam, V K
1991-11-01
Adult male hamsters were maintained under 14 hours of light per day and randomly assigned to groups that received daily afternoon melatonin (25 micrograms) or vehicle injections. Animals from both groups were killed following 4, 8, and 12 weeks of treatment. By 12 weeks, the melatonin-treated hamsters had significant reductions in the weights of the testes and seminal vesicles, serum testosterone levels, and activities did not differ between groups. In a second experiment, hamsters were hypothalamic-preoptic area (HPOA) aromatase activities. Hypothalamic-preoptic area 5 alpha-reductase activities did not differ between groups. In a second experiment, hamsters were again treated with melatonin or vehicle for 12 weeks prior to being killed. After 10 weeks of treatment, groups of melatonin-treated animals received subcutaneous silastic capsules (5, 10, or 20 mm) filled with testosterone. Animals in two other groups were given blank implants or no implants at all. Two weeks later, at autopsy, reproductive organ weights, serum testosterone levels, and HPOA aromatase activities were significantly suppressed by melatonin administration. 5 alpha-Reductase activity in the HPOA was not affected. Hamsters that had been given the 10- and 20-mm testosterone implants exhibited normal seminal vesicle weights and HPOA aromatase activities. These results suggest that melatonin-induced reduction of HPOA aromatase activity is mediated by decreased circulating levels of testosterone.
Association of hair dye use with circulating levels of sex hormones in premenopausal Japanese women.
Nagata, Chisato; Wada, Keiko; Tsuji, Michiko; Hayashi, Makoto; Takeda, Noriyuki; Yasuda, Keigo
2015-10-01
Substances identified as animal carcinogens are no longer used as ingredients of hair dyes. However, hair dyes are diverse groups of chemicals, and certain compounds may affect endogenous sex hormone levels. We examined the association between hair dye use and sex hormone levels among premenopausal women. Study subjects were 431 premenopausal Japanese women who had regular menstrual cycles less than 40 days long. Information on the use of hair dyes or hair bleach, the type of hair coloring used, the duration of use and the frequency of application was collected using a self-administered questionnaire. Fasting plasma samples were obtained to measure estradiol, testosterone, dehydroepiandrosterone sulfate, sex hormone-binding globulin, follicle-stimulating hormone and luteinizing hormone. After controlling for covariates, the mean plasma total testosterone level was about 14% higher in women who had used hair dyes for 10 or more years than that among women who had never used them (P for trend = 0.02). A similar association was observed when the type of hair dye was restricted to permanent hair dyes. A higher frequency of applying non-permanent hair dyes was marginally significantly associated with higher total and free estradiol levels. Data suggest that long-term use of hair dyes may be associated with an increase in circulating testosterone levels. As this is, to our knowledge, the first study examining the association between hair dye use and sex hormone levels, replication of the results is required. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
Vasculogenesis and Diabetic Erectile Dysfunction: How Relevant Is Glycemic Control?
Castela, Angela; Gomes, Pedro; Silvestre, Ricardo; Guardão, Luísa; Leite, Liliana; Chilro, Rui; Rodrigues, Ilda; Vendeira, Pedro; Virag, Ronald; Costa, Carla
2017-01-01
Erectile dysfunction (ED) is a complication of diabetes, condition responsible for causing endothelial dysfunction (EDys) and hampering repair mechanisms. However, scarce information is available linking vasculogenesis mediated by Endothelial Progenitor Cells (EPCs) and diabetes-associated ED. Furthermore, it remains to be elucidated if glycemic control plays a role on EPCs functions, EPCs modulators, and penile vascular health. We evaluated the effects of diabetes and insulin therapy on bone marrow (BM) and circulating EPCs, testosterone, and systemic/penile Stromal Derived Factor-1 alpha (SDF-1α) expression. Male Wistar rats were divided into groups: age-matched controls, 8-weeks streptozotocin-induced type 1 diabetics, and insulin-treated 8-weeks diabetics. EPCs were identified by flow cytometry for CD34/CD133/VEGFR2/CXCR4 antigens. Systemic SDF-1α and testosterone levels were evaluated by ELISA. Penile SDF-1α protein expression was assessed, in experimental and human diabetic cavernosal samples, by immunohistochemical techniques. Diabetic animals presented a reduction of BM-derived EPCs and an increase in putative circulating endothelial cells (CECs) sloughed from vessels wall. These alterations were rescued by insulin therapy. In addition, glycemic control promoted an increase in systemic testosterone and SDF-1α levels, which were significantly decreased in animals with diabetes. SDF-1α protein expression was reduced in experimental and human cavernosal diabetic samples, an effect prevented by insulin in treated animals. Insulin administration rescued the effects of diabetes on BM function, CECs levels, testosterone, and plasmatic/penile SDF-1α protein expression. This emphasizes the importance of glycemic control in the prevention of diabetes-induced systemic and penile EDys, by the amelioration of endothelial damage, and increase in protective pathways. J. Cell. Biochem. 118: 82-91, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Martinez-Arguelles, Daniel B.; Guichard, Theodore; Culty, Martine; Zirkin, Barry R.; Papadopoulos, Vassilios
2011-01-01
We previously reported that in utero exposure of the male fetus to the plasticizer di-(2-ethylhexyl) phthalate (DEHP) resulted in decreased circulating levels of testosterone in the adult without affecting Leydig cell numbers, luteinizing hormone levels, or steroidogenic enzyme expression. Fetal exposure to DEHP resulted in reduced mineralocorticoid receptor (MR; NR3C2) expression in adult Leydig cells. In the present studies, treatment of pregnant Sprague-Dawley dams from Gestational Day 14 until birth with 20, 50, 100, 300, or 750 mg kg−1 day−1 of DEHP resulted in significant sex-specific decreases in serum aldosterone but not corticosterone levels at Postnatal Day 60 (PND60) but not at PND21. There was no effect on circulating levels of potassium, angiotensin II or adrenocorticotropin hormone (ACTH). However, there was reduced expression of AT receptor Agtr1a, Agtr1b, and Agtr2 mRNAs. The mRNA levels of proteins and enzymes implicated in aldosterone biosynthesis were not affected by in utero DEHP treatment except for Cyp11b2, which was decreased at high (≥500 mg kg−1 day−1) doses. The data presented herein, together with our previous observation that aldosterone stimulates testosterone production via an MR-mediated mechanism, suggest that in utero exposure to DEHP causes reduction in both adrenal aldosterone synthesis and MR expression in Leydig cells, leading to reduced testosterone production in the adult. Moreover, these results suggest the existence of a DEHP-sensitive adrenal-testis axis regulating androgen formation. PMID:21389346
Banerjee, Arnab; Anuradha; Mukherjee, Kaustab; Krishna, Amitabh
2014-11-01
The present study evaluates the hypothesis, that glucose is essential for steroidogenesis and inadequate supply of glucose to the testis may be responsible for decline in steroidogenesis in mice during aging. Mice of different age groups (birth, weaning, puberty, reproductively active, and senescence) were utilized for this study. The changes in glucose, glucose transporter (GLUT), and insulin receptor (IR) level in the testis were evaluated and compared with the testicular steroidogenic parameters such as steroidogenic acute regulatory protein (StAR), 3β-hydroxy steroid dehydrogenase (3β-HSD) and circulating testosterone levels. The result showed significant correlation between changes in GLUT 8 and glucose levels with changes in StAR level in the testis and circulating testosterone level in the mice from birth to senescence. Immunohistochemical analysis showed intense immunostaining of GLUT 8 and IR in the interstitial cells, most likely Leydig cells, in testis of pubertal and reproductively active mice suggesting their relevance in steroidogenesis. The in vitro study showed a significant positive correlation between luteinizing hormone (LH)-induced increase in GLUT 8 and StAR (r = 0.82; P < 0.05) proteins level in the testes with increase in testosterone (r = 0.97; P < 0.05) synthesis of reproductively active mice. This study also showed increased release of lactate with increased uptake of glucose by the testis. Further, intra-testicular treatment of 2-deoxy glucose, to reproductively active mice caused a significant decrease in 3β-HSD enzyme activity in the testis. Based on these findings, it may be concluded that the changes in glucose level either directly or indirectly lead to changes in testicular steroidogenesis during aging. © 2014 Wiley Periodicals, Inc.
Free testosterone levels in umbilical-cord blood predict infant head circumference in females.
Whitehouse, Andrew J O; Maybery, Murray T; Hart, Roger; Sloboda, Deborah M; Stanley, Fiona J; Newnham, John P; Hickey, Martha
2010-03-01
Fetal androgens influence fetal growth as well as postnatal neurocognitive ability. However, to our knowledge, no published study has prospectively examined the impact of early-life androgens on infant brain growth. We report the association between circulating fetal androgen levels, measured from umbilical-cord blood at birth, and a proxy measure of brain growth: head circumference. Participants were 82 unselected female infants from a large representative birth cohort (mean gestational age 39.4 wks, SD 1.7). Umbilical-cord blood was obtained at birth and analysed for androgen concentrations (total testosterone, androstenedione, dehyrdroepiandrosterone, and its sulphated metabolite). Head circumference and two other measures of growth - weight (mean 3311.4 g, SD 461.3) and length - were measured within 3 days of birth and again at approximately 1 year of age (mean age 13.1 mo, SD 1.1). Multivariate linear regressions found an inverse association between levels of free testosterone and growth in head circumference (correlation=-.24), even when adjusting for sociodemographic/obstetric covariates and head size at birth. Growth in weight and length could not be predicted by free testosterone concentration. This is the first report of an association between prenatal androgen levels and postnatal growth in head circumference. These findings suggest that early-life androgens may impact brain development during infancy.
Endocrine-disrupting chemicals (EDCs) are exogenous substances released into the environment that can lead to adverse reproductive effects in fish by a number of mechanisms including altering circulating levels of estradiol (E2), testosterone (T) and 11-ketotestosterone (11KT). ...
Immune and hormonal changes following intense military training.
Gomez-Merino, Danielle; Chennaoui, Mounir; Burnat, Pascal; Drogou, Catherine; Guezennec, Charles Yannick
2003-12-01
This study was designed to determine whether the immune and hormonal systems were affected by a 5-day military course following 3 weeks of combat training in a population of 26 male soldiers (mean age, 21 +/- 2 years). The combination of continuous heavy physical activity and sleep deprivation led to energy deficiency. At the beginning of the training program and immediately after the combat course, saliva samples were assayed for secretory immunoglobulin A and plasma samples were assayed for interleukin-6, dehydroepiandrosterone sulfate, prolactin, catecholamines, glucocorticoids, and testosterone. Secretory immunoglobulin A was lower and circulating interleukin-6 was increased by the end of the course, which was attributed to sympathoadrenergic stimulation. Dehydroepiandrosterone sulfate, prolactin, and testosterone levels fell significantly. These results suggest that prolonged and repeated exercise such as that encountered in a military training program induces immune impairment via a decrease in mucosal immunity and a release of interleukin-6 into the circulation. The impaired secretion of dehydroepiandrosterone sulfate and prolactin, two immunomodulatory hormones, was thought to be a response to the chronic stressors. Lowered testosterone reflects a general decrease in steroid synthesis as a consequence of the physical and psychological strain.
Leuprolide acetate-stimulated androgen response during female puberty.
Hernandez, María Isabel; Martinez-Aguayo, Alejandro; Cavada, Gabriel; Avila, Alejandra; Iñiguez, German; Mericq, Veronica
2015-08-01
A physiological increase in androgen levels occurs during adolescence. Measuring androgen concentrations is the best method to distinguish normal evolution processes from hyperandrogenic disorders. The increase in circulating androgens during puberty is inversely associated with insulin sensitivity in normal weight girls. To assess circulating levels of ovarian androgens and anti-Müllerian hormone (AMH) at baseline and after GnRH analogue (GnRH-a) stimulation in normal pubertal girls across different Tanner stages. We also studied the association between this response and insulin sensitivity. Prospective study of healthy girls (6-12 years) from the local community (n = 63). Tanner I (n = 23) subjects were assessed cross-sectionally, and Tanner II girls (n = 40) were evaluated every 6 months until they reached Tanner V. Early morning dehydroepiandrosterone sulphate (DHEA-S), AMH, sex hormone-binding globulin (SHBG), androstenedione, glucose and insulin levels were measured. A GnRH-a test (500 μg/m(2) ; sc) and oral glucose intolerance test (OGTT) were performed. Differences throughout puberty were evaluated. Basal and/or stimulated Testosterone DHEA-S and 17-hydroxyprogesterone (17OHP) were inversely associated with insulin sensitivity (WIBSI) from the beginning of puberty, whereas androstenedione was directly associated with gonadotrophins. AMH was inversely associated with basal and stimulated gonadotrophins and directly with insulin area under the curve (AUC) only in the early stages of puberty. 17OHP and testosterone responsiveness increased significantly during puberty in all subjects, whereas testosterone levels changed less consistently. This pattern of ovarian-steroidogenic response was most evident during mid- and late puberty. Moreover, during late puberty only, basal 17OHP, testosterone and DHEA-S were positively associated with gonadotrophins. In normal nonobese girls born appropriate for gestational age, androgen synthesis was associated with insulin sensitivity in early puberty and with LH only in late puberty. © 2014 John Wiley & Sons Ltd.
Marijuana use and serum testosterone concentrations among U.S. males.
Thistle, J E; Graubard, B I; Braunlin, M; Vesper, H; Trabert, B; Cook, M B; McGlynn, K A
2017-07-01
Marijuana has been reported to have several effects on the male reproductive system. Marijuana has previously been linked to reduced adult testosterone, however, a study in Denmark reported increased testosterone concentrations among marijuana users. This study was performed to estimate the effect of marijuana use on testosterone in U.S. males. Data on serum testosterone, marijuana use, and covariates for 1577 men from the 2011-2012 U.S. National Health and Nutrition Examination Survey (NHANES) were analyzed. Information on marijuana use was collected by a self-administered computer-assisted questionnaire. Serum testosterone was determined using isotope dilution liquid chromatography tandem mass spectrometry. The effects of marijuana use on serum testosterone concentrations were examined by frequency, duration, and recency of use. Adjusted means and 95% confidence intervals (CI) of serum testosterone across levels of marijuana use were estimated using multiple linear regression weighted by the survey weights. The majority (66.2%) of the weighted study population reported ever using marijuana with 26.6% reporting current marijuana use. There was no difference in serum testosterone between ever users (adjusted mean = 3.69 ng/mL, 95% CI: 3.46, 3.93) and never users (adjusted mean = 3.70 ng/mL, 95% CI: 3.45, 3.98) upon multivariable analysis. However, serum testosterone was inversely associated with time since last regular use of marijuana (p-value for trend = 0.02). When restricted to men aged 18-29 years, this relationship strengthened (p-value for trend <0.01), and serum testosterone was also inversely associated with time since last use (p-value for trend <0.01), indicating that recency of use, and not duration or frequency, had the strongest relationship with testosterone levels. Serum testosterone concentrations were higher in men with more recent marijuana use. Studies are needed to determine the extent to which circulating testosterone concentrations mediate the relationship of marijuana use with male reproductive outcomes. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
Carcaillon, Laure; Blanco, Carmen; Alonso-Bouzón, Cristina; Alfaro-Acha, Ana; Garcia-García, Francisco-José; Rodriguez-Mañas, Leocadio
2012-01-01
Background Age-associated decline in testosterone levels represent one of the potential mechanisms involved in the development of frailty. Although this association has been widely reported in older men, very few data are available in women. We studied the association between testosterone and frailty in women and assessed sex differences in this relationship. Methods We used cross-sectional data from the Toledo Study for Healthy Aging, a population-based cohort study of Spanish elderly. Frailty was defined according to Fried's approach. Multivariate odds-ratios (OR) and 95% confidence intervals (CI) associated with total (TT) and free testosterone (FT) levels were estimated using polytomous logistic regression. Results In women, there was a U-shaped relationship between FT levels and frailty (p for FT2 = 0.03). In addition, very low levels of FT were observed in women with ≥4 frailty criteria (age-adjusted geometric means = 0.13 versus 0.37 in subjects with <4 components, p = 0.010). The association of FT with frailty appeared confined to obese women (p-value for interaction = 0.05).In men, the risk of frailty levels linearly decreased with testosterone (adjusted OR for frailty = 2.9 (95%CI, 1.6–5.1) and 1.6 (95%CI, 1.0–2.5), for 1 SD decrease in TT and FT, respectively). TT and FT showed association with most of frailty criteria. No interaction was found with BMI. Conclusion There is a relationship between circulating levels of FT and frailty in older women. This relation seems to be modulated by BMI. The relevance and the nature of the association of FT levels and frailty are sex-specific, suggesting that different biological mechanisms may be involved. PMID:22403651
Travison, Thomas G.; Vesper, Hubert W.; Orwoll, Eric; Wu, Frederick; Kaufman, Jean Marc; Wang, Ying; Lapauw, Bruno; Fiers, Tom; Matsumoto, Alvin M.
2017-01-01
Background: Reference ranges for testosterone are essential for making a diagnosis of hypogonadism in men. Objective: To establish harmonized reference ranges for total testosterone in men that can be applied across laboratories by cross-calibrating assays to a reference method and standard. Population: The 9054 community-dwelling men in cohort studies in the United States and Europe: Framingham Heart Study; European Male Aging Study; Osteoporotic Fractures in Men Study; and Male Sibling Study of Osteoporosis. Methods: Testosterone concentrations in 100 participants in each of the four cohorts were measured using a reference method at Centers for Disease Control and Prevention (CDC). Generalized additive models and Bland-Altman analyses supported the use of normalizing equations for transformation between cohort-specific and CDC values. Normalizing equations, generated using Passing-Bablok regression, were used to generate harmonized values, which were used to derive standardized, age-specific reference ranges. Results: Harmonization procedure reduced intercohort variation between testosterone measurements in men of similar ages. In healthy nonobese men, 19 to 39 years, harmonized 2.5th, 5th, 50th, 95th, and 97.5th percentile values were 264, 303, 531, 852, and 916 ng/dL, respectively. Age-specific harmonized testosterone concentrations in nonobese men were similar across cohorts and greater than in all men. Conclusion: Harmonized normal range in a healthy nonobese population of European and American men, 19 to 39 years, is 264 to 916 ng/dL. A substantial proportion of intercohort variation in testosterone levels is due to assay differences. These data demonstrate the feasibility of generating harmonized reference ranges for testosterone that can be applied to assays, which have been calibrated to a reference method and calibrator. PMID:28324103
Obesity and age as dominant correlates of low testosterone in men irrespective of diabetes status.
Ng Tang Fui, M; Hoermann, R; Cheung, A S; Gianatti, E J; Zajac, J D; Grossmann, M
2013-11-01
Although men with type 2 diabetes (T2D) frequently have lowered testosterone levels, it is not well established whether this is ascribable to the diabetic state per se, or because of other factors, such as obesity. Our objective was to determine the prevalence and correlates of low testosterone in middle-aged men with diabetes. We conducted a cross-sectional study in 240 men including 80 men with type 1 diabetes (T1D), 80 men with T2D and 80 men without diabetes. Prevalence of a total testosterone ≤8 nmol/L was low, occurring in none of the men with T1D, 6.2% of men with T2D and 2.5% of men without diabetes. Men with T1D had higher testosterone levels compared with men without diabetes (p < 0.001), even after adjustment for body mass index (BMI) and age (p < 0.02). While men with T2D had lower testosterone compared with controls (p = 0.03), this was no longer significant when BMI and age were taken into account (p = 0.16). In the entire cohort, TT remained inversely associated with BMI independent of age, sex hormone-binding globulin and diabetic status (p = 0.01), whereas calculated free testosterone (cFT) was independently and inversely associated with age (p < 0.001), but not with BMI (p = 0.47). These results suggest that marked reductions in circulating testosterone are uncommon in middle-aged men with diabetes. Increasing BMI and age are dominant drivers of lowered total and cFT, respectively, independent of the presence or absence of diabetes. © 2013 American Society of Andrology and European Academy of Andrology.
Gynaecomastia complicating the treatment of myeloma.
Large, D. M.; Jones, J. M.; Shalet, S. M.; Scarffe, J. H.; Gibbs, A. C.
1983-01-01
The hormonal mechanisms involved in the development of gynaecomastia accompanying the treatment of multiple myeloma in adult men have been investigated by studying levels of circulating testosterone (T), oestrone (EI), oestradiol (E2), sex-hormone binding globulin (SHBG), prolactin (PRL) and the gonadotrophins LH and FSH, before, during and after development of gynaecomastia in 4 men. These have been compared with 5 closely matched men who did not develop gynaecomastia during similar treatment for myeloma. Levels of circulating T fell, and levels of E1 and E2 rose during treatment periods in all subjects, and the changes were statistically significant in subjects developing gynaecomastia, which resolved as levels of sex steroid returned towards normal following cessation of treatment. We conclude that treatment of adult men for myeloma results in testicular dysfunction with a reduction in circulating T and a rise in circulating oestrogens. These changes are most marked in subjects developing gynaecomastia in whom the normal breast tissue is stimulated by a subtle, transient oestrogen:androgen imbalance in favour of oestrogens. PMID:6409138
Increasing women’s sexual desire: The comparative effectiveness of estrogens and androgens
Cappelletti, Maurand; Wallen, Kim
2016-01-01
Both estradiol and testosterone have been implicated as the steroid critical for modulating women’s sexual desire. By contrast, in all other female mammals only estradiol has been shown to be critical for female sexual motivation and behavior. Pharmaceutical companies have invested heavily in the development of androgen therapies for female sexual desire disorders, but today there are still no FDA approved androgen therapies for women. Nonetheless, testosterone is currently, and frequently, prescribed off-label for the treatment of low sexual desire in women, and the idea of testosterone as a cure-all for female sexual dysfunction remains popular. This paper places the ongoing debate concerning the hormonal modulation of women’s sexual desire within a historical context, and reviews controlled trials of estrogen and/or androgen therapies for low sexual desire in postmenopausal women. These studies demonstrate that estrogen-only therapies that produce periovulatory levels of circulating estradiol increase sexual desire in postmenopausal women. Testosterone at supraphysiological, but not at physiological, levels enhances the effectiveness of low-dose estrogen therapies at increasing women’s sexual desire; however, the mechanism by which supraphysiological testosterone increases women’s sexual desire in combination with an estrogen remains unknown. Because effective therapies require supraphysiological amounts of testosterone, it remains unclear whether endogenous testosterone contributes to the modulation of women’s sexual desire. The likelihood that an androgen-only clinical treatment will meaningfully increase women’s sexual desire is minimal, and the focus of pharmaceutical companies on the development of androgen therapies for the treatment of female sexual desire disorders is likely misplaced. PMID:26589379
Pre-diabetes and serum sex steroid hormones among US men.
Arthur, R; Rohrmann, S; Møller, H; Selvin, E; Dobs, A S; Kanarek, N; Nelson, W; Platz, E A; Van Hemelrijck, M
2017-01-01
Several studies demonstrate a link between diabetes and sex steroid hormones, but the link with pre-diabetes remains elusive. In this study, we hypothesize that pre-diabetes, which is characterised by having impaired fasting glucose and/or impaired glucose tolerance and/or impaired HbA1C, may influence circulating sex steroid hormone concentrations in men. Thus, we investigated whether serum sex steroid hormone concentrations differ between men with and without pre-diabetes. We analyzed data for 1139 men who were aged 20+ years when they participated in the Third National Health and Nutrition Examination Survey. We calculated adjusted geometric mean serum concentrations of total and estimated free testosterone, androstanediol glucuronide, total and estimated free estradiol, and sex hormone-binding globulin (SHBG) in men with and without pre-diabetes. Logistic regression was used to calculate adjusted odds ratios (OR) of lower concentrations of androgens and SHBG, and higher concentrations of estradiol by prediabetes status. Adjusting for age and race/ethnicity, total testosterone concentration was lower among men with (geometric mean: 4.68 ng/mL) than without (5.36 ng/mL, p = 0.01) pre-diabetes. SHBG concentration was also lower in men with (31.67 nmol/L) than without (36.16 nmol/L; p = 0.01) pre-diabetes. Concentrations of the other hormones did not differ between men with and without pre-diabetes. After adjusting for demographic and lifestyle factors, pre-diabetic men had a higher odds of lower testosterone (OR: 2.58; 95% CI: 1.54-4.29), higher free estradiol level (OR: 1.59; 95% CI: 1.14-2.22), and lower SHBG level (OR: 2.27; 95% CI: 1.32-3.92) compared to men without pre-diabetes. These associations were attenuated after adjusting for adiposity (testosterone OR: 1.76; 95% CI 0.95-3.27, free estradiol OR: 1.29, 95% CI: 0.88-1.88, SHBG OR: 1.71; 95% CI 0.88-3.30). Our findings suggest that men with pre-diabetes have lower circulating total testosterone and SHBG and higher free estradiol levels. © 2016 American Society of Andrology and European Academy of Andrology.
Ballantyne, Kaye N; Kayser, Manfred; Grootegoed, J Anton
2012-01-01
Based on DNA analysis of a historical case, the authors describe how a female athlete can be unknowingly confronted with the consequences of a disorder of sex development resulting in hyperandrogenism emerging early in her sports career. In such a situation, it is harmful and confusing to question sex and gender. Exposure to either a low or high level of endogenous testosterone from puberty is a decisive factor with respect to sexual dimorphism of physical performance. Yet, measurement of testosterone is not the means by which questions of an athlete's eligibility to compete with either women or men are resolved. The authors discuss that it might be justifiable to use the circulating testosterone level as an endocrinological parameter, to try to arrive at an objective criterion in evaluating what separates women and men in sports competitions, which could prevent the initiation of complicated, lengthy and damaging sex and gender verification procedures. PMID:21540190
Ballantyne, Kaye N; Kayser, Manfred; Grootegoed, J Anton
2012-06-01
Based on DNA analysis of a historical case, the authors describe how a female athlete can be unknowingly confronted with the consequences of a disorder of sex development resulting in hyperandrogenism emerging early in her sports career. In such a situation, it is harmful and confusing to question sex and gender. Exposure to either a low or high level of endogenous testosterone from puberty is a decisive factor with respect to sexual dimorphism of physical performance. Yet, measurement of testosterone is not the means by which questions of an athlete's eligibility to compete with either women or men are resolved. The authors discuss that it might be justifiable to use the circulating testosterone level as an endocrinological parameter, to try to arrive at an objective criterion in evaluating what separates women and men in sports competitions, which could prevent the initiation of complicated, lengthy and damaging sex and gender verification procedures.
Honest sexual signalling mediated by parasite and testosterone effects on oxidative balance.
Mougeot, Francois; Martínez-Padilla, Jesús; Webster, Lucy M I; Blount, Jonathan D; Pérez-Rodríguez, Lorenzo; Piertney, Stuart B
2009-03-22
Extravagant ornaments evolved to advertise their bearers' quality, the honesty of the signal being ensured by the cost paid to produce or maintain it. The oxidation handicap hypothesis (OHH) proposes that a main cost of testosterone-dependent ornamentation is oxidative stress, a condition whereby the production of reactive oxygen and nitrogen species (ROS/RNS) overwhelms the capacity of antioxidant defences. ROS/RNS are unstable, very reactive by-products of normal metabolic processes that can cause extensive damage to key biomolecules (cellular proteins, lipids and DNA). Oxidative stress has been implicated in the aetiology of many diseases and could link ornamentation and genetic variation in fitness-related traits. We tested the OHH in a free-living bird, the red grouse. We show that elevated testosterone enhanced ornamentation and increased circulating antioxidant levels, but caused oxidative damage. Males with smaller ornaments suffered more oxidative damage than those with larger ornaments when forced to increase testosterone levels, consistent with a handicap mechanism. Parasites depleted antioxidant defences, caused oxidative damage and reduced ornament expression. Oxidative damage extent and the ability of males to increase antioxidant defences also explained the impacts of testosterone and parasites on ornamentation within treatment groups. Because oxidative stress is intimately linked to immune function, parasite resistance and fitness, it provides a reliable currency in the trade-off between individual health and ornamentation. The costs induced by oxidative stress can apply to a wide range of signals, which are testosterone-dependent or coloured by pigments with antioxidant properties.
Honest sexual signalling mediated by parasite and testosterone effects on oxidative balance
Mougeot, Francois; Martínez-Padilla, Jesu´s; Webster, Lucy M.I.; Blount, Jonathan D.; Pérez-Rodríguez, Lorenzo; Piertney, Stuart B.
2008-01-01
Extravagant ornaments evolved to advertise their bearers' quality, the honesty of the signal being ensured by the cost paid to produce or maintain it. The oxidation handicap hypothesis (OHH) proposes that a main cost of testosterone-dependent ornamentation is oxidative stress, a condition whereby the production of reactive oxygen and nitrogen species (ROS/RNS) overwhelms the capacity of antioxidant defences. ROS/RNS are unstable, very reactive by-products of normal metabolic processes that can cause extensive damage to key biomolecules (cellular proteins, lipids and DNA). Oxidative stress has been implicated in the aetiology of many diseases and could link ornamentation and genetic variation in fitness-related traits. We tested the OHH in a free-living bird, the red grouse. We show that elevated testosterone enhanced ornamentation and increased circulating antioxidant levels, but caused oxidative damage. Males with smaller ornaments suffered more oxidative damage than those with larger ornaments when forced to increase testosterone levels, consistent with a handicap mechanism. Parasites depleted antioxidant defences, caused oxidative damage and reduced ornament expression. Oxidative damage extent and the ability of males to increase antioxidant defences also explained the impacts of testosterone and parasites on ornamentation within treatment groups. Because oxidative stress is intimately linked to immune function, parasite resistance and fitness, it provides a reliable currency in the trade-off between individual health and ornamentation. The costs induced by oxidative stress can apply to a wide range of signals, which are testosterone-dependent or coloured by pigments with antioxidant properties. PMID:19129122
Elevated phthalates' exposure in children with constitutional delay of growth and puberty.
Xie, Changming; Zhao, Yan; Gao, Lianlian; Chen, Jiao; Cai, Depei; Zhang, Yunhui
2015-05-15
Phthalates have been proven to be antiandrogenic, which may interfere with the timing of puberty. Children with Constitutional Delay of Growth and Puberty (CDGP) typically display short stature and pubertal delay. This study investigated whether phthalate's exposure was associated with CDGP, and evaluated the potential mediator role of testosterone. In this case-control study, a total of 167 boys, including 57 boys with CDGP (cases) and 110 controls were enrolled. We measured six major phthalate metabolites in urine samples using high-performance liquid chromatography and tandem mass spectrometry (LC-MS/MS). The serum testosterone level was determined by radioimmunoassay. Children in the CDGP group were determined to have significantly elevated urinary phthalates concentration compared with control subjects (total phthalates median: case, 107.00 ng/ml; control, 62.22 ng/ml, p = 0.001). After adjustment for BMI and other confounding factors: mono-n-butyl phthalate (MBP), monoethyl phthalate (MEP) and total phthalate concentrations were significantly negatively associated with serum testosterone level (MBP: β = -45.7, p = 0.017; MEP: β = -31.6, p = 0.022; total phthalates: β = -24.6, p = 0.011); MBP, MEP, mono (2-ethylhexyl) phthalate (MEHP) and total phthalates were significantly associated with CDGP (odds ratio: MBP: 8.30, p = 0.002; MEP: 5.43, p = 0.002; MEHP: 3.83, p = 0.017; total phthalates: 9.09, p = 0.001). Serum testosterone level acted as a mediator of the association between phthalates' exposure and CDGP (p = 0.002) (proportion mediated: 34.4%). In this case-control study, elevated phthalates' level was detected in children with CDGP in Shanghai, China and phthalate level was associated with CDGP, which appeared to be mediated by circulating testosterone level. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Birzniece, Vita; Ho, Ken K Y
2015-10-01
Tamoxifen, a selective estrogen receptor modulator, suppresses GH secretion in women but not in men. It increases testosterone levels in men. As GH and testosterone stimulate fat metabolism, the metabolic consequences of tamoxifen may be greater in women than in men. To determine whether tamoxifen suppresses fat oxidation (Fox) to a greater degree in women than in men. An open-label study of ten healthy postmenopausal women and ten healthy men receiving 2-week treatment with tamoxifen (20 mg/day). GH response to arginine stimulation, serum levels of IGF1, testosterone and LH (men only), sex hormone binding globulin (SHBG) and whole body basal and postprandial Fox. In women, tamoxifen significantly reduced the mean GH response to arginine stimulation (Δ -87%, P<0.05) and circulating IGF1 levels (Δ -23.5±5.4%, P<0.01). Tamoxifen reduced postprandial Fox in women (Δ -34.6±10.3%; P<0.05). In men, tamoxifen did not affect the GH response to arginine stimulation but significantly reduced mean IGF1 levels (Δ -24.8±6.1%, P<0.01). Tamoxifen increased mean testosterone levels (Δ 52±14.2%; P<0.01). Fox was not significantly affected by tamoxifen in men. Tamoxifen attenuated the GH response to stimulation and reduced postprandial Fox in women but not in men. We conclude that at a therapeutic dose, the suppressive effect of tamoxifen on fat metabolism is gender-dependent. Higher testosterone levels may mitigate the suppression of GH secretion and Fox during tamoxifen treatment in men. © 2015 European Society of Endocrinology.
Circulating endothelial cells as marker of endothelial damage in male hypogonadism.
Milardi, Domenico; Grande, Giuseppe; Giampietro, Antonella; Vendittelli, Francesca; Palumbo, Sara; Tartaglione, Linda; Marana, Riccardo; Pontecorvi, Alfredo; de Marinis, Laura; Zuppi, Cecilia; Capoluongo, Ettore
2012-01-01
Testosterone deficiency has become a frequently diagnosed condition in today's society affected by epidemic obesity, and is associated with cardiovascular risk. Recent studies have established the importance of altered vascular endothelium function in cardiovascular disease. The damage to the endothelium might also cause endothelial cell detachment, resulting in increased numbers of circulating endothelial cells (CEC) within the bloodstream. To evaluate whether hypogonadism could modify CEC count in peripheral bloodstream, we investigated peripheral blood CEC count using the CellSearch System, a semiautomatic method to accurately and reliably enumerate CECs, which are sorted based on a CD146(+), CD105(+), DAPI(+), CD45(-) phenotype, in a population of 20 patients with hypogonadism. The control group comprised 10 age- and sex-matched healthy participants. CEC count per milliliter was significantly increased in patients with hypogonadism vs the control group. In the group with hypogonadism, an inverse exponential correlation was present between testosterone levels and CEC count per milliliter. A direct linear correlation was present between waist circumference and CECs and between body mass index and CECs. The regression analysis showed that testosterone was the significant independent determinant of CECs. Our results underline that male hypogonadism is associated with endothelial dysfunction. The correlation between CEC and waist circumference underlines that visceral obesity may be synergically implicated in this regulation. Future studies are required to unveil the mechanisms involved in the pathogenesis of testosterone-induced endothelial disfunction, which may provide novel therapeutic targets to be incorporated in the management of hypogonadism.
McGee, W.K.; Bishop, C.V.; Bahar, A.; Pohl, C.R.; Chang, R.J.; Marshall, J.C.; Pau, F.K.; Stouffer, R.L.; Cameron, J.L.
2012-01-01
BACKGROUND Hyperandrogenemia is associated with several clinical disorders in which both reproductive dysfunction and metabolic changes may coexist [i.e. polycystic ovary syndrome (PCOS), obesity and congenital adrenal hyperplasia]. Moreover, there is growing evidence that the elevated levels of circulating androgens in obese girls may lead to an increased neuroendocrine drive to the reproductive axis, similar to that associated with PCOS. METHODS To test whether androgen exposure in the childhood and adolescent period could lead to pubertal alterations in LH secretory patterns, female rhesus monkeys received subcutaneous testosterone implants prepubertally beginning at 1 year of age, maintaining a 3.7-fold increase (P = 0.001) in circulating testosterone levels over cholesterol-implant controls (n = 6/group) into the post-pubertal period. In early adulthood, pulsatile secretion of LH was measured over 12 h during the early follicular phase of a menstrual cycle, and responsiveness of the pituitary to gonadotrophin-releasing hormone was determined. In addition, ultrasounds were performed to assess ovarian morphology and glucose tolerance testing was performed to assess insulin sensitivity. RESULTS The timing of menarche was similar between groups. Testosterone-treated animals had a significantly greater LH pulse frequency during the early follicular phase compared with controls (P = 0.039) when measured at 5 years of age. There was a larger LH response to GnRH when testosterone-treated animals were 4 years of age (P = 0.042), but not when the animals were 5 years old (P = 0.57). No differences were seen in insulin sensitivity or ovarian morphology, and the groups showed similar rates of ovulation in early adulthood. CONCLUSIONS Exposure to increased levels of androgens over the course of pubertal development appears to trigger physiological changes in the neural drive to the reproductive axis that resemble those of obese hyperandrogenemic girls in early adulthood and are characteristic of PCOS. PMID:22114112
Trumble, Benjamin C; Blackwell, Aaron D; Stieglitz, Jonathan; Thompson, Melissa Emery; Suarez, Ivan Maldonado; Kaplan, Hillard; Gurven, Michael
2016-01-01
Objectives Despite well-known fitness advantages to males who produce and maintain high endogenous testosterone levels, such phenotypes may be costly if testosterone-mediated investment in reproductive effort trade-off against investment in somatic maintenance. Previous studies of androgen-mediated trade-offs in human immune function find mixed results, in part because most studies either focus on a few indicators of immunity, are confounded by phenotypic correlation, or are observational. Here the association between male endogenous testosterone and 13 circulating cytokines are examined before and after ex vivo antigen stimulation with phytohaemagglutinin (PHA) and lipopolysaccharides (LPS) in a high pathogen population of Bolivian forager-horticulturalists. Materials and Methods A Milliplex 13-plex cytokine panel measured cytokine concentration in whole blood samples from 109 Tsimane men aged 40–89 (median=50 years) before and after antigen stimulation with PHA and LPS. Urinary testosterone was measured via enzyme immunoassay; demographic and anthropometric data were collected as part of the Tsimane Health and Life History Project. Results Higher endogenous testosterone was associated with down-regulated responses in all cytokines after PHA stimulation (but significantly in only 2/13 cytokines), controlling for age and body mass index. In contrast, testosterone was not significantly associated with down-regulation of cytokines after LPS stimulation. MANOVAs indicate that men with higher testosterone showed reduced cytokine responses to PHA compared to LPS (p=0.0098). Discussion Endogenous testosterone appears to be immunomodulatory rather than immunosuppressive. Potentially costlier forms of immune activation like those induced by PHA (largely T-cell biased immune activation) are down-regulated in men with higher testosterone, but testosterone has less impact on potentially less costly immune activation following LPS stimulation (largely B-cell mediated immunity). PMID:27465811
Leptin inhibits testosterone secretion from adult rat testis in vitro.
Tena-Sempere, M; Pinilla, L; González, L C; Diéguez, C; Casanueva, F F; Aguilar, E
1999-05-01
Leptin, the product of the ob gene, has emerged recently as a pivotal signal in the regulation of fertility. Although the actions of leptin in the control of reproductive function are thought to be exerted mainly at the hypothalamic level, the potential direct effects of leptin at the pituitary and gonadal level have been poorly characterised. In the present study, we first assessed the ability of leptin to regulate testicular testosterone secretion in vitro. Secondly, we aimed to evaluate whether leptin can modulate basal gonadotrophin and prolactin (PRL) release by incubated hemi-pituitaries from fasted male rats. To attain the first goal, testicular slices from prepubertal and adult rats were incubated with increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Assuming that in vitro testicular responsiveness to leptin may be dependent on the background leptin levels, testicular tissue from both food-deprived and normally-fed animals was used. Furthermore, leptin modulation of stimulated testosterone secretion was evaluated by incubation of testicular samples with different doses of leptin in the presence of 10 IU human chorionic gonadotrophin (hCG). In addition, analysis of leptin actions on pituitary function was carried out using hemi-pituitaries from fasted adult male rats incubated in the presence of increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Serum testosterone levels, and basal and hCG-stimulated testosterone secretion by incubated testicular tissue were significantly decreased by fasting in prepubertal and adult male rats. However, a significant reduction in circulating LH levels was only evident in adult fasted rats. Doses of 10(-9)-10(-7) M leptin had no effect on basal or hCG-stimulated testosterone secretion by testes from prepubertal rats, regardless of the nutritional state of the donor animal. In contrast, leptin significantly decreased basal and hCG-induced testosterone secretion by testes from fasted and fed adult rats. In addition, 10(-9) M leptin inhibited LH and FSH secretion by incubated hemi-pituitaries from fasted adult males, whereas, at all doses tested, it was ineffective in modulating PRL release. Our results show that leptin, depending on the state of sexual maturation, is able to inhibit testosterone secretion acting at the testicular level. Furthermore, the present data suggest that the actions of leptin on the reproductive system are complex and are probably carried out at different levels of the hypothalamic-pituitary-gonadal axis.
Schořálková, Tereza; Kratochvíl, Lukáš; Kubička, Lukáš
2017-03-01
In vertebrates, male-typical sexual behavior (MSB) is largely controlled by gonadal androgens, however, the mechanism of this control is believed to vary among species. During immediate activation MSB is tightly correlated with circulating levels of androgens, while the organization of MSB by a hormonal event at a specific developmental period, early in ontogeny or during puberty, has been postulated in other lineages. Here, we put forward an alternative concept of "temporal organization". Under temporal organization longer exposure to circulating androgens is needed for the onset of MSB, which can continue for a long time after the levels of these hormones drop. We tested this concept through long-term monitoring of MSB in females and castrated males of the leopard gecko (Eublepharis macularius) in response to experimental changes in testosterone levels. Several weeks of elevated testosterone levels were needed for the full expression of MSB in both treatment groups and MSB diminished only slowly and gradually after the supplementation of exogenous testosterone ended. Moreover, despite receiving the same application of the hormone both the progressive onset and the cessation of MSB were significantly slower in experimental females than in castrated males. We suggest that the concept of temporal organization of MSB can parsimoniously explain several earlier discrepancies and debatable conclusions on the apparent variability in the hormonal control of MSB in vertebrates, which were based on behavioral testing at a few subjectively selected time points. We conclude that long-term and continuous behavioral testing after hormonal manipulations is needed to understand the regulation of MSB in vertebrates. Copyright © 2016 Elsevier Inc. All rights reserved.
Yeap, Bu B; Grossmann, Mathis; McLachlan, Robert I; Handelsman, David J; Wittert, Gary A; Conway, Ann J; Stuckey, Bronwyn Ga; Lording, Douglas W; Allan, Carolyn A; Zajac, Jeffrey D; Burger, Henry G
2016-09-05
Part 1 of this position statement dealt with the assessment of male hypogonadism, including the indications for testosterone therapy. This article, Part 2, focuses on treatment and therapeutic considerations for male hypogonadism and identifies key questions for future research. Key points and recommendations are:Excess cardiovascular events have been reported in some but not all studies of older men without pathological hypogonadism who were given testosterone treatment. Additional studies are needed to clarify whether testosterone therapy influences cardiovascular risk.Testosterone is the native hormone that should be replaced in men being treated for pathological hypogonadism. Convenient and cost-effective treatment modalities include depot intramuscular injection and transdermal administration (gel, cream or liquid formulations).Monitoring of testosterone therapy is recommended for efficacy and safety, focusing on ameliorating symptoms, restoring virilisation, avoiding polycythaemia and maintaining or improving bone mineral density.Treatment aims to relieve an individual's symptoms and signs of androgen deficiency by administering standard doses and maintaining circulating testosterone levels within the reference interval for eugonadal men.Evaluation for cardiovascular disease and prostate cancer risks should be undertaken as appropriate for eugonadal men of similar age. Nevertheless, when there is a reasonable possibility of substantive pre-existing prostate disease, digital rectal examination and prostate-specific antigen testing should be performed before commencing testosterone treatment.Changes in management as result of the position statement: Treatment aims to relieve symptoms and signs of androgen deficiency, using convenient and effective formulations of testosterone. Therapy should be monitored for efficacy and safety.
Salonia, Andrea; Pontillo, Marina; Nappi, Rossella E; Zanni, Giuseppe; Fabbri, Fabio; Scavini, Marina; Daverio, Rita; Gallina, Andrea; Rigatti, Patrizio; Bosi, Emanuele; Bonini, Pier Angelo; Montorsi, Francesco
2008-04-01
There is currently neither a clinically useful, reliable and inexpensive assay to measure circulating levels of free testosterone (T) in the range observed in women, nor is there agreement on the serum free T threshold defining hypoandrogenism that is associated with female-impaired sexual function. Following the Clinical and Laboratory Standards Institute guidelines, we generated clinically applicable ranges for circulating androgens during specific phases of the menstrual cycle in a convenience sample of 120 reproductive-aged, regularly cycling healthy European Caucasian women with self-reported normal sexual function. All participants were asked to complete a semistructured interview and fill out a set of validated questionnaires, including the Female Sexual Function Index, the Female Sexual Distress Scale, and the 21-item Beck's Inventory for Depression. Between 8 am and 10 am, a venous blood sample was drawn from each participant during the midfollicular (day 5 to 8), the ovulatory (day 13 to 15), and the midluteal phase (day 19 to 22) of the same menstrual cycle. Serum levels of total and free testosterone, Delta(4)-androstenedione, dehydroepiandrosterone sulphate and sex hormone-binding globulin during the midfollicular, ovulatory and midluteal phase of the same menstrual cycle. Total and free T levels showed significant fluctuations, peaking during the ovulatory phase. No significant variation during the menstrual cycle were observed for Delta(4)-androstenedione and dehydroepiandrosterone sulphate. Despite the careful selection of participants that yielded an homogeneous group of women without sexual disorders, we observed a wide range of distribution for each of the circulating androgens measured in this study. This report provides clinically applicable ranges for androgens throughout the menstrual cycle in reproductive-aged, regularly cycling, young healthy Caucasian European women with self-reported normal sexual function.
Key, T J; Appleby, P N; Reeves, G K; Roddam, A W; Helzlsouer, K J; Alberg, A J; Rollison, D E; Dorgan, J F; Brinton, L A; Overvad, K; Kaaks, R; Trichopoulou, A; Clavel-Chapelon, F; Panico, S; Duell, E J; Peeters, P H M; Rinaldi, S; Fentiman, I S; Dowsett, M; Manjer, J; Lenner, P; Hallmans, G; Baglietto, L; English, D R; Giles, G G; Hopper, J L; Severi, G; Morris, H A; Hankinson, S E; Tworoger, S S; Koenig, K; Zeleniuch-Jacquotte, A; Arslan, A A; Toniolo, P; Shore, R E; Krogh, V; Micheli, A; Berrino, F; Barrett-Connor, E; Laughlin, G A; Kabuto, M; Akiba, S; Stevens, R G; Neriishi, K; Land, C E; Cauley, J A; Lui, Li Yung; Cummings, Steven R; Gunter, M J; Rohan, T E; Strickler, H D
2011-01-01
Background: Breast cancer risk for postmenopausal women is positively associated with circulating concentrations of oestrogens and androgens, but the determinants of these hormones are not well understood. Methods: Cross-sectional analyses of breast cancer risk factors and circulating hormone concentrations in more than 6000 postmenopausal women controls in 13 prospective studies. Results: Concentrations of all hormones were lower in older than younger women, with the largest difference for dehydroepiandrosterone sulphate (DHEAS), whereas sex hormone-binding globulin (SHBG) was higher in the older women. Androgens were lower in women with bilateral ovariectomy than in naturally postmenopausal women, with the largest difference for free testosterone. All hormones were higher in obese than lean women, with the largest difference for free oestradiol, whereas SHBG was lower in obese women. Smokers of 15+ cigarettes per day had higher levels of all hormones than non-smokers, with the largest difference for testosterone. Drinkers of 20+ g alcohol per day had higher levels of all hormones, but lower SHBG, than non-drinkers, with the largest difference for DHEAS. Hormone concentrations were not strongly related to age at menarche, parity, age at first full-term pregnancy or family history of breast cancer. Conclusion: Sex hormone concentrations were strongly associated with several established or suspected risk factors for breast cancer, and may mediate the effects of these factors on breast cancer risk. PMID:21772329
Appleby, Paul N.; Albanes, Demetrius; Black, Amanda; Chan, June M.; Chen, Chu; Cirillo, Piera M.; Cohn, Barbara A.; Cook, Michael B.; Donovan, Jenny L.; Ferrucci, Luigi; Garland, Cedric F.; Giles, Graham G.; Goodman, Phyllis J.; Habel, Laurel A.; Haiman, Christopher A.; Holly, Jeff M. P.; Hoover, Robert N.; Kaaks, Rudolf; Knekt, Paul; Kolonel, Laurence N.; Kubo, Tatsuhiko; Le Marchand, Loïc; Luostarinen, Tapio; MacInnis, Robert J.; Mäenpää, Hanna O.; Männistö, Satu; Metter, E. Jeffrey; Milne, Roger L.; Nomura, Abraham M. Y.; Oliver, Steven E.; Parsons, J. Kellogg; Peeters, Petra H.; Platz, Elizabeth A.; Riboli, Elio; Ricceri, Fulvio; Rinaldi, Sabina; Rissanen, Harri; Sawada, Norie; Schaefer, Catherine A.; Schenk, Jeannette M.; Stanczyk, Frank Z.; Stampfer, Meir; Stattin, Pär; Stenman, Ulf-Håkan; Tjønneland, Anne; Trichopoulou, Antonia; Thompson, Ian M.; Tsugane, Shoichiro; Vatten, Lars; Whittemore, Alice S.; Ziegler, Regina G.
2017-01-01
Introduction Sex hormones have been implicated in the etiology of a number of diseases. To better understand disease etiology and the mechanisms of disease-risk factor associations, this analysis aimed to investigate the associations of anthropometric, sociodemographic and behavioural factors with a range of circulating sex hormones and sex hormone-binding globulin. Methods Statistical analyses of individual participant data from 12,330 male controls aged 25–85 years from 25 studies involved in the Endogenous Hormones Nutritional Biomarkers and Prostate Cancer Collaborative Group. Analysis of variance was used to estimate geometric means adjusted for study and relevant covariates. Results Older age was associated with higher concentrations of sex hormone-binding globulin and dihydrotestosterone and lower concentrations of dehydroepiandrosterone sulfate, free testosterone, androstenedione, androstanediol glucuronide and free estradiol. Higher body mass index was associated with higher concentrations of free estradiol, androstanediol glucuronide, estradiol and estrone and lower concentrations of dihydrotestosterone, testosterone, sex hormone-binding globulin, free testosterone, androstenedione and dehydroepiandrosterone sulfate. Taller height was associated with lower concentrations of androstenedione, testosterone, free testosterone and sex hormone-binding globulin and higher concentrations of androstanediol glucuronide. Current smoking was associated with higher concentrations of androstenedione, sex hormone-binding globulin and testosterone. Alcohol consumption was associated with higher concentrations of dehydroepiandrosterone sulfate, androstenedione and androstanediol glucuronide. East Asians had lower concentrations of androstanediol glucuronide and African Americans had higher concentrations of estrogens. Education and marital status were modestly associated with a small number of hormones. Conclusion Circulating sex hormones in men are strongly associated with age and body mass index, and to a lesser extent with smoking status and alcohol consumption. PMID:29281666
Watts, Eleanor L; Appleby, Paul N; Albanes, Demetrius; Black, Amanda; Chan, June M; Chen, Chu; Cirillo, Piera M; Cohn, Barbara A; Cook, Michael B; Donovan, Jenny L; Ferrucci, Luigi; Garland, Cedric F; Giles, Graham G; Goodman, Phyllis J; Habel, Laurel A; Haiman, Christopher A; Holly, Jeff M P; Hoover, Robert N; Kaaks, Rudolf; Knekt, Paul; Kolonel, Laurence N; Kubo, Tatsuhiko; Le Marchand, Loïc; Luostarinen, Tapio; MacInnis, Robert J; Mäenpää, Hanna O; Männistö, Satu; Metter, E Jeffrey; Milne, Roger L; Nomura, Abraham M Y; Oliver, Steven E; Parsons, J Kellogg; Peeters, Petra H; Platz, Elizabeth A; Riboli, Elio; Ricceri, Fulvio; Rinaldi, Sabina; Rissanen, Harri; Sawada, Norie; Schaefer, Catherine A; Schenk, Jeannette M; Stanczyk, Frank Z; Stampfer, Meir; Stattin, Pär; Stenman, Ulf-Håkan; Tjønneland, Anne; Trichopoulou, Antonia; Thompson, Ian M; Tsugane, Shoichiro; Vatten, Lars; Whittemore, Alice S; Ziegler, Regina G; Allen, Naomi E; Key, Timothy J; Travis, Ruth C
2017-01-01
Sex hormones have been implicated in the etiology of a number of diseases. To better understand disease etiology and the mechanisms of disease-risk factor associations, this analysis aimed to investigate the associations of anthropometric, sociodemographic and behavioural factors with a range of circulating sex hormones and sex hormone-binding globulin. Statistical analyses of individual participant data from 12,330 male controls aged 25-85 years from 25 studies involved in the Endogenous Hormones Nutritional Biomarkers and Prostate Cancer Collaborative Group. Analysis of variance was used to estimate geometric means adjusted for study and relevant covariates. Older age was associated with higher concentrations of sex hormone-binding globulin and dihydrotestosterone and lower concentrations of dehydroepiandrosterone sulfate, free testosterone, androstenedione, androstanediol glucuronide and free estradiol. Higher body mass index was associated with higher concentrations of free estradiol, androstanediol glucuronide, estradiol and estrone and lower concentrations of dihydrotestosterone, testosterone, sex hormone-binding globulin, free testosterone, androstenedione and dehydroepiandrosterone sulfate. Taller height was associated with lower concentrations of androstenedione, testosterone, free testosterone and sex hormone-binding globulin and higher concentrations of androstanediol glucuronide. Current smoking was associated with higher concentrations of androstenedione, sex hormone-binding globulin and testosterone. Alcohol consumption was associated with higher concentrations of dehydroepiandrosterone sulfate, androstenedione and androstanediol glucuronide. East Asians had lower concentrations of androstanediol glucuronide and African Americans had higher concentrations of estrogens. Education and marital status were modestly associated with a small number of hormones. Circulating sex hormones in men are strongly associated with age and body mass index, and to a lesser extent with smoking status and alcohol consumption.
Cavalieri, J; Wang, M
2015-08-01
The aim of this study was to determine the effects in Bos indicus calves of intra-testicular injection of either saline (n=9) or one of two doses of zinc acetate ((ZA1, 57.75mg, n=10, or ZA2, 71.75mg, n=10) or surgical castration (n=9) on circulating concentrations of testostosterone and liveweight. Human chorionic gonadotrophin (hCG, 1500IU) was administered 202 and 525 days after treatment on Day 0 and animals were slaughtered on Day 860. In animals left intact treatment with ZA reduced mean serum concentrations of testosterone (Saline: 5.58±0.79ng/mL, ZA1: 1.28±0.27ng/mL, ZA2: 1.01±0.17ng/mL; P<0.001) and concentrations 48h following administration of hCG. The maximum concentration of testosterone recorded throughout the study in six out of 19 animals treated with ZA was ≤0.21ng/mL. Treatment with ZA did not significantly affect live weights or carcass weights or result in any detectable scrotal lesions. Animals with concentrations of testosterone ≥1.0ng/mL exhibited greater liveweights throughout most of the study and yielded heavier carcass weights (340.9±7.02 versus 309.3±6.17kg, P=0.002). It is concluded that a single, intra-testicular administration of either 57.75mg or 71.75mg of ZA was able to similarly reduce circulating concentrations of testosterone without significantly affecting liveweights or carcass weights. Treatment with ZA can result in variation in circulating concentrations of testosterone which could lead to differences in behaviour, liveweights and carcass characteristics. Copyright © 2015 Elsevier B.V. All rights reserved.
Kitaysky, A.S.; Piatt, John F.; Wingfield, J.C.; Romano, M.
1999-01-01
In this study we examined hormonal responses of Black-legged Kittiwake (Rissa tridactyla) chicks to experimental variations in energy content and nutritional quality (low or high lipid to protein ratio, LPR) of their food. Starting at the age of 10 days, chicks were fed either high or low LPR fish at 30, 50, 70 and 100% of ad libitum energy intake. After 20 days of treatment, chicks were exposed to a standardized acute handling and restraint stress protocol, where a baseline sample was taken immediately after taking a chick from the nest, and three additional blood samples were taken at intervals up to 50 min. Testosterone and corticosterone titres in plasma were measured via radioimmunoassay. We found that baseline testosterone levels were not significantly affected by the experimental treatments. Food-restricted chicks had elevated baseline and acute stress-induced levels of corticosterone compared to chicks fed ad libitum. An elevation of circulating levels of corticosterone in energetically stressed individuals was further magnified by low nutritional quality of food. Baseline and acute stress-induced corticosterone levels of chicks were negatively correlated with their fat reserves. We conclude that the physiological condition of Black-legged Kittiwake chicks can be assessed reliably by measuring circulating levels of corticosterone. We discuss short-and long-term effects of elevated corticosterone secretion in food-stressed nest-bound chicks.
Kitaysky, A.S.; Piatt, John F.; Wingfield, J.C.; Romano, M.
1999-01-01
In this study we examined hormonal responses of Black-legged Kittiwake (Rissa tridactyla) chicks to experimental variations in energy content and nutritional quality (low or high lipid to protein ratio, LPR) of their food. Starting at the age of 10 days, chicks were fed either high or low LPR fish at 30, 50, 70 and 100% of ad libitum energy intake. After 20 days of treatment, chicks were exposed to a standardized acute handling and restraint stress protocol, where a baseline sample was taken immediately after taking a chick from the nest, and three additional blood samples were taken at intervals up to 50 min. Testosterone and corticosterone titres in plasma were measured via radioimmunoassay. We found that baseline testosterone levels were not significantly affected by the experimental treatments. Food-restricted chicks had elevated baseline and acute stress-induced levels of corticosterone compared to chicks fed ad libitum. An elevation of circulating levels of corticosterone in energetically stressed individuals was further magnified by low nutritional quality of food. Baseline and acute stress-induced corticosterone levels of chicks were negatively correlated with their fat reserves. We conclude that the physiological condition of Black-legged Kittiwake chicks can be assessed reliably by measuring circulating levels of corticosterone. We discuss short- and long-term effects of elevated corticosterone secretion in food-stressed nest-bound chicks.
Sex differences and the impact of steroid hormones on the developing human brain.
Neufang, Susanne; Specht, Karsten; Hausmann, Markus; Güntürkün, Onur; Herpertz-Dahlmann, Beate; Fink, Gereon R; Konrad, Kerstin
2009-02-01
Little is known about the hormonal effects of puberty on the anatomy of the developing human brain. In a voxel-based morphometry study, sex-related differences in gray matter (GM) volume were examined in 46 subjects aged 8-15 years. Males had larger GM volumes in the left amygdala, whereas females had larger right striatal and bilateral hippocampal GM volumes than males. Sexually dimorphic areas were related to Tanner stages (TS) of pubertal development and to circulating level of steroid hormones in a subsample of 30 subjects. Regardless of sex, amygdala and hippocampal volumes varied as a function of TS and were associated with circulating testosterone (TEST) levels. By contrast, striatal GM volumes were unrelated to pubertal development and circulating steroid hormones. Whole-brain regression analyses revealed positive associations between circulating estrogen levels and parahippocampal GM volumes as well as between TEST levels and diencephalic brain structures. In addition, a negative association was found between circulating TEST and left parietal GM volumes. These data suggest that GM development in certain brain regions is associated with sexual maturation and that pubertal hormones might have organizational effects on the developing human brain.
How does obesity affect fertility in men - and what are the treatment options?
Stokes, Victoria J; Anderson, Richard A; George, Jyothis T
2015-05-01
Adiposity is associated with reduced fertility in men. The aetiology is multifactorial, with obese men at greater risk of suffering from impaired spermatogenesis, reduced circulating testosterone levels, erectile dysfunction and poor libido. The diagnosis and treatment of reduced fertility observed in obese men therefore requires insight into the underlying pathology, which has hormonal, mechanical and psychosocial aspects. This article summarises the current epidemiological, experimental and clinical trial evidence from the perspective of a practicing clinician. The following conclusions and recommendations can be drawn: Obesity is associated with low serum testosterone concentrations, but treatment with exogenous testosterone is likely to adversely impact on fertility. It is important to discuss this with men prior to initiation of testosterone therapy. Obesity adversely affects sperm concentration and may affect sperm quality. However, whether or not weight loss will correct these factors remain to be established. Oestrogen receptor modulators (and aromatase inhibitors) are unlicensed in the treatment for male hypogonadism and/or infertility. These treatments should hence be considered experimental approach until ongoing clinical trials report their outcomes. © 2014 John Wiley & Sons Ltd.
Hu, Min; Richard, Jennifer Elise; Maliqueo, Manuel; Kokosar, Milana; Fornes, Romina; Benrick, Anna; Jansson, Thomas; Ohlsson, Claes; Wu, Xiaoke; Skibicka, Karolina Patrycja; Stener-Victorin, Elisabet
2015-11-17
During pregnancy, women with polycystic ovary syndrome (PCOS) display high circulating androgen levels that may affect the fetus and increase the risk of mood disorders in offspring. This study investigated whether maternal androgen excess causes anxiety-like behavior in offspring mimicking anxiety disorders in PCOS. The PCOS phenotype was induced in rats following prenatal androgen (PNA) exposure. PNA offspring displayed anxiety-like behavior in the elevated plus maze, which was reversed by flutamide [androgen receptor (AR) blocker] and tamoxifen [selective estrogen receptor (ER) modulator]. Circulating sex steroids did not differ between groups at adult age. The expression of serotonergic and GABAergic genes associated with emotional regulation in the amygdala was consistent with anxiety-like behavior in female, and partly in male PNA offspring. Furthermore, AR expression in amygdala was reduced in female PNA offspring and also in females exposed to testosterone in adult age. To determine whether AR activation in amygdala affects anxiety-like behavior, female rats were given testosterone microinjections into amygdala, which resulted in anxiety-like behavior. Together, these data describe the anxiety-like behavior in PNA offspring and adult females with androgen excess, an impact that seems to occur during fetal life, and is mediated via AR in amygdala, together with changes in ERα, serotonergic, and GABAergic genes in amygdala and hippocampus. The anxiety-like behavior following testosterone microinjections into amygdala demonstrates a key role for AR activation in this brain area. These results suggest that maternal androgen excess may underpin the risk of developing anxiety disorders in daughters and sons of PCOS mothers.
Hu, Min; Richard, Jennifer Elise; Maliqueo, Manuel; Kokosar, Milana; Fornes, Romina; Benrick, Anna; Jansson, Thomas; Ohlsson, Claes; Wu, Xiaoke; Skibicka, Karolina Patrycja; Stener-Victorin, Elisabet
2015-01-01
During pregnancy, women with polycystic ovary syndrome (PCOS) display high circulating androgen levels that may affect the fetus and increase the risk of mood disorders in offspring. This study investigated whether maternal androgen excess causes anxiety-like behavior in offspring mimicking anxiety disorders in PCOS. The PCOS phenotype was induced in rats following prenatal androgen (PNA) exposure. PNA offspring displayed anxiety-like behavior in the elevated plus maze, which was reversed by flutamide [androgen receptor (AR) blocker] and tamoxifen [selective estrogen receptor (ER) modulator]. Circulating sex steroids did not differ between groups at adult age. The expression of serotonergic and GABAergic genes associated with emotional regulation in the amygdala was consistent with anxiety-like behavior in female, and partly in male PNA offspring. Furthermore, AR expression in amygdala was reduced in female PNA offspring and also in females exposed to testosterone in adult age. To determine whether AR activation in amygdala affects anxiety-like behavior, female rats were given testosterone microinjections into amygdala, which resulted in anxiety-like behavior. Together, these data describe the anxiety-like behavior in PNA offspring and adult females with androgen excess, an impact that seems to occur during fetal life, and is mediated via AR in amygdala, together with changes in ERα, serotonergic, and GABAergic genes in amygdala and hippocampus. The anxiety-like behavior following testosterone microinjections into amygdala demonstrates a key role for AR activation in this brain area. These results suggest that maternal androgen excess may underpin the risk of developing anxiety disorders in daughters and sons of PCOS mothers. PMID:26578781
Mukhopadhyay, Keya De; Liu, Zhao; Bandyopadhyay, Abhik; Kirma, Nameer B; Tekmal, Rajeshwar R; Wang, Shui; Sun, Lu-Zhe
2015-01-01
In postmenopausal women, local estrogen produced by adipose stromal cells in the breast is believed to support estrogen receptor alpha (ERα) positive breast cancer cell survival and growth. This raises the question of how the ERα positive metastatic breast cancer cells survive after they enter blood and lymph circulation, where estrogen level is very low in postmenopausal women. In this study, we show that the aromatase expression increased when ERα positive breast cancer cells were cultured in suspension. Furthermore, treatment with the aromatase substrate, testosterone, inhibited suspension culture-induced apoptosis whereas an aromatase inhibitor attenuated the effect of testosterone suggesting that suspended circulating ERα positive breast cancer cells may up-regulate intracrine estrogen activity for survival. Consistent with this notion, a moderate level of ectopic aromatase expression rendered a non-tumorigenic ERα positive breast cancer cell line not only tumorigenic but also metastatic in female nude mice without exogenous estrogen supplementation. The increased malignant phenotype was confirmed to be due to aromatase expression as the growth of orthotopic tumors regressed with systemic administration of an aromatase inhibitor. Thus, our study provides experimental evidence that aromatase plays an important role in the survival of metastatic ERα breast cancer cells by suppressing anoikis.
Androgenic correlates of genetic variation in the gene encoding 5alpha-reductase type 1.
Ellis, Justine A; Panagiotopoulos, Sianna; Akdeniz, Aysel; Jerums, George; Harrap, Stephen B
2005-01-01
Androgens determine male secondary sexual characteristics and influence a variety of metabolic pathways. Circulating levels of androgens are highly heritable; however, the genes involved are largely unknown. The 5alpha-reductase enzymes types 1 and 2 responsible for converting testosterone to the more potent androgen dihydrotestosterone are encoded by the SRD5A1 and SRD5A2 genes, respectively. We performed indirect genetic association studies of SRD5A1 and SRD5A2 and the dihydrotestosterone/testosterone ratio that reflects the activity of 5alpha-reductase in 57 males with type 2 diabetes. We found evidence of significant association between a single nucleotide polymorphism in SRD5A1 and the dihydrotestosterone/testosterone ratio (median 0.10, interquartile range 0.08 vs. median 0.06, interquartile range 0.04, P = 0.009). The polymorphism was not associated with any diabetic phenotypes. These results suggest that functional genetic variants might exist in or around SRD5A1 that affect the activity of the 5alpha-reductase enzyme type 1 and influence androgen levels.
Zapletal, D; Macháček, M; Suchý, P; Straková, E; Vitula, F
2018-06-01
1. The aim of this study was to investigate if male-to-female aggression of common pheasants in the course of the breeding season was related to the concentration of plasma testosterone and/or other biochemical plasma indicators in male pheasants housed in breeding cages. The influence of season on the concentration of testosterone and biochemical indicators was also investigated. 2. Males were divided into non-aggressive and aggressive groups during the breeding season based on ethological evaluation. At the beginning, in the middle and at the end of the breeding season, a blood sample was taken from all males on the same day and the concentration of selected biochemical indicators and the total circulating testosterone in the plasma were determined. 3. Male-to-female aggression during the breeding season of pheasants was not influenced by the total plasma testosterone of males. 4. The concentration of total plasma testosterone in males decreased gradually during the breeding season. 5. Male-to-female aggression of pheasants did not have a significant effect on any of the assessed biochemical indicators. 6. The influence of the breeding season affected the activities of alanine aminotransferase and aspartate aminotransferase as well as the concentrations of glucose, magnesium, potassium and chloride in the blood plasma of cage-housed male pheasants.
Casagrande, Stefania; Pinxten, Rianne; Zaid, Erika; Eens, Marcel
2014-01-01
Despite the appealing hypothesis that carotenoid-based colouration signals oxidative status, evidence supporting the antioxidant function of these pigments is scarce. Recent studies have shown that lutein, the most common carotenoid used by birds, can enhance the expression of non-visual traits, such as birdsong. Nevertheless, the underlying physiological mechanisms remain unclear. In this study we hypothesized that male European starlings (Sturnus vulgaris) fed extra lutein increase their song rate as a consequence of an improved oxidative status. Although birdsong may be especially sensitive to the redox status, this has, to the best of our knowledge, never been tested. Together with the determination of circulating oxidative damage (ROMs, reactive oxygen metabolites), we quantified uric acid, albumin, total proteins, cholesterol, and testosterone, which are physiological parameters potentially sensitive to oxidation and/or related to both carotenoid functions and birdsong expression. We found that the birds fed extra lutein sang more frequently than control birds and showed an increase of albumin and cholesterol together with a decrease of oxidative damage. Moreover, we could show that song rate was associated with high levels of albumin and cholesterol and low levels of oxidative damage, independently from testosterone levels. Our study shows for the first time that song rate honestly signals the oxidative status of males and that dietary lutein is associated with the circulation of albumin and cholesterol in birds, providing a novel insight to the theoretical framework related to the honest signalling of carotenoid-based traits. PMID:25549336
Casagrande, Stefania; Pinxten, Rianne; Zaid, Erika; Eens, Marcel
2014-01-01
Despite the appealing hypothesis that carotenoid-based colouration signals oxidative status, evidence supporting the antioxidant function of these pigments is scarce. Recent studies have shown that lutein, the most common carotenoid used by birds, can enhance the expression of non-visual traits, such as birdsong. Nevertheless, the underlying physiological mechanisms remain unclear. In this study we hypothesized that male European starlings (Sturnus vulgaris) fed extra lutein increase their song rate as a consequence of an improved oxidative status. Although birdsong may be especially sensitive to the redox status, this has, to the best of our knowledge, never been tested. Together with the determination of circulating oxidative damage (ROMs, reactive oxygen metabolites), we quantified uric acid, albumin, total proteins, cholesterol, and testosterone, which are physiological parameters potentially sensitive to oxidation and/or related to both carotenoid functions and birdsong expression. We found that the birds fed extra lutein sang more frequently than control birds and showed an increase of albumin and cholesterol together with a decrease of oxidative damage. Moreover, we could show that song rate was associated with high levels of albumin and cholesterol and low levels of oxidative damage, independently from testosterone levels. Our study shows for the first time that song rate honestly signals the oxidative status of males and that dietary lutein is associated with the circulation of albumin and cholesterol in birds, providing a novel insight to the theoretical framework related to the honest signalling of carotenoid-based traits.
Seibert, Julia; Hysek, Cédric M; Penno, Carlos A; Schmid, Yasmin; Kratschmar, Denise V; Liechti, Matthias E; Odermatt, Alex
2014-01-01
3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') and methylphenidate are widely used psychoactive substances. MDMA primarily enhances serotonergic neurotransmission, and methylphenidate increases dopamine but has no serotonergic effects. Both drugs also increase norepinephrine, resulting in sympathomimetic properties. Here we studied the effects of MDMA and methylphenidate on 24-hour plasma steroid profiles. 16 healthy subjects (8 men, 8 women) were treated with single doses of MDMA (125 mg), methylphenidate (60 mg), MDMA + methylphenidate, and placebo on 4 separate days using a cross-over study design. Cortisol, cortisone, corticosterone, 11-dehydrocorticosterone, aldosterone, 11-deoxycorticosterone, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), androstenedione, and testosterone were repeatedly measured up to 24 h using liquid chromatography-tandem mass spectroscopy. MDMA significantly increased the plasma concentrations of cortisol, corticosterone, 11-dehydrocorticosterone, and 11-deoxycorticosterone and also tended to moderately increase aldosterone levels compared with placebo. MDMA also increased the sum of cortisol + cortisone and the cortisol/cortisone ratio, consistent with an increase in glucocorticoid production. MDMA did not alter the levels of cortisone, DHEA, DHEAS, androstenedione, or testosterone. Methylphenidate did not affect any of the steroid concentrations, and it did not change the effects of MDMA on circulating steroids. In summary, the serotonin releaser MDMA has acute effects on circulating steroids. These effects are not observed after stimulation of the dopamine and norepinephrine systems with methylphenidate. The present findings support the view that serotonin rather than dopamine and norepinephrine mediates the acute pharmacologically induced stimulation of the hypothalamic-pituitary-adrenal axis in the absence of other stressors. © 2014 S. Karger AG, Basel.
Testosterone in women--the clinical significance.
Davis, Susan R; Wahlin-Jacobsen, Sarah
2015-12-01
Testosterone is an essential hormone for women, with physiological actions mediated directly or via aromatisation to oestradiol throughout the body. Despite the crucial role of testosterone and the high circulating concentrations of this hormone relative to oestradiol in women, studies of its action and the effects of testosterone deficiency and replacement in women are scarce. The primary indication for the prescription of testosterone for women is loss of sexual desire, which causes affected women substantial concern. That no formulation has been approved for this purpose has not impeded the widespread use of testosterone by women--either off-label or as compounded therapy. Observational studies indicate that testosterone has favourable cardiovascular effects measured by surrogate outcomes; however, associations between endogenous testosterone and the risk of cardiovascular disease and total mortality, particularly in older women, are yet to be established. Adverse cardiovascular effects have not been seen in studies of transdermal testosterone therapy in women. Clinical trials suggest that exogenous testosterone enhances cognitive performance and improves musculoskeletal health in postmenopausal women. Unmet needs include the availability of approved testosterone formulations for women and studies to elucidate the contribution of testosterone to cardiovascular, cognitive, and musculoskeletal health and the risk of cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.
Li, ChunMei; Takahashi, Shinji; Taneda, Shinji; Furuta, Chie; Watanabe, Gen; Suzuki, Akira K; Taya, Kazuyoshi
2006-06-01
The effects of 3-methyl-4-nitrophenol (PNMC), a component of diesel exhaust, on reproductive function were investigated in adult male Japanese quail. The quail were treated with a single i.m. dose of PNMC (78, 103 or 135 mg/kg body weight), and trunk blood and testes were collected 1, 2 or 4 weeks later. Various levels of testicular atrophy were observed in all groups treated with PNMC. Sperm formation, cloacal gland area, and plasma LH and testosterone concentrations were also reduced in birds with testicular atrophy. To determine the acute effect of PNMC on gonadotrophin from the pituitary, adult male quail were administrated a single i.m. injection of PNMC (25 mg/kg), and plasma concentrations of LH were measured at 1, 3 and 6 h. This dose significantly lowered plasma levels of LH at all three time points. These results suggest that PNMC acts on the hypothalamus-pituitary axis, by reducing circulating LH within a few hours of administration and subsequently reducing testosterone secretion. In addition, in order to investigate the direct effects of PNMC on the secretion of testosterone from testicular cells in quail testes, cultured interstitial cells containing Leydig cells were exposed to PNMC (10(-6), 10(-5) or 10(-4) M) for 4, 8 or 24 h. These quantities of PNMC significantly reduced the secretion of testosterone in a time- and dose-dependent manner. The present findings also suggest a direct effect of PNMC on the testis to reduce testosterone secretion. This study clearly indicates that PNMC induces reproductive toxicity at both the central and testicular levels, and disrupts testicular function in adult male quail.
Kinetics of removal of intravenous testosterone pulses in normal men.
Veldhuis, Johannes D; Keenan, Daniel M; Liu, Peter Y; Takahashi, Paul Y
2010-04-01
Testosterone is secreted into the bloodstream episodically, putatively distributing into total, bioavailable (bio) nonsex hormone-binding globulin (nonSHBG-bound), and free testosterone moieties. The kinetics of total, bio, and free testosterone pulses are unknown. Design Adrenal and gonadal steroidogenesis was blocked pharmacologically, glucocorticoid was replaced, and testosterone was infused in pulses in four distinct doses in 14 healthy men under two different paradigms (a total of 220 testosterone pulses). Testosterone kinetics were assessed by deconvolution analysis of total, free, bioavailable, SHBG-bound, and albumin-bound testosterone concentration-time profiles. Independently of testosterone dose or paradigm, rapid-phase half-lives (min) of total, free, bioavailable, SHBG-bound, and albumin-bound testosterone were comparable at 1.4+/-0.22 min (grand mean+/-S.E.M. of geometric means). Slow-phase testosterone half-lives were highest for SHBG-bound testosterone (32 min) and total testosterone (27 min) with the former exceeding that of free testosterone (18 min), bioavailable testosterone (14 min), and albumin-bound testosterone (18 min; P<0.001). Collective outcomes indicate that i) the rapid phase of testosterone disappearance from point sampling in the circulation is not explained by testosterone dose; ii) SHBG-bound testosterone and total testosterone kinetics are prolonged; and iii) the half-lives of bioavailable, albumin-bound, and free testosterone are short. A frequent-sampling strategy comprising an experimental hormone clamp, estimation of hormone concentrations as bound and free moieties, mimicry of physiological pulses, and deconvolution analysis may have utility in estimating the in vivo kinetics of other hormones, substrates, and metabolites.
USDA-ARS?s Scientific Manuscript database
The objective was to determine the effects of naloxone, an opioid peptide receptor antagonist on circulating concentrations of luteinizing hormone (LH) and testosterone in boars characterized as having high (n = 8) or low libido (n = 8) based on the willingness to mount an artificial sow and allow s...
Endocrine-disrupting chemicals (EDCs) are exogenous substances that can lead to impacts on the reproduction of fish sometimes by altering circulating concentrations of 17â-estradiol (E2), testosterone (T) and 11-ketotestosterone (11-KT). Common methods to measure steroids in pla...
Circulating Sex Hormones and Terminal Duct Lobular Unit Involution of the Normal Breast
Khodr, Zeina G.; Sherman, Mark E.; Pfeiffer, Ruth M.; Gierach, Gretchen L.; Brinton, Louise A.; Falk, Roni T.; Patel, Deesha A.; Linville, Laura M.; Papathomas, Daphne; Clare, Susan E.; Visscher, Daniel W.; Mies, Carolyn; Hewitt, Stephen M.; Storniolo, Anna Maria V.; Rosebrock, Adrian; Caban, Jesus J.; Figueroa, Jonine D.
2014-01-01
Background Terminal duct lobular units (TDLUs) are the predominant source of breast cancers. Lesser degrees of age-related TDLU involution have been associated with increased breast cancer risk, but factors that influence involution are largely unknown. We assessed whether circulating hormones, implicated in breast cancer risk, are associated with levels of TDLU involution using data from the Susan G. Komen Tissue Bank (KTB) at the Indiana University Simon Cancer Center (2009-2011). Methods We evaluated three highly reproducible measures of TDLU involution, using normal breast tissue samples from the KTB (n=390): TDLU counts, median TDLU span, and median acini counts per TDLU. Relative risks (RRs, for continuous measures), odds ratios (ORs, for categorical measures), 95% confidence intervals (CIs), and p-trends were calculated to assess the association between tertiles of estradiol, testosterone, sex hormone-binding globulin (SHBG), progesterone, and prolactin with TDLU measures. All models were stratified by menopausal status and adjusted for confounders. Results Among premenopausal women, higher prolactin levels were associated with higher TDLU counts (RRT3vsT1:1.18, 95% CI: 1.07-1.31; p-trend=0.0005), but higher progesterone was associated with lower TDLU counts (RRT3vsT1: 0.80, 95% CI: 0.72-0.89; p-trend<0.0001). Among postmenopausal women, higher levels of estradiol (RRT3vsT1:1.61, 95% CI: 1.32-1.97; p-trend<0.0001) and testosterone (RRT3vsT1: 1.32, 95% CI: 1.09-1.59; p-trend=0.0043) were associated with higher TDLU counts. Conclusions These data suggest that select hormones may influence breast cancer risk potentially through delaying TDLU involution. Impact Increased understanding of the relationship between circulating markers and TDLU involution may offer new insights into breast carcinogenesis. PMID:25472681
Avgoustinaki, Pavlina D; Mitsopoulou, Effrosyni; Chlouverakis, Gregorios; Triantafillou, Theoni; Venihaki, Maria; Koukouli, Sofia; Margioris, Andrew N
2012-01-01
Sex steroids affect human behavior. The aim of the present study was to determine the associations, if any, between the circulating levels of gonadal and adrenal sex steroids in the mid luteal phase (21st day of a normal menstrual cycle, MC) of young professional women and psychometric parameters as assessed by the Minnesota Multiphasic Personality Inventory (MMPI). Our results are as follows: (a) The metabolic product of activated adrenal and gonadal androgens, 3alpha-diolG, was modestly but significantly associated with the social introversion scale (10-SI) (r=0.36, p<0.05), independently accounting for 13% of its variation across participants (R²=0.13, F(1,45)=6.58, p=0.014). (b) Total testosterone was significantly associated with the paranoia scale (6-Pa) (r=0.27, p<0.05). Multiple regression analyses indicated that 10% of the variability in paranoia scores could be independently explained by total testosterone levels (R²=0.10, F(1,57)=6.23, p=0.016). We were unable to find any association between the circulating androgens and scores on the masculinity-femininity scale (Mf). We were also unable to document any association between the weak adrenal androgens DHEA and DHEA-S and depression in contrast to several published reports. (c) Our data suggest a marginally significant association between progesterone and scores on the 7-Pt (obsessive/compulsive/psychasthenia) scale (r=0.27, p<0.05). However, only 7% of the 7-Pt variance was explained by progesterone (R²=0.071, F(1,50)=3.81, p=0.057). We have found that total testosterone was associated with the paranoia score, the metabolic product of activated androgens, 3alpha-diolG, to social introversion and, finally, progesterone to obsessive-compulsive behavior.
Jeng, Hueiwang Anna; Yu, Liang
2008-06-01
The objective of this study was to assess whether polycyclic aromatic hydrocarbons (PAHs) affect male reproductive functions in vivo. Male reproductive parameters included testis weight, sperm counts and motility, circulating follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. The average body weight, testis weight, and epididymis weight in the exposed group were not significantly lower than that in the control group (p < 0.01). The daily numbers of sperm in the PAH-exposed groups were significantly lower than those in the control group. The motility of sperm in the PAH-exposed groups was significantly less than those in the control group. Plasma LH concentrations increased at the end of the exposure period and continued to increase after post-cessation of exposure to PAHs. Testosterone decreased at the end of the exposure period and increased after post-cessation of exposure. However, the follicle-stimulation hormone level remained relatively stable during the study period. The present study showed that PAHs can compromise sperm functions and alter endocrine hormone levels.
The relationship of urocortin-2 with insulin resistance patients having PCOS.
Temur, Muzaffer; Yılmaz, Özgür; Aksun, Saliha; Calan, Mehmet; Özün Özbay, Pelin; Kumbasar, Serkan; Sever, Erman
2017-02-01
In this study, we aimed to compare the serum urocortin-2 (UCN2) levels in women with polycystic ovary syndrome (PCOS) and healthy women. Thirty-eight patients with PCOS and 41 healthy women were included in the study whose age and BMI matched. The fasting serum glucose, insulin, free testosterone, hs-CRP and UCN2 levels of the all participants were examined. HOMA-IR formula was used in order to calculate the insulin resistance. Circulating UCN2 levels were significantly elevated in women with PCOS compared with controls (142.93 ± 59.48 versus 98.56 ± 65.01 pg/ml, p = 0.002). FBG, serum insulin, hs-CRP and HOMA-IR levels were found to be increased in women with PCOS. There was a positive correlation between UCN2 and free-testosterone in only PCOS group (r = 0.235, p = 0.027). Multivariate logistic regression analyses revealed that the odds ratio for PCOS was 2.31 for patients in the highest quartile of UCN2 compared with those in the lowest quartile (OR = 2.31, 95% CI = 1.88-2.83, p=0.021). Multiple linear regression analysis revealed that HOMA-IR, hs-CRP and free-testosterone independently predicted UCN2 levels (p < 0.05). UCN2 levels were significantly higher in PCOS cases when compared to control group. UCN2 is thought to be effective on pathophysiology of PCOS by paracrine and autocrine pathways.
Red wine and component flavonoids inhibit UGT2B17 in vitro
2012-01-01
Background The metabolism and excretion of the anabolic steroid testosterone occurs by glucuronidation to the conjugate testosterone glucuronide which is then excreted in urine. Alterations in UGT glucuronidation enzyme activity could alter the rate of testosterone excretion and thus its bioavailability. The aim of this study is to investigate if red wine, a common dietary substance, has an inhibitory effect on UGT2B17. Methods Testosterone glucuronidation was assayed using human UGT2B17 supersomes with quantification of unglucuronidated testosterone over time using HPLC with DAD detection. The selected red wine was analyzed using HPLC; and the inhibitory effects of the wine and phenolic components were tested independently in a screening assay. Further analyses were conducted for the strongest inhibitors at physiologically relevant concentrations. Control experiments were conducted to determine the effects of the ethanol on UGT2B17. Results Over the concentration range of 2 to 8%, the red wine sample inhibited the glucuronidation of testosterone by up to 70% over 2 hours. The ethanol content had no significant effect. Three red wine phenolics, identified by HPLC analyses, also inhibited the enzyme by varying amounts in the order of quercetin (72%), caffeic acid (22%) and gallic acid (9%); using a ratio of phenolic:testosterone of 1:2.5. In contrast p-coumaric acid and chlorogenic acid had no effect on the UGT2B17. The most active phenolic was selected for a detailed study at physiologically relevant concentrations, and quercetin maintained inhibitory activity of 20% at 2 μM despite a ten-fold excess of testosterone. Conclusion This study reports that in an in vitro supersome-based assay, the key steroid-metabolizing enzyme UGT2B17 is inhibited by a number of phenolic dietary substances and therefore may reduce the rate of testosterone glucuronidation in vivo. These results highlight the potential interactions of a number of common dietary compounds on testosterone metabolism. Considering the variety of foodstuffs that contain flavonoids, it is feasible that diet can elevate levels of circulating testosterone through reduction in urinary excretion. These results warrant further investigation and extension to a human trial to delineate the health implications. PMID:22958586
Abbott, David H; Barnett, Deborah K; Levine, Jon E; Padmanabhan, Vasantha; Dumesic, Daniel A; Jacoris, Steve; Tarantal, Alice F
2008-01-01
Experimentally induced fetal androgen excess induces polycystic ovary syndrome (PCOS)-like traits in adult female rhesus monkeys. Developmental changes leading to this endocrinopathy are not known. We therefore studied 15 time-mated, gravid female rhesus monkeys with known female fetuses. Nine dams received daily subcutaneous injections of 15 mg testosterone propionate (TP) and six received injections of oil vehicle (controls) from 40 through 80 days of gestation (term 165 [range: ±10] days), and all fetuses were delivered by Cesarean-section using established methods at term. Ultrasound-guided fetal blood sample collection and peripheral venous sample collection of dams and subsequent infants enabled determination of circulating levels of steroid hormones, LH and FSH. TP injections elevated serum testosterone and androstenedione levels in the dams and prenatally androgenized (PA) fetuses. After cessation of TP injections, testosterone levels mostly normalized, while serum androstenedione levels in PA infants were elevated. TP injections did not increase estrogen levels in the dams, PA fetuses and infants, yet conjugated estrogen levels were elevated in the TP-injected dams. Serum levels of LH and FSH were elevated in late gestation PA fetuses, and LH levels were elevated in PA infants. These studies suggest that experimentally-induced fetal androgen excess increases gonadotropin secretion in PA female fetuses and infants, and elevates endogenous androgen levels in PA infants. Thus, in this nonhuman primate model, differential programming of the fetal hypothalamo-pituitary unit with concomitant hyperandrogenism provides evidence to suggest developmental origins of LH and androgen excess in adulthood. PMID:18385445
Favourable metabolic effects of a eucaloric lower-carbohydrate diet in women with PCOS.
Gower, Barbara A; Chandler-Laney, Paula C; Ovalle, Fernando; Goree, Laura Lee; Azziz, Ricardo; Desmond, Renee A; Granger, Wesley M; Goss, Amy M; Bates, G Wright
2013-10-01
Diet-induced reduction in circulating insulin may be an attractive nonpharmacological treatment for women with polycystic ovary syndrome (PCOS) among whom elevated insulin may exacerbate symptoms by stimulating testosterone synthesis. This study was designed to determine whether a modest reduction in dietary carbohydrate (CHO) content affects β-cell responsiveness, serum testosterone concentration and insulin sensitivity in women with PCOS. In a crossover design, two diets ('Standard,' STD, 55:18:27% energy from carbohydrate/protein/fat; lower-carbohydrate, 41:19:40) were provided for 8 weeks in random order with a 4-week washout between. Thirty women with PCOS. β-cell responsiveness assessed as the C-peptide response to glucose during a liquid meal test; insulin sensitivity from insulin and glucose values throughout the test; insulin resistance (HOMA-IR); and total testosterone by immunoassay. Paired t-test indicated that the lower-CHO diet induced significant decreases in basal β-cell response (PhiB), fasting insulin, fasting glucose, HOMA-IR, total testosterone and all cholesterol measures, and significant increases in insulin sensitivity and dynamic ('first-phase') β-cell response. The STD diet induced a decrease in HDL-C and an increase in the total cholesterol-to-HDL-C ratio. Across all data combined, the change in testosterone was positively associated with the changes in fasting insulin, PhiB and insulin AUC (P < 0·05). In women with PCOS, modest reduction in dietary CHO in the context of a weight-maintaining diet has numerous beneficial effects on the metabolic profile that may lead to a decrease in circulating testosterone. © 2013 John Wiley & Sons Ltd.
Shao, Xuan; Liu, Yanlei; Liu, Ming; Wang, Yongqing; Yan, Liying; Wang, Hao; Ma, Liyang; Li, Yu-Xia; Zhao, Yangyu; Wang, Yan-Ling
2017-04-01
Preeclampsia, a multisystem syndrome occurring during mid- to late gestation in humans, is a leading cause of maternal and perinatal morbidity and mortality. Patients usually present with high circulating testosterone and reduced estradiol production, but the mechanisms remain unclear. Revealing the mechanism that modulating the imbalance of testosterone and estradiol in preeclampsia is of great value in understanding the cause of the disease. The placenta is the predominant source of steroid hormone production during gestation, and we observed markedly increased 17β-HSD3 (17β-hydroxysteroid dehydrogenase 3) levels and downregulated aromatase expression, the key enzymes responsible for synthesis of testosterone and estradiol, respectively, in preeclamptic placentas compared with controls. Furthermore, we found a significant upregulation of microRNA (miR)-22 in preeclamptic placentas. In a trophoblast cell line, JEG-3 cells, testosterone repressed the expression of aromatase and estrogen receptor α and the production of estradiol while promoting miR-22 expression. miR-22 directly targeted and inhibited estrogen receptor α expression while indirectly decreasing aromatase expression and estradiol production by interfering with estrogen receptor α signaling. Furthermore, inhibition of miR-22 expression significantly reversed the inhibitory effect of testosterone on de novo estradiol synthesis in human trophoblastic cells. The findings reveal a mechanism underlying the balanced production of androgen and estrogen modulated by miR-22 in the human placenta and provide new insights into the pathogenesis of preeclampsia from the aspect of endocrine regulation. © 2017 American Heart Association, Inc.
Steroid determination in fish plasma using capillary electrophoresis.
Bykova, Liliya; Archer-Hartmann, Stephanie A; Holland, Lisa A; Iwanowicz, Luke R; Blazer, Vicki S
2010-09-01
A capillary separation method that incorporates pH-mediated stacking is employed for the simultaneous determination of circulating steroid hormones in plasma from Perca flavescens (yellow perch) collected from natural aquatic environments. The method can be applied to separate eight steroid standards: progesterone, 17alpha,20beta-dihydroxypregn-4-en-3-one, 17alpha-hydroxyprogesterone, testosterone, estrone, 11-ketotestosterone, ethynyl estradiol, and 17beta-estradiol. Based on screening of plasma, the performance of the analytical method was determined for 17alpha,20beta-dihydroxypregn-4-en-3-one, testosterone, 11-ketotestosterone, and 17beta-estradiol. The within-day reproducibility in migration time for these four steroids in aqueous samples was < or =2%. Steroid quantification was accomplished using a calibration curve obtained with external standards. Plasma samples from fish collected from the Choptank and Severn Rivers, Maryland, USA, stored for up to one year were extracted with ethyl acetate and then further processed with anion exchange and hydrophobic solid phase extraction cartridges. The recovery of testosterone and 17beta-estradiol from yellow perch plasma was 84 and 85%, respectively. Endogenous levels of testosterone ranged from 0.9 to 44 ng/ml, and when detected 17alpha,20beta-dihydroxypregn-4-en-3-one ranged from 5 to 34 ng/ml. The reported values for testosterone correlated well with the immunoassay technique. Endogenous concentrations of 17beta-estradiol were < or =1.7 ng/ml. 11-Ketotestosterone was not quantified because of a suspected interferant. Higher levels of 17alpha,20beta-dihydroxypregn-4-en-3-one were found in male and female fish in which 17beta-estradiol was not detected. Monitoring multiple steroids can provide insight into hormonal fluctuations in fish. Copyright 2010 SETAC.
Steroid determination in fish plasma using capillary electrophoresis
Bykova, L.; Archer-Hartmann, S. A.; Holland, L.A.; Iwanowicz, L.R.; Blazer, V.S.
2010-01-01
A capillary separation method that incorporates pH-mediated stacking is employed for the simultaneous determination of circulating steroid hormones in plasma from Perca flavescens (yellow perch) collected from natural aquatic environments. The method can be applied to separate eight steroid standards: progesterone, 17α,20β-dihydroxypregn-4-en-3-one, 17α-hydroxyprogesterone, testosterone, estrone, 11-ketotestosterone, ethynyl estradiol, and 17β-estradiol. Based on screening of plasma, the performance of the analytical method was determined for 17α,20β-dihydroxypregn-4-en-3-one, testosterone, 11-ketotestosterone, and 17β-estradiol. The within-day reproducibility in migration time for these four steroids in aqueous samples was ≤2%. Steroid quantification was accomplished using a calibration curve obtained with external standards. Plasma samples from fish collected from the Choptank and Severn Rivers, Maryland, USA, stored for up to one year were extracted with ethyl acetate and then further processed with anion exchange and hydrophobic solid phase extraction cartridges. The recovery of testosterone and 17β-estradiol from yellow perch plasma was 84 and 85%, respectively. Endogenous levels of testosterone ranged from 0.9 to 44 ng/ml, and when detected 17α,20β-dihydroxypregn-4-en-3-one ranged from 5 to 34 ng/ml. The reported values for testosterone correlated well with the immunoassay technique. Endogenous concentrations of 17β-estradiol were ≤1.7 ng/ml. 11-Ketotestosterone was not quantified because of a suspected interferant. Higher levels of 17α,20β-dihydroxypregn-4-en-3-one were found in male and female fish in which 17β-estradiol was not detected. Monitoring multiple steroids can provide insight into hormonal fluctuations in fish.
NASA Astrophysics Data System (ADS)
Sepehrimanesh, Masood; Saeb, Mehdi; Nazifi, Saeed; Kazemipour, Nasrin; Jelodar, Gholamali; Saeb, Saeedeh
2014-09-01
This work analyzes the effects of radiofrequency-electromagnetic field (RF-EMF) exposure on the reproductive system of male rats, assessed by measuring circulating levels of FSH, LH, inhibin B, activin B, prolactin, and testosterone. Twenty adult male Sprague-Dawley rats (180 ± 10 g) were exposed to 900 MHz RF-EMF in four equal separated groups. The duration of exposure was 1, 2, and 4 h/day over a period of 30 days and sham-exposed animals were kept under the same environmental conditions as the exposed group except with no RF-EMF exposure. Before the exposure, at 15 and 30 days of exposure, determination of the abovementioned hormone levels was performed using ELISA. At the end of the experiment, FSH and LH values of the long time exposure (LTE) group were significantly higher than the sham-exposed group ( p < 0.05). Serum activin B and prolactin in the LTE group showed significant increase and inhibin B showed significant decrease than sham and short time exposed (STE) groups after 30 days RF-EMF exposure ( p < 0.05). Also, a significant decrease in serum testosterone levels in the LTE group was found compared to short and moderate time exposed (MTE) groups after 30 days RF-EMF exposure ( p < 0.05). Results suggest that reproductive hormone levels are disturbed as a result of RF-EMF exposure and it may possibly affect reproductive functions. However, testosterone and inhibin B concentrations as a fertility marker and spermatogenesis were decreased significantly.
Funasaka, Noriko; Yoshioka, Motoi; Ishibashi, Toshiaki; Tatsukawa, Toshiyuki; Shindo, Hideaki; Takada, Koji; Nakamura, Masayuki; Iwata, Tomohiko; Fujimaru, Kaoru; Tanaka, Taira
2018-04-13
We monitored annual fluctuations of gonadal steroid levels in three sexually mature captive finless porpoises (Neophocaena asiaeorientalis; two males and one female) from two different facilities over 56-91 months. Two animals (one male and one female) were held in an indoor tank with a sunroof (facility A) and the other male was held in an indoor tank without a sunroof (facility B). Water temperatures in both facilities reflected seasonal changes during the study period with a minor difference in the fluctuation pattern. Testosterone levels of the male in facility A were higher from spring to summer every year and exhibited a 12-month cycle. The female showed estrus cycles in 1-month intervals from summer to winter, excluding 2 anestrus years. In contrast, the period of higher testosterone levels of the male in facility B gradually initiated earlier over the years under a constant photoperiod (11.5L:12.5D) and exhibited a 9-month cycle during the first 52 months. After changing the light conditions to a natural photoperiod, its testosterone levels were high from early spring to summer for 3 consecutive years and exhibited a 12-month cycle. Our results showed that under a constant artificial photoperiod, the male in facility B failed to recognize the seasonal changes of a natural external environment, resulting in a 9-month, free-running hormone cycle.
Circulating neuroactive C21- and C19-steroids in young men before and after ejaculation.
Stárka, L; Hill, M; Havlíková, H; Kancheva, L; Sobotka, V
2006-01-01
Twelve neuroactive and neuroprotective steroids, androgens and androgen precursors i.e. 3alpha,17beta-dihydroxy-5alpha-androstane, 3alpha-hydroxy-5alpha-androstan-17-one, 3alpha-hydroxy-5beta-androstan-17-one, androst-5-ene-3beta,17beta-diol, 3beta,17alpha-dihydroxy-pregn-5-en-20-one (17alpha-hydroxy-pregnenolone), 3beta-hydroxy-androst-5-en-17-one (dehydroepiandrosterone, DHEA), testosterone, androst-4-ene-3,17-dione (androstenedione), 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone), 3beta-hydroxy-pregn-5-en-20-one (pregnenolone), 7alpha-hydroxy-DHEA, and 7beta-hydroxy-DHEA were measured using the GC-MS system in young men before and after ejaculation provoked by masturbation. The circulating level of 17alpha-hydroxypregnenolone increased significantly, whereas the other circulating steroids were not changed at all. This fact speaks against the hypothesis that a drop in the level of neuroactive steroids, e.g. allopregnanolone may trigger the orgasm-related increase of oxytocin, reported by other authors.
Marshall, Andrew J; Hohmann, Gottfried
2005-01-01
We collected urine samples from seven male bonobos (Pan paniscus) in the Eyengo community, Lomako Forest, Democratic Republic of Congo, and assayed them for testosterone (T). T levels averaged 525 pmol/mg Cr in adult males, and 309 pmol/mg Cr in subadult males. We collected hormonal and behavioral data during a period of relative social instability following the recent arrival of two immigrant males. In concordance with predictions derived from the challenge hypothesis [Wingfield et al., American Naturalist 136:829-846, 1990], which relates T to levels of reproductive aggression, the alpha male had the highest circulating levels of T. When we removed the two recent immigrant males from the analysis, there was a significant positive correlation between T levels and dominance rank for the long-term resident males (n=5, P=0.001, r2=0.98). These are the first data on T levels in wild bonobos, and the results suggest that further study of the relationship between T levels and social context in this species could inform current models relating hormones and aggression in wild apes. (c) 2005 Wiley-Liss, Inc.
Lance, Valentine A; Elsey, Ruth M; Butterstein, George; Trosclair, Phillip L
2004-01-15
All reptiles studied to date show an increase in circulating corticosterone following capture. This rise in corticosterone has also been shown in a number of instances to result in a decline in reproductive steroids within hours after capture. As a result of these observations it has been considered imperative to collect blood samples as soon as possible after capture to get reliable measures of reproductive hormones. It has been claimed, however, that there is no effect of capture stress on reproductive steroids in juvenile alligators held for 2 h following capture. As we generally reject blood samples that are not collected within 15 min of capture we decided to reinvestigate the effect of short-term capture (2 h) on corticosterone and testosterone in male alligators. Four groups of alligators, ranging in size from 74 to 212 cm total length were captured in a 2-week period in May, the time of year when testosterone levels are highest. Two groups were captured during the day (eight bled at capture and again at 2 h, eight bled at 2 h only) and two at night (10 bled at capture and again at 2 h, 10 bled at 2 h only). Testosterone and corticosterone in alligators bled immediately on capture and at 2 h were not significantly different in the AM and PM samples so the results were combined (Initial bleed: corticosterone, 0.95 +/- 0.09 ng/ml, n=18; testosterone, 6.06 +/- 2.09 ng/ml, n=18. Two-hour bleed: corticosterone 15.68 +/- 1.91, n=18; testosterone, 2.75 +/- 0.79, n=18). Both the increase in corticosterone and the decline in testosterone at 2 h were significant (p<0.05). Corticosterone and testosterone in the alligators sampled only once at 2 h were not significantly different from the 2-h values in alligators sampled twice (corticosterone 15.04 +/- 1.29, n=18; testosterone, 1.85 +/- 0.62, n=18). These results clearly demonstrate that short-term capture stress results in a significant decline in testosterone in male alligators.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vittek, J.; L'Hommedieu, D.G.; Gordon, G.G.
Simple and sensitive direct RIA for determination of salivary testosterone was developed by using RSL NOSOLVEX TM (125 1) kit produced by Radioassay System Laboratories (Carcon, California). In addition, a relationship between salivary and serum free and total testosterone concentrations was studied in randomly selected 45 healthy subjects, 5 females on oral contraceptive pills and 28 hypertensive patients on various treatment regimens. The lowest weight of testosterone detectable by the modified method was equivalent to 1 pg/ml of saliva, taking into account analytical variability. Intra- and interassay coefficients of variation were 5.09 +/- 2.7% and 8.2 +/- 5.9% respectively. Statisticallymore » significant correlations were found between salivary and serum free testosterone (r = 0.97) and salivary and serum total testosterone concentrations (r = 0.70 - 0.87). The exception to this was a group of hypertensive females in which no correlation (r = 0.14) between salivary and total serum testosterone was found. It is also of interest that, while salivary testosterone was significantly increased in subjects taking oral contraceptives and most of the hypertensive patients, the total serum testosterone concentration was in normal range. These findings suggest that the determination of salivary testosterone is a reliable method to detect changes in the concentration of available biologically active hormone in the circulation. 21 references, 4 figures, 1 table.« less
Fortes, Matthew B; Diment, Bethany C; Greeves, Julie P; Casey, Anna; Izard, Rachel; Walsh, Neil P
2011-12-01
The aim of this work was to investigate the effect of a daily mixed nutritional supplement upon body composition, physical performance, and circulating anabolic hormones in soldiers undergoing arduous training. Thirty males received either a habitual diet alone (CON, n = 15) or with the addition of a daily mixed supplement (SUP, n = 15) of ∼5.1 MJ·d⁻¹ during 8 weeks of training. Body composition (DEXA), maximal dynamic lift strength (MDLS), and vertical jump (VJ) were assessed, and resting blood samples were collected before and after training. Blood analysis included insulin-like growth factors (IGF-1, IGF BP-1, and IGF BP-3), testosterone, and cortisol. There were no group differences at baseline. Body mass loss (mean ± SD) (CON 5.0 ± 2.3, SUP 1.6 ± 1.5 kg), lean mass loss (CON 2.0 ± 1.5, SUP 0.7 ± 1.5 kg), and fat mass loss (CON 3.0 ± 1.6, SUP 0.9 ± 1.8 kg) were significantly blunted by SUP. CON experienced significant decrements in MDLS (14%), VJ (10%), and explosive leg power (11%) that were prevented by SUP. Military training significantly reduced circulating IGF-1 (28%), testosterone (19%), and the testosterone:cortisol ratio (24%) with no effect of SUP. Circulating IGF BP-1 concentration and cortisol remained unchanged throughout, although SUP abolished the significant decrease in circulating IGF BP-3 (20%) on CON. In conclusion, a daily mixed nutritional supplement attenuated decreases in body mass and lean mass and prevented the decrease in physical performance during an arduous military training program.
Functional Consequences of Mannose and Asialoglycoprotein Receptor Ablation*
Mi, Yiling; Coonce, Marcy; Fiete, Dorothy; Steirer, Lindsay; Dveksler, Gabriela; Townsend, R. Reid; Baenziger, Jacques U.
2016-01-01
The mannose receptor (ManR, Mrc1) and asialoglycoprotein receptor (ASGR, Asgr1 and Asgr2) are highly abundant endocytic receptors expressed by sinusoidal endothelial cells and parenchymal cells in the liver, respectively. We genetically manipulated either receptor individually or in combination, revealing phenotypic changes in female and male mice associated with changes in circulating levels of many glycoproteins. Both receptors rise and fall in response to progesterone during pregnancy. Thirty percent of Asgr2−/− and 65% of Mrc1−/−Asgr2−/− mice are unable to initiate parturition at the end of pregnancy, whereas Mrc1−/− mice initiate normally. Twenty five percent of Mrc1−/−Asgr2−/− male mice develop priapism when mating due to thrombosis of the penile vein, but neither Mrc1−/− nor Asgr2−/− mice do so. The half-life for luteinizing hormone (LH) clearance increases in Mrc1−/− and Mrc1−/−Asgr2−/− mice but not in Asgr2−/− mice; however, LH and testosterone are elevated in all three knockouts. The ManR clears LH thus regulating testosterone production, whereas the ASGR appears to mediate clearance of an unidentified glycoprotein that increases LH levels. More than 40 circulating glycoproteins are elevated >3.0-fold in pregnant Mrc1−/−Asgr2−/− mice. Pregnancy-specific glycoprotein 23, undetectable in WT mice (<50 ng/ml plasma), reaches levels of 1–10 mg/ml in the plasma of Mrc1−/−Asgr2−/− and Asgr2−/− mice, indicating it is cleared by the ASGR. Elevation of multiple coagulation factors in Mrc1−/−Asgr2−/− mice may account for priapism seen in males. These male and female phenotypic changes underscore the key roles of the ManR and ASGR in controlling circulating levels of numerous glycoproteins critical for regulating reproductive hormones and blood coagulation. PMID:27405760
Sex differences in visuospatial abilities persist during induced hypogonadism
Guerrieri, Gioia M.; Wakim, Paul G.; Keenan, P.A.; Schenkel, Linda A; Berlin, Kate; Gibson, Carolyn J.; Rubinow, David R.; Schmidt, Peter J.
2016-01-01
Background Despite well-established sex differences in the performance on tests of several cognitive domains (e.g., visuospatial ability), few studies in humans have evaluated if these sex differences are evident both in the presence of circulating sex hormones and during sex steroid hormonal suppression. Sex differences identified in the relative absence of circulating levels of estradiol and testosterone suggest that differences in brain structure or function exist independent of current hormonal environment and are more likely a reflection of differing developmental exposures and/or genetic substrates. Objective To evaluate cognitive performance in healthy eugonadal men and women before and again during GnRH agonist-induced hypogonadism. Methods Men (n = 16) and women (n = 15) without medical or psychiatric illness were matched for IQ. Cognitive tests were performed at baseline (when eugonadal) and after 68 weeks of GnRH agonist-induced gonadal suppression. The test batteries included measures of verbal and spatial memory, spatial ability, verbal fluency, motor speed/dexterity, and attention/concentration. Data were analyzed using repeated-measures models. Results During both eugonadism and hypogonadism, men performed significantly better than women on several measures of visuospatial performance including mental rotation, line orientation, Money Road Map, Porteus maze, and complex figure drawing. Although some test performances showed an effect of hormone treatment, the majority of these differences reflected an improved performance during hypogonadism compared with baseline (and probably reflected practice effects). Conclusion The well-documented male advantage in visuospatial performance, which we observed during eugonadal conditions, was maintained in the context of short-term suppression of gonadal function in both men and women. These findings suggest that, in humans, sex differences in visuospatial performance are not merely dependent on differences in the current circulating sex steroid environment. Thus sex differences in visuospatial performance in adulthood could reflect early developmental effects of sex steroid exposure or other environmental exposures differing across the sexes as our data confirm that these differences are independent of circulating estradiol or testosterone levels in men and women. PMID:26719236
Sex differences in visuospatial abilities persist during induced hypogonadism.
Guerrieri, Gioia M; Wakim, Paul G; Keenan, P A; Schenkel, Linda A; Berlin, Kate; Gibson, Carolyn J; Rubinow, David R; Schmidt, Peter J
2016-01-29
Despite well-established sex differences in the performance on tests of several cognitive domains (e.g., visuospatial ability), few studies in humans have evaluated if these sex differences are evident both in the presence of circulating sex hormones and during sex steroid hormonal suppression. Sex differences identified in the relative absence of circulating levels of estradiol and testosterone suggest that differences in brain structure or function exist independent of current hormonal environment and are more likely a reflection of differing developmental exposures and/or genetic substrates. To evaluate cognitive performance in healthy eugonadal men and women before and again during GnRH agonist-induced hypogonadism. Men (n=16) and women (n=15) without medical or psychiatric illness were matched for IQ. Cognitive tests were performed at baseline (when eugonadal) and after 6-8 weeks of GnRH agonist-induced gonadal suppression. The test batteries included measures of verbal and spatial memory, spatial ability, verbal fluency, motor speed/dexterity, and attention/concentration. Data were analyzed using repeated-measures models. During both eugonadism and hypogonadism, men performed significantly better than women on several measures of visuospatial performance including mental rotation, line orientation, Money Road Map, Porteus maze, and complex figure drawing. Although some test performances showed an effect of hormone treatment, the majority of these differences reflected an improved performance during hypogonadism compared with baseline (and probably reflected practice effects). The well-documented male advantage in visuospatial performance, which we observed during eugonadal conditions, was maintained in the context of short-term suppression of gonadal function in both men and women. These findings suggest that, in humans, sex differences in visuospatial performance are not merely dependent on differences in the current circulating sex steroid environment. Thus sex differences in visuospatial performance in adulthood could reflect early developmental effects of sex steroid exposure or other environmental exposures differing across the sexes as our data confirm that these differences are independent of circulating estradiol or testosterone levels in men and women. Published by Elsevier Ltd.
Testosterone, Plumage Colouration and Extra-Pair Paternity in Male North-American Barn Swallows
Eikenaar, Cas; Whitham, Megan; Komdeur, Jan; van der Velde, Marco; Moore, Ignacio T.
2011-01-01
In most monogamous bird species, circulating testosterone concentration in males is elevated around the social female's fertile period. Variation in elevated testosterone concentrations among males may have a considerable impact on fitness. For example, testosterone implants enhance behaviours important for social and extra-pair mate choice. However, little is known about the relationship between natural male testosterone concentration and sexual selection. To investigate this relationship we measured testosterone concentration and sexual signals (ventral plumage colour and tail length), and determined within and extra-pair fertilization success in male North American barn swallows (Hirundo rustica erythrogaster). Dark rusty coloured males had higher testosterone concentrations than drab males. Extra-pair paternity was common (42% and 31% of young in 2009 and 2010, respectively), but neither within- nor extra-pair fertilization success was related to male testosterone concentration. Dark rusty males were less often cuckolded, but did not have higher extra-pair or total fertilization success than drab males. Tail length did not affect within- or extra-pair fertilization success. Our findings suggest that, in North American barn swallows, male testosterone concentration does not play a significant direct role in female mate choice and sexual selection. Possibly plumage colour co-varies with a male behavioural trait, such as aggressiveness, that reduces the chance of cuckoldry. This could also explain why dark males have higher testosterone concentrations than drab males. PMID:21853105
Circulating Hepcidin-25 Is Reduced by Endogenous Estrogen in Humans.
Lehtihet, Mikael; Bonde, Ylva; Beckman, Lena; Berinder, Katarina; Hoybye, Charlotte; Rudling, Mats; Sloan, John H; Konrad, Robert J; Angelin, Bo
2016-01-01
Hepcidin reduces iron absorption by binding to the intestinal iron transporter ferroportin, thereby causing its degradation. Although short-term administration of testosterone or growth hormone (GH) has been reported to decrease circulating hepcidin levels, little is known about how hepcidin is influenced in human endocrine conditions associated with anemia. We used a sensitive and specific dual-monoclonal antibody sandwich immunoassay to measure hepcidin-25 in patients (a) during initiation of in vitro fertilization when endogenous estrogens were elevated vs. suppressed, (b) with GH deficiency before and after 12 months substitution treatment, (c) with hyperthyroidism before and after normalization, and (d) with hyperprolactinemia before and after six months of treatment with a dopamine agonist. In response to a marked stimulation of endogenous estrogen production, median hepcidin levels decreased from 4.85 to 1.43 ng/mL (p < 0.01). Hyperthyroidism, hyperprolactinemia, or GH substitution to GH-deficient patients did not influence serum hepcidin-25 levels. In humans, gonadotropin-stimulated endogenous estrogen markedly decreases circulating hepcidin-25 levels. No clear and stable correlation between iron biomarkers and hepcidin-25 was seen before or after treatment of hyperthyroidism, hyperprolactinemia or growth hormone deficiency.
Circulating Hepcidin-25 Is Reduced by Endogenous Estrogen in Humans
Lehtihet, Mikael; Bonde, Ylva; Beckman, Lena; Berinder, Katarina; Hoybye, Charlotte; Rudling, Mats; Sloan, John H.; Konrad, Robert J.; Angelin, Bo
2016-01-01
Objective Hepcidin reduces iron absorption by binding to the intestinal iron transporter ferroportin, thereby causing its degradation. Although short-term administration of testosterone or growth hormone (GH) has been reported to decrease circulating hepcidin levels, little is known about how hepcidin is influenced in human endocrine conditions associated with anemia. Research design and methods We used a sensitive and specific dual–monoclonal antibody sandwich immunoassay to measure hepcidin-25 in patients (a) during initiation of in vitro fertilization when endogenous estrogens were elevated vs. suppressed, (b) with GH deficiency before and after 12 months substitution treatment, (c) with hyperthyroidism before and after normalization, and (d) with hyperprolactinemia before and after six months of treatment with a dopamine agonist. Results In response to a marked stimulation of endogenous estrogen production, median hepcidin levels decreased from 4.85 to 1.43 ng/mL (p < 0.01). Hyperthyroidism, hyperprolactinemia, or GH substitution to GH-deficient patients did not influence serum hepcidin-25 levels. Conclusions In humans, gonadotropin-stimulated endogenous estrogen markedly decreases circulating hepcidin-25 levels. No clear and stable correlation between iron biomarkers and hepcidin-25 was seen before or after treatment of hyperthyroidism, hyperprolactinemia or growth hormone deficiency. PMID:26866603
Lind, Craig M; Beaupre, Steven J
2015-01-01
Life-history theory predicts that organisms will hedge current reproductive investment against potential costs in terms of survivorship and future fecundity. However, little is known regarding the endocrine mechanisms underlying bet-hedging strategies in free-ranging male vertebrates. We examined the relationships among individual energetic status, steroid hormones, mate search, and reproductive behavior in free-ranging male timber rattlesnakes. Snakes were monitored over four active seasons in order to test two hypotheses: (1) males adjust the amount of time and energy allocated toward reproduction according to the level of individual energy stores, and (2) observed condition-dependent reproductive allocation is associated with circulating concentrations of steroid hormones (testosterone and corticosterone) thought to regulate reproductive behaviors in vertebrates. A positive relationship between body condition and testosterone was observed in both the field and the laboratory. Male mate search effort was positively correlated with both body condition and testosterone. Body condition and testosterone concentrations were negatively related to time allocated toward foraging during the breeding season. A strong effect of year was observed in the analysis of testosterone and search effort, suggesting that multiple environmental factors impact hormone production and reproductive investment. Corticosterone was not related to any measured variable. Therefore, our results did not indicate a clear role of corticosterone in mediating observed relationships between energetic status and behavior. Observed relationships are consistent with the hypothesis that males allocate time and energy toward reproduction according to individual energetic status and that testosterone plays a role in mediating the trade-off between current reproductive investment and residual reproductive value.
Barona, Manuela; Kothari, Radha; Skuse, David; Micali, Nadia
2015-01-01
Recent research investigating the extreme male brain theory of autism spectrum disorders (ASD) has drawn attention to the possibility that autistic type social difficulties may be associated with high prenatal testosterone exposure. This study aims to investigate the association between social communication and emotion recognition difficulties and second to fourth digit ratio (2D:4D) and circulating maternal testosterone during pregnancy in a large community-based cohort: the Avon Longitudinal Study of Parents and Children (ALSPAC). A secondary aim is to investigate possible gender differences in the associations. Data on social communication (Social and Communication Disorders Checklist, N = 7165), emotion recognition (emotional triangles, N = 5844 and diagnostics analysis of non-verbal accuracy, N = 7488) and 2D:4D (second to fourth digit ratio, N = 7159) were collected in childhood and early adolescence from questionnaires and face-to-face assessments. Complete data was available on 3515 children. Maternal circulating testosterone during pregnancy was available in a subsample of 89 children. Males had lower 2D:4D ratios than females [t (3513) = -9.775, p < 0.001]. An association was found between measures of social communication and emotion recognition, and the lowest 10 % of 2D:4D ratios. A significant association was found between maternal circulating testosterone and left hand 2D:4D [OR = 1.65, 95 % CI 1.1-2.4, p < 0.01]. Previous findings on the association between 2D:4D and social communication difficulties were not confirmed. A novel association between an extreme measure of 2D:4D in males suggests threshold effects and warrants replication.
Hong, Mee Young; Seeram, Navindra P.; Heber, David
2008-01-01
Prostate cancer is dependent on circulating testosterone in its early stages and is treatable with radiation and surgery. However, recurrent prostate tumors advance to an androgen-independent state where they progress in the absence of circulating testosterone leading to metastasis and death. During the development of androgen independence, prostate cancer cells are known to increase intracellular testosterone synthesis which maintains cancer cell growth in the absence of significant amounts of circulating testosterone. Overexpression of the androgen receptor (AR) occurs in androgen-independent prostate cancer and has been proposed as another mechanism promoting the development of androgen independence. The LNCaP-AR cell line is engineered to overexpress AR but is otherwise similar to the widely studied LNCaP cell line. We have previously shown that pomegranate extracts inhibit both androgen-dependent and androgen-independent prostate cancer cell growth. In the present study, we examined the effects of pomegranate polyphenols, ellagitannin-rich extract and whole juice extract on the expression of genes for key androgen synthesizing enzymes and the AR. We measured expression of the HSD3B2, AKR1C3 and SRD5A1 genes for the respective androgen synthesizing enzymes in LNCaP, LNCaP-AR, and DU-145 human prostate cancer cells. A two-fold suppression of gene expression was considered statistically significant. Pomegranate polyphenols inhibited gene expression and AR most consistently in the LNCaP-AR cell line (P =.05). Therefore, inhibition by pomegranate polyphenols of gene expression involved in androgen synthesis enzymes and the AR may be of particular importance in androgen-independent prostate cancer cells and the subset of human prostate cancers where AR is upregulated. PMID:18479901
Verma, Rachna; Krishna, Amitabh
2017-01-15
The aim of present study was to evaluate the significance of estradiol (E2) in testicular activities and to find out the mechanism by which E2 regulates spermatogenesis in mice. To achieve this, both in vivo and in vitro effect of Letrozole on testis of adult mice was investigated. Letrozole-induced changes in testicular histology, cell proliferation (proliferating cell nuclear antigen; PCNA), cell survival (B cell lymphoma factor-2; Bcl2), apoptotic (cysteine-aspartic proteases; caspase-3), steroidogenic (side chain cleavage; SCC, 3β-hydroxy steroid dehydrogenase enzyme; 3β HSD, steroidogenic acute regulatory protein; StAR, aromatase and luteinizing hormone receptor; LH-R) markers, glucose level, and rate of expression of glucose transporter (GLUT) 8 and insulin receptor (IR) proteins in the testis along with changes in serum E2 and testosterone (T) levels were evaluated. Letrozole acts on testis and caused significant decrease in E2 synthesis, but increase in testosterone level and showed regressive changes in the spermatogenesis. Letrozole-induced changes in various testicular markers were compared with the changes in serum E2 level. The correlation study showed that decreased circulating E2 level may be responsible for decreased insulin receptor (IR) level in the testis. The decreased effects of insulin inhibited the glucose transport in the testis by suppressing GLUT8. The decreased level of testicular glucose may produce less lactate as energy support to developing germ cells consequently resulting in decreased cell proliferation and cell survival, but increased apoptosis. Thus, Letrozole suppresses spermatogenesis by reducing insulin sensitivity and glucose transport in the testis, but significantly increased testosterone level by promoting gonadotrophin release by decreased E2. Copyright © 2016 Elsevier Inc. All rights reserved.
Pharmacoepidemiology of testosterone: Curbing off-label prescribing.
Handelsman, David J
2017-10-01
To estimate the impact of the first year of new Pharmaceutical Benefits Scheme (PBS) prescribing criteria that dictate eligibility for national health scheme subsidy of testosterone prescribing. Analysis of cumulative PBS data. Retrospective analysis of testosterone prescribing from PBS data. Nil MAIN OUTCOME MEASURES: PBS expenditure analysed by total expenditure, by state, and by product type as well as the age, indication, and prescriber type for new testosterone treatment. Total PBS expenditure continued to exceed $20 million in 2014 before declining from 2015 with changes that were uniform by state and product type. Prior to 2015, over 80% were for men aged over 40 years of age for low circulating testosterone in the absence of reproductive system disorders ("Low T") initiated by GPs. From 2015, these features were markedly reduced without changing the numbers of new prescriptions for pathological reproductive disorders or specialist initiations. The short-term impact of 2015 PBS criteria showed highly effective and well-targeted curbing of off-label testosterone prescribing. The findings indicate that the main driver for the recent upsurge in testosterone prescribing was treatment of middle-aged men for "Low T" initiated by GPs. © 2017 Government of New South Wales. Pharmacoepidemiology & Drug Safety © 2017 John Wiley & Sons Ltd.
Plasma testosterone levels in Alzheimer and Parkinson diseases.
Okun, M S; DeLong, M R; Hanfelt, J; Gearing, M; Levey, A
2004-02-10
Testosterone deficiency, a treatable condition commonly seen in aging men, has been linked to Parkinson disease (PD) and Alzheimer disease (AD). In normal subjects, low testosterone levels are associated with cognitive and neuropsychiatric symptoms, yet the relationship between testosterone levels and cognitive function in PD and AD remains unclear. To examine the relationship of testosterone levels to age and cognitive function in PD and AD. Plasma testosterone levels were determined in men enrolled in a clinical registry of subjects with PD and AD, and neuropsychological testing was performed on subjects who consented. Testosterone levels in men with PD were compared with those in men with AD. In both groups, the relationship between testosterone levels and neuropsychological test scores was analyzed, adjusting for age and education. Linear regression analysis revealed that testosterone levels decreased with age in male PD patients (p < 0.03) and male AD patients (p < 0.07). The rate of decline was similar for the two groups. In PD patients, lower testosterone levels were associated with poorer performance on Trails B Seconds (p < 0.02). There is a similar age-related decline in plasma testosterone levels in men with either PD or AD. Previously described associations between low testosterone levels and frontal lobe dysfunction in normal aged men, together with these results, suggest that the hormonal deficiency may act as a "second hit" to impair cognitive function in neurodegenerative disease.
Gustavson, Lisa; Ciesielski, Tomasz M; Bytingsvik, Jenny; Styrishave, Bjarne; Hansen, Martin; Lie, Elisabeth; Aars, Jon; Jenssen, Bjørn M
2015-04-01
As a top predator in the Arctic food chain, polar bears (Ursus maritimus) are exposed to high levels of persistent organic pollutants (POPs). Because several of these compounds have been reported to alter endocrine pathways, such as the steroidogenesis, potential disruption of the sex steroid synthesis by POPs may cause implications for reproduction by interfering with ovulation, implantation and fertility. Blood samples were collected from 15 female polar bears in Svalbard (Norway) in April 2008. The concentrations of nine circulating steroid hormones; dehydroepiandrosterone (DHEA), androstenedione (AN), testosterone (TS), dihydrotestosterone (DHT), estrone (E1), 17α-estradiol (αE2), 17β-estradiol (βE2), pregnenolone (PRE) and progesterone (PRO) were determined. The aim of the study was to investigate associations among circulating levels of specific POP compounds and POP-metabolites (hydroxylated PCBs [OH-PCBs] and hydroxylated PBDEs [OH-PBDEs]), steroid hormones, biological and capture variables in female polar bears. Inverse correlations were found between circulating levels of PRE and AN, and circulating levels of OH-PCBs. There were no significant relationships between the steroid concentrations and other analyzed POPs or the variables capture date and capture location (latitude and longitude), lipid content, condition and body mass. Although statistical associations do not necessarily represent direct cause-effect relationships, the present study indicate that OH-PCBs may affect the circulating levels of AN and PRE in female polar bears and that OH-PCBs thus may interfere with the steroid homeostasis. Increase in PRO and a decrease in AN concentrations suggest that the enzyme CYP17 may be a potential target for OH-PCBs. In combination with natural stressors, ongoing climate change and contaminant exposure, it is possible that OH-PCBs may disturb the reproductive potential of polar bears. Copyright © 2015 Elsevier Inc. All rights reserved.
Chinnathambi, Vijayakumar; More, Amar S; Hankins, Gary D; Yallampalli, Chandra; Sathishkumar, Kunju
2014-07-01
Pre-eclampsia is a life-threatening pregnancy disorder whose pathogenesis remains unclear. Plasma testosterone levels are elevated in pregnant women with pre-eclampsia and polycystic ovary syndrome, who often develop gestational hypertension. We tested the hypothesis that increased gestational testosterone levels induce hypertension via heightened angiotensin II signaling. Pregnant Sprague-Dawley rats were injected with vehicle or testosterone propionate from Gestational Day 15 to 19 to induce a 2-fold increase in plasma testosterone levels, similar to levels observed in clinical conditions like pre-eclampsia. A subset of rats in these two groups was given losartan, an angiotensin II type 1 receptor antagonist by gavage during the course of testosterone exposure. Blood pressure levels were assessed through a carotid arterial catheter and endothelium-independent vascular reactivity through wire myography. Angiotensin II levels in plasma and angiotensin II type 1 receptor expression in mesenteric arteries were also examined. Blood pressure levels were significantly higher on Gestational Day 20 in testosterone-treated dams than in controls. Treatment with losartan during the course of testosterone exposure significantly attenuated testosterone-induced hypertension. Plasma angiotensin II levels were not significantly different between control and testosterone-treated rats; however, elevated testosterone levels significantly increased angiotensin II type 1 receptor protein levels in the mesenteric arteries. In testosterone-treated rats, mesenteric artery contractile responses to angiotensin II were significantly greater, whereas contractile responses to K(+) depolarization and phenylephrine were unaffected. The results demonstrate that elevated testosterone during gestation induces hypertension in pregnant rats via heightened angiotensin II type 1 receptor-mediated signaling, providing a molecular mechanism linking elevated maternal testosterone levels with gestational hypertension. © 2014 by the Society for the Study of Reproduction, Inc.
Chinnathambi, Vijayakumar; More, Amar S.; Hankins, Gary D.; Yallampalli, Chandra; Sathishkumar, Kunju
2014-01-01
ABSTRACT Pre-eclampsia is a life-threatening pregnancy disorder whose pathogenesis remains unclear. Plasma testosterone levels are elevated in pregnant women with pre-eclampsia and polycystic ovary syndrome, who often develop gestational hypertension. We tested the hypothesis that increased gestational testosterone levels induce hypertension via heightened angiotensin II signaling. Pregnant Sprague-Dawley rats were injected with vehicle or testosterone propionate from Gestational Day 15 to 19 to induce a 2-fold increase in plasma testosterone levels, similar to levels observed in clinical conditions like pre-eclampsia. A subset of rats in these two groups was given losartan, an angiotensin II type 1 receptor antagonist by gavage during the course of testosterone exposure. Blood pressure levels were assessed through a carotid arterial catheter and endothelium-independent vascular reactivity through wire myography. Angiotensin II levels in plasma and angiotensin II type 1 receptor expression in mesenteric arteries were also examined. Blood pressure levels were significantly higher on Gestational Day 20 in testosterone-treated dams than in controls. Treatment with losartan during the course of testosterone exposure significantly attenuated testosterone-induced hypertension. Plasma angiotensin II levels were not significantly different between control and testosterone-treated rats; however, elevated testosterone levels significantly increased angiotensin II type 1 receptor protein levels in the mesenteric arteries. In testosterone-treated rats, mesenteric artery contractile responses to angiotensin II were significantly greater, whereas contractile responses to K+ depolarization and phenylephrine were unaffected. The results demonstrate that elevated testosterone during gestation induces hypertension in pregnant rats via heightened angiotensin II type 1 receptor-mediated signaling, providing a molecular mechanism linking elevated maternal testosterone levels with gestational hypertension. PMID:24855104
Puts, David A.; Pope, Lauramarie E.; Hill, Alexander K.; Cárdenas, Rodrigo A.; Welling, Lisa L. M.; Wheatley, John R.; Breedlove, S. Marc
2015-01-01
Across human societies and many nonhuman animals, males have greater interest in uncommitted sex (more unrestricted sociosexuality) than do females. Testosterone shows positive associations with male-typical sociosexual behavior in nonhuman animals. Yet, it remains unclear whether the human sex difference in sociosexual psychology (attitudes and desires) is mediated by testosterone, whether any relationships between testosterone and sociosexuality differ between men and women, and what the nature of these possible relationships might be. In studies to resolve these questions, we examined relationships between salivary testosterone concentrations and sociosexual psychology and behavior in men and women. We measured testosterone in all men in our sample, but only in those women taking oral contraception (OC-using women) in order to reduce the influence of ovulatory cycle variation in ovarian hormone production. We found that OC-using women did not differ from normally-ovulating women in sociosexual psychology or behavior, but that circulating testosterone mediated the sex difference in human sociosexuality and predicted sociosexual psychology in men but not OC-using women. Moreover, when sociosexual psychology was controlled, men’s sociosexual behavior (number of sexual partners) was negatively related to testosterone, suggesting that testosterone drives sociosexual psychology in men and is inhibited when those desires are fulfilled. This more complex relationship between androgen and male sexuality may reconcile some conflicting prior reports. PMID:25644313
Puts, David A; Pope, Lauramarie E; Hill, Alexander K; Cárdenas, Rodrigo A; Welling, Lisa L M; Wheatley, John R; Marc Breedlove, S
2015-04-01
Across human societies and many nonhuman animals, males have greater interest in uncommitted sex (more unrestricted sociosexuality) than do females. Testosterone shows positive associations with male-typical sociosexual behavior in nonhuman animals. Yet, it remains unclear whether the human sex difference in sociosexual psychology (attitudes and desires) is mediated by testosterone, whether any relationships between testosterone and sociosexuality differ between men and women, and what the nature of these possible relationships might be. In studies to resolve these questions, we examined relationships between salivary testosterone concentrations and sociosexual psychology and behavior in men and women. We measured testosterone in all men in our sample, but only in those women taking oral contraception (OC-using women) in order to reduce the influence of ovulatory cycle variation in ovarian hormone production. We found that OC-using women did not differ from normally-ovulating women in sociosexual psychology or behavior, but that circulating testosterone mediated the sex difference in human sociosexuality and predicted sociosexual psychology in men but not OC-using women. Moreover, when sociosexual psychology was controlled, men's sociosexual behavior (number of sexual partners) was negatively related to testosterone, suggesting that testosterone drives sociosexual psychology in men and is inhibited when those desires are fulfilled. This more complex relationship between androgens and male sexuality may reconcile some conflicting prior reports. Copyright © 2015 Elsevier Inc. All rights reserved.
Wilson, V S; LeBlanc, G A
2000-03-01
Hepatic biotransformation processes can be modulated by chemical exposure and these alterations can impact the biotransformation of endogenous substrates. Furthermore, chemically mediated alterations in the biotransformation of endogenous steroid hormones have been implicated as a mechanism by which steroid hormone homeostasis can be disrupted. The fungicide ketoconazole has been shown to lower serum testosterone levels and alter both gonadal synthesis and hepatic inactivation of testosterone. The present study examined whether the effects of ketoconazole on the hepatic biotransformation of testosterone contribute to its lowering of serum testosterone levels. Results also were used to validate further the use of the androgen-regulated hepatic testosterone 6alpha/15alpha-hydroxylase ratio as an indicator of androgen status. Male CD-1 mice were fed from 0 to 160 mg/kg ketoconazole in honey. Four h after the initial treatment, serum testosterone levels, gonadal testosterone secretion, and hepatic testosterone hydroxylase activity decreased, and the hepatic testosterone 6alpha/15alpha-hydroxylase ratio increased in a dose-dependent manner. Immunoblot analysis indicated that the transient decline in hepatic biotransformation was not due to reduced P450 protein levels. Rather, hepatic testosterone biotransformation activities were found to be differentially susceptible to direct inhibition by ketoconazole. Differential inhibition was also responsible for the increase seen in the 6alpha/15alpha-hydroxylase ratio. The changes in serum testosterone levels could be explained by decreased gonadal synthesis of testosterone and were not impacted by decreased hepatic biotransformation of testosterone. These results demonstrate that changes in the hepatic hydroxylation of testosterone by ketoconazole, and perhaps other chemicals, have little or no influence serum testosterone levels.
Yang, Eun-Jin; Wilczynski, Walter
2002-09-01
We investigated the relationship between aggressive behavior and circulating androgens in the context of agonistic social interaction and examined the effect of this interaction on the androgen-aggression relationship in response to a subsequent social challenge in male Anolis carolinensis lizards. Individuals comprising an aggressive encounter group were exposed to an aggressive conspecific male for 10 min per day during a 5-day encounter period, while controls were exposed to a neutral stimulus for the same period. On the sixth day, their responses to an intruder test were observed. At intervals, individuals were sacrificed to monitor plasma androgen levels. Structural equation modeling (SEM) was used to test three a priori interaction models of the relationship between social stimulus, aggressive behavior, and androgen. Model 1 posits that exposure to a social stimulus influences androgen and aggressive behavior independently. In Model 2, a social stimulus triggers aggressive behavior, which in turn increases circulating levels of androgen. In Model 3, exposure to a social stimulus influences circulating androgen levels, which in turn triggers aggressive behavior. During the 5 days of the encounter period, circulating testosterone (T) levels of the aggressive encounter group followed the same pattern as their aggressive behavioral responses, while the control group did not show significant changes in their aggressive behavior or T level. Our SEM results supported Model 2. A means analysis showed that during the intruder test, animals with 5 days of aggressive encounters showed more aggressive responses than did control animals, while their circulating androgen levels did not differ. This further supports Model 2, suggesting that an animal's own aggressive behavior may trigger increases in levels of plasma androgen. Copyright 2002 Elsevier Science (USA)
Cook, Michael B.; Wood, Shannon N.; Cash, Brooks D.; Young, Patrick; Acosta, Ruben D.; Falk, Roni T.; Pfeiffer, Ruth M.; Hu, Nan; Su, Hua; Wang, Lemin; Wang, Chaoyu; Gherman, Barbara; Giffen, Carol; Dykes, Cathy; Turcotte, Veronique; Caron, Patrick; Guillemette, Chantal; Dawsey, Sanford M.; Abnet, Christian C.; Hyland, Paula L.; Taylor, Philip R.
2014-01-01
Background & Aims Esophageal adenocarcinoma is believed to result from the progression of gastroesophageal reflux disease to erosive esophagitis and re-epithelialization of the esophagus with a columnar cell population termed Barrett's esophagus (BE). Men develop BE and esophageal adenocarcinoma more frequently than women, and the ratio is increasing; approximately 7 men are diagnosed with malignancy for every woman, yet little is known about the mechanisms of this difference. We assessed whether sex steroid hormones were associated with BE in a male population. Methods We analyzed data from the Barrett's Esophagus Early Detection Case Control Study, based at the Walter Reed National Military Medical Center. Blood samples were collected from 173 men with BE and 213 men without BE (controls, based on endoscopic analysis); 13 sex steroid hormones were measured by mass spectrometry and sex hormone binding globulin was measured by ELISA. We also calculated free estradiol, free testosterone and free dihydrotestosterone (DHT). We used multivariable logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for age, race, smoking status, alcohol consumption, body mass index (BMI; kg/m2), heartburn, regurgitation, and gastroesophageal symptom score (excluding heartburn and regurgitation). Results Levels of free testosterone and free DHT were positively associated with BE risk; patients in the highest quartile for these hormones were most likely to have BE (for free testosterone, OR=5.36; 95% CI, 2.21–13.03; P=0.0002 and for free DHT, OR=4.25, 95% CI, 1.87–9.66; P=.001). Level of estrone sulfate was inversely associated with BE risk (P for trend=.02). No other hormone was associated with BE risk. Relationships were not modified by age or BMI. Conclusions In an analysis of men, levels of free testosterone and free DHT were significantly associated with risk of BE. PMID:25158929
Davis, Susan R; Robinson, Penelope J; Moufarege, Alain; Bell, Robin J
2012-10-01
Sex hormone-binding globulin (SHBG) is a robust predictor of insulin resistance. Whether this is independent of circulating sex steroid levels remains uncertain. The aim of this study was to investigate the determinants of SHBG in postmenopausal women and whether the relationship between SHBG and insulin resistance is independent of oestrogen and androgen levels. A cross-sectional study of naturally and surgically menopausal women. Seven hundred and sixty three postmenopausal women not using any systemic hormone therapy, mean age 54·4 ± 5·8 years, recruited in the US, Canada, Australia, UK and Sweden between July 2004 and February 2005. Relationships between log-transformed (ln) SHBG and ln homoeostasis model assessment for insulin resistance (HOMA-IR) were explored, taking into account age, body mass index (BMI), blood pressure (BP) and circulating oestradiol, oestrone, testosterone and dihydrotestosterone. Taking into account age, race, years since menopause, menopause type, BMI, BP, prior postmenopausal hormone use and the sex steroids measured, 34·4% of the variation in SHBG could be explained by the model that included negative contributions by HOMA-IR, BMI and diastolic BP, and a positive contribution by total testosterone (P < 0·001). None of the sex steroids made independent contributions to HOMA-IR, which was best explained by the model that included BMI, SHBG, systolic BP and surgical menopause, with each variable being positively related to HOMA-IR (r(2) = 0·3152, P = 0·03). The relationship between SHBG and HOMA-IR, as an estimate of insulin resistance, is not explained by endogenous oestrogen and androgen levels and is, at least in part, independent of BMI in postmenopausal women. © 2011 Blackwell Publishing Ltd.
Zhou, Shao-Hu; Weng, Zhi-Wei; Li, Tang-Lin
2013-07-01
To investigate the effect of the method of tonifying the kidney and activating blood circulation on the testosterone secretion index (TSI) in late-onset hypogonadism (LOH) male patients with kidney deficiency and its possible mechanisms. We screened 60 LOH male patients with kidney deficiency based on the scores on Partial Androgen Deficiency in Aging Males (PADAM), the levels of serum total testosterone (TT) and luteinizing hormone (LH), and TSI (TT/LH). We randomly divided the patients into a Nan Geng Ning (NGN) group (n = 40, aged 55.02 +/- 11.37 years) and a control group (n = 20, aged 54.56 +/- 12.12 years) to be treated orally with NGN decoction and testosterone undecanoate capsules, respectively, both for 12 consecutive weeks. We obtained the scores on psychological status, physical status and sexual function and observed the changes in serum TT, LH and TSI after 4, 8 and 12 weeks of treatment. Compared with the baseline, both the NGN and control groups showed a significant reduction after 12 weeks of medication in the LH level ([5.32 +/- 2.08] vs [4.89 +/- 1.46] IU/L and [5.36 +/- 2.07] vs [4.81 +/- 1.75] IU/L, P < 0.05), psychological status score (5.2 +/- 1.3 vs 2.7 +/- 1.4 and 4.8 +/- 2.2 vs 2.9 +/- 1.2, P < 0.05), physical status score (6.9 +/- 2.5 vs 2.9 +/- 1.6 and 7.1 +/- 2.7 vs 3.1 +/- 1.5, P < 0.05) and sexual function score (10.2 +/- 3.3 vs 4.5 +/- 2.9 and 9.8 +/- 3.1 vs 4.8 +/- 3.0, P < 0.05), but a remarkable increase in the TT level ([11.13 +/- 0.69] vs [14.55 +/- 0.75] nmol/L and [10.99 +/- 0.74] vs [14.74 +/- 0.83] nmol/L, P < 0.05) and TSI ([2.14 +/- 0.65] vs [2.99 +/- 0.72] nmol/IU and ([2.05 +/- 0.73] vs [3.11 +/- 0.65] nmol/IU, P < 0.05). However, no significant differences were found between the NGN and control groups at 12 weeks in LH ([4.89 +/- 1.46] vs [4.81 +/- 1.75] IU/L, P > 0.05), TT ([14.55 +/- 0.75] vs [14.74 +/- 0.83] nmol/L, P > 0.05), TSI ([2.99 +/- 0.72] vs [3.11 +/- 0.65] nmol/IU, P > 0.05), psychological status score (2.7 +/- 1.4 vs 2.9 +/- 1.2, P > 0.05), physi- cal status score (2.9 +/- 1.6 vs 3.1 +/- 1.5, P > 0.05) and sexual function score (4.5 +/- 2.9 vs 4.8 +/- 3.0, P > 0.05). There were no adverse events in either of the two groups throughout the whole experiment. The method of tonifying the kidney and activating blood circulation could significantly improve the clinical symptoms of LOH with kidney deficiency and increase the patient's serum TT level and TSI. NGN decoction works on LOH by acting on the hypothalamic-pituitary-gonad axis.
de Ronde, Willem; Vogel, Syarda; Bui, Hong N; Heijboer, Annemieke C
2011-03-01
To investigate whether showering, to prevent the involuntary transfer of testosterone to others through skin contact, either 15 or 30 minutes after application of testosterone gel would significantly affect plasma testosterone levels. Prospective 3-way crossover trial. University hospital in the Netherlands. Ten agonadal female-to-male transsexuals who had sex-reassignment surgery at least 3 months earlier. Subjects were randomized to one of three application regimens for testosterone gel 50 mg/day, each lasting 7 days: testosterone application after showering (standard regimen), shower was taken 30 minutes after testosterone application, or shower was taken 15 minutes after testosterone application. Subjects then crossed over to each of the other two application regimens for a total of 21 days of study participation. On day 7 of each application regimen, mean plasma testosterone levels were determined before testosterone application and at 1, 4, 7, and 10 hours after application. With the standard regimen, mean plasma testosterone levels at all time points after application were in the normal range: mean ± SD average concentration 994 ± 1026 ng/dl. When a shower was taken 30 or 15 minutes after application, plasma testosterone levels at 1, 4, 7, and 10 hours were significantly lower: mean ± SD average concentration 401 ± 231 ng/dl for 30 minutes after application (p<0.01) and 320 ± 248 ng/dl for 15 minutes after application (p<0.01). Showering within 30 minutes after application of testosterone gel 50 mg/day reduces absorption of testosterone and results in unacceptably low plasma testosterone levels in most users. Therefore, this strategy cannot be recommended to prevent involuntary transfer of testosterone.
Sinha-Hikim, I; Arver, S; Beall, G; Shen, R; Guerrero, M; Sattler, F; Shikuma, C; Nelson, J C; Landgren, B M; Mazer, N A; Bhasin, S
1998-04-01
Measurements of total and free testosterone levels in women have lacked precision and accuracy because of limited assay sensitivity. The paucity of normative data on total and free testosterone levels in healthy women has confounded interpretation of androgen levels in women with human immunodeficiency virus (HIV) infection and other disease states. Therefore, the objectives of this study were to develop sensitive assays for the measurement of the low total and free testosterone levels in women to define the range for these hormones during the normal menstrual cycle and assess the total and free testosterone levels in HIV-infected women. By using a larger volume of serum, increasing the incubation time, and reducing the antibody concentration, the sensitivity of the total testosterone assay was increased to 0.008 nmol/L, and that of the free testosterone assay was increased to 2 pmol/L. The mean percent free testosterone was 1.0 +/- 0.1% of the total testosterone. Serum total and free testosterone levels in the follicular and luteal phases were not significantly different, but both demonstrated a modest preovulatory increase, 3 days before the LH peak. Serum total [0.50 +/- 0.32 (14.60 +/- 9.22) vs. 1.2 +/- 0.7 nmol/L (34.3 +/- 21.0 ng/dL); P < 0.0001] and free testosterone levels (5.56 +/- 2.70 (1.58 +/- 0.80) vs. 12.8 +/- 5.5 pmol/L (3.4 +/- 1.7 pg/mL); P < 0.0001) were significantly lower in HIV-infected women (n = 37) than in healthy women (n = 34). Serum total and free testosterone levels were also significantly lower in HIV-infected women who were menstruating normally. There were no significant differences in serum total and free testosterone levels between those who had lost weight and those who had not. Testosterone levels correlated inversely with plasma HIV ribonucleic acid copy number. Serum FSH, but not LH, levels were significantly higher in HIV-infected women than in controls. Using assays with sufficient sensitivity, we defined the range for total and free testosterone levels during the normal menstrual cycle. Serum total and free testosterone levels are lower in HIV-infected women and correlate inversely with plasma HIV ribonucleic acid levels. The hypothesis that androgen deficiency contributes to wasting in HIV-infected women remains to be tested.
"Low Testosterone Levels in Body Fluids Are Associated With Chronic Periodontitis".
Kellesarian, Sergio Varela; Malmstrom, Hans; Abduljabbar, Tariq; Vohra, Fahim; Kellesarian, Tammy Varela; Javed, Fawad; Romanos, Georgios E
2017-03-01
There is a debate over the association between low testosterone levels in body fluids and the occurrence of chronic periodontitis (CP). The aim of the present systematic review was to assess whether low testosterone levels in body fluids reflect CP. In order to identify studies relevant to the focus question: "Is there a relationship between low testosterone levels in body fluids and CP?" an electronic search without time or language restrictions was conducted up to June 2016 in indexed databases using different keywords: periodontitis, chronic periodontitis, periodontal diseases, testosterone, and gonadal steroid hormones. A total of eight studies were included in the present systematic review. The number of study participants ranged from 24 to 1,838 male individuals with ages ranging from 15 to 95 years. Seven studies measured testosterone levels in serum, two studies in saliva, and one study in gingiva. Four studies reported a negative association between serum testosterone levels and CP. Two studies reported a positive association between decreased testosterone levels in serum and CP. Increased levels of salivary testosterone among patients with CP were reported in one study; whereas one study reported no significant difference in the concentration of salivary testosterone between patients with and without CP. One study identified significant increase in the metabolism of testosterone in the gingiva of patients with CP. Within the limits of the evidence available, the relationship between low testosterone levels and CP remains debatable and further longitudinal studies and control trials are needed.
“Low Testosterone Levels in Body Fluids Are Associated With Chronic Periodontitis”
Kellesarian, Sergio Varela; Malmstrom, Hans; Abduljabbar, Tariq; Vohra, Fahim; Kellesarian, Tammy Varela; Javed, Fawad; Romanos, Georgios E.
2016-01-01
There is a debate over the association between low testosterone levels in body fluids and the occurrence of chronic periodontitis (CP). The aim of the present systematic review was to assess whether low testosterone levels in body fluids reflect CP. In order to identify studies relevant to the focus question: “Is there a relationship between low testosterone levels in body fluids and CP?” an electronic search without time or language restrictions was conducted up to June 2016 in indexed databases using different keywords: periodontitis, chronic periodontitis, periodontal diseases, testosterone, and gonadal steroid hormones. A total of eight studies were included in the present systematic review. The number of study participants ranged from 24 to 1,838 male individuals with ages ranging from 15 to 95 years. Seven studies measured testosterone levels in serum, two studies in saliva, and one study in gingiva. Four studies reported a negative association between serum testosterone levels and CP. Two studies reported a positive association between decreased testosterone levels in serum and CP. Increased levels of salivary testosterone among patients with CP were reported in one study; whereas one study reported no significant difference in the concentration of salivary testosterone between patients with and without CP. One study identified significant increase in the metabolism of testosterone in the gingiva of patients with CP. Within the limits of the evidence available, the relationship between low testosterone levels and CP remains debatable and further longitudinal studies and control trials are needed. PMID:27645514
Rittmaster, R S; Thompson, D L
1990-04-01
Ten hirsute women with polycystic ovarian syndrome (PCO) and nine with idiopathic hirsutism (IH) underwent selective ovarian suppression with leuprolide for 5-6 months and then were randomized to receive, in addition, dexamethasone or placebo for 4 more months. Serum hormone levels and hair growth rates were determined before and after each treatment period. During the initial treatment period with leuprolide alone, testosterone decreased by 54 +/- 6% (mean +/- SEM) in PCO and by 36 +/- 3% in IH (P = 0.02). Androstenedione decreased by 53 +/- 6% in PCO and by 31 +/- 7% in IH (P = 0.02). Androstanediol glucuronide (Adiol-G) decreased by 14 +/- 6% in PCO and by 7 +/- 3% in IH. There was no change in dehydroepiandrosterone sulfate (DHEAS). While initial serum androgen levels were higher in PCO than in IH, they were similar after ovarian suppression in the two groups. After ovarian suppression, Adiol-G was more consistently correlated with testosterone and androstenedione than was DHEAS, suggesting that Adiol-G may be a better marker than DHEAS of adrenal androgen secretion. Hair growth rates decreased by 37 +/- 6% in PCO and by 14 +/- 10% in IH (P = 0.07). The change in hair growth correlated with the change in androstenedione (r = 0.66; P = 0.002), but not significantly with the change in testosterone (r = 0.29; P = 0.2). After the addition of dexamethasone therapy (0.5 mg daily), testosterone, androstenedione, and DHEAS levels fell to near or below assay detection limits, while Adiol-G decreased by 80 +/- 3%. Hair growth rates decreased slightly more in women during dexamethasone (46 +/- 6%) than during placebo (26 +/- 9%; P = 0.18). In summary, the ovary was the major source of circulating testosterone and androstenedione in PCO. The adrenal contributed a substantial minority of these hormones in PCO and was the major source of androgen secretion in IH. Adrenal hyperandrogenism was common in both IH and PCO. Hair growth rates correlated best with changes in serum androstenedione levels. Adiol-G, which was derived primarily from adrenal precursors, was a better marker of adrenal androgen secretion than was DHEAS in these subjects.
Longitudinal development of hormone levels and grey matter density in 9 and 12-year-old twins.
Brouwer, Rachel M; Koenis, M M G; Schnack, Hugo G; van Baal, G Caroline; van Soelen, Inge L C; Boomsma, Dorret I; Hulshoff Pol, Hilleke E
2015-05-01
Puberty is characterized by major changes in hormone levels and structural changes in the brain. To what extent these changes are associated and to what extent genes or environmental influences drive such an association is not clear. We acquired circulating levels of luteinizing hormone, follicle stimulating hormone (FSH), estradiol and testosterone and magnetic resonance images of the brain from 190 twins at age 9 [9.2 (0.11) years; 99 females/91 males]. This protocol was repeated at age 12 [12.1 (0.26) years] in 125 of these children (59 females/66 males). Using voxel-based morphometry, we tested whether circulating hormone levels are associated with grey matter density in boys and girls in a longitudinal, genetically informative design. In girls, changes in FSH level between the age of 9 and 12 positively associated with changes in grey matter density in areas covering the left hippocampus, left (pre)frontal areas, right cerebellum, and left anterior cingulate and precuneus. This association was mainly driven by environmental factors unique to the individual (i.e. the non-shared environment). In 12-year-old girls, a higher level of circulating estradiol levels was associated with lower grey matter density in frontal and parietal areas. This association was driven by environmental factors shared among the members of a twin pair. These findings show a pattern of physical and brain development going hand in hand.
Remy, J J; Couture, L; Rabesona, H; Haertle, T; Salesse, R
1996-11-01
Pituitary gonadotropin hormones lutropin (LH) and follitropin (FSH) control steroidogenesis and gametogenesis in male and female gonads through interaction with G protein-coupled receptors, LHR and FSHR. In the male, LH acts on leydig cells and is mostly responsible for the acquisition of puberty and the production of androgens while FSH, together with androgens, regulates spermatogenesis within Sertoli cells. We have engineered filamentous phages displaying mouse LHR and human FSHR decapeptides chosen in hormone binding regions. Peptides from both receptors displayed on phages belong either to the receptor specific exon 1 (amino acids 18-27) or to the homologous exon 4 (amino acids 98-107). Vaccination of prepubertal BALB/c male mice with hybrid phages using sub-cutaneous or intraperitoneal injections induced immunity against receptors. Anti-receptor immunization produced agonist or antagonist effects depending only on the circulating levels of the antibodies. Both anti-LHR and anti-FSHR vaccines induced efficient as well as reversible male contraception, through different mechanisms: targeting LH receptors inhibited or hyperstimulated Leydig cell testosterone production while targeting FSH receptors did not affect testosterone levels.
Eikenaar, Cas; Husak, Jerry; Escallón, Camilo; Moore, Ignacio T
2012-11-01
Latitudinal variation in life-history traits has been the focus of numerous investigations, but underlying hormonal mechanisms have received much less attention. Steroid hormones play a central role in vertebrate reproduction and may be associated with life-history trade-offs. Consequently, circulating concentrations of these hormones vary tremendously across vertebrates, yet interspecific geographic variation in male hormone concentrations has been studied in detail only in birds. We here report on such variation in amphibians and reptiles, confirming patterns observed in birds. Using phylogenetic comparative analyses, we found that in amphibians, but not in reptiles, testosterone and baseline corticosterone were positively related to latitude. Baseline corticosterone was negatively related to elevation in amphibians but not in reptiles. For both groups, testosterone concentrations were negatively related to breeding-season length. In addition, testosterone concentrations were positively correlated with baseline corticosterone in both groups. Our findings may best be explained by the hypothesis that shorter breeding seasons increase male-male competition, which may favor increased testosterone concentrations that modulate secondary sexual traits. Elevated energetic demands resulting from greater reproductive intensity may require higher baseline corticosterone. Thus, the positive relationship between testosterone and corticosterone in both groups suggests an energetic demand for testosterone-regulated behavior that is met with increased baseline glucocorticoid concentrations.
Experimental evidence that corticosterone affects offspring sex ratios in quail
Pike, Thomas W; Petrie, Marion
2006-01-01
Recent studies have shown that some species of birds have a remarkable degree of control over the sex ratio of offspring they produce. However, the mechanism by which they achieve this feat is unknown. Hormones circulating in the breeding female are particularly sensitive to environmental perturbations, and so could provide a mechanism for her to bias the sex ratio of her offspring in favour of the sex that would derive greatest benefit from the prevailing environmental conditions. Here, we present details of an experiment in which we manipulated levels of testosterone, 17β-oestradiol and corticosterone in breeding female Japanese quail (Coturnix coturnix japonica) using Silastic implants and looked for effects on the sex ratio of offspring produced. Offspring sex ratio in this species was significantly correlated with faecal concentrations of the principal avian stress hormone, corticosterone, and artificially elevated levels of corticosterone resulted in significantly female-biased sex ratios at laying. Varying testosterone and 17β-oestradiol had no effect on sex ratio alone, and faecal levels of these hormones did not vary in response to corticosterone. Our results suggest that corticosterone may be part of the sex-biasing process in birds. PMID:16600886
Association of testosterone levels and heroin usage characteristics in male heroin users.
Wang, Zhuo; Zhou, Xiao-Bo; Yang, Xiao-Rong; Song, Hui; Cao, Bing-Rong; Yin, Fei; Kang, Lin; An, Zhen-Mei; Li, Jing
2017-05-01
Previous studies have shown that heroin abuse can alter the gonadal functions. Few studies examined the association between testosterone levels and heroin use in the existing literature. We aimed to determine the association between gonadal hormones and heroin usage characteristics over 12 weeks of abstinence in heroin users. We collected data on patient demographics and heroin use patterns for 65 men aged 18 to 45 and for 29 age-matched healthy controls. Serum levels of total testosterone, estradiol, and prolactin were assessed at 5 time points. Testosterone levels gradually increased and prolactin levels decreased in heroin users in this study. In heroin users, a significant positive correlation was observed between the way of using drug and the testosterone levels, the way of using drug and the estradiol levels, between the duration of heroin dependence and the testosterone levels, between the duration of heroin dependence and the estradiol levels on D0, and between relapse time and testosterone levels on D84. Our data reveal testosterone might promote injection drug use and repeated relapse in male heroin users.
More, Amar S; Mishra, Jay S; Hankins, Gary D; Kumar, Sathish
2016-08-01
Plasma testosterone levels are elevated in pregnant women with preeclampsia and polycystic ovaries; their offspring are at increased risk for hypertension during adult life. We tested the hypothesis that prenatal testosterone exposure induces dysregulation of the renin-angiotensin-aldosterone system, which is known to play an important role in water and electrolyte balance and blood pressure regulation. Female rats (6 mo old) prenatally exposed to testosterone were examined for adrenal expression of steroidogenic genes, telemetric blood pressure, blood volume and Na(+) and K(+) levels, plasma aldosterone, angiotensin II and vasopressin levels, and vascular responses to angiotensin II and arg(8)-vasopressin. The levels of Cyp11b2 (aldosterone synthase), but not the other adrenal steroidogenic genes, were decreased in testosterone females. Accordingly, plasma aldosterone levels were lower in testosterone females. Plasma volume and serum and urine Na(+) and K(+) levels were not significantly different between control and testosterone females; however, prenatal testosterone exposure significantly increased plasma vasopressin and angiotensin II levels and arterial pressure in adult females. In testosterone females, mesenteric artery contractile responses to angiotensin II were significantly greater, while contractile responses to vasopressin were unaffected. Angiotensin II type-1 receptor expression was increased, while angiotensin II type-2 receptor was decreased in testosterone arteries. These results suggest that prenatal testosterone exposure downregulates adrenal Cyp11b2 expression, leading to decreased plasma aldosterone levels. Elevated angiotensin II and vasopressin levels along with enhanced vascular responsiveness to angiotensin II may serve as an underlying mechanism to maintain plasma volume and Na(+) and K(+) levels and mediate hypertension in adult testosterone females. © 2016 by the Society for the Study of Reproduction, Inc.
Conversion of blood androgens to estrogens in normal adult men and women
Longcope, Christopher; Kato, Tatsuo; Horton, Richard
1969-01-01
Continuous infusions of Δ4-androstenedione-7-3H and testosterone-7-3H have been used to demonstrate that these androgens are converted to estrone and 17β-estradiol, and contribute to the circulating blood levels of these estrogens in normal males and females. The conversion ratio (ratio of concentrations of radioactivity of free product steroid [χ-PRO] and free precursor steroid [χ-PRE], both corrected for recoveries, after an infusion of radioactive precursor steroid) for androstenedione (precursor) to estrone (product) is 0.013 in males and 0.007 in females, and the conversion ratio for testosterone (precursor) to estradiol (product) is 0.0018 in males and 0.005 in females. The transfer constant, [ρ]BBAE1, for androstenedione conversion to estrone ([ρ]BBAE1 = per cent of infused androstenedione, precursor, converted to estrone, product, when infusion and measurement are both in blood) is 1.35% in males and 0.74% in females, and the transfer constant, [ρ]BBTE2, for testosterone conversion to estradiol is 0.39% in males and 0.15% in females. Whether measured as conversion ratio or transfer constant, the peripheral aromatization of androstenedione takes place to a greater degree than that of testosterone, and, for the respective androgens, both the conversion ratio and [ρ]BB value are greater in males than females. For the androgen interconversions, [ρ]BBAT is 4.5% in males and 2.2% in females; [ρ]BBTA is 8.2% in males and 12.0% in females. Studies on the distribution coefficients (effective concentration in red cells/plasma) for precursor radioactivity were also made. In both males and females the distribution coefficient for androstenedione is 0.16-0.17 while that of testosterone is 0.01-0.03. PMID:5355335
Elzanaty, Saad; Rezanezhad, Babak; Dohle, Gert
2017-04-01
The aim of the present study was to evaluate the association between serum testosterone and PSA levels in middle-aged healthy men from the general population. Based on 119 healthy men from the general population, total testosterone and PSA levels were measured. Demographic data regarding BMI, waist-to-hip ratio, smoking, and alcohol consumption were also collected. Men were classified into two groups according to testosterone levels; hypogonadal (testosterone ≤ 12 nmol/l), and eugonadal (testosterone > 12 nmol/l). The mean age of the subjects was 55 years (range 46-60 years). No significant correlation between serum testosterone and PSA levels was found (p = 0.60). PSA levels were similar when compared between hypogonadal and eugonadal men (1.4 µg/l vs. 1.4 µg/l, p = 0.90). When using a multivariate analysis model adjusted for the age of the subjects, BMI, waist-to-hip ratio, smoking, and alcohol consumption, a positive significant association between testosterone and PSA levels was found (β = 0.03, 95 % CI = 0.003-0.062, p = 0.03). Only after adjusted multivariate analysis, our results indicated that testosterone was associated with PSA levels in middle-aged healthy men.
CSF and plasma testosterone in attempted suicide.
Stefansson, Jon; Chatzittofis, Andreas; Nordström, Peter; Arver, Stefan; Åsberg, Marie; Jokinen, Jussi
2016-12-01
Very few studies have assessed testosterone levels in the cerebrospinal fluid in suicide attempters. Aggressiveness and impulsivity are common behavioural traits in suicide attempters. Dual-hormone serotonergic theory on human impulsive aggression implies high testosterone/cortisol ratio acting on the amygdala and low serotonin in the prefrontal cortex. Our aim was to examine the CSF and plasma testosterone levels in suicide attempters and in healthy volunteers. We also assessed the relationship between the testosterone/cortisol ratio, aggressiveness and impulsivity in suicide attempters. 28 medication-free suicide attempters and 19 healthy volunteers participated in the study. CSF and plasma testosterone sulfate and cortisol levels were assessed with specific radio-immunoassays. The Karolinska Scales of Personality was used to assess impulsivity and aggressiveness. All patients were followed up for cause of death. The mean follow-up period was 21 years. Male suicide attempters had higher CSF and plasma testosterone levels than age- matched male healthy volunteers. There were no significant differences in CSF testosterone levels in female suicide attempters and healthy female volunteers. Testosterone levels did not differ significantly in suicide victims compared to survivors. In male suicide attempters, the CSF testosterone/cortisol ratio showed a significant positive correlation with both impulsivity and aggressiveness. Higher CSF testosterone levels may be associated with attempted suicide in young men through association with both aggressiveness and impulsivity, a key endophenotype in young male suicide attempters. Copyright © 2016 Elsevier Ltd. All rights reserved.
Low- and high-testosterone individuals exhibit decreased aversion to economic risk.
Stanton, Steven J; Mullette-Gillman, O'Dhaniel A; McLaurin, R Edward; Kuhn, Cynthia M; LaBar, Kevin S; Platt, Michael L; Huettel, Scott A
2011-04-01
Testosterone is positively associated with risk-taking behavior in social domains (e.g., crime, physical aggression). However, the scant research linking testosterone to economic risk preferences presents inconsistent findings. We examined the relationship between endogenous testosterone and individuals' economic preferences (i.e., risk preference, ambiguity preference, and loss aversion) in a large sample (N = 298) of men and women. We found that endogenous testosterone levels have a significant U-shaped association with individuals' risk and ambiguity preferences, but not loss aversion. Specifically, individuals with low or high levels of testosterone (more than 1.5 SD from the mean for their gender) were risk and ambiguity neutral, whereas individuals with intermediate levels of testosterone were risk and ambiguity averse. This relationship was highly similar in men and women. In contrast to received wisdom regarding testosterone and risk, the present data provide the first robust evidence for a nonlinear association between economic preferences and levels of endogenous testosterone.
Association of testosterone and BDNF serum levels with craving during alcohol withdrawal.
Heberlein, Annemarie; Lenz, Bernd; Opfermann, Birgitt; Gröschl, Michael; Janke, Eva; Stange, Katrin; Groh, Adrian; Kornhuber, Johannes; Frieling, Helge; Bleich, Stefan; Hillemacher, Thomas
2016-08-01
Preclinical and clinical studies show associations between testosterone and brain-derived neurotrophic growth factor (BDNF) serum levels. BDNF and testosterone have been independently reported to influence alcohol consumption. Therefore, we aimed to investigate a possible interplay of testosterone and BDNF contributing to alcohol dependence. Regarding possible interplay of testosterone and BDNF and the activity of the hypothalamic pituitary axis (HPA), we included cortisol serum levels in our research. We investigated testosterone and BDNF serum levels in a sample of 99 male alcohol-dependent patients during alcohol withdrawal (day 1, 7, and 14) and compared them to a healthy male control group (n = 17). The testosterone serum levels were significantly (p < 0.001) higher in the patients' group than in the control group and decreased significantly during alcohol withdrawal (p < 0.001). The decrease of testosterone serum levels during alcohol withdrawal (days 1-7) was significantly associated with the BDNF serum levels (day 1: p = 0.008). In a subgroup of patients showing high cortisol serum levels (putatively mirroring high HPA activity), we found a significant association of BDNF and testosterone as well as with alcohol craving measured by the Obsessive and Compulsive Drinking Scale (OCDS). Our data suggest a possible association of BDNF and testosterone serum levels, which may be relevant for the symptomatology of alcohol dependence. Further studies are needed to clarify our results. Copyright © 2016 Elsevier Inc. All rights reserved.
Wei, Yuan; Zhou, Xin; Fang, Cheng; Li, Lei; Kluetzman, Kerri; Yang, Weizhu; Zhang, Qing-Yu; Ding, Xinxin
2010-07-01
A mouse model termed Cpr-low (CL) was recently generated, in which the expression of the cytochrome P450 reductase (Cpr) gene was globally down-regulated. The decreased CPR expression was accompanied by phenotypical changes, including reduced embryonic survival, decreases in circulating cholesterol, increases in hepatic P450 expression, and female infertility (accompanied by elevated serum testosterone and progesterone levels). In the present study, a complementary mouse model [named reversible-CL (r-CL)] was generated, in which the reduced CPR expression can be reversed in an organ-specific fashion. The neo cassette, which was inserted into the last Cpr intron in r-CL mice, can be deleted by Cre recombinase, thus returning the structure of the Cpr gene (and hence CPR expression) to normal in Cre-expressing cells. All previously identified phenotypes of the CL mice were preserved in the r-CL mice. As a first application of the r-CL model, we have generated an extrahepatic-CL (xh-CL) mouse for testing of the functions of CPR-dependent enzymes in all extrahepatic tissues. The xh-CL mice, generated by mating of r-CL mice with albumin-Cre mice, had normal CPR expression in hepatocytes but down-regulated CPR expression elsewhere. They were indistinguishable from wild-type mice in body and liver weights, circulating cholesterol levels, and hepatic microsomal P450 expression and activities; however, they still showed elevated serum testosterone and progesterone levels and sterility in females. Embryonic lethality was prevented in males, but apparently not in females, indicating a critical role for fetal hepatic CPR-dependent enzymes in embryonic development, at least in males.
Sato, K; Samocha-Bonet, D; Handelsman, D J; Fujita, S; Wittert, G A; Heilbronn, L K
2014-12-01
Low-circulating testosterone is associated with development of type 2 diabetes in obese men. In this study, we examined the effects of experimental overfeeding and weight gain on serum levels of sex hormones and skeletal muscle expression of steroidogenic enzymes in healthy men with (FH+) and without (FH-) a family history of type 2 diabetes. Following a 3-day lead in energy balanced diet, FH+ (n = 9) and FH- men (n = 11) were overfed by 5200 kJ/day (45% fat) for 28 days. Body weight, fasting glucose, insulin, sex steroid, sex hormone binding globulin (SHBG) levels, insulin sensitivity (hyperinsulinaemic-euglycaemic clamp) and body fat (DXA) were assessed in all individuals at baseline and day 28, and sex steroidogenesis-related enzyme expression in vastus lateralis biopsies was examined in a subset (n = 11). Body weight, fat mass and fasting insulin levels were increased by overfeeding (P < 0.01) and insulin was increased significantly more in FH+ men (P<0.01). Serum sex hormone binding globulin (SHBG) and 5α-dihydrotestosterone (DHT) were reduced with overfeeding (P < 0.05), and serum testosterone and DHT were reduced to a greater extent in FH+ men (P < 0.05). Overfeeding reduced mRNA expression of 3β-hydroxysteroid dehydrogenase (HSD) and 17βHSD (P ≤ 0.007), independently of group. 5α-Reductase (SRD5A1) mRNA expression was not changed overall, but a time by group interaction was observed (P = 0.04). Overfeeding reduced SHBG and muscle expression of enzymes involved in the formation of testosterone in skeletal muscle. Men with a family history of T2DM were more susceptible to deleterious outcomes of overfeeding with greater reductions in serum testosterone and DHT and greater increases in markers of insulin resistance, which may contribute to increased risk of developing type 2 diabetes. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Age-related testosterone decline in a Brazilian cohort of healthy military men.
Nardozza Júnior, Archimedes; Szelbracikowski, Sergio dos Santos; Nardi, Aguinaldo Cesar; Almeida, Jose Carlos de
2011-01-01
Androgen decline in the aging man has become a topic of increasing clinical relevance worldwide, as the reduction in testosterone levels has been reported to be accompanied by loss of muscle mass, accumulation of central adiposity, impaired mobility and increase risk of bone fractures. Although well-established in studies conducted in developed countries, progressive decline in serum testosterone levels with age has been poorly investigated in Brazil. To determine the pattern of blood testosterone concentrations decline with age in a cohort of Brazilian healthy military men. We retrospectively reviewed data on serum testosterone measurements of healthy individuals that had undergone a routine check-up at the Military Biology Institute. Blood samples were obtained early in the morning, and total testosterone concentration was determined using a commercial chemoluminescent immunoassay. Mean values were analyzed in five age groups: ≤ 40, 41 to 50, 51 to 60, 61 to 70, and > 70 years. Mean total testosterone levels. 1,623 subjects were included in the analysis; mean age was 57 years (24 to 87), and mean testosterone level was 575.5 ng/dL (25.0 to 1308.0 ng/dL). The evaluation of age-related changes in total testosterone levels revealed a progressive reduction in serum levels of this hormone with increasing age. Testosterone levels below 300 ng/dL were reported in 321 participants, a prevalence of nearly 20% in the study population. In agreement with other findings, a reduction of total testosterone levels with age was reported for healthy Brazilian men.
Lévesque, Éric; Laverdière, Isabelle; Lacombe, Louis; Caron, Patrick; Rouleau, Mélanie; Turcotte, Véronique; Têtu, Bernard; Fradet, Yves; Guillemette, Chantal
2014-02-01
Polymorphisms in the genes SRD5A1 and SRD5A2 encoding androgen biosynthetic 5α-reductase enzymes have been associated with an altered risk of biochemical recurrence after radical prostatectomy in localized prostate cancer. To gain potential insights into SRD5A biologic effects, we examined the relationship between SRD5A prognostic markers and endogenous sex-steroid levels measured by mass spectrometry in plasma samples and corresponding prostatic tissues of patients with prostate cancer. We report that five of the seven SRD5A markers differentially affect sex-steroid profiles of dihydrotestosterone and its metabolites in both the circulation and prostatic tissues of patients with prostate cancer. Remarkably, a 32% increase in intraprostatic testosterone levels was observed in the presence of the high-risk SRD5A rs2208532 polymorphism. Moreover, SRD5A2 markers were associated predominantly with circulating levels of inactive glucuronides. Indeed, the rs12470143 SRD5A2 protective allele was associated with high circulating androstane-3α, 17β-diol-17-glucuronide (3α-diol-17G) levels as opposed to lower levels of both 3α-diol-17G and androsterone-glucuronide observed with the rs2208532 SRD5A2 risk allele. Moreover, SRD5A2 rs676033 and rs523349 (V89L) risk variants, in strong linkage disequilibrium, were associated with higher circulating levels of 3α-diol-3G. The SRD5A2 rs676033 variant further correlated with enhanced intraprostatic exposure to 5α-reduced steroids (dihydrotestosterone and its metabolite 3β-diol). Similarly, the SRD5A1 rs166050C risk variant was associated with greater prostatic exposure to androsterone, whereas no association was noted with circulating steroids. Our data support the association of 5α-reductase germline polymorphisms with the hormonal milieu in patients with prostate cancer. Further studies are needed to evaluate if these variants influence 5α-reductase inhibitor efficacy. ©2013 AACR.
HIROKAWA, Kumi; MIWA, Machiko; TANIGUCHI, Toshiyo; TSUCHIYA, Masao; KAWAKAMI, Norito
2015-01-01
Levels of job stress have been shown to be inversely associated with testosterone levels, but some inconsistent results have been documented. We investigated the moderating effects of testosterone levels on associations between job stress-factors and psychological stress responses in Japanese medical workers. The participants were 63 medical staff (20 males and 43 women; mean age: 30.6 years; SD=7.3) in Okayama, Japan. Their job-stress levels and psychological stress responses were evaluated using self-administered questionnaires, and their salivary testosterone collected. Multiple regression analyses showed that job demand was positively associated with stress responses in men and women. An interaction between testosterone and support from colleagues had a significant effect on depression and anxiety for women. In women with lower testosterone levels, a reducing effect of support from colleagues on depression and anxiety was intensified. In women with higher testosterone levels, depression and anxiety levels were identical regardless of support from colleagues. Testosterone may function as a moderator between perceived work environment and psychological stress responses for female medical workers. PMID:26632120
Heany, Sarah J; van Honk, Jack; Stein, Dan J; Brooks, Samantha J
2016-02-01
Social and affective research in humans is increasingly using functional and structural neuroimaging techniques to aid the understanding of how hormones, such as testosterone, modulate a wide range of psychological processes. We conducted a meta-analysis of functional magnetic resonance imaging (fMRI) studies of testosterone administration, and of fMRI studies that measured endogenous levels of the hormone, in relation to social and affective stimuli. Furthermore, we conducted a review of structural MRI i.e. voxel based morphometry (VBM) studies which considered brain volume in relation to testosterone levels in adults and in children. In the included testosterone administration fMRI studies, which consisted of female samples only, bilateral amygdala/parahippocampal regions as well as the right caudate were significantly activated by social-affective stimuli in the testosterone condition. In the studies considering endogenous levels of testosterone, stimuli-invoked activations relating to testosterone levels were noted in the bilateral amygdala/parahippocampal regions and the brainstem. When the endogenous testosterone studies were split by sex, the significant activation of the brain stem was seen in the female samples only. Significant stimuli-invoked deactivations relating to endogenous testosterone levels were also seen in the right and left amygdala/parahippocampal regions studies. The findings of the VBM studies were less consistent. In adults larger volumes in the limbic and temporal regions were associated with higher endogenous testosterone. In children, boys showed a positive correlation between testosterone and brain volume in many regions, including the amygdala, as well as global grey matter volume, while girls showed a neutral or negative association between testosterone levels and many brain volumes. In conclusion, amygdalar and parahippocampal regions appear to be key target regions for the acute actions of testosterone in response to social and affective stimuli, while neurodevelopmentally the volumes of a broader network of brain structures are associated with testosterone levels in a sexually dimorphic manner.
Sex-specific impact of prenatal stress on growth and reproductive parameters of guinea pigs.
Schöpper, Hanna; Klaus, Teresa; Palme, Rupert; Ruf, Thomas; Huber, Susanne
2012-12-01
Body condition and reproductive maturation are parameters of reproductive success that are influenced by sexual hormones rising in the circulation during the time of puberty. Various endocrine systems can be programmed by conditions experienced during early life. Stress for instance is supposed to be capable of influencing fetal development, leading to adjustments of offspring's later physiology. We examined whether prenatal stress (induced by exposure to strobe light) during early- to mid-gestation was capable of affecting later reproductive parameters in guinea pigs (Cavia aperea f. porcellus). Therefore, we measured the levels of testosterone and progesterone from the age of day 12-124 in prenatally stressed (PS, n = 20) and unaffected control animals (n = 24). Furthermore, we determined the timing of puberty and growth. Body weight development revealed significantly faster growth in PS females compared to control animals. The onset of first estrus was slightly earlier in PS females, however not significantly so. Cycle lengths and levels of progesterone differed between groups over the course of time with higher progesterone levels and more constant cycles among PS females compared to control females who displayed marked differences between first and subsequent cycles. Levels of testosterone did not differ between groups. We conclude that prenatal stress accelerates growth and maturity in females, but not in males.
Chen, Zhuo; Tao, Sha; Gao, Yong; Zhang, Ju; Hu, Yanling; Mo, Linjian; Kim, Seong-Tae; Yang, Xiaobo; Tan, Aihua; Zhang, Haiying; Qin, Xue; Li, Li; Wu, Yongming; Zhang, Shijun; Zheng, S Lilly; Xu, Jianfeng; Mo, Zengnan; Sun, Jielin
2013-12-01
Sex hormones and gonadotropins exert a wide variety of effects in physiological and pathological processes. Accumulated evidence shows a strong heritable component of circulating concentrations of these hormones. Recently, several genome-wide association studies (GWASs) conducted in Caucasians have identified multiple loci that influence serum levels of sex hormones. However, the genetic determinants remain unknown in Chinese populations. In this study, we aimed to identify genetic variants associated with major sex hormones, gonadotropins, including testosterone, oestradiol, follicle-stimulating hormone (FSH), luteinising hormone (LH) and sex hormone binding globulin (SHBG) in a Chinese population. A two-stage GWAS was conducted in a total of 3495 healthy Chinese men (1999 subjects in the GWAS discovery stage and 1496 in the confirmation stage). We identified a novel genetic region at 15q21.2 (rs2414095 in CYP19A1), which was significantly associated with oestradiol and FSH in the Chinese population at a genome-wide significant level (p=6.54×10(-31) and 1.59×10(-16), respectively). Another single nucleotide polymorphism in CYP19A1 gene was significantly associated with oestradiol level (rs2445762, p=7.75×10(-28)). In addition, we confirmed the previous GWAS-identified locus at 17p13.1 for testosterone (rs2075230, p=1.13×10(-8)) and SHBG level (rs2075230, p=4.75×10(-19)) in the Chinese population. This study is the first GWAS investigation of genetic determinants of FSH and LH. The identification of novel susceptibility loci may provide more biological implications for the synthesis and metabolism of these hormones. More importantly, the confirmation of the genetic loci for testosterone and SHBG suggests common genetic components shared among different ethnicities.
Jasuja, Guneet Kaur; Travison, Thomas G; Murabito, Joanne M; Davda, Maithili N; Rose, Adam J; Basaria, Shehzad; Coviello, Andrea; Vasan, Ramachandran S; D'Agostino, Ralph; Bhasin, Shalender
2017-08-01
Self-rated health is a commonly used global indicator of health status. Few studies have examined the association of self-rated health and mobility with estrone and estradiol in men. Accordingly, we determined the cross-sectional, incident, and mediating relations between circulating estrone and estradiol levels with self-rated health, mobility limitation, and physical performance in community-dwelling men. The cross-sectional sample included 1,148 men, who attended Framingham Offspring Study Examinations 7 and 8. Estrone and estradiol levels were measured using liquid chromatography tandem mass spectrometry at Examination 7. Self-reported mobility limitation and self-rated health were assessed at Examinations 7 and 8. Additionally, short physical performance battery, usual walking speed, and grip strength were assessed at Examination 7. In incident analysis, estradiol levels at Examination 7 were associated with increased odds of fair or poor self-rated health at Examination 8, after adjusting for age, body mass index, comorbidities, and testosterone levels; in an individual with 50% greater estradiol than other, the odds of reporting "fair or poor" self-rated health increased by 1.78 (95% confidence interval: 1.25-2.55; p = .001). Neither estrone nor estradiol levels were associated with any physical performance measure at baseline. Higher circulating levels of estradiol are associated with increased risk of incident fair/poor self-rated health in community-dwelling men. The mechanisms by which circulating levels of estradiol are related to self-rated health in men need further investigation. Published by Oxford University Press on behalf of The Gerontological Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Lund, T D; Rhees, R W; Setchell, K D; Lephart, E D
2001-09-28
Naturally occurring estrogen-like molecules in plants (phytoestrogens), present via soy, in animal diets can alter morphology and physiology in rodents. Phytoestrogens have the ability to bind estrogen receptors and exert many of the biological responses evoked by physiological estrogens. This study characterized the effects of dietary phytoestrogens on the expression of body and prostate weight, circulating testosterone and estradiol levels, puberty onset, vaginal cyclicity, and volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) in Long-Evans rats. Using different experimental protocols, animals were fed either a phytoestrogen-rich (Phyto-600) or a phytoestrogen-free (Phyto-free) diet. Animals fed the Phyto-600 diet displayed significantly decreased body weights (in males and females), prostate weights and delayed puberty in females compared to that of animals fed the Phyto-free diet. Circulating testosterone or estradiol levels in males or estrous cyclicity were not altered by the diets. The volume of the SDN-POA was significantly altered by a change in diet at 80 days of age where one-half of the males or females fed the Phyto-600 diet (from birth) were switched to the Phyto-free diet until 120 days of age. Males initially fed a Phyto-600 diet but changed to a Phyto-free diet had significantly smaller SDN-POA volumes compared to males fed the Phyto-600 diet (long-term). These data suggest that consumption of phytoestrogens via a soy diet, significantly: (1) decreases body and prostate weight, (2) delays puberty onset, and (3) alters SDN-POA volumes during adulthood.
Golinski, Alison; John-Alder, Henry; Kratochvíl, Lukáš
2011-01-01
Male sexual behavior depends on gonadal androgens in species of all major vertebrate lineages, including reptiles. However, male sexual behavior includes distinct appetitive and consummatory phases, typically denoted as courtship and mounting, with potentially different hormonal control. Different proximate controls of courtship versus mounting could enable disconnected evolutionary losses and gains of various aspects of male sexual behavior. Male courtship display, which is activated by testosterone (T) in many species, is an ancestral trait in the lizard family Eublepharidae. However, Coleonyx elegans (Yucatan Banded Gecko) lost the courtship display, while retaining a highly simplified male sexual behavior that involves only mounting for copulation. We performed surgical manipulations (castration with and without T replacement in adult males; implantation of adult females with exogenous T) to investigate hormonal mechanisms involved in this evolutionary novelty. Our results indicate that the expression of simplified sexual behavior in C. elegans does not require elevated circulating levels of T, a finding that is previously unreported in lizards. In females, however, exogenous T induced male-like mounting. Thus, the mounting phase of sexual behavior is not activated by T in the traditional sense of this term but probably requires post-natal, maturational organization (if not periodic reorganization) by androgens. We conclude that the simplification of male sexual behavior and its independence from elevated levels of circulating androgens in C. elegans evolved via 1) evolutionary loss of the androgen-activated courtship display and 2) retention of the mounting phase, which has a longer "functional memory" for the effects of androgenic steroids. Copyright © 2010 Elsevier Inc. All rights reserved.
Xiong, Weixi; Lin, Ying; Xu, Lili; Tamadon, Amin; Zou, Shien; Tian, Fubo; Shao, Ruijin; Li, Xin; Feng, Yi
2017-02-13
MicroRNAs (miRNAs) regulate the expression of genes involved in various cellular functions related to metabolism, inflammation, and reproduction. This study evaluated the effects of sex hormones and obesity on the expression of circulating miR-23a and miR-23b in women with polycystic ovary syndrome (PCOS) and healthy women. Serum sex hormones concentrations and body mass index (BMI) were measured in 18 women with PCOS and in 30 healthy women from the East China area and these measurements were correlated with serum miR-23a/b levels. The effect of miR-23a and miR-23b risk factors on occurrence of PCOS and predisposing factors of PCOS on these miRNA expressions were evaluated. The expressions of miR-23a/b were significantly lower in the women with PCOS than the normal women, and the expression levels of miR-23a/b were positively correlated with each other in the normal women (p = 0.001) but not in the women with PCOS (p > 0.05). In the women with PCOS, miR-23a was positively correlated with BMI (p = 0.03). However, no correlations were found between the levels of miR-23a/b and the sex hormones in the normal and PCOS women. On the other hand, without considering the presence or absence of PCOS, increase in BMI had a positive effect on the levels of circulating miR-23b; while testosterone had negative effects on the levels of circulating miR-23a. Furthermore, the likelihood of women with PCOS decreased by 0.01-fold for every 1 fold increase of miR-23a expression. Both reduced levels and discordance between the expressions of miR-23a/b were observed in the women with PCOS and miR-23a/b were affected from testosterone and BMI, reversely. Therefore, miR-23a alteration in contrast with miR-23b is a better indicator for evaluation of PCOS than the miR-23b.
Histopathologic and metabolic effect of ursodeoxycholic acid treatment on PCOS rat model.
Gozukara, Ilay; Dokuyucu, Recep; Özgür, Tümay; Özcan, Oguzhan; Pınar, Neslihan; Kurt, Raziye Keskin; Kucur, Suna Kabil; Dolapçı, Kenan
2016-06-01
The aim of this study was to determine the effect of ursodeoxycholic acid (UDCA) treatment on a polycystic ovary syndrome (PCOS) rat model. Thirty-two female Wistar-Albino rats were randomly divided into four groups as follows - group 1: sham group (n: 8), group 2: letrozole-induced PCOS group (n: 8), group 3: letrozole-induced PCOS plus metformin-treated (500 mg/kg) group (n: 8) and group 4: letrozole-induced PCOS plus UDCA (150 mg/kg)-treated group (n: 8). Histopathologic examination of the ovaries, circulating estrone (E1), estradiol (E2), testosterone, androstenedione, glucose, insulin and lipid profiles were evaluated. Histopathologic examination results revealed that groups 3 and 4 had significantly lower cystic and atretic follicles compared to group 2. Besides, group 4 had significantly higher antral follicles than group 2 (8.5 ± 2.9 versus 5.4 ± 1.1; p: 0.001). Furthermore, total testosterone (4.9 ± 2.8 versus 8.8 ± 2.9; p= 0.004) and insulin levels were significantly lower in group 4 compared to group 2 (1.7 ± 0.08 versus 2.1 ± 0.5; p = 0.02). However, lipid parameters, E1, E2, glucose and HOMA-IR were comparable between the groups. Our study results demonstrated that UDCA therapy improves ovarian morphology and decreases total testosterone and insulin levels.
Physiological levels of testosterone kill salmonid leukocytes in vitro
Slater, C.H.; Schreck, C.B.
1997-01-01
Adult spring chinook salmon (Oncorhynchus tshawytscha) elaborate high plasma concentrations of testosterone during sexual maturation, and these levels of testosterone have been shown to reduce the salmonid immune response in vitro. Our search for the mechanism of testosterone's immunosuppressive action has led to the characterization of an androgen receptor in salmonid leukocytes. In the present study we examined the specific effects that testosterone had on salmonid leukocytes. Direct counts of viable leukocytes after incubation with and without physiological levels of testosterone demonstrate a significant loss of leukocytes in cultures exposed to testosterone. At least 5 days of contact with testosterone was required to produce significant immunosuppression and addition of a 'conditioned media' (supernatant from proliferating lymphocytes not exposed to testosterone) did not reverse the immunosuppressive effects of testosterone. These data lead us to conclude that testosterone may exert its immunosuppressive effects by direct action on salmonid leukocytes, through the androgen receptor described, and that this action leads to the death of a significant number of these leukocytes.
Testosterone levels in suicide attempters with bipolar disorder
Sher, Leo; Grunebaum, Michael F.; Sullivan, Gregory M.; Burke, Ainsley K.; Cooper, Thomas B.; Mann, J. John; Oquendo, Maria A.
2013-01-01
Objective The best known neurobehavioral effects of testosterone are on sexual function and aggression. However, testosterone and other androgens may be involved in the pathophysiology of mood disorders and suicidal behavior. This is the first study to examine whether there is a relation between testosterone levels and clinical parameters in bipolar suicide attempters. Methods Patients with a DSM-IV diagnosis of a bipolar disorder (16 males and 51 females), in a depressive or mixed episode with at least one past suicide attempt were enrolled. Demographic and clinical parameters, including lifetime suicidal behavior, were assessed and recorded. Plasma testosterone was assayed using a double antibody radioimmunoassay procedure. Results The number of major depressive episodes, the maximum lethality of suicide attempts, and the testosterone levels were higher in men compared to women. Current suicidal ideation scores were higher in women compared to men. Controlling for sex, we found that testosterone levels positively correlated with the number of manic episodes and the number of suicide attempts. Conclusion Our findings are consistent with previous observations of the association between testosterone levels and parameters of mood and behavior. This study suggests that testosterone levels may be related to the course of bipolar disorder and suicidal behavior. Further studies of the role of testosterone in the neurobiology of mood disorders and suicidal behavior are merited. PMID:22858352
Krysiak, Robert; Kowalska, Beata; Szkróbka, Witold; Okopień, Bogusław
2016-02-01
In the light of recent studies, macroprolactinemia seems to occur much more frequently than previously thought. In women, oral contraceptive pills exhibit a stimulatory effect on macroprolactin production. No previous study has investigated macroprolactin levels in androgen-treated hypogonadal men. We studied 10 men with isolated macroprolactinemia and 14 men with normal prolactin levels who because of late-onset hypogonadism were treated with intramuscular testosterone enanthate. Serum prolactin, macroprolactin content, serum testosterone and gonadotropin levels were assessed at baseline and after 4 months of therapy. Although baseline levels of testosterone and gonadotropins were similar in men with and without macroprolactinemia, clinical symptoms were more severe in patients with elevated big-big prolactin levels. As expected, testosterone treatment increased serum testosterone, slightly reduced serum gonadotropins, as well as improved clinical condition in both patients with and without macroprolactinemia, with no difference between the groups. However, testosterone therapy did not affect serum prolactin and macroprolactin content, even after replacing intramuscular testosterone enanthate with oral testosterone undecanoate. Our results suggest a negligible effect of testosterone replacement on macroprolactin levels in macroprolactinemic men with late-onset hypogonadism. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.
The "trouble" with salivary testosterone.
Granger, Douglas A; Shirtcliff, Elizabeth A; Booth, Alan; Kivlighan, Katie T; Schwartz, Eve B
2004-11-01
In a series of studies, we identify several specific issues that can limit the value of integrating salivary testosterone in biosocial research. Salivary testosterone measurements can be substantially influenced during the process of sample collection, are susceptible to interference effects caused by the leakage of blood (plasma) into saliva, and are sensitive to storage conditions when samples have been archived. There are gender differences in salivary testosterone levels and variance, the serum-saliva association, the relationship of salivary testosterone to age and pubertal development, and the stability of individual differences in salivary testosterone levels over time. The findings have important implications at several levels of analysis for research that aims to test biosocial models of testosterone--behavior relationships. Recommendations are provided to steer investigators around these "troubles" with salivary testosterone.
Lee, Sanghoo; Kwon, Soonho; Shin, Hye-Jin; Park, Jimyeong; Lim, Hwan-Sub; Lee, Kyoung-Ryul; Kim, Young-Jin
2010-11-01
Salivary testosterone levels in Korean adults were quantitatively measured for the first time by liquid chromatography-electrospray-tandem mass spectrometry (LC ESI MS/MS). Salivary testosterone was separated on a multiple reaction monitoring (MRM) chromatogram within 7 min. The LC ESI MS/MS assay was validated over the linearity range of 0.01-2.00 ng/ml (r=0.99987) using testosterone-d(3) as an internal standard. The lower limit of quantification (LOQ) was 0.01 ng/ml. The intra- and inter-assay precisions were 1.54% to 4.09% and 0.96% to 4.29%, respectively. The mean recovery was 93.32% (range 88.43-98.05%). The validated assay was then applied to measure the salivary testosterone levels of Korean adults. In men, the salivary testosterone level collected between 9:00-11:00 am was approximately 2.8 times higher than that in women (P < 0.0001). Salivary testosterone levels in both sexes negatively correlated with age. The present assay would also be useful in measuring salivary testosterone levels in clinical laboratories.
Alzheimer, mitochondria and gender.
Grimm, Amandine; Mensah-Nyagan, Ayikoe Guy; Eckert, Anne
2016-08-01
Epidemiological studies revealed that two-thirds of Alzheimer's disease (AD) patients are women and the drop of sex steroid hormones after the menopause has been proposed to be one risk factor in AD. Similarly, the decrease of circulating testosterone levels with aging may also increase the risk of AD in men. Studies attest the neuroprotective effects of sex hormones in animal models of AD, but clinical trial data remain controversial. Here, we discuss the implication of mitochondria in gender differences observed in AD patients and animal models of AD. We summarize the role of mitochondria in aging and AD, pointing to the potential correlation between the loss of sex hormones and changes in the brain redox status. We discuss the protective effects of the sex hormones, estradiol, progesterone and testosterone with a specific focus on mitochondrial dysfunction in AD. The understanding of pathological processes linking the loss of sex hormones with mitochondrial dysfunction and mechanisms that initiate the disease onset may open new avenues for the development of gender-specific therapeutic approaches. Copyright © 2016. Published by Elsevier Ltd.
Gooding, Meredith P; Wilson, Vickie S; Folmar, Leroy C; Marcovich, Dragoslav T; LeBlanc, Gerald A
2003-01-01
Imposex, the development of male sex characteristics by female gonochoristic snails, has been documented globally and is causally associated with exposure to the ubiquitous environmental contaminant tributyltin (TBT). Elevated testosterone levels in snails also are associated with TBT, and direct exposure to testosterone has been shown to cause imposex. We discovered previously that the mud snail (Ilyanassa obsoleta)biotransforms and retains excess testosterone primarily as fatty acid esters. The purpose of this study was to determine whether TBT interferes with the esterification of testosterone, resulting in the elevated free (unesterified) testosterone levels associated with imposex. Exposure of snails to environmentally relevant concentrations of TBT (> or = 1.0 ng/L as tin) significantly increased the incidence of imposex. Total (free + esterified) testosterone levels in snails were not altered by TBT; however, free testosterone levels increased with increasing exposure concentration of TBT. TBT-exposed snails were given [14C
Coelingh Bennink, Herjan J T; Zimmerman, Yvette; Laan, Ellen; Termeer, Hanneke M M; Appels, Nicole; Albert, Adelin; Fauser, Bart C J M; Thijssen, Jos H H; van Lunsen, Rik H W
2017-11-01
To determine whether adding dehydroepiandrosterone to combined oral contraceptives (COCs) maintains physiological levels of free testosterone. A randomized, double-blind, placebo-controlled, two-way crossover study conducted in 81 healthy women (age range: 20-35 years; Body mass index (BMI) range: 18-35 kg/m 2 ) using oral contraceptives. Androgens, sex hormone-binding globulin (SHBG), estradiol (E2) and estrone (E1) were measured, and free testosterone and the free testosterone index were calculated. Subjects discontinued oral contraceptive use for at least one menstrual cycle before being randomized to receive five cycles of ethinyl estradiol (EE) combined with either levonorgestrel (EE/LNG group) or drospirenone (EE/DRSP group) together with either dehydroepiandrosterone (DHEA) (50 mg/day orally) or placebo. Subsequently, all subjects crossed over to the other treatment arm for an additional five cycles. Both COCs decreased the levels of all androgens measured. Significant decreases (p<.05) were found with EE/LNG and EE/DRSP for total testosterone (54.5% and 11.3%, respectively) and for free testosterone (66.8% and 75.6%, respectively). Adding DHEA to the COCs significantly increased all androgens compared to placebo. Moreover, including DHEA restored free testosterone levels to baseline values in both COC groups and total testosterone levels to baseline in the EE/LNG group and above baseline in the EE/DRSP group. SHBG concentrations were significantly higher with EE/DRSP compared to EE/LNG (p<.0001). The addition of DHEA did not affect the levels of SHBG. Taking COCs reduces total and free testosterone levels and increases SHBG concentrations. By coadministration with DHEA, physiological levels of total and free testosterone are restored while using EE/LNG. With EE/DRSP, only the free testosterone level is normalized by DHEA coadministration. A daily oral dose of 50-mg DHEA maintains physiological free and total testosterone levels in women who are using an EE/LNG-containing COC. Copyright © 2016 Pantarhei Bioscience. Published by Elsevier Inc. All rights reserved.
Rovira-Llopis, Susana; Bañuls, Celia; de Marañon, Aranzazu M; Diaz-Morales, Noelia; Jover, Ana; Garzon, Sandra; Rocha, Milagros; Victor, Victor M; Hernandez-Mijares, Antonio
2017-07-01
Low testosterone levels in men are associated with type 2 diabetes and cardiovascular risk. However, the role of testosterone in mitochondrial function and leukocyte-endothelium interactions is unknown. Our aim was to evaluate the relationship between testosterone levels, metabolic parameters, oxidative stress, mitochondrial function, inflammation and leukocyte-endothelium interactions in type 2 diabetic patients. The study was performed in 280 male type 2 diabetic patients and 50 control subjects. Anthropometric and metabolic parameters, testosterone levels, reactive oxygen species (ROS) production, mitochondrial membrane potential, TNFα, adhesion molecules and leukocyte-endothelium cell interactions were evaluated. Testosterone levels were lower in diabetic patients. Total and mitochondrial ROS were increased and mitochondrial membrane potential, SOD and GSR expression levels were reduced in diabetic patients. TNFα, ICAM-1 and VCAM-1 levels, leukocyte rolling flux and adhesion were all enhanced in diabetic patients, while rolling velocity was reduced. Testosterone levels correlated negatively with glucose, HOMA-IR, HbA1c, triglycerides, nonHDL-c, ApoB, hs-CRP and AIP, and positively with HDL-c and ApoA1. The multivariable regression model showed that HDL-c, HOMA-IR and age were independently associated with testosterone. Furthermore, testosterone levels correlated positively with membrane potential and rolling velocity and negatively with ROS production, VCAM-1, rolling flux and adhesion. Our data highlight that low testosterone levels in diabetic men are related to impaired metabolic profile and mitochondrial function and enhanced inflammation and leukocyte-endothelium cell interaction, which leaves said patients at risk of cardiovascular events. Copyright © 2017 Elsevier Inc. All rights reserved.
Burns, Patrick R; Kim, Edward D; Ruff, Dustin D; Seftel, Allen D
2018-05-01
This study evaluated the effect of axillary administration of a 2% testosterone solution (Axiron ® ) in hypogonadal (HGN) men who had had a suboptimal response to treatment with a commercially available topical testosterone gel. HGN men averaging 57 years old, with a mean body mass index of 31.9 kg/m 2 and median baseline testosterone level (T-level) of 185.2 ng/dL, who had failed to reach normal T-levels with a topical testosterone gel (Androgel 1.62%, Androgel, Testim, or Fortesta) were treated with a 2% testosterone solution until T-levels reached a normal range (from ≥300 to ≤1,050 ng/dL) or for up to 9 weeks. Outcomes included the cumulative percentage of men with a serum T-level in the normal range during treatment with Axiron and improvement in symptoms of low energy level and low sexual drive. During the study, 95% of HGN men (72/78) attained a T-level in the normal range. The median T-level at endpoint was 495.7 ng/dL, a threefold increase over baseline, p < .001, 70% achieving normal T-levels within the first 2 weeks of treatment. In a post hoc analysis, all subjects with baseline body mass indexes >35 kg/m 2 ( n = 19) achieved T-levels in the normal range. Prior to treatment, over 61% of subjects (48/78) reported impairment in either energy level or sexual drive. After treatment (or testosterone normalization), energy level improved in 75% of subjects and sexual drive improved in 70%. Topical 2% testosterone solution is a safe and effective treatment for HGN men who have had a suboptimal response to previous treatment with topical testosterone gels.
ERIC Educational Resources Information Center
Archer, John
1994-01-01
Studies comparing aggressive and nonaggressive prisoners show higher testosterone levels among the former. While there is limited evidence for a strong association between aggressiveness and testosterone during adolescence, other studies indicate that testosterone levels are responsive to influences from the social environment, particularly those…
Luis, Juana; Ramírez, Lorena; Carmona, Agustín; Ortiz, Guadalupe; Delgado, Jesús; Cárdenas, René
2009-01-01
Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae). Although initially it was thought that testosterone inhibited the display of paternal behavior in males of rodents, it has been shown that in some species high testosterone levels are needed for exhibition of paternal care. In captivity, males of Volcano Mouse (Neotomodon alstoni) provide pups the same care provided by the mother, with the exception of suckling. Here we measured plasmatic testosterone concentrations 10 days after mating, five and 20 days postpartum, and 10 days after males were isolated from their families in order to determine possible changes in this hormone, associated to the presence and age of pups. Males of Volcano Mouse exhibited paternal behavior when their testosterone levels were relatively high. Although levels of this hormone did not change with the presence or pups age, males that invested more time in huddling showed higher testosterone levels. It is possible that in the Volcano Mouse testosterone modulates paternal behavior indirectly, as in the California mouse.
Seidl, Jennifer N Travis; Massman, Paul J
2015-03-01
Previous research suggests that low levels of testosterone may be associated with the development of Alzheimer disease (AD), as well as poorer performance on certain neuropsychological tests and increased risk of depression. This study utilized data from 61 nondemented older men and 68 men with probable AD. Testosterone levels did not differ between the groups. Regression analyses in men with AD revealed that testosterone levels did not significantly predict performance on neuropsychological tests or a measure of depression. Among controls, testosterone levels predicted estimated premorbid verbal IQ and performance on a verbal fluency test. Findings suggest that testosterone is not associated with most neuropsychological test performances in patients with AD. © The Author(s) 2014.
Salivary testosterone levels in men at a U.S. sex club.
Escasa, Michelle J; Casey, Jacqueline F; Gray, Peter B
2011-10-01
Vertebrate males commonly experience elevations in testosterone levels in response to sexual stimuli, such as presentation of a novel mating partner. Some previous human studies have shown that watching erotic movies increases testosterone levels in males although studies measuring testosterone changes during actual sexual intercourse or masturbation have yielded mixed results. Small sample sizes, "unnatural" lab-based settings, and invasive techniques may help account for mixed human findings. Here, we investigated salivary testosterone levels in men watching (n = 26) versus participating (n = 18) in sexual activity at a large U.S. sex club. The present study entailed minimally invasive sample collection (measuring testosterone in saliva), a naturalistic setting, and a larger number of subjects than previous work to test three hypotheses related to men's testosterone responses to sexual stimuli. Subjects averaged 40 years of age and participated between 11:00 pm and 2:10 am. Consistent with expectations, results revealed that testosterone levels increased 36% among men during a visit to the sex club, with the magnitude of testosterone change significantly greater among participants (72%) compared with observers (11%). Contrary to expectation, men's testosterone changes were unrelated to their age. These findings were generally consistent with vertebrate studies indicating elevated male testosterone in response to sexual stimuli, but also point out the importance of study context since participation in sexual behavior had a stronger effect on testosterone increases in this study but unlike some previous human lab-based studies.
Hormone Treatment and Muscle Anabolism during Aging: Androgens
Dillon, E. Lichar; Durham, William J.; Urban, Randall J.; Sheffield-Moore, Melinda
2010-01-01
Aging is associated with a gradual decline in circulating testosterone concentrations and decreased musculature in men. While testosterone administration is often considered when symptoms of hypogonadism are presented, the long-term effects of androgen use on muscle physiology are not yet fully understood. The definition of hypogonadism in men remains obscure but is generally indicated by total testosterone concentrations less than a threshold value of 300-500 ng/dL. Androgen replacement therapy is generally safe in men and women with low endogenous testosterone concentrations. The development of selective androgen receptor modulators (SARMs) may provide additional options in treatment of hypogonadism while lowering the potential of side effects often associated with long-term androgen use. Androgen administration, either alone or in combination with other treatments, can be successful in improving muscle mass by increasing protein anabolism and reducing protein catabolism in men and women. Further research is necessary to optimize the anabolic and anticatabolic properties of androgens for treatment and prevention of muscle loss in men and women. PMID:20452103
Liang, Jennifer J; Jolly, Divya; Chan, Kelly J; Safer, Joshua D
2018-02-01
Most transgender women depend on medical treatment alone to lower testosterone levels in order to align physical appearance with gender identity. The medical regimen in the United States typically includes spironolactone and estrogens. The purpose of this cross-sectional study was to assess the testosterone suppression achieved among transgender women treated with spironolactone and estrogens. Testosterone and estradiol levels were extracted from the electronic medical records of 98 anonymized transgender women treated with oral spironolactone and oral estrogen therapy at the Endocrinology Clinic at Boston Medical Center. Patients starting therapy required about 9 months to reach a steady-state testosterone, with significant heterogeneity of levels achieved among patients. Patients with normal body mass index (BMI) had higher testosterone levels, whereas patients with obese BMI had lower testosterone levels throughout treatment. Stratification of patients by age or spironolactone dosage revealed no significant difference in testosterone levels achieved. At steady state, patients in the highest suppressing quartile were able to achieve testosterone levels of 27 ng/dL, with a standard deviation of 21 ng/dL. Measured serum estradiol levels did not change over time and did not correlate with dosage of estradiol administered. Among a cohort of transgender women treated with spironolactone and estrogen, the highest suppressing quartile could reliably achieve testosterone levels in the female range at virtually all times. The second highest suppressing quartile could not achieve female levels but remained below the male range virtually all of the time. One quartile was unable to achieve any significant suppression. BMC = Boston Medical Center BMI = body mass index CPY = cyproterone acetate LC-MS/MS = liquid chromatography-tandem mass spectrometry Q = quartile.
Zhou, Cindy Ke; Stanczyk, Frank Z; Hafi, Muhannad; Veneroso, Carmela C; Lynch, Barlow; Falk, Roni T; Niwa, Shelley; Emanuel, Eric; Gao, Yu-Tang; Hemstreet, George P; Zolfghari, Ladan; Carroll, Peter R; Manyak, Michael J; Sesterhenn, Isabell A; Levine, Paul H; Hsing, Ann W; Cook, Michael B
2017-12-01
Prospective cohort studies of circulating sex steroid hormones and prostate cancer risk have not provided a consistent association, despite evidence from animal and clinical studies. However, studies using male pattern baldness as a proxy of early-life or cumulative androgen exposure have reported significant associations with aggressive and fatal prostate cancer risk. Given that androgens underlie the development of patterned hair loss and chest hair, we assessed whether these two dermatological characteristics were associated with circulating and intraprostatic concentrations of sex steroid hormones among men diagnosed with localized prostate cancer. We included 248 prostate cancer patients from the NCI Prostate Tissue Study, who answered surveys and provided a pre-treatment blood sample as well as fresh frozen adjacent normal prostate tissue. Male pattern baldness and chest hair density were assessed by trained nurses before surgery. General linear models estimated geometric means and 95% confidence intervals (95%CIs) of each hormone variable by dermatological phenotype with adjustment for potential confounding variables. Subgroup analyses were performed by Gleason score (<7 vs ≥7) and race (European American vs. African American). We found strong positive associations of balding status with serum testosterone, dihydrotestosterone (DHT), estradiol, and sex hormone-binding globulin (SHBG), and a weak association with elevated intraprostatic testosterone. Conversely, neither circulating nor intraprostatic sex hormones were statistically significantly associated with chest hair density. Age-adjusted correlation between binary balding status and three-level chest hair density was weak (r = 0.05). There was little evidence to suggest that Gleason score or race modified these associations. This study provides evidence that balding status assessed at a mean age of 60 years may serve as a clinical marker for circulating sex hormone concentrations. The weak-to-null associations between balding status and intraprostatic sex hormones reaffirm differences in organ-specific sex hormone metabolism, implying that other sex steroid hormone-related factors (eg, androgen receptor) play important roles in organ-specific androgenic actions, and that other overlapping pathways may be involved in associations between the two complex conditions. © 2017 Wiley Periodicals, Inc.
Correlation Between Personality Traits and Testosterone Concentrations in Healthy Population.
Tajima-Pozo, Kazuhiro; Bayón, Camila; Díaz-Marsá, Marina; Carrasco, Jose Luis
2015-01-01
High plasma testosterone levels have been associated with aggression, sexual behaviour and social status. The aim of this paper was to study the correlation between basal plasma testosterone levels and personality variables in healthy participants. Fifty-four participants were randomly enrolled into this study. Basal plasma testosterone levels were measured between 8:30 am and 10 am. After 24 hours of blood drawing, each subject completed personality questionnaires. Positive correlation between basal plasma testosterone levels and anti-social personality traits in both genders was observed (r = 0.336 and P < 0.018). Also, a positive correlation was observed between basal plasmatestosterone levels and criminal thinking traits (r = 0. 376, P < 0.05) and Millon compulsive (r = 0.386, P < 0.010) in both genders. In female participants, a positive correlation between basal plasmatestosterone levels and psychoticism (r = 0. 25, P < 0.019) and Cloninger AUTO TCI (r = 0.507, P < 0.004) was observed. In males participants positive correlation between baseline plasmatic Testosterone levels and Millon Antisocial trait (r = 0. 544, P < 0.19) and Millon Hypomania trait (r = 0. 485, P < 0.41) and Millon Drug Abuse trait (r = 0.632, P < 0.05) was reported. Our results suggest gender differences in clinical and personality variables related with basal plasma testosterone level. In men, high plasma testosterone levels were associated with clinical traits, substance abuse and hypomania. Women with higher basal testosterone levels showed higher scores on personality self-direction traits.
Loughlin, Kevin R
2016-11-01
The controversy surrounding the relationship between testosterone and prostate cancer has existed for decades. The literature surrounding this topic is confusing and at times contradictory. There is no level-one quality evidence that confirms or refutes the relationship between either high or low serum testosterone levels and the subsequent development of prostate cancer. This commentary aims to review the issues involved and to provide an interpretation as to the causes of the confusion and to provide a framework for ongoing discussion and investigation. A Medline and PubMed search was conducted using search terms: testosterone levels and prostate cancer to identify pertinent literature. There is no consistent evidence that a single testosterone level is predictive of prostate cancer risk. The development of prostate cancer is a complex biologic process potentially involving genetics,dietary, life style and hormonal factors. Serum testosterone levels do not accurately reflect the internal prostatic milieu. Finally, if testosterone levels are to be considered in the etiology of prostate cancer they should be measured and interpreted on a chronic basis with multiple measurements over a period of years. Copyright © 2016 Elsevier Inc. All rights reserved.
Endendijk, Joyce J; Hallers-Haalboom, Elizabeth T; Groeneveld, Marleen G; van Berkel, Sheila R; van der Pol, Lotte D; Bakermans-Kranenburg, Marian J; Mesman, Judi
2016-04-01
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. Copyright © 2016 Elsevier Inc. All rights reserved.
Wallace, E M; Gow, S M; Wu, F C
1993-07-01
Sex-steroid based male contraceptive regimes induce azoospermia in only 40-70% of Caucasian men. The reason(s) why the remainder maintains a low level of spermatogenesis (oligozoospermia) despite gonadotrophin suppression is unclear. In order to improve our understanding of this phenomenon, we examined the changes in sperm density and plasma LH, FSH, testosterone (T), oestradiol (E2), and inhibin (IN) in 28 normal men who received 200 mg testosterone enanthate (TE) im weekly during a male contraceptive efficacy trial. Gonadotrophins were measured by an ultrasensitive time-resolved immunofluorometric assay (DELFIA) with a sensitivity of 0.04 U/L, to determine the adequacy of suppression. Seventeen of the 28 men achieved azoospermia; the other 11 remained oligozoospermic (sperm density 3.3-4.7 x 10(6)/mL) after 6 months of TE exposure. Azoospermic subjects displayed a more rapid decline in sperm density, a significant difference being apparent by 5 weeks after starting TE. During TE treatment, both LH and FSH were consistently suppressed to below the limits of detection, whereas there was a 2.5-fold rise in T and E2 with a similar decrease in IN. There were no consistent differences in any of these hormone concentrations between the azoospermic and oligozoospermic groups. Recovery of sperm density to baseline levels or above 20 x 10(6)/mL was significantly slower in the azoospermic group. During the recovery phase, the azoospermic men exhibited significantly higher LH and FSH levels compared to baseline and to the oligozoospermic subjects even though no differences in circulating T, E2, or IN were observed. We conclude that incomplete gonadotrophin suppression or differences in sex steroid or inhibin levels are unlikely to be responsible for the maintenance of minor degrees of spermatogenesis in some men during TE administration. The rebound rise in gonadotrophins in azoospermic but not oligozoospermic responders during recovery may reflect a more profound degree of spermatogenic suppression in the former group.
No evidence for the immunocompetence handicap hypothesis in male humans.
Nowak, Judyta; Pawłowski, Bogusław; Borkowska, Barbara; Augustyniak, Daria; Drulis-Kawa, Zuzanna
2018-05-09
The observations that testosterone might be immunosuppressive, form the basis for the immunocompetence handicap hypothesis (ICHH). According to ICHH only high-quality individuals can maintain high levels of testosterone and afford the physiological cost of hormone-derived immunosuppression. The animal and human studies that attempted to support the ICHH by precisely defined impairment of immunity associated with high testosterone levels are inconclusive. Furthermore, human studies have used only selected immune functions and varying testosterone fractions. This is the first study examining the relationship between multiple innate and adaptive immunity and serum levels of free testosterone, total testosterone, DHT and DHEA in ninety-seven healthy men. Free testosterone and marginally DHT levels were positively correlated with the strength of the influenza post-vaccination response. Total testosterone and DHEA showed no immunomodulatory properties. Our findings did not support ICHH assumptions about immunosuppressive function of androgens. In the affluent society studied here, men with higher levels of free testosterone could afford to invest more in adaptive immunity. Since the hormone-immune relationship is complex and may depend on multiple factors, including access to food resources, androgens should be treated as immunomodulators rather than implicit immunosuppressants.
Lack of evidence for meteorological effects on infradian dynamics of testosterone
NASA Astrophysics Data System (ADS)
Celec, Peter; Smreková, Lucia; Ostatníková, Daniela; Čabajová, Zlata; Hodosy, Július; Kúdela, Matúš
2009-09-01
Climatic factors are known to influence the endocrine system. Previous studies have shown that circannual seasonal variations of testosterone might be partly explained by changes in air temperature. Whether infradian variations are affected by meteorological factors is unknown. To analyze possible effects of meteorological parameters on infradian variations of salivary testosterone levels in both sexes, daily salivary testosterone levels were measured during 1 month in 14 men and 17 women. A correlation analysis between hormonal levels and selected meteorological parameters was performed. The results indicate that high testosterone levels are loosely associated with cold, sunny and dry weather in both sexes. However, only the correlations between testosterone and air temperature (men) and actual cloudiness (women) were statistically significant ( p < 0,05). Although some correlations reached the level of statistical significance, the effects of selected meteorological parameters on salivary testosterone levels remain unclear. Further longer-term studies concentrating on air temperature, cloudiness and average relative humidity in relation to the sex hormone axis are needed.
Lin, Eleanor; McCabe, Elizabeth; Newton-Cheh, Christopher; Bloch, Kenneth; Buys, Emmanuel; Wang, Thomas; Miller, Karen K.
2011-01-01
Objective To investigate whether testosterone administration alters natriuretic peptide levels in women. Design Three-month, double-blind, randomized, placebo-controlled study. Setting Clinical research center. Patients 51 women with hypoandrogenemia due to hypopituitarism. Intervention Transdermal testosterone (300 mcg daily) or placebo patch. Main Outcome Measure N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. Results NT-proBNP levels decreased in the transdermal testosterone group compared with placebo over three months (p = 0.009). The difference between groups remained significant after controlling for baseline age, systolic blood pressure, body mass index, and homeostasis model of assessment-insulin resistance (p = 0.008). Change in NT-proBNP over three months was inversely associated with change in free testosterone levels (ρ = −0.41, p = 0.01). Conclusions Testosterone administration to women results in decreased natriuretic peptide levels, suggesting that testosterone may be an inverse regulator of the natriuretic peptide system. Clinical Trials Registration Number NCT00027430 PMID:22137497
Martínez-Padilla, J; Pérez-Rodríguez, L; Mougeot, F; Ludwig, S; Redpath, S M
2014-05-01
In a reliable signalling system, individual quality is expected to mediate the costs associated with ornamental displays, with relatively lower costs being paid by individuals of higher quality. These relative costs should depend not only on individual quality, but also on levels of intra-sexual competition. We explored the current and delayed effects that testosterone implants have on bird ornamentation in populations with contrasted population densities, as a proxy for intra-sexual competition. In a replicated experiment, we manipulated testosterone in 196 yearling male red grouse Lagopus lagopus scoticus in autumn in populations of high and low levels of intra-sexual competition. Males were assigned to one of three exogenous testosterone (T) treatments: empty implants (T0), small T implants (T1) or larger T implants (T2). We monitored subsequent changes in testosterone levels, ornament size and carotenoid-based colouration, carotenoid levels and body condition from autumn to spring. Testosterone implants increased testosterone levels, comb redness and comb size, and decreased body condition but these effects depended on levels of intra-sexual competition. Specifically, T2-implanted birds increased testosterone levels and comb size more, and reduced body condition more, in populations where intra-sexual competition was low. In the following spring, testosterone levels of T2-treated birds kept increasing in populations where intra-sexual competition was high but not in populations where intra-sexual competition was low. Our results highlight that levels of intra-sexual competition alter the relationship between testosterone levels and ornament expression, influencing their condition-dependence; they also indicate that the outcome of standard hormone manipulation conducted in free-living animals vary depending on the population context. Copyright © 2014 Elsevier Inc. All rights reserved.
Patterns of testosterone in three Nearctic-Neotropical migratory songbirds during spring passage.
Covino, Kristen M; Morris, Sara R; Moore, Frank R
2015-12-01
Preparation for breeding may overlap extensively with vernal migration in long-distance migratory songbirds. Testosterone plays a central role in mediating this transition into breeding condition by facilitating changes to physiology and behavior. While changes in testosterone levels are well studied in captive migrants, these changes are less well known in free-living birds. We examined testosterone levels in free-living Nearctic-Neotropical migrants of three species during their vernal migration. Testosterone levels increased during the migratory period in males of all three species but significantly so in only two. Testosterone levels in females remained the same throughout their migration. Our results support the extensive overlap between vernal migration and breeding preparation in male songbirds. The pattern of testosterone changes during vernal migration is far from clear in females. Copyright © 2015 Elsevier Inc. All rights reserved.
Sertoli cell markers in the diagnosis of paediatric male hypogonadism.
Grinspon, Romina P; Loreti, Nazareth; Braslavsky, Débora; Bedecarrás, Patricia; Ambao, Verónica; Gottlieb, Silvia; Bergadá, Ignacio; Campo, Stella M; Rey, Rodolfo A
2012-01-01
During childhood, the pituitary-testicular axis is partially dormant: testosterone secretion decreases following a drop in luteinising hormone levels; follicle-stimulating hormone (FSH) levels also go down. Conversely, Sertoli cells are most active, as revealed by the circulating levels of anti-Müllerian hormone (AMH) and inhibin B. Therefore, hypogonadism can best be evidenced, without stimulation tests, if Sertoli cell function is assessed. Serum AMH is high from fetal life until mid-puberty. Testicular AMH production increases in response to FSH and is potently inhibited by androgens. Inhibin B is high in the first years of life, then decreases partially while remaining clearly higher than in females, and increases again at puberty. Serum AMH and inhibin B are undetectable in anorchid patients. In primary or central hypogonadism affecting the whole gonad established in fetal life or childhood, all testicular markers are low. Conversely, when hypogonadism only affects Leydig cells, serum AMH and inhibin B are normal. In males of pubertal age with central hypogonadism, AMH and inhibin B are low. Treatment with FSH provokes an increase in serum levels of both Sertoli cell markers, whereas human chorionic gonadotrophin (hCG) administration increases testosterone levels. In conclusion, measurement of serum AMH and inhibin B is helpful in assessing testicular function, without need for stimulation tests, and orientates the aetiological diagnosis of paediatric male hypogonadism.
Ford, Andrew H; Yeap, Bu B; Flicker, Leon; Hankey, Graeme J; Chubb, S A Paul; Handelsman, David J; Golledge, Jonathan; Almeida, Osvaldo P
2016-02-01
Depression in older men has been associated with low circulating testosterone concentration but data from prospective studies are limited. We conducted a prospective longitudinal study in a community representative cohort of 3179 older men free of clinically significant depressive symptoms at baseline. The main objective of this study was to determine if low serum testosterone, dihydrotestosterone and estradiol concentrations are associated with the development of depressive symptoms. Incident depression was assessed with the Patient Health Questionnaire and via an electronic health record database (The West Australian Data Linkage System). The main exposures of interest were serum testosterone, dihydrotestosterone and estradiol measured by liquid chromatography-mass spectrometry and calculated free testosterone in baseline blood samples (collected between 2001 and 2004). One hundred and thirty five men (4.2%) developed depression over a median follow up time of 9.4 years (range 8.4-10.9). Men with incident depression were older (median age 77.7 vs 76.1 years, z=-3.82, p=0<0.001) and were more likely to have cardiovascular disease (43.0% vs 32.6%, χ(2)=6.32, p=0.012) and diabetes (22.2% vs 13.2%, χ(2)=8.95, p=0.003). Low serum total testosterone (<6.4 nmol/L) was associated with incident depression (HR 2.07, 95%CI 1.17-3.68) and this remained significant after adjustment for relevant potential confounding factors (HR 1.86, 95%CI 1.05-3.31). Low serum dihydrotestosterone, estradiol and calculated free testosterone were not associated with risk of depression. Low serum total testosterone, but not calculated free testosterone, was associated with incident depression in this sample of older men. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
Morote, Juan; Comas, Inma; Planas, Jacques; Maldonado, Xavier; Celma, Ana; Placer, José; Ferrer, Roser; Carles, Joan; Regis, Lucas
2018-04-01
Serum testosterone measurement is recommended to assess the efficacy of androgen deprivation therapy (ADT) and to diagnose castration resistance in patients with prostate cancer (PCa). Currently, the accepted castrate level of serum testosterone is 50 ng/dL. Liquid chromatography and tandem mass spectrometry (LC MSMS) is the appropriate method to measure testosterone, especially at low levels. However, worldwide, chemiluminescent assays (CLIAs) are used in clinical laboratories, despite their lack of accuracy and reproducibility, because they are automatable, fast, sensitive, and inexpensive. We compared serum testosterone levels measured using LC MSMS and CLIAs in 126 patients with PCa undergoing luteinizing hormone-releasing hormone (LHRH) agonist therapy. The median serum testosterone level was 14.0 ng/dL (range, 2.0-67.0 ng/dL) with LC MSMS and 31.9 ng/dL (range, 10.0-91.6 ng/dL) with CLIA (P < .001). The serum testosterone levels, measured using LC MSMS, were < 20 ng/dL in 83 patients (65.9%), 20 to 50 ng/dL in 40 (31.7%), and > 50 ng/dL in 3 patients (2.4%). These ranges were found in 34 (27%), 72 (57.1%), and 20 (15.9%) patients when testosterone was measured using CLIA (P < .001). The castrate level of serum testosterone using LC MSMS and CLIA was 39.8 ng/dL (95% confidence interval [CI], 37.1-43.4 ng/dL) and 66.5 ng/dL (95% CI, 62.3-71.2 ng/dL), respectively. We found that CLIA overestimated the testosterone levels in PCa patients undergoing LHRH agonist therapy. Thus, the castration level was incorrectly considered inadequate with CLIA in almost 15% of patients. The true castration level of serum testosterone using an appropriate method is < 50 ng/dL. Copyright © 2017 Elsevier Inc. All rights reserved.
Sexual differentiation of the brain occurs during late gestation through the early postnatal period. The development of the phenotypical male brain is dependent on the aromatization of circulating testosterone to estradiol. Exposure to endocrine disrupting chemicals (EDCs) duri...
Identification of neural biomarkers of altered sexual differentiation following gestational exposure
Sexual differentiation of the brain occurs during late gestation through the early postnatal period. The development of the phenotypical male brain is dependent on the aromatization of circulating testosterone to estradiol. Exposure to endocrine disrupting chemicals (EDCs) during...
Sexual differentiation of the brain occurs during late gestation through the early postnatal period. The development of the phenotypical male brain is dependent on the aromatization of circulating testosterone to estradiol. Exposure to endocrine disrupting chemicals (EDCs) duri...
Growing Up Or Growing Old? Cellular Aging Linked With Testosterone Reactivity To Stress In Youth
Drury, Stacy S.; Shirtcliff, Elizabeth A.; Shachet, Andrew; Phan, Jenny; Mabile, Emily; Brett, Zoë H.; Wren, Michael; Esteves, Kyle; Theall, Katherine P.
2014-01-01
Background Given the established relation between testosterone and aging in older adults, we tested whether buccal telomere length (TL), an established cellular biomarker of aging, was associated with testosterone levels in youth. Methods Children, mean age 10.2 years, were recruited from the greater New Orleans area and salivary testosterone was measured during both an acute stressor and diurnally. Buccal TL was measured using monochrome multiplex quantitative real-time PCR (MMQ-PCR). Testosterone and telomere length data was available on 77 individuals. The association between buccal TL and testosterone was tested using multivariate Generalized Estimating Equations (GEE) to account for clustering of children within families. Results Greater peak testosterone levels (β=-0.87, p < 0.01) and slower recovery (β=-0.56, p < 0.01) and reactivity (β = -1.22, p < 0.01) following a social stressor were significantly associated with shorter buccal TL after controlling for parental age at conception, child age, sex, sociodemographic factors and puberty. No association was initially present between diurnal measurements of testosterone or morning basal testosterone levels and buccal TL. Sex significantly moderated the relation between testosterone reactivity and buccal TL. Conclusions The association between testosterone and buccal TL supports gonadal maturation as a developmentally sensitive biomarker of aging within youth. As stress levels of testosterone were significantly associated with buccal TL, these findings are consistent with the growing literature linking stress exposure and accelerated maturation. The lack of association of diurnal testosterone or morning basal levels with buccal TL bolsters the notion of a shared stress-related maturational mechanism between cellular stress and the hypothalamic pituitary gonadal (HPG) axis. These data provide novel evidence supporting the interaction of aging, physiologic stress and cellular processes as an underlying mechanism linking negative health outcomes and early life stress. PMID:25010187
Padmanabhan, Vasantha; Sarma, Hiren N.; Savabieasfahani, Mozhgan; Steckler, Teresa L.; Veiga-Lopez, Almudena
2014-01-01
The inappropriate programming of developing organ systems by exposure to excess native or environmental steroids, particularly the contamination of our environment and our food sources with synthetic endocrine disrupting chemicals that can interact with steroid receptors, is a major concern. Studies with native steroids have found that in utero exposure of sheep to excess testosterone, an estrogen precursor, results in low birth weight offspring and leads to an array of adult reproductive / metabolic deficits manifested as cycle defects, functional hyperandrogenism, neuroendocrine / ovarian defects, insulin resistance, and hypertension. Furthermore, the severity of reproductive dysfunction is amplified by excess postnatal weight gain. The constellation of adult reproductive and metabolic dysfunction in prenatal testosterone-treated sheep is similar to features seen in women with polycystic ovary syndrome. Prenatal dihydrotestosterone treatment failed to result in similar phenotype suggesting that many effects of prenatal testosterone excess are likely facilitated via aromatization to estradiol. Similarly, exposure to environmental steroid imposters such as bisphenol A (BPA) and methoxychlor (MXC) from days 30-90 of gestation had long-term but differential effects. Exposure of sheep to BPA, which resulted in maternal levels of 30-50 ng/ml BPA, culminated in low birth-weight offspring. These female offspring were hypergonadotropic during early postnatal life and characterized by severely dampened preovulatory LH surges. Prenatal MXC-treated females had normal birth weight and manifested delayed but normal amplitude LH surges. Importantly, the effects of BPA were evident at levels, which approximated twice the highest levels found in human maternal circulation of industrialized nations. These findings provide evidence in support of developmental origin of adult reproductive and metabolic diseases and highlight the risk posed by exposure to environmental endocrine disrupting chemicals. PMID:20070410
Chin, Kok-Yong; Gengatharan, Dhivakaran; Mohd Nasru, Fadlin Sakina; Khairussam, Rehan Amalia; Ern, Sherlyn Lai Hui; Aminuddin, Siti Aina Wahidah; Ima-Nirwana, Soelaiman
2016-01-01
Osteoporosis reduces the skeletal strength and increases the risk for fracture. It is an underdiagnosed disease in men. Annatto tocotrienol has been shown to improve bone structural indices and increase expression of bone formation genes in orchidectomized rats. This study aimed to evaluate the effects of annatto tocotrienol on biomechanical strength and calcium content of the bone in orchidectomized rats. Thirty three-month-old male Sprague-Dawley rats were randomly assigned to five groups. The baseline control (BC) group was sacrificed at the onset of the study. The sham-operated group (SHAM) received olive oil (the vehicle of tocotrienol) orally daily and peanut oil (the vehicle of testosterone) intramuscularly weekly. The remaining rats were orchidectomized and treated with three different regimens, i.e., (1) daily oral olive oil plus weekly intramuscular peanut oil injection; (2) daily oral annatto tocotrienol at 60 mg/kg plus weekly intramuscular peanut oil injection; (3) daily oral olive oil plus weekly intramuscular testosterone enanthate injection at 7 mg/kg. Blood, femur and tibia of the rats were harvested at the end of the two-month treatment period for the evaluation of serum total calcium and inorganic phosphate levels, bone biomechanical strength test and bone calcium content. Annatto-tocotrienol treatment improved serum calcium level and tibial calcium content (p < 0.05) but it did not affect femoral biomechanical strength (p > 0.05). In conclusion, annatto-tocotrienol at 60 mg/kg augments bone calcium level by preventing calcium mobilization into the circulation. A longer treatment period is needed for annatto tocotrienol to exert its effects on bone strength. PMID:27983628
Chin, Kok-Yong; Gengatharan, Dhivakaran; Mohd Nasru, Fadlin Sakina; Khairussam, Rehan Amalia; Ern, Sherlyn Lai Hui; Aminuddin, Siti Aina Wahidah; Ima-Nirwana, Soelaiman
2016-12-14
Osteoporosis reduces the skeletal strength and increases the risk for fracture. It is an underdiagnosed disease in men. Annatto tocotrienol has been shown to improve bone structural indices and increase expression of bone formation genes in orchidectomized rats. This study aimed to evaluate the effects of annatto tocotrienol on biomechanical strength and calcium content of the bone in orchidectomized rats. Thirty three-month-old male Sprague-Dawley rats were randomly assigned to five groups. The baseline control (BC) group was sacrificed at the onset of the study. The sham-operated group (SHAM) received olive oil (the vehicle of tocotrienol) orally daily and peanut oil (the vehicle of testosterone) intramuscularly weekly. The remaining rats were orchidectomized and treated with three different regimens, i.e., (1) daily oral olive oil plus weekly intramuscular peanut oil injection; (2) daily oral annatto tocotrienol at 60 mg/kg plus weekly intramuscular peanut oil injection; (3) daily oral olive oil plus weekly intramuscular testosterone enanthate injection at 7 mg/kg. Blood, femur and tibia of the rats were harvested at the end of the two-month treatment period for the evaluation of serum total calcium and inorganic phosphate levels, bone biomechanical strength test and bone calcium content. Annatto-tocotrienol treatment improved serum calcium level and tibial calcium content ( p < 0.05) but it did not affect femoral biomechanical strength ( p > 0.05). In conclusion, annatto-tocotrienol at 60 mg/kg augments bone calcium level by preventing calcium mobilization into the circulation. A longer treatment period is needed for annatto tocotrienol to exert its effects on bone strength.
Emmelot-Vonk, M H; Verhaar, H J J; Nakhai-Pour, H R; Grobbee, D E; van der Schouw, Y T
2009-01-01
Serum testosterone levels decline significantly with aging and this has been associated with reduced sexual function. We have conducted a double-blind, randomized, placebo-controlled trial to investigate the effect of testosterone supplementation on sexual function in 237 elderly men with a testosterone level <13.7 nmol l(-1). Participants were randomly assigned to receive oral testosterone undecanoate or a placebo for 6 months. A total of 207 men completed the study. After treatment, there were no differences in scores on sexual function between the groups. Subanalysis showed that although a baseline testosterone level in the lowest tertile was associated with significantly lower scores for sexual fantasies, desire of sexual contact and frequency of sexual contact, supplementation of testosterone did not result in improvement on any of these items in this group. In conclusion, the findings do not support the view that testosterone undecanoate supplementation for 6 months to elderly men with low-normal testosterone concentrations favorably affects sexual function.
Patterns of testosterone prescription overuse.
Jasuja, Guneet K; Bhasin, Shalender; Rose, Adam J
2017-06-01
There has been an increase in the prescribing of testosterone therapy in the past decade. There is concern that at least part of this increase is driven by advertising rather than sound medical practice. The purpose of this review is to summarize the recent trends in testosterone prescribing, and to examine whether testosterone is being appropriately prescribed as per guidelines. Both global and U.S. data reflect an overall increase in the use of testosterone in the last decade, although there are early signs of a decline in testosterone sales since 2014. This increased prescribing has been accompanied with an overall increase in testing for testosterone levels, prescription of testosterone without the appropriate diagnostic evaluation recommended by clinical practice guidelines, and apparent use of this therapy for unproven medical conditions. Research to date suggests that there is room to improve our prescribing of testosterone. Greater understanding of the potential provider-level and system-level factors that contribute to the current prescribing practices may help accomplish such improvement.
Prenatal and pubertal testosterone affect brain lateralization.
Beking, T; Geuze, R H; van Faassen, M; Kema, I P; Kreukels, B P C; Groothuis, T G G
2018-02-01
After decades of research, the influence of prenatal testosterone on brain lateralization is still elusive, whereas the influence of pubertal testosterone on functional brain lateralization has not been investigated, although there is increasing evidence that testosterone affects the brain in puberty. We performed a longitudinal study, investigating the relationship between prenatal testosterone concentrations in amniotic fluid, pubertal testosterone concentrations in saliva, and brain lateralization (measured with functional Transcranial Doppler ultrasonography (fTCD)) of the Mental Rotation, Chimeric Faces and Word Generation tasks. Thirty boys and 30 girls participated in this study at the age of 15 years. For boys, we found a significant interaction effect between prenatal and pubertal testosterone on lateralization of Mental Rotation and Chimeric Faces. In the boys with low prenatal testosterone levels, pubertal testosterone was positively related to the strength of lateralization in the right hemisphere, while in the boys with high prenatal testosterone levels, pubertal testosterone was negatively related to the strength of lateralization. For Word Generation, pubertal testosterone was negatively related to the strength of lateralization in the left hemisphere in boys. For girls, we did not find any significant effects, possibly because their pubertal testosterone levels were in many cases below quantification limit. To conclude, prenatal and pubertal testosterone affect lateralization in a task-specific way. Our findings cannot be explained by simple models of prenatal testosterone affecting brain lateralization in a similar way for all tasks. We discuss alternative models involving age dependent effects of testosterone, with a role for androgen receptor distribution and efficiency. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Wenisch, Judith M; Mayr, Florian B; Spiel, Alexander O; Radicioni, Milko; Jilma, Bernd; Jilma-Stohlawetz, Petra
2014-03-01
Prostate-specific antigen (PSA) is used as an outcome measure for relapsed disease in prostate cancer. Nonetheless, there are considerable concerns about its indiscriminate use as a surrogate endpoint for cell growth or survival. We hypothesized that treatment with a luteinizing hormone releasing hormone (LHRH) analog would decrease PSA levels even in the absence of malignant disease. We determined testosterone and PSA levels in 30 healthy volunteers after a single intramuscular injection of a LHRH depot formulation. Testosterone and PSA levels were quantified by radioimmunoassay and electrochemi-luminescence immunoassay, respectively. After an initial flare-up during the first 3 days testosterone decreased reaching castration levels in 18 of the 30 young men (60%). After the nadir on day 28, testosterone levels increased to normal again. Changes in PSA paralleled those of testosterone. Castration reduced PSA levels by 29% (95% CI 19%-39%) compared to baseline (p<0.0001). LHRH superagonists decrease PSA levels by testosterone deprivation. Conferring these findings to tumor patients, decreases in PSA after treatment with LHRH analogs might not only reflect disease regression but also a direct testosterone mediated effect on PSA. Thus, PSA levels should be cautiously interpreted when patients receive hormonal therapy.
Panizzon, Matthew S; Hauger, Richard L; Xian, Hong; Jacobson, Kristen; Lyons, Michael J; Franz, Carol E; Kremen, William S
2018-05-01
Animal and human research suggests that testosterone is associated with hippocampal structure and function. Studies examining the association between testosterone and either hippocampal structure or hippocampal-mediated cognitive processes have overwhelmingly focused on the effects of testosterone alone, without considering the interaction of other neuroendocrine factors. The aim of the present study was to examine the interactive effects of testosterone and cortisol in relation to hippocampal volume and episodic memory in a sample of late-middle aged men from the Vietnam Era Twin Study of Aging. The average age of participants was 56.3 years (range 51-60). Salivary hormone samples were collected at multiple time-points on two non-consecutive at-home days, and an in-lab assessment. Area under the curve with respect to ground measures for cortisol and testosterone were utilized. Significant testosterone-by-cortisol interactions were observed for hippocampal volume, and episodic memory. When cortisol levels were elevated (1 SD above the mean), testosterone levels were positively associated with hippocampal volume and memory performance. However, when cortisol levels were low (1 SD below the mean), testosterone levels were inversely related to hippocampal volume and memory performance. These findings suggest that in context of high cortisol levels, testosterone may be neuroprotective. In contrast, low testosterone may also be neuroprotective in the context of low cortisol levels. To our knowledge this is the first demonstration of such an interaction in a structural brain measure and an associated cognitive ability. These results argue in favor of broadening neuroendocrine research to consider the simultaneous and interactive effects of multiple hormones on brain structure and function. Copyright © 2018 Elsevier Ltd. All rights reserved.
Stanton, Steven J.; Beehner, Jacinta C.; Saini, Ekjyot K.; Kuhn, Cynthia M.; LaBar, Kevin S.
2009-01-01
Background Political elections are dominance competitions. When men win a dominance competition, their testosterone levels rise or remain stable to resist a circadian decline; and when they lose, their testosterone levels fall. However, it is unknown whether this pattern of testosterone change extends beyond interpersonal competitions to the vicarious experience of winning or losing in the context of political elections. Women's testosterone responses to dominance competition outcomes are understudied, and to date, a clear pattern of testosterone changes in response to winning and losing dominance competitions has not emerged. Methodology/Principal Findings The present study investigated voters' testosterone responses to the outcome of the 2008 United States Presidential election. 183 participants provided multiple saliva samples before and after the winner was announced on Election Night. The results show that male Barack Obama voters (winners) had stable post-outcome testosterone levels, whereas testosterone levels dropped in male John McCain and Robert Barr voters (losers). There were no significant effects in female voters. Conclusions/Significance The findings indicate that male voters exhibit biological responses to the realignment of a country's dominance hierarchy as if they participated in an interpersonal dominance contest. PMID:19844583
Ryan, Calen P; Georgiev, Alexander V; McDade, Thomas W; Gettler, Lee T; Eisenberg, Dan T A; Rzhetskaya, Margarita; Agustin, Sonny S; Hayes, M Geoffrey; Kuzawa, Christopher W
2017-06-01
The androgen receptor (AR) mediates expression of androgen-associated somatic traits such as muscle mass and strength. Within the human AR is a highly variable glutamine short-tandem repeat (AR-CAGn), and CAG repeat number has been inversely correlated to AR transcriptional activity in vitro. However, evidence for an attenuating effect of long AR-CAGn on androgen-associated somatic traits has been inconsistent in human populations. One possible explanation for this lack of consistency is that the effect of AR-CAGn on AR bioactivity in target tissues likely varies in relation to circulating androgen levels. We tested whether relationships between AR-CAGn and several androgen-associated somatic traits (waist circumference, lean mass, arm muscle area, and grip strength) were modified by salivary (waking and pre-bed) and circulating (total) testosterone (T) levels in young adult males living in metropolitan Cebu, Philippines (n = 675). When men's waking T was low, they had a reduction in three out of four androgen-associated somatic traits with lengthening AR-CAGn (p < .1), consistent with in vitro research. However, when waking T was high, we observed the opposite effect-lengthening AR-CAGn was associated with an increase in these same somatic traits. Our finding that longer AR-CAGn predicts greater androgen-associated trait expression among high-T men runs counter to in vitro work, but is generally consistent with the few prior studies to evaluate similar interactions in human populations. Collectively, these results raise questions about the applicability of findings derived from in vitro AR-CAGn studies to the receptor's role in maintaining androgen-associated somatic traits in human populations. © 2017 Wiley Periodicals, Inc.
Testosterone levels and cognition in elderly men: a review.
Holland, J; Bandelow, S; Hogervorst, E
2011-08-01
Average testosterone levels and many cognitive functions show a decline with age. There is evidence to suggest that this association is not just age related. Results from cell culture and animal studies provide convincing evidence that testosterone could have protective effects on brain function. Alzheimer's disease (AD) is characterised by brain pathology affecting cognitive function and AD prevalence increases with age. Testosterone levels are lower in AD cases compared to controls, and some studies have suggested that low free testosterone (FT) may precede AD onset. Men with AD may show accelerated endocrinological ageing, characterised by an earlier lowering of thyroid stimulating hormone, an earlier increase in sex hormone binding globulin (SHBG), a subsequent earlier decrease in FT and an earlier increase in gonadotropin levels in response to this. Positive associations have been found between testosterone levels and global cognition, memory, executive functions and spatial performance in observational studies. However, non-significant associations were also reported. It may be that an optimal level of testosterone exists at which some cognitive functions are improved. This may be modified with an older age, with a shifting of the optimal testosterone curve to maintain cognition to the left and a lower optimal level thus needed to be beneficial for the brain. Genetic factors, such as APOE and CAG polymorphisms may further interact with testosterone levels in their effects on cognition. The roles of SHBG, gonadotropins, thyroid hormones and estrogens in maintaining cognitive function and preventing dementia in men are also not completely understood and should be investigated further. Hypogonadal men do not seem to benefit from testosterone supplementation but small scale, short term intervention studies in eugonadal men with and without cognitive impairments have shown promising results. Larger randomised, controlled trials are needed to further investigate testosterone treatment in protecting against cognitive decline and/or dementia. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Wingfield, J C; Ramos-Fernandez, G; Nuñez-de la Mora, A; Drummond, H
1999-05-01
This study attempted to determine endocrine correlates of reproductive success in relation to major deleterious environmental conditions. In 1992, an El Niño southern oscillation event resulted in complete reproductive failure in a colony of blue-footed boobies, Sula nebouxi, on Isla Isabel in the Pacific Ocean off San Blas, Nayarit, Mexico (21.5 degrees N, 105.5 degrees W). In 1993, the El Niño event had waned and reproductive success was high. The mean sea surface temperature in 1992 was 26.69 degrees, the warmest year for 11 years of data (mean, 25.63 degrees ). In 1993, mean sea surface temperature was 25.75 degrees. Plasma levels of testosterone were highest during the egg-laying period in 1993 and declined markedly during incubation. There were no differences between males and females. Comparisons of testosterone levels between 1992 and 1993 (egg-laying time point removed for 1993) showed no significant differences. Thus reproductive failure during an El Niño year was not related to testosterone levels. Baseline plasma levels of corticosterone did not change over the nesting cycle in either sex. There was a trend for plasma levels of corticosterone to be higher in males and females during the earlier stages of breeding in 1992 compared with 1993, and if all levels were combined within years then females showed significantly higher plasma levels of corticosterone in the El Niño year. Plasma levels of corticosterone showed marked increases following capture and handling in both sexes and at every stage of the breeding cycle in each year. There was no variation in the adrenocortical responses to stress with year or stage of nesting in males. However, in females, maximum corticosterone levels were greatest during the parental phase of 1992, the El Niño year, when all nests ultimately failed. Comparisons of the dynamics of corticosterone changes during the capture stress protocol revealed no correlations with body mass in 1992 or 1993. These data suggest that although massive reproductive failure in the El Niño year was not related to testosterone levels, baseline circulating concentrations of corticosterone may have a role in inhibiting onset of breeding. In contrast, after the nesting cycle has been initiated, increased adrenocortical sensitivity to acute stress may be involved in nest abandonment. Copyright 1999 Academic Press.
Pallarés, María Eugenia; Adrover, Ezequiela; Baier, Carlos Javier; Bourguignon, Nadia S; Monteleone, Melisa C; Brocco, Marcela A; González-Calvar, Silvia I; Antonelli, Marta C
2013-07-01
Several studies have demonstrated that the presence of stressors during pregnancy induces adverse effects on the neuroendocrine system of the offspring later in life. In the present work, we investigated the effects of early programming on the male reproductive system, employing a prenatal stress (PS) paradigm. This study found that when pregnant dams were placed in a plastic restrainer three times a day during the last week of pregnancy, the offspring showed reduced anogenital distance and delayed testicular descent. Serum luteinising hormone (LH) and follicle-stimulating hormone (FSH) levels were decreased at postnatal day (PND) 28 and testosterone was decreased at PND 75. Increased testosterone plus dihydrotestosterone (T + DHT) concentrations correlated with increased testicular 5α Reductase-1 (5αR-1) mRNA expression at PND 28. Moreover, PS accelerated spermatogenesis at PND 35 and 60, and increased mean seminiferous tubule diameter in pubertal offspring and reduced Leydig cell number was observed at PND 35 and 60. PS offspring had increased androgen receptor (AR) mRNA level at PND 28, and at PND 35 had increased the numbers of Sertoli cells immunopositive for AR. Overall, the results confirm that stress during gestation can induce long-term effects on the male offspring reproductive system. Of particular interest is the pre-pubertal imbalance of circulating hormones that probably trigger accelerated testicular development, followed by an increase in total androgens and a decrease in testosterone concentration during adulthood. Exposure to an unfavourable intrauterine environment might prepare for harsh external conditions by triggering early puberty, increasing reproductive potential.
Zito, J Bayley; Hanna, Angy; Kadoo, Nora; Tomaszycki, Michelle L
2017-09-01
Early life stress has enduring effects on behavior and physiology. However, the effects on hormones and stress physiology remain poorly understood. In the present study, parents of zebra finches of both sexes were exposed to an increased foraging paradigm from 3 to 33days post hatching. Plasma and brains were collected from chicks at 3 developmental time points: post hatching days 25, 60 and adulthood. Plasma was assayed for testosterone (T), estradiol (E2), and corticosterone (CORT). The paraventricular nucleus of the hypothalamus was assessed for corticotrophin releasing factor (CRH) and glucocorticoid receptor (GR) expression. As expected, body mass was lower in nutritionally stressed animals compared to controls at multiple ages. Nutritionally stressed animals overall had higher levels of CORT than did control and this was particularly apparent in females at post hatching day 25. Nutritionally stressed animals also had a higher number of cells expressing CRH and GR in the paraventricular nucleus of the hypothalamus than did controls. There was an interaction, such that both measures were higher in control animals at PHD 25, but higher in NS animals by adulthood. Females, regardless of treatment, had higher circulating CORT and a higher number of cells expressing CRH than did males. Nutritionally stressed animals also had higher levels of T than did control animals, and this difference was greatest for males at post hatching day 60. There were no effects of nutritional stress on E2. These findings suggest that nutritional stress during development has long-lasting effects on testosterone and stress physiology. Copyright © 2017 Elsevier Inc. All rights reserved.
ESTROGEN LEVELS DO NOT RISE WITH TESTOSTERONE TREATMENT FOR TRANSGENDER MEN.
Chan, Kelly J; Jolly, Divya; Liang, Jennifer J; Weinand, Jamie D; Safer, Joshua D
2018-04-01
Existing transgender treatment guidelines suggest that for transmasculine treatment, there is a possible need for estrogen-lowering strategies adjunct to testosterone therapy. Further, guidelines advocate consideration of prophylactic female reproductive tissue surgeries for transgender men to avoid the possibility of estrogen-related health risks. Despite the paucity of objective data, some transgender men seek conversion inhibitors. We sought to determine estradiol levels in transgender men treated with testosterone therapy and the change in those levels with treatment, if any. Estradiol levels were extracted from the electronic medical records of 34 anonymized transgender men treated with testosterone therapy at the Endocrinology Clinic at Boston Medical Center. Data were sufficient to observe 6 years of follow-up. With increased testosterone levels in trans-gender men, a significant decrease in estradiol levels was noted. There was a significant negative correlation between testosterone levels and body mass index, which may serve to explain part of the mechanism for the fall in estradiol levels. Even though the fall in estradiol levels was significant statistically, the actual levels remained within the normal male range, even with 6 years of follow-up. These data suggest that when exogenous testosterone is used to achieve normal serum male testosterone levels for transgender men, it is converted to normal male levels of estradiol, with some decline in those estradiol levels that might be attributable to a fall in fat mass. There appears to be no role for aromatase conversion inhibitors or other estrogen-reducing strategies in trans-gender men. Abbreviation: BMI = body mass index.
Yolk testosterone reduces oxidative damages during postnatal development
Noguera, José Carlos; Alonso-Alvarez, Carlos; Kim, Sin-Yeon; Morales, Judith; Velando, Alberto
2011-01-01
Conditions experienced during early life can influence the development of an organism and several physiological traits, even in adulthood. An important factor is the level of oxidative stress experienced during early life. In birds, extra-genomic egg substances, such as the testosterone hormone, may exert a widespread influence over the offspring phenotype. Interestingly, testosterone can also upregulate the bioavailability of certain antioxidants but simultaneously increases the susceptibility to oxidative stress in adulthood. However, little is known about the effects of maternally derived yolk testosterone on oxidative stress in developing birds. Here, we investigated the role of yolk testosterone on oxidative stress of yellow-legged gull chicks during their early development by experimentally increasing yolk testosterone levels. Levels of antioxidants, reactive oxygen species and lipid oxidative damage were determined in plasma during nestlings' growth. Our results revealed that, contrary to control chicks, birds hatched from testosterone-treated eggs did not show an increase in the levels of oxidative damage during postnatal development. Moreover, the same birds showed a transient increase in plasma antioxidant levels. Our results suggest that yolk testosterone may shape the oxidative stress-resistance phenotype of the chicks during early development owing to an increase in antioxidant defences and repair processes. PMID:20659922
Testosterone and the metabolic syndrome.
Muraleedharan, Vakkat; Jones, T Hugh
2010-10-01
Metabolic syndrome and testosterone deficiency in men are closely Linked. Epidemiological studies have shown that Low testosterone Levels are associated with obesity, insulin resistance and an adverse Lipid profile in men. Conversely in men with metabolic syndrome and type 2 diabetes have a high prevalence of hypogonadism. Metabolic syndrome and Low testosterone status are both independently associated with increased all-cause and cardiovascular mortality. Observational and experimental data suggest that physiological replacement of testosterone produces improvement in insulin resistance, obesity, dyslipidae-mia and sexual dysfunction along with improved quality of Life. However, there are no Long-term interventional studies to assess the effect of testosterone replacement on mortality in men with Low testosterone Levels. This article reviews the observational and interventional clinical data in relation to testosterone and metabolic syndrome.
Matsuzaka, Hisashi; Maeshima, Hitoshi; Kida, Sayaka; Kurita, Hirofumi; Shimano, Takahisa; Nakano, Yoshiyuki; Baba, Hajime; Suzuki, Toshihito; Arai, Heii
2013-01-01
Testosterone may have a role distinct from cortisol in the pathophysiology of depression. The hypothalamus-pituitary-adrenal (HPA) axis affects the functions of sex steroid hormones through interaction with corticotropin-releasing hormone (CRH) and gonadotropin-releasing hormone (GnRH). The objective of this study was to investigate differences in serum levels of testosterone and cortisol in male and female patients with major depressive disorder (MDD). Participants included 87 inpatients with MDD at Juntendo University Koshigaya Hospital. Serum levels of testosterone and cortisol were assessed at admission. Matched controls included 128 healthy individuals. Data from MDD patients and controls were compared separately for men and women. Correlations between serum hormone levels and scores on the Hamilton Rating Scale for Depression (HAM-D) of patients were assessed by sex. Effects of various factors on testosterone and cortisol were analyzed using multiple regression analysis. In male patients with MDD, a significant negative correlation was seen between testosterone levels and the "retardation" score of HAM-D. However, serum testosterone levels were not significantly different in either male or female MDD patients compared with controls. Serum testosterone was negatively associated with the number of depressive episodes in male patients with MDD. Serum cortisol levels in female patients were significantly increased compared with female controls with no significant correlations between cortisol levels and HAM-D scores. The negative correlation between the sub-score of the HAM-D and testosterone may be associated with the biological pathophysiology of male depression. Findings of serum cortisol levels in women may suggest distinct characteristics of these hormones in men and women with MDD.
Hasegawa, Masaru; Arai, Emi; Sato, Megumi; Sakai, Hidetsugu
2017-08-01
Recent experimental studies involving the manipulation of sexual traits have demonstrated that sexual trait expression feeds back to testosterone levels, perhaps via social interactions, reinforcing the linkage between sexual trait expression and testosterone levels during the mating period. However, information on this reinforcement under the natural variation of sexual traits remains limited. Using Japanese barn swallows, Hirundo rustica gutturalis, in which extra-pair paternity is quite rare (< 3%), we studied the relationship between plasma testosterone level and a male sexual trait, throat patch size, during the mating and incubation periods. Given the importance of social interaction, we predicted that this relationship should be intense during the mating period, but not the incubation period, due to reduced social interaction during the latter. We found low plasma testosterone levels during the incubation period compared with those in the mating period, and plasma testosterone levels were significantly positively related to throat patch area during the mating period, but not the incubation period. Similar relationships were found in another sexual trait, the size of white tail spots. During the incubation period, body condition, instead of male sexual trait expression, was negatively related to plasma testosterone level, indicating that an intrinsic link, rather than reinforcement, is important during this period. These relationships are consistent with the hypothesis that social interaction reinforces the relationship between sexual traits and plasma testosterone levels. The current study provides evidence for a highly variable relationship between testosterone and ornamentation across breeding periods in the natural variation of sexual traits.
Tsuchiya, T; Horii, I
1995-01-01
Time-course variations in plasma testosterone levels after various periods of immobilization stress (10 min, 30 min, 2 h, 6 h) were examined in male Syrian hamsters. The immobilization stress consisted of placing the animals in a prone position and wrapping them with flexible steel wire gauze. This was done at room temperature. Testosterone levels were determined in blood samples taken after the hamsters were decapitated. Chronic (2 h, 6 h) immobilization stress produced a drastic and enduring fall in plasma testosterone levels. Reduction of plasma testosterone following the 6-h immobilization stress was observed even 18 h after the stress had been relieved. However, acute (10 min, 30 min) immobilization stress did not influence plasma testosterone. These findings indicated that the effect of immobilization stress on plasma testosterone in hamsters was not biphasic, which it is in rats. Further, these results suggest that immobilization stress in hamsters would be a valuable technique with which to investigate the effects of physiological ranges of testosterone on physiological and psychological functions.
Nahata, Leena; Yu, Richard N; Bhasin, Shalender; Cohen, Laurie E
2015-05-01
Male hypogonadism is a common disorder that is associated with low bone density, poor muscle mass, anemia, and sexual dysfunction. The Endocrine Society recently published a Clinical Practice Guideline for testosterone therapy in androgen-deficient men. Because treatment is frequently initiated in adolescence, the goal of this quality improvement initiative was to assess whether pediatric endocrinologists at a large tertiary care center follow these guidelines and to identify opportunities for improvement. We performed a retrospective chart review at Boston Children's Hospital. Inclusion criteria were as follows: current age ≥16 years, diagnosis of hypogonadism, and testosterone replacement therapy. Data were collected about current age, age at treatment initiation, diagnoses, pre- and on-treatment testosterone levels, route of testosterone administration and dose, bone density, hematocrit levels, and adherence with therapy. Fifty-nine patients were included. Fourteen (24%) were prescribed lower testosterone doses than those recommended in the Clinical Practice Guideline. Seven (12%) had no pre-treatment testosterone levels, and 10 (17%) had no on-treatment levels. In 49 patients with on-treatment testosterone levels, 36 had at least one value that was lower than the adult reference range. Ten (28%) of the 36 men with low testosterone levels had no dose adjustments. Thirty-seven (63%) of the 59 patients had no dual-energy X-ray absorptiometry scans, and 18 (31%) did not have hematocrit levels. Pediatric endocrinologists in this review did not consistently follow the Clinical Practice Guideline for testosterone therapy in hypogonadal adult males. Strategies that improve adherence to guidelines could help maximize the benefits of therapy and minimize treatment-associated risks.
Cardiovascular issues in hypogonadism and testosterone therapy.
Shabsigh, Ridwan; Katz, Mark; Yan, Grace; Makhsida, Nawras
2005-12-26
A systematic literature search was conducted to investigate the cardiovascular issues related to hypogonadism and testosterone therapy. Vascular cells contain sex steroid hormone receptors. Testosterone can exert effects on the vascular wall, either by itself or through aromatization as estrogen. Hypogonadism is associated with central obesity; insulin resistance; low levels of high-density lipoprotein (HDL); high cholesterol levels; and high levels of low-density lipoprotein (LDL), triglycerides, fibrinogen, and plasminogen activator-1. Some observational studies show a correlation between low testosterone and cardiovascular disease (CVD), and others show no correlation. Interventional studies do not reveal a direct long-term relation between testosterone therapy and CVD. Short-term data suggest cardiovascular benefits of testosterone. Testosterone therapy has beneficial and deleterious effects on cardiovascular risk factors. It improves insulin sensitivity, central obesity, and lowers total cholesterol and LDL. In some studies, testosterone therapy has an HDL-lowering effect, and in other studies this effect is insignificant. This should not be assumed to be atherogenic because it might be related to reverse cholesterol transport and effects on the HDL(3) subfraction. The cardiovascular effects of testosterone therapy may be neutral to beneficial. There is no contraindication for testosterone therapy in men with CVD and diagnosed hypogonadism with or without erectile dysfunction. Caution should be exercised regarding occasional increases in hematocrit levels, especially in patients with congestive heart failure. Conversely, evidence does not support testosterone therapy in aging men for the purpose of cardiovascular benefit, despite claims to this effect. Further research on the cardiovascular benefits and risks of testosterone is strongly recommended.
Serum testosterone ... In males, the testicles produce most of the testosterone in the body. Levels are most often checked to evaluate signs of abnormal testosterone such as: Early or late puberty (in boys) ...
Association of Testosterone Levels With Anemia in Older Men
Roy, Cindy N.; Snyder, Peter J.; Stephens-Shields, Alisa J.; Artz, Andrew S.; Bhasin, Shalender; Cohen, Harvey J.; Farrar, John T.; Gill, Thomas M.; Zeldow, Bret; Cella, David; Barrett-Connor, Elizabeth; Cauley, Jane A.; Crandall, Jill P.; Cunningham, Glenn R.; Ensrud, Kristine E.; Lewis, Cora E.; Matsumoto, Alvin M.; Molitch, Mark E.; Pahor, Marco; Swerdloff, Ronald S.; Cifelli, Denise; Hou, Xiaoling; Resnick, Susan M.; Walston, Jeremy D.; Anton, Stephen; Basaria, Shehzad; Diem, Susan J.; Wang, Christina; Schrier, Stanley L.; Ellenberg, Susan S.
2017-01-01
Importance In one-third of older men with anemia, no recognized cause can be found. Objective To determine if testosterone treatment of men 65 years or older with unequivocally low testosterone levels and unexplained anemia would increase their hemoglobin concentration. Design, Setting, and Participants A double-blinded, placebo-controlled trial with treatment allocation by minimization using 788 men 65 years or older who have average testosterone levels of less than 275 ng/dL. Of 788 participants, 126 were anemic (hemoglobin Š12.7 g/dL), 62 of whom had no known cause. The trial was conducted in 12 academic medical centers in the United States from June 2010 to June 2014. Interventions Testosterone gel, the dose adjusted to maintain the testosterone levels normal for young men, or placebo gel for 12 months. Main Outcomes and Measures The percent of men with unexplained anemia whose hemoglobin levels increased by 1.0 g/dL or more in response to testosterone compared with placebo. The statistical analysis was intent-to-treat by a logistic mixed effects model adjusted for balancing factors. Results The men had a mean age of 74.8 years and body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) of 30.7; 84.9% were white. Testosterone treatment resulted in a greater percentage of men with unexplained anemia whose month 12 hemoglobin levels had increased by 1.0 g/dL or more over baseline (54%) than did placebo (15%) (adjusted OR, 31.5; 95% CI, 3.7-277.8; P = .002) and a greater percentage of men who at month 12 were no longer anemic (58.3%) compared with placebo (22.2%) (adjusted OR, 17.0; 95% CI, 2.8-104.0; P = .002). Testosterone treatment also resulted in a greater percentage of men with anemia of known cause whose month 12 hemoglobin levels had increased by 1.0 g/dL or more (52%) than did placebo (19%) (adjusted OR, 8.2; 95% CI, 2.1-31.9; P = .003). Testosterone treatment resulted in a hemoglobin concentration of more than 17.5 g/dL in 6 men who had not been anemic at baseline. Conclusions and Relevance Among older men with low testosterone levels, testosterone treatment significantly increased the hemoglobin levels of those with unexplained anemia as well as those with anemia from known causes. These increases may be of clinical value, as suggested by the magnitude of the changes and the correction of anemia in most men, but the overall health benefits remain to be established. Measurement of testosterone levels might be considered in men 65 years or older who have unexplained anemia and symptoms of low testosterone levels. PMID:28241237
Hirokawa, Kumi; Taniguchi, Toshiyo; Fujii, Yasuhito; Takaki, Jiro; Tsutsumi, Akizumi
2016-08-01
The purpose of this longitudinal study was to ascertain if changes in job demands modify associations between changes in testosterone levels and andropause symptoms in male Japanese workers. A baseline survey including job demands and the Aging Males' Symptoms scale, lifestyle factors, and blood levels of testosterone was conducted in 2007. Among 192 men (mean age ± SD 52.2 ± 7.6 years) who completed all relevant questionnaires and provided blood at baseline, 104 men (50.9 ± 7.2 years) were followed up in 2009. Changes of variables in 2 years were calculated (data of follow-up minus those of baseline). Testosterone levels were increased significantly, whereas job demands and somatic symptoms were reduced significantly, at follow-up. Changes in testosterone levels were negatively associated with changes in total andropause symptoms, psychological symptoms, and sexual symptoms (standardized β = -0.27, -0.24, and, -0.29, p < 0.05, respectively), after adjustment for confounders. Changes in job demands were positively associated with changes in somatic symptoms (standardized β = 0.21, p < 0.05). Significant interactions of changes in testosterone levels and job demands were noted for changes in psychological symptoms (standardized β = 0.26, p < 0.05). For men with a 1-SD reduction in job demands, negative associations between changes in testosterone levels and psychological symptoms were intensified, but not for men with a 1-SD increase in job demands. Andropause symptoms may be affected by changes in testosterone levels and job demands. Change in job demands may modify associations between changes in testosterone levels and andropause symptoms.
Behringer, V; Deschner, T; Deimel, C; Stevens, J M G; Hohmann, G
2014-08-01
Research on age-related changes in morphology, social behavior, and cognition suggests that the development of bonobos (Pan paniscus) is delayed in comparison to chimpanzees (Pan troglodytes). However, there is also evidence for earlier reproductive maturation in bonobos. Since developmental changes such as reproductive maturation are induced by a number of endocrine processes, changes in hormone levels are indicators of different developmental stages. Age-related changes in testosterone excretion are an indirect marker for the onset of puberty in human and non-human primates. In this study we investigated patterns of urinary testosterone levels in male and female bonobos and chimpanzees to determine the onset of puberty. In contrast to other studies, we found that both species experience age-related changes in urinary testosterone levels. Older individuals of both sexes had significantly higher urinary testosterone levels than younger individuals, indicating that bonobos and chimpanzees experience juvenile pause. The males of both species showed a similar pattern of age-related changes in urinary testosterone levels, with a sharp increase in levels around the age of eight years. This suggests that species-differences in aggression and male mate competition evolved independently of developmental changes in testosterone levels. Females showed a similar pattern of age-related urinary testosterone increase. However, in female bonobos the onset was about three years earlier than in female chimpanzees. The earlier rise of urinary testosterone levels in female bonobos is in line with reports of their younger age of dispersal, and suggests that female bonobos experience puberty at a younger age than female chimpanzees. Copyright © 2014 Elsevier Inc. All rights reserved.
Neonatal testosterone partially organizes sex differences in stress-induced emotionality in mice.
Seney, Marianne L; Walsh, Christopher; Stolakis, Ryan; Sibille, Etienne
2012-05-01
Major depressive disorder (MDD) is a debilitating disorder of altered mood regulation. Despite well established sex differences in MDD prevalence, the mechanism underlying the increased female vulnerability remains unknown. Although evidence suggests an influence of adult circulating hormone levels on mood (i.e. activational effects of hormones), MDD prevalence is consistently higher in women across life stages (and therefore hormonal states), suggesting that additional underlying structural or biological differences place women at higher risk. Studies in human subjects and in rodent models suggest a developmental origin for mood disorders, and interestingly, a developmental process also establishes sex differences in the brain. Hence, based on these parallel developmental trajectories, we hypothesized that a proportion of the female higher vulnerability to MDD may originate from the differential organization of mood regulatory neural networks early in life (i.e. organizational effects of hormones). To test this hypothesis in a rodent system, we took advantage of a well-established technique used in the field of sexual differentiation (neonatal injection with testosterone) to masculinize sexually dimorphic brain regions in female mice. We then investigated adult behavioral consequences relating to emotionality by comparing neonatal testosterone-treated females to normal males and females. Under baseline/trait conditions, neonatal testosterone treatment of female mice did not influence adult emotionality, but masculinized adult locomotor activity, as revealed by the activational actions of hormones. Conversely, the increased vulnerability of female mice to develop high emotionality following unpredictable chronic mild stress (UCMS) was partially masculinized by neonatal testosterone exposure, with no effect on post-UCMS locomotion. The elevated female UCMS-induced vulnerability did not differ between adult hormone treated groups. These results demonstrate that sex differences in adult emotionality in mice are partially caused by the organizational effects of sex hormones during development, hence supporting a developmental hypothesis of the human adult female prevalence of MDD. Copyright © 2012 Elsevier Inc. All rights reserved.
Neonatal testosterone partially organizes sex differences in stress-induced emotionality in mice
Seney, Marianne L.; Walsh, Christopher; Stolakis, Ryan; Sibille, Etienne
2012-01-01
Major depressive disorder (MDD) is a debilitating disorder of altered mood regulation. Despite well established sex differences in MDD prevalence, the mechanism underlying the increased female vulnerability remains unknown. Although evidence suggests an influence of adult circulating hormone levels on mood (i.e. activational effects of hormones), MDD prevalence is consistently higher in women across life stages (and therefore hormonal states), suggesting that additional underlying structural or biological differences place women at higher risk. Studies in human subjects and in rodent models suggest a developmental origin for mood disorders, and interestingly, a developmental process also establishes sex differences in the brain. Hence, based on these parallel developmental trajectories, we hypothesized that a proportion of the female higher vulnerability to MDD may originate from the differential organization of mood regulatory neural networks early in life (i.e. organizational effects of hormones). To test this hypothesis in a rodent system, we took advantage of a well-established technique used in the field of sexual differentiation (neonatal injection with testosterone) to masculinize sexually dimorphic brain regions in female mice. We then investigated adult behavioral consequences relating to emotionality by comparing neonatal testosterone-treated females to normal males and females. Under baseline/trait conditions, neonatal testosterone treatment of female mice did not influence adult emotionality, but masculinized adult locomotor activity, as revealed by the activational actions of hormones. Conversely, the increased vulnerability of female mice to develop high emotionality following unpredictable chronic mild stress (UCMS) was partially masculinized by neonatal testosterone exposure, with no effect on post-UCMS locomotion. The elevated female UCMS-induced vulnerability did not differ between adult hormone treated groups. These results demonstrate that sex differences in adult emotionality in mice are partially caused by the organizational effects of sex hormones during development, hence supporting a developmental hypothesis of the human adult female prevalence of MDD. PMID:22394611
Grant, Eric J; Cologne, John B; Sharp, Gerald B; Eguchi, Hidetaka; Stevens, Richard G; Izumi, Shizue; Kim, Young-Min; Berrington de González, Amy; Ohishi, Waka; Nakachi, Kei
2018-02-01
Ionizing radiation and high levels of circulating estradiol are known breast cancer carcinogens. We investigated the risk of first primary postmenopausal breast cancer in relation to the combined effects of whole-body ionizing radiation exposure and prediagnostic levels of postmenopausal sex hormones, particularly bioavailable estradiol (bE 2 ). A nested case-control study of 57 incident breast cancer cases matched with 110 controls among atomic bomb survivors. Joint effects of breast radiation dose and circulating levels of sex hormones were assessed using binary regression and path analysis. Radiation exposure, higher levels of bE 2 , testosterone and progesterone, and established reproductive risk factors were positively associated with postmenopausal breast cancer risk. A test for mediation of the effect of radiation via bE 2 level suggested a small (14%) but significant mediation (p = 0.004). The estimated interaction between radiation and bE 2 was large but not significant (interaction = 3.86; p = 0.32). There is accumulating evidence that ionizing radiation not only damages DNA but also alters other organ systems. While caution is needed, some portion of the radiation risk of postmenopausal breast cancer appeared to be mediated through bE 2 levels, which may be evidence for cancer risks due to both direct and indirect effects of radiation.
Dhindsa, Sandeep; Ghanim, Husam; Batra, Manav; Kuhadiya, Nitesh D.; Abuaysheh, Sanaa; Sandhu, Sartaj; Green, Kelly; Makdissi, Antoine; Hejna, Jeanne; Chaudhuri, Ajay; Punyanitya, Mark
2016-01-01
OBJECTIVE One-third of men with type 2 diabetes have hypogonadotropic hypogonadism (HH). We conducted a randomized placebo-controlled trial to evaluate the effect of testosterone replacement on insulin resistance in men with type 2 diabetes and HH. RESEARCH DESIGN AND METHODS A total of 94 men with type 2 diabetes were recruited into the study; 50 men were eugonadal, while 44 men had HH. Insulin sensitivity was calculated from the glucose infusion rate (GIR) during hyperinsulinemic-euglycemic clamp. Lean body mass and fat mass were measured by DEXA and MRI. Subcutaneous fat samples were taken to assess insulin signaling genes. Men with HH were randomized to receive intramuscular testosterone (250 mg) or placebo (1 mL saline) every 2 weeks for 24 weeks. RESULTS Men with HH had higher subcutaneous and visceral fat mass than eugonadal men. GIR was 36% lower in men with HH. GIR increased by 32% after 24 weeks of testosterone therapy but did not change after placebo (P = 0.03 for comparison). There was a decrease in subcutaneous fat mass (−3.3 kg) and increase in lean mass (3.4 kg) after testosterone treatment (P < 0.01) compared with placebo. Visceral and hepatic fat did not change. The expression of insulin signaling genes (IR-β, IRS-1, AKT-2, and GLUT4) in adipose tissue was significantly lower in men with HH and was upregulated after testosterone treatment. Testosterone treatment also caused a significant fall in circulating concentrations of free fatty acids, C-reactive protein, interleukin-1β, tumor necrosis factor-α, and leptin (P < 0.05 for all). CONCLUSIONS Testosterone treatment in men with type 2 diabetes and HH increases insulin sensitivity, increases lean mass, and decreases subcutaneous fat. PMID:26622051
Association of testosterone levels and future suicide attempts in females with bipolar disorder
Sher, Leo; Grunebaum, Michael F.; Sullivan, Gregory M.; Burke, Ainsley K.; Cooper, Thomas B.; Mann, J. John; Oquendo, Maria A.
2015-01-01
Background Considerable evidence suggests that testosterone may play a role in the pathophysiology of mood disorders in females. This is the first prospective study to examine whether blood testosterone levels predict suicide attempts in females with bipolar disorder. Methods Females with a DSM-IV diagnosis of a bipolar disorder in a depressive or mixed episode with at least one past suicide attempt were enrolled. Demographic and clinical parameters were assessed and recorded. Plasma testosterone was assayed using a double antibody radioimmunoassay procedure. Patients were followed up prospectively for up to 2.5 years. Results At baseline, testosterone levels positively correlated with the number of previous major depressive episodes and suicide attempts. Cox proportional hazards regression analysis found that higher baseline testosterone levels predicted suicide attempts during the follow-up period. Limitations A limitation of the study is that the sample size is modest. Another limitation is that we did not have a bipolar nonattempter or healthy volunteer control group for comparison. Conclusion Testosterone levels may predict suicidal behavior in women with bipolar disorder. PMID:25012416
Developmental changes in serum androgen levels of Eastern Screech-Owls (Megascops asio)
Kozlowski, Corinne P.; Hahn, D. Caldwell
2010-01-01
We studied androgen production during development in nestling Eastern Screech-Owls (Megascops asio) and hypothesized that gender and hatch order might influence serum levels of testosterone and androstenedione. Testosterone levels were highest immediately after hatching and declined significantly in the 4 weeks leading to fledging. The average level of testosterone for 1-7 day-old owls was 3.99 - 0.68 ng/ml. At 22-28 days of age, the average testosterone level for nestling owls was 0.83 - 0.18 ng/ml. Testosterone levels did not differ between males or females. The average testosterone level for male nestlings was 2.23 - 0.29 ng/ml and 2.39 - 0.56 ng/ml for female nestlings. The average level of androstenedione for nestling owls was 1.92 - 0.11 ng/ml and levels remained constant throughout development. Levels were significantly higher in males than females. The average androstenedione level was 1.77 - 0.16 ng/ml for male nestlings and 1.05 - 0.24 ng/ml for female nestlings. Hatching order did not affect levels of either androgen. Our results provide a foundation for future studies of androgen production by nestling owls.
Testosterone and the metabolic syndrome
Muraleedharan, Vakkat; Jones, T. Hugh
2010-01-01
Metabolic syndrome and testosterone deficiency in men are closely Linked. Epidemiological studies have shown that Low testosterone Levels are associated with obesity, insulin resistance and an adverse Lipid profile in men. Conversely in men with metabolic syndrome and type 2 diabetes have a high prevalence of hypogonadism. Metabolic syndrome and Low testosterone status are both independently associated with increased all-cause and cardiovascular mortality. Observational and experimental data suggest that physiological replacement of testosterone produces improvement in insulin resistance, obesity, dyslipidae-mia and sexual dysfunction along with improved quality of Life. However, there are no Long-term interventional studies to assess the effect of testosterone replacement on mortality in men with Low testosterone Levels. This article reviews the observational and interventional clinical data in relation to testosterone and metabolic syndrome. PMID:23148165
Cobo, Gabriela; Gallar, Paloma; Di Gioia, Cristina; García Lacalle, Concepción; Camacho, Rosa; Rodriguez, Isabel; Ortega, Olimpia; Mon, Carmen; Vigil, Ana; Lindholm, Bengt; Carrero, Juan Jesús
Testosterone deficiency (hypogonadism) is common among men undergoing haemodialysis, but its clinical implications are not well characterized. Testosterone is an anabolic hormone that induces erythrocytosis and muscle synthesis. We hypothesized that testosterone deficiency would be associated with low muscle mass, physical inactivity and higher dosages of erythropoietin-stimulating agents (ESA). Single-center cross-sectional study of 57 male haemodialysis patients. None of the patients was undergoing testosterone replacement therapy. Total testosterone was measured in serum. Body composition (by bioelectrical impedance analysis) and physical activity (by the use of pedometers) were assessed. Patients with testosterone levels below the normal range were considered hypogonadal. Mean testosterone level was 321±146ng/dL; 20 patients (35%) were hypogonadal. Hypogonadal patients were older and had lower mean arterial blood pressure, higher interleukin-6 levels, lower lean body mass and higher fat body mass. A negative association between testosterone and normalized ESA dose was found in uni- and multivariate regression analyses. Testosterone levels directly correlated with lean body mass regardless of confounders. Hypogonadal patients had lower physical activity than their counterparts [2753±1784 vs. 4291±3225steps/day (p=0.04)]. The relationship between testosterone and physical activity was independent of age, comorbidities and inflammatory markers, but dependent on the proportion of muscle mass. Hypogonadism is common in our male haemodialysis population and is associated with higher ESA doses, reduced muscle mass and lower physical activity. The link between low testosterone levels and physical inactivity may conceivably relate to reduced muscle mass due to inadequate muscle protein synthesis. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.
Recabarren, Monica; Carrasco, Albert; Sandoval, Daniel; Diaz, Felipe; Sir-Petermann, Teresa; Recabarren, Sergio E
2017-09-07
The administration of testosterone to pregnant sheep to resemble fetal programming of the polycystic ovary syndrome could alter other hormones/factors of maternal origin with known effects on fetal growth. Hence, we studied the weekly profile of insulin, progesterone and glucose during a treatment with testosterone propionate given biweekly from weeks 5 to 17 of pregnancy (term at 21 weeks) and checked the outcome of their fetuses at 17 weeks of gestation after C-section. Control dams were only exposed to the vehicle of the hormone. The testosterone administration did not cause any significant change in the maternal weekly profile of insulin, progesterone or glucose concentration, although the plasma levels of testosterone in the treated dams were inversely correlated to the levels of progesterone. Testosterone treatment also induced an inverse correlation between mean maternal insulin levels and fetal insulin levels; however, the fetal zoometric parameters, body weight, or insulin levels did not differ between exposed and not exposed fetuses. Therefore, treatment with testosterone during pregnancy does not cause significant impact on insulin levels in the mother, leading to less effect on the programming of fetal growth.
Hair and Salivary Testosterone, Hair Cortisol, and Externalizing Behaviors in Adolescents.
Grotzinger, Andrew D; Mann, Frank D; Patterson, Megan W; Tackett, Jennifer L; Tucker-Drob, Elliot M; Harden, K Paige
2018-05-01
Although testosterone is associated with aggression in the popular imagination, previous research on the links between testosterone and human aggression has been inconsistent. This inconsistency might be because testosterone's effects on aggression depend on other moderators. In a large adolescent sample ( N = 984, of whom 460 provided hair samples), we examined associations between aggression and salivary testosterone, hair testosterone, and hair cortisol. Callous-unemotional traits, parental monitoring, and peer environment were examined as potential moderators of hormone-behavior associations. Salivary testosterone was not associated with aggression. Hair testosterone significantly predicted increased aggression, particularly at low levels of hair cortisol (i.e., Testosterone × Cortisol interaction). This study is the first to examine the relationship between hair hormones and externalizing behaviors and adds to the growing literature that indicates that androgenic effects on human behavior are contingent on aspects of the broader endocrine environment-in particular, levels of cortisol.
Krysiak, Robert; Gilowski, Wojciech; Okopień, Bogusław
2016-02-01
By reducing LDL cholesterol levels, statins may decrease androgen production. This study was aimed at investigating whether testosterone treatment has an impact on cardiometabolic risk factors in statin-treated men with late-onset hypogonadism (LOH). The study included 31 men with LOH who had been treated for at least 6 months with atorvastatin (20-40mg daily). On the basis of patient preference, atorvastatin-treated patients were divided into two matched groups of patients: receiving intramuscular testosterone enanthate (100mg weekly, n=16) and not treated with this hormone (n=15). Plasma lipids, glucose homeostasis markers, as well as plasma levels of androgens, uric acid, high-sensitivity C-reactive protein (hsCRP), homocysteine, and fibrinogen were assessed before and after 4 months of therapy. Compared with the control age-, weight, and lipid-matched statin-naïve subjects with LOH (n=12), atorvastatin-treated patients were characterized by decreased levels of testosterone, hsCRP, and homocysteine. In patients not receiving testosterone therapy, plasma lipids, glucose homeostasis markers, as well as plasma levels of the investigated risk factors remained at the similar levels throughout the whole period of atorvastatin treatment. In atorvastatin-naïve patients, testosterone increased its plasma levels and decreased HDL cholesterol. Apart from an increase in testosterone levels, if administered to atorvastatin-treated subjects with LOH, testosterone reduced plasma levels of LDL cholesterol, uric acid, hsCRP, homocysteine, and fibrinogen, as well as improved insulin sensitivity. Our study may suggest the clinical benefits associated with combination therapy with a statin and testosterone in elderly men with LOH. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.
Degarelix: a gonadotropin-releasing hormone antagonist for the management of prostate cancer.
Steinberg, Michael
2009-01-01
Prostate cancer is the most commonly diagnosed cancer among men. Treatment can include surgery, radiation, chemotherapy, or hormonal manipulation. Gonadotropin-releasing hormone (GnRH) analogues are used to manage prostate cancer by desensitizing the stimulus to synthesize and release gonadotropins, such as luteinizing hormone (LH), which stimulate the synthesis and release of androgens, in turn stimulating the growth of prostate cancer cells. Although effective, these agents have limitations, such as a flare-up of cancer symptoms within the first 2 weeks of starting the drug. This article reviews the pharmacology, pharmacokinetic and pharmacodynamic characteristics, and clinical data available on the newly approved drug degarelix for use in treating prostate cancer. A search of the medical literature was performed in January 2009 with the databases MEDLINE and EMBASE (1950-present) and International Pharmaceutical Abstracts (1970-November 2008) using the terms degarelix and FE200486; follow-up searches using the same strategy were conducted in May 2009 and August 2009. Additional sources were identified by scanning available references and online journals and textbooks. GnRH antagonists, such as degarelix, offer clinicians another means to reduce the level of circulating androgens and limit this growth stimulus directed at malignant prostate tissue. Degarelix has been shown in animal studies to antagonize GnRH receptors in the pituitary gland, resulting in a significant reduction in circulating LH and a subsequent decrease in the synthesis of testosterone. Pharmacokinetic analysis suggests that upon subcutaneous administration, degarelix forms a gel depot, from which the drug then distributes to the rest of the body in a first-order manner. A Phase II study of the effect of degarelix in 187 men with prostate cancer found a loading dose of 240 mg to be not significantly better than 200 mg in reducing serum testosterone concentrations to < or =0.5 ng/mL within 3 days of dosing (200 mg, 88%; 240 mg, 92%). This difference in percentage of patients with testosterone suppression became statistically significant when measured again 1 month into the study (200 mg, 86%; 240 mg, 95%; P = 0.048). Evaluation of 80-, 120-, and 160-mg maintenance doses found all doses effective in maintaining suppression of testosterone, LH, and prostate-specific antigen (PSA); only minor differences were observed during the study period. In a Phase III study of 610 patients with prostate cancer, a loading dose of degarelix 240 mg SC followed by monthly maintenance doses of either 80 or 160 mg was compared with monthly doses of leuprolide 7.5 mg IM. Degarelix was found to be at least as effective as leuprolide in the ability to suppress serum testosterone to < or =0.5 ng/mL for up to 1 year (degarelix response rate, 80 mg, 97.2%; 95% CI, 93.5%-98.8%; degarelix 160 mg, 98.3%; 95% CI, 94.8%-99.4%; leuprolide response rate, 96.4%; 95% CI, 92.5%-98.2%). Other studies investigating various doses and schedules of degarelix have also been conducted. Adverse effects of degarelix in clinical trials were mild and relatively uncommon and included flushing reactions, injection-site pain, weight gain, and increases in serum transaminase levels. Degarelix offers another option for chemical castration to reduce the androgenic growth stimulus on prostate cancer cells. The manufacturer of degarelix recommends a loading dose of 240 mg SC followed by the first monthly maintenance dose of 80 mg 28 days later. Serum testosterone and PSA concentrations must be obtained to monitor the response during treatment with degarelix. Copyright 2009 Excerpta Medica Inc. All rights reserved.
First case report of testosterone assay-interference in a female taking maca (Lepidium meyenii).
Srikugan, L; Sankaralingam, A; McGowan, B
2011-03-25
A young female with prolonged intermenstrual bleeding was found to have raised total plasma testosterone of 25.8 nmol/l (NR<2.9 nmol/l) using the Roche Elecsys Testosterone I immunoassay without clinical features of virulisation. Few months ago investigations for lethargy and low libido had shown normal total testosterone of 0.8 nmol/l. Further history revealed that she was using maca extract to improve her lethargy and low libido. Maca is traditionally used for its aphrodisiac and fertility-enhancing properties. Maca use has not been shown to affect serum testosterone in mice and human studies. Immunoassay interference with maca was suspected. Testosterone immunoassays use monoclonal antibodies specifically directed against testosterone. They are prone to interference from androgenic compounds. Reanalysis of the original serum sample using Elecsys Testosterone II assay, a higher affinity assay, revealed a total testosterone level of 2.9 nmol/l. It is important to exclude assay interference when testosterone level is greater than 5 nmol/l without supportive clinical signs.
First case report of testosterone assay-interference in a female taking maca (Lepidium meyenii)
Srikugan, L; Sankaralingam, A; McGowan, B
2011-01-01
A young female with prolonged intermenstrual bleeding was found to have raised total plasma testosterone of 25.8 nmol/l (NR<2.9 nmol/l) using the Roche Elecsys Testosterone I immunoassay without clinical features of virulisation. Few months ago investigations for lethargy and low libido had shown normal total testosterone of 0.8 nmol/l. Further history revealed that she was using maca extract to improve her lethargy and low libido. Maca is traditionally used for its aphrodisiac and fertility-enhancing properties. Maca use has not been shown to affect serum testosterone in mice and human studies. Immunoassay interference with maca was suspected. Testosterone immunoassays use monoclonal antibodies specifically directed against testosterone. They are prone to interference from androgenic compounds. Reanalysis of the original serum sample using Elecsys Testosterone II assay, a higher affinity assay, revealed a total testosterone level of 2.9 nmol/l. It is important to exclude assay interference when testosterone level is greater than 5 nmol/l without supportive clinical signs. PMID:22700073
Testosterone and Proactive-Reactive Aggression in Youth: the Moderating Role of Harsh Discipline.
Chen, Frances R; Raine, Adrian; Granger, Douglas A
2018-01-20
This study tests a biosocial model of the link between testosterone and proactive-reactive aggression in youth at varying levels of harsh discipline. Given that proactive aggression is used to gain power and status and the importance of social learning in its formation, we hypothesized that testosterone would be associated with proactive aggression at higher levels of harsh discipline, and that this relationship would be more pronounced in boys than girls. Participants (n = 445; 50% male; M age = 11.92 years; 80% African-American) and their caregivers completed questionnaires including demographics, conflict tactics, and proactive-reactive aggression. Youth also provided a saliva sample for testosterone. Analyses revealed an interaction between testosterone and harsh discipline on proactive aggression in both boys and girls, and an interaction between testosterone and harsh discipline on reactive aggression in boys only. For those experiencing high levels of harsh discipline, testosterone was positively associated with proactive aggression, with the magnitude of the association increasing as harsh discipline increased. For below average levels of harsh discipline, there were protective effects of high testosterone for boy's reactive aggression and for girl's proactive aggression. The findings support basic tenets of the biosocial model which suggest that links between testosterone and aggressive behavior are dependent on contextual forces, highlighting the complex relationship between hormones, social context, and aggression. Novel findings include protective effects of high testosterone for those exposed to low levels of harsh discipline. Findings are discussed in light of the context-contingency effect and also within the differential susceptibility framework.
Liu, Hui; Héroux, Paul; Zhang, Qunwei; Jiang, Zhao-Yan; Gu, Aihua
2015-01-01
Background Little is known regarding the effects of environmental exposure of chemicals on androgenic system in the general population. We studied 5,107 subjects included in the National Health and Nutrition Examination Survey (2011–2012). Methods Urinary, serum, and blood levels of 15 subclasses comprising 110 individual chemicals were analyzed for their association with serum testosterone levels. The subjects were divided into high and low testosterone groups according to the median testosterone concentration (374.51 ng/dL). Odds ratios (ORs) of individual chemicals in association with testosterone were estimated using logistic regression after adjusting for age, ethnicity, cotinine, body mass index, creatinine, alcohol, and the poverty income ratio. Results Adjusted ORs for the highest versus lowest quartiles of exposure were 2.12 (95% CI: 1.07, 4.21; Ptrend = 0.044), 1.84 (95% CI: 1.02, 3.34; Ptrend = 0.018) for the association between urinary mandelic acid, and strontium quartiles with low testosterone concentrations in adult men, respectively. However, no association was observed for the remaining chemicals with testosterone. Conclusions The National Health and Nutrition Examination Survey data suggest that elevations in urinary mandelic acid, and strontium levels are negatively related to low serum testosterone levels in adult men. PMID:25996772
Pedersen, L; Christensen, L L; Pedersen, S M; Andersen, M
2017-05-01
To investigate the effect of testosterone treatment on biomarkers calprotectin, fibroblast growth factor 23 (FGF23), soluble Klotho, phosphate, calcium, parathyroid hormone, creatinine and estimated glomerular filtration rate. Randomized, double-blinded, placebo-controlled study. Odense Androgen Study-the effect of Testim and training in hypogonadal men. Men aged 60-78 years old with a low normal concentration of free of bioavailable testosterone <7.3 nmol/L and waist circumference >94 cm recruited from 2008 to 2009 (N = 48) by advertisement. Participants were randomized to receive 5-10 g gel/50-100 mg testosterone (Testim ® , Ipsen, France) or 5-10 g gel/placebo. The plasma levels of calprotectin and phosphate were significantly reduced in the group receiving testosterone therapy (gel) compared to the placebo group (p < 0.05). Testosterone treatment did not have any significant effect on plasma levels of FGF23 or soluble Klotho. The reduction in phosphate levels was inversely associated with bioavailable testosterone. Compared to the placebo group, 6 months of testosterone therapy (gel) reduced calprotectin and phosphate levels suggesting decreased inflammation and decreased cardiovascular risk.
Women's Preference for Attractive Makeup Tracks Changes in Their Salivary Testosterone.
Fisher, Claire I; Hahn, Amanda C; DeBruine, Lisa M; Jones, Benedict C
2015-12-01
Previous research suggests that women's motivation to appear attractive is increased around the time of ovulation. However, the specific hormonal correlates of within-woman changes in motivation to appear attractive have not been investigated. To address this issue, we used a longitudinal design and a data-driven visual preference task. We found that women's preference for attractive makeup increases when their salivary testosterone levels are high. The relationship between testosterone level and preference for attractive makeup was independent of estradiol level, progesterone level, and estradiol-to-progesterone ratio. These results suggest that testosterone may contribute to changes in women's motivation to wear attractive makeup and, potentially, their motivation to appear attractive in general. Our results are also consistent with recent models of the role of testosterone in social behavior, according to which testosterone increases the probability of behaviors that could function to support the acquisition of mates and competition for resources. © The Author(s) 2015.
Hormonal Treatment of Transgender Women with Oral Estradiol.
Leinung, Matthew C; Feustel, Paul J; Joseph, Jalaja
2018-01-01
Purpose: Maintaining cross-sex hormone levels in the normal physiologic range for the desired gender is the cornerstone of transgender hormonal therapy, but there are limited data on how to achieve this. We investigated the effectiveness of oral estradiol therapy in achieving this goal. Methods: We analyzed data on all transgender females seen in our clinic since 2008 treated with oral estradiol. We looked at the success of achieving serum levels of testosterone and 17-β estradiol in the normal range on various doses of estradiol (with and without antiandrogens spironolactone and finasteride). Results: There was a positive correlation between estradiol dose and 17-β estradiol, but testosterone suppression was less well correlated. Over 70% achieved treatment goals (adequate 17-β estradiol levels and testosterone suppression) on 4 mg daily or more. Nearly a third of patients did not achieve adequate treatment goals on 6 or even 8 mg daily of estradiol. Spironolactone, but not finasteride, use was associated with impairment of obtaining desired 17-β estradiol levels. Spironolactone did not enhance testosterone suppression, and finasteride was associated with higher testosterone levels. Conclusions: Oral estradiol was effective in achieving desired serum levels of 17-β estradiol, but there was wide individual variability in the amount required. Oral estradiol alone was not infrequently unable to achieve adequate testosterone suppression. Spironolactone did not aid testosterone suppression and seemed to impair achievement of goal serum 17-β estradiol levels. Testosterone levels were higher with finasteride use. We recommend that transgender women receiving estradiol therapy have hormone levels monitored so that therapy can be individualized.
Relations between Prenatal Testosterone Levels and Cognitive Abilities at 4 Years.
ERIC Educational Resources Information Center
Finegan, Jo-Anne K.; And Others
1992-01-01
Compared children's cognitive abilities at four years and their prenatal amniotic fluid testosterone levels. For girls, prenatal testosterone levels were related in a curvilinear manner to language comprehension and classification abilities, and inversely related to counting and knowledge of number facts. For boys, no relationships were found. (BC)
Influence of Altered Mass Loading on Testosterone Levels and Testicular Mass
NASA Technical Reports Server (NTRS)
Wang, Tommy J.; Ortiz, R. M.; Wade, C. E.; Hargens, Alan R. (Technical Monitor)
1996-01-01
Effects of altered load on testosterone levels and testicular mass in mammals are not well defined. Two separate studies (loading;centrifuged; +2G(sub z) and unloading;hindlimb suspension;HLS) were conducted to provide a better understanding of the effects of mass loading on testosterone levels and testicular mass. Daily urine samples were collected, and testicular mass measured at the end of the study. +2G(sub z): Sprague-Dawley rats (230-250 g) were centrifuged for 12 days at +2G(sub z): 8 centrifuged (EC) and 8 off centrifuge controls (OCC). EC had lower body mass, however relative testicular mass was greater. EC exhibited an increase in excreted testosterone levels between days 2 (T2) and 6 (T6), and returned to baseline at T9. HLS: To assess the effects of unloading Sprague-Dawley rats (125-150 g) were studied for 12 days: 10 suspended (Exp) and 10 ambulatory (Ctl). Exp had lower body mass during the study, with reduced absolute and relative testicular mass. Exp demonstrated lower excreted testosterone levels from T5-T12. Conclusions: Loading appears to stimulate anabolism, as opposed to unloading, as indicated by greater relative testicular mass and excreted testosterone levels. Reported changes in muscle mass during loading and unloading coincide with similar changes in excreted testosterone levels.
Swelum, Ayman Abdel-Aziz; Saadeldin, Islam M; Zaher, Hany A; Alsharifi, Sawsan A M; Alowaimer, Abdullah N
2017-06-01
We studied the effect of sexual excitation on serum testosterone and nitric oxide (NO) levels in water buffalo bulls with different categories of sexual behavior and their correlation with each other. Buffalo bulls were classified according to their sexual behavior (including reaction time, sexual aggressiveness and mating ability): acceptable (good to excellent) (n=5), fair (n=5), and unacceptable (poor) (n=5) sexual behavior. Blood samples were collected from all animals immediately before and after sexual teasing and/or mounting to estimate the testosterone and NO levels using a commercial radioimmunoassay kit and Griess reaction test, respectively. Comparisons among groups were evaluated using a mixed-design analysis of variance. Pearson's correlation coefficients were calculated to determine the relationship between testosterone and NO levels before and after sexual excitation besides sexual behavior. The level of testosterone before sexual excitation was higher (p≤0.05) in bulls with acceptable and fair sexual behavior than in bulls with unacceptable sexual behavior (0.86±0.01, 0.69±0.02, and 0.29±0.02ng/mL, respectively). The level of NO was higher (p≤0.05) in bulls with acceptable and fair sexual behavior than in bulls with unacceptable sexual behavior (8.00±0.03, 7.66±0.19, and 6.29±0.33μM, respectively). Sexual excitation significantly (p<0.05) increase testosterone and NO levels in bulls with acceptable (1.45±0.01ng/mL and 19.04±0.32μM, respectively) or fair (0.92±0.02ng/mL and 14.95±0.34μM, respectively) sexual behavior, but not in bulls with unacceptable sexual behavior. The unacceptable sexual behavior bulls had significantly lower testosterone and NO levels than the other bulls. There was a strong correlation and association between serum testosterone and NO levels besides sexual behavior of buffalo bulls. In conclusion, the alteration in the testosterone and NO levels after sexual excitation depends on the sexual behavior category of buffalo-bull. Testosterone and NO can be used to create a sexual behavior score. The testosterone and NO levels of can be predicted via evaluation of sexual behavior of buffalo bull. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.
Purpose: Low testosterone has been implicated as a possible adverse prognostic factor in patients with newly diagnosed prostate cancer. We evaluated the impact of pretreatment serum testosterone on survival after prostate brachytherapy. Methods and Materials: From October 2001 to November 2004, 619 patients underwent brachytherapy and 546 had a pretreatment serum testosterone level measured. Pretreatment serum testosterone levels were assigned by the following criteria: below-normal (n = 105), low normal (n = 246), mid normal (n = 132), high normal (n = 50), and above normal (n = 13). Median follow-up was 5.2 years. Cause of death was determined formore » each deceased patient. Results: Six-year biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were 97.7%, 99.8%, and 89.2%. When comparing patients with low or low normal testosterone with those with average or higher testosterone, there was no significant difference in bPFS (97.6% vs. 98.4%; p = 0.72), CSS (99.8% vs. 100%; p = 0.72), or OS (88.9% vs. 90.8%; p = 0.73). Among patients with average and higher pretreatment testosterone, there was no significant difference in outcomes when comparing patients who did and did not receive androgen deprivation therapy (ADT). For patients with low or low normal testosterone levels, there was no significant difference in bPFS or CSS when comparing patients who did and did not receive ADT. However, there was a trend toward lower OS in patients with baseline lower testosterone levels who also received ADT (83.9% vs. 91.3%, p = 0.075). Conclusions: Low pretreatment testosterone levels alone did not affect disease recurrence or OS. Patients with baseline low testosterone who also were treated with ADT had a trend toward decreased OS.« less
Dabaja, Ali A; Bryson, Campbell F; Schlegel, Peter N; Paduch, Darius A
2015-03-01
To evaluate the relationship of testosterone-enhancing therapy on alkaline phosphatase (AP) in relation to bone mineral density (BMD) in hypogonadal men. Retrospective review of 140 men with testosterone levels of <350 ng/dL undergoing testosterone-enhancing therapy and followed for 2 years. Follicle-stimulating hormone, luteinising hormone, free testosterone, total testosterone, sex hormone binding globulin, calcium, AP, vitamin D, parathyroid hormone, and dual-energy X-ray absorptiometry (DEXA) scans were analysed. A subgroup of 36 men with one DEXA scan before and one DEXA 2 years after initiating treatment was performed. Analysis of the relationship between testosterone and AP at initiation of therapy using stiff linear splines suggested that bone turnover occurs at total testosterone levels of <250 ng/dL. In men with testosterone levels of <250 ng/dL, there was a negative correlation between testosterone and AP (R(2) = -0.347, P < 0.001), and no correlation when testosterone levels were between 250 and 350 ng/dL. In the subgroup analysis, the mean (sd) testosterone level was 264 (103) ng/dL initially and 701 (245), 539 (292), and 338 (189) ng/dL at 6, 12, and 24 months, respectively. AP decreased from a mean (sd) of 87 (38) U/L to 57 (12) U/L (P = 0.015), 60 (17) U/L (P < 0.001), and 55 (10) U/L (P = 0.03) at 6, 12, and 24 months, respectively. The BMD increased by a mean (sd) of 20 (39)% (P = 0.003) on DEXA. In hypogonadal men, the decrease in AP is associated with an increase in BMD on DEXA testing. This result suggests the use of AP as a marker of response to therapy. © 2014 The Authors. BJU International © 2014 BJU International.
Iwasa, Takeshi; Matsuzaki, Toshiya; Yano, Kiyohito; Yanagihara, Rie; Tungalagsuvd, Altankhuu; Munkhzaya, Munkhsaikhan; Mayila, Yiliyasi; Kuwahara, Akira; Irahara, Minoru
2017-07-01
In females, estrogens play pivotal roles in preventing excess body weight (BW) gain. On the other hand, the roles of androgens in female BW, appetite, and energy metabolism have not been fully examined. We hypothesized that androgens' effects on food intake (FI) and BW regulation change according to the estrogens' levels. To evaluate this hypothesis, the effects of chronic testosterone administration in ovariectomized (OVX) female rats with or without estradiol supplementation were examined in this study. Chronic testosterone administration decreased BW, FI, white adipose tissue (WAT) weight, and adipocyte size in OVX rats, whereas it increased BW, WAT weight, and adipocyte size in OVX with estradiol-administered rats. In addition, chronic testosterone administration increased hypothalamic CYP19a1 mRNA levels in OVX rats, whereas it did not alter CYP19a1 mRNA levels in OVX with estradiol-administered rats, indicating that conversion of testosterone to estrogens in the hypothalamus may be activated in testosterone-administered OVX rats. Furthermore, chronic testosterone administration decreased hypothalamic TNF-α mRNA levels in OVX rats, whereas it increased hypothalamic IL-1β mRNA levels in OVX with estradiol-administered rats. On the other hand, IL-1β and TNF-α mRNA levels in visceral and subcutaneous WAT and liver were not changed by chronic testosterone administration in both groups. These data indicate that the effects of chronic testosterone administration on BW, FI, WAT weight, and adipocyte size were changed by estradiol treatment in female rats. Testosterone has facilitative effects on BW gain, FI, and adiposity under the estradiol-supplemented condition, whereas it has inhibitory effects in the non-supplemented condition. Differences in the responses of hypothalamic factors, such as aromatase and inflammatory cytokines, to testosterone might underlie these opposite effects. Copyright © 2017 Elsevier Inc. All rights reserved.
Barakat, Radwa; Lin, Po-Ching; Park, Chan Jin; Best-Popescu, Catherine; Bakery, Hatem H; Abosalum, Mohamed E; Abdelaleem, Nabila M; Flaws, Jodi A; Ko, CheMyong
2018-04-23
Phthalates are a family of synthetic chemicals that are used in producing a variety of consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is an widely used phthalate and poses a public health concern. Prenatal exposure to DEHP has been shown to induce premature reproductive senescence in animal studies. In this study, we tested the hypothesis that prenatal exposure to DEHP impairs neurobehavior and recognition memory in her male offspring and we investigated one possible mechanism-oxidative damage in the hippocampus. Pregnant CD-1 female mice were orally administered 200μg, 500mg, or 750mg/kg/day DEHP or vehicle from gestational day 11 until birth. The neurobehavioral impact of the prenatal DEHP exposure was assessed at the ages of 16 to 22 months. Elevated plus maze and open field tests were used to measure anxiety levels. Y-maze and novel object recognition tests were employed to measure memory function. The oxidative damage in the hippocampus was measured by the levels of oxidative DNA damage and by SLIM microscopic counting of hippocampal neurons. Adult male mice that were prenatally exposed to DEHP exhibited anxious behaviors and impaired spatial and short-term recognition memory. The number of hippocampal pyramidal neurons was significantly decreased in the DEHP mice. Furthermore, DEHP mice expressed remarkably high levels of cyclooxygenase-2, 8-hydroxyguanine, and thymidine glycol in their hippocampal neurons. DEHP mice also had lower circulating testosterone concentrations and displayed a weaker immunoreactivity than the control mice to androgen receptor expression in the brain. This study found that prenatal exposure to DEHP caused elevated anxiety behavior and impaired recognition memory. These behavioral changes may originate from neurodegeneration caused by oxidative damage and inflammation in the hippocampus. Decreased circulating testosterone concentrations and decreased expression of androgen receptor in the brain also may be factors contributing to the impaired neurobehavior in the DEHP mice.
The androgen-deficient aging male: current treatment options.
Tenover, J Lisa
2003-01-01
All delivery forms of testosterone should be equally efficacious in treating the androgen-deficient aging male if adequate serum testosterone levels are obtained. The testosterone preparations available in North America include the oral undecanoate, injectable testosterone esters, the scrotal patch, the nonscrotal transdermal patch, and the transdermal gels. Selection of a specific testosterone preparation for replacement therapy depends on many factors, including the magnitude and pattern of serum testosterone levels produced, side effects of the particular formulation, reversibility if an adverse event should occur, convenience of use, cosmetic issues related to the preparation, and cost. In addition, potential adverse effects of testosterone therapy applicable to all forms of testosterone delivery, such as fluid retention, gynecomastia, polycythemia, worsening of sleep apnea, change in cardiovascular-disease risk, or alterations in prostate health, need to be considered both prior to therapy and during treatment monitoring.
Han, Aijie; Zou, Lingyue; Gan, Xiaoqin; Li, Yu; Liu, Fangfang; Chang, Xuhong; Zhang, Xiaotian; Tian, Minmin; Li, Sheng; Su, Li; Sun, Yingbiao
2018-06-15
Nickel (Ni) can disorder testosterone synthesis in rat Leydig cells, whereas the mechanisms remain unclear. The aim of this study was to investigate the role of reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPKs) in Ni-induced disturbance of testosterone synthesis in rat Leydig cells. The testosterone production and ROS levels were detected in Leydig cells. The mRNA and protein levels of testosterone synthetase, including StAR, CYP11A1, 3β-HSD, CYP17A1 and 17β-HSD, were determined. Effects of Ni on the ERK1/2, p38 and JNK MAPKs were also investigated. The results showed that Ni triggered ROS generation, consequently resulted in the decrease of testosterone synthetase expression and testosterone production in Leydig cells, which were then attenuated by ROS scavengers of N-acetylcysteine (NAC) and 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), indicating that ROS are involved in the Ni-induced testosterone biosynthesis disturbance. Meanwhile Ni activated the ERK1/2, p38 and JNK MAPKs. Furthermore, Ni-inhibited testosterone synthetase expression levels and testosterone secretion were all alleviated by co-treatment with MAPK specific inhibitors (U0126 and SB203580, respectively), implying that Ni inhibited testosterone synthesis through activating ERK1/2 and p38 MAPK signal pathways in Leydig cells. In conclusion, these findings suggest that Ni causes testosterone synthesis disorder, partly, via ROS and MAPK signal pathways. Copyright © 2018 Elsevier B.V. All rights reserved.
Relating testosterone levels and free play social behavior in male and female preschool children.
Sánchez-Martín, J R; Fano, E; Ahedo, L; Cardas, J; Brain, P F; Azpíroz, A
2000-11-01
This study assessed potential relationships between a series of behavioral measures seen in the interactions of preschool children with their peers (particularly aggressive behavior) and testosterone levels. 28 boys and 20 girls of preschool age were videotaped in free play interactions. Their behavior was then evaluated with particular emphasis on aggression and affiliation in play and social interactions. Testosterone levels were measured using radioimmunoassay in saliva samples. Correlation analysis revealed a positive relationship in boys between testosterone and giving and receiving aggression in the context of 'social interactions' (serious aggression), but not in the context of play (playful aggresstion). Testosterone can be a useful biological marker for serious aggression (and behavioral patterns reflecting different levels of sociability) in preschool boys.
Androgen replacement for women.
Basson, R.
1999-01-01
OBJECTIVES: To determine whether a postmenopausal syndrome comprising specific changes in sexual desire and response associated with low free testosterone exists. To determine whether this syndrome is ameliorated by testosterone replacement. QUALITY OF EVIDENCE: Literature documenting that replacement of physiological levels of testosterone is beneficial and safe is scant. Only one randomized prospective blinded study examines sexual outcome in detail. MAIN MESSAGE: Testosterone is an important metabolic and sex hormone produced by the ovary throughout life. The variable reduction in ovarian testosterone production coincident with menopause is sometimes associated with a syndrome of specific changes in sexual desire and sexual response. Estrogen deficiency also impairs sexual response, but its replacement will not improve and might exacerbate sexual symptoms from androgen loss. Diagnosis of androgen deficiency is clinical, based on accurate assessment of a woman's sexual status before and after menopause and only confirmed (rather than diagnosed) by a low level of free testosterone. Partial androgen replacement restores much of the sexual response and facilitates sexual desire that is triggered by external cues. Avoiding supraphysiological levels of testosterone lessens risk of masculinization. Avoiding alkylated testosterone lessens hepatic or lipid impairment. CONCLUSION: Further prospective randomized studies of replacement of physiological levels of testosterone in women with androgen deficiency syndrome are needed, using formulations of testosterone available in Canada. The consistency of sexual changes, the associated personal and relationship distress, together with our clinical experience of the gratifying response to physiological replacement, make further studies urgently needed. PMID:10509222
Testosterone-related cortical maturation across childhood and adolescence.
Nguyen, Tuong-Vi; McCracken, James; Ducharme, Simon; Botteron, Kelly N; Mahabir, Megan; Johnson, Wendy; Israel, Mimi; Evans, Alan C; Karama, Sherif
2013-06-01
Neuroendocrine theories of brain development hold testosterone as the predominant factor mediating sex-specific cortical growth and the ensuing lateralization of hemispheric function. However, studies to date have focussed on prenatal testosterone rather than pubertal changes in testosterone. Yet, animal studies have shown a high density of androgen-sensitive receptors in multiple key cortical areas, and puberty is known to coincide with both a significant rise in testosterone and the emergence of behavioral sex differences, suggesting peripubertal influences of testosterone on brain development. Here, we used linear mixed models to examine sex-specific cortical maturation associated with changes in testosterone levels in a longitudinal sample of developmentally healthy children and adolescents. A significant "sex by age by testosterone" interaction on cortical thickness (CTh) involving widespread areas of the developing brain was found. Testosterone levels were associated with CTh changes in regions of the left hemisphere in males and of the right hemisphere in females. In both sexes, the relationship between testosterone and CTh varied across the age span. These findings show the association between testosterone and CTh to be complex, highly dynamic, and to vary, depending on sex and age; they also suggest sex-related hemispheric lateralization effects of testosterone in humans.
The Effect of Testosterone on Cardiovascular Biomarkers in the Testosterone Trials.
Mohler, Emile R; Ellenberg, Susan S; Lewis, Cora E; Wenger, Nanette K; Budoff, Matthew J; Lewis, Michael R; Barrett-Connor, Elizabeth; Swerdloff, Ronald S; Stephens-Shields, Alisa; Bhasin, Shalender; Cauley, Jane A; Crandall, Jill P; Cunningham, Glenn R; Ensrud, Kristine E; Gill, Thomas M; Matsumoto, Alvin M; Molitch, Mark E; Pahor, Marco; Preston, Peter E; Hou, Xiaoling; Cifelli, Denise; Snyder, Peter J
2018-02-01
Studies of the possible cardiovascular risk of testosterone treatment are inconclusive. To determine the effect of testosterone treatment on cardiovascular biomarkers in older men with low testosterone. Double-blind, placebo-controlled trial. Twelve academic medical centers in the United States. In all, 788 men ≥65 years old with an average of two serum testosterone levels <275 ng/dL who were enrolled in The Testosterone Trials. Testosterone gel, the dose adjusted to maintain the testosterone level in the normal range for young men, or placebo gel for 12 months. Serum markers of cardiovascular risk, including lipids and markers of glucose metabolism, fibrinolysis, inflammation, and myocardial damage. Compared with placebo, testosterone treatment significantly decreased total cholesterol (adjusted mean difference, -6.1 mg/dL; P < 0.001), high-density lipoprotein cholesterol (adjusted mean difference, -2.0 mg/dL; P < 0.001), and low-density lipoprotein cholesterol (adjusted mean difference, -2.3 mg/dL; P = 0.051) from baseline to month 12. Testosterone also slightly but significantly decreased fasting insulin (adjusted mean difference, -1.7 µIU/mL; P = 0.02) and homeostatic model assessment‒insulin resistance (adjusted mean difference, -0.6; P = 0.03). Testosterone did not change triglycerides, d-dimer, C-reactive protein, interleukin 6, troponin, glucose, or hemoglobin A1c levels more than placebo. Testosterone treatment of 1 year in older men with low testosterone was associated with small reductions in cholesterol and insulin but not with other glucose markers, markers of inflammation or fibrinolysis, or troponin. The clinical importance of these findings is unclear and requires a larger trial of clinical outcomes. Copyright © 2017 Endocrine Society
Relationship between testosterone levels and depressive symptoms in older men in Amirkola, Iran.
Kheirkhah, Farzan; Hosseini, Seyed Reza; Hosseini, Seyyedeh Fatemeh; Ghasemi, Nafiseh; Bijani, Ali; G Cumming, Robert
2014-01-01
Testosterone may be an important factor causing depression in the elderly men. The purpose of this study was to determine the relationship between testosterone levels and depressive symptoms in older men in Amirkola, Iran. This cross- sectional study is a part of the Amirkola Health and Aging Project (AHAP) that involves people aged 60 and above living in Amirkola, a small town in northern Iran. The testosterone levels were measured using ELISA on morning blood samples (ngr / ml) and depressive symptoms were identified using Geriatric Depression Scale (GDS). The data were collected and analyzed. Eight hundred thirty elderly men with the mean age of 70.02±7.7 years were included. On the basis of GDS criteria, 593 individuals had no depressive symptoms and 237 had at least one of these symptoms. The mean serum testosterone level in men without symptoms of depression (4.94±4.22) ngr/ml and was higher than in those with such symptoms (4.19±3.65) ngr/ml (P=0.011). Also, there was a significant inverse correlation between the testosterone levels and number of depressive symptoms (P=0.015, r=-0.084). After adjusting with age and educational levels, and living alone (OR=2.6, 95% CI: 1.17-5.82, P=0.02), testosterone levels (OR=1.67, 95% CI: 1.03-2.72, P=0.038) had the greatest impact on the development of depression. The results of this study showed a significant inverse relationship between serum testosterone levels and depressive symptoms in elderly men.
Raynaud, Julien; Schradin, Carsten
2014-04-22
Males of many species can adjust their behaviors to environmental conditions by changing reproductive tactics. Testosterone surges in adult breeding males typically inhibit the expression of paternal care while facilitating the expression of aggression during environmental changes. Similarly, in non-breeding philopatric males of cooperatively breeding species, up-regulation of testosterone may inhibit alloparental care while facilitating dispersal, i.e. males might become bolder and more explorative. We tested this hypothesis in philopatric male African striped mice, Rhabdomys pumilio. Striped mouse males can either remain in their natal groups providing alloparental care or they can disperse seeking mating opportunities. Compared to philopatric males, dispersed males typically show higher testosterone levels and lower corticosterone levels, and more aggression toward pups and same sex conspecifics. We experimentally increased the testosterone levels of the philopatric males kept in their family groups when pups were present. Testosterone-treated males did not differ significantly from control males in alloparental care and in aggression toward same-sex conspecifics. Compared to the control males, testosterone treated males were bolder, more active, and less anxious; they also showed lower corticosterone levels. The philopatric males were sensitive to our testosterone treatment for dispersal- and anxiety-like behavior but insensitive for social behaviors. Our results suggest a role of testosterone in dispersal. Copyright © 2014. Published by Elsevier Inc.
Tam, J; Danilovich, N; Nilsson, K; Sairam, M R; Maysinger, D
2002-01-01
The follitropin receptor knockout (FORKO) mouse undergoes ovarian failure, thereby providing an animal model to investigate the consequences of the depletion of circulating estrogen in females. The estrogen deficiency causes marked defects in the female reproductive system, obesity, and skeletal abnormalities. In light of estrogen's known pleiotropic effects in the nervous system, our study examined the effects of genetically induced estrogen-testosterone imbalance on this system in female FORKO mice. Circulating concentrations of 17-beta-estradiol (E2) in FORKO mice are significantly decreased (FORKO -/-: 1.13+/-0.34 pg/ml; wild-type +/+: 17.6+/-3.5 pg/ml, P<0.0001, n=32-41); in contrast, testosterone levels are increased (-/-: 37.7+/-2.3 pg/ml; wild-type +/+: 3.9+/-1.7 pg/ml, P<0.005, n=25-33). The focus was on the activities of key enzymes in the central cholinergic and peripheral nervous systems, on dorsal root ganglia (DRGs) capacity for neurite outgrowth, and on the phosphorylation state of structural neurofilament (NF) proteins. Choline acetyltransferase activity was decreased in several central cholinergic structures (striatum 50+/-3%, hippocampus 24+/-2%, cortex 12+/-3%) and in DRGs (11+/-6%). Moreover, we observed aberrations in the enzymatic activities of mitogen-activated protein kinases (extracellular-regulated kinase and c-Jun N-terminal kinase) in the hippocampus, DRGs, and sciatic nerves. Hippocampal and sensory ganglia samples from FORKO mice contained hyper-phosphorylated NFs. Finally, explanted ganglia of FORKO mice displayed decreased neurite outgrowth (20-50%) under non-treated conditions and when treated with E2 (10 nM). Our results demonstrate that genetic depletion of circulating estrogen leads to biochemical and morphological changes in central and peripheral neurons, and underlie the importance of estrogen in the normal development and functioning of the nervous system. In particular, the findings suggest that an early and persisting absence of the steroid leads to neurodegenerative changes and identify several key enzymes that may contribute to the process. This model provides a system to explore the consequences of circulating estrogen deprivation and other hormonal imbalances in the nervous system.
NIH-Supported Trials Test Hormonal Therapy in Older Men with Low Testosterone Levels
... February 18, 2016 NIH-supported trials test hormonal therapy in older men with low testosterone levels Testosterone ... Hadley, M.D., director of NIA’s Division of Geriatrics and Clinical Gerontology. “In contrast, though, the results ...
Alder, Nathan J; Keihani, Sorena; Stoddard, Gregory J; Myers, Jeremy B; Hotaling, James M
2018-06-06
To assess the efficacy and safety of combination therapy with clomiphene citrate (CC) and anastrozole (AZ) for male hypoandrogenism. We identified patients treated with a combination of CC + AZ in the period 2014 to 2017. Data were gathered on patient characteristics and laboratory values at baseline. Total testosterone, bioavailable testosterone, oestradiol and testosterone:oestradiol ratio were measured before combination therapy (treatment with CC only) and at CC + AZ combination therapy follow-ups. Treatment side effects were recorded; prostatic-specific antigen and haematocrit levels were measured to assess safety after 6 months. As a secondary outcome, semen characteristics were compared at baseline and after at least 3 months of combination therapy when these data were available. Data were analysed using a paired t-test and Wilcoxon's signed-rank test. A total of 51 men were included, with a mean age of 35.4 ± 7.4 years and a mean body mass index of 35.0 ± 8.0 kg/m 2 . After CC treatment, total testosterone, bioavailable testosterone, and oestradiol levels all significantly increased. AZ was added in all patients with hyperoestrogenaemia (oestradiol >50 pg/mL) or a testosterone:oestradiol ratio <10. CC + AZ therapy maintained therapeutic total testosterone and bioavailable testosterone levels while also normalizing oestradiol levels and testosterone:oestradiol ratio. Eleven patients experienced side effects: anxiety/irritability, n = 5; decreased libido, n = 4; elevated (>54%) haematocrit, n = 2. Combination therapy with CC + AZ is an effective and safe alternative for patients with elevated oestradiol level or low testosterone:oestradiol ratio. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.
Emeville, Elise; Giton, Frank; Giusti, Arnaud; Oliva, Alejandro; Fiet, Jean; Thomé, Jean-Pierre; Blanchet, Pascal; Multigner, Luc
2013-01-01
Background Studies relating long-term exposure to persistent organochlorine pollutants (POPs) with endocrine activities (endocrine disrupting chemicals) on circulating levels of steroid hormones have been limited to a small number of hormones and reported conflicting results. Objective We examined the relationship between serum concentrations of dehydroepiandrosterone, dehydroepiandrosterone sulphate, androstenedione, androstenediol, testosterone, free and bioavailable testosterone, dihydrotestosterone, estrone, estrone sulphate, estradiol, sex-hormone binding globulin, follicle-stimulating hormone, and luteinizing hormone as a function of level of exposure to three POPs known to interfere with hormone-regulated processes in different way: dichlorodiphenyl dichloroethene (DDE), polychlorinated biphenyl (PCB) congener 153, and chlordecone. Methods We collected fasting, morning serum samples from 277 healthy, non obese, middle-aged men from the French West Indies. Steroid hormones were determined by gas chromatography-mass spectrometry, except for dehydroepiandrosterone sulphate, which was determined by immunological assay, as were the concentrations of sex-hormone binding globulin, follicle-stimulating hormone and luteinizing hormone. Associations were assessed by multiple linear regression analysis, controlling for confounding factors, in a backward elimination procedure, in multiple bootstrap samples. Results DDE exposure was negatively associated to dihydrotestosterone level and positively associated to luteinizing hormone level. PCB 153 was positively associated to androstenedione and estrone levels. No association was found for chlordecone. Conclusions These results suggested that the endocrine response pattern, estimated by determining blood levels of steroid hormones, varies depending on the POPs studied, possibly reflecting differences in the modes of action generally attributed to these compounds. It remains to be investigated whether this response pattern is predictive of the subsequent occurrence of disease. PMID:23785499
Effects of two dominance manipulations on the stress response: Cognitive and embodied influences.
Deuter, Christian Eric; Schächinger, Hartmut; Best, Daniel; Neumann, Roland
2016-09-01
In response to stress, physiological and mental resources are allocated towards those systems that are needed for rapid responding in terms of fight or flight. On the other hand, long term regenerative processes such as growth, digestion and reproduction are attenuated. Levels of the sex steroid testosterone are reduced in participants that suffer from chronic stress. However, beyond its role for reproductive functions, testosterone plays an important role in the regulation of social status and dominance, testosterone levels increase during competition or when the social status is challenged. The Trier Social Stress Test (TSST), a laboratory stressor with a substantial social-evaluative component, can provoke an increase in salivary testosterone levels. Still, so far the reported findings regarding acute stress effects on testosterone are equivocal, possibly due to moderating effects. In this study we experimentally manipulated social dominance in 56 healthy participants (28m) by two independent manipulations (body posture and cognitive role taking) and subjected them to the TSST. We analyzed salivary testosterone and cortisol levels as dependent measures for the endocrine stress response. The role taking manipulation interacted with the testosterone response: we found the strongest increase when participants had to put themselves in a dominant (vs. submissive) role. Our results suggest that transient changes in testosterone levels during stress reflect a response to status threat that is affected by social dominance. Copyright © 2016 Elsevier B.V. All rights reserved.
Maternal salivary testosterone in pregnancy and fetal neuromaturation.
Voegtline, Kristin M; Costigan, Kathleen A; DiPietro, Janet A
2017-11-01
Testosterone exposure during pregnancy has been hypothesized as a mechanism for sex differences in brain and behavioral development observed in the postnatal period. The current study documents the natural history of maternal salivary testosterone from 18 weeks gestation of pregnancy to 6 months postpartum, and investigates associations with fetal heart rate, motor activity, and their integration. Findings indicate maternal salivary testosterone increases with advancing gestation though no differences by fetal sex were detected. High intra-individual stability in prenatal testosterone levels extend into the postnatal period, particularly for pregnancies with male fetuses. With respect to fetal development, by 36 weeks gestation higher maternal prenatal salivary testosterone was significantly associated with faster fetal heart rate and less optimal somatic-cardiac integration. Measurement of testosterone in saliva is a useful tool for repeated-measures studies of hormonal concomitants of pregnancy. Moreover, higher maternal testosterone levels are associated with modest interference to fetal neurobehavioral development. © 2017 Wiley Periodicals, Inc.
What does testosterone do for red deer males?
Malo, A.F.; Roldan, E.R.S.; Garde, J.J.; Soler, A.J.; Vicente, J.; Gortazar, C.; Gomendio, M.
2008-01-01
Testosterone has been proposed to have a dual effect, enhancing sexual traits while depressing parasite resistance in males. Here, we test this hypothesis in red deer, examining males from captive populations during the whole annual cycle and males from natural populations during the breeding season. We first explored the effects of body size, age and sampling date on testosterone to avoid confounding effects. Our results show that in captive populations seasonal changes in testosterone levels were mirrored by changes in testes size, and that during the rut there was a strong correlation between both. In natural populations, males with higher testosterone levels had larger testes, improved sperm quality, smaller burr diameter, stronger antlers, higher haematocrit levels, and increased nematode parasite load. By contrast, no significant relationship was found between testosterone and spleen size or tick parasite load. We conclude that testosterone (i) improves males' reproductive investment and physical stamina, (ii) improves antler strength but reduces burr diameter, and (iii) imposes a cost in terms of depressed parasite resistance. PMID:19129132
Gallo, Mia V.; Deane, Glenn D.; Nelder, Kyrie R.; DeCaprio, Anthony P.; Jacobs, Agnes
2013-01-01
Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized. Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to < 17 years of age with documented toxicant exposures. Methods: Data were collected between February 1996 and January 2000. Fasting blood specimens were collected before breakfast by trained Akwesasne Mohawk staff. Multivariable regression models were used to estimates associations between toxicants and serum testosterone, adjusted for other toxicants, Tanner stage, and potential confounders. Results: The sum of 16 PCB congeners (Σ16PCBs) that were detected in ≥ 50% of the population was significantly and negatively associated with serum testosterone levels, such that a 10% change in exposure was associated with a 5.6% decrease in testosterone (95% CI: –10.8, –0.5%). Of the 16 congeners, the more persistent ones (Σ8PerPCBs) were related to testosterone, whereas the less persistent ones, possibly reflecting more recent exposure, were not. When PCB congeners were subgrouped, the association was significant for the sum of eight more persistent PCBs (5.7% decrease; 95% CI: –11, –0.4%), and stronger than the sum of six less persistent congeners (3.1% decrease; 95% CI: –7.2, 0.9%). p,p´-DDE was positively but not significantly associated with serum testosterone (5.2% increase with a 10% increase in exposure; 95% CI: –0.5, 10.9%). Neither lead nor HCB was significantly associated with testosterone levels. Conclusions: Exposure to PCBs, particularly the more highly persistent congeners, may negatively influence testosterone levels among adolescent males. The positive relationship between p,p´-DDE and testosterone indicates that not all POPs act similarly. Citation: Schell LM, Gallo MV, Deane GD, Nelder KR, DeCaprio AP, Jacobs A; Akwesasne Task Force on the Environment. 2014. Relationships of polychlorinated biphenyls and dichlorodiphenyldichloroethylene (p,p´-DDE) with testosterone levels in adolescent males. Environ Health Perspect 122:304–309; http://dx.doi.org/10.1289/ehp.1205984 PMID:24398050
Diffuse traumatic brain injury affects chronic corticosterone function in the rat.
Rowe, Rachel K; Rumney, Benjamin M; May, Hazel G; Permana, Paska; Adelson, P David; Harman, S Mitchell; Lifshitz, Jonathan; Thomas, Theresa C
2016-07-01
As many as 20-55% of patients with a history of traumatic brain injury (TBI) experience chronic endocrine dysfunction, leading to impaired quality of life, impaired rehabilitation efforts and lowered life expectancy. Endocrine dysfunction after TBI is thought to result from acceleration-deceleration forces to the brain within the skull, creating enduring hypothalamic and pituitary neuropathology, and subsequent hypothalamic-pituitary endocrine (HPE) dysfunction. These experiments were designed to test the hypothesis that a single diffuse TBI results in chronic dysfunction of corticosterone (CORT), a glucocorticoid released in response to stress and testosterone. We used a rodent model of diffuse TBI induced by midline fluid percussion injury (mFPI). At 2months postinjury compared with uninjured control animals, circulating levels of CORT were evaluated at rest, under restraint stress and in response to dexamethasone, a synthetic glucocorticoid commonly used to test HPE axis regulation. Testosterone was evaluated at rest. Further, we assessed changes in injury-induced neuron morphology (Golgi stain), neuropathology (silver stain) and activated astrocytes (GFAP) in the paraventricular nucleus (PVN) of the hypothalamus. Resting plasma CORT levels were decreased at 2months postinjury and there was a blunted CORT increase in response to restraint induced stress. No changes in testosterone were measured. These changes in CORT were observed concomitantly with altered complexity of neuron processes in the PVN over time, devoid of neuropathology or astrocytosis. Results provide evidence that a single moderate diffuse TBI leads to changes in CORT function, which can contribute to the persistence of symptoms related to endocrine dysfunction. Future experiments aim to evaluate additional HP-related hormones and endocrine circuit pathology following diffuse TBI. © 2016 The authors.
High protein diets do not attenuate decrements in testosterone and IGF-I during energy deficit.
Henning, Paul C; Margolis, Lee M; McClung, James P; Young, Andrew J; Pasiakos, Stefan M
2014-05-01
Energy deficit (ED) diminishes fat-free mass (FFM) with concomitant reductions in anabolic hormone secretion. A modest increase in protein to recommended dietary allowance (RDA) levels during ED minimally attenuates decrements in insulin-like growth factor-I (IGF-I). The impact of dietary protein above the RDA on circulating anabolic hormones and their relationships with FFM in response to ED are not well described. Thirty-three adults were assigned diets providing protein at 0.8 (RDA), 1.6 (2×-RDA), and 2.4 (3×-RDA) g/kg/d for 31days. Testosterone, sex-hormone binding globulin (SHBG) and IGF-I system components were assessed after a 10-day period of weight-maintenance (WM) and after a 21-day period of ED (40%) achieved by an increase in energy expenditure and decreased energy intake. Associations between the change in FFM and anabolic hormone levels were determined. As compared to WM and regardless of dietary protein intake, total and free testosterone, total IGF-I, and acid-labile subunit decreased (P<0.05), whereas SHBG and IGF binding proteins-1, -2, and -3 increased (P<0.05) during ED. There were no energy-by-protein interactions on any hormones or IGF-I system components measured. Changes in FFM in response to ED were negatively associated with acid-labile subunit (ALS) (r=-0.62, P<0.05) in 2×-RDA; however, no other relationships were observed. Consuming a high protein diet does not impact the androgenic and IGF-I system response to ED. These data suggest that the protective effects of high protein diets on FFM during ED are likely not influenced by anabolic hormone concentrations. Published by Elsevier Inc.
Diffuse traumatic brain injury affects chronic corticosterone function in the rat
Rowe, Rachel K; Rumney, Benjamin M; May, Hazel G; Permana, Paska; Adelson, P David; Harman, S Mitchell; Lifshitz, Jonathan
2016-01-01
As many as 20–55% of patients with a history of traumatic brain injury (TBI) experience chronic endocrine dysfunction, leading to impaired quality of life, impaired rehabilitation efforts and lowered life expectancy. Endocrine dysfunction after TBI is thought to result from acceleration–deceleration forces to the brain within the skull, creating enduring hypothalamic and pituitary neuropathology, and subsequent hypothalamic–pituitary endocrine (HPE) dysfunction. These experiments were designed to test the hypothesis that a single diffuse TBI results in chronic dysfunction of corticosterone (CORT), a glucocorticoid released in response to stress and testosterone. We used a rodent model of diffuse TBI induced by midline fluid percussion injury (mFPI). At 2months postinjury compared with uninjured control animals, circulating levels of CORT were evaluated at rest, under restraint stress and in response to dexamethasone, a synthetic glucocorticoid commonly used to test HPE axis regulation. Testosterone was evaluated at rest. Further, we assessed changes in injury-induced neuron morphology (Golgi stain), neuropathology (silver stain) and activated astrocytes (GFAP) in the paraventricular nucleus (PVN) of the hypothalamus. Resting plasma CORT levels were decreased at 2months postinjury and there was a blunted CORT increase in response to restraint induced stress. No changes in testosterone were measured. These changes in CORT were observed concomitantly with altered complexity of neuron processes in the PVN over time, devoid of neuropathology or astrocytosis. Results provide evidence that a single moderate diffuse TBI leads to changes in CORT function, which can contribute to the persistence of symptoms related to endocrine dysfunction. Future experiments aim to evaluate additional HP-related hormones and endocrine circuit pathology following diffuse TBI. PMID:27317610
The relationship between sleep disorders and testosterone in men
Wittert, Gary
2014-01-01
Plasma testosterone levels display circadian variation, peaking during sleep, and reaching a nadir in the late afternoon, with a superimposed ultradian rhythm with pulses every 90 min reflecting the underlying rhythm of pulsatile luteinizing hormone (LH) secretion. The increase in testosterone is sleep, rather than circadian rhythm, dependent and requires at least 3 h of sleep with a normal architecture. Various disorders of sleep including abnormalities of sleep quality, duration, circadian rhythm disruption, and sleep-disordered breathing may result in a reduction in testosterone levels. The evidence, to support a direct effect of sleep restriction or circadian rhythm disruption on testosterone independent of an effect on sex hormone binding globulin (SHBG), or the presence of comorbid conditions, is equivocal and on balance seems tenuous. Obstructive sleep apnea (OSA) appears to have no direct effect on testosterone, after adjusting for age and obesity. However, a possible indirect causal process may exist mediated by the effect of OSA on obesity. Treatment of moderate to severe OSA with continuous positive airway pressure (CPAP) does not reliably increase testosterone levels in most studies. In contrast, a reduction in weight does so predictably and linearly in proportion to the amount of weight lost. Apart from a very transient deleterious effect, testosterone treatment does not adversely affect OSA. The data on the effect of sleep quality on testosterone may depend on whether testosterone is given as replacement, in supratherapeutic doses, or in the context abuse. Experimental data suggest that testosterone may modulate individual vulnerability to subjective symptoms of sleep restriction. Low testosterone may affect overall sleep quality which is improved by replacement doses. Large doses of exogenous testosterone and anabolic/androgenic steroid abuse are associated with abnormalities of sleep duration and architecture. PMID:24435056
Testosterone regulates bone response to inflammation.
Steffens, J P; Herrera, B S; Coimbra, L S; Stephens, D N; Rossa, C; Spolidorio, L C; Kantarci, A; Van Dyke, T E
2014-03-01
This study evaluated the alveolar bone response to testosterone and the impact of Resolvin D2 (RvD2) on testosterone-induced osteoblast function. For the in vivo characterization, 60 male adult rats were used. Treatments established sub-physiologic (L), normal (N), or supra-physiologic (H) concentrations of testosterone. Forty rats were subjected to orchiectomy; 20 rats received periodical testosterone injections while 20 rats received testicular sham-operation. Four weeks after the surgeries, 10 rats in each group received a subgingival ligature around the lower first molars to induce experimental periodontal inflammation and bone loss. In parallel, osteoblasts were differentiated from neonatal mice calvariae and treated with various doses of testosterone for 48 h. Cell lysates and conditioned media were used for the determination of alkaline phosphatase, osteocalcin, RANKL, and osteoprotegerin. Micro-computed tomography linear analysis demonstrated that bone loss was significantly increased for both L and H groups compared to animals with normal levels of testosterone. Gingival IL-1β expression was increased in the L group (p<0.05). Ten nM testosterone significantly decreased osteocalcin, RANKL, and OPG levels in osteoblasts; 100 nM significantly increased the RANKL:OPG ratio. RvD2 partially reversed the impact of 10 nM testosterone on osteocalcin, RANKL, and OPG. These findings suggest that both L and H testosterone levels increase inflammatory bone loss in male rats. While low testosterone predominantly increases the inflammatory response, high testosterone promotes a higher osteoblast-derived RANKL:OPG ratio. The proresolving mediator RvD2 ameliorates testosterone-derived downregulation of osteocalcin, RANKL, and OPG in primary murine osteoblasts suggesting a direct role of inflammation in osteoblast function. © Georg Thieme Verlag KG Stuttgart · New York.
The hormonal correlates of implicit power motivation
Stanton, Steven J.; Schultheiss, Oliver C.
2009-01-01
Attempts to link testosterone to dominance dispositions using self-report measures of dominance have yielded inconsistent findings. Similarly, attempts to link testosterone changes to a situational outcome like winning or losing a dominance contest have yielded inconsistent findings. However, research has consistently shown that an indirect measure of an individual’s dominance disposition, implicit power motivation, is positively related to baseline testosterone levels and, in interaction with situational outcomes, predicts testosterone changes. We propose a hormonal model of implicit power motivation that describes how testosterone levels change as an interactive function of individuals’ implicit power motivation and dominance situations. We also propose that estradiol, and not testosterone, plays a key role in dominance motivation in women. PMID:20161646
Theorell, T; Karasek, R A; Eneroth, P
1990-01-01
Job strain, a high level of psychological demands combined with a low level of decision latitude, has been hypothesized to induce mobilization of energy and inhibition of anabolism. In the present project this hypothesis was tested using four repeated observations every third month in a group of 44 men working in six widely different occupations. On each occasion scores of self-reported demands and decision latitude were calculated for every participant. An earlier report has shown that systolic blood pressure during work hours--an indicator of mobilization of energy--increased with increasing job strain (ratio between demands and decision latitude). Blood samples were drawn in the morning at the work site. For each man the plasma testosterone levels--representing the general level of anabolic activity--on the two occasions with the worst strain (ratio between demands and decision latitude) were compared with the plasma testosterone levels on the two occasions with the least strain. The results indicated that total plasma testosterone (but not free testosterone) levels increased when strain diminished in sedentary but not in physically demanding work. Subjects with a family history of hypertension showed a greater decrease in testosterone levels than others when job strain increased.
External Beam Radiotherapy Affects Serum Testosterone in Patients With Localized Prostate Cancer.
Pompe, Raisa S; Karakiewicz, Pierre I; Zaffuto, Emanuele; Smith, Ariane; Bandini, Marco; Marchioni, Michele; Tian, Zhe; Leyh-Bannurah, Sami-Ramzi; Schiffmann, Jonas; Delouya, Guila; Lambert, Carole; Bahary, Jean-Paul; Beauchemin, Marie Claude; Barkati, Maroie; Ménard, Cynthia; Graefen, Markus; Saad, Fred; Tilki, Derya; Taussky, Daniel
2017-07-01
Previous studies have examined testosterone levels after external beam radiation (EBRT) monotherapy, but since 2002 only sparse contemporary data have been reported. To examine testosterone kinetics in a large series of contemporary patients after EBRT. The study was conducted in 425 patients who underwent definitive EBRT for localized prostate cancer from 2002 through 2014. Patients were enrolled in several phase II and III trials. Exclusion criteria were neoadjuvant or adjuvant androgen-deprivation therapy or missing data. Testosterone was recorded at baseline and then according to each study protocol (not mandatory in all protocols). Statistical analyses consisted of means and proportions, Kaplan-Meier plots, and logistic and Cox regression analyses. Testosterone kinetics after EBRT monotherapy and their influence on biochemical recurrence. Median follow-up of 248 assessable patients was 72 months. One hundred eighty-six patients (75.0%) showed a decrease in testosterone. Median time to first decrease was 6.4 months. Median percentage of decrease to the nadir was 30% and 112 (45.2%) developed biochemical hypogonadism (serum testosterone < 8 nmol/L). Of all patients with testosterone decrease, 117 (62.9%) recovered to at least 90% of baseline levels. Advanced age, increased body mass index, higher baseline testosterone level, and lower nadir level were associated with a lower chance of testosterone recovery. Subgroup analyses of 166 patients treated with intensity-modulated radiotherapy confirmed the results recorded for the entire cohort. In survival analyses, neither testosterone decrease nor recovery was predictive for biochemical recurrence. EBRT monotherapy influences testosterone kinetics, and although most patients will recover, approximately 45% will have biochemical hypogonadism. We report on the largest contemporary series of patients treated with EBRT monotherapy in whom testosterone kinetics were ascertained. Limitations are that testosterone follow-up was not uniform and the study lacked information on health-related quality-of-life data. Our findings indicate that up to 75% of patients will have a profound testosterone decrease, with up to a 40% increase in rates of biochemical hypogonadism, although the latter events will leave biochemical recurrence unaffected. Pompe RS, Karakrewicz PI, Zaffuto E, et al. External Beam Radiotherapy Affects Serum Testosterone in Patients With Localized Prostate Cancer. J Sex Med 2017;14:876-882. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Escallón, Camilo; Weinstein, Nicole M; Tallant, James A; Wojtenek, Winfried; Rodríguez-Saltos, Carlos A; Bonaccorso, Elisa; Moore, Ignacio T
2016-10-01
Elevation has been proposed as a dominant ecological variable shaping life history traits and subsequently their underlying hormonal mechanisms. In an earlier meta-analysis of tropical birds, elevation was positively related to testosterone levels. Furthermore, parasitism by avian haemosporidians should vary with elevation as environmental conditions affect vector abundance, and while testosterone is needed for breeding, it is hypothesized to be immunosuppressive and thus could exacerbate haemosporidian infection. Our objective in this study was to examine the relationships between elevation, testosterone levels, and parasitism by avian haemosporidians. We surveyed breeding male rufous-collared sparrows (Zonotrichia capensis) across a wide elevational range along the equator. We measured baseline testosterone levels, haemosporidian infection at four elevations spanning the species' natural range in the Ecuadorian Andes (600, 1500, 2100, 3300 m). Testosterone levels from breeding males were not related to elevation, but there was high intrapopulation variability. Testosterone levels were not related to the probability of parasitism, but our results from one population suggested that the likelihood of being infected by haemosporidian parasites was greater when in breeding condition. In conclusion, even though there is variation in life history strategies among the studied populations, wider divergence in seasonality and life history traits would probably be needed to detect an effect of elevation on testosterone if one exists. Additionally, our results show that variation in testosterone is not related to infection risk of haemosporidians, thus other factors that take a toll on energetic resources, such as reproduction, should be looked at more closely. © 2016 Wiley Periodicals, Inc.
Pham, Nathan H; Bena, James; Bhatt, Deepak L; Kennedy, Laurence; Schauer, Philip R; Kashyap, Sangeeta R
2018-01-01
Hypogonadism frequently occurs in male patients with type 2 diabetes (T2DM) and is linked to insulin resistance and inflammation. Testosterone levels rise acutely in obese patients following bariatric surgery, though long-term changes have not been investigated in a randomized controlled trial. This study evaluated obese men with T2DM randomized to either bariatric surgery or medical therapy. Testosterone, gonadotropins, body composition, insulin sensitivity, and inflammatory markers were evaluated in 32 patients at baseline and at 5 years. Surgical patients had 47.4% increase in free testosterone compared to medical therapy patients who had 2.2% decrease (P = 0.013). Increase in free testosterone correlated with reduction in body weight, high-sensitivity C-reactive protein (hsCRP), and leptin levels. Prolonged improvements in testosterone levels after bariatric surgery in T2DM are found to be related to reduction in body weight and adipogenic inflammation.
George, Elizabeth M; Rosvall, Kimberly A
2018-06-02
In many vertebrates, males increase circulating testosterone (T) levels in response to seasonal and social changes in competition. Females are also capable of producing and responding to T, but the full extent to which they can elevate T across life history stages remains unclear. Here we investigated T production during various breeding stages in female tree swallows (Tachycineta bicolor), which face intense competition for nesting sites. We performed GnRH and saline injections and compared changes in T levels 30 min before and after injection. We found that GnRH-injected females showed the greatest increases in T during territory establishment and pre-laying stages, whereas saline controls dramatically decreased T production during this time. We also observed elevated rates of conspecific aggression during these early stages of breeding. During incubation and provisioning, however, T levels and T production capabilities declined. Given that high T can disrupt maternal care, an inability to elevate T levels in later breeding stages may be adaptive. Our results highlight the importance of saline controls for contextualizing T production capabilities, and they also suggest that social modulation of T is a potential mechanism by which females may respond to competition, but only during the period of time when competition is most intense. These findings have broad implications for understanding how females can respond to their social environment and how selection may have shaped these hormone-behavior interactions. Copyright © 2018 Elsevier Inc. All rights reserved.
Prevalence of androgen deficiency in men with erectile dysfunction.
Köhler, Tobias S; Kim, Johnny; Feia, Kendall; Bodie, Josh; Johnson, Nick; Makhlouf, Antoine; Monga, Manoj
2008-04-01
Erectile dysfunction (ED) and androgen deficiency in aging men are two separate clinical entities that often overlap. Controversy exists regarding the most appropriate total testosterone level that defines androgen deficiency in aging men, and its prevalence in men with ED is still uncertain. We evaluated the prevalence and risk factors of low and low-normal testosterone levels in men presenting for an initial ED evaluation. The computerized charts from 1987 to 2002 of 2794 men aged 25 to 80 years and presenting with a primary complaint of ED who also had serum total testosterone levels measured were retrospectively reviewed. Multiple testosterone level cutpoints and a linear regression model (including age, diabetes, cholesterol, anemia, creatinine, and prostate-specific antigen) were used to analyze the factors that correlated with hypogonadism. The prevalence of androgen deficiency was 7%, 23%, 33%, and 47% for testosterone levels of less than 200, less than 300, less than 346, and less than 400 ng/dL, respectively. An abrupt increase in hypogonadism prevalence occurred in men aged 45 to 50, beyond which a plateau of prevalence was maintained until older than 80 years of age. Age, the presence of uncontrolled diabetes, high total cholesterol, and anemia all correlated with significantly decreased testosterone levels in men with ED. The prostate-specific antigen level and creatinine did not affect the testosterone levels. Androgen deficiency was quite common in men presenting with ED and correlated significantly with age, uncontrolled diabetes, hypercholesteremia, and anemia. Although additional prospective studies evaluating the effect of testosterone supplementation in this population are needed, clinicians, including urologists, should be keenly aware of the large overlap of patients with ED who might also have the entity, androgen deficiency in the aging male.
Gu, Tao; Wen, Zongmei; Xu, Shufeng; Hua, Haixia; Zhang, Zhi; Wen, Tao; Fu, Zhanzhao; Lv, Xin
2014-06-01
An early differentiation of malignant from benign solitary pulmonary nodules (SPNs) is essential for management and prognosis of lung cancer. Here we investigated whether measurement of circulating sex hormones could be useful for an early detection of malignancy among patients with SPNs. We recruited 47 patients with malignant SPNs 45 patients with benign SPNs, and 32 healthy persons. Testosterone, estradiol, and progesterone were measured. Carcinoembryonic antigen (CEA) as well as TNF-α, IL-1 and IL-6 were also measured. We found that sex hormones were decreased significantly in patients with malignant SPNs, as compared to patients with benign SPNs and healthy controls (P<0.05). Sex hormones levels showed a trend to decline in patients with benign SPNs as compared to normal controls, but the difference was not statistically significant (P>0.05). CEA levels were only abnormally elevated in eight patients with lung adenocarcinoma. The inflammatory cytokines were remarkably higher in both patients than in normal controls. However, there was no statistical difference in these cytokines among patients. The reduced sex hormones levels seemed to be uniquely associated with lung cancer. Therefore, measurement of sex hormones may have clinical potential in the diagnosis of malignancy in patients with SPNs.
Separham, Ahmad; Ghaffari, Samad; Sohrabi, Bahram; Aslanabadi, Naser; Hadavi Bavil, Mozhgan; Lotfollahi, Hasanali
2017-01-01
Low level of testosterone may be associated with cardiovascular diseases in men, as some evidence suggests a protective role for testosterone in cardiovascular system. Little is known about the possible role of serum testosterone in response to reperfusion therapy in ST-elevation myocardial infarction (STEMI) and its relationship with ST-segment recovery. The present study was conducted to evaluate the association of serum testosterone levels with ST-segment resolution following primary percutaneous coronary intervention (PPCI) in male patients with acute STEMI. Forty-eight men (mean age 54.55 ± 12.20) with STEMI undergoing PPCI were enrolled prospectively. Single-lead ST segment resolution in the lead with maximum baseline ST-elevation was measured and patients were divided into two groups according to the degree of ST-segment resolution: complete (> or =50%) or incomplete (<50%). The basic and demographic data of all patients, their left ventricular ejection fraction (LVEF) and laboratory findings including serum levels of free testosterone and cardiac enzymes were recorded along with angiographic finding and baseline TIMI (Thrombolysis in Myocardial Infarction) flow and also in-hospital complications and then these variables were compared between two groups. A complete ST-resolution (≥50%) was observed in 72.9% of the patients. The serum levels of free testosterone ( P = 0.04), peak cardiac troponin ( P = 0.03) were significantly higher and hs-CRP ( P = 0.02) were lower in patients with complete ST-resolution compared to those with incomplete ST-resolution. In-hospital complications were observed in 31.2% of patients. The patients with a lower baseline TIMI flow ( P = 0.03) and those who developed complications ( P = 0.04) had lower levels of free testosterone. A significant positive correlation was observed between the left ventricular function and serum levels of free testosterone ( P = 0.01 and r = +0.362). This study suggests that in men with STEMI undergoing PPCI, higher serum levels of testosterone are associated with a better reperfusion response, fewer complications and a better left ventricular function.
Singh, Darshan; Murugaiyah, Vikneswaran; Hamid, Shahrul Bariyah Sahul; Kasinather, Vicknasingam; Chan, Michelle Su Ann; Ho, Eric Tatt Wei; Grundmann, Oliver; Chear, Nelson Jeng Yeou; Mansor, Sharif Mahsufi
2018-07-15
Mitragyna speciosa (Korth.) also known as kratom, is a native medicinal plant of Southeast Asia with opioid-like effects. Kratom tea/juice have been traditionally used as a folk remedy and for controlling opiate withdrawal in Malaysia. Long-term opioid use is associated with depletion in testosterone levels. Since kratom is reported to deform sperm morphology and reduce sperm motility, we aimed to clinically investigate the testosterone levels following long-term kratom tea/juice use in regular kratom users. A total of 19 regular kratom users were recruited for this cross-sectional study. A full-blood test was conducted including determination of testosterone level, follicle stimulating hormone (FSH) and luteinizing hormone (LH) profile, as well as hematological and biochemical parameters of participants. We found long-term kratom tea/juice consumption with a daily mitragynine dose of 76.23-94.15 mg did not impair testosterone levels, or gonadotrophins, hematological and biochemical parameters in regular kratom users. Regular kratom tea/juice consumption over prolonged periods (>2 years) was not associated with testosterone impairing effects in humans. Copyright © 2018 Elsevier B.V. All rights reserved.
Marriage and motherhood are associated with lower testosterone concentrations in women
Barrett, Emily S.; Tran, Van; Thurston, Sally; Jasienska, Grazyna; Furberg, Anne-Sofie; Ellison, Peter T.; Thune, Inger
2012-01-01
Testosterone has been hypothesized to modulate the trade-off between mating and parenting effort in males. Indeed, evidence from humans and other pair-bonded species suggests that fathers and men in committed relationships have lower testosterone levels than single men and men with no children. To date, only one published study has examined testosterone in relation to motherhood, finding that mothers of young children have lower testosterone than non-mothers. Here, we examine this question in 195 reproductive-age Norwegian women. Testosterone was measured in morning serum samples taken during the early follicular phase of the menstrual cycle, and marital and maternal status were assessed by questionnaire. Mothers of young children (age ≤3) had 14% lower testosterone than childless women and 19% lower testosterone than women who only had children over age 3. Among mothers, age of the youngest child strongly predicted testosterone levels. There was a trend towards lower testosterone among married women compared to unmarried women. All analyses controlled for body mass index (BMI), age, type of testosterone assay, and time of serum sample collection. This is the first study to look at testosterone concentrations in relation to marriage and motherhood in Western women, and it suggests that testosterone may differ with marital and maternal status in women, providing further corroboration of previous findings in both sexes. PMID:23123222
Pelton, Kristine; Freeman, Michael R.; Montgomery, R. Bruce
2012-01-01
Prostate cancer (PCa) is the second most common cancer in men. Androgen deprivation therapy (ADT) leads to tumor involution and reduction of tumor burden. However, tumors eventually reemerge that have overcome the absence of gonadal androgens, termed castration resistant PCa (CRPC). Theories underlying the development of CRPC include androgen receptor (AR) mutation allowing for promiscuous activation by non-androgens, AR amplification and overexpression leading to hypersensitivity to low androgen levels, and/or tumoral uptake and conversion of adrenally derived androgens. More recently it has been proposed that prostate tumor cells synthesize their own androgens through de novo steroidogenesis, which involves the step-wise synthesis of androgens from cholesterol. Using the in vivo LNCaP PCa xenograft model, previous data from our group demonstrated that a hypercholesterolemia diet potentiates prostatic tumor growth via induction of angiogenesis. Using this same model we now demonstrate that circulating cholesterol levels are significantly associated with tumor size (R = 0.3957, p = 0.0049) and intratumoral levels of testosterone (R = 0.41, p = 0.0023) in LNCaP tumors grown in hormonally intact mice. We demonstrate tumoral expression of cholesterol uptake genes as well as the spectrum of steroidogenic enzymes necessary for androgen biosynthesis from cholesterol. Moreover, we show that circulating cholesterol levels are directly correlated with tumoral expression of CYP17A, the critical enzyme required for de novo synthesis of androgens from cholesterol (R = 0.4073, p = 0.025) Since hypercholesterolemia does not raise circulating androgen levels and the adrenal gland of the mouse synthesizes minimal androgens, this study provides evidence that hypercholesterolemia increases intratumoral de novo steroidogenesis. Our results are consistent with the hypothesis that cholesterol-fueled intratumoral androgen synthesis may accelerate the growth of prostate tumors, and suggest that treatment of CRPC may be optimized by inclusion of cholesterol reduction therapies in conjunction with therapies targeting androgen synthesis and the AR. PMID:22279565
Adelman, James Stephen; Moore, Ignacio Tomás; Hawley, Dana Michelle
2015-01-01
Aggression can alter infectious disease dynamics through two, non-exclusive mechanisms: 1) increasing direct contact among hosts and 2) altering hosts' physiological response to pathogens. Here we examined the latter mechanism in a social songbird by manipulating intraspecific aggression in the absence of direct physical contact. We asked whether the extent of aggression an individual experiences alters glucocorticoid levels, androgen levels, and individual responses to infection in an ecologically relevant disease model: house finches (Haemorhous mexicanus) infected with Mycoplasma gallisepticum (MG). Wild-caught male finches were housed in one of three settings, designed to produce increasing levels of aggression: 1) alone, with no neighbor ("no neighbor"), 2) next to a sham-implanted stimulus male ("sham neighbor"), or 3) next to a testosterone-implanted stimulus male ("testosterone neighbor"). Following one week of social treatment, focal males were experimentally infected with MG, which causes severe conjunctivitis and induces sickness behaviors such as lethargy and anorexia. While social treatment increased aggression as predicted, there were no differences among groups in baseline corticosterone levels, total circulating androgens, or responses to infection. Across all focal individuals regardless of social treatment, pre-infection baseline corticosterone levels were negatively associated with the severity of conjunctivitis and sickness behaviors, suggesting that corticosterone may dampen inflammatory responses in this host-pathogen system. However, because corticosterone levels differed based upon population of origin, caution must be taken in interpreting this result. Taken together, these results suggest that in captivity, although aggression does not alter individual responses to MG, corticosterone may play a role in this disease. © 2014 Wiley Periodicals, Inc.
Muraleedharan, Vakkat; Marsh, Hazel; Kapoor, Dheeraj; Channer, Kevin S; Jones, T Hugh
2013-12-01
Men with type 2 diabetes are known to have a high prevalence of testosterone deficiency. No long-term data are available regarding testosterone and mortality in men with type 2 diabetes or any effect of testosterone replacement therapy (TRT). We report a 6-year follow-up study to examine the effect of baseline testosterone and TRT on all-cause mortality in men with type 2 diabetes and low testosterone. A total of 581 men with type 2 diabetes who had testosterone levels performed between 2002 and 2005 were followed up for a mean period of 5.81.3 S.D. years. mortality rates were compared between total testosterone 10.4nmol/l (300ng/dl; n=343) and testosterone 10.4nmol/l (n=238). the effect of TRT (as per normal clinical practise: 85.9% testosterone gel and 14.1% intramuscular testosterone undecanoate) was assessed retrospectively within the low testosterone group. Mortality was increased in the low testosterone group (17.2%) compared with the normal testosterone group (9%; P=0.003) when controlled for covariates. In the Cox regression model, multivariate-adjusted hazard ratio (HR) for decreased survival was 2.02 (P=0.009, 95% CI 1.2-3.4). TRT (mean duration 41.6±20.7 months; n=64) was associated with a reduced mortality of 8.4% compared with 19.2% (P=0.002) in the untreated group (n=174). The multivariate-adjusted HR for decreased survival in the untreated group was 2.3 (95% CI 1.3-3.9, P=0.004). Low testosterone levels predict an increase in all-cause mortality during long-term follow-up. Testosterone replacement may improve survival in hypogonadal men with type 2 diabetes.
Bhongade, M B; Prasad, S; Jiloha, R C; Ray, P C; Mohapatra, S; Koner, B C
2015-04-01
The present study evaluated the effect of psychological stress on male fertility hormones and seminal quality in male partner of infertile couples. Seventy male partners of infertile couples were evaluated for level of psychological stress using Hospital Anxiety and Depression Score (HADS) questionnaire, serum total testosterone, luteinising hormone (LH) and follicle-stimulating hormone (FSH) by electrochemiluminescence assay and serum GnRH by ELISA. Seminal analysis was performed as per WHO guideline. Nineteen (27%) of them had HADS anxiety and depression score ≥8 (abnormal HADS score). The persons having abnormal HADS had lower serum total testosterone, higher serum FSH and LH than those of persons having normal HADS. Serum total testosterone correlated negatively with HADS, but LH and FSH correlated positively. There was no change in GnRH with the change in stress or testosterone levels. Sperm count, motility and morphologically normal spermatozoa were lower in persons having abnormal HADS. Sperm count correlated positively with total testosterone and negatively with FSH and LH. Abnormal sperm motility and morphology were related to lower testosterone and higher LH and FSH levels. Psychological stress primarily lowers serum total testosterone level with secondary rise in serum LH and FSH levels altering seminal quality. Stress management is warranted for male infertility cases. © 2014 Blackwell Verlag GmbH.
Zang, Zhi Jun; Ji, Su Yun; Dong, Wang; Zhang, Ya Nan; Zhang, Er Hong; Bin, Zhang
2015-06-01
Late-onset hypogonadism (LOH) is a clinical syndrome characterized with aging and declined serum testosterone levels. Sexual symptoms are also essential for the diagnosis of LOH. Testosterone replacement therapy is used widely to treat LOH. However, the side effects of it should not be ignored, such as fluid retention, hypertension and spermatogenic suppression. Therefore, alternate treatment modalities have been pursued. Herbal medicines used widely in China have achieved satisfying results with little side effects. Nonetheless, there are few pharmacological researches on them. In this study, 24-month-old mice were used as LOH animal models to explore the pharmacological effects of a herbal medicine, saikokaryukotsuboreito (SKRBT), on serum testosterone levels and sexual functions. Furthermore, the expression of steroidogenic acute regulatory (StAR) protein, a kind of rate-limiting enzyme of testosterone synthesis, was also examined. As a result, SKRBT improved the serum testosterone levels of these mice at a dose of 300 and 450 mg/kg. Multiple measures of sexual behavior were enhanced. The expression of StAR was also increased. Therefore, this study suggested that SKRBT can improve the serum testosterone levels by activating the expression of StAR and might be a viable option to treat sexual symptoms caused by LOH.
Apfelbeck, Beate; Mortega, Kim G; Flinks, Heiner; Illera, Juan Carlos; Helm, Barbara
2017-04-17
Testosterone facilitates physiological, morphological, and behavioral changes required for breeding in male vertebrates. However, testosterone concentrations and the link between its seasonal changes and those in reproductive behaviors vary greatly among species. To better understand the impact of tropical and temperate environments and life history factors on this variation, we have compared testosterone, territorial behavior and song performance across sequential stages of the breeding season in males of 16 closely related taxa of East African tropical and West European temperate stonechats (Saxicola spp), which all breed during a short breeding season, but differ in migratory behavior, seasonal territory-acquisition and pace of life. We found that generally, the profiles of testosterone and territorial behavior were similar across latitudes. African stonechats with a slow pace of life had equally high peak testosterone concentrations and responded as aggressively to an intruder as European stonechats with a fast pace of life. However, song performance at the beginning of the breeding season was lower in African than in European stonechats. The differences in song performance were not associated with variation in testosterone levels between tropical and temperate stonechats. The results suggest a very similar role for testosterone as a mediator of high intensity territorial aggression during the fertile period of females in tropical and temperate stonechats, which all are highly seasonal, locally synchronous breeders. A potential explanation may be high risk of extra-pair copulations which has been associated with synchronous breeding. Interestingly, an association was not consistent for song performance. Our data suggest that song performance can be disassociated from peak testosterone levels depending on its role in breeding behavior. Despite similar testosterone levels, European males, which early in the breeding season acquire territories and mates, showed greater song performance than African stonechats, which maintain year-round territories and pair-bonds. Taken together, our study comparing related taxa of old world songbirds suggests that short breeding seasons may be a major selective force for high peak testosterone levels during breeding regardless of latitude and pace of life, but that particular behaviors, in our case song, can be uncoupled from peak testosterone levels.
Auger, Catherine J.; Coss, Dylan; Auger, Anthony P.; Forbes-Lorman, Robin M.
2011-01-01
Although some DNA methylation patterns are altered by steroid hormone exposure in the developing brain, less is known about how changes in steroid hormone levels influence DNA methylation patterns in the adult brain. Steroid hormones act in the adult brain to regulate gene expression. Specifically, the expression of the socially relevant peptide vasopressin (AVP) within the bed nucleus of the stria terminalis (BST) of adult brain is dependent upon testosterone exposure. Castration dramatically reduces and testosterone replacement restores AVP expression within the BST. As decreases in mRNA expression are associated with increases in DNA promoter methylation, we explored the hypothesis that AVP expression in the adult brain is maintained through sustained epigenetic modifications of the AVP gene promoter. We find that castration of adult male rats resulted in decreased AVP mRNA expression and increased methylation of specific CpG sites within the AVP promoter in the BST. Similarly, castration significantly increased estrogen receptor α (ERα) mRNA expression and decreased ERα promoter methylation within the BST. These changes were prevented by testosterone replacement. This suggests that the DNA promoter methylation status of some steroid responsive genes in the adult brain is actively maintained by the presence of circulating steroid hormones. The maintenance of methylated or demethylated states of some genes in the adult brain by the presence of steroid hormones may play a role in the homeostatic regulation of behaviorally relevant systems. PMID:21368111
Wu, Yin; Yang, Hongfang; Wang, Xiaohui
2017-09-01
Our previous study demonstrated that treatment with Tribulus terrestris (TT) extracts (120 mg/kg) promoted the muscle weight gain and performance of rats undergoing high intensity exercise. The present study was designed to explore the mechanisms underlying the effect of treatment with TT extracts and the involvement of androgens, the androgen receptor (AR), insulin growth factor‑1 (IGF‑1) and the IGF‑1 receptor (IGF‑1R). A total of 32 Sprague‑Dawley rats were randomly divided into groups as follows: Control; TT, treated with TT extracts, E, high intensity exercise; E+TT, high intensity exercise plus TT treatment. The rats of the E and E+TT groups underwent high intensity exercise with a progressively increasing load for 5 weeks, and TT extracts were intragastrically administered in the TT and E+TT rats 30 min prior to training. TT extract composition was analyzed using ultra‑high performance liquid chromatography‑quadrupole‑time of flight mass spectrometry. Testosterone and IGF‑1 plasma levels and AR, IGF‑1R and myosin heavy chain (MHC) protein levels in muscles were determined by ELISA and western blotting, respectively. The saponins tigogenin and diosgenin comprised ~71.35% of the total peak area. Compared with the E group, TT extracts increased the testosterone and IGF‑1 plasma levels, and AR, IGF‑1R and MHC protein levels in the gastrocnemius of rats undergoing high intensity exercise, accompanied with increased body weight and gastrocnemius weight. In conclusion, the effect of TT extracts on the performance of high intensity exercise rats may be attributed to increased levels of circulating testosterone and IGF‑1 and increased AR and IGF‑1R protein expression levels in the gastrocnemius, resulting in increased muscle weight and increased MHC in the gastrocnemius. The present study provided preliminary evidence supporting the use of TT extracts as a dietary supplement for the promotion of skeletal muscle mass increase and the enhancement of athletic performance in humans performing high intensity exercise.
Chang, Wei-Hsiang; Li, Sih-Syuan; Wu, Meng-Hsing; Pan, Hsien-An; Lee, Ching-Chang
2015-11-01
Do phthalates create a male reproductive hormone imbalance by down-regulating the secretion of testosterone and insulin-like factor 3 (INSL3)? Our study suggests that exposure to phthalates is related to a reduction in the secretion of testosterone and INSL3 in adult males. There is evidence that exposure to phthalates, an abundant group of industrial plasticizers, negatively affects testosterone biosynthesis, but little is known about the mechanism in men. The hypothesis that exposure to phthalates reduces the levels of testosterone and INSL3, a marker of Leydig cell function, is underexplored. This case-control study of 176 men ran from 2010 to 2012. Infertile men were recruited through infertility clinics in Taiwan, fertile men were recruited from childbirth preparation classes and all were categorized based on the World Health Organization definition of infertility and by the diagnoses of obstetricians. Urinary concentrations of 11 phthalate metabolites were measured, along with serum levels of FSH, LH, total testosterone (TT), estradiol, sex hormone-binding globulin and Inhibin B. Androgen status indices including free testosterone (fT) and the free androgen index (FAI) were calculated. The circulating INSL3 level was evaluated using a radioimmunoassay. Non-parametric analyses, trend tests and linear regression models were used. Urinary mono-n-butyl phthalate (MnBP), mono-(2-ethylhexyl) phthalate (MEHP) and mono-2-ethyl-5-carboxypentyl phthalate were significantly higher in infertile than in fertile men. Serum Inhibin B, the Inhibin B : FSH ratio, the TT : LH ratio and INSL3 were significantly lower in infertile men. In multiple regression models controlled for potential confounders, there is an inverse association between urinary levels of mono-methyl phthalate (MMP), mono-iso-butyl phthalate (MiBP), MEHP, MEHP% and serum TT (P = 0.001, 0.007, 0.042 and 0.012, respectively). The inverse associations were also found between urinary levels of MiBP, monobenzyl phthalate (MBzP), MEHP, MEHP% and serum fT (P = 0.028, 0.017, 0.045 and 0.027, respectively); between urinary levels of MMP, MEHP, MEHP% and the TT : LH ratio (P = 0.004, 0.029 and 0.039, respectively); between urinary levels of MMP, MiBP, MnBP, MBzP, MEHP and the FAI (P = 0.002, 0.008, 0.037, 0.028, 0.042 and 0.016, respectively). Urinary MBzP and MEHP% were negatively associated with a decrease in serum INSL3 (P = 0.049 and <0.001). We also observed a strong inverse relationship between MEHP% quartiles and serum TT, fT, the TT : LH ratio and INSL3 (Ptrend = 0.003, 0.080, 0.002 and 0.012, respectively). Serum INSL3, TT, fT and the TT : LH ratio were lower for men in the highest MEHP% quartile than in the reference group (P = 0.007, 0.002, 0.090 and 0.001, respectively). A potential limitation is using a single urine and blood sample to predict urinary phthalate metabolites and reproductive hormone status over long periods. However, there is evidence that a single measure provides a reliable result in population studies. Non-occupational exposure to phthalates, including di-2-ethylhexyl phthalate, might lead to adverse effects on testicular/Leydig cell function and be of concern owing to the ubiquitous multisource exposure to phthalates among the general population. Although our findings are in agreement with recent experimental data, more studies are required to draw firm conclusions on the relation of INSL3 to phthalate exposure or testicular/Leydig cell function. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Basal testosterone, leadership and dominance: A field study and meta-analysis.
van der Meij, Leander; Schaveling, Jaap; van Vugt, Mark
2016-10-01
This article examines the role of basal testosterone as a potential biological marker of leadership and hierarchy in the workplace. First, we report the result of a study with a sample of male employees from different corporate organizations in the Netherlands (n=125). Results showed that employees with higher basal testosterone levels reported a more authoritarian leadership style, but this relationship was absent among those who currently held a real management position (i.e., they had at least one subordinate). Furthermore, basal testosterone levels were not different between managers and non-managers, and testosterone was not associated with various indicators of status and hierarchy such as number of subordinates, income, and position in the organizational hierarchy. In our meta-analysis (second study), we showed that basal testosterone levels were not associated with leadership in men nor in women (9 studies, n=1103). Taken together, our findings show that basal testosterone is not associated with having a leadership position in the corporate world or related to leadership styles in leaders. We suggest that basal testosterone could play a role in acquiring leadership positions through dominant and authoritarian behavior. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Potapova, O F; Potapov, M A; Kondratyuk, E Yu; Evsikov, V I
2016-05-01
In the blood of male steppe lemmings, relatively low background levels of testosterone were detected, this is characteristic of a monogamous species. A significant increase in testosterone level, more expressed in sexually active males, was observed at the initial stage of formation of reproductive couples. Apparently, in the future, the couple will exist in a stable relationship, and, hence, the maintenance of a high testosterone level becomes excessive. The decrease in, and the relative "normalization" of, the hormone level during the existence of the pair, including raising of the young, promotes higher expression of the male paternal care of the offspring at the species level.
Correlation between benzene and testosterone in workers exposed to urban pollution.
Rosati, M V; Sancini, A; Tomei, F; Sacco, C; Traversini, V; De Vita, A; De Cesare, D P; Giammichele, G; De Marco, F; Pagliara, F; Massoni, F; Ricci, L; Tomei, G; Ricci, S
2017-01-01
Many studies have examined the effects of benzene on testosterone. The purpose of this study was to evaluate the possible correlation between the blood levels of benzene and the levels of testosterone. The study involved a group of 148 subjects. For every worker have been made out a blood sample for the evaluation of benzene and testosterone levels and an urine analysis for the evaluation of the levels of trans, trans-muconic acid and S-phenylmercapturic acid. We estimated the Pearson correlation coefficient between the variables in the sample and the urinary metabolites, age, length of service, gender, BMI. For the analysis of the major confounding factors it was performed a multiple linear regression. The Pearson correlation coefficiet showed: 1. a significant inverse correlation between the S-phenyl mercapturic acid and free testosterone; 2. a significant direct correlation between trans-trans muconic acid and BMI. After dividing the sample according to the median of blood benzene (161.0 ng / L), Pearson correlation coefficient showed a significant inverse correlation between the S-phenyl mercapturic acid and free testosterone in the group with values below this median. Our results, to be considered preliminary, suggest that occupational exposure to low levels of benzene, present in urban pollution, affect the blood levels of testosterone. These results need to be confirmed in future studies, with the eventual possibility of including more specific fertility tests.
Sexual Function and Testosterone Level in Men With Conservatively Treated Chronic Kidney Disease.
Fugl-Meyer, Kerstin S; Nilsson, Marie; Hylander, Britta; Lehtihet, Mikael
2017-07-01
Sexual dysfunctions are common, but underrecognized, in patients with chronic kidney disease (CKD) and are inversely associated with the glomerular filtration rate (GFR). Sexual dysfunctions may affect quality of life in males with CKD. The aim of this study was to analyze the relationship among sex hormones, sexual function, and sexual satisfaction in a group of men between 18 and 50 years of age with CKD Stages 1 to 5 not treated with hemodialysis or peritoneal dialysis. Fasting blood samples for hemoglobin, testosterone, prolactin, and luteinizing hormone and questionnaire surveys (Sexual Complaints Screener for Men, International Index of Erectile Function, and Aging Male Symptom scale) were evaluated in 100consecutive men. Higher CKD stage (i.e., lower renal function) had a statistically significant ( p < .01) correlation with lower total testosterone, free testosterone, and hemoglobin levels, and higher luteinizing hormone and prolactin levels. Sexual function/dysfunctions were not significantly associated with CKD stage, even after adjustment for age and serum testosterone. The results indicate that CKD stage is a factor affecting testosterone levels in combination with age in men between 18 and 50 years of age at different stages of CKD but not treated with hemodialysis or peritoneal dialysis. Sexual dysfunctions are common but not strongly correlated to testosterone levels, prolactin levels, and survey (Sexual Complaints Screener for Men, International Index of Erectile Function, and Aging Male Symptom scale) responses in patients with CKD.
Testosterone Attenuates Group 2 Innate Lymphoid Cell-Mediated Airway Inflammation.
Cephus, Jacqueline-Yvonne; Stier, Matthew T; Fuseini, Hubaida; Yung, Jeffrey A; Toki, Shinji; Bloodworth, Melissa H; Zhou, Weisong; Goleniewska, Kasia; Zhang, Jian; Garon, Sarah L; Hamilton, Robert G; Poloshukin, Vasiliy V; Boyd, Kelli L; Peebles, R Stokes; Newcomb, Dawn C
2017-11-28
Sex hormones regulate many autoimmune and inflammatory diseases, including asthma. As adults, asthma prevalence is 2-fold greater in women compared to men. The number of group 2 innate lymphoid cells (ILC2) is increased in patients with asthma, and we investigate how testosterone attenuates ILC2 function. In patients with moderate to severe asthma, we determine that women have an increased number of circulating ILC2 compared to men. ILC2 from adult female mice have increased IL-2-mediated ILC2 proliferation versus ILC2 from adult male mice, as well as pre-pubescent females and males. Further, 5α-dihydrotestosterone, a hormone downstream of testosterone, decreases lung ILC2 numbers and IL-5 and IL-13 expression from ILC2. In vivo, testosterone attenuated Alternaria-extract-induced IL-5+ and IL-13+ ILC2 numbers and lung eosinophils by intrinsically decreasing lung ILC2 numbers, as well as by decreasing expression of IL-33 and thymic stromal lymphopoietin (TSLP), ILC2-stimulating cytokines. Collectively, these findings provide a foundational understanding of sexual dimorphism in ILC2 function. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Effect of anticonvulsants on plasma testosterone and sex hormone binding globulin levels.
Barragry, J M; Makin, H L; Trafford, D J; Scott, D F
1978-01-01
Plasma sex hormone binding globulin (SHBG) and testosterone levels were measured in 29 patients with epilepsy (16 men and 13 women), most of them on chronic therapy with anticonvulsant drugs. Sex hormone binding globulin concentrations were increased in both sexes and testosterone levels in male patients. It is postulated that anticonvulsants may induce hepatic synthesis of SHBG. PMID:569688
Mangolim, Amanda S; Brito, Leonardo A R; Nunes-Nogueira, Vania S
2018-04-01
The use of testosterone replacement therapy in obese men with low testosterone levels has been controversial. This review aims to analyze the effectiveness of testosterone therapy for weight loss and preventing cardiovascular complications in obese men with low testosterone levels. We will perform a systematic review according to Cochrane Methodology of randomized studies, including crossover studies, wherein patients are allocated into one of the two groups: testosterone therapy and control (no treatment or placebo). The primary outcomes analyzed will be: weight loss, adverse events, quality of life, improvement of libido, control of obesity complications, frequency of cardiovascular events, and deaths. Four general and adaptive search strategies have been created for the following electronic health databases: Embase, Medline, LILACS, and CENTRAL. Two reviewers will independently select the eligible studies, assess the risk of bias, and extract the data from included studies. Similar outcomes measured in at least two trials will be plotted in the meta-analysis using Review Manager 5.3. The quality of evidence of the effect estimate of the intervention for the outcomes that could be plotted in the meta-analysis will be generated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group. Although testosterone replacement seems to be an attractive treatment modality for obese men with low testosterone, its potential benefits has been refuted by some studies, whose results have not shown significant differences between treated and untreated patients. For obese men with low testosterone concentrations, the proposed systematic review aims to answer the following questions: When compared with no treatment or placebo: Is testosterone therapy safe? Is testosterone therapy effective in promoting weight loss, a sustained reduction in body weight and changes in body composition? Is testosterone effective in improving quality of life, libido, and erectile function? Is testosterone therapy effective in controlling obesity complications and in preventing cardiovascular events?
Wang, Kai; Chen, Xinguang; Bird, Victoria Y; Gerke, Travis A; Manini, Todd M; Prosperi, Mattia
2017-11-01
The relationship between serum total testosterone and prostate cancer (PCa) risk is controversial. The hypothesis that faster age-related reduction in testosterone is linked with increased PCa risk remains untested. We conducted our study at a tertiary-level hospital in southeast of the USA, and derived data from the Medical Registry Database of individuals that were diagnosed of any prostate-related disease from 2001 to 2015. Cases were those diagnosed of PCa and had one or more measurements of testosterone prior to PCa diagnosis. Controls were those without PCa and had one or more testosterone measurements. Multivariable logistic regression models for PCa risk of absolute levels (one-time measure and 5-year average) and annual change in testosterone were respectively constructed. Among a total of 1,559 patients, 217 were PCa cases, and neither one-time measure nor 5-year average of testosterone was found to be significantly associated with PCa risk. Among the 379 patients with two or more testosterone measurements, 27 were PCa cases. For every 10 ng/dL increment in annual reduction of testosterone, the risk of PCa would increase by 14% [adjusted odds ratio, 1.14; 95% confidence interval (CI), 1.03-1.25]. Compared to patients with a relatively stable testosterone, patients with an annual testosterone reduction of more than 30 ng/dL had 5.03 [95% CI: 1.53, 16.55] fold increase in PCa risk. This implies a faster age-related reduction in, but not absolute level of serum total testosterone as a risk factor for PCa. Further longitudinal studies are needed to confirm this finding. © 2017 UICC.
Williams, Marlene S; Cushman, Mary; Ouyang, Pamela; Heckbert, Susan R; Kalyani, Rita Rastogi; Vaidya, Dhanajay
2016-02-01
Hormone therapy (HT) is associated with increased risk of both venous and arterial thrombosis, which are multifactorial in origin. Our objectives were twofold: first, we sought to examine associations between endogenous serum sex hormone levels and biomarkers of thrombosis and/or coagulation in postmenopausal hormone nonusers. Second, we separately studied the associations between serum sex hormone levels and biomarkers of thrombosis and/or coagulation in postmenopausal hormone users considering the fact that pattern of circulating hormones is different in women taking exogenous hormones. We performed a cross-sectional analysis of postmenopausal women enrolled in a large multiethnic community-based cohort study, The Multiethnic Study of Atherosclerosis. We hypothesized that higher levels of estrogen-related sex hormones would be associated with biomarkers of thrombosis, suggesting mechanisms for differences in thrombotic risk from HT. Women (n = 2878) were included if they were postmenopausal and had thrombotic biomarkers (homocysteine, fibrinogen, C-reactive protein [CRP], factor VIII, and d-dimer) and sex hormone levels (total testosterone [T], bioavailable testosterone, sex hormone binding globulin [SHBG], estradiol [E2], and dehydroepiandrosterone [DHEA]) measured. A smaller random sample of 491 women also had von Willebrand factor (vWF), plasminogen activator inhibitor (PAI-1), and tissue factor pathway inhibitor (TFPI) levels measured. We found that elevated levels of estradiol and SHBG in HT users were associated with elevated levels of CRP and lower levels of TFPI, both of which may be related to a prothrombotic milieu in HT users. HT nonusers had far more prothrombotic associations between elevated serum sex hormone levels and thrombotic biomarkers when compared with HT users.
Gonadal Status and physical performance in older men
Maggio, Marcello; Ceda, Gian Paolo; Lauretani, Fulvio; Bandinelli, Stefania; Metter, E. Jeffrey; Guralnik, Jack M.; Basaria, Shehzad; Cattabiani, Chiara; Luci, Michele; Dall'Aglio, Elisabetta; Vignali, Alessandro; Volpi, Riccardo; Valenti, Giorgio; Ferrucci, Luigi
2011-01-01
Background Male aging is characterized by a progressive decline in serum testosterone levels and physical performance. Low testosterone levels may be implicated in the decline of physical performance and consequent mobility disability that occurs with aging. During the recent years many consensus reports have advocated that one of the potential effects of testosterone supplementation is the improvement in mobility. However, to the best of our knowledge no study has fully investigated the relationship between gonadal status and objective measures of physical performance in older men and their determinants. Methods We evaluated 455 ≥ 65 year old male participants of InCHIANTI study a population based study in two municipalities of Tuscany, Italy with complete data on testosterone levels, hand grip strength, cross-sectional muscle area (CSMA), short physical performance battery (SPPB). Linear models were used to test the relationship between gonadal status and determinants of physical performance. Results According to baseline serum levels of total testosterone, three different groups of older men were created: 1) severely hypogonadal (N= 23),total testosterone levels ≤230 ng /dl; 2) moderately hypogonadal (N=88), total testosterone >230 and <350 ng/dL), and 3) eugonadal (N=344), testosterone levels ≥350 ng/dL. With increased severity of hypogonadal status, participants were significantly older while their BMI was substantially similar. In the age and BMI adjusted analysis, there was a significant difference in hemoglobin levels, hand grip strength and SPPB score (p for trend<0.001) among −3 groups, with severely hypogonadal men having lower values of hemoglobin, muscle strength and physical performance. We found no association between testosterone group assignment and calf muscle mass and 4 meter walking speed. In the multivariate analysis grip strength (p for trend=0.004) and haemoglobin (p for trend <0.0001) but not SPPB and other determinants of physical performance were significantly different between the 3 groups. Conclusions In older men, gonadal status is independently associated with some determinants (hemoglobin and muscle strength) of physical performance. PMID:20937007
Lowered testosterone in male obesity: mechanisms, morbidity and management
Fui, Mark Ng Tang; Dupuis, Philippe; Grossmann, Mathis
2014-01-01
With increasing modernization and urbanization of Asia, much of the future focus of the obesity epidemic will be in the Asian region. Low testosterone levels are frequently encountered in obese men who do not otherwise have a recognizable hypothalamic-pituitary-testicular (HPT) axis pathology. Moderate obesity predominantly decreases total testosterone due to insulin resistance-associated reductions in sex hormone binding globulin. More severe obesity is additionally associated with reductions in free testosterone levels due to suppression of the HPT axis. Low testosterone by itself leads to increasing adiposity, creating a self-perpetuating cycle of metabolic complications. Obesity-associated hypotestosteronemia is a functional, non-permanent state, which can be reversible, but this requires substantial weight loss. While testosterone treatment can lead to moderate reductions in fat mass, obesity by itself, in the absence of symptomatic androgen deficiency, is not an established indication for testosterone therapy. Testosterone therapy may lead to a worsening of untreated sleep apnea and compromise fertility. Whether testosterone therapy augments diet- and exercise-induced weight loss requires evaluation in adequately designed randomized controlled clinical trials. PMID:24407187
Lipophagy Contributes to Testosterone Biosynthesis in Male Rat Leydig Cells.
Ma, Yi; Zhou, Yan; Zhu, Yin-Ci; Wang, Si-Qi; Ping, Ping; Chen, Xiang-Feng
2018-02-01
In recent years, autophagy was found to regulate lipid metabolism through a process termed lipophagy. Lipophagy modulates the degradation of cholesteryl esters to free cholesterol (FC), which is the substrate of testosterone biosynthesis. However, the role of lipophagy in testosterone production is unknown. To investigate this, primary rat Leydig cells and varicocele rat models were administered to inhibit or promote autophagy, and testosterone, lipid droplets (LDs), total cholesterol (TC), and FC were evaluated. The results demonstrated that inhibiting autophagy in primary rat Leydig cells reduced testosterone production. Further studies demonstrated that inhibiting autophagy increased the number and size of LDs and the level of TC, but decreased the level of FC. Furthermore, hypoxia promoted autophagy in Leydig cells. We found that short-term hypoxia stimulated testosterone secretion; however, the inhibition of autophagy abolished stimulated testosterone release. Hypoxia decreased the number and size of LDs in Leydig cells, but the changes could be largely rescued by blocking autophagy. In experimental varicocele rat models, the administration of autophagy inhibitors substantially reduced serum testosterone. These data demonstrate that autophagy contributes to testosterone biosynthesis at least partially through degrading intracellular LDs/TC. Our observations might reveal an autophagic regulatory mode regarding testosterone biosynthesis. Copyright © 2018 Endocrine Society.
Androgen Supplementation During Aging: Development of a Physiologically Appropriate Protocol
Sorwell, Krystina G.; Garyfallou, Vasilios T.; Garten, Jamie; Weiss, Alison; Renner, Laurie; Neuringer, Martha; Kohama, Steven G.
2014-01-01
Abstract Men show an age-related decline in the circulating levels of testosterone (T) and dehydroepiandrosterone sulfate (DHEAS). Consequently, there is interest in developing androgen supplementation paradigms for old men that replicate the hormone profiles of young adults. In the present study, we used old (21–26 years old) male rhesus monkeys as a model to examine the efficacy of an androgen supplementation paradigm that comprised oral T administration (12 mg/kg body weight, dissolved in sesame oil/chocolate) in the evening, and two oral DHEA administrations, 3 hr apart (0.04 mg/kg body weight, dissolved in sesame oil/chocolate) in the morning. After 5 days of repeated hormone supplementation, serial blood samples were remotely collected from each animal hourly across the 24-hr day, and assayed for cortisol, DHEAS, T, 5α-dihydrotestosterone (DHT), estrone (E1), and 17β-estradiol (E2). Following androgen supplementation, T levels were significantly elevated and this was associated with a more sustained nocturnal elevation of T's primary bioactive metabolites, DHT and E1 and E2. Plasma DHEAS levels were also significantly elevated after androgen supplementation; DHEAS levels rose in the early morning and gradually declined during the course of the day, closely mimicking the profiles observed in young adults (7–12 years old); in contrast, cortisol levels were unaltered by the supplementation. Together the data demonstrate a non-invasive androgen supplementation paradigm that restores youthful circulating androgen levels in old male primates. Because this paradigm preserves the natural circulating circadian hormone patterns, we predict that it will produce fewer adverse side effects, such as perturbed sleep or cognitive impairment. PMID:24134213
Zhou, Tong; Yang, Rupu; Li, Shihong; Zheng, Guoqing; Xi, Yu; Cheng, Xuemin; Hou, Jiaxiang; Cui, Liuxin; Ba, Yue
2013-03-01
To explore the influence of water fluoride exposure on sex hormone binding globulin (SHBG) and testosterone in adult male. Cross-sectional study was conducted in three villages of Tongxu county including high fluoride group (HFG), defluoridation project group (DFPG) and control group (CG) based on the fluoride concentration in drinking water. Adult male who were born and raised in the village and aged 18 - 50 years old were recruited using cluster sampling. Fasting blood and morning urine samples were collected. The fluoride levels in drinking water and urine were detected by fluoride-ion selective electrode method. Serum SHBG level was determined using enzyme-linked immunosorbent assay (ELISA). The chemical luminescence immune analysis method was used to detect serum testosterone content. Serum SHBG level was 47.85 nmol/L in CG, 31.37 nmol/L in DFPG and 24.52 nmol/L in HFG respectively. There were significant difference among of three groups (P < 0.05). Serum testosterone level was 3.69 ng/ml in CG, 4.61 ng/ml in DFPG and 4.83 ng/ml in HFG respectively. Serum testosterone level in HFG was significantly higher than that in CG (P < 0.05). Serum SHBG level in HFG has positive correlation with serum testosterone (r = 0.230, P = 0.049), which has not been observed in DFPG and CG. Long-time fluorine exposure may affect serum SHBG and testosterone level in adult male.
Bandak, Mikkel; Jørgensen, Niels; Juul, Anders; Lauritsen, Jakob; Kreiberg, Michael; Oturai, Peter Sandor; Helge, Jørn Wulff; Daugaard, Gedske
2017-07-03
Elevated serum levels of luteinizing hormone and slightly decreased serum levels of testosterone (mild Leydig cell insufficiency) is a common hormonal disturbance in testicular cancer (TC) survivors. A number of studies have shown that low serum levels of testosterone is associated with low grade inflammation and increased risk of metabolic syndrome. However, so far, no studies have evaluated whether testosterone substitution improves metabolic dysfunction in TC survivors with mild Leydig cell insufficiency. This is a single-center, randomized, double-blind, placebo-controlled study, designed to evaluate the effect of testosterone replacement therapy in TC survivors with mild Leydig cell insufficiency. Seventy subjects will be randomized to receive either testosterone replacement therapy or placebo. The subjects will be invited for an information meeting where informed consent will be obtained. Afterwards, a 52-weeks treatment period begins in which study participants will receive a daily dose of transdermal testosterone or placebo. Dose adjustment will be made three times during the initial 8 weeks of the study to a maximal daily dose of 40 mg of testosterone in the intervention arm. Evaluation of primary and secondary endpoints will be performed at baseline, 26 weeks post-randomization, at the end of treatment (52 weeks) and 3 months after completion of treatment (week 64). This study is the first to investigate the effect of testosterone substitution in testicular cancer survivors with mild Leydig cell insufficiency. If positive, it may change the clinical handling of testicular cancer survivors with borderline low levels of testosterone. ClinicalTrials.gov : NCT02991209 (November 25, 2016).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bruheim, Kjersti; Svartberg, Johan; Department of Medicine, University Hospital of North Norway, Tromso
Purpose: It is known that scattered radiation to the testes during pelvic radiotherapy can affect fertility, but there is little knowledge on its effects on male sex hormones. The aim of this study was to determine whether radiotherapy for rectal cancer affects testosterone production. Methods and Materials: All male patients who had received adjuvant radiotherapy for rectal cancer from 1993 to 2003 were identified from the Norwegian Rectal Cancer Registry. Patients treated with surgery alone were randomly selected from the same registry as control subjects. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and sex hormone bindingmore » globulin (SHBG) were analyzed, and free testosterone was calculated (N = 290). Information about the radiotherapy treatment was collected from the patient hospital charts. Results: Serum FSH was 3 times higher in the radiotherapy group than in the control group (median, 18.8 vs. 6.3 IU/L, p <0.001), and serum LH was 1.7 times higher (median, 7.5 vs. 4.5 IU/l, p <0.001). In the radiotherapy group, 27% of patients had testosterone levels below the reference range (8-35 nmol/L), compared with 10% of the nonirradiated patients (p <0.001). Irradiated patients had lower serum testosterone (mean, 11.1 vs. 13.4 nmol/L, p <0.001) and lower calculated free testosterone (mean, 214 vs. 235 pmol/L, p <0.05) than control subjects. Total testosterone, calculated free testosterone, and gonadotropins were related to the distance from the bony pelvic structures to the caudal field edge. Conclusions: Increased serum levels of gonadotropins and subnormal serum levels of testosterone indicate that curative radiotherapy for rectal cancer can result in permanent testicular dysfunction.« less
Chan, Kelly J; Liang, Jennifer J; Jolly, Divya; Weinand, Jamie D; Safer, Joshua D
2018-04-06
Polycystic ovarian syndrome (PCOS) is a complex condition which can include menstrual irregularity, metabolic derangement, and increased androgen levels. The mechanism of PCOS is unknown. Some suggest that excess production of androgens by the ovaries may cause or exacerbate the metabolic findings. The purpose of this study was to assess the role of increased testosterone on metabolic parameters on individuals presumed to be chromosomally female by examination of these parameters in hormone-treated transgender men. In 2015 and 2016, we asked all transgender men who visited the Endocrinology Clinic at Boston Medical Center treated with testosterone for consent for a retrospective anonymous chart review. Of the 36 men, 34 agreed (94%). Serum metabolic factors and body mass index levels for each patient were graphed over time, from initiation of therapy through 6 years of treatment. Bivariate analyses were conducted to analyze the impact of added testosterone. Regressions measuring the impact of testosterone demonstrated no significant change in levels of glycosylated hemoglobin, triglycerides, or low density lipoprotein cholesterol. There was a statistically significant decrease in BMI with increasing testosterone. There was also a statistically significant decrease in high density lipoprotein levels upon initiation of testosterone therapy. Testosterone therapy in transgender men across a wide range of doses and over many years did not result in the abnormalities in HbA1c or dyslipidemia seen with PCOS. Instead, treatment of transgender men with testosterone resulted only in a shift of metabolic biomarkers toward the average physiologic male body. This retrospective chart review of 34 transgender men found that testosterone therapy does not induce or exacerbate the metabolic features associated with PCOS.
Goncharov, Alexey; Rej, Robert; Negoita, Serban; Schymura, Maria; Santiago-Rivera, Azara; Morse, Gayle; Carpenter, David O
2009-09-01
Polychlorinated biphenyls (PCBs) and chlorinated pesticides are endocrine disruptors, altering both thyroid and estrogen hormonal systems. Less is known of action on androgenic systems. We studied the relationship between serum concentrations of testosterone in relation to levels of PCBs and three chlorinated pesticides in an adult Native American (Mohawk) population. We collected fasting serum samples from 703 adult Mohawks (257 men and 436 women) and analyzed samples for 101 PCB congeners, hexachlorobenzene (HCB), dichlorodiphenyldichloroethylene (DDE), and mirex, as well as testosterone, cholesterol, and triglycerides. The associations between testosterone and tertiles of serum organochlorine levels (both wet weight and lipid adjusted) were assessed using a logistic regression model while controlling for age, body mass index (BMI), and other analytes, with the lowest tertile being considered the referent. Males and females were considered separately. Testosterone concentrations in males were inversely correlated with total PCB concentration, whether using wet-weight or lipid-adjusted values. The odds ratio (OR) of having a testosterone concentration above the median was 0.17 [95% confidence interval (CI), 0.05-0.69] for total wet-weight PCBs (highest vs. lowest tertile) after adjustment for age, BMI, total serum lipids, and three pesticides. The OR for lipid-adjusted total PCB concentration was 0.23 (95% CI, 0.06-0.78) after adjustment for other analytes. Testosterone levels were significantly and inversely related to concentrations of PCBs 74, 99, 153, and 206, but not PCBs 52, 105, 118, 138, 170, 180, 201, or 203. Testosterone concentrations in females are much lower than in males, and not significantly related to serum PCBs. HCB, DDE, and mirex were not associated with testosterone concentration in either men or women. Elevation in serum PCB levels is associated with a lower concentration of serum testosterone in Native American men.
Low bioavailable testosterone levels predict future height loss in postmenopausal women.
Jassal, S K; Barrett-Connor, E; Edelstein, S L
1995-04-01
The objective of this study was to examine the relation of endogenous sex hormones to subsequent height loss in postmenopausal women, in whom height loss is usually a surrogate for osteoporotic vertebral fractures. This was a prospective, community-based study. The site chosen was Rancho Bernardo, an upper middle class community in Southern California. A total of 170 postmenopausal women participated, aged 55-80 years. None of them were taking exogenous estrogen between 1972 and 1974. Plasma was obtained for sex hormone and sex hormone-binding globulin (SHBG) assays. Estradiol/SHBG and testosterone/SHBG ratios were used to estimate biologically available hormone levels; bioavailable (non-SHBG-bound) testosterone was measured directly in 60 women. Height loss was based on height measurements taken 16 years apart. Height loss was strongly correlated with age (p = 0.001). These women lost an average 0.22 cm/year in height. Neither estrone nor estradiol levels were significantly and independently related to height loss. Both estimated bioavailable testosterone (testosterone/SHBG ratio) and measured bioavailable testosterone levels predicted future height loss (p = 0.02 and 0.08, respectively) independent of age, obesity, cigarette smoking, alcohol intake, and use of thiazides and estrogen. We conclude that bioavailable testosterone is an independent predictor of height loss in elderly postmenopausal women. The reduced height loss is compatible with a direct effect of testosterone on bone mineral density or bone remodeling.
Eisenegger, Christoph; Kumsta, Robert; Naef, Michael; Gromoll, Jörg; Heinrichs, Markus
2017-06-01
A contribution to a special issue on Hormones and Human Competition. Studies in non-human animals and humans have demonstrated the important role of testosterone in competitive interactions. Here, we investigated whether endogenous testosterone levels predict the decision to compete, in a design excluding spite as a motive underlying competitiveness. In a laboratory experiment with real monetary incentives, 181 men solved arithmetic problems, first under a noncompetitive piece rate, followed by a competition incentive scheme. We also assessed several parameters relevant to competition, such as risk taking, performance, and confidence in one's own performance. Salivary testosterone levels were measured before and 20min after the competition task using mass spectrometry. Participants were also genotyped for the CAG repeat polymorphism of the androgen receptor gene, known to influence the efficacy of testosterone signaling in a reciprocal relationship to the number of CAG repeats. We observed a significant positive association between basal testosterone levels and the decision to compete, and that higher testosterone levels were related to greater confidence in one's own performance. Whereas the number of CAG repeats was not associated with the choice to compete, a lower number of CAG repeats was related to greater confidence in those who chose to compete, but this effect was attributable to the polymorphism's effect on actual performance. An increase in testosterone levels was observed following the experiment, and this increase varied with self-reported high-school math grades. We expand upon the latest research by documenting effects of the androgen system in confidence in one's own ability, and conclude that testosterone promotes competitiveness without spite. Copyright © 2016 Elsevier Inc. All rights reserved.
Boeri, Luca; Capogrosso, Paolo; Ventimiglia, Eugenio; Cazzaniga, Walter; Pederzoli, Filippo; Moretti, Donatella; Dehò, Federico; Montanari, Emanuele; Montorsi, Francesco; Salonia, Andrea
2017-12-01
Although erectile dysfunction (ED) has been associated with low circulating total testosterone (TT) levels, the utility of free testosterone (FT) over TT is debatable. To assess the relative impact of low TT and low calculated FT (cFT) on androgen-related sexual symptoms in men with ED. Data from 485 men were analyzed. Comorbidities were scored with the Charlson Comorbidity Index (CCI). Patients completed the International Index of Erectile Function (IIEF) and the Beck Inventory for Depression (BDI). Descriptive statistics tested differences between patients with normal TT levels (>3 ng/mL) and normal cFT levels (>65 pg/mL; group 1) and men with normal TT and low cFT (group 2), low TT and normal cFT (group 3), and low TT and low cFT (group 4). Linear regression models tested the association between clinical predictors and sexual function impairment. We assessed the impact of different hormonal categories on androgen-related symptoms and the clinical utility of measuring cFT in men with ED. Groups 1, 2, 3, and 4 were composed of 338 (69.6%), 44 (9.1%), 34 (7.0%), and 69 (14.3%) patients, respectively. Compared with group 1, patients in group 2 were older (P < .001), had a higher body mass index (P < .01), and had a larger proportion with CCI scores of at least 1 (P = .006). Likewise, group 2 presented lower scores for the IIEF erectile function (P = .07), sexual desire (P = .04), and orgasmic function (P = .007) domains and lower BDI scores (P = .02) than group 1. Similar findings were found for group 4 vs 1. Conversely, patients in group 3 had similar scores on the questionnaires to those in group 1. Low cFT and normal or low TT achieved independent predictor status for pathologic IIEF domains and BDI scores after accounting for age, CCI, and body mass index. Conversely, low TT and normal cFT status was not associated with pathologic scores on the questionnaires. The inclusion of cFT in the first-line assessment of hypogonadal symptoms in men with ED has major clinical utility. This is the first study evaluating the concomitant impact of TT and cFT on men with ED using well-validated instruments to assess patients' sexuality and depressive symptoms. Limitations are the retrospective nature of the study and lack of physical function data and bone ultrasound measurements. Although normal cFT was not associated with signs and symptoms suggestive of testosterone deficiency, even when concomitant with low TT or low cFT irrespective of TT values, it was indicative of poorer clinical profiles and impaired sexual and depressive parameters compared with normal TT and normal cFT in a cohort of patients with ED. Boeri L, Capogrosso P, Ventimiglia E, et al. Does Calculated Free Testosterone Overcome Total Testosterone in Protecting From Sexual Symptom Impairment? Findings of a Cross-Sectional Study. J Sex Med 2017;14:1549-1557. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Testosterone and cardiovascular disease in men
Morris, Paul D; Channer, Kevin S
2012-01-01
Despite regional variations in the prevalence of coronary artery disease (CAD), men are consistently more at risk of developing and dying from CAD than women, and the gender-specific effects of sex hormones are implicated in this inequality. This ‘Perspectives' article reviews the current evidence regarding the cardiovascular effects of testosterone in men including an examination of the age-related decline in testosterone, the relationship between testosterone levels and coronary disease, coronary risk factors and mortality. We also review the vaso-active effects of testosterone, and discuss how these have been used in men with heart failure and angina. We discuss the ‘cause' versus ‘effect' controversy, regarding low testosterone levels in men with coronary heart disease, as well as concerns over the use of testosterone replacement therapy in middle aged and elderly men. The article concludes with a discussion regarding the future direction for work in this interesting area, including the relative merits of screening for, and treating hypogonadism with testosterone replacement therapy in men with heart disease. PMID:22522504
Zhao, Di; Ouyang, Pamela; de Boer, Ian H; Lutsey, Pamela L; Farag, Youssef M K; Guallar, Eliseo; Siscovick, David S; Post, Wendy S; Kalyani, Rita R; Billups, Kevin L; Michos, Erin D
2017-02-01
25-hydroxyvitamin D [25(OH)D] deficiency has been associated with low testosterone levels in men, but there are conflicting reports of its associations with sex hormones in women. Less is known about whether these associations are independent of adiposity and lifestyle factors, and whether they differ by race/ethnicity. To examine associations of 25(OH)D concentrations with sex hormone levels. Cross-sectional analysis of 3017 men and 2929 women in a multi-ethnic cohort. Testosterone, estradiol, dehydroepiandrosterone (DHEA), sex hormone binding globulin (SHBG), and free testosterone. The mean (SD) levels of 25(OH)D in men and women were 25.7(10.4) and 26.1(12.0)ng/ml, respectively. In men, after adjusting for demographic and lifestyle variables, a 10ng/ml [25nmol/L] decrease in 25(OH)D was associated with an average difference of -0.70nmol/L (95%CI -1.36, -0.05) in SHBG and 0.02 percent (0.01, 0.04) in free testosterone, but was not associated with low total testosterone level (<10.41nmol/L). In women, a 10ng/ml decrease in 25(OH)D levels was associated with an average difference of -0.01nmol/L (-0.01, -0.00) for estradiol, -8.29nmol/L (-10.13, -6.45) for SHBG, 0.06 percent (0.04, 0.07) for free testosterone, and 0.40nmol/L (0.19, 0.62) for DHEA. There was no significant interaction by race/ethnicity. Lower 25(OH)D concentrations were associated with lower SHBG levels and higher free testosterone levels in both men and women, and lower estradiol and higher DHEA levels in women, independent of adiposity and lifestyle. We observed no significant association of 25(OH)D with total testosterone in men. Future studies are needed to determine whether vitamin D supplementation influences sex hormone levels. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
The effects of saliva collection, handling and storage on salivary testosterone measurement.
Durdiaková, Jaroslava; Fábryová, Helena; Koborová, Ivana; Ostatníková, Daniela; Celec, Peter
2013-12-20
Several endocrine parameters commonly measured in plasma, such as steroid hormones, can be measured in the oral fluid. However, there are several technical aspects of saliva sampling and processing that can potentially bias the validity of salivary testosterone measurement. The aim of this study was to evaluate the effects caused by repeated sampling; 5 min centrifugation (at 2000, 6000 or 10,000g); the stimulation of saliva flow by a cotton swab soaked in 2% citric acid touching the tongue; different storage times and conditions as well as the impact of blood contamination on salivary testosterone concentration measured using a commercially available ELISA kit. Fresh, unprocessed, unstimulated saliva samples served as a control. Salivary testosterone concentrations were influenced neither by repeated sampling nor by stimulation of salivary flow. Testosterone levels determined in samples stored in various laboratory conditions for time periods up to 1 month did not differ in comparison with controls. For both genders, salivary testosterone levels were substantially reduced after centrifugation (men F=29.1; women F=56.17, p<0.0001). Blood contamination decreased salivary testosterone levels in a dose-dependent manner (men F=6.54, p<0.01, F=5.01, p<0.05). Salivary testosterone can be considered A robust and stable marker. However, saliva processing and blood leakage can introduce bias into measurements of salivary testosterone using ELISA. Our observations should be considered in studies focusing on salivary testosterone. Copyright © 2013 Elsevier Inc. All rights reserved.
The female menstrual cycle does not influence testosterone concentrations in male partners.
Strom, Jakob O; Ingberg, Edvin; Druvefors, Emma; Theodorsson, Annette; Theodorsson, Elvar
2012-01-03
The time of ovulation has since long been believed to be concealed to male heterosexual partners. Recent studies have, however, called for revision of this notion. For example, male testosterone concentrations have been shown to increase in response to olfactory ovulation cues, which could be biologically relevant by increasing sexual drive and aggressiveness. However, this phenomenon has not previously been investigated in real-life human settings. We therefore thought it of interest to test the hypothesis that males' salivary testosterone concentrations are influenced by phases of their female partners' menstrual cycle; expecting a testosterone peak at ovulation. Thirty young, healthy, heterosexual couples were recruited. During the course of 30-40 days, the women registered menses and ovulation, while the men registered sexual activity, physical exercise, alcohol intake and illness (confounders), and obtained daily saliva samples for testosterone measurements. All data, including the registered confounders, were subjected to multiple regression analysis. In contrast to the hypothesis, the ovulation did not affect the testosterone levels, and the resulting testosterone profile during the menstrual cycle was on the average flat. The specific main hypothesis, that male testosterone levels on the day of ovulation would be higher than day 4 of the cycle, was clearly contradicted by a type II error(β)-analysis (< 14.3% difference in normalized testosterone concentration; β = 0.05). Even though an ovulation-related salivary testosterone peak was observed in individual cases, no significant effect was found on a group level.
The female menstrual cycle does not influence testosterone concentrations in male partners
2012-01-01
Background The time of ovulation has since long been believed to be concealed to male heterosexual partners. Recent studies have, however, called for revision of this notion. For example, male testosterone concentrations have been shown to increase in response to olfactory ovulation cues, which could be biologically relevant by increasing sexual drive and aggressiveness. However, this phenomenon has not previously been investigated in real-life human settings. We therefore thought it of interest to test the hypothesis that males' salivary testosterone concentrations are influenced by phases of their female partners' menstrual cycle; expecting a testosterone peak at ovulation. Methods Thirty young, healthy, heterosexual couples were recruited. During the course of 30-40 days, the women registered menses and ovulation, while the men registered sexual activity, physical exercise, alcohol intake and illness (confounders), and obtained daily saliva samples for testosterone measurements. All data, including the registered confounders, were subjected to multiple regression analysis. Results In contrast to the hypothesis, the ovulation did not affect the testosterone levels, and the resulting testosterone profile during the menstrual cycle was on the average flat. The specific main hypothesis, that male testosterone levels on the day of ovulation would be higher than day 4 of the cycle, was clearly contradicted by a type II error(β)-analysis (< 14.3% difference in normalized testosterone concentration; β = 0.05). Conclusions Even though an ovulation-related salivary testosterone peak was observed in individual cases, no significant effect was found on a group level. PMID:22214343
Zhou, Xin; Wei, Yuan; Xie, Fang; Laukaitis, Christina M.; Karn, Robert C.; Kluetzman, Kerri; Gu, Jun; Zhang, Qing-Yu; Roberts, Dean W.
2011-01-01
To identify novel factors or mechanisms that are important for the resistance of tissues to chemical toxicity, we have determined the mechanisms underlying the previously observed increases in resistance to acetaminophen (APAP) toxicity in the lateral nasal gland (LNG) of the male Cyp2g1-null/Cyp2a5-low mouse. Initial studies established that Cyp2a5-null mice, but not a newly generated strain of Cyp2g1-null mice, were resistant to APAP toxicity in the LNG; therefore, subsequent studies were focused on the Cyp2a5-null mice. Compared with the wild-type (WT) male mouse, the Cyp2a5-null male mouse had intact capability to metabolize APAP to reactive intermediates in the LNG, as well as unaltered circulating levels of APAP, APAP-GSH, APAP-glucuronide, and APAP-sulfate. However, it displayed reduced tissue levels of APAP and APAP-GSH and increased tissue levels of testosterone and salivary androgen-binding protein (ABP) in the LNG. Furthermore, we found that ABP was able to compete with GSH and cellular proteins for adduction with reactive metabolites of APAP in vitro. The amounts of APAP-ABP adducts formed in vivo were greater, whereas the amounts of APAP adducts formed with other cellular proteins were substantially lower, in the LNG of APAP-treated male Cyp2a5-null mice compared with the LNG of APAP-treated male WT mice. We propose that through its critical role in testosterone metabolism, CYP2A5 regulates 1) the bioavailability of APAP and APAP-GSH (presumably through modulation of the rates of xenobiotic excretion from the LNG) and 2) the expression of ABP, which can quench reactive APAP metabolites and thereby spare critical cellular proteins from inactivation. PMID:21252290
DOE Office of Scientific and Technical Information (OSTI.GOV)
Qin, Weiping, E-mail: weiping.qin@mssm.edu; Department of Medicine, Mount Sinai School of Medicine, NY; Pan, Jiangping
Research highlights: {yields} In rat gastrocnemius muscle, dexamethasone reduced PGC-1{alpha} cellular and nuclear levels without altering mRNA levels for this factor. {yields} Dexamethasone reduced phosphorylating of p38 MAPK, which stabilizes PGC-1{alpha} and promotes its nuclear entry. {yields} Co-administration of testosterone with dexamethasone increased cellular and nuclear levels of PGC-1{alpha} protein without changing its mRNA levels. {yields} Co-administration of testosterone restored p38 MAPK levels to those of controls. -- Abstract: Glucocorticoid-induced muscle atrophy results from muscle protein catabolism and reduced protein synthesis, associated with increased expression of two muscle-specific ubiquitin ligases (MAFbx and MuRF1), and of two inhibitors of protein synthesis,more » REDD1 and 4EBP1. MAFbx, MuRF1, REDD1 and 4EBP1 are up-regulated by the transcription factors FOXO1 and FOXO3A. The transcriptional co-activator PGC-1{alpha} has been shown to attenuate many forms of muscle atrophy and to repress FOXO3A-mediated transcription of atrophy-specific genes. Dexamethasone-induced muscle atrophy can be prevented by testosterone, which blocks up-regulation by dexamethasone of FOXO1. Here, an animal model of dexamethasone-induced muscle atrophy was used to further characterize effects of testosterone to abrogate adverse actions of dexamethasone on FOXO1 levels and nuclear localization, and to determine how these agents affect PGC-1{alpha}, and its upstream activators, p38 MAPK and AMPK. In rat gastrocnemius muscle, testosterone blunted the dexamethasone-mediated increase in levels of FOXO1 mRNA, and FOXO1 total and nuclear protein. Dexamethasone reduced total and nuclear PGC-1{alpha} protein levels in the gastrocnemius; co-administration of testosterone with dexamethasone increased total and nuclear PGC-1{alpha} levels above those present in untreated controls. Testosterone blocked dexamethasone-induced decreases in activity of p38 MAPK in the gastrocnemius muscle. Regulation of FOXO1, PGC-1{alpha} and p38 MAPK by testosterone may represent a novel mechanism by which this agent protects against dexamethasone-induced muscle atrophy.« less
Stahlman, Jodi; Britto, Margaret; Fitzpatrick, Sherahe; McWhirter, Cecilia; Testino, Samuel A; Brennan, John J; Zumbrunnen, Troy L
2012-02-01
To evaluate secondary exposure of testosterone transferred to females from a male partner, dosed with 1.62% testosterone gel after direct skin-to-skin contact with the application site, and to investigate the effect of wearing a t-shirt on testosterone transfer. Across three studies, a total of 72 healthy males applied 5.0 g 1.62% testosterone gel to their abdomen alone, upper arms/shoulders alone, or a combination of their upper arms/shoulders and abdomen (single dose or once daily for 7 days). Male-female contact occurred 2 or 12 hours after testosterone gel application, with males either wearing or not wearing a t-shirt. There were 15 minutes of supervised contact with the application site between the male and his female partner. Blood samples were collected over a 24 hour period in females for assessment of serum testosterone levels at baseline and after contact. Pharmacokinetic parameters included C(max) (maximum serum concentration), AUC(0-24) (area under the serum concentration-time curve from 0-24 hours), and C(av) (time-averaged concentration over the 24-hour period post-contact). Subjects were monitored for adverse events. CLINICAL TRIAL REGISTRATION NCT NUMBERS: Study 1 was not registered (first subject enrolled 8 March 2007); Study 2: 00998933; Study 3, 01130298. Testosterone levels (C(av) and C(max)) in females increased 86-185% from baseline after direct abdominal skin contact, although C(av) levels remained within female eugonadal range. Testosterone concentrations returned to baseline within 48 hours after last skin contact. A t-shirt barrier reduced testosterone transfer by approximately 40-48% when 5.0 g of testosterone gel was applied to the abdomen alone. A t-shirt barrier prevented transfer when 5.0 g of testosterone gel was applied to the upper arms and shoulders or to a combination of the upper arms and shoulders and the abdomen (C(max) and C(av) increased by approximately 5-11%). No major safety events were observed during the studies. There is a risk of testosterone transfer from males using 1.62% testosterone gel to others who come in contact with the application site for at least 12 hours after application. Secondary exposure can be mitigated by means of a t-shirt barrier. Women for these studies were not selected by menopausal status. The study designs were intended to simulate exaggerated conditions of transfer.
Testosterone concentrations in female athletes and ballet dancers with menstrual disorders.
Łagowska, Karolina; Kapczuk, Karina
2016-01-01
Menstrual disorders are common among female athletes and ballet dancers. Endocrine changes, such as high testosterone (HT) levels and high luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratios, may suggest functional ovarian hyperandrogenism which may induce such dysfunction. The aim of this study was therefore to evaluate endocrine status in female athletes and ballet dancers with menstrual disorders. Their nutritional status and dietary habits were analysed in relation to the testosterone levels. In a cross-sectional approach, 31 female athletes (18.1 ± 2.6 years) and 21 ballerinas (17.1 ± 0.9) with menstrual disorders participated in the study. The levels of serum LH, FSH, progesterone (P), estradiol (E2), prolactin (PRL), thyroid-stimulating hormone, testosterone (T) and sex hormone-binding globulinwere measured to assess hormonal status. In addition, the free androgen index (FAI) was calculated. Nutritional status, total daily energy expenditure and nutritional habits were evaluated. Girls were assigned to one of the following groups: low testosterone (LT) level, normal testosterone level or HT level. There were significant differences between ballerinas and other female athletes in terms of testosterone levels, FAI, age at the beginning of training, length of training period and age at menarche. The PRL level was lowest in the LT group while the FAI index was highest in the HT group. Daily energy and carbohydrate intakes were significantly lower in the HT group. T levels in the study subjects were found to be associated with nutritional factors, energy availability, age at the beginning of training and frequency of training. This is the first report of HT levels being associated with the status of a female ballet dancer, the age of menarche and the length of the training history. Further research is necessary to confirm the results in a larger study group.
Gustafsson, O; Norming, U; Gustafsson, S; Eneroth, P; Aström, G; Nyman, C R
1996-03-01
To investigate the possible relationship between serum levels of prostate specific antigen (PSA), dihydrotestosterone (DHT), testosterone, sexual-hormone binding globulin (SHBG) and tumour stage, grade and ploidy in 65 cases of prostate cancer diagnosed in a screening study compared to 130 controls from the same population. From a population of 26,602 men between the ages of 55 and 70 years, 2400 were selected randomly and invited to undergo screening for prostate cancer using a digital rectal examination, transrectal ultrasonography and PSA analysis. Among the 1782 attendees, 65 cases of prostate cancer were diagnosed. Each case was matched with two control subjects of similar age and prostate volume from the screening population. Frozen serum samples were analysed for PSA, DHT, testosterone and SHBG, and compared to the diagnosis and tumour stage, grade and ploidy. Comparisons between these variables, and multivariate and regression analyses were performed. There were significant differences in PSA level with all variables except tumour ploidy. DHT levels were slightly lower in patients with prostate cancer but the difference was not statistically significant. There was a trend towards lower DHT values in more advanced tumours and the difference for T-stages was close to statistical significance (P = 0.059). Testosterone levels were lower in patients with cancer than in the control group, but the differences were not significant. There was no correlation between testosterone levels, tumour stage and ploidy, but the differences in testosterone level in tumours of a low grade of differentiation compared to those with intermediate and high grade was nearly significant (P = 0.058). The testosterone/DHT ratio tended to be higher in patients with more advanced tumours. SHBG levels were lower in patients with cancer than in controls but the differences were not statistically significant. There were no systematic variations of tumour stage, grade and ploidy. Multivariate analysis showed that if the PSA level was known, then DHT, testosterone or SHBG added no further information concerning diagnosis, stage, grade or ploidy. Regression analysis on T-stage, PSA level and DHT showed an inverse linear relationship between PSA and DHT for stage T-3 (P = 0.035), but there was no relationship between PSA and testosterone. PSA was of value in discriminating between cases and controls and between various tumour stages and grades, but no statistically significant correlation was found for ploidy. If PSA level was known, no other variable added information in individual cases. Within a group, DHT levels tended to be lower among cases and in those with more advanced tumours. There was an inverse relationship between tumour volume, as defined by PSA level, and 5 alpha-reductase activity, as defined by DHT level, and the testosterone/DHT ratio. This trend was most obvious with T-stage. No systematic variation were found in the levels of testosterone or SHBG.
Comas, I; Ferrer, R; Planas, J; Celma, A; Regis, L; Morote, J
2018-03-01
The clinical practice guidelines recommend measuring serum testosterone in patients with prostate cancer (PC) who undergo castration. The serum testosterone concentration should be <50ng/dL, a level established by using a radioimmunoassay method. The use of chemiluminescent immunoassays (IA) has become widespread, although their metrological characteristics do not seem appropriate for quantifying low testosterone concentrations. The objective of this review is to analyse the methods for quantifying testosterone and to establish whether there is scientific evidence that justifies measuring it in patients with PC who undergo castration, through liquid chromatography attached to a mass spectrometry in tandem (LC-MSMS). We performed a search in PubMed with the following MeSH terms: measurement, testosterone, androgen suppression and prostate cancer. We selected 12 studies that compared the metrological characteristics of various methods for quantifying serum testosterone compared with MS detection methods. IAs are standard tools for measuring testosterone levels; however, there is evidence that IAs lack accuracy and precision for quantifying low concentrations. Most chemiluminescent IAs overestimate their concentration, especially below 100ng/dL. The procedures that use LC-MSMS have an adequate lower quantification limit and proper accuracy and precision. We found no specific evidence in patients with PC who underwent castration. LC-MSMS is the appropriate method for quantifying low serum testosterone concentrations. We need to define the level of castration with this method and the optimal level related to better progression of the disease. Copyright © 2017 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.
Efficacy of Testosterone Suppression with Sustained-Release Triptorelin in Advanced Prostate Cancer.
Breul, Jürgen; Lundström, Eija; Purcea, Daniela; Venetz, Werner P; Cabri, Patrick; Dutailly, Pascale; Goldfischer, Evan R
2017-02-01
Androgen deprivation therapy (ADT) is a mainstay of treatment against advanced prostate cancer (PC). As a treatment goal, suppression of plasma testosterone levels to <50 ng/dl has been established over decades. Evidence is growing though that suppression to even lower levels may add further clinical benefit. Therefore, we undertook a pooled retrospective analysis on the efficacy of 1-, 3-, and 6-month sustained-release (SR) formulations of the gonadotropin-releasing hormone (GnRH) agonist triptorelin to suppress serum testosterone concentrations beyond current standards. Data of 920 male patients with PC enrolled in 9 prospective studies using testosterone serum concentrations as primary endpoint were pooled. Patients aged 42-96 years had to be eligible for ADT and to be either naïve to hormonal treatment or have undergone appropriate washout prior to enrolment. Patients were treated with triptorelin SR formulations for 2-12 months. Primary endpoints of this analysis were serum testosterone concentrations under treatment and success rates overall and per formulation, based on a testosterone target threshold of 20 ng/dl. After 1, 3, 6, 9, and 12 months of treatment, 79%, 92%, 93%, 90%, and 91% of patients reached testosterone levels <20 ng/dl, respectively. For the 1-, 3-, and 6-month formulations success rates ranged from 80-92%, from 83-93%, and from 65-97% with median (interquartile range) serum testosterone values of 2.9 (2.9-6.5), 5.0 (2.9-8.7), and 8.7 (5.8-14.1) ng/dl at study end, respectively. In the large majority of patients, triptorelin SR formulations suppressed serum testosterone concentrations to even <20 ng/dl. Testosterone should be routinely monitored in PC patients on ADT although further studies on the clinical benefit of very low testosterone levels and the target concentrations are still warranted.
Sayyid, Rashid K; Sayyid, Abdallah K; Klaassen, Zachary; Fadaak, Kamel; Goldberg, Hanan; Chandrasekar, Thenappan; Ahmad, Ardalanejaz; Leao, Ricardo; Perlis, Nathan; Chadwick, Karen; Hamilton, Robert J; Kulkarni, Girish S; Finelli, Antonio; Zlotta, Alexandre R; Fleshner, Neil E
2018-01-01
We determined whether men on continuous androgen deprivation therapy who achieve testosterone less than 0.7 nmol/l demonstrate subsequent testosterone elevations during followup and whether such events predict worse oncologic outcomes. We evaluated a random, retrospective sample of 514 patients with prostate cancer treated with continuous androgen deprivation therapy in whom serum testosterone was less than 0.7 nmol/l at University Health Network between 2007 and 2016. Patients were followed from the date of the first testosterone measurement of less than 0.7 nmol/l to progression to castrate resistance, death or study period end. Study outcomes were the development of testosterone elevations greater than 0.7, greater than 1.1 and greater than 1.7 nmol/l, and progression to a castrate resistant state. Survival curves were constructed to determine the rate of testosterone elevations. Multivariate Cox regression analysis was done to assess whether elevations predicted progression to castrate resistance. Median patient age was 74 years and median followup was 20.3 months. Within 5 years of followup 82%, 45% and 18% of patients had subsequent testosterone levels greater than 0.7, greater than 1.1 and greater than 1.7 nmol/l, respectively. In 96% to 100% of these patients levels less than 0.7 nmol/l were subsequently reestablished within 5 years. No patient baseline characteristic was associated with elevations and elevations were not a significant predictor of progression to a castrate resistant state. Men on continuous androgen deprivation therapy in whom initial testosterone is less than 0.7 nmol/l frequently show subsequent elevations in serum testosterone. Such a development should not trigger an immediate response from physicians as these events are prognostically insignificant with regard to oncologic outcomes. Levels are eventually reestablished at less than 0.7 nmol/l. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Pituitary, gonadal and adrenal hormones after prolonged residence at extreme altitude in man.
Basu, M; Pal, K; Prasad, R; Malhotra, A S; Rao, K S; Sawhney, R C
1997-06-01
High altitude-induced alterations in pituitary, gonadal and adrenal hormones were studied in (i) eugonadal men from the armed forces who were resident at sea level (SL), (ii) SL residents staying at an altitude of 3542 m for periods ranging from 3 to 12 months (acclimatized lowlanders, ALL), (iii) ALL who stayed at 6300 m for 6 months, (iv) ALL who trekked from 3542 to 5080 m and stayed at an altitude of more than 6300 m in the glacier region for 6 months, and (v) high-altitude natives (HAN) resident at an altitude of 3300-3700 m. Circulating levels of LH, FSH, prolactin, cortisol, testosterone, dihydrotestosterone (DHT) and progesterone in ALL at 3542 m and in HAN were not significantly different (p > 0.05) from the SL control values. When the ALL living at 3542 m trekked to an extreme altitude of 5080 m, their testosterone levels showed a significant decrease (p < 0.01) compared to the preceding altitude values but had returned to SL values when measured after 6 months' continuous stay at 6300 m. As with testosterone, the levels of DHT and oestradiol-17 beta (E2) after prolonged stay at extreme altitude were also not significantly different (p > 0.05) from the SL values. The LH levels after trekking to 5080 m were significantly higher (p < 0.01) than at an altitude of 3542 m, but decreased to levels found at 3542 m or SL after prolonged residence at extreme altitude. Plasma levels of ACTH, prolactin, FSH and cortisol on arrival at 5080 m, and after a 6-month stay at extreme altitude, were not significantly different (p > 0.05) from the SL values. Plasma progesterone levels tended to increase on arrival at 5080 m but a significant increase (p < 0.001) was evident only after a 6-month stay at extreme altitude. These observations suggest that prolonged residence at lower as well as at extreme altitude does not appreciably alter blood levels of pituitary, gonadal or adrenal hormones except for plasma levels of progesterone. The exact mechanism and significance of this increase remains unknown, but may be important in increasing the sensitivity of the hypoxic ventilatory response and activation of haemoglobin synthesis.
Kataoka, Tomoya; Hotta, Yuji; Maeda, Yasuhiro; Kimura, Kazunori
2017-12-01
Testosterone is believed to mediate the penile erectile response by producing adequate nitric oxide; therefore, testosterone deficiency results in erectile dysfunction through decreased nitric oxide bioavailability. However, the mechanisms underlying endothelial dysfunction in testosterone deficiency remain unclear. To investigate the mechanism of endothelial dysfunction in a rat model of testosterone deficiency. Rats were distributed into 3 groups: castrated (Cast), castrated and supplemented with testosterone (Cast + T), and sham (Sham). In the Cast + T group, castrated rats were treated daily with subcutaneous testosterone (3 mg/kg daily) for 4 weeks; Sham and Cast rats received only the vehicle. Erectile function using intracavernosal pressure and mean arterial pressure measurements after electrical stimulation of the cavernous nerve, endothelial function using isometric tension, asymmetric dimethylarginine (ADMA) levels using ultra-performance liquid chromatography and tandem mass spectrometry, and inflammatory biomarker expression were performed 4 weeks after the operation. In the Cast group, the ratio of intracavernosal pressure to mean arterial pressure significantly decreased, acetylcholine-induced relaxation was lower, and serum ADMA, oxidative stress, and inflammation biomarker levels were significantly increased (P < .01). Testosterone injection significantly improved each of these parameters (P < .01). The present results provide scientific evidence of the effect of testosterone deficiency on erectile function and the effect of testosterone replacement therapy. This study provides evidence of the influence of testosterone deficiency on endothelial function by investigating ADMA and oxidative stress. A major limitation of this study is the lack of a direct link of increased ADMA by oxidative stress to inflammation. Testosterone deficiency increased not only ADMA levels but also oxidative stress and inflammation in castrated rats, which can cause damage to the corpus cavernosum, resulting in erectile dysfunction. Kataoka T, Hotta Y, Maeda Y, Kimura K. Testosterone Deficiency Causes Endothelial Dysfunction via Elevation of Asymmetric Dimethylarginine and Oxidative Stress in Castrated Rats. J Sex Med 2017;14:1540-1548. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Grassi, Silvarosa; Frondaroli, Adele; Scarduzio, Mariangela; Dieni, Cristina V; Brecchia, Gabriele; Boiti, Cristiano; Pettorossi, Vito E
2012-02-10
We investigated the possible influence of sex and estrous cycle on the synaptic responses of neurons in the medial vestibular nucleus (MVN) and their long-term modifications. In brain stem slices of male and female rats during proestrus (PE) and diestrus (DE), we evaluated the field potential evoked in the MVN by vestibular afferent stimulation. Here we find that in PE females the field potential had a lower threshold and higher amplitude than in DE females and in males and also that the stimulus-response curve was shifted to the left. Such difference is related to the level and cyclic fluctuation of circulating 17β-estradiol (E(2)). This is supported by the exogenous administration of E(2) in DE females and males, with low levels of circulating E(2) that enhanced the field potential amplitude to values close to those of PE females. Sex and estrous cycle also influence the MVN synaptic plasticity. This has been shown by investigating the effect of testosterone (T) on the induction of long-term effects, since T is the precursor for the neural synthesis of E(2) (estrogenic pathway), which is involved in the induction of fast long-term potentiation (LTP), or of 5α-dihydrotestosterone (DHT, androgenic pathway) which mediates slow LTP and long-term depression (LTD). We found that T mostly induced LTD in PE females and no effect in DE females, while it only provoked fast LTP in males. We suggest that high level of circulating E(2) may interfere with the conversion of T, by inhibiting the neural estrogenic pathway and facilitating the androgenic one. On the whole these results demonstrate an influence of circulating E(2) on vestibular synaptic transmission and plasticity that in some cases may contribute to the sex and menstrual cycle dependence of symptoms in human vestibular pathology. Copyright © 2011 Elsevier Inc. All rights reserved.
ACTN3 GENOTYPE IS ASSOCIATED WITH TESTOSTERONE LEVELS OF ATHLETES
Donnikov, A.E.; Trofimov, D.Y.
2014-01-01
α-Actinin-3 (ACTN3) has been proposed to regulate skeletal muscle differentiation and hypertrophy through its interaction with the signalling protein calcineurin. Since the inhibition of calcineurin potentiates the production of testosterone, we hypothesized that α-actinin-3 deficiency (predicted from the ACTN3 XX genotype) may influence serum levels of testosterone of athletes. Objective: To investigate the association of ACTN3 gene R577X polymorphism with resting testosterone levels in athletes. Methods: A total of 209 elite Russian athletes from different sports (119 males, 90 females) were genotyped for ACTN3 gene R577X polymorphism by real-time PCR. Resting testosterone was examined in serum of athletes using enzyme immunoassay. Results: The mean testosterone levels were significantly higher in both males and females with the ACTN3 R allele than in XX homozygotes (males: RR: 24.9 (5.7), RX: 21.8 (5.5), XX: 18.6 (4.9) ng · mL-1, P = 0.0071; females: RR: 1.43 (0.6), RX: 1.21 (0.71), XX: 0.79 (0.66) ng · mL-1, P = 0.0167). Conclusions: We found that the ACTN3 R allele was associated with high levels of testosterone in athletes, and this may explain, in part, the association between the ACTN3 RR genotype, skeletal muscle hypertrophy and power athlete status. PMID:24899773
Guo, Wen; Bachman, Eric; Li, Michelle; Roy, Cindy N.; Blusztajn, Jerzy; Wong, Siu; Chan, Stephen Y.; Serra, Carlo; Jasuja, Ravi; Travison, Thomas G.; Muckenthaler, Martina U.; Nemeth, Elizabeta; Bhasin, Shalender
2013-01-01
Testosterone administration increases hemoglobin levels and has been used to treat anemia of chronic disease. Erythrocytosis is the most frequent adverse event associated with testosterone therapy of hypogonadal men, especially older men. However, the mechanisms by which testosterone increases hemoglobin remain unknown. Testosterone administration in male and female mice was associated with a greater increase in hemoglobin and hematocrit, reticulocyte count, reticulocyte hemoglobin concentration, and serum iron and transferring saturation than placebo. Testosterone downregulated hepatic hepcidin mRNA expression, upregulated renal erythropoietin mRNA expression, and increased erythropoietin levels. Testosterone-induced suppression of hepcidin expression was independent of its effects on erythropoietin or hypoxia-sensing mechanisms. Transgenic mice with liver-specific constitutive hepcidin over-expression failed to exhibit the expected increase in hemoglobin in response to testosterone administration. Testosterone upregulated splenic ferroportin expression and reduced iron retention in spleen. After intravenous administration of transferrin-bound 58Fe, the amount of 58Fe incorporated into red blood cells was significantly greater in testosterone-treated mice than in placebo-treated mice. Serum from testosterone-treated mice stimulated hemoglobin synthesis in K562 erythroleukemia cells more than that from vehicle-treated mice. Testosterone administration promoted the association of androgen receptor (AR) with Smad1 and Smad4 to reduce their binding to BMP-response elements in hepcidin promoter in the liver. Ectopic expression of AR in hepatocytes suppressed hepcidin transcription; this effect was blocked dose-dependently by AR antagonist flutamide. Testosterone did not affect hepcidin mRNA stability. Conclusion: Testosterone inhibits hepcidin transcription through its interaction with BMP-Smad signaling. Testosterone administration is associated with increased iron incorporation into red blood cells. PMID:23399021
2013-01-01
Background. Androgen receptor (AR) knockout male mice display hepatic steatosis, suggesting that AR signaling may regulate hepatic fat. However, the effects of testosterone replacement on hepatic fat in men are unknown. The aim of this study was to determine the effects of testosterone administration on hepatic fat in older men with mobility limitation and low testosterone levels who were participating in a randomized trial (the Testosterone in Older Men trial). Methods. Two hundred and nine men with mobility limitation and low total or free testosterone were randomized in the parent trial to either placebo or 10-g testosterone gel daily for 6 months. Hepatic fat was determined by magnetic resonance imaging in 73 men (36 in placebo and 37 in testosterone group) using the volumetric method. Insulin sensitivity (homeostatic model assessment–insulin resistance) was derived from fasting glucose and insulin. Results. Baseline characteristics were similar between the two groups, including liver volumes (1583±363 in the testosterone group vs 1522±271mL in the placebo group, p = .42). Testosterone concentrations increased from 250±72 to 632±363ng/dL in testosterone group but did not change in placebo group. Changes in liver volume during intervention did not differ significantly between groups (p = .5) and were not related to on-treatment testosterone concentrations. The change in homeostatic model assessment–insulin resistance also did not differ significantly between groups and was not related to either baseline or change in liver fat. Conclusion. Testosterone administration in older men with mobility limitation and low testosterone levels was not associated with a reduction in hepatic fat. Larger trials are needed to determine whether testosterone replacement improves liver fat in men with nonalcoholic hepatic steatosis. PMID:23292288
Association between serum total testosterone and Body Mass Index in middle aged healthy men
Shamim, Muhammad Omar; Ali Khan, Farooq Munfaet; Arshad, Rabia
2015-01-01
Objective: To determine correlation of serum total testosterone with body mass index (BMI) and waist hip ratio (WHR) in healthy adult males. Methods: A cross sectional study was conducted on 200 nonsmoker healthy males (aged 30-50 years) university employees. They were selected by convenience sampling technique after a detailed medical history and clinical examination including BMI and Waist Hip Ratio (WHR) calculation. Blood sampling was carried out to measure serum total testosterone (TT) using facilities of Chemiluminescence assay (CLIA) technique in Dow Chemical Laboratory. Independent sample T test was used for mean comparisons of BMI and WHR in between low and normal testosterone groups. (Subjects having < 9.7 nmol/L of total testosterone in blood were placed in low testosterone group and subjects having ≥ 9.7 nmol/L of total testosterone in blood were placed in normal testosterone group). Correlation of testosterone with BMI and WHR was analyzed by Pearson Correlation. Results: Mean (± SD) age of the subjects included in this study was 38.7 (± 6.563) years mean (± SD) total testosterone was 15.92 (±6.322)nmol/L. The mean (± SD) BMI, and WHR were 24.95 (±3.828) kg/m2 and 0.946 (±0.0474) respectively. Statistically significant differences were observed in the mean values of BMI and WHR for the two groups of testosterone. Significant inverse correlation of serum total testosterone with BMI(r = -0.311, p = 0.000) was recorded in this study. However testosterone was not significantly correlated with waist/hip ratio.(r = -0.126, p = 0.076) Conclusion: Middle age men working at DUHS who have low level of serum total testosterone are more obese than individuals with normal total testosterone level. PMID:26101490
High-testosterone men reject low ultimatum game offers.
Burnham, Terence C
2007-09-22
The ultimatum game is a simple negotiation with the interesting property that people frequently reject offers of 'free' money. These rejections contradict the standard view of economic rationality. This divergence between economic theory and human behaviour is important and has no broadly accepted cause. This study examines the relationship between ultimatum game rejections and testosterone. In a variety of species, testosterone is associated with male seeking dominance. If low ultimatum game offers are interpreted as challenges, then high-testosterone men may be more likely to reject such offers. In this experiment, men who reject low offers ($5 out of $40) have significantly higher testosterone levels than those who accept. In addition, high testosterone levels are associated with higher ultimatum game offers, but this second finding is not statistically significant.
Barone, Rosario; Pitruzzella, Alessandro; Marino Gammazza, Antonella; Rappa, Francesca; Salerno, Monica; Barone, Fulvio; Sangiorgi, Claudia; D'Amico, Daniela; Locorotondo, Nicola; Di Gaudio, Francesca; Cipolloni, Luigi; Di Felice, Valentina; Schiavone, Stefania; Rapisarda, Venerando; Sani, Gabriele; Tambo, Amos; Cappello, Francesco; Turillazzi, Emanuela; Pomara, Cristoforo
2017-08-01
The aim of this study was to investigate whether nandrolone decanoate (ND) use affects testosterone production and testicular morphology in a model of trained and sedentary mice. A group of mice underwent endurance training while another set led a sedentary lifestyle and were freely mobile within cages. All experimental groups were treated with either ND or peanut oil at different doses for 6 weeks. Testosterone serum levels were measured via liquid chromatography-mass spectrometry. Western blot analysis and quantitative real-time PCR were utilized to determine gene and protein expression levels of the primary enzymes implicated in testosterone biosynthesis and gene expression levels of the blood-testis barrier (BTB) components. Immunohistochemistry and immunofluorescence were conducted for testicular morphological evaluation. The study demonstrated that moderate to high doses of ND induced a diminished serum testosterone level and altered the expression level of the key steroidogenic enzymes involved in testosterone biosynthesis. At the morphological level, ND induced degradation of the BTB by targeting the tight junction protein-1 (TJP1). ND stimulation deregulated metalloproteinase-9, metalloproteinase-2 (MMP-2) and the tissue inhibitor of MMP-2. Moreover, ND administration resulted in a mislocalization of mucin-1. In conclusion, ND abuse induces a decline in testosterone production that is unable to regulate the internalization and redistribution of TJP1 and may induce the deregulation of other BTB constituents via the inhibition of MMP-2. ND may well be considered as both a potential inducer of male infertility and a potential risk factor to a low endogenous bioavailable testosterone. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.
Lorzadeh, Nahid; Kazemirad, Sirous
2012-01-01
Introduction. The aim of the present study was to evaluate the effects of fetal sex on serum human chorionic gonadotropin (hCG) and testosterone in normotensive and preeclamptic pregnancies. Materials and Methods. This is a cross-sectional study and 139 women with singleton pregnancies in the third trimester were studied. Seventy-one pregnancies were uncomplicated; among those were 35 male and 36 female fetuses. Sixty-eight pregnancies were complicated by preeclampsia; among those were 35 male and 33 female fetuses. Human chorionic gonadotropin and total testosterone were measured in maternal peripheral blood. Data analyzed by SPSS software. Results. In male-bearing pregnancies, maternal hCG and testosterone serum levels were significantly higher in preeclamptic than normotensive mothers (P < 0.001 and P < 0.001, resp.) in female-bearing pregnancies testosterone levels were significantly higher in preeclamptic than normotensive mothers (P < 0.001). Total testosterone levels were significantly higher in pregnancies with either gender and significantly higher in mlae-bearing than in female-bearing pregnancies. Conclusion. According to our results, there is a correlation between maternal serum hCG and testosterone levels and preeclampsia. Therefore these tests can be used as routine during 30–38 weeks of gestation. High maternal serum concentrations of these markers can predict preeclampsia. PMID:22518314
Afrisham, Reza; Sadegh-Nejadi, Sahar; SoliemaniFar, Omid; Kooti, Wesam; Ashtary-Larky, Damoon; Alamiri, Fatima; Najjar-Asl, Sedigheh; Khaneh-Keshi, Ali
2016-01-01
Objective The purpose of this study was to evaluate the salivary testosterone levels under psychological stress and its relationship with rumination and five personality traits in medical students. Methods A total of 58 medical students, who wanted to participate in the final exam, were selected by simple random sampling. Two months before the exam, in the basal conditions, the NEO Inventory short form, and the Emotional Control Questionnaire (ECQ) were completed. Saliva samples were taken from students in both the basal conditions and under exam stress. Salivary testosterone was measured by ELISA. Data was analyzed using multivariate analysis of variance with repeated measures, paired samples t-test, Pearson correlation and stepwise regression analysis. Results Salivary testosterone level of men showed a significant increase under exam stress (p<0.05). However, a non-significant although substantial reduction observed in women. A significant correlation was found between extroversion (r=-0.33) and openness to experience (r=0.30) with salivary testosterone (p<0.05). Extraversion, aggression control and emotional inhibition predicted 28% of variance of salivary testosterone under stress. Conclusion Salivary testosterone reactivity to stress can be determined by sexual differences, personality traits, and emotional control variables which may decrease or increase stress effects on biological responses, especially the salivary testosterone. PMID:27909455
White, Hillary D; Brown, Lin A J; Gyurik, Robert J; Manganiello, Paul D; Robinson, Thomas D; Hallock, Linda S; Lewis, Lionel D; Yeo, Kiang-Teck J
2015-08-01
To test our hypothesis that testosterone deficiency plays an important role in chronic pain, a Phase I/II pilot study was initiated with 12 fibromyalgia patients to verify that a daily dose for 28days with transdermal testosterone gel would 1) significantly and safely increase mean serum testosterone concentrations from low baseline levels to mid/high-normal levels, and 2) effectively treat the pain and fatigue symptoms of fibromyalgia. Pharmacokinetic data confirmed that serum free testosterone concentrations were raised significantly above baseline levels, by assessment of maximum hormone concentration (Cmax) and area under the curve (AUC) parameters: free testosterone Cmax was significantly raised from a mean of 2.64pg/mL to 3.91pg/mL (p<0.05), and 24hour free testosterone AUC was significantly raised from a mean of 35.0pg-hr/mL to 53.89pg-hr/mL. Assessment of the typical symptoms of fibromyalgia by patient questionnaire and tender point exam demonstrated significant change in: decreased muscle pain, stiffness, and fatigue, and increased libido during study treatment. These results are consistent with the hypothesized ability of testosterone to relieve the symptoms of fibromyalgia. Symptoms not tightly related to fibromyalgia were not improved. Copyright © 2015. Published by Elsevier B.V.
Zhao, Jing; Liu, Ge-Li; Wei, Ying; Jiang, Li-Hong; Bao, Peng-Li; Yang, Qing-Yan
2016-09-01
The aim of the present study was to investigate the effect of testosterone on glucolipid metabolism and vascular injury in male rats, and examine the underlying molecular mechanisms. A total of 40 male Sprague-Dawley rats were divided into a control group (n=10), high-fat-diet + castration group (n=10), high‑fat‑diet + castration + low dose testosterone group (n=10), and high-fat-diet + castration + high dose testosterone group (n=10). Hematoxylin and eosin staining was performed to evaluate the morphology of the thoracic aortic tissues. Immunohistochemical staining was used to detect biomarkers of the phosphoinositide 3‑kinase (PI3K) signaling pathway. The mRNA and protein expression levels of PI3K, AKT, insulin receptor substrate‑1 (IRS‑1), glucose transporter type 4 (GLUT‑4), nuclear factor (NF)‑κB and tumor necrosis factor (TNF)‑α in the aortas were determined using quantitative polymerase chain reaction and Western blot analyses, respectively. Apoptosis in the aortic tissues was detected using a TUNEL assay. Castration induced apoptosis in the animals fed a high‑fat‑diet, whereas low dose testosterone replacement ameliorated the apoptosis in the aorta. However, the levels of apoptosis was more severe following high‑dose testosterone treatment. Low‑dose testosterone induced upregulation in the levels of IRS‑1, AKT, GLUT‑4 protein, NF‑κB, TNF‑α and PI3K, compared with those in the animals fed a high‑fat diet following castration. A high dose of testosterone resulted in a significant decrease in the levels of IRS‑1, AKT, GLUT‑4, NF‑κB, TNF‑α and PI3K. Compared with the rats in the high‑fat diet + castration group, a low dose of testosterone induced upregulation in the mRNA levels of IRS‑1, AKT and GLUT‑4, and downregulation of the mRNA levels of NF‑κB, TNF‑α and PI3K. A high dose of testosterone resulted in a significant decrease in the levels of IRS‑1, AKT and GLUT‑4, and marked increases in the mRNA levels of NF‑κB, TNF‑α and PI3K, compared with the low dose group. Castration induced marked disorders of glucolipid metabolism and vascular injuries in the pubescent male rats. Low‑dose testosterone treatment was found to ameliorate the vascular damage caused by castration via the PI3K/AKT signaling pathway.
Veiga-Lopez, Almudena; Steckler, Teresa L; Abbott, David H; Welch, Kathleen B; MohanKumar, Puliyur S; Phillips, David J; Refsal, Kent; Padmanabhan, Vasantha
2011-01-01
Prenatal testosterone excess in sheep leads to reproductive and metabolic disruptions that mimic those seen in women with polycystic ovary syndrome. Comparison of prenatal testosterone-treated sheep with prenatal dihydrotestosterone-treated sheep suggests facilitation of defects by androgenic as well as androgen-independent effects of testosterone. We hypothesized that the disruptive impact of prenatal testosterone on adult pathology may partially depend on its conversion to estrogen and consequent changes in maternal and fetal endocrine environments. Pregnant Suffolk sheep were administered either cottonseed oil (control) or testosterone propionate in cottonseed oil (100 mg, i.m. twice weekly), from Day 30 to Day 90 of gestation (term is ~147 d). Maternal (uterine) and fetal (umbilical) arterial samples were collected at Days 64-66, 87-90, and 139-140 (range; referred to as D65, D90, and D140, respectively) of gestation. Concentrations of gonadal and metabolic hormones, as well as differentiation factors, were measured using liquid chromatography/mass spectrometer, radioimmunoassay, or ELISA. Findings indicate that testosterone treatment produced maternal and fetal testosterone levels comparable to adult males and D65 control male fetuses, respectively. Testosterone treatment increased fetal estradiol and estrone levels during the treatment period in both sexes, supportive of placental aromatization of testosterone. These steroidal changes were followed by a reduction in maternal estradiol levels at term, a reduction in activin A availability, and induction of intrauterine growth restriction in D140 female fetuses. Overall, our findings provide the first direct evidence in support of the potential for both androgenic as well as estrogenic contribution in the development of adult reproductive and metabolic pathology in prenatal testosterone-treated sheep.
Veiga-Lopez, Almudena; Steckler, Teresa L.; Abbott, David H.; Welch, Kathleen B.; MohanKumar, Puliyur S.; Phillips, David J.; Refsal, Kent; Padmanabhan, Vasantha
2010-01-01
Prenatal testosterone excess in sheep leads to reproductive and metabolic disruptions that mimic those seen in women with polycystic ovary syndrome. Comparison of prenatal testosterone-treated sheep with prenatal dihydrotestosterone-treated sheep suggests facilitation of defects by androgenic as well as androgen-independent effects of testosterone. We hypothesized that the disruptive impact of prenatal testosterone on adult pathology may partially depend on its conversion to estrogen and consequent changes in maternal and fetal endocrine environments. Pregnant Suffolk sheep were administered either cottonseed oil (control) or testosterone propionate in cottonseed oil (100 mg, i.m. twice weekly), from Day 30 to Day 90 of gestation (term is ∼147 d). Maternal (uterine) and fetal (umbilical) arterial samples were collected at Days 64–66, 87–90, and 139–140 (range; referred to as D65, D90, and D140, respectively) of gestation. Concentrations of gonadal and metabolic hormones, as well as differentiation factors, were measured using liquid chromatography/mass spectrometer, radioimmunoassay, or ELISA. Findings indicate that testosterone treatment produced maternal and fetal testosterone levels comparable to adult males and D65 control male fetuses, respectively. Testosterone treatment increased fetal estradiol and estrone levels during the treatment period in both sexes, supportive of placental aromatization of testosterone. These steroidal changes were followed by a reduction in maternal estradiol levels at term, a reduction in activin A availability, and induction of intrauterine growth restriction in D140 female fetuses. Overall, our findings provide the first direct evidence in support of the potential for both androgenic as well as estrogenic contribution in the development of adult reproductive and metabolic pathology in prenatal testosterone-treated sheep. PMID:20739662
Reimers, Luise; Diekhof, Esther K.
2015-01-01
The steroid hormone testosterone is widely associated with negative behavioral effects, such as aggression or dominance. However, recent studies applying economic exchange tasks revealed conflicting results. While some point to a prosocial effect of testosterone by increasing altruistic behavior, others report that testosterone promotes antisocial tendencies. Taking into account additional factors such as parochial altruism (i.e., ingroup favoritism and outgroup hostility) might help to explain this contradiction. First evidence for a link between testosterone and parochial altruism comes from recently reported data of male soccer fans playing the ultimatum game. In this study high levels of endogenous testosterone predicted increased altruistic punishment during outgroup interactions and at the same time heightened ingroup generosity. Here, we report findings of another experimental task, the prisoner's dilemma, applied in the same context to examine the role of testosterone on parochial tendencies in terms of cooperation. In this task, 50 male soccer fans were asked to decide whether or not they wanted to cooperate with partners marked as either fans of the subject's own favorite team (ingroup) or fans of other teams (outgroups). Our results show that high testosterone levels were associated with increased ingroup cooperation during intergroup competition. In addition, subjects displaying a high degree of parochialism during intergroup competition had significantly higher levels of testosterone than subjects who did not differentiate much between the different groups. In sum, the present data demonstrate that the behavioral effects of testosterone are not limited to aggressive and selfish tendencies but may imply prosocial aspects depending on the context. By this means, our results support the previously reported findings on testosterone-dependent intergroup bias and indicate that this social hormone might be an important factor driving parochial altruism. PMID:26124701
Reimers, Luise; Diekhof, Esther K
2015-01-01
The steroid hormone testosterone is widely associated with negative behavioral effects, such as aggression or dominance. However, recent studies applying economic exchange tasks revealed conflicting results. While some point to a prosocial effect of testosterone by increasing altruistic behavior, others report that testosterone promotes antisocial tendencies. Taking into account additional factors such as parochial altruism (i.e., ingroup favoritism and outgroup hostility) might help to explain this contradiction. First evidence for a link between testosterone and parochial altruism comes from recently reported data of male soccer fans playing the ultimatum game. In this study high levels of endogenous testosterone predicted increased altruistic punishment during outgroup interactions and at the same time heightened ingroup generosity. Here, we report findings of another experimental task, the prisoner's dilemma, applied in the same context to examine the role of testosterone on parochial tendencies in terms of cooperation. In this task, 50 male soccer fans were asked to decide whether or not they wanted to cooperate with partners marked as either fans of the subject's own favorite team (ingroup) or fans of other teams (outgroups). Our results show that high testosterone levels were associated with increased ingroup cooperation during intergroup competition. In addition, subjects displaying a high degree of parochialism during intergroup competition had significantly higher levels of testosterone than subjects who did not differentiate much between the different groups. In sum, the present data demonstrate that the behavioral effects of testosterone are not limited to aggressive and selfish tendencies but may imply prosocial aspects depending on the context. By this means, our results support the previously reported findings on testosterone-dependent intergroup bias and indicate that this social hormone might be an important factor driving parochial altruism.
Testosterone, territoriality, and the 'home advantage'.
Neave, Nick; Wolfson, Sandy
2003-02-01
The consistently better performance seen by teams in various sporting contexts when playing at home is referred to as the 'home advantage'. Various explanations have been put forward to account for this robust phenomenon, though none has yet focussed on possible hormonal factors. In an initial study, we showed that salivary testosterone levels in soccer players were significantly higher before a home game than an away game.In a second study involving a different group of soccer players, this finding was replicated over two home games, two away games, and three training sessions. Perceived rivalry of the opposing team was important as testosterone levels were higher before playing an 'extreme' rival than a 'moderate' rival. Self-reported measures of mood in both studies were not linked to testosterone level. The present results corroborate and extend earlier findings on the relationships between testosterone, territoriality, and dominance in human competitive encounters and further suggest an important role for testosterone in the home advantage seen in various team sports.
Anel-López, L; Ortega-Ferrusola, C; Martínez-Rodríguez, C; Álvarez, M; Borragán, S; Chamorro, C; Peña, F J; Anel, L; de Paz, P
2017-01-01
Seminal plasma (SP) plays an important role in the motility, viability and maintenance of the fertilizing capacity of mammalian spermatozoa. This study is the first on brown bear (Ursus arctos) SP components, and has two main objectives: 1) to define the SP composition in bear ejaculate and 2) to identify variations in SP composition in relation to high and low levels of testosterone in serum during the breeding season. Forty-eight sperm samples from 30 sexually mature male brown bears (Ursus arctos) were obtained by electroejaculation, and their serum testosterone levels were assessed to sort the animals into 2 groups (high and low testosterone levels, threshold 5 ng/dl). The biochemical and protein compositions of the SP samples were assessed, and sperm motility was analyzed. We found that lactate dehydrogenase was significantly higher in the low-serum-testosterone samples, while concentrations of lipase and Mg+ values were significantly higher in the high-serum-testosterone samples. In contrast, sperm motility did not significantly differ (P>0.05) between the testosterone level groups (total motility: 74.42.8% in the high-level group vs. 77.1±4.7% in the low-level group). A reference digital model was constructed since there is no information for this wild species. To do this, all gel images were added in a binary multidimensional image and thirty-three spots were identified as the most-repeated spots. An analysis of these proteins was done by qualitative equivalency (isoelectric point and molecular weight) with published data for a bull. SP protein composition was compared between bears with high and low serum testosterone, and three proteins (binder of sperm and two enzymes not identified in the reference bull) showed significant (P<0.05) quantitative differences. We conclude that male bears with high or low serum testosterone levels differs only in some properties of their SP, differences in enzyme LDIP2, energy source LACT2, one protein (similar to BSP1) and Mg ion were identified between these two groups. These data may inform the application of SP to improve bear semen extenders.
Triptorelin embonate (6-month formulation).
Keating, Gillian M
2010-02-12
A 6-month formulation of the gonadotropin-releasing hormone agonist triptorelin embonate (designed to deliver 22.5 mg of triptorelin over a 6-month period) has been developed for use in the treatment of advanced prostate cancer. Following intramuscular administration of the 6-month formulation of triptorelin embonate 22.5 mg to men with advanced prostate cancer (subset of 15 patients from the pivotal clinical trial), serum testosterone levels initially increased, followed by a rapid, sustained decrease. Castrate serum testosterone levels (i.e. < or =1.735 nmol/L) were achieved in a geometric mean time of 18.8 days. The 6-month formulation of triptorelin embonate achieved and maintained castrate serum testosterone levels in patients with advanced prostate cancer (n = 120), according to the results of the pivotal, noncomparative, multicentre trial (patients received intramuscular triptorelin embonate 22.5 mg on day 1 and at month 6 [week 24]). By day 29, 97.5% of patients had castrate serum testosterone levels. Castrate serum testosterone levels were maintained from months 2 to 12 in 93.0% of patients. Prior to the second injection at month 6, 98.3% of patients had castrate serum testosterone levels, and 98.3% of patients had castrate serum testosterone levels at study completion. The 6-month formulation of triptorelin embonate 22.5 mg was generally well tolerated in patients with advanced prostate cancer; adverse events were of mild severity in the majority of patients. Drug-related adverse events (e.g. hot flushes) were consistent with the pharmacological action of triptorelin. Injection-site reactions occurred in 6.7% of triptorelin embonate recipients.
Age related testosterone level changes and male andropause syndrome.
Wu, C Y; Yu, T J; Chen, M J
2000-06-01
Much like the menopause syndrome occurring among older women, a similar condition has been defined among men. Testosterone production increases rapidly at the onset of puberty, then dwindles quickly after age 50 to become 20 to 50% of the peak level by age 80. Many men older than age 50 have experienced frailty syndrome, which includes decrease of libido, easy fatigue, mood disturbance, accelerated osteoporosis, and decreased muscle strength. We investigated serum total testosterone levels and andropause syndrome in men. Serum total testosterone levels were measured in 53 symptomatic men older than age 50 and in 48 men younger than age 40 for a control group. We also analyzed andropause symptoms among the 53 men older than age 50. The mean serum total testosterone level in the symptomatic men older than age 50 (mean: 2.68 +/- 0.51 ng/ml, range: 1.21 to 4.13 ng/ml) was significantly lower than that in the control group (mean: 7.01 +/- 0.82 ng/ml, range: 5.53 ng/ml to 8.14 ng/ml). Male frailty syndrome in these men older than 50 included: decreased libido (91%), lack of energy (89%), erection problems (79%), falling asleep after dinner (77%), memory impairment (77%), loss of pubic hair (70%), sad or grumpy mood changes (68%), decrease in endurance (66%), loss of axillary hair (55%), and deterioration in work performance (51%). The serum total testosterone level showed a decline with aging, especially in the men older than age 50. Low serum testosterone levels were also associated with the symptoms of male andropause syndrome.
Can treatment of nocturia increase testosterone level in men with late onset hypogonadism?
Kim, Jong Wook; Chae, Ji Yun; Kim, Jin Wook; Yoon, Cheol Yong; Oh, Mi Mi; Park, Hong Seok; Kim, Je Jong; Moon, Du Geon
2014-04-01
To assess the effect of desmopressin on serum testosterone level in men with nocturia and late onset hypogonadism. We prospectively enrolled men with nocturia and symptoms of late onset hypogonadism. Desmopressin (0.1 mg) was administered once daily to patients for 12 weeks, and we then compared serum testosterone levels, electrolytes, frequency volume chart indices, and changes in the International Prostate Symptom Score (IPSS), International Index of Erectile Function, and Aging Male's Symptom scales before and after treatment. Patients with a history of cardiovascular disease or hyponatremia, those using hypnotics, and those who had primary hypogonadism or hypogonadotrophic hypogonadism were excluded from the study. Sixty-two men (mean age, 68.4 years) completed pre- and post-treatment questionnaires and underwent laboratory testing. At the end of the study, the testosterone levels in men with low testosterone levels (<3.5 ng/mL) increased after the 12-week desmopressin treatment (2.85 ± 0.58 to 3.97 ± 1.44 ng/mL; P = .001). Mean scores had decreased from 17.7 to 13.9 (IPSS), 3.8 to 3.2 (IPSS-Quality of Life), and 33.7 to 31.1 (Aging Male's Symptom). On the frequency volume chart, nocturnal urine volume, nocturnal polyuria index, actual number of nocturia events, nocturia index, and nocturnal bladder capacity index were significantly decreased. Desmopressin improved nocturia and other urinary symptoms. Moreover, serum testosterone levels increased significantly in men with low testosterone levels after 12-week desmopressin treatment. Copyright © 2014 Elsevier Inc. All rights reserved.
Rosvall, K A; Bergeon Burns, C M; Barske, J; Goodson, J L; Schlinger, B A; Sengelaub, D R; Ketterson, E D
2012-09-07
Testosterone (T) regulates many traits related to fitness, including aggression. However, individual variation in aggressiveness does not always relate to circulating T, suggesting that behavioural variation may be more closely related to neural sensitivity to steroids, though this issue remains unresolved. To assess the relative importance of circulating T and neural steroid sensitivity in predicting behaviour, we measured aggressiveness during staged intrusions in free-living male and female dark-eyed juncos (Junco hyemalis). We compared aggressiveness to plasma T levels and to the abundance of androgen receptor (AR), aromatase (AROM) and oestrogen receptor alpha (ORα) mRNA in behaviourally relevant brain areas (avian medial amygdala, hypothalamus and song control regions). We also asked whether patterns of covariation among behaviour and endocrine parameters differed in males and females, anticipating that circulating T may be a better predictor of behaviour in males than in females. We found that circulating T related to aggressiveness only in males, but that gene expression for ORα, AR and AROM covaried with individual differences in aggressiveness in both sexes. These findings are among the first to show that individual variation in neural gene expression for three major sex steroid-processing molecules predicts individual variation in aggressiveness in both sexes in nature. The results have broad implications for our understanding of the mechanisms by which aggressive behaviour may evolve.
Metabolic Evidence of Diminished Lipid Oxidation in Women With Polycystic Ovary Syndrome
Whigham, Leah D.; Butz, Daniel E.; Dashti, Hesam; Tonelli, Marco; Johnson, LuAnn K.; Cook, Mark E.; Porter, Warren P.; Eghbalnia, Hamid R.; Markley, John L.; Lindheim, Steven R.; Schoeller, Dale A.; Abbott, David H.; Assadi-Porter, Fariba M.
2014-01-01
Polycystic ovary syndrome (PCOS), a common female endocrinopathy, is a complex metabolic syndrome of enhanced weight gain. The goal of this pilot study was to evaluate metabolic differences between normal (n=10) and PCOS (n=10) women via breath carbon isotope ratio, urinary nitrogen and nuclear magnetic resonance (NMR)-determined serum metabolites. Breath carbon stable isotopes measured by cavity ring down spectroscopy (CRDS) indicated diminished (p<0.030) lipid use as a metabolic substrate during overnight fasting in PCOS compared to normal women. Accompanying urinary analyses showed a trending correlation (p<0.057) between overnight total nitrogen and circulating testosterone in PCOS women, alone. Serum analyzed by NMR spectroscopy following overnight, fast and at 2 h following an oral glucose tolerance test showed that a transient elevation in blood glucose levels decreased circulating levels of lipid, glucose and amino acid metabolic intermediates (acetone, 2-oxocaporate, 2-aminobutyrate, pyruvate, formate, and sarcosine) in PCOS women, whereas the 2 h glucose challenge led to increases in the same intermediates in normal women. These pilot data suggest that PCOS-related inflexibility in fasting-related switching between lipid and carbohydrate/protein utilization for carbon metabolism may contribute to enhanced weight gain. PMID:24765590
USDA-ARS?s Scientific Manuscript database
Context: Biomarkers that predict musculoskeletal response to anabolic therapies should expedite drug development. During collagen synthesis in soft lean tissue, N-terminal propeptide of type III procollagen (P3NP) is released into circulation. We investigated P3NP as a biomarker of lean body mass (L...
ERIC Educational Resources Information Center
Hines, Melissa; Golombok, Susan; Rust, John; Johnston, Katie J.; Golding, Jean
2002-01-01
Related blood levels of testosterone and sex hormone-binding globulin in pregnant women to gender role behavior among 342 male and 337 female offspring at 3.5 years. Found that testosterone levels related linearly to girls' gender role behavior. Neither hormone related to boys' gender role behavior. Other factors, including older brothers or…
Testosterone, migration distance, and migratory timing in song sparrows Melospiza melodia.
Lymburner, Alannah H; Kelly, Tosha R; Hobson, Keith A; MacDougall-Shackleton, Elizabeth A; MacDougall-Shackleton, Scott A
2016-09-01
In seasonally migratory animals, migration distance often varies substantially within populations such that individuals breeding at the same site may overwinter different distances from the breeding grounds. Shorter migration may allow earlier return to the breeding grounds, which may be particularly advantageous to males competing to acquire a breeding territory. However, little is known about potential mechanisms that may mediate migration distance. We investigated naturally-occurring variation in androgen levels at the time of arrival to the breeding site and its relationship to overwintering latitude in male and female song sparrows (Melospiza melodia). We used stable isotope analysis of hydrogen (δ(2)H) in winter-grown claw tissue to infer relative overwintering latitude (migration distance), combined with 14years of capture records from a long-term study population to infer the arrival timing of males versus females. Relative to females, males had higher circulating androgen levels, migrated shorter distances, and were more likely to be caught early in the breeding season. Males that migrate short distances may benefit from early arrival at the breeding grounds, allowing them to establish a breeding territory. Even after controlling for sex and date, androgen levels were highest in individuals that migrated shorter distances. Our findings indicate that androgens and migration distance are correlated traits within and between sexes that may reflect individual variation within an integrated phenotype in which testosterone has correlated effects on behavioral traits such as migration. Copyright © 2016 Elsevier Inc. All rights reserved.
... test measures the blood level of the male sex hormone testosterone. Testosterone, which plays an important role in sexual development, is produced mainly by the testes in boys and in much smaller amounts by the ovaries ...
Testosterone and Child and Adolescent Adjustment: The Moderating Role of Parent-Child Relationships.
ERIC Educational Resources Information Center
Booth, Alan; Johnson, David R.; Granger, Douglas A.; Crouter, Ann C.; McHale, Susan
2003-01-01
In a sample of families with 6- to 18-year-olds, this study found that sons' and daughters' testosterone levels showed little direct connection to risk behavior or depressive symptoms. As parent-child relationship quality increased, testosterone-related adjustment problems were less evident. When relationship quality decreased, testosterone-linked…
Walsh, Thomas J; Shores, Molly M; Krakauer, Chloe A; Forsberg, Christopher W; Fox, Alexandra E; Moore, Kathryn P; Korpak, Anna; Heckbert, Susan R; Zeliadt, Steven B; Kinsey, Chloe E; Thompson, Mary Lou; Smith, Nicholas L; Matsumoto, Alvin M
2018-01-01
Testosterone treatment of men with low testosterone is common and, although relatively short-term, has raised concern regarding an increased risk of prostate cancer (CaP). We investigated the association between modest-duration testosterone treatment and incident aggressive CaP. Retrospective inception cohort study of male Veterans aged 40 to 89 years with a laboratory-defined low testosterone measurement from 2002 to 2011 and recent prostate specific antigen (PSA) testing; excluding those with recent testosterone treatment, prostate or breast cancer, high PSA or prior prostate biopsy. Histologically-confirmed incident aggressive prostate cancer or any prostate cancer were the primary and secondary outcomes, respectively. Of the 147,593 men included, 58,617 were treated with testosterone. 313 aggressive CaPs were diagnosed, 190 among untreated men (incidence rate (IR) 0.57 per 1000 person years, 95% CI 0.49-0.65) and 123 among treated men (IR 0.58 per 1000 person years; 95% CI 0.48-0.69). After adjusting for age, race, hospitalization during year prior to cohort entry, geography, BMI, medical comorbidities, repeated testosterone and PSA testing, testosterone treatment was not associated with incident aggressive CaP (HR 0.89; 95% CI 0.70-1.13) or any CaP (HR 0.90; 95% CI 0.81-1.01). No association between cumulative testosterone dose or formulation and CaP was observed. Among men with low testosterone levels and normal PSA, testosterone treatment was not associated with an increased risk of aggressive or any CaP. The clinical risks and benefits of testosterone treatment can only be fully addressed by large, longer-term randomized controlled trials.
Ibebunjo, Chikwendu; Eash, John K; Li, Christine; Ma, QiCheng; Glass, David J
2011-02-01
Declines in skeletal muscle size and strength, often seen with chronic wasting diseases, prolonged or high-dose glucocorticoid therapy, and the natural aging process in mammals, are usually associated with reduced physical activity and testosterone levels. However, it is not clear whether the decline in testosterone and activity are causally related. Using a mouse model, we found that removal of endogenous testosterone by orchidectomy results in an almost complete cessation in voluntary wheel running but only a small decline in muscle mass. Testosterone replacement restored running behavior and muscle mass to normal levels. Orchidectomy also suppressed the IGF-I/Akt pathway, activated the atrophy-inducing E3 ligases MuRF1 and MAFBx, and suppressed several energy metabolism pathways, and all of these effects were reversed by testosterone replacement. The study also delineated a distinct, previously unidentified set of genes that is inversely regulated by orchidectomy and testosterone treatment. These data demonstrate the necessity of testosterone for both speed and endurance of voluntary wheel running in mice and suggest a potential mechanism for declined activity in humans where androgens are deficient.
Liu, Tao; Cui, Yu-qian; Zhao, Han; Liu, Hong-bin; Zhao, Shi-dou; Gao, Yuan; Mu, Xiao-li; Gao, Fei; Chen, Zi-jiang
2015-10-01
The effect of high concentrations of testosterone on ovarian follicle development was investigated. Primary follicles and granulosa cells were cultured in vitro in media supplemented with a testosterone concentration gradient. The combined effects of testosterone and follicle-stimulating hormone (FSH) on follicular growth and granulosa cell gonadotropin receptor mRNA expression were also investigated. Follicle growth in the presence of high testosterone concentrations was promoted at early stages (days 1-7), but inhibited at later stage (days 7-14) of in vitro culture. Interestingly, testosterone-induced follicle development arrest was rescued by treatment with high concentrations of FSH (400 mIU/mL). In addition, in cultured granulosa cells, high testosterone concentrations induced cell proliferation, and increased the mRNA expression level of FSH receptor (FSHR), and luteinized hormone/choriogonadotropin receptor. It was concluded that high concentrations of testosterone inhibited follicle development, most likely through regulation of the FSH signaling pathway, although independently from FSHR downregulation. These findings are an important step in further understanding the pathogenesis of polycystic ovary syndrome.
Free testosterone as marker of adaptation to medium-intensive exercise.
Shkurnikov, M U; Donnikov, A E; Akimov, E B; Sakharov, D A; Tonevitsky, A G
2008-09-01
A 4-week study of adaptation reserves of the body was carried out during medium intensive exercise (medium intensive training: 60-80% threshold anaerobic metabolism). Two groups of athletes were singled out by the results of pulsometry analysis: with less than 20% work duration at the level above the 80% threshold anaerobic metabolism and with more than 20% work duration at the level above 80% threshold anaerobic metabolism. No appreciable differences between the concentrations of total testosterone, growth hormone, and cortisol before and after exercise in the groups with different percentage of anaerobic work duration were detected. In group 1 the concentrations of free testosterone did not change throughout the period of observation in comparison with the levels before training. In group 2, the level of free testosterone increased in comparison with the basal level: from 0.61+/-0.12 nmol/liter at the end of week 1 to 0.98+/-0.11 nmol/liter at the end of week 4 (p<0.01). The results indicate that the level of free testosterone can be used for evaluating the degree of athlete's adaptation to medium intensive exercise.
Nofsinger, John R; Patterson, Fernando M; Shank, Corey A
2018-05-01
We examine the relation between testosterone, cortisol, and financial decisions in a sample of naïve investors. We find that testosterone level is positively related to excess risk-taking, whereas cortisol level is negatively related to excess risk-taking (correlation coefficient [r]: 0.75 and -0.21, respectively). Additionally, we find support for the dual-hormone hypothesis in a financial context. Specifically, the testosterone-to-cortisol ratio is significantly related to loss aversion. Individuals with a higher ratio are 3.4 times more likely to sell losing stocks (standard error [SE]: 1.63). Furthermore, we find a positive feedback loop between financial success, testosterone, and cortisol. Specifically, financial success is significantly related to higher post-trial testosterone and cortisol by a factor of 0.53 (SE: 0.14). Finally, we find that in a competitive environment, testosterone level increases significantly, leading to greater risk-taking than in noncompetitive environment. Overall, this study underscores the importance of the endocrine system on financial decision-making. The results of this study are relevant to a broad audience, including investors looking to optimize financial performance, industry human resources, market regulators, and researchers. Copyright © 2018 Elsevier B.V. All rights reserved.
Quispe, Rene; Trappschuh, Monika; Gahr, Manfred; Goymann, Wolfgang
2015-02-01
Hormone manipulations are of increasing interest in the areas of physiological ecology and evolution, because hormones are mediators of complex phenotypic changes. Often, however, hormone manipulations in field settings follow the approaches that have been used in classical endocrinology, potentially using supra-physiological doses. To answer ecological and evolutionary questions, it may be important to manipulate hormones within their physiological range. We compare the release dynamics of three kinds of implants, silastic tubing, time-release pellets, and beeswax pellets, each containing 3mg of testosterone. These implants were placed into female Japanese quail, and plasma levels of testosterone measured over a period of 30 days. Testosterone in silastic tubing led to supraphysiological levels. Also, testosterone concentrations were highly variable between individuals. Time-release pellets led to levels of testosterone that were slightly supraphysiological during the first days. Over the period of 30 days, however, testosterone concentrations were more consistent. Beeswax implants led to a physiological increase in testosterone and a relatively constant release. The study demonstrated that hormone implants in 10mm silastic tubing led to a supraphysiological peak in female quail. Thus, the use of similar-sized or even larger silastic implants in males or in other smaller vertebrates needs careful assessment. Time-release pellets and beeswax implants provide a more controlled release and degrade within the body. Thus, it is not necessary to recapture the animal to remove the implant. We propose beeswax implants as an appropriate procedure to manipulate testosterone levels within the physiological range. Hence, such implants may be an effective alternative for field studies. Copyright © 2015 Elsevier Inc. All rights reserved.
Hamlin, Heather J; Edwards, Thea M; McCoy, Jessica; Cruze, Lori; Guillette, Louis J
2016-11-01
Anthropogenic nitrogen is a ubiquitous environmental contaminant that is contributing to the degradation of freshwater, estuarine, and coastal ecosystems worldwide. The effects of environmental nitrate, a principal form of nitrogen, on the health of aquatic life is of increasing concern. We exposed female American alligators to three concentrations of nitrate (0.7, 10 and 100mg/L NO 3 -N) for a duration of five weeks and five months from hatch. We assessed growth, plasma sex steroid and thyroid hormone concentrations, and transcription levels of key genes involved in steroidogenesis (StAR, 3β-HSD, and P450 scc ) and hepatic clearance (Cyp1a, Cyp3a). Exposure to 100mg/L NO 3 -N for both five weeks and five months resulted in significantly increased plasma testosterone (T) concentrations compared with alligators in the reference treatment. No differences in 17β-estradiol, progesterone, or thyroid hormones were observed, nor were there differences in alligator weight or the mRNA abundance of steroidogenic or hepatic genes. Plasma and urinary nitrate concentrations increased with increasing nitrate treatment levels, although relative plasma concentrations of nitrate were significantly lower in five month, versus five week old animals, possibly due to improved kidney function in older animals. These results indicate that environmentally relevant concentrations of nitrate can increase circulating concentrations of T in young female alligators. Copyright © 2016 Elsevier Inc. All rights reserved.
Glaser, RL; Dimitrakakis, C; Messenger, AG
2012-01-01
Background Androgens are thought to have an adverse effect on female scalp hair growth. However, our clinical experience of androgen replacement therapy in women with androgen deficiency, in which hair loss was seldom reported, led us to question this concept. Objectives To evaluate the effect of subcutaneous testosterone therapy on scalp hair growth in female patients. Methods A total of 285 women, treated for a minimum of 1 year with subcutaneous testosterone implants for symptoms of androgen deficiency, were asked to complete a survey that included questions on scalp and facial hair. Age, body mass index (BMI) and serum testosterone levels were examined. Results Out of the 285 patients, 76 (27%) reported hair thinning prior to treatment; 48 of these patients (63%) reported hair regrowth on testosterone therapy (responders). Nonresponders (i.e. no reported hair regrowth on therapy) had significantly higher BMIs than responders (P = 0·05). Baseline serum testosterone levels were significantly lower in women reporting hair loss prior to therapy than in those who did not (P = 0·0001). There was no significant difference in serum testosterone levels, measured 4 weeks after testosterone implantation, between responders and nonresponders. No patient in this cohort reported scalp hair loss on testosterone therapy. A total of 262 women (92%) reported some increase in facial hair growth. Conclusions Subcutaneous testosterone therapy was found to have a beneficial effect on scalp hair growth in female patients treated for symptoms of androgen deficiency. We propose this is due to an anabolic effect of testosterone on hair growth. The fact that no subject complained of hair loss as a result of treatment casts doubt on the presumed role of testosterone in driving female scalp hair loss. These results need to be confirmed by formal measurements of hair growth. PMID:21967243
Three and six grams supplementation of d-aspartic acid in resistance trained men.
Melville, Geoffrey W; Siegler, Jason C; Marshall, Paul Wm
2015-01-01
Although abundant research has investigated the hormonal effects of d-aspartic acid in rat models, to date there is limited research on humans. Previous research has demonstrated increased total testosterone levels in sedentary men and no significant changes in hormonal levels in resistance trained men. It was hypothesised that a higher dosage may be required for experienced lifters, thus this study investigated the effects of two different dosages of d-aspartic acid on basal hormonal levels in resistance trained men and explored responsiveness to d-aspartic acid based on initial testosterone levels. Twenty-four males, with a minimum of two years' experience in resistance training, (age, 24.5 ± 3.2 y; training experience, 3.4 ± 1.4 y; height, 178.5 ± 6.5 cm; weight, 84.7 ± 7.2 kg; bench press 1-RM, 105.3 ± 15.2 kg) were randomised into one of three groups: 6 g.d(-1) plain flour (D0); 3 g.d(-1) of d-aspartic acid (D3); and 6 g.d(-1) of d-aspartic acid (D6). Participants performed a two-week washout period, training four days per week. This continued through the experimental period (14 days), with participants consuming the supplement in the morning. Serum was analysed for levels of testosterone, estradiol, sex hormone binding globulin, albumin and free testosterone was determined by calculation. D-aspartic acid supplementation revealed no main effect for group in: estradiol; sex-hormone-binding-globulin; and albumin. Total testosterone was significantly reduced in D6 (P = 0.03). Analysis of free testosterone showed that D6 was significantly reduced as compared to D0 (P = 0.005), but not significantly different to D3. Analysis did not reveal any significant differences between D3 and D0. No significant correlation between initial total testosterone levels and responsiveness to d-aspartic acid was observed (r = 0.10, P = 0.70). The present study demonstrated that a daily dose of six grams of d-aspartic acid decreased levels of total testosterone and free testosterone (D6), without any concurrent change in other hormones measured. Three grams of d-aspartic acid had no significant effect on either testosterone markers. It is currently unknown what effect this reduction in testosterone will have on strength and hypertrophy gains.
van Honk, Jack; Schutter, Dennis J L G
2007-08-01
Elevated levels of testosterone have repeatedly been associated with antisocial behavior, but the psychobiological mechanisms underlying this effect are unknown. However, testosterone is evidently capable of altering the processing of facial threat, and facial signals of fear and anger serve sociality through their higher-level empathy-provoking and socially corrective properties. We investigated the hypothesis that testosterone predisposes people to antisocial behavior by reducing conscious recognition of facial threat. In a within-subjects design, testosterone (0.5 mg) or placebo was administered to 16 female volunteers. Afterward, a task with morphed stimuli indexed their sensitivity for consciously recognizing the facial expressions of threat (disgust, fear, and anger) and nonthreat (surprise, sadness, and happiness). Testosterone induced a significant reduction in the conscious recognition of facial threat overall. Separate analyses for the three categories of threat faces indicated that this effect was reliable for angry facial expressions exclusively. This testosterone-induced impairment in the conscious detection of the socially corrective facial signal of anger may predispose individuals to antisocial behavior.
Di Fiore, Maria M; Lamanna, Claudia; Assisi, Loredana; Botte, Virgilio
2008-07-04
D-Aspartic acid (D-Asp) and nitric oxide (NO) play an important role in tuning testosterone production in the gonads of male vertebrates. In particular, D-Asp promotes either the synthesis or the release of testosterone, whereas NO inhibits it. In this study, we have investigated for the first time in birds the putative effects of D-Asp and NO on testicular testosterone production in relation to two phases of the reproductive cycle of the adult captive wild-strain mallard (Anas platyrhynchos) drake. It is a typical seasonal breeder and its cycle consists of a short reproductive period (RP) in the spring (April-May) and a non reproductive period (NRP) in the summer (July), a time when the gonads are quiescent. The presence and the localization of D-Asp and NO in the testis and the trends of D-Asp, NO and testosterone levels were assessed during the main phases of the bird's reproductive cycle. Furthermore, in vitro experiments revealed the direct effect of exogenously administered D-Asp and NO on testosterone steroidogenesis. By using immunohistochemical (IHC) techniques, we studied the presence and the distributional pattern of D-Asp and NO in the testes of RP and NRP drakes. D-Asp levels were evaluated by an enzymatic method, whereas NO content, via nitrite, was assessed using biochemical measurements. Finally, immunoenzymatic techniques determined testicular testosterone levels. IHC analyses revealed the presence of D-Asp and NO in Leydig cells. The distributional pattern of both molecules was in some way correlated to the steroidogenic pathway, which is involved in autocrine testosterone production. Indeed, whereas NO was present only during the NRP, D-Asp was almost exclusively present during the RP. Consistently, the high testosterone testicular content occurring during RP was coupled to a high D-Asp level and a low NO content in the gonad. By contrast, in sexually inactive drakes (NRP), the low testosterone content in the gonad was coupled to a low D-Asp content and to a relatively high NO level. Consequently, to determine the exogenous effects of the two amino acids on testosterone synthesis, we carried out in vitro experiments using testis sections deriving from both the RP and NRP. When testis slices were incubated for 60 or 120 min with D-Asp, testosterone was enhanced, whereas in the presence of L-Arg, a precursor of NO, it was inhibited. Our results provide new insights into the involvement of D-Asp and NO in testicular testosterone production in the adult captive wild-strain mallard drake. The localization of these two molecules in the Leydig cells in different periods of the reproductive cycle demonstrates that they play a potential role in regulating local testosterone production.
Dopamine mediates testosterone-induced social reward in male Syrian hamsters.
Bell, Margaret R; Sisk, Cheryl L
2013-03-01
Adolescent maturation of responses to social stimuli is essential for adult-typical sociosexual behavior. Naturally occurring developmental changes in male Syrian hamster responses to a salient social cue, female hamster vaginal secretions (VS), provide a good model system for investigating neuroendocrine mechanisms of adolescent change in social reward. Sexually naïve adult, but not juvenile, males show a conditioned place preference (CPP) to VS, indicating that VS is not rewarding before puberty. In this series of experiments, the authors examined the roles of testosterone and dopamine receptor activation in mediating the adolescent gain in positive valence of VS. Experiment 1 showed that testosterone replacement is necessary for gonadectomized adult hamsters to form a CPP to VS. Experiment 2 showed that testosterone treatment is sufficient for juvenile hamsters to form a CPP to VS, and that the dopamine receptor antagonist haloperidol blocks formation of a CPP to VS in these animals. Experiments 3 and 4 demonstrated that the disruption of VS CPP with low doses of haloperidol is the result of a reduction in the attractive properties of VS and not attributable to aversive properties of haloperidol. Together, these studies demonstrate that the unconditioned rewarding properties of a social cue necessary for successful adult sociosexual interactions come about as the result of the pubertal increase in circulating testosterone in male hamsters. Furthermore, this social reward can be prevented by dopamine receptor antagonism, indicating that hypothalamic and/or mesocorticolimbic dopaminergic circuits are targets for hormonal activation of social reward.
Ghanim, Husam; Dhindsa, Sandeep; Abuaysheh, Sanaa; Batra, Manav; Kuhadiya, Nitesh D; Makdissi, Antoine; Chaudhuri, Ajay; Dandona, Paresh
2018-03-01
One-third of males with type 2 diabetes (T2DM) have hypogonadism, characterized by low total and free testosterone concentrations. We hypothesized that this condition is associated with a compensatory increase in the expression of androgen receptors (AR) and that testosterone replacement reverses these changes. We also measured estrogen receptor and aromatase expression. This is a randomized double-blind placebo-controlled trial. Thirty-two hypogonadal and 32 eugonadal men with T2DM were recruited. Hypogonadal men were randomized to receive intramuscular testosterone or saline every 2 weeks for 22 weeks. We measured AR, ERα and aromatase expression in peripheral blood mononuclear cells (MNC), adipose tissue and skeletal muscle in hypogonadal and eugonadal males with T2DM at baseline and after 22 weeks of treatment in those with hypogonadism. The mRNA expression of AR, ERα (ESR1) and aromatase in adipose tissue from hypogonadal men was significantly lower as compared to eugonadal men, and it increased significantly to levels comparable to those in eugonadal patients with T2DM following testosterone treatment. AR mRNA expression was also significantly lower in MNC from hypogonadal patients compared to eugonadal T2DM patients. Testosterone administration in hypogonadal patients also restored AR mRNA and nuclear extract protein levels from MNC to that in eugonadal patients. In the skeletal muscle, AR mRNA and protein expression are lower in men with hypogonadism. Testosterone treatment restored AR expression levels to that comparable to levels in eugonadal men. We conclude that, contrary to our hypothesis, the expression of AR, ERα and aromatase is significantly diminished in hypogonadal men as compared to eugonadal men with type 2 diabetes. Following testosterone replacement, there is a reversal of these deficits. © 2018 European Society of Endocrinology.
Testosterone, DHEA and DHEA-S in patients with schizophrenia: A systematic review and meta-analysis.
Misiak, Błażej; Frydecka, Dorota; Loska, Olga; Moustafa, Ahmed A; Samochowiec, Jerzy; Kasznia, Justyna; Stańczykiewicz, Bartłomiej
2018-03-01
Neuroactive steroids, including testosterone, dehydroepiandrosterone (DHEA) and its sulfate (DHEA-S) might play an important role in the pathophysiology of schizophrenia. Therefore, we performed a systematic review and meta-analysis of studies comparing the levels of testosterone, DHEA and DHEA-S in patients with schizophrenia and healthy controls. We searched electronic databases from their inception until Oct 29, 2017. Effect size (ES) estimates were calculated as Hedges' g. Data analysis was performed using random-effects models. Our analysis included 34 eligible studies, representing 1742 patients and 1604 controls. Main analysis revealed elevated DHEA-S levels in the whole group of patients (ES = 0.75, 95%CI: 0.23-1.28, p = 0.005). In subgroup analyses, patients with first-episode psychosis (FEP) had significantly higher levels of free testosterone (ES = 1.21, 95%CI: 0.30-2.12, p = 0.009) and DHEA-S (ES = 1.19, 95%CI: 0.66-1.71, p < 0.001). Acutely relapsed schizophrenia patients presented significantly higher levels of total testosterone (ES = 0.50, 95%CI: 0.21-0.70, p < 0.001). Total testosterone levels were also elevated in stable multi-episode schizophrenia (sMES) females (ES = 0.56, 95%CI: 0.33-0.80, p < 0.001) and reduced in sMES males (ES = -0.62, 95%CI: -1.07 to 0.18, p = 0.006). Increased levels of biologically active, free testosterone and DHEA-S in FEP suggest that these alterations might appear as a response to stress that becomes blunted during subsequent exacerbations of schizophrenia. Differential changes in total testosterone levels in male and female sMES patients might represent medication effects related to prolactin-releasing effects of antipsychotics. Copyright © 2018 Elsevier Ltd. All rights reserved.
Cardarelli, Roberto; Singh, Meharvan; Meyer, Jason; Balyakina, Elizabeth; Perez, Oscar; King, Michael
2014-07-01
Hypogonadism is highly prevalent in men older than 45 years and is associated with an increased risk of chronic diseases, including obesity, metabolic syndrome, diabetes, and cardiovascular disease. The objective of this study was to determine whether lifestyle factors such as smoking, diet, and exercise are associated with reduced testosterone levels. In this cross-sectional study, 147 men older than 44 years were recruited from a collaborative network of primary care clinics in the Dallas/Fort Worth, Texas, metropolitan area. Free testosterone levels were measured in plasma samples via an enzyme-linked immunosorbent assay-based method, and analyzed by simple and multiple linear regression in relationship to age, race/ethnicity, smoking, diet, exercise, obesity, diabetes, hypertension, and dyslipidemia. The participants had a mean free testosterone level of 3.1 ng/mL (standard deviation [SD] = 1.5) and mean age of 56.8 years (SD = 7.9). In simple regression analysis, free testosterone levels were associated with increased age (β = -0.04; P = .02), diet (β = -0.49; P = .05), diabetes (β = -0.9; P = .003), and hypertension (β = -0.55; P = .03) but not with race/ethnicity, smoking, exercise, obesity, or dyslipidemia. In multiple regression analysis, free testosterone values were significantly associated only with age (β = -0.05; P = .01) and diet (β = -0.72; P = .01). This study implicates diet, in addition to advanced age as a possible risk factor in the development of reduced testosterone levels. © The Author(s) 2014.
Provider and Site-Level Determinants of Testosterone Prescribing in the Veterans Healthcare System.
Jasuja, Guneet K; Bhasin, Shalender; Rose, Adam J; Reisman, Joel I; Hanlon, Joseph T; Miller, Donald R; Morreale, Anthony P; Pogach, Leonard M; Cunningham, Francesca E; Park, Angela; Wiener, Renda S; Gifford, Allen L; Berlowitz, Dan R
2017-09-01
Testosterone prescribing rates have increased substantially in the past decade. However, little is known about the context within which such prescriptions occur. We evaluated provider- and site-level determinants of receipt of testosterone and of guideline-concordant testosterone prescribing. This study was cross-sectional in design. This study was conducted at the Veterans Health Administration (VA). Study participants were a national cohort of male patients who had received at least one outpatient prescription within the VA during fiscal year (FY) 2008 to FY 2012. A total of 38,648 providers and 130 stations were associated with these patients. This study measured receipt of testosterone and guideline-concordant testosterone prescribing. Providers ranging in age from 31 to 60 years, with less experience in the VA [all adjusted odds ratio (AOR), <2; P < 0.01] and credentialed as medical doctors in endocrinology (AOR, 3.88; P < 0.01) and urology (AOR, 1.48; P < 0.01) were more likely to prescribe testosterone compared with older providers, providers of longer VA tenure, and primary care providers, respectively. Sites located in the West compared with the Northeast [AOR, 1.75; 95% confidence interval (CI), 1.45-2.11] and care received at a community-based outpatient clinic compared with a medical center (AOR, 1.22; 95% CI, 1.20-1.24) also predicted testosterone use. Although they were more likely to prescribe testosterone, endocrinologists were also more likely to obtain an appropriate workup before prescribing compared with primary care providers (AOR, 2.14; 95% CI, 1.54-2.97). Our results highlight the opportunity to intervene at both the provider and the site levels to improve testosterone prescribing. This study also provides a useful example of how to examine contributions to prescribing variation at different levels of the health care system. Copyright © 2017 Endocrine Society
Goncharov, Alexey; Rej, Robert; Negoita, Serban; Schymura, Maria; Santiago-Rivera, Azara; Morse, Gayle; Carpenter, David O.
2009-01-01
Background Polychlorinated biphenyls (PCBs) and chlorinated pesticides are endocrine disruptors, altering both thyroid and estrogen hormonal systems. Less is known of action on androgenic systems. Objective We studied the relationship between serum concentrations of testosterone in relation to levels of PCBs and three chlorinated pesticides in an adult Native American (Mohawk) population. Methods We collected fasting serum samples from 703 adult Mohawks (257 men and 436 women) and analyzed samples for 101 PCB congeners, hexachlorobenzene (HCB), dichlorodiphenyldichloroethylene (DDE), and mirex, as well as testosterone, cholesterol, and triglycerides. The associations between testosterone and tertiles of serum organochlorine levels (both wet weight and lipid adjusted) were assessed using a logistic regression model while controlling for age, body mass index (BMI), and other analytes, with the lowest tertile being considered the referent. Males and females were considered separately. Results Testosterone concentrations in males were inversely correlated with total PCB concentration, whether using wet-weight or lipid-adjusted values. The odds ratio (OR) of having a testosterone concentration above the median was 0.17 [95% confidence interval (CI), 0.05–0.69] for total wet-weight PCBs (highest vs. lowest tertile) after adjustment for age, BMI, total serum lipids, and three pesticides. The OR for lipid-adjusted total PCB concentration was 0.23 (95% CI, 0.06–0.78) after adjustment for other analytes. Testosterone levels were significantly and inversely related to concentrations of PCBs 74, 99, 153, and 206, but not PCBs 52, 105, 118, 138, 170, 180, 201, or 203. Testosterone concentrations in females are much lower than in males, and not significantly related to serum PCBs. HCB, DDE, and mirex were not associated with testosterone concentration in either men or women. Conclusions Elevation in serum PCB levels is associated with a lower concentration of serum testosterone in Native American men. PMID:19750113
Montgomery, Tracy M; Pendleton, Erika L; Smith, Jennifer E
2018-05-02
Although cooperation represents a long-standing evolutionary puzzle, field studies on social carnivores have contributed greatly to our understanding of the selective forces favoring cooperative breeding. Despite these insights, our grasp of the proximate mechanisms facilitating cooperation in carnivores remains surprisingly limited. Here we provide an overview of our current knowledge of the endocrine mechanisms mediating cooperative breeding in terrestrial species belonging to the mammalian order Carnivora. We focus primarily on aspects of reproductive suppression and alloparental care. We find few studies on the topic, with some of the best studies focusing on the behavioral endocrinology of cooperative breeding in canids (dogs) and herpestids (mongooses). Overall, these studies suggest that breeding females typically have higher circulating levels of estrogen, luteinizing hormone, progesterone, and prolactin than do non-breeding adult females. We also find that among males, testosterone levels are often elevated in breeders compared to non-breeding adult males. The effect of glucocorticoids on reproductive suppression in carnivores appears to be sex-specific: breeding males typically have higher glucocorticoid levels than their non-breeding subordinates, but there is no clear pattern for breeding females. Finally, elevated levels of prolactin and oxytocin are consistently associated with alloparental care in cooperatively breeding carnivores, whereas testosterone and glucocorticoids are often lower in individuals who participate in alloparenting. Taken together, our synthesis elucidates striking gaps in our knowledge of carnivore physiology, especially the endocrine mechanisms promoting alloparental care, and we identify important areas for future research. Copyright © 2017 Elsevier Inc. All rights reserved.
How do we love? Romantic love style in men is related to lower testosterone levels.
Babková Durdiaková, J; Celec, P; Koborová, I; Sedláčková, T; Minárik, G; Ostatníková, D
2017-09-22
Testosterone has been widely investigated in associations with many aspects of social interactions, emotions and behavior. No research has been conducted on its contribution to the variability of love styles in human. The aim of this paper was to uncover the possible relationship between not only the actual plasma testosterone levels, but also the prenatal testosterone level (expressed as 2D:4D ratio) and the sensitivity of androgen receptor and love typology in young healthy men. There are six love styles which are primary including Eros (passionate romantic love), Ludus (playful) and Storge (friendly) and secondary love consisting of Mania (obsessive), Pragma (practical realistic) and Agape (altruistic). Our results pointed out that low testosterone concentrations are associated with higher score for Eros, Ludus, Pragma, Mania love style. No significant association was proved for other tested parameters of androgenicity (2D:4D, sensitivity of androgen receptor) and love style after correction was applied. Different attitudes and behavior in relationships do have a biological foundation related to endogenous testosterone levels in plasma. Future studies should address questions about the family and social background of participants to differentiate here between moral rules or/and social-conventional rules.
Alabi, A S; Omotosho, G O; Tagoe, C N B; Akinola, O B; Enaibe, B U
2017-06-30
This study was aimed at determining the effects of the unripe fruit of Musa paradisiaca on the testis andtestosterone levels in male Wistar rats. The animals were grouped into three, comprising a control, and 2 treatment groupsadministered with different doses (500 mg/kg and 1000 mg/kg) daily of the fruit flour over 28 days. Histochemical evaluationof the testes was done using Haematoxylin and Eosin, Periodic acid Schiff's (PAS) and Feulgen staining techniques, whilethe serum and homogenised testicular tissue were evaluated for testosterone levels using Accu-Bind ELISA Kit. The testisof the treated groups showed more rapidly dividing cells and more population of sperm cells compared to the control group,and also showed more positivity for Feulgen staining and PAS reaction. Both serum and testicular testosterone levels werehowever reduced. Serum testosterone was significantly lowered in the animals given the low dose (0.67 ± 0.03 ng/ml),compared to those given high dose (0.85 ± 0.02 ng/ml) and the control animals (1.88 ± 0.15 ng/ml) (p < 0.05). Changes intesticular testosterone were not statistically significant. The study suggests that M. paradisiaca fruit has reproductiveenhancing potential when consumed moderately, but this benefit may not be related to testosterone levels.
Plasma Testosterone and the Course of Major Depressive Disorder in Older Men and Women.
Giltay, Erik J; van der Mast, Roos C; Lauwen, Esther; Heijboer, Annemieke C; de Waal, Margot W M; Comijs, Hannie C
2017-04-01
To investigate associations between testosterone levels and major depressive disorder (MDD) in older men and women. In a cross-sectional, 2-year prospective analyses within the Netherlands Study on Depression in Older persons cohort study, 469 participants comprised 350 patients with MDD and 119 nondepressed participants in the comparison group (mean age 70.5 ± 7.3 years; 166 [35.4%] men). MDD was assessed by the Composite International Diagnostic Interview. Baseline plasma total testosterone and sex hormone binding globulin (SHBG) were assessed to calculate free testosterone. The Inventory of Depressive Symptomatology was assessed every 6 months. Whereas SHBG levels did not differ between the depressed/nondepressed groups (F(1,149) = 0.075, p = 0.78), men with MDD had lower mean total and free testosterone levels than the comparison group in the multivariate adjusted analyses (F(1,150) = 7.249, p = 0.008, Cohen's d = 0.51; and F(1,149) = 8.548, p = 0.004 Cohen's d = 0.55, respectively). This could be ascribed to lower testosterone in men with "pure" MDD and not in men with MDD and comorbid anxiety. Nine men (5.4%) had a total testosterone level < 8 nmol/L, of whom 8 suffered from MDD. In women, hormone levels showed no significant difference between the groups. In men (using all five measurement points during follow-up) baseline free testosterone was inversely associated with depression severity in the adjusted analyses (β = -0.15, t(151) = -2.15, p = 0.03). Testosterone levels were lower in men with MDD compared with healthy men after adjustment for confounders, such as body mass index. No significant associations were found in women. Copyright © 2017 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.
Testosterone therapy in microphallic hypospadias: topical or parenteral?
Chalapathi, G; Rao, K L N; Chowdhary, S K; Narasimhan, K L; Samujh, Ram; Mahajan, J K
2003-02-01
Local or systemic application of testosterone is reported to stimulate penile growth. Intramuscular testosterone has been found to be effective in 50% of patients; however, variable results have been reported with topical testosterone. The current study is an attempt to compare the efficacy of intramuscular versus topical testosterone application. A total of 26 consecutive patients with hypospadias and small penis (<2SD for given age) were studied prospectively. These patients were recruited alternately into group A or group B. Each group consisted of 13 patients. In group A, penile growth was accomplished by topical application of testosterone (Testoviron, oily solution containing testosterone propionate, 25 mg, and testosterone enanthate, 110 mg, equivalent to about 100 mg of testosterone, Schering, Germany) with a dose of 2 mg/kg/wk, for 3 weeks. While in group B, testosterone (same preparation as above) was administered by intramuscular injection weekly for 3 consecutive weeks. Penile length, diameter, and secondary effects were recorded before, during, and 3 weeks after the therapy by a single observer. Significant penile growth (P <.01) was noticed in both the groups of patients when compared with pretherapy with maximum response observed during the third week of therapy (reaching from an average pretherapy length of 2.0 cm and 1.8 cm to 3.18 cm and 3.11 cm posttherapy in group A and B patients, respectively). Seven patients in each group had growth of at least 50% compared with the initial size. The basal serum testosterone was within the normal range in both the groups. During therapy the serum testosterone was elevated above the basal level in all patients, but within the normal range except in 2 patients of group A. In these 2 children the serum testosterone level crossed the normal range. Linear growth did not alter significantly for the chronological age. Two patients of group A went on to have pubic hair, one of them had elevated testosterone level above the normal range. There was a surge in serum testosterone in all children, although significant penile enlargement was observed in 60% children in group A and 75% in group B. Although the desired therapeutic effect of testosterone was achieved in both the groups, this study failed to show any significant difference between the 2 routes of administration. However, in group A, (topical) serum testosterone crossed the normal range in 15% of patients and was associated with significant reversible side effects. Copyright 2003, Elsevier Science (USA). All rights reserved.
Richard, Justin T; Robeck, Todd R; Osborn, Steven D; Naples, Lisa; McDermott, Alexa; LaForge, Robert; Romano, Tracy A; Sartini, Becky L
2017-05-15
Steroid hormone analysis in blow (respiratory vapor) may provide a minimally invasive way to assess the reproductive status of wild cetaceans. Biological validation of the method is needed to allow for the interpretation of hormone measurements in blow samples. Utilizing samples collected from trained belugas (Delphinapterus leucas, n=20), enzyme immunoassays for testosterone and progesterone were validated for use with beluga blow samples. Testosterone concentrations in 40 matched blood and blow samples collected from 4 male belugas demonstrated a positive correlation (R 2 =0.52, p<0.0001). Progesterone concentrations in 64 matching blood and blow samples from 11 females were also positively correlated (R 2 =0.60, p<0.0001). Testosterone concentrations (mean±SD) in blow samples collected from adult males (119.3±14.2pg/ml) were higher (p<0.01) than that of a juvenile male (<8years) (59.4±6.5pg/ml) or female belugas (54.1±25.7pg/ml). Among adult males, testosterone concentrations in blow demonstrated a seasonal pattern of secretion, with peak secretion occurring during the breeding season (February-April, 136.95±33.8pg/ml). Progesterone concentrations in blow varied by reproductive status; pregnant females (410.6±87.8pg/ml) and females in the luteal phase of the estrous cycle (339.5±51.0pg/ml) had higher (p<0.0001) blow progesterone concentrations than non-pregnant females without a corpus luteum (242.5±27.3pg/ml). Results indicate that blow sample analysis can be used to detect variation in reproductive states associated with large differences in circulating testosterone or progesterone in belugas. Copyright © 2016 Elsevier Inc. All rights reserved.
Premenopausal circulating androgens and risk of endometrial cancer: Results of a prospective study
Clendenen, Tess V.; Hertzmark, Kathryn; Koenig, Karen L.; Lundin, Eva; Rinaldi, Sabina; Johnson, Theron; Krogh, Vittorio; Hallmans, Göran; Idahl, Annika; Lukanova, Annekatrin; Zeleniuch-Jacquotte, Anne
2016-01-01
Endometrial cancer risk is increased by estrogens unopposed by progesterone. In premenopausal women, androgen excess is often associated with progesterone insufficiency, suggesting that premenopausal androgen concentrations may be associated with risk. In a case-control study nested within three cohorts, we assessed the relationship between premenopausal androgens and risk of endometrial cancer (161 cases and 303 controls matched on age and date of blood donation). Testosterone, DHEAS, androstenedione, and SHBG were measured in serum or plasma. Free testosterone was calculated from testosterone and SHBG. We observed trends of increasing risk across tertiles of testosterone (ORT3-T1: 1.59, 95%CI: 0.96, 2.64, p=0.08) and free testosterone (ORT3-T1: 1.76, 95%CI: 1.01, 3.07, p=0.047), which were not statistically significant after adjustment for body mass index (BMI). There was no association for DHEAS, androstenedione, or SHBG. There were significant interactions by age at diagnosis (<55 years, n=51 cases; ≥55 years, n=110 cases). Among women who were ≥55 years of age (predominantly postmenopausal) at diagnosis, the BMI-adjusted OR was 2.08 (95%CI: 1.25, 3.44, p=0.005) for a doubling in testosterone and 1.55 (95%CI: 1.04, 2.31, p=0.049) for a doubling in free testoterone. There was no association among women aged <55 years at diagnosis, consistent with the only other prospective study to date. If pre- and post-menopausal concentrations of androgens are correlated, our observation of an association of premenopausal androgens with risk among women aged ≥55 years at diagnosis could be due to the effect on the endometrium of postmenopausal androgen-derived estrogens in the absence of progesterone, which is no longer secreted. PMID:26925952
Ronay, Richard; van der Meij, Leander; Oostrom, Janneke K.; Pollet, Thomas V.
2018-01-01
Using a recently developed alternative assay procedure to measure hormone levels from hair samples, we examined the relationships between testosterone, cortisol, 2D:4D ratio, overconfidence and risk taking. A total of 162 (53 male) participants provided a 3 cm sample of hair, a scanned image of their right and left hands from which we determined 2D:4D ratios, and completed measures of overconfidence and behavioral risk taking. While our sample size for males was less than ideal, our results revealed no evidence for a relationship between hair testosterone concentrations, 2D:4D ratios and risk taking. No relationships with overconfidence emerged. Partially consistent with the Dual Hormone Hypothesis, we did find evidence for the interacting effect of testosterone and cortisol on risk taking but only in men. Hair testosterone concentrations were positively related to risk taking when levels of hair cortisol concentrations were low, in men. Our results lend support to the suggestion that endogenous testosterone and 2D:4D ratio are unrelated and might then exert diverging activating vs. organizing effects on behavior. Comparing our results to those reported in the existing literature we speculate that behavioral correlates of testosterone such as direct effects on risk taking may be more sensitive to state-based fluctuations than baseline levels of testosterone. PMID:29556180
When is a varicocele repair indicated: the dilemma of hypogonadism and erectile dysfunction?
Dabaja, Ali A; Goldstein, Marc
2016-01-01
In the past, the indications for varicocelectomy are primarily for infertility with abnormal semen parameters, testicular hypotrophy/atrophy in adolescents, and/or pain. The surgical treatment of varicocele for hypogonadism is controversial and debated. Recently, multiple reports in the literature have suggested that varicocele is associated with hypogonadism and varicocele repair can increase testosterone levels. Men with hypogonadal symptoms should have at least two serum testosterone levels. Microsurgical varicocelectomy may be beneficial for men with clinically palpable varicoceles with documented hypogonadism. In this review, we summarize the most recent literature linking varicocele to hypogonadism and sexual dysfunction and the impact of repair on serum testosterone levels. We performed a search of the published English literature. The key words used were "varicocele and hypogonadism" and "varicocele surgery and testosterone." We included published studies after 1998. We, also, evaluated the effect of surgery on the changes in the serum testosterone level regardless of the indication for the varicocele repair.
Donham, R.S.
1979-01-01
Comparisons between 'wild'and 'game farm' mallards (Anas platyrhynchos) were made to assess the differences in the temporal changes of plasma hormones. Seasonal variation in the levels of immunoreactive luteinizing hormone (LH), testosterone, 5 -dihydrotestosterone (DHT), estrone, estradiol-17i?? and progesterone were measured in male and female mallards. In all birds there was a vernal increase in the concentrations of LH and testosterone in plasma which were correlated with the development of the testes and ovaries prior to and during the nesting season. The concentrations of estrogens in the plasma of the females were, in general, slightly higher during the nesting season but were much lower than the levels of testosterone. The highest levels of LH and testosterone in the females coincided precisely with the period of egg laying which occurred approximately one month earlier in game farm females than in wild females. The concentrations of LH and testosterone in the plasma of females decreased rapidly during incubation. In wild males, the decline in levels of these hormones temporally coincided with that of females. In contrast, plasma levels of LH and testosterone of males of the game farm stock remained elevated after the beginning of incubation in females to which they were paired. On the basis of these results and an examination of the literature, it appears that domestication results in: 1) increased reproductive potential through earlier initiation of nesting and by delay of the termination of reproduction until later in the summer; and 2) a decrease in the synchronization of the hormonal events supporting reproduction between the male and female of a pair. Testicular weights and plasma levels of testosterone become higher in game farm and domestic males than in the wild stock but levels of LH are similar.
Shangguan, Fangfang; Shi, Jiannong
2009-08-01
Sex hormone such as testosterone was recently recognized as an important contributor of spatial cognition and intelligence during development, but the relationship between puberty timing and intelligence especially in children is largely unknown. Here in this study, we investigated the potential relationship between the level of sex hormones in saliva and fluid intelligence in 8- to 12-year-old Chinese boys. Fluid intelligence was measured by the Cattell's Culture Fair Intelligence Test. 1600 children aged 8-12 years were included in the Cattell's Culture Fair Intelligence Test and saliva samples were collected thereafter from 166 boys with normal intelligence distribution, composed of 49, 54 and 63 boys in 8-, 10- and 12-year-old group respectively. The level of salivary testosterone and estradiol was measured with enzyme-immunoassay technique. Data of BMI and age were collected. The relationship between the level of salivary sex hormones and fluid intelligence was analysed by correlation test. There was no significant correlation between salivary testosterone level and fluid intelligence in 8-year-old boys, whereas there was a significant positive correlation in 10-year-old boys and a significant negative correlation in 12-year-old boys between those two variable. To verify the correlation, we performed stepwise multivariate linear regression and discriminant analysis, with both the age and BMI of the boys and their parents, and salivary estradiol level considered. The results showed that the level of testosterone and intelligence was correlated, and the correlation was much stronger when the level of salivary testosterone was higher than 14 pg/ml. In summary, the study suggests that the relationship of testosterone and intelligence varies from late childhood to early adolescence, and the puberty timing is closely related with fluid intelligence.
Burney, Basil O; Hayes, Teresa G; Smiechowska, Joanna; Cardwell, Gina; Papusha, Victor; Bhargava, Peeyush; Konda, Bhavana; Auchus, Richard J; Garcia, Jose M
2012-05-01
Male cancer patients suffer from fatigue, sexual dysfunction, and decreased functional performance and muscle mass. These symptoms are seen in men with hypogonadism and/or inflammatory conditions. However, the relative contribution of testosterone and inflammation to symptom burden in cancer has not been well-established. The aim of this study was to measure testosterone levels in male cancer patients and determine the relationship between testosterone, inflammation, and symptom burden. This cross-sectional study enrolled patients from a tertiary-care center. SUBJECTS/OUTCOME MEASURES: Subjects included males with cancer-cachexia (CC; n = 45) and cancer without cachexia (CNC; n = 50), as well as noncancer controls (CO; n = 45). Total testosterone (TT), bioavailable testosterone, C-reactive protein (CRP), and IL-6 were measured in plasma. Functional performance was assessed by the ECOG (Eastern Cooperative Oncology Group) and KPS (Karnofsky Performance Scales), and sexual function was assessed by the IIEF (International Index of Erectile Function). Low testosterone levels were seen in more than 70% of CC cases. TT was lower in CC compared to CNC (P < 0.05). Also, CC had lower bioavailable testosterone, grip strength, IIEF scores, appendicular lean body mass, and fat mass and higher IL-6 and CRP compared to controls (P ≤ 0.05). ECOG and KPS were lower in CC and CNC compared to controls (P ≤ 0.05). On multiple regression analysis, TT, albumin, and CRP predicted symptoms differentially in cancer patients. CC patients have higher inflammation and lower testosterone, grip strength, functional status, erectile function, fat mass, and appendicular lean body mass. Inflammation, TT, and albumin are associated with heavier symptom burden in this population. Interventional trials are needed to determine whether testosterone replacement and/or antiinflammatory agents benefit cancer patients.
Testosterone related to age and life-history stages in male baboons and geladas
Beehner, Jacinta C.; Gesquiere, Laurence; Seyfarth, Robert M.; Cheney, Dorothy L.; Alberts, Susan C.; Altmann, Jeanne
2013-01-01
Despite significant advances in our knowledge of how testosterone mediates life-history trade-offs, this research has primarily focused on seasonal species. We know comparatively little about the relationship between testosterone and life-history stages for non-seasonally breeding species. Here we examine testosterone profiles across the lifespan of males from three non-seasonally breeding primates: yellow baboons (Papio cynocephalus or P. hamadryas cynocephalus), chacma baboons (Papio ursinus or P. h. ursinus), and geladas (Theropithecus gelada). First, we predict that testosterone profiles will track the reproductive profiles of each taxon across their respective breeding years. Second, we evaluate age-related changes in testosterone to determine whether several life-history transitions are associated with these changes. Subjects include males (>2.5 years) from wild populations of each taxon from whom we had fecal samples for hormone determination. Although testosterone profiles across species were broadly similar, considerable variability was found in the timing of two major changes: (1) the attainment of adult levels of testosterone, and (2) the decline in testosterone after the period of maximum production. Attainment of adult testosterone levels was delayed by one year in chacmas compared with yellows and geladas. With respect to the decline in testosterone, geladas and chacmas exhibited a significant drop after three years of maximum production, while yellows declined so gradually that no significant annual drop was ever detected. For both yellows and chacmas, increases in testosterone production preceded elevations in social dominance rank. We discuss these differences in the context of ecological and behavioral differences exhibited by these taxa. PMID:19712676
Estradiol to testosterone ratio in metabolic syndrome men aged started 40 years above
NASA Astrophysics Data System (ADS)
Kusuma, R.; Siregar, Y.; Mardianto
2018-03-01
Disruption of adipose tissue, an endocrine organ, could turn out into the so-called metabolic syndrome. Aging men with lowering testosterone were related to metabolic syndrome and excessive aromatase activity in adipose tissue would increase estradiol level. This study hypothesized that estradiol to testosterone ratio is increasedin aging, metabolic syndrome men. A total of 52 men were randomly recruited for this study. A blood samplewas drawn before 11.00 AM after 10 hoursof overnight fasting, then aliquot serum kept in -20°C pending the research. Subjects were divided evenly into the metabolic syndrome and nonmetabolicsyndrome group. The hormonal assaywas measured on the day of research. Then examined with student t-test. Estradiol level in metabolic syndrome group was increased, but insignificant differ to the other group. Testosterone level decreased and significantly different between groups. In conclusion, estradiol to testosterone ratio was increased in themetabolic syndrome group but insignificant.
Matsui, Futoshi; Koh, Eitetsu; Yamamoto, Kenrou; Sugimoto, Kazuhiro; Sin, Ho-Su; Maeda, Yuji; Honma, Seijiro; Namiki, Mikio
2009-01-01
It is well known that late-onset hypogonadism in males can cause a variety of symptoms, and the differential diagnosis is relatively difficult, including psychological disorders, stress, and mood disturbances. The level of serum cortisol can be measured to reflect a patient's level of stress. Salivary hormones facilitate the evaluation of physiological hormonal actions based on free hormone assay. For the simultaneous measurement of testosterone and cortisol levels in saliva, we validate a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay. Concerning accuracy and precision, the lower limit of quantification of salivary testosterone and cortisol were established as 5 and 10 pg/mL, respectively. Testosterone and cortisol in saliva is stable for 2 days, 14 days, and 28 days at room temperature, refrigeration and frozen, respectively. Freezing and thawing for 3 cycles and stimulation of salivation with gum chewing do not alter the measured values of testosterone and cortisol. Total, bioavailable, and free serum testosterone showed slight diurnal changes, but total and bioavailable serum cortisol showed marked diurnal changes. Salivary testosterone levels negatively correlate with age, regardless of the time of saliva collection (r=0.64, p<0.05). However, there is no relationship between salivary cortisol and age (r=0033, p>0.05). LC-MS/MS allows rapid, simultaneous, sensitive, and accurate quantification of testosterone and cortisol in saliva for the diagnosis late-onset hypogonadism or other hormone related disease.
YANG, BI-CHENG; JIN, LI-LI; YANG, YI-FANG; LI, KUN; PENG, DAN-MING
2014-01-01
Benign prostatic hyperplasia (BPH) can lead to lower urinary tract symptoms. Rape pollen is an apicultural product that is composed of nutritionally valuable and biologically active substances. The aim of the present study was to investigate the protective effect of rape pollen supercritical CO2 fluid extract (SFE-CO2) in BPH development using a testosterone-induced BPH rat model. BPH was induced in the experimental groups by daily subcutaneous injections of testosterone for a period of 30 days. Rape pollen SFE-CO2 was administered daily by oral gavage concurrently with the testosterone injections. Animals were sacrificed at the scheduled termination and the prostates were weighed and subjected to histopathological examination. Testosterone, dihydrotestosterone (DHT), 5α-reductase and cyclooxygenase-2 (COX-2) levels were also measured. BPH-induced animals exhibited an increase in prostate weight with increased testosterone, DHT, 5α-reductase and COX-2 expression levels. However, rape pollen SFE-CO2 treatment resulted in significant reductions in the prostate index and testosterone, DHT, 5α-reductase and COX-2 levels compared with those in BPH-induced animals. Histopathological examination also demonstrated that rape pollen SFE-CO2 treatment suppressed testosterone-induced BPH. These observations indicate that rape pollen SFE-CO2 inhibits the development of BPH in rats and these effects are closely associated with reductions in DHT, 5α-reductase and COX-2 levels. Therefore, the results of the present study clearly indicate that rape pollen SFE-CO2 extract may be a useful agent in BPH treatment. PMID:24944593
Yang, Bi-Cheng; Jin, Li-Li; Yang, Yi-Fang; Li, Kun; Peng, Dan-Ming
2014-07-01
Benign prostatic hyperplasia (BPH) can lead to lower urinary tract symptoms. Rape pollen is an apicultural product that is composed of nutritionally valuable and biologically active substances. The aim of the present study was to investigate the protective effect of rape pollen supercritical CO 2 fluid extract (SFE-CO 2 ) in BPH development using a testosterone-induced BPH rat model. BPH was induced in the experimental groups by daily subcutaneous injections of testosterone for a period of 30 days. Rape pollen SFE-CO 2 was administered daily by oral gavage concurrently with the testosterone injections. Animals were sacrificed at the scheduled termination and the prostates were weighed and subjected to histopathological examination. Testosterone, dihydrotestosterone (DHT), 5α-reductase and cyclooxygenase-2 (COX-2) levels were also measured. BPH-induced animals exhibited an increase in prostate weight with increased testosterone, DHT, 5α-reductase and COX-2 expression levels. However, rape pollen SFE-CO 2 treatment resulted in significant reductions in the prostate index and testosterone, DHT, 5α-reductase and COX-2 levels compared with those in BPH-induced animals. Histopathological examination also demonstrated that rape pollen SFE-CO 2 treatment suppressed testosterone-induced BPH. These observations indicate that rape pollen SFE-CO 2 inhibits the development of BPH in rats and these effects are closely associated with reductions in DHT, 5α-reductase and COX-2 levels. Therefore, the results of the present study clearly indicate that rape pollen SFE-CO 2 extract may be a useful agent in BPH treatment.
Delivering enhanced testosterone replacement therapy through nanochannels.
Ferrati, Silvia; Nicolov, Eugenia; Bansal, Shyam; Zabre, Erika; Geninatti, Thomas; Ziemys, Arturas; Hudson, Lee; Ferrari, Mauro; Goodall, Randal; Khera, Mohit; Palapattu, Ganesh; Grattoni, Alessandro
2015-02-18
Primary or secondary hypogonadism results in a range of signs and symptoms that compromise quality of life and requires life-long testosterone replacement therapy. In this study, an implantable nanochannel system is investigated as an alternative delivery strategy for the long-term sustained and constant release of testosterone. In vitro release tests are performed using a dissolution set up, with testosterone and testosterone:2-hydroxypropyl-β-cyclodextrin (TES:HPCD) 1:1 and 1:2 molar ratio complexes release from the implantable nanochannel system and quantify by HPLC. 1:2 TES:HPCD complex stably achieve 10-15 times higher testosterone solubility with 25-30 times higher in vitro release. Bioactivity of delivered testosterone is verified by LNCaP/LUC cell luminescence. In vivo evaluation of testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels by liquid chromatography mass spectrometry (LC/MS) and multiplex assay is performed in castrated Sprague-Dawley rats over 30 d. Animals are treated with the nanochannel implants or degradable testosterone pellets. The 1:2 TES:HPCD nanochannel implant exhibits sustained and clinically relevant in vivo release kinetics and attains physiologically stable plasma levels of testosterone, LH, and FSH. In conclusion, it is demonstrated that by providing long-term steady release 1:2 TES:HPCD nanochannel implants may represent a major breakthrough for the treatment of male hypogonadism. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Idris, Adi; Ghazali, Nur B; Said, Nadzirah M; Steele, Michael; Koh, David; Tuah, Nik A
2016-04-09
Early smoking is considered an indicator for risky behaviour in adolescents. Although social indicators predicting adolescent smoking are known, biological indicators have not been defined. This study aimed to establish whether salivary testosterone could be used as a "predictive biomarker" for smoking-associated peer pressure. Saliva samples were collected from Bruneian adolescents (aged 13-17 years) by the passive drool method. Salivary testosterone concentration was determined by enzyme-linked immunosorbent assay. Salivary testosterone concentration and smoking-associated peer pressure indicators were compared between adolescent males and females and statistical significance was determined by an independent samples t-test. A significant positive relationship between smoking-associated peer pressure and salivary testosterone levels in adolescents was found. However, this relationship was not significant when males and females were considered separately. Our data suggest that students who have tried cigarette smoking and have friends who are cigarette smokers have higher salivary testosterone levels.
Effects of prolonged physical exercise and fasting upon plasma testosterone level in rats.
Guezennec, C Y; Ferre, P; Serrurier, B; Merino, D; Pesquies, P C
1982-01-01
Prolonged physical exercise and fasting in male rats were studied to determine the effect of these two treatments on plasma testosterone level. Blood and tissue samples were drawn after 1 h, 3 h, 5 h, and 7 h treadmill running, and after 24 h, 48 h, and 72 h of fasting. Both treatments resulted in a significant fall in plasma testosterone, plasma luteinizing hormone (LH), plasma Insulin (IRI) and in liver and muscle glycogen stores. In the course of these two treatments the injection of a supra maximal dose of Human Chorionic Gonadotropin (HCG) produced a rise in plasma testosterone similar to that in control rats. This indicates that the decrease of plasma LH may be responsible for the decrease in plasma testosterone, which is time-related with the decrease in glycogen stores. The possible metabolic role of the decrease in plasma testosterone is discussed.
Akinola, Modupe; Page-Gould, Elizabeth; Mehta, Pranjal H; Liu, Zaijia
2018-03-01
Prior research has found inconsistent effects of diversity on group performance. The present research identifies hormonal factors as a critical moderator of the diversity-performance connection. Integrating the diversity, status, and hormone literatures, we predicted that groups collectively low in testosterone, which orients individuals less toward status competitions and more toward cooperation, would excel with greater group diversity. In contrast, groups collectively high in testosterone, which is associated with a heightened status drive, would be derailed by diversity. Analysis of 74 randomly assigned groups engaged in a group decision-making exercise provided support for these hypotheses. The findings suggest that diversity is beneficial for performance, but only if group-level testosterone is low; diversity has a negative effect on performance if group-level testosterone is high. Too much collective testosterone maximizes the pains and minimizes the gains from diversity.
2013-01-01
Background To explore novel platinum-based anticancer agents that are distinct from the structure and interaction mode of the traditional cisplatin by forming the bifunctional intrastrand 1,2 GpG adduct, the monofunctional platinum + DNA adducts with extensive non-covalent interactions had been studied. It was reported that the monofunctional testosterone-based platinum(II) agents present the high anticancer activity. Moreover, it was also found that the testosterone-based platinum agents could cause the DNA helix to undergo significant unwinding and bending over the non-testosterone-based platinum agents. However, the interaction mechanisms of these platinum agents with DNA at the atomic level are not yet clear so far. Results In the present work, we used molecular dynamics (MD) simulations and DNA conformational dynamics calculations to study the DNA distortion properties of the testosterone-based platinum + DNA, the improved testosterone-based platinum + DNA and the non-testosterone-based platinum + DNA adducts. The results show that the intercalative interaction of the improved flexible testosterone-based platinum agent with DNA molecule could cause larger DNA conformational distortion than the groove-face interaction of the rigid testosterone-based platinum agent with DNA molecule. Further investigations for the non-testosterone-based platinum agent reveal the occurrence of insignificant change of DNA conformation due to the absence of testosterone ligand in such agent. Based on the DNA dynamics analysis, the DNA base motions relating to DNA groove parameter changes and hydrogen bond destruction of DNA base pairs were also discussed in this work. Conclusions The flexible linker in the improved testosterone-based platinum agent causes an intercalative interaction with DNA in the improved testosterone-based platinum + DNA adduct, which is different from the groove-face interaction caused by a rigid linker in the testosterone-based platinum agent. The present investigations provide useful information of DNA conformation affected by a testosterone-based platinum complex at the atomic level. PMID:23517640
Iwasa, Takeshi; Matsuzaki, Toshiya; Yiliyasi, Mayila; Yano, Kiyohito; Irahara, Minoru
2017-11-01
Previously, we showed that chronic testosterone administration increased body weight (BW) and food intake (FI), but did not alter fat weight, in young female rats. To examine our hypothesis that the effects of androgens on BW, FI and body composition might be age-dependent, the effects of chronic testosterone administration were evaluated in rats of different ages; i.e., young and middle-aged rats. Although chronic testosterone administration increased BW gain, FI, and feed efficiency in both young and middle-aged rats, it increased visceral fat weight in middle-aged rats, but not in young rats. Therefore, it is possible that testosterone promotes the conversion of energy to adipose tissue and exacerbates fat accumulation in older individuals. In addition, although the administration of testosterone increased the serum leptin level, it did not alter hypothalamic neuropeptide Y mRNA expression in middle-aged rats. On the contrary, the administration of testosterone did not affect the serum leptin levels of young rats. Thus, testosterone might induce hypothalamic leptin resistance, which could lead to fat accumulation in older individuals. Testosterone might disrupt the mechanisms that protect against adiposity and hyperphagia and represent a risk factor for excessive body weight and obesity, especially in older females. Copyright © 2017 Elsevier Inc. All rights reserved.
Leiber, C; Wetterauer, U; Berner, M
2010-01-01
Testosterone, like other steroid hormones, crosses the blood-brain barrier, and the androgen receptor is present in most parts of the human brain. Therefore, testosterone has many effects on the psyche, mainly in men but also in women. Most often discussed is its influence on sexuality, especially on desire and sexual fantasies, spontaneous nighttime erections, sexual activity, and the number of orgasms and ejaculations. Mood and energy are also testosterone related. Testosterone deficiency in male patients can lead to depressive disorders. In the past, elevated testosterone levels were seen as responsible for strongly aggressive behaviour. Some cognitive functions (spatial and mathematical sense, verbal skills) are, at least to a certain point, testosterone related. Due to the extremely complex functioning of the human brain, a scientifically exact statement regarding the true relationship between testosterone and human behaviour is not possible. On the one hand, the cause is definitively multifactorial, but on the other, testosterone is metabolised in the brain, and the metabolites act by themselves. Furthermore, a bidirectional relationship exists between hormones and human behaviour: Human behaviour is influenced by hormones, and human behaviour also has a direct influence on the levels of many hormones in the human body. Finally, much data in this field are derived from animal studies; studies on humans cannot be conducted because of ethical reasons or scientific and technical problems.
Wistuba, Joachim; Marc Luetjens, C; Kamischke, Axel; Gu, Yi-Qun; Schlatt, Stefan; Simoni, Manuela; Nieschlag, Eberhard
2005-08-01
Testosterone undecanoate (TU) dissolved in soybean oil was developed in China to improve the pharmacokinetics of this testosterone ester in comparison with TU in castor or tea seed oil. As a pre-clinical primate model, three groups of five castrated cynomolgus macaques received either a single intramuscular injection of 10 mg/kg body weight TU in soybean oil, in tea seed oil, or in castor oil (equals 6.3 mg pure T/kg body weight for all preparations). Testosterone, estradiol, luteinizing hormone, and follicle-stimulating hormone as well as prostate volume, body weight and ejaculate weight were evaluated. After injection supraphysiological testosterone levels were induced. There were no significant differences in the pharmacokinetics of the three TU preparations for testosterone and estradiol. The gonadotropin levels showed a high individual variation. Prostate volumes increased equally in all groups after administration and declined to castrate level afterwards. The results suggest that TU in soybean oil produces similar effects as TU in the other vehicles. This study in non-human primates provides no objection to testing of this new preparation in humans.
The association of total antioxidant capacity with sex hormones.
Demirbag, Recep; Yilmaz, Remzi; Erel, Ozcan
2005-07-01
Although sex hormones have potential cardioprotective effects, their effects on total antioxidant capacity (TAC) are not very well known. The aim of the study was to evaluate TAC in men who have decreased and normal testosterone levels and in women in menopausal and premenopausal period. Ninety-seven subjects with similar age intervals, men aged <45 years and female aged <50 years, were divided into four groups: 1) 10 men with normal testosterone levels, as control, 2) 36 men with decreased testosterone, 3) 19 women in menopause, surgically induced, and 4) 32 women in premenopausal period. Testosterone and estrogen levels were measured by chemiluminescence assay and TAC were measured by using a more recently developed automated measurement method. The TAC was significantly lower in Group 2 and Group 3 than those of Group 1 and Group 4 (ANOVA, p<0.001). A strong correlation between TAC, and testosterone and estrogen were found (r=0.807, p<0.001; r=0.685, p<0.001, testosterone and estrogen respectively). The observed relationship between sex hormones and TAC may have a role in mechanism of their cardioprotective effect.
Peskoe, Sarah B; Joshu, Corinne E; Rohrmann, Sabine; McGlynn, Katherine A; Nyante, Sarah J; Bradwin, Gary; Dobs, Adrian S; Kanarek, Norma; Nelson, William G; Platz, Elizabeth A
2015-08-01
The association between serum sex steroid hormones and PSA in a general population has not been described. Included were 378 men aged 40-85 years who participated in the National Health and Nutrition Examination Survey in 2001-2004, who did not have a prostate cancer diagnosis, and had not had a recent biopsy, rectal examination, cystoscopy, or prostate infection or inflammation. Serum total PSA, total testosterone, androstanediol glucuronide (3α-diol-G), estradiol, and sex hormone binding globulin (SHBG) concentrations were previously measured. Free testosterone was estimated by mass action. We applied sampling weights and calculated geometric mean PSA concentration by hormone quintiles adjusting for age and race/ethnicity, and also for body mass index, waist circumference, smoking, diabetes, and mutually for hormones. We estimated the OR of PSA ≥2.5 ng/ml per hormone quintile using logistic regression. Geometric mean PSA increased across testosterone quintiles after age and race/ethnicity (Q1: 0.80, Q5: 1.14 ng/ml; P-trend = 0.002) and multivariable (Q1: 0.79, Q5: 1.16 ng/ml; P-trend = 0.02) adjustment; patterns were similar for free testosterone and 3α-diol-G. SHBG was inversely associated with PSA only after multivariable adjustment (Q1: 1.32, Q5: 0.82 nmol/L; P-trend = 0.01). Estradiol and PSA were not associated. The OR of PSA ≥2.5 ng/ml was 1.54 (95% CI 1.18-2.01) per testosterone quintile after age and race/ethnicity adjustment, and 1.78 (95% CI 1.16-2.73) after multivariable adjustment. In this nationally representative sample, men with higher testosterone had higher PSA even after taking into account other hormones and modifiable factors. Men with higher SHBG had lower PSA, but only after multivariable adjustment. © 2015 Wiley Periodicals, Inc.
Equol an isoflavonoid: potential for improved prostate health, in vitro and in vivo evidence
2011-01-01
Background To determine: in vitro binding affinity of equol for 5alpha-dihydrotestosterone (5alpha-DHT), in vitro effects of equol treatment in human prostate cancer (LNCap) cells, and in vivo effects of equol on rat prostate weight and circulating levels of sex steroid hormones. Methods First, in vitro equol binding affinity for 5alpha-DHT was determined using 14C5alpha-DHT combined with cold 5alpha-DHT (3.0 nM in all samples). These steroids were incubated with increasing concentrations of equol (0-2,000 nM) and analyzed by Sephadex LH-20 column chromatography. 14C5alpha-DHT peak/profiles were determined by scintillation counting of column fractions. Using the 14C5alpha-DHT peak (0 nM equol) as a reference standard, a binding curve was generated by quantifying shifts in the 14C5alpha-DHT peaks as equol concentrations increased. Second, equol's in vitro effects on LNCap cells were determined by culturing cells (48 hours) in the presence of increasing concentrations of dimethyl sulfoxide (DMSO) (vehicle-control), 5alpha-DHT, equol or 5alpha-DHT+equol. Following culture, prostate specific antigen (PSA) levels were quantified via ELISA. Finally, the in vivo effects of equol were tested in sixteen male Long-Evans rats fed a low isoflavone diet. From 190-215 days, animals received 0.1cc s.c. injections of either DMSO-control vehicle (n = 8) or 1.0 mg/kg (body weight) of equol (in DMSO) (n = 8). At 215 days, body and prostate weights were recorded, trunk blood was collected and serum assayed for luteinizing hormone (LH), 5alpha-DHT, testosterone and 17beta-estradiol levels. Results Maximum and half maximal equol binding to 5alpha-DHT occurred at approximately 100 nM and 4.8 nM respectively. LNCap cells cultured in the presence of 5alpha-DHT significantly increased PSA levels. However, in the presence of 5alpha-DHT+equol, equol blocked the significant increases in PSA levels from LNCap cells. In vivo equol treatment significantly decreased rat prostate weights and serum 5alpha-DHT levels but did not alter LH, testosterone, and estradiol levels. Conclusions Equol administration appears to have potential beneficial effects for prostate health and other 5alpha-DHT mediated disorders. Equol administration: reduces PSA levels from LNCap cells under 5alpha-DHT stimulation, decreases rat prostate size, decreases serum 5alpha-DHT levels and androgen hormone action, while not altering other circulating sex steroids or LH levels. PMID:21232127
Krajnak, K; Sriram, K; Johnson, C; Roberts, J R; Mercer, R; Miller, G R; Wirth, O; Antonini, J M
2017-01-01
Exposure to welding fumes may result in disorders of the pulmonary, cardiovascular, and reproductive systems. Welders are also at a greater risk of developing symptoms similar to those seen in individuals with idiopathic Parkinson's disease. In welders, there are studies that suggest that alterations in circulating prolactin concentrations may be indicative of injury to the dopamine (DA) neurons in the substantia nigra. The goal of these studies was to use an established model of welding particulate exposure to mimic the effects of welding fume inhalation on reproductive functions. Since previous investigators suggested that changes in circulating prolactin may be an early marker of DA neuron injury, movement disorders, and reproductive dysfunction, prolactin, hypothalamic tyrosine hydroxylase (TH) levels (a marker of DA synthesis), and other measures of hypothalamic-pituitary-gonadal (HPG) function were measured after repetitive instillation of welding fume particulates generated by flux core arc-hard surfacing (FCA-HS), manual metal arc-hard surfacing (MMA-HS) or gas metal arc-mild steel (GMA-MS) welding, or manganese chloride (MnCl 2 ). Exposure to welding fume particulate resulted in the accumulation of various metals in the pituitary and testes of rats, along with changes in hypothalamic TH and serum prolactin levels. Exposure to particulates with high concentrations of soluble manganese (Mn) appeared to exert the greatest influence on TH activity levels and serum prolactin concentrations. Thus, circulating prolactin levels may serve as a biomarker for welding fume/Mn-induced neurotoxicity. Other reproductive measures were collected, and these data were consistent with epidemiological findings that prolactin and testosterone may serve as biomarkers of welding particulate induced DA neuron and reproductive dysfunction.
Cho, June; Su, Xiaogang; Phillips, Vivien; Holditch-Davis, Diane
2015-01-01
This study examined the associations of testosterone and cortisol levels with maternal depressive symptoms and infant socioemotional (SE) problems that are influenced by infant gender. A total of 62 mothers and their very-low-birth weight (VLBW) infants were recruited from a neonatal intensive care unit at a tertiary medical center in the southeast United States. Data were collected at three time points (before 40 weeks’ postmenstrual age [PMA] and at 3 months and 6 months of age corrected for prematurity). Measures included infant medical record review, maternal interview, biochemical assays of salivary hormone levels in mother-VLBWinfant pairs, and standard questionnaires. Generalized estimating equations with separate analyses for boys and girls showed that maternal testosterone level was negatively associated with depressive symptoms in mothers of boys, whereas infant testosterone level was negatively associated with maternal report of infant SE problems in girls after controlling for characteristics of mothers and infants and number of days post birth of saliva collection. Not surprisingly, the SE problems were positively associated with a number of medical complications. Mothers with more depressive symptoms reported that their infants had more SE problems. Mothers with higher testosterone levels reported that girls, but not boys, had fewer SE problems. In summary, high levels of testosterone could have a protective role for maternal depressive symptoms and infant SE problems. Future research need to be directed toward clinical application of these preliminary results. PMID:25954021
Cho, June; Su, Xiaogang; Phillips, Vivien; Holditch-Davis, Diane
2016-01-01
This study examined the associations of testosterone and cortisol levels with maternal depressive symptoms and infant socioemotional (SE) problems that are influenced by infant gender. A total of 62 mothers and their very-low-birth weight (VLBW) infants were recruited from a neonatal intensive care unit at a tertiary medical center in the southeast United States. Data were collected at three time points (before 40 weeks' postmenstrual age [PMA] and at 3 months and 6 months of age corrected for prematurity). Measures included infant medical record review, maternal interview, biochemical assays of salivary hormone levels in mother-VLBWinfant pairs, and standard questionnaires. Generalized estimating equations with separate analyses for boys and girls showed that maternal testosterone level was negatively associated with depressive symptoms in mothers of boys, whereas infant testosterone level was negatively associated with maternal report of infant SE problems in girls after controlling for characteristics of mothers and infants and number of days post birth of saliva collection. Not surprisingly, the SE problems were positively associated with a number of medical complications. Mothers with more depressive symptoms reported that their infants had more SE problems. Mothers with higher testosterone levels reported that girls, but not boys, had fewer SE problems. In summary, high levels of testosterone could have a protective role for maternal depressive symptoms and infant SE problems. Future research need to be directed toward clinical application of these preliminary results. © The Author(s) 2015.
Cortisol and testosterone increase financial risk taking and may destabilize markets.
Cueva, Carlos; Roberts, R Edward; Spencer, Tom; Rani, Nisha; Tempest, Michelle; Tobler, Philippe N; Herbert, Joe; Rustichini, Aldo
2015-07-02
It is widely known that financial markets can become dangerously unstable, yet it is unclear why. Recent research has highlighted the possibility that endogenous hormones, in particular testosterone and cortisol, may critically influence traders' financial decision making. Here we show that cortisol, a hormone that modulates the response to physical or psychological stress, predicts instability in financial markets. Specifically, we recorded salivary levels of cortisol and testosterone in people participating in an experimental asset market (N = 142) and found that individual and aggregate levels of endogenous cortisol predict subsequent risk-taking and price instability. We then administered either cortisol (single oral dose of 100 mg hydrocortisone, N = 34) or testosterone (three doses of 10 g transdermal 1% testosterone gel over 48 hours, N = 41) to young males before they played an asset trading game. We found that both cortisol and testosterone shifted investment towards riskier assets. Cortisol appears to affect risk preferences directly, whereas testosterone operates by inducing increased optimism about future price changes. Our results suggest that changes in both cortisol and testosterone could play a destabilizing role in financial markets through increased risk taking behaviour, acting via different behavioural pathways.
Cortisol and testosterone increase financial risk taking and may destabilize markets
Cueva, Carlos; Roberts, R. Edward; Spencer, Tom; Rani, Nisha; Tempest, Michelle; Tobler, Philippe N.; Herbert, Joe; Rustichini, Aldo
2015-01-01
It is widely known that financial markets can become dangerously unstable, yet it is unclear why. Recent research has highlighted the possibility that endogenous hormones, in particular testosterone and cortisol, may critically influence traders’ financial decision making. Here we show that cortisol, a hormone that modulates the response to physical or psychological stress, predicts instability in financial markets. Specifically, we recorded salivary levels of cortisol and testosterone in people participating in an experimental asset market (N = 142) and found that individual and aggregate levels of endogenous cortisol predict subsequent risk-taking and price instability. We then administered either cortisol (single oral dose of 100 mg hydrocortisone, N = 34) or testosterone (three doses of 10 g transdermal 1% testosterone gel over 48 hours, N = 41) to young males before they played an asset trading game. We found that both cortisol and testosterone shifted investment towards riskier assets. Cortisol appears to affect risk preferences directly, whereas testosterone operates by inducing increased optimism about future price changes. Our results suggest that changes in both cortisol and testosterone could play a destabilizing role in financial markets through increased risk taking behaviour, acting via different behavioural pathways. PMID:26135946
Dominance and testosterone in women.
Grant, V J; France, J T
2001-09-01
Fifty-two young women completed the Simple Adjective Test (a questionnaire designed to measure dominance) and at the same time provided 5 ml blood for testosterone assay. Higher dominance scores were associated with higher serum testosterone levels (t-test P<0.008).
Relationships between Circulating and Intraprostatic Sex Steroid Hormone Concentrations.
Cook, Michael B; Stanczyk, Frank Z; Wood, Shannon N; Pfeiffer, Ruth M; Hafi, Muhannad; Veneroso, Carmela C; Lynch, Barlow; Falk, Roni T; Zhou, Cindy Ke; Niwa, Shelley; Emanuel, Eric; Gao, Yu-Tang; Hemstreet, George P; Zolfghari, Ladan; Carroll, Peter R; Manyak, Michael J; Sesterhann, Isabell A; Levine, Paul H; Hsing, Ann W
2017-11-01
Background: Sex hormones have been implicated in prostate carcinogenesis, yet epidemiologic studies have not provided substantiating evidence. We tested the hypothesis that circulating concentrations of sex steroid hormones reflect intraprostatic concentrations using serum and adjacent microscopically verified benign prostate tissue from prostate cancer cases. Methods: Incident localized prostate cancer cases scheduled for surgery were invited to participate. Consented participants completed surveys, and provided resected tissues and blood. Histologic assessment of the ends of fresh frozen tissue confirmed adjacent microscopically verified benign pathology. Sex steroid hormones in sera and tissues were extracted, chromatographically separated, and then quantitated by radioimmunoassays. Linear regression was used to account for variations in intraprostatic hormone concentrations by age, body mass index, race, and study site, and subsequently to assess relationships with serum hormone concentrations. Gleason score (from adjacent tumor tissue), race, and age were assessed as potential effect modifiers. Results: Circulating sex steroid hormone concentrations had low-to-moderate correlations with, and explained small proportions of variations in, intraprostatic sex steroid hormone concentrations. Androstane-3α,17β-diol glucuronide (3α-diol G) explained the highest variance of tissue concentrations of 3α-diol G (linear regression r 2 = 0.21), followed by serum testosterone and tissue dihydrotestosterone ( r 2 = 0.10), and then serum estrone and tissue estrone ( r 2 = 0.09). There was no effect modification by Gleason score, race, or age. Conclusions: Circulating concentrations of sex steroid hormones are poor surrogate measures of the intraprostatic hormonal milieu. Impact: The high exposure misclassification provided by circulating sex steroid hormone concentrations for intraprostatic levels may partly explain the lack of any consistent association of circulating hormones with prostate cancer risk. Cancer Epidemiol Biomarkers Prev; 26(11); 1660-6. ©2017 AACR . ©2017 American Association for Cancer Research.
Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers.
Pandit, S; Biswas, S; Jana, U; De, R K; Mukhopadhyay, S C; Biswas, T K
2016-06-01
Purified Shilajit, an Ayurvedic rasayana, was evaluated in healthy volunteers of age between 45 and 55 years for its effect on male androgenic hormone viz. testosterone in a randomised, double-blind, placebo-controlled clinical study at a dose of 250 mg twice a day. Treatment with Shilajit for consecutive 90 days revealed that it has significantly (P < 0.05) increased total testosterone, free testosterone and dehydroepiandrosterone (DHEAS) compared with placebo. Gonadotropic hormones (LH and FSH) levels were well maintained. © 2015 The Authors. Andrologia Published by Blackwell Verlag GmbH.
Fregeneda-Grandes, Juan M; Hernández-Navarro, Salvador; Fernandez-Coppel, Ignacio A; Correa-Guimaraes, Adriana; Ruíz-Potosme, Norlan; Navas-Gracia, Luis M; Aller-Gancedo, J Miguel; Martín-Gil, Francisco J; Martín-Gil, Jesús
2013-12-01
Serum steroid profiles were investigated in order to evaluate the potential use of circulating sex steroid levels as a tool for sex identification in brown trout. Changes in the serum concentrations of testosterone (T), progesterone (P), 17-β-estradiol (E2), and cortisol (F) in wild and farmed mature female and male brown trout, Salmo trutta L., were measured in each season (January, May, July, and October) in six rivers and four hatcheries located in the north-west of Spain. Serum cortisol levels in farmed brown trout were significantly higher and showed a seasonal pattern opposite to that found in wild trout. Because levels of the hormones under study can be affected by disruptive factors such as exposure to phytoestrogens (which alters the hypothalamic-pituitary-gonadal axis) and infection with Saprolegnia parasitica (which alters the hypothalamic-pituitary-adrenal axis), both factors are taken into account.
Rantala, Markus J; Coetzee, Vinet; Moore, Fhionna R; Skrinda, Ilona; Kecko, Sanita; Krama, Tatjana; Kivleniece, Inese; Krams, Indrikis
2013-08-23
Recent studies suggest that facial attractiveness indicates immune responsiveness in men and that this relationship is moderated by stress hormones which interact with testosterone levels. However, studies testing whether facial attractiveness in women signals their immune responsiveness are lacking. Here, we photographed young Latvian women, vaccinated them against hepatitis B and measured the amount of specific antibodies produced, cortisol levels and percentage body fat. Latvian men rated the attractiveness of the women's faces. Interestingly, in women, immune responsiveness (amount of antibodies produced) did not predict facial attractiveness. Instead, plasma cortisol level was negatively associated with attractiveness, indicating that stressed women look less attractive. Fat percentage was curvilinearly associated with facial attractiveness, indicating that being too thin or too fat reduces attractiveness. Our study suggests that in contrast to men, facial attractiveness in women does not indicate immune responsiveness against hepatitis B, but is associated with two other aspects of long-term health and fertility: circulating levels of the stress hormone cortisol and percentage body fat.
Hormonal studies and physical maturation in adolescent gynecomastia.
Biro, F M; Lucky, A W; Huster, G A; Morrison, J A
1990-03-01
As part of a 3-year longitudinal study of lipid and hormonal changes during puberty, 536 boys aged 10 to 15 years were prospectively followed every 6 months to assess development of gynecomastia. The overall prevalence of gynecomastia in the 377 with complete data was 48.5% (51% of white subjects and 46% of black subjects). In the majority of subjects, gynecomastia developed during mid-puberty. Gynecomastia was bilateral in 55% of subjects, on the left side in 19%, and on the right in 26%. Gynecomastia was documented for only one visit in the majority of subjects. When subjects were matched at the onset of gynecomastia for race, visit number, and pubertal rating, there were no significant differences between those with or without gynecomastia in serum estradiol level, testosterone level, estrogen/testosterone, ratio, or dehydroepiandrosterone-sulfate level. However, free testosterone level, weight, and Quetelet index were all significantly lower, and the testosterone-estrogen binding globulin level was significantly greater, in those with gynecomastia. We conclude that approximately half of adolescent boys have transient gynecomastia, usually lasting less than 1 year; those with gynecomastia enter mid-puberty at an earlier age, have a lower Quetelet index, and have lower serum free testosterone levels.
Dosani, M; Morris, W J; Tyldesley, S; Pickles, T
2017-10-01
This study describes the proportion of men who experienced hot flashes (flashes), and the testosterone level at onset, peak frequency and cessation of flashes after 12 months of androgen deprivation therapy (ADT) in men undergoing curative-intent external beam radiation therapy (± brachytherapy boost). We also aimed to characterise testosterone recovery in this population. This was a pre-specified secondary analysis of the ASCENDE-RT clinical trial. Three hundred and ninety-eight men were randomised. All received 12 months of ADT. The presence and frequency of flashes were patient reported. Cessation of flashes was defined as the first date a patient reported resolution of this symptom. Testosterone recovery was defined as any single serum testosterone above the threshold of 5, 7.5 or 10 nmol/l. The median age and follow-up were 68 years and 6.1 years. Flashes were reported in 93% of men. Flashes began and reached peak frequency at a median time of 4.0 months from the first luteinizing hormone-releasing hormone injection when testosterone levels had fallen to castrate. The median time to cessation of flashes was 7.6 months after the cessation of ADT (last injection + 3 months), when the median testosterone had risen to 5.7 nmol/l. A resolution of flashes was reported in 99% of patients. Baseline testosterone was available in 338 patients (85%). The median baseline testosterone was 13.2 nmol/l. The median (95% confidence interval) time of testosterone recovery to thresholds of 5 nmol/l, 7.5 nmol/l and 10 nmol/l were 9 (9-10) months, 13 (10-15) months and 18 (17-19) months from the cessation of ADT. At the time of censor, 96, 94 and 91% of patients had recovered testosterone to thresholds of 5, 7.5 and 10 nmol/l. Flashes occur at castrate levels of testosterone, with cessation of hot flashes antedating full recovery of testosterone in most patients. Rates of testosterone recovery after 12 months of ADT exceed 90%, although it can be delayed. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Testosterone deficiency: a determinant of aortic stiffness in men.
Vlachopoulos, Charalambos; Ioakeimidis, Nikolaos; Miner, Martin; Aggelis, Athanassios; Pietri, Panagiota; Terentes-Printzios, Dimitrios; Tsekoura, Dorothea; Stefanadis, Christodoulos
2014-03-01
Low testosterone levels and increased aortic stiffness are predictors of cardiovascular events. The influence of androgen level on the age- and blood pressure-related increase in aortic stiffness is unknown. From January 2007 to June 2011 we enrolled 455 consecutive men with no evidence of cardiovascular disease from a large cohort followed in our Department for arterial function studies. Their total testosterone (TT) levels were measured and carotid-femoral pulse wave velocity (PWVc-f) was measured as an index of aortic stiffness. In multivariable analysis, PWVc-f values were inversely correlated to TT after adjustment for confounders (β = -0.365, P < 0.001). In younger age categories (<50 yrs and 50-59 yrs), patients with testosterone deficiency (TD) had higher blood pressure-adjusted PWVc-f (P < 0.001 and P = 0.005, respectively) compared to subjects with normal TT, indicating an "aging effect" of 10 years, whereas in older age categories such a difference was not observed. Furthermore, in men with a higher mean pressure (102-108 mmHg and >108 mmHg), patients with TD had higher age-adjusted PWVc-f (P < 0.001) compared to subjects with normal TT, indicating a synergistic unfavorable effect of testosterone deficiency and blood pressure on aortic stiffness. TT levels are independently associated with aortic stiffening. The effect of low testosterone concentration on aortic stiffness is more prominent in young men and in subjects with higher blood pressure levels. These findings identify testosterone as a marker of arterial damage with special emphasis on young and hypertensive individuals and support its role as predictor of events. Copyright © 2014. Published by Elsevier Ireland Ltd.
Nandrolone Normalizes Determinants of Muscle Mass and Fiber Type after Spinal Cord Injury
Wu, Yong; Zhao, Jingbo; Zhao, Weidong; Pan, Jiangping; Bauman, William A.
2012-01-01
Abstract Spinal cord injury (SCI) results in atrophy of skeletal muscle and changes from slow oxidative to fast glycolytic fibers, which may reflect reduced levels of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), increased myostatin signaling, or both. In animals, testosterone reduces loss of muscle fiber cross-sectional area and activity of enzymes of energy metabolism. To identify the molecular mechanisms behind the benefits of androgens on paralyzed muscle, male rats were spinal cord transected and treated for 8 weeks with vehicle, testosterone at a physiological replacement dose, or testosterone plus nandrolone, an anabolic steroid. Treatments were initiated immediately after SCI and continued until the day animals were euthanized. In the SCI animals, gastrocnemius muscle mass was significantly increased by testosterone plus nandrolone, but not by testosterone alone. Both treatments significantly reduced nuclear content of Smad2/3 and mRNA levels of activin receptor IIB and follistatin-like 3. Testosterone alone or with nandrolone reversed SCI-induced declines in cellular and nuclear levels of PGC-1α protein and PGC-1α mRNA levels. For PGC-1α target genes, testosterone plus nandrolone partially reversed SCI-induced decreases in levels of proteins without corresponding increases in their mRNA levels. Thus, the findings demonstrate that following SCI, signaling through activin receptors and Smad2/3 is increased, and that androgens suppress activation of this signaling pathway. The findings also indicate that androgens upregulate PGC-1α in paralyzed muscle and promote its nuclear localization, but that these effects are insufficient to fully activate transcription of PGC-1α target genes. Furthermore, the transcription of these genes is not tightly coupled with their translation. PMID:22208735
Associations of lead and cadmium with sex hormones in adult males
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kresovich, Jacob K., E-mail: jkreso2@uic.edu; Argos, Maria; Turyk, Mary E.
Heavy metal exposures are ubiquitous in the environment and their relation to sex hormones is not well understood. This paper investigates the associations between selected heavy metals (lead and cadmium) and sex hormones (testosterone, free testosterone, estradiol, free estradiol) as well as other major molecules in the steroid biosynthesis pathway (androstanedione glucuronide and sex-hormone binding globulin (SHBG)). Blood lead and cadmium were selected as biomarkers of exposure, and tested for associations in males using National Health and Nutritional Examination Survey (NHANES) data from 1999–2004. After adjustment for age, race, body mass index, smoking status, diabetes and alcohol intake, blood leadmore » was positively associated with testosterone and SHBG while blood cadmium was positively associated with SHBG. After controlling for additional heavy metal exposure, the associations between lead and testosterone as well as cadmium and SHBG remained significant. Furthermore, the association between blood lead and testosterone was modified by smoking status (P for interaction=0.011), diabetes (P for interaction=0.021) and blood cadmium (P for interaction=0.029). The association between blood cadmium and SHBG levels was modified by blood lead (P for interaction=0.004). This study is the most comprehensive investigation to date regarding the association between heavy metals and sex hormones in males. - Highlights: • We used a nationally representative dataset (NHANES) and employed sample weighting. • We examined associations between lead and cadmium with sex-hormone levels. • Blood lead level was positively associated with serum testosterone and SHBG levels. • Blood cadmium level was positively associated with SHBG levels, modified by lead. • Diabetes, smoking and cadmium modified lead and testosterone association.« less
Nandrolone normalizes determinants of muscle mass and fiber type after spinal cord injury.
Wu, Yong; Zhao, Jingbo; Zhao, Weidong; Pan, Jiangping; Bauman, William A; Cardozo, Christopher P
2012-05-20
Spinal cord injury (SCI) results in atrophy of skeletal muscle and changes from slow oxidative to fast glycolytic fibers, which may reflect reduced levels of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), increased myostatin signaling, or both. In animals, testosterone reduces loss of muscle fiber cross-sectional area and activity of enzymes of energy metabolism. To identify the molecular mechanisms behind the benefits of androgens on paralyzed muscle, male rats were spinal cord transected and treated for 8 weeks with vehicle, testosterone at a physiological replacement dose, or testosterone plus nandrolone, an anabolic steroid. Treatments were initiated immediately after SCI and continued until the day animals were euthanized. In the SCI animals, gastrocnemius muscle mass was significantly increased by testosterone plus nandrolone, but not by testosterone alone. Both treatments significantly reduced nuclear content of Smad2/3 and mRNA levels of activin receptor IIB and follistatin-like 3. Testosterone alone or with nandrolone reversed SCI-induced declines in cellular and nuclear levels of PGC-1α protein and PGC-1α mRNA levels. For PGC-1α target genes, testosterone plus nandrolone partially reversed SCI-induced decreases in levels of proteins without corresponding increases in their mRNA levels. Thus, the findings demonstrate that following SCI, signaling through activin receptors and Smad2/3 is increased, and that androgens suppress activation of this signaling pathway. The findings also indicate that androgens upregulate PGC-1α in paralyzed muscle and promote its nuclear localization, but that these effects are insufficient to fully activate transcription of PGC-1α target genes. Furthermore, the transcription of these genes is not tightly coupled with their translation.
Associations of sex steroid hormones with mortality in women with breast cancer.
Duggan, Catherine; Stanczyk, Frank; Campbell, Kristin; Neuhouser, Marian L; Baumgartner, Richard N; Baumgartner, Kathy B; Bernstein, Leslie; Ballard, Rachel; McTiernan, Anne
2016-02-01
Epidemiological studies have demonstrated associations between circulating levels of sex steroid hormones and risk of breast cancer in postmenopausal women. However, data on associations with breast cancer survival are limited. We measured levels of estradiol, estrone, testosterone, and sex hormone-binding globulin (SHBG), in serum collected on average 30 months after diagnosis from 358 postmenopausal women diagnosed with stage I-IIIA breast cancer between 1995 and 1998 who participated in a multiethnic, prospective cohort study. Women were followed through December, 2012. We evaluated associations between log-transformed analytes and breast cancer-specific and all-cause mortality fitting multivariable Cox proportional hazards models. Over a median of 14.5 years of follow-up, 102 deaths occurred; 43 of these were due to breast cancer. In models adjusted for ethnicity/study site, age, body mass index, and tumor stage, increased levels of log-transformed SHBG were associated with reduced risk of both breast cancer-specific mortality (hazard ratio, HR 0.48; 95 % confidence interval, CI 0.26-0.89) and all-cause mortality (HR 0.64, 95 % CI 0.43-0.97). There were no associations between levels of estradiol, estrone, or testosterone for either endpoint. In subgroup analyses, after correction for multiple testing, increased estrone was significantly associated with reduced risk for breast cancer-specific mortality among participants with ER-negative tumors (HR 0.16, 95 % CI 0.05-0.63) but not among participants with ER-positive tumors. Increased serum levels of SHBG were associated with decreased risk of breast cancer-specific and all-cause mortality in women with breast cancer. These results should be confirmed in larger breast cancer survivor cohorts.
Nguyen, Tuong-Vi; Lew, Jimin; Albaugh, Matthew D; Botteron, Kelly N; Hudziak, James J; Fonov, Vladimir S; Collins, D Louis; Ducharme, Simon; McCracken, James T
2017-02-01
Testosterone is thought to play a crucial role in mediating sexual differentiation of brain structures. Examinations of the cognitive effects of testosterone have also shown beneficial and potentially sex-specific effects on executive function and mnemonic processes. Yet these findings remain limited by an incomplete understanding of the critical timing and brain regions most affected by testosterone, the lack of documented links between testosterone-related structural brain changes and cognition, and the difficulty in distinguishing the effects of testosterone from those of related sex steroids such as of estradiol and dehydroepiandrosterone (DHEA). Here we examined associations between testosterone, cortico-hippocampal structural covariance, executive function (Behavior Rating Inventory of Executive Function) and verbal memory (California Verbal Learning Test-Children's Version), in a longitudinal sample of typically developing children and adolescents 6-22 yo, controlling for the effects of estradiol, DHEA, pubertal stage, collection time, age, handedness, and total brain volume. We found prefrontal-hippocampal covariance to vary as a function of testosterone levels, but only in boys. Boys also showed a specific association between positive prefrontal-hippocampal covariance (as seen at higher testosterone levels) and lower performance on specific components of executive function (monitoring the action process and flexibly shifting between actions). We also found the association between testosterone and a specific aspect of executive function (monitoring) to be significantly mediated by prefrontal-hippocampal structural covariance. There were no significant associations between testosterone-related cortico-hippocampal covariance and verbal memory. Taken together, these findings highlight the developmental importance of testosterone in supporting sexual differentiation of the brain and sex-specific executive function. Copyright © 2016 Elsevier Ltd. All rights reserved.
Zou, Zhiran; Wang, Dan; Lu, Yapeng; Dong, Zhangji; Zhu, Li
2017-01-01
Male fertility disorders play a key role in half of all infertility cases. Reduction in testosterone induced by hypoxia might cause diseases in reproductive system and other organs. Hypoxic exposure caused a significant decrease of NRF1. Software analysis reported that the promoter region of steroidogenic acute regulatory protein (StAR) contained NRF1 binding sites, indicating NRF1 promoted testicular steroidogenesis. The purpose of this study is to determine NRF1 is involved in testosterone synthesis; and under hypoxia, the decrease of testosterone synthesis is caused by lower expression of NRF1. We designed both in vivo and in vitro experiments. Under hypoxia, the expressions of NRF1 in Leydig cells and testosterone level were significantly decreased both in vivo and in vitro. Overexpression and interference NRF1 could induced StAR and testosterone increased and decreased respectively. ChIP results confirmed the binding of NRF1 to StAR promoter region. In conclusion, decline of NRF1 expression downregulated the level of StAR, which ultimately resulted in a reduction in testosterone synthesis. PMID:28146428
Surampudi, Prasanth N.; Wang, Christina; Swerdloff, Ronald
2012-01-01
Hypogonadism in older men is a syndrome characterized by low serum testosterone levels and clinical symptoms often seen in hypogonadal men of younger age. These symptoms include decreased libido, erectile dysfunction, decreased vitality, decreased muscle mass, increased adiposity, depressed mood, osteopenia, and osteoporosis. Hypogonadism is a common disorder in aging men with a significant percentage of men over 60 years of age having serum testosterone levels below the lower limits of young male adults. There are a variety of testosterone formulations available for treatment of hypogonadism. Data from many small studies indicate that testosterone therapy offers several potential benefits to older hypogonadal men. A large multicenter NIH supported double blind, placebo controlled study is ongoing, and this study should greatly enhance the information available on efficacy and side effects of treatment. While safety data is available across many age groups, there are still unresolved concerns associated with testosterone therapy. We have reviewed the diagnostic methods as well as benefits and risks of testosterone replacement therapy for hypogonadism in aging men. PMID:22505891
Devkota, Bhuminand; Takahashi, Ken-Ichi; Matsuzaki, Shigenori; Matsui, Motozumi; Miyamoto, Akio; Yamagishi, Norio; Osawa, Takeshi; Hashizume, Tsutomu; Izaike, Yoshiaki; Miyake, Yoh-Ichi
2011-06-01
The present study investigated the basal levels and GnRH-induced responses of peripheral testosterone and estrogen in Holstein bulls with poor semen quality. On the basis of semen parameters, bulls (n=5) having poor semen quality were selected as experimental bulls, and good semen quality bulls (n=4) were used as control bulls. Both groups were treated intramuscularly once with GnRH (250 µg of fertirelin acetate). Blood samples were collected at -1 day (d), -30 min and 0 h (treatment) followed by every 30 min for 5 h and 1, 3 and 5 d post-GnRH treatment (PGT), and LH, testosterone and estradiol-17β (E(2)) concentrations were measured. The pretreatment concentrations were used as basal levels. The percentage increments based on the 0-h levels were calculated per bull for each sampling time until 5 h PGT, and differences were compared between the experimental and control groups. The PGT concentrations of testosterone and basal and PGT concentrations of E(2) were significantly lower in the experimental group. The testosterone increment in the experimental group was delayed and significantly lower from 1 to 5 h PGT than those in the control group. It can be suggested that bulls with poor semen quality have delayed and lower GnRH-induced testosterone response and may also have lower estrogen levels.
Farnia, Vahid; Tatari, Faeze; Alikhani, Mostafa; Shakeri, Jalal; Taghizadeh, Moshen; Karbasizadeh, Hassan; Sadeghi Bahmani, Dena; Holsboer-Trachsler, Edith; Brand, Serge
2017-07-01
Some patients with opioid use disorder (OUD) are treated with methadone maintenance therapy (MMT). However, as with opioids, methadone has major side-effects; sexual dysfunction is a particularly distressing such effect. Rosa Damascena oil has been shown to reduce subjective sexual dysfunction in patients with major depressive disorders, but its influence on testosterone has not so far been tested. The aim of the present study was to investigate the influence of Rosa Damascena oil on sexual dysfunction and testosterone levels among male patients with OUD and undergoing MMT. A total of 50 male patients (mean age: 40 years) diagnosed with OUD and receiving MMT were randomly assigned either to the Rosa Damascena oil (drops) or a placebo condition. At baseline, and four and eight weeks later, patients completed questionnaires covering sexual and erectile function. Blood samples to assess testosterone levels were taken at baseline and eight weeks later on completion of the study. Over time sexual dysfunction decreased, and testosterone increased in the Rosa Damascena oil, but not in the placebo condition. Sexual dysfunction scores and testosterone levels were not consistently related. Results from this double-blind, randomized, and placebo-controlled clinical trial showed that Rosa Damascena oil improved sexual function and testosterone levels among males with OUD and undergoing MMT. Copyright © 2017 Elsevier B.V. All rights reserved.
Testosterone and cortisol release among Spanish soccer fans watching the 2010 World Cup final.
van der Meij, Leander; Almela, Mercedes; Hidalgo, Vanesa; Villada, Carolina; Ijzerman, Hans; van Lange, Paul A M; Salvador, Alicia
2012-01-01
This field study investigated the release of testosterone and cortisol of a vicarious winning experience in Spanish fans watching the finals between Spain and the Netherlands in the 2010 FIFA World Cup Soccer. Spanish fans (n = 50) watched the match with friends or family in a public place or at home and also participated in a control condition. Consistent with hypotheses, results revealed that testosterone and cortisol levels were higher when watching the match than on a control day. However, neither testosterone nor cortisol levels increased after the victory of the Spanish team. Moreover, the increase in testosterone secretion was not related to participants' sex, age or soccer fandom, but the increase in total cortisol secretion during the match was higher among men than among women and among fans that were younger. Also, increases in cortisol secretion were greater to the degree that people were a stronger fan of soccer. Level of fandom further appeared to account for the sex effect, but not for the age effect. Generally, the testosterone data from this study are in line with the challenge hypothesis, as testosterone levels of watchers increased to prepare their organism to defend or enhance their social status. The cortisol data from this study are in line with social self-preservation theory, as higher cortisol secretion among young and greater soccer fans suggests that especially they perceived that a negative outcome of the match would threaten their own social esteem.
Testosterone and Cortisol Release among Spanish Soccer Fans Watching the 2010 World Cup Final
van der Meij, Leander; Almela, Mercedes; Hidalgo, Vanesa; Villada, Carolina; IJzerman, Hans; van Lange, Paul A. M.; Salvador, Alicia
2012-01-01
This field study investigated the release of testosterone and cortisol of a vicarious winning experience in Spanish fans watching the finals between Spain and the Netherlands in the 2010 FIFA World Cup Soccer. Spanish fans (n = 50) watched the match with friends or family in a public place or at home and also participated in a control condition. Consistent with hypotheses, results revealed that testosterone and cortisol levels were higher when watching the match than on a control day. However, neither testosterone nor cortisol levels increased after the victory of the Spanish team. Moreover, the increase in testosterone secretion was not related to participants' sex, age or soccer fandom, but the increase in total cortisol secretion during the match was higher among men than among women and among fans that were younger. Also, increases in cortisol secretion were greater to the degree that people were a stronger fan of soccer. Level of fandom further appeared to account for the sex effect, but not for the age effect. Generally, the testosterone data from this study are in line with the challenge hypothesis, as testosterone levels of watchers increased to prepare their organism to defend or enhance their social status. The cortisol data from this study are in line with social self-preservation theory, as higher cortisol secretion among young and greater soccer fans suggests that especially they perceived that a negative outcome of the match would threaten their own social esteem. PMID:22529940
Cristina, Romeo Teodor; Hanganu, Flavia; Dumitrescu, Eugenia; Muselin, Florin; Butnariu, Monica; Constantin, Adriana; Chiurciu, Viorica
2014-01-01
The impact of exogenic testosterone (T): 1.5 and 3.0 mg/kg.bw) and 19-nortestosterone 17-decanoate (ND): 1.5 and 7.5 mg/kg.bw) in castrated male rats was evaluated based on: (a) weight increase of the androgen target tissues, respecting the Hershberger methodology; (b) the 17α and β-testosterone, 17 α and β-estradiol and 17 α and β-nortestosterone levels using the GC-MS/MS technique; and (c) observation of the serum free thyroxine levels (T4). Results revealed that T and ND significantly increased the weight of androgen target tissues as follows: ND was more influential on seminal vesicles, levator ani-bulbocavernosus muscle (LABC) and Cowper's glands and T (at a dose of 3.0 mg/kg.bw) influenced the weight of the ventral prostate and glans penis. Serum samples analyzed for steroid hormone levels showed the presence of 17β-testosterone, 17β-estradiol and 17β-nor-testosterone, in castrated male rats injected with testosterone and nortestosterone, but no significant differences were found between thyroid responses and thyroid hormone levels. The results of this research proved the disrupting activity of T and ND when administered in high doses and the useful application of the Hershberger bioassay in the case of ND. PMID:25302584
Shangguan, Fangfang; Liu, Tongran; Liu, Xiuying; Shi, Jiannong
2017-01-01
Cognitive control is related to goal-directed self-regulation abilities, which is fundamental for human development. Conflict control includes the neural processes of conflict monitoring and conflict resolution. Testosterone and cortisol are essential hormones for the development of cognitive functions. However, there are no studies that have investigated the correlation of these two hormones with conflict control in preadolescents. In this study, we aimed to explore whether testosterone, cortisol, and testosterone/cortisol ratio worked differently for preadolescent's conflict control processes in varied conflict control tasks. Thirty-two 10-year-old children (16 boys and 16 girls) were enrolled. They were instructed to accomplish three conflict control tasks with different conflict dimensions, including the Flanker, Simon, and Stroop tasks, and electrophysiological signals were recorded. Salivary samples were collected from each child. The testosterone and cortisol levels were determined by enzyme-linked immunosorbent assay. The electrophysiological results showed that the incongruent trials induced greater N2/N450 and P3/SP responses than the congruent trials during neural processes of conflict monitoring and conflict resolution in the Flanker and Stroop tasks. The hormonal findings showed that (1) the testosterone/cortisol ratio was correlated with conflict control accuracy and conflict resolution in the Flanker task; (2) the testosterone level was associated with conflict control performance and neural processing of conflict resolution in the Stroop task; (3) the cortisol level was correlated with conflict control performance and neural processing of conflict monitoring in the Simon task. In conclusion, in 10-year-old children, the fewer processes a task needs, the more likely there is an association between the T/C ratios and the behavioral and brain response, and the dual-hormone effects on conflict resolution may be testosterone-driven in the Stroop and Flanker tasks.
Testosterone Regulates NUCB2 mRNA Expression in Male Mouse Hypothalamus and Pituitary Gland
Seon, Sojeong; Jeon, Daun; Kim, Heejeong; Chung, Yiwa; Choi, Narae; Yang, Hyunwon
2017-01-01
ABSTRACT Nesfatin-1/NUCB2 is known to take part in the control of the appetite and energy metabolism. Recently, many reports have shown nesfatin-1/NUCB2 expression and function in various organs. We previously demonstrated that nesfatin-1/NUCB2 expression level is higher in the pituitary gland compared to other organs and its expression is regulated by 17β-estradiol and progesterone secreted from the ovary. However, currently no data exist on the expression of nesfatin-1/NUCB2 and its regulation mechanism in the pituitary of male mouse. Therefore, we examined whether nesfatin-1/NUCB2 is expressed in the male mouse pituitary and if its expression is regulated by testosterone. As a result of PCR and western blotting, we found that a large amount of nesfatin-1/NUCB2 was expressed in the pituitary and hypothalamus. The NUCB2 mRNA expression level in the pituitary was decreased after castration, but not in the hypothalamus. In addition, its mRNA expression level in the pituitary was increased after testosterone treatment in the castrated mice, whereas, the expression level in the hypothalamus was significantly decreased after the treatment with testosterone. The in vitro experiment to elucidate the direct effect of testosterone on NUCB2 mRNA expression showed that NUCB2 mRNA expression was significantly decreased with testosterone in cultured hypothalamus tissue, but increased with testosterone in cultured pituitary gland. The present study demonstrated that nesfatin-1/NUCB2 was highly expressed in the male mouse pituitary and was regulated by testosterone. This data suggests that reproductive-endocrine regulation through hypothalamus-pituitary-testis axis may contribute to NUCB2 mRNA expression in the mouse hypothalamus and pituitary gland. PMID:28484746
Vongas, John G; Al Hajj, Raghid
2017-06-01
A contribution to a special issue on Hormones and Human Competition. We investigated the effects of competition on men's testosterone levels and assessed whether androgen reactivity was associated with subsequent emotion recognition and reactive and proactive aggression. We also explored whether personalized power (p Power) moderated these relationships. In Study 1, 84 males competed on a number tracing task and interpreted emotions from facial expressions. In Study 2, 72 males competed on the same task and were assessed on proactive and reactive aggression. In both studies, contrary to the biosocial model of status (Mazur, 1985), winners' testosterone levels decreased significantly while losers' levels increased, albeit not significantly. Personalized power moderated the effect of competition outcome on testosterone change in both studies. Using the aggregate sample, we found that the effect of decreased testosterone levels among winners (compared to losers) was significant for individuals low in p Power but not for those with medium or high p Power. Testosterone change was positively related to emotion recognition, but unrelated to either aggression subtype. The testosterone-mediated relationship between winning and losing and emotion recognition was moderated by p Power. In addition, p Power moderated the direct (i.e., non-testosterone mediated) path between competition outcome and emotion recognition and both types of aggression: high p-Power winners were more accurate at deciphering others' emotions than high p-Power losers. Finally, among high p-Power men, winners aggressed more proactively than losers, whereas losers aggressed more reactively than winners. Collectively, these studies highlight the importance of implicit power motivation in modulating hormonal, cognitive, and behavioral outcomes arising from human competition. Copyright © 2017 Elsevier Inc. All rights reserved.
Effects of testosterone administration on liver structure and function in aging rats.
Nucci, Ricardo Aparecido Baptista; Teodoro, Ana Caroline de Souza; Krause Neto, Walter; Silva, Wellington de Assis; de Souza, Romeu Rodrigues; Anaruma, Carlos Alberto; Gama, Eliane Florencio
2017-06-01
Aging males have a decrease in testosterone levels, by which the testosterone treatment may influence in a negatively fashion the liver. This study aimed to analyze the effects of aging with or without testosterone administration on the liver components of animals. Wistar rats were divided into three groups: 20 months' group (G20), 24 months' group (G24), group treated with testosterone for 16 weeks (GT). All groups were sacrificed at 24 months except for G20 that was sacrificed at 20 months. Aging and testosterone treatment alters the body weight (BW), liver weight (LW) and relative liver weight. Besides, testosterone increased the mitogen capacity of hepatocytes. Nonetheless, we reinforce the negative effects of testosterone on old animals' liver as chronic hepatic congestion and/or cholestasis. In addition, we observed that testosterone plays an important role on hepatic glycogen stores. Our study showed many implications for the knowledge about the effects of aging with or without testosterone administration on old animals' liver.
Testosterone and Jamaican Fathers : Exploring Links to Relationship Dynamics and Paternal Care.
Gray, Peter B; Reece, Jody; Coore-Desai, Charlene; Dinall, Twana; Pellington, Sydonnie; Samms-Vaughan, Maureen
2017-06-01
This paper investigates relationships between men's testosterone and family life in a sample of approximately 350 Jamaican fathers of children 18-24 months of age. The study recognizes the role of testosterone as a proximate mechanism coordinating and reflecting male life history allocations within specific family and cultural contexts. A sample of Jamaican fathers and/or father figures reported to an assessment center for an interview based on a standardized questionnaire and provided a saliva sample for measuring testosterone level. Outcomes measured include subject demographics such as age and relationship status as well as partnership quality and sexuality and paternal attitudes and behavior. The variation in these fathers' relationship status (e.g., married co-residential fathers, fathers in new non-residential relationships) was not associated with men's testosterone. Too few stepfathers participated to enable a direct test of the prediction that stepfathers would have higher testosterone than biological fathers, although fathers who reported living with partners' (but not his own) children did not have higher testosterone than fathers not reporting residing with a non-biological child. Fathers' relationship quality was negatively related to their testosterone. Measures of paternal attitudes and behavior were not related to fathers' testosterone. Consistent with previous ethnography, this sample of Jamaican fathers exhibited variable life history profiles, including residential status. We discuss why fathers' relationship quality was found to be negatively related to their testosterone level, but other predictions were not upheld.
Roberts, Mark L; Buchanan, Katherine L; Evans, Matthew R; Marin, Raul H; Satterlee, Daniel G
2009-10-01
The immunocompetence handicap hypothesis (ICHH) suggests that the male sex hormone testosterone has a dual effect; it controls the development and expression of male sexually selected signals, and it suppresses the immune system. Therefore only high quality males are able to fully express secondary sexual traits because only they can tolerate the immunosuppressive qualities of testosterone. A modified version of the ICHH suggests that testosterone causes immunosuppression indirectly by increasing the stress hormone corticosterone (CORT). Lines of Japanese quail (Coturnix japonica) selected for divergent responses in levels of plasma CORT were used to test these hypotheses. Within each CORT response line (as well as in a control stock) we manipulated levels of testosterone in castrated quail by treatment with zero (sham), low or high testosterone implants, before testing the birds' humoral immunity and phytohaemagglutinin (PHA)-induced immune response, as well as body condition. The PHA-induced response was not significantly affected by CORT selected line, testosterone treatment or their interaction. There was, however, a significant effect of CORT line on humoral immunity in that the control birds exhibited the greatest antibody production, but there was no significant effect of testosterone manipulation on humoral immunity. The males in the sham implant treatment group had significantly greater mass than the males in the high testosterone group, suggesting a negative effect of high testosterone on general body condition. We discuss these results in the context of current hypotheses in the field of sexual selection.
Liu, Tao; Zhao, Han; Wang, Jianfeng; Shu, Xin; Gao, Yuan; Mu, Xiaoli; Gao, Fei; Liu, Hongbin
2017-11-01
The present study aimed to identify the molecular mechanisms underlying the effects of the fructose‑1,6‑bisphosphatase 1 (FBP1) signaling pathway within normal follicle development and in hyperandrogenism‑induced abnormal follicle growth. To achieve this, murine primary follicles, granulosa cells (GCs) and theca‑interstitial cells (TICs) were isolated, cultured in vitro and treated with a high concentration of androgens. A concentration of 1x10‑5 mol/l testosterone was considerable to induce hyperandrogenism by MTT assay. All cells were divided into four groups, as follows: Control group, testosterone group, androgen receptor antagonist‑flutamide group and flutamide + testosterone group. Flutamide was used in the present study as it blocks the effects of the androgen receptor. The mRNA expression levels of FBP1 were detected using reverse transcription‑quantitative polymerase chain reaction. The expression levels and localization of FBP1 were analyzed by western blot analysis and immunofluorescence staining. The experimental results demonstrated that androgen presence stimulated follicle development, whereas excessive testosterone inhibited development. FBP1 was identified as being mainly expressed in follicles; FBP1 protein was significantly expressed in GCs of the 14‑day‑cultured follicle, as well as in the cytoplasm and nuclei of GCs and TICs in vitro. Testosterone increased FBP1 expression during a specific range of testosterone concentrations. Testosterone increased the expression of FBP1 within GCs. Furthermore, FBP1 and phosphoenolpyruvate carboxykinase 1 (PCK1) mRNA expression was increased in GCs treated with testosterone, whereas forkhead box protein O1 (FOXO1) and peroxisome proliferator‑activated receptor γ coactivator‑1α mRNA expression was significantly decreased in the testosterone group. In TICs, testosterone and flutamide inhibited the mRNA expression levels of FOXO1 and glucose‑6‑phosphatase enzyme, and promoted the expression of PCK1. These results suggested that the FBP1 signaling pathway may serve an important role in normal follicle growth and hyperandrogenism‑induced abnormal development, which may be associated with abnormal glucose metabolism induced by high concentrations of testosterone.
Plasma isoflavones in Malaysian men according to vegetarianism and by age.
Hod, Rafidah; Kouidhi, Wided; Ali Mohd, Mustafa; Husain, Ruby
2016-01-01
Epidemiological studies indicate lower prevalences of breast and prostate cancers and cardiovascular disease in Southeast Asia where vegetarianism is popular and diets are traditionally high in phytoestrogens. This study assessed plasma isoflavones in vegetarian and non-vegetarian Malaysian men according to age. Daidzein, genistein, equol (a daidzein metabolite), formononetin, biochanin A, estrone, estradiol and testosterone were measured by validated liquid chromatography tandem mass spectrometry (LCMSMS). Plasma isoflavone and sex hormone concentrations were measured in 225 subjects according to age (18-34, 35-44 and 45-67 years old). In all age groups, vegetarians had a higher concentration of circulating isoflavones compared with non-vegetarians especially in the 45-67 year age group where all isoflavones except equol, were significantly higher in vegetarians compared with omnivores. By contrast, the 18-34 year group had a significantly higher concentration of daidzein in vegetarians and significantly higher testosterone and estrone concentrations compared with non-vegetarians. In this age group there were weak correlations between estrone, estradiol and testosterone with some of the isoflavones. This human study provides the first Malaysian data for the phytoestrogen status of vegetarian and nonvegetarian men.
Pascual-Sagastizabal, Eider; Azurmendi, Aitziber; Braza, Francisco; Vergara, Ana I; Cardas, Jaione; Sánchez-Martín, José R
2014-01-01
This study examines the relationship between parenting style, androgen levels, and measures of physical and indirect aggression. Peer ratings of aggression were obtained from 159 eight-year-old children (89 boys and 70 girls). Parenting styles (authoritative, authoritarian or permissive) were assessed using the Parenting Styles and Dimensions Questionnaire (PSDQ).Saliva samples were obtained from children and assayed for testosterone and androstenedione concentrations. A regression analysis revealed that high testosterone levels were associated with a higher level of physical aggression in boys with authoritarian mothers. Testosterone was also found to moderate the relationship between father's authoritarian parenting and physical aggression in girls, with both moderate and high levels being significant. In relation to indirect aggression, moderate and high levels of testosterone were associated with higher levels of this type of aggression in girls with permissive mothers. Our results highlight the importance of taking into account the interaction of biological and psychosocial variables when investigating aggressive behavior. © 2014 Wiley Periodicals, Inc.
Udoh, P B; Udoh, F V; Umoren, E B; James, U W; Okeke, C P; Agwu, B
2009-06-01
Activity of alkaloid extract of caricapryl-99 seeds [Carica papaya Linn seeds] on the serum levels of steroid hormones was studied in adult male albino rats. Three tolerated doses obtained from the graph of percentage toxicity [10, 50 and 150 mg/kg] were separately administered orally, daily for three days to three groups of male rats [n=5] while group four of 5 rats received the vehicle [corn oil] as control. The results showed that 10 mg/kg/d caused increase serum levels of FSH and estrogen but decrease in the serum levels of LH and testosterone compared to control; 50 mg/kg/d elevated the serum levels of FSH, estrogen but inhibited testosterone; while 150 mg/kg/d pretreatments caused a significant decrease [p<0.01] in the serum levels of FSH, LH and testosterone. The results suggest that caricapryl-99 treatment inhibited the serum level of the androgen, testosterone which might result in a male infertility.
Eriksson, C J P; Etelälahti, T J; Apter, S J
2017-06-01
A number of studies have shown that stress and an activated hypothalamic-pituitary-adrenal (HPA) axis are associated with increased voluntary alcohol drinking. Recently, associations have been found between activated HPA and hypothalamic-pituitary-gonadal (HPG) axes in alcohol-preferring AA and non-preferring ANA, F2 (crossbred second generation from original AA and ANA), and Wistar rats. The aim of the present study has been to determine the role of corticosterone and alcohol-related testosterone-effects in subsequent alcohol drinking in AA, ANA, F2 and Wistar rats. The present study comprises of four substudies presenting new analyses of existing data, by which correlations between basal corticosterone levels, changes in testosterone levels during alcohol intoxications and subsequent voluntary alcohol consumption are investigated. The results displayed positive correlations between basal corticosterone levels and subsequent alcohol-mediated testosterone elevations, which was positively associated with voluntary alcohol consumption. The results also showed a negative correlation between basal corticosterone levels and alcohol-mediated testosterone decreases, which was negatively associated with alcohol consumption. In conclusion, the present study displays novel results, according to which the HPA axis, one hand, relates to testosterone elevation (potentially causing and/or strengthening reinforcement) during alcohol intoxication, which in turn may relate to higher voluntary alcohol consumption (AA rats). Vice versa, the HPA axis may also relate to alcohol-mediated testosterone decrease (causing testosterone reduction and disinforcement) and low-alcohol drinking (ANA, F2 and Wistar rats). In addition, the present results showed that alcohol-mediated testosterone changes may also, independently of the HPA axis, correlate with voluntary alcohol drinking, which indicate the impact of genetic factors. Thus, the role of the HPA-axis may be more related to situational stress than to intrinsic factors. In further studies, it should be investigated, whether the present results also apply to stress and human alcohol drinking. Copyright © 2017 Elsevier Inc. All rights reserved.
Role of parenteral testosterone in hypospadias: A study from a teaching hospital in India
Ahmad, Reyaz; Chana, Rajendra Singh; Ali, Syed Manazir; Khan, Shehtaj
2011-01-01
Objectives: To evaluate the effect of parenteral testosterone on penile length, preputial skin and side effects in patients with hypospadias. Materials and Methods: 23 patients with hypospadias were included in this study. An oily solution, each ml of which contained testosterone propionate 25 mg, and testosterone enanthate 110 mg, equivalent to 100 mg of testosterone was given deep intramuscularly 4, 3 and 2 weeks before reconstructive surgery at the dose of 2 mg/kg body weight. Increase in penile length, transverse preputial diameter, and diameter at the base of penis were noted. Basal testosterone levels were obtained before the institution of therapy and on the day of operation. In addition, side effect such as development of pubic hair and delay in bone age was noted. Results: Following parenteral testosterone administration, the mean increase in penile length, transverse preputial diameter and diameter at the base of penis was 1.35±0.40 cm (P<0.001), 1.40±0.47 cm (P<0.001), and 0.72±0.47 cm (P<0.001), respectively. Serum testosterone level after injection was well within normal range for that age. Minimal side effects were noted in form of development of fine pubic hair. Conclusion: We conclude that parenteral testosterone can be safely used to improve the surgical outcome of hypospadias repair. PMID:21976926
Relationship between Carotenoids, Retinol, and Estradiol Levels in Older Women
Maggio, Marcello; de Vita, Francesca; Lauretani, Fulvio; Bandinelli, Stefania; Semba, Richard D.; Bartali, Benedetta; Cherubini, Antonio; Cappola, Anne R.; Ceda, Gian Paolo; Ferrucci, Luigi
2015-01-01
Background. In vitro evidence suggests anti-estrogenic properties for retinol and carotenoids, supporting a chemo-preventive role of these phytochemicals in estrogen-dependent cancers. During aging there are significant reductions in retinol and carotenoid concentrations, whereas estradiol levels decline during menopause and progressively increase from the age of 65. We aimed to investigate the hypothesis of a potential relationship between circulating levels of retinol, carotenoids, and estradiol (E2) in a cohort of late post-menopausal women. Methods. We examined 512 women ≥ 65 years from the InCHIANTI study. Retinol, α-caroten, β-caroten, β-criptoxantin, lutein, zeaxanthin, and lycopene levels were assayed at enrollment (1998–2000) by High-Performance Liquid Chromatography. Estradiol and testosterone (T) levels were assessed by Radioimmunometry (RIA) and testosterone-to-estradiol ratio (T/E2), as a proxy of aromatase activity, was also calculated. General linear models adjusted for age (Model 1) and further adjusted for other confounders including Body Mass Index (BMI) BMI, smoking, intake of energy, lipids, and vitamin A; C-Reactive Protein, insulin, total cholesterol, liver function, and testosterone (Model 2) were used to investigate the relationship between retinol, carotenoids, and E2 levels. To address the independent relationship between carotenoids and E2 levels, factors significantly associated with E2 in Model 2 were also included in a fully adjusted Model 3. Results. After adjustment for age, α-carotene (β ± SE = −0.01 ± 0.004, p = 0.02) and β-carotene (β ± SE = −0.07 ± 0.02, p = 0.0007) were significantly and inversely associated with E2 levels. α-Carotene was also significantly and positively associated with T/E2 ratio (β ± SE = 0.07 ± 0.03, p = 0.01). After adjustment for other confounders (Model 2), the inverse relationship between α-carotene (β ± SE = −1.59 ± 0.61, p = 0.01), β-carotene (β ± SE = −0.29 ± 0.08, p = 0.0009), and E2 persisted whereas the relationship between α-carotene and T/E2 ratio was attenuated (β ± SE = 0.22 ± 0.12, p = 0.07). In a fully adjusted model (Model 3), only β-carotene (β ± SE = −0.05 ± 0.02, p = 0.03) was significantly and inversely associated with E2 levels independent of α-carotene. No association was found between retinol, total non-pro-vitamin A carotenoids, lutein, zeaxanthin, and lycopene, and E2 levels. Conclusions: In older women, β-carotene levels are independently and inversely associated with E2. PMID:26251919
Relationship between Carotenoids, Retinol, and Estradiol Levels in Older Women.
Maggio, Marcello; de Vita, Francesca; Lauretani, Fulvio; Bandinelli, Stefania; Semba, Richard D; Bartali, Benedetta; Cherubini, Antonio; Cappola, Anne R; Ceda, Gian Paolo; Ferrucci, Luigi
2015-08-05
In vitro evidence suggests anti-estrogenic properties for retinol and carotenoids, supporting a chemo-preventive role of these phytochemicals in estrogen-dependent cancers. During aging there are significant reductions in retinol and carotenoid concentrations, whereas estradiol levels decline during menopause and progressively increase from the age of 65. We aimed to investigate the hypothesis of a potential relationship between circulating levels of retinol, carotenoids, and estradiol (E2) in a cohort of late post-menopausal women. We examined 512 women ≥ 65 years from the InCHIANTI study. Retinol, α-caroten, β-caroten, β-criptoxantin, lutein, zeaxanthin, and lycopene levels were assayed at enrollment (1998-2000) by High-Performance Liquid Chromatography. Estradiol and testosterone (T) levels were assessed by Radioimmunometry (RIA) and testosterone-to-estradiol ratio (T/E2), as a proxy of aromatase activity, was also calculated. General linear models adjusted for age (Model 1) and further adjusted for other confounders including Body Mass Index (BMI) BMI, smoking, intake of energy, lipids, and vitamin A; C-Reactive Protein, insulin, total cholesterol, liver function, and testosterone (Model 2) were used to investigate the relationship between retinol, carotenoids, and E2 levels. To address the independent relationship between carotenoids and E2 levels, factors significantly associated with E2 in Model 2 were also included in a fully adjusted Model 3. After adjustment for age, α-carotene (β ± SE = -0.01 ± 0.004, p = 0.02) and β-carotene (β ± SE = -0.07 ± 0.02, p = 0.0007) were significantly and inversely associated with E2 levels. α-Carotene was also significantly and positively associated with T/E2 ratio (β ± SE = 0.07 ± 0.03, p = 0.01). After adjustment for other confounders (Model 2), the inverse relationship between α-carotene (β ± SE = -1.59 ± 0.61, p = 0.01), β-carotene (β ± SE = -0.29 ± 0.08, p = 0.0009), and E2 persisted whereas the relationship between α-carotene and T/E2 ratio was attenuated (β ± SE = 0.22 ± 0.12, p = 0.07). In a fully adjusted model (Model 3), only β-carotene (β ± SE = -0.05 ± 0.02, p = 0.03) was significantly and inversely associated with E2 levels independent of α-carotene. No association was found between retinol, total non-pro-vitamin A carotenoids, lutein, zeaxanthin, and lycopene, and E2 levels. In older women, β-carotene levels are independently and inversely associated with E2.
Garde, E; Pérez, G E; Vanderstichel, R; Dalla Villa, P F; Serpell, J A
2016-01-01
Population management of free-roaming domestic dogs (Canis lupus familiaris) is of interest due to the threat these animals pose to people, other animals and the environment. Current sterilization procedures for male dogs include surgical and chemical methods. However, little is known about how these procedures affect their behavior. The primary objective of this study was to investigate changes in selected behaviors following chemical and surgical sterilization in a male free-roaming dog (FRD) population in southern Chile. We also examined the association between serum testosterone levels and behaviors thought to be influenced by circulating androgens. A total of 174 dogs were randomly assigned to either a surgical or chemical sterilization group, or a control group. At the onset of the intervention period, 119 dogs remained and 102 dogs successfully completed the study. Each dog was monitored pre- and post-intervention using video recordings, GPS collars, and blood samples for the measurement of testosterone. Analysis of behavior revealed that surgically castrated dogs showed no reduction of sexual activity or aggression when compared to their pre-intervention behavior. Chemically sterilized dogs showed a statistically significant increase in dog-directed aggression, but no change in sexual activity. There was no change in home range size in any groups between the pre- and post-intervention measurement. We found no consistent association between levels of serum testosterone concentration and behavioral changes in any of the groups. This study presents the first detailed behavioral observations following surgical and chemical sterilization in male FRDs. The information generated is highly relevant to communities struggling with the control of FRDs. Complementary studies to further our understanding of the effects of male sterilization on the behavioral and reproductive dynamics of FRD populations are needed. Copyright © 2015 Elsevier B.V. All rights reserved.
Pulmonary exposure to carbonaceous nanomaterials and sperm quality.
Skovmand, Astrid; Jacobsen Lauvås, Anna; Christensen, Preben; Vogel, Ulla; Sørig Hougaard, Karin; Goericke-Pesch, Sandra
2018-01-31
Semen quality parameters are potentially affected by nanomaterials in several ways: Inhaled nanosized particles are potent inducers of pulmonary inflammation, leading to the release of inflammatory mediators. Small amounts of particles may translocate from the lungs into the lung capillaries, enter the systemic circulation and ultimately reach the testes. Both the inflammatory response and the particles may induce oxidative stress which can directly affect spermatogenesis. Furthermore, spermatogenesis may be indirectly affected by changes in the hormonal milieu as systemic inflammation is a potential modulator of endocrine function. The aim of this study was to investigate the effects of pulmonary exposure to carbonaceous nanomaterials on sperm quality parameters in an experimental mouse model. Effects on sperm quality after pulmonary inflammation induced by carbonaceous nanomaterials were investigated by intratracheally instilling sexually mature male NMRI mice with four different carbonaceous nanomaterials dispersed in nanopure water: graphene oxide (18 μg/mouse/i.t.), Flammruss 101, Printex 90 and SRM1650b (0.1 mg/mouse/i.t. each) weekly for seven consecutive weeks. Pulmonary inflammation was determined by differential cell count in bronchoalveolar lavage fluid. Epididymal sperm concentration and motility were measured by computer-assisted sperm analysis. Epididymal sperm viability and morphological abnormalities were assessed manually using Hoechst 33,342/PI flourescent and Spermac staining, respectively. Epididymal sperm were assessed with regard to sperm DNA integrity (damage). Daily sperm production was measured in the testis, and testosterone levels were measured in blood plasma by ELISA. Neutrophil numbers in the bronchoalveolar fluid showed sustained inflammatory response in the nanoparticle-exposed groups one week after the last instillation. No significant changes in epididymal sperm parameters, daily sperm production or plasma testosterone levels were found. Despite the sustained pulmonary inflammatory response, an eight week exposure to graphene oxide, Flammruss 101, Printex 90 and the diesel particle SRM1650b in the present study did not appear to affect semen parameters, daily sperm production or testosterone concentration in male NMRI mice.
Stephens, Mary Ann C.; Mahon, Pamela B.; McCaul, Mary E.; Wand, Gary S.
2016-01-01
Summary Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis influences the risk for developing stress-related disorders. Sex-dependent differences in the HPA axis stress response are believed to contribute to the different prevalence rates of stress-related disorders found in men and women. However, studies examining the HPA axis stress response have shown mixed support for sex differences, and the role of endogenous sex hormones on HPA axis response has not been adequately examined in humans. This study utilized the largest sample size to date to analyze the effects of biological sex and sex hormones on HPA axis social stress responses. Healthy, 18- to 30- year-old community volunteers (N=282) completed the Trier Social Stress Test (TSST), a widely used and well-validated stress-induction laboratory procedure. All women (n=135) were tested during the follicular phase of their menstrual cycle (when progesterone levels are most similar to men). Adrenocorticotropic hormone (ACTH) and cortisol measures were collected at multiple points throughout pre- and post-TSST. Testosterone and progesterone (in men) and progesterone and estradiol (in women) were determined pre-TSST. Following the TSST, men had greater ACTH and cortisol levels than women. Men had steeper baseline-to-peak and peak-to-end ACTH and cortisol response slopes than women; there was a trend for more cortisol responders among men than women. Testosterone negatively correlated with salivary cortisol response in men, while progesterone negatively correlated with ACTH and cortisol responses in women. These data confirm that men show more robust activation of the HPA axis response to the TSST than do women in the follicular phase of the menstrual cycle. Testosterone results suggest an inhibitory effect on HPA axis reactivity in men. Progesterone results suggest an inhibitory effect on HPA axis reactivity in women. Future work is needed to explain why men mount a greater ACTH and cortisol response to the TSST than do women during the follicular phase of the menstrual cycle. PMID:26773400
Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua
2016-01-01
Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg−1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo. PMID:26608944
Ooishi, Yuuki
2018-01-01
A sound-induced sympathetic tone has been used as an index for orienting responses to auditory stimuli. The resting testosterone/cortisol ratio is a biomarker of social aggression that drives an approaching behavior in response to environmental stimuli, and a higher testosterone level and a lower cortisol level can facilitate the sympathetic response to environmental stimuli. Therefore, it is possible that the testosterone/cortisol ratio is correlated with the sound-induced sympathetic tone. The current study investigated the relationship between the resting testosterone/cortisol ratio and vasoconstriction induced by listening to sound stimuli. Twenty healthy males aged 29.0 ± 0.53 years (mean ± S.E.M) participated in the study. They came to the laboratory for 3 days and listened to one of three types of sound stimuli for 1 min on each day. Saliva samples were collected for an analysis of salivary testosterone and cortisol levels on the day of each experiment. After the collecting the saliva sample, we measured the blood volume pulse (BVP) amplitude at a fingertip. Since vasoconstriction is mediated by the activation of the sympathetic nerves, the strength of the reduction in BVP amplitude at a fingertip was called the BVP response (finger BVPR). No difference was observed between the sound-induced finger BVPR for the three types of sound stimuli (p = 0.779). The correlation coefficient between the sound-induced finger BVPR and the salivary testosterone/cortisol ratio within participants was significantly different from no correlation (p = 0.011) and there was a trend toward a significance in the correlation between the sound-induced finger BVPR and the salivary testosterone/cortisol ratio between participants (r = 0.39, p = 0.088). These results suggest that the testosterone/cortisol ratio affects the difference in the sound-evoked sympathetic response. PMID:29559922
Ooishi, Yuuki
2018-01-01
A sound-induced sympathetic tone has been used as an index for orienting responses to auditory stimuli. The resting testosterone/cortisol ratio is a biomarker of social aggression that drives an approaching behavior in response to environmental stimuli, and a higher testosterone level and a lower cortisol level can facilitate the sympathetic response to environmental stimuli. Therefore, it is possible that the testosterone/cortisol ratio is correlated with the sound-induced sympathetic tone. The current study investigated the relationship between the resting testosterone/cortisol ratio and vasoconstriction induced by listening to sound stimuli. Twenty healthy males aged 29.0 ± 0.53 years (mean ± S.E.M) participated in the study. They came to the laboratory for 3 days and listened to one of three types of sound stimuli for 1 min on each day. Saliva samples were collected for an analysis of salivary testosterone and cortisol levels on the day of each experiment. After the collecting the saliva sample, we measured the blood volume pulse (BVP) amplitude at a fingertip. Since vasoconstriction is mediated by the activation of the sympathetic nerves, the strength of the reduction in BVP amplitude at a fingertip was called the BVP response (finger BVPR). No difference was observed between the sound-induced finger BVPR for the three types of sound stimuli ( p = 0.779). The correlation coefficient between the sound-induced finger BVPR and the salivary testosterone/cortisol ratio within participants was significantly different from no correlation ( p = 0.011) and there was a trend toward a significance in the correlation between the sound-induced finger BVPR and the salivary testosterone/cortisol ratio between participants ( r = 0.39, p = 0.088). These results suggest that the testosterone/cortisol ratio affects the difference in the sound-evoked sympathetic response.
Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua
2016-01-01
Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo.
Ramaswamy, S; Pohl, C R; McNeilly, A S; Winters, S J; Plant, T M
1998-08-01
In higher primates, FSH secretion appears to be regulated by a control system consistent with that described by the classical inhibin hypothesis. The purpose of the present experiment was to examine the time course of inhibin's action to suppress FSH secretion in the intact adult male rhesus monkey. To this end, five adult males implanted with indwelling venous catheters and exhibiting typical episodic patterns of LH and testosterone (T) secretion received a 4-day i.v. infusion of recombinant human (rh) inhibin A (832 ng/h x kg) followed, after a 4-week interval, by vehicle infusion of similar duration. Changes in circulating FSH concentrations during the inhibin and vehicle infusions were determined using a sensitive homologous macaque RIA, whereas enzyme-linked immunosorbent assays were employed to track inhibin A, inhibin B, and inhibin pro-alpha-C levels during the experiment. Normal pulsatile activity in the hypothalamic-pituitary-Leydig cell axis was confirmed by monitoring changes in circulating concentrations of LH and T in 12-h windows of sequential blood collection (1200-2400 h; every 20 min) before, during, and after the rh inhibin A and vehicle infusions. Although infusion of rh inhibin A, which led to a 12 ng/ml square wave increment in circulating levels of this inhibin dimer, produced a marked decline in circulating FSH concentrations, significant suppression of the secretion of this gonadotropin was not manifest until 54 h after initiation of the infusion. Despite the marked decline in FSH secretion during the last 24 h of the 4-day infusion of recombinant hormone, circulating inhibin B and pro-alpha-C concentrations were maintained at preinfusion control levels (1 ng/ml). The finding that imposition of an exaggerated circulating inhibin signal led to suppression of FSH secretion in the male monkey only after 2 days of exposure to the hormone indicates that in this species the feedback action of testicular inhibin on FSH secretion is heavily lagged. Moreover, as the decrease in FSH did not lead to changes in native inhibin secretion, it seems reasonable to propose that the FSH-inhibin feedback loop that governs testicular function in higher primates operates with considerable hysteresis at both the pituitary and gonadal levels. The failure of dramatically elevated inhibin A levels to influence the pulsatile secretion of LH in the monkey reinforces the idea that in this species the pituitary action of testicular inhibin is specific for FSH and does not involve modulation of GnRH receptor levels.
Liu, C C; Lee, Y C; Tsai, V F S; Cheng, K H; Wu, W J; Bao, B Y; Huang, C N; Yeh, H C; Tsai, C C; Wang, C J; Huang, S P
2015-09-01
Testosterone has been found to play important roles in men's sexual function. However, the effects of testosterone can be modulated by androgen receptor (AR) CAG repeat polymorphism. It could also contribute to the risk of erectile dysfunction (ED). The aim of this study is to evaluate the interaction of serum testosterone levels and AR CAG repeat polymorphism on the risk of ED in aging Taiwanese men. This cross-sectional data of Taiwanese men older than 40 years were collected from a free health screening held between August 2010 and August 2011 in Kaohsiung city, Taiwan. All participants completed a health questionnaires included five-item version of the International Index of Erectile Function (IIEF-5) and the International Prostate Symptoms Score, received a detailed physical examination and provided 20 cm3 whole blood samples for biochemical and genetic evaluation. The IIEF-5 was used to evaluate ED. Serum albumin, total testosterone (TT), and sex hormone-binding globulin levels were measured. Free testosterone level was calculated. AR gene CAG repeat polymorphism was determined by direct sequencing. Finally, 478 men with the mean age of 55.7 ± 4.8 years were included. When TT levels were above 330 ng/dL, the effect of testosterone level on erectile function seemed to reach a plateau and a significantly negative correlation between AR CAG repeat length and the score of IIEF-5 was found (r = -0.119, p = 0.034). After adjusting for other covariates, the longer AR CAG repeat length was still an independent risk factor for ED in subjects with TT above 330 ng/dL (p = 0.006), but not in TT of 330 ng/dL or below. In conclusion, both serum testosterone levels and AR CAG repeat polymorphism can influence erectile function concomitantly. In subjects with normal TT concentration, those with longer AR CAG repeat lengths have a higher risk of developing ED. © 2015 American Society of Andrology and European Academy of Andrology.
Hadji, P; Kauka, A; Bauer, T; Tams, J; Hasenburg, A; Kieback, D G
2012-10-01
The aim of this study was to compare the effects of exemestane and tamoxifen on hormone levels in postmenopausal patients with hormone receptor-positive breast cancer within a Germany substudy of the Tamoxifen Exemestane Adjuvant Multinational (TEAM) trial. Within the TEAM trial, patients were randomized to receive adjuvant treatment with exemestane for 5 years or tamoxifen for 2.5-3 years followed by exemestane for 2-2.5 years. Serum levels of testosterone, dehydroepiandrosterone sulfate (DHEAS), sex hormone binding globulin (SHBG), follicle stimulating hormone (FSH) and parathyroid hormone (PTH)-intact were measured at screening and after 3, 6 and 12 months of treatment. Data on hormone levels were available from 63 patients in the tamoxifen arm and 68 patients in the exemestane arm. Treatment with exemestane resulted in decreases from baseline in SHBG and PTH-intact levels, and increases from baseline in testosterone, DHEAS and FSH levels. Tamoxifen treatment resulted in increases from baseline in SHBG and PTH-intact, whereas levels of testosterone and FSH decreased and DHEAS levels did not change. At all time points assessed, the absolute change from baseline was significantly different between tamoxifen and exemestane for testosterone, SHBG, FSH and PTH-intact (all p < 0.0001). Exemestane and tamoxifen had statistically significantly different effects on hormone levels, including testosterone, SHBG, FSH and PTH-intact.
AB19. Testosterone replacement therapy: how safe is it?
Goldenberg, Larry
2014-01-01
Testosterone has a ubiquitous role in the male body and the importance of a decline in testosterone levels has wide ranging impact on: regulation of gonadal function, prostate development and growth, libido, cerebral function, behavior, mood, muscle mass, liver function, lipid regulation, bone formation, atherogenesis, erythropoiesis, hair growth and immune function. What the minimum required level of serum testosterone for the optimal health of each of these areas, nor whether each organ system’s biological response to increasing or decreasing testosterone levels follows a ‘dose-response’, ‘threshold’ or other behaviour is unclear. Late-onset hypogonadism (also known as age-associated testosterone deficiency syndrome) is a syndrome associated with advancing age and characterized by a spectrum of symptoms and a biochemical deficiency in serum testosterone levels below the young healthy adult male reference range (280-300 ng/dL; 9.8-10.4 nmol/L- Note: this level may vary in different laboratories). The decrease in serum testosterone levels seems to be a gradual, age-related process resulting in an approximate 1-2% annual decline after age 30 years, with a steep decline in bioavailable and free testosterone levels. The findings Baltimore Longitudinal Study of Aging demonstrated that 30% of men in their eighth have total testosterone values in the hypogonadal range (that is between 200 and 400 ng/dL), and 50% have low free testosterone values (5-9 ng/dL; 0.17-0.31 nmol/L). An estimated 500,000 new cases of late-onset hypogonadism occur annually in the USA, with similar levels reported worldwide. Testosterone deficiency has marked physiological and clinical effects on men in middle age and beyond. With subnormal testosterone levels, the potential positive benefits of TRT on factors such as muscle mass, libido or erectile function are likely a dose-response phenomena, and should be considered differently than the threshold impact on the prostate. The controversies surrounding testosterone replacement therapy (TRT) have been addressed in the past few years. Although the androgenic effects of TRT on normal and malignant prostate cells have been studied for over 70 years, little clinical prospective research exists on the physiological responses of prostate tissues to a wide range of serum testosterone levels. The early, well-designed in vivo studies formed the basis of the concept that testosterone has a threshold or saturation level in all types of androgen-dependent prostate cells. That is, the stimulatory effects of androgens on the prostate reach a point within physiological serum levels above which they no longer have any proliferative effect and serum levels of testosterone and dihydrotestosterone can decrease substantially in both the eugonadal and hypogonadal states without affecting the amount of androgen within the nucleus of the cell. At a certain threshold level (possibly ‘castrate’ level), the intranuclear level of androgen will begin to decrease and the appropriate physiological changes will be triggered. Questions remain as to whether results from experimental studies in the rat can be extrapolated to the situation in humans. Is the human prostate subject to the same homeostatic constraints as has been so well defined in animal experiments, and if so, what is the threshold or saturation level for maximal intracellular androgens and physiological responses in man? The sensitivity of an individual to varying levels of testosterone is also influenced by his genetic makeup, particularly polymorphisms in the androgen receptor, and other upstream signaling and downstream metabolic events, including diabetes mellitus and obesity. Despite decades of research, no compelling evidence exists that increasing testosterone beyond this threshold level has a causative role in prostate cancer, or indeed changes the biology of the disease. Notwithstanding this, the reluctance to utilize testosterone replacement has been incorporated into urological dogma and is largely responsible for the US FDA’s continuing caution about the relationship between therapy and initiation or progression of prostate cancer. Recent international concern has arisen on the potential negative impact of TRT on the cardiovascular system, specifically MI and CVA. This is based on the results of a clinical trial and two observational studies. The first study to identify an association was the Testosterone in Older Men (TOM) trial designed to evaluate the effect of a T gel on muscle strength and functionality in an elderly population. The study did show an increase in upper and lower limb strength but was terminated prematurely due to an increased cardiovascular event rate in men receiving T. But because of the low event rate, the fact that many men reached supraphysiologic levels of serum T and the fact that the study was not designed with any specific cardiovascular endpoints in mind, it is difficult to conclude from this study that T therapy places men at increased risk of CVS disease. The next publication by Vigen et al. was a retrospective, non-randomized, observational analysis of 8,709 men, 61 to 64 years, who had undergone coronary angiography in the VA system with a low serum total testosterone (<300 ng/dL), looking at the CV events after having filled a prescription for TRT, comparing to untreated patients. The actual CVS event rate was twice as high for the untreated men (21.2% vs. 10.1%) but after complex statistical modeling the number of events in the treated men tripled. This study has been widely discredited because of serious flaws. For example, many of the treated men did not achieve normal levels, most men did not fill their scripts for the full 4-year duration of the study, and almost 3,000 men who received TRT prior to angiography were excluded so all men began in the ‘no TRT’ group. Most importantly, the authors inexplicably excluded 1,132 men who suffered stroke or heart attack prior to receiving a testosterone prescription. These men all had events during the study period and all should have been included in the no-testosterone group. This would have increased the rate of events in the no-testosterone group by 71%, likely reversing the results. It is impossible to conclude from this study that testosterone prescriptions increase rates of cardiovascular events. In a third population-based retrospective, non-randomized, observational study (insurance claims) of a cohort of 55,593 men, Finkle and colleagues evaluated the rate of non fatal MI in the three months after either having filled a first prescription for TRT or a PDE5i and compared this rate to the rate of non fatal MI in the preceding year. The authors concluded that the risk of MI is increased in older men and in younger men with pre-existing known heart disease who received testosterone prescriptions. Unfortunately, this study also has flaws in that it is impossible from the design to distinguish whether any observed difference was due to the underlying condition (T deficiency) or to its treatment (T prescription). Also the shorter the exposure time for a drug, the less likely it is responsible for an observed difference and though the authors had long term data (12 months) they did not report, raising a concern that the observed difference no longer persisted over time. Contrary to these three studies, new retrospective studies reveal no CVS dangers of TRT, and in fact suggest a possible protective mechanism. One trial suggests a 7-fold decrease in risk of MI. These studies would support multiple previous publications that suggest that men with normal T levels actually have longer life expectancies than hypogonadal men and that both low and high T levels have negative physiologic impact on male health. In summary, “expert views” from all walks of life (endocrinologists, epidemiologists, gerontologists, public health experts and urologists; lay press and regulatory agencies; pharmaceutical and film industry) is resulting in a cacophony of opinions creating much confusion and detriment to patients and physicians alike. A properly funded and implemented longitudinal study, similar to the Women’s Health Initiative, is required before we can address the true prostate and cardiovascular safety of TRT in the hypogonadal man. Until then, the application of this therapy should be personalized to the needs of the individual.
Zhao, Rui; Li, Yan; Dai, Wen
2016-01-01
Epidemiological studies have shown a high prevalence of low serum testosterone levels in men with cardiovascular disease. Moreover, the tyrosine kinase receptor Axl, the ligand of which is growth arrest-specific protein 6 (GAS6), is expressed in the vasculature, and serum GAS6 levels are associated with endothelial dysfunction and cardiovascular events. Testosterone regulates GAS6 gene transcription directly, which inhibits calcification of vascular smooth muscle cells and provides a mechanistic insight into the cardioprotective action of androgens. This study was designed to determine the correlation between serum GAS6 and testosterone levels in male patients with coronary heart disease (CHD). We recruited 225 patients with CHD and 102 apparently healthy controls. Serum concentrations of GAS6 and soluble Axl were quantified by an enzyme-linked immunosorbent assay. Levels of high-sensitivity C-reactive protein, testosterone, estradiol, and other routine biochemical markers were also measured. Testosterone decreased from 432.69 ± 14.40 to 300.76 ± 6.23 ng dl-1 (P < 0.001) and GAS6 decreased from 16.20 ± 0.31 to 12.51 ± 0.19 ng ml-1 (P < 0.001) in patients with CHD, compared with control subjects. Multiple linear regression analysis showed that serum testosterone and GAS6 levels were positively associated in male patients with CHD. Alterations in GAS6 levels may influence the development of CHD. Downregulation of GAS6/Axl signaling in the presence of low sex hormone levels during disease progression is a potential mechanism by which GAS6 affects CHD. This study provides novel results regarding the influence of sex hormones on serum GAS6 levels in patients with CHD.
Ose, Jennifer; Poole, Elizabeth M.; Schock, Helena; Lehtinen, Matti; Arslan, Alan A.; Zeleniuch-Jacquotte, Anne; Visvanathan, Kala; Helzlsouer, Kathy; Buring, Julie E.; Lee, I-Min; Tjønneland, Anne; Dossus, Laure; Trichopoulou, Antonia; Masala, Giovanna; Onland-Moret, N. Charlotte; Weiderpass, Elisabete; Duell, Eric J.; Idahl, Annika; Travis, Ruth C.; Rinaldi, Sabina; Merritt, Melissa A.; Trabert, Britton; Wentzensen, Nicolas; Tworoger, Shelley S.; Kaaks, Rudolf; Fortner, Renée T.
2017-01-01
Invasive epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy. The etiology of EOC remains elusive; however, experimental and epidemiologic data suggest a role for hormone-related exposures in ovarian carcinogenesis and risk factor differences by histologic phenotypes and developmental pathways. Research on pre-diagnosis androgen concentrations and EOC risk has yielded inconclusive results, and analyses incorporating EOC subtypes are sparse. We conducted a pooled analysis of 7 nested case-control studies in the Ovarian Cancer Cohort Consortium to investigate the association between pre-diagnosis circulating androgens (testosterone, free testosterone, androstenedione, dehydroepiandrosterone sulfate (DHEAS)), sex hormone binding globulin (SHBG), and EOC risk by tumor characteristics (i.e. histology, grade, and stage). The final study population included 1,331 EOC cases and 3,017 matched controls. Multivariable conditional logistic regression was used to assess risk associations in pooled individual data. Testosterone was positively associated with EOC risk (all subtypes combined, Odds Ratio (OR)log2=1.12 [95% Confidence Interval (CI) 1.02–1.24]); other endogenous androgens and SHBG were not associated with overall risk. Higher concentrations of testosterone and androstenedione associated with an increased risk in endometrioid and mucinous tumors (e.g., testosterone, endometrioid tumors, ORlog2=1.40 [1.03–1.91]), but not serous or clear cell. An inverse association was observed between androstenedione and high grade serous tumors (ORlog2=0.76 [0.60–0.96]). Our analyses provide further evidence for a role of hormone-related pathways in EOC risk, with differences in associations between androgens and histologic subtypes of EOC. PMID:28381542
Behavioral evidence for sex steroids hypersensitivity in castrated male canaries.
Shevchouk, Olesya; Ghorbanpoor, Samar; Smith, Ed; Liere, Philippe; Schumacher, Michael; Ball, Gregory F; Cornil, Charlotte A; Balthazart, Jacques
2018-06-14
In seasonally breeding songbirds such as canaries, singing behavior is predominantly under the control of testosterone and its metabolites. Short daylenths in the fall that break photorefractoriness are followed by increasing daylengths in spring that activate singing via both photoperiodic and hormonal mechanisms. However, we observed in a group of castrated male Fife fancy canaries maintained for a long duration under a short day photoperiod a large proportion of subjects that sang at high rates. This singing rate was not correlated with variation in the low circulating concentrations of testosterone. Treatment of these actively singing castrated male canaries with a combination of an aromatase inhibitor (ATD) and an androgen receptor blocker (flutamide) only marginally decreased this singing activity as compared to control untreated birds and did not affect various measures of song quality. The volumes of HVC and of the medial preoptic nucleus (POM) were also unaffected by these treatments but were relatively large and similar to volumes in testosterone-treated males. In contrast, peripheral androgen-sensitive structures such as the cloacal protuberance and syrinx mass were small, similar to what is observed in castrates. Together these data suggest that after a long-term steroid deprivation singing behavior can be activated by very low concentrations of testosterone. Singing normally depends on the activation by testosterone and its metabolites of multiple downstream neurochemical systems such as catecholamines, nonapeptides or opioids. These transmitter systems might become hypersensitive to steroid action after long term castration as they probably are at the end of winter during the annual cycle in seasonally breeding temperate zone species. Copyright © 2017. Published by Elsevier Inc.
Schradin, Carsten
2008-04-01
Animals have to adjust their physiology to seasonal changes, in response to variation in food availability, social tactics and reproduction. I compared basal corticosterone and testosterone levels in free ranging striped mouse from a desert habitat, comparing between the sexes, breeding and philopatric non-breeding individuals, and between the breeding and the non-breeding season. I expected differences between breeders and non-breeders and between seasons with high and low food availability. Basal serum corticosterone was measured from 132 different individuals and serum testosterone from 176 different individuals of free living striped mice. Corticosterone and testosterone levels were independent of age, body weight and not influenced by carrying a transmitter. The levels of corticosterone and testosterone declined by approximately 50% from the breeding to the non-breeding season in breeding females as well as non-breeding males and females. In contrast, breeding males showed much lower corticosterone levels during the breeding season than all other classes, and were the only class that showed an increase of corticosterone from the breeding to the non-breeding season. As a result, breeding males had similar corticosterone levels as other social classes during the non-breeding season. During the breeding season, breeding males had much higher testosterone levels than other classes, which decreased significantly from the breeding to the non-breeding season. My results support the prediction that corticosterone decreases during periods of low food abundance. Variation in the pattern of hormonal secretion in striped mice might assist them to cope with seasonal changes in energy demand in a desert habitat.
Resnick, Susan M; Matsumoto, Alvin M; Stephens-Shields, Alisa J; Ellenberg, Susan S; Gill, Thomas M; Shumaker, Sally A; Pleasants, Debbie D; Barrett-Connor, Elizabeth; Bhasin, Shalender; Cauley, Jane A; Cella, David; Crandall, Jill P; Cunningham, Glenn R; Ensrud, Kristine E; Farrar, John T; Lewis, Cora E; Molitch, Mark E; Pahor, Marco; Swerdloff, Ronald S; Cifelli, Denise; Anton, Stephen; Basaria, Shehzad; Diem, Susan J; Wang, Christina; Hou, Xiaoling; Snyder, Peter J
2017-02-21
Most cognitive functions decline with age. Prior studies suggest that testosterone treatment may improve these functions. To determine if testosterone treatment compared with placebo is associated with improved verbal memory and other cognitive functions in older men with low testosterone and age-associated memory impairment (AAMI). The Testosterone Trials (TTrials) were 7 trials to assess the efficacy of testosterone treatment in older men with low testosterone levels. The Cognitive Function Trial evaluated cognitive function in all TTrials participants. In 12 US academic medical centers, 788 men who were 65 years or older with a serum testosterone level less than 275 ng/mL and impaired sexual function, physical function, or vitality were allocated to testosterone treatment (n = 394) or placebo (n = 394). A subgroup of 493 men met criteria for AAMI based on baseline subjective memory complaints and objective memory performance. Enrollment in the TTrials began June 24, 2010; the final participant completed treatment and assessment in June 2014. Testosterone gel (adjusted to maintain the testosterone level within the normal range for young men) or placebo gel for 1 year. The primary outcome was the mean change from baseline to 6 months and 12 months for delayed paragraph recall (score range, 0 to 50) among men with AAMI. Secondary outcomes were mean changes in visual memory (Benton Visual Retention Test; score range, 0 to -26), executive function (Trail-Making Test B minus A; range, -290 to 290), and spatial ability (Card Rotation Test; score range, -80 to 80) among men with AAMI. Tests were administered at baseline, 6 months, and 12 months. Among the 493 men with AAMI (mean age, 72.3 years [SD, 5.8]; mean baseline testosterone, 234 ng/dL [SD, 65.1]), 247 were assigned to receive testosterone and 246 to receive placebo. Of these groups, 247 men in the testosterone group and 245 men in the placebo completed the memory study. There was no significant mean change from baseline to 6 and 12 months in delayed paragraph recall score among men with AAMI in the testosterone and placebo groups (adjusted estimated difference, -0.07 [95% CI, -0.92 to 0.79]; P = .88). Mean scores for delayed paragraph recall were 14.0 at baseline, 16.0 at 6 months, and 16.2 at 12 months in the testosterone group and 14.4 at baseline, 16.0 at 6 months, and 16.5 at 12 months in the placebo group. Testosterone was also not associated with significant differences in visual memory (-0.28 [95% CI, -0.76 to 0.19]; P = .24), executive function (-5.51 [95% CI, -12.91 to 1.88]; P = .14), or spatial ability (-0.12 [95% CI, -1.89 to 1.65]; P = .89). Among older men with low testosterone and age-associated memory impairment, treatment with testosterone for 1 year compared with placebo was not associated with improved memory or other cognitive functions. clinicaltrials.gov Identifier: NCT00799617.
Clague, J E; Wu, F C; Horan, M A
1999-08-01
Muscle wasting in older men may be related to androgen deficiency. We have assessed the effect of testosterone replacement therapy on muscle function in the upper and lower limbs of older (age > 60 years) men with blood testosterone levels < 14 nmol/L. Subjects (n = 7 per group) received testosterone enanthate 200 mg i.m. or placebo every 2 weeks in a double blind study over a 12-week period and underwent muscle testing every 4 weeks. A significant increase in blood levels of testosterone and a reduction in levels of sex hormone binding globulin occurred in the treatment group. Total body mass, haemoglobin and packed cell volume also increased significantly (p < 0.05). No improvements in handgrip strength, isometric strength of knee flexors and extensors or leg extensor power were seen in either group. Wide variability in all measures of muscle function were observed in these elderly men suggesting that very large study groups would be required to determine potential treatment benefits on muscle function.
Monaco, Davide; Fatnassi, Meriem; Padalino, Barbara; Aubé, Lydiane; Khorchani, Touhami; Hammadi, Mohamed; Lacalandra, Giovanni Michele
2015-10-01
GnRH treatment has been suggested to increase testosterone levels temporarily and to stimulate libido in stallions, but its use has not fully ascertained in dromedary camels. The aim of this work was to study the effects of administering 100 μg of GnRH on testosterone profile, libido and semen parameters in dromedary camels. The same bulls were used as self-controls and experimental group. Blood samples were collected every 20 min (T0-T12) for 4h, and semen collections were performed over a 2-hour period after T12. GnRH was administered immediately after T0. In GnRH-treated bulls, testosterone levels showed an upward trend, peaking after 140 min, and then slowly decreasing. GnRH administration also led to a decrease in mating time and an increase in spermatozoa concentration. Overall, it seems that administration of 100 μg GnRH might increase testosterone levels temporarily and enhance camel reproduction performance. Copyright © 2015 Elsevier Ltd. All rights reserved.
Late-Onset Hypogonadism and Testosterone Replacement in Older Men.
Bhattacharya, Rajib K; Bhattacharya, Shelley B
2015-11-01
Late-onset hypogonadism is an underdiagnosed and easily treated condition defined by low serum testosterone levels in men older than 65 years. When treated, a significant improvement in quality of life may be reached in this rapidly rising sector of the population. During the evaluation, laboratory tests and a full medication review should be performed to exclude other illnesses or adverse effects from medications. The major goal of treatment in this population is treating the symptoms related to hypogonadism. There has not been clear evidence supporting universally giving older men with low serum testosterone levels and hypogonadal symptoms testosterone replacement therapy. Copyright © 2015 Elsevier Inc. All rights reserved.
Estradiol and inflammatory markers in older men.
Maggio, Marcello; Ceda, Gian Paolo; Lauretani, Fulvio; Bandinelli, Stefania; Metter, E Jeffrey; Artoni, Andrea; Gatti, Elisa; Ruggiero, Carmelinda; Guralnik, Jack M; Valenti, Giorgio; Ling, Shari M; Basaria, Shehzad; Ferrucci, Luigi
2009-02-01
Aging is characterized by a mild proinflammatory state. In older men, low testosterone levels have been associated with increasing levels of proinflammatory cytokines. It is still unclear whether estradiol (E2), which generally has biological activities complementary to testosterone, affects inflammation. We analyzed data obtained from 399 men aged 65-95 yr enrolled in the Invecchiare in Chianti study with complete data on body mass index (BMI), serum E2, testosterone, IL-6, soluble IL-6 receptor, TNF-alpha, IL-1 receptor antagonist, and C-reactive protein. The relationship between E2 and inflammatory markers was examined using multivariate linear models adjusted for age, BMI, smoking, physical activity, chronic disease, and total testosterone. In age-adjusted analysis, log (E2) was positively associated with log (IL-6) (r = 0.19; P = 0.047), and the relationship was statistically significant (P = 0.032) after adjustments for age, BMI, smoking, physical activity, chronic disease, and serum testosterone levels. Log (E2) was not significantly associated with log (C-reactive protein), log (soluble IL-6 receptor), or log (TNF-alpha) in both age-adjusted and fully adjusted analyses. In older men, E2 is weakly positively associated with IL-6, independent of testosterone and other confounders including BMI.
Kulin, H E; Finkelstein, J W; D'Arcangelo, M R; Susman, E J; Chinchilli, V; Kunselman, S; Schwab, J; Demers, L; Lookingbill, G
1997-01-01
In a group of 22 boys with constitutional delay in growth and/or adolescence, intermittent testosterone enanthate treatment was employed in a randomized clinical trial at multiple doses ranging from 25-100 mg every two weeks for three month periods extending over 15-21 months. Twelve of the patients displayed a prompt increase in endogenous testosterone levels during the study period, reaching levels in the adult male range (> 250 ng/dl). The remaining 10 boys showed sluggish changes in endogenous testosterone during the investigation, ranging from 35-177 ng/dl. The bone ages and testicular sizes of the two groups at study initiation did not differ though urine LH was significantly less at study entry in the slowly maturing group. The data reveal a great diversity in the pace and pattern of endogenous testosterone changes in the study population. The results also suggest that exogenous sex steroid treatment of such patients does not speed up the central nervous system processes controlling the onset and progression of puberty. Boys with delayed puberty should be followed until endogenous testosterone levels reach the adult male range in order to rule out mild gonadotropin deficits.
Testosterone and Occupational Achievement.
ERIC Educational Resources Information Center
Dabbs, James M., Jr.
1992-01-01
Archival data on 4,462 military veterans linked higher levels of serum testosterone to lower-status occupations. A structural equation model was supported in which higher testosterone, mediated through lower intellectual ability, greater antisocial behavior, and lower education, leads away from white-collar occupations. Contains 49 references.…
Testosterone regulates erectile function and Vcsa1 expression in the corpora of rats.
Chua, Rowena G; Calenda, Giulia; Zhang, Xinhua; Siragusa, Joseph; Tong, Yuehong; Tar, Moses; Aydin, Memduh; DiSanto, Michael E; Melman, Arnold; Davies, Kelvin P
2009-05-06
Vcsa1 plays an important role in the erectile physiology of the rat. We conducted experiments to determine if erectile function, testosterone levels and Vcsa1 expression were correlated. In orchiectomized rats, total testosterone in blood fell from an average of 4 ng/ml to <0.04 ng/ml. Erectile function was significantly lower compared to controls and Vcsa1 expression was significantly (>6-fold) decreased. Injection of orchiectomized animals with testosterone (2 mg in 100ml sesame oil every 4 days for 2 weeks) restored average levels of testosterone to 2 ng/ml, increased erectile function and significantly increased Vcsa1 expression. In isolated corporal cells there was testosterone dependent Vcsa1 expression. However, intracorporal injection of orchiectomized animals with a plasmid expressing Vcsa1 or its gene product Sialorphin (previously demonstrated to improve erectile function in old animals) gave no significant improvement in erectile function. Also, the ability of Sialorphin to reduce tension in corporal smooth muscle strips isolated from orchiectomized animals was impaired compared to controls.
Salivary testosterone and cortisol are jointly related to pro-environmental behavior in men.
Sollberger, Silja; Bernauer, Thomas; Ehlert, Ulrike
2016-10-01
Recently, cortisol has been suggested to moderate the positive relationship between testosterone and antisocial behavior. More precisely, high testosterone levels have been found to be related to aggressive or dominant behavior especially when cortisol levels were low. In the present study, we aimed to extend these findings to pro-environmental behavior as an indicator of prosocial behavior. In a first step, 147 male participants provided information on their everyday pro-environmental behavior by completing an online questionnaire on various energy-saving behaviors. In a second step, subjects provided two saliva samples for the assessment of testosterone and cortisol on two subsequent mornings after awakening. We found that testosterone was negatively related to pro-environmental behavior, but only in men with low cortisol. In conclusion, our findings provide first evidence for the joint association of testosterone and cortisol with everyday pro-environmental behavior. These results further reinforce the importance of considering interdependent hormone systems simultaneously rather than focusing on a single hormone.
Testosterone administration decreases generosity in the ultimatum game.
Zak, Paul J; Kurzban, Robert; Ahmadi, Sheila; Swerdloff, Ronald S; Park, Jang; Efremidze, Levan; Redwine, Karen; Morgan, Karla; Matzner, William
2009-12-16
How do human beings decide when to be selfish or selfless? In this study, we gave testosterone to 25 men to establish its impact on prosocial behaviors in a double-blind within-subjects design. We also confirmed participants' testosterone levels before and after treatment through blood draws. Using the Ultimatum Game from behavioral economics, we find that men with artificially raised T, compared to themselves on placebo, were 27% less generous towards strangers with money they controlled (95% CI placebo: (1.70, 2.72); 95% CI T: (.98, 2.30)). This effect scales with a man's level of total-, free-, and dihydro-testosterone (DHT). Men in the lowest decile of DHT were 560% more generous than men in the highest decile of DHT. We also found that men with elevated testosterone were more likely to use their own money punish those who were ungenerous toward them. Our results continue to hold after controlling for altruism. We conclude that elevated testosterone causes men to behave antisocially.
Testosterone Administration Decreases Generosity in the Ultimatum Game
Zak, Paul J.; Kurzban, Robert; Ahmadi, Sheila; Swerdloff, Ronald S.; Park, Jang; Efremidze, Levan; Redwine, Karen; Morgan, Karla; Matzner, William
2009-01-01
How do human beings decide when to be selfish or selfless? In this study, we gave testosterone to 25 men to establish its impact on prosocial behaviors in a double-blind within-subjects design. We also confirmed participants' testosterone levels before and after treatment through blood draws. Using the Ultimatum Game from behavioral economics, we find that men with artificially raised T, compared to themselves on placebo, were 27% less generous towards strangers with money they controlled (95% CI placebo: (1.70, 2.72); 95% CI T: (.98, 2.30)). This effect scales with a man's level of total-, free-, and dihydro-testosterone (DHT). Men in the lowest decile of DHT were 560% more generous than men in the highest decile of DHT. We also found that men with elevated testosterone were more likely to use their own money punish those who were ungenerous toward them. Our results continue to hold after controlling for altruism. We conclude that elevated testosterone causes men to behave antisocially. PMID:20016825
2016-05-01
multiple pathways, despite castrate levels of testosterone . One such adaptive mechanism is the “intracrine” production of androgens in the primary...despite castrate levels of testosterone . One such adaptive mechanism is the “intracrine” production of androgens in the primary tumor and/or at... testosterone . Thus, just as the skeleton regulates fertility in an endocrine fashion, and it may also promote bone metastasis via an “intracrine” mechanism
Bhasin, Shalender; Cunningham, Glenn R; Hayes, Frances J; Matsumoto, Alvin M; Snyder, Peter J; Swerdloff, Ronald S; Montori, Victor M
2006-06-01
The objective was to provide guidelines for the evaluation and treatment of androgen deficiency syndromes in adult men. The Task Force was composed of a chair, selected by the Clinical Guidelines Subcommittee of The Endocrine Society, five additional experts, a methodologist, and a professional writer. The Task Force received no corporate funding or remuneration. The Task Force used systematic reviews of available evidence to inform its key recommendations. The Task Force used consistent language and graphical descriptions of both the strength of recommendation and the quality of evidence, using the recommendations of the Grading of Recommendations, Assessment, Development, and Evaluation group. Consensus was guided by systematic reviews of evidence and discussions during three group meetings, several conference calls, and e-mail communications. The drafts prepared by the panelists with the help of a professional writer were reviewed successively by The Endocrine Society's Clinical Guidelines Subcommittee, Clinical Affairs Committee, and Council. The version approved by the Council was placed on The Endocrine Society's web site for comments by members. At each stage of review, the Task Force received written comments and incorporated needed changes. We recommend making a diagnosis of androgen deficiency only in men with consistent symptoms and signs and unequivocally low serum testosterone levels. We suggest the measurement of morning total testosterone level by a reliable assay as the initial diagnostic test. We recommend confirmation of the diagnosis by repeating the measurement of morning total testosterone and in some patients by measurement of free or bioavailable testosterone level, using accurate assays. We recommend testosterone therapy for symptomatic men with androgen deficiency, who have low testosterone levels, to induce and maintain secondary sex characteristics and to improve their sexual function, sense of well-being, muscle mass and strength, and bone mineral density. We recommend against starting testosterone therapy in patients with breast or prostate cancer, a palpable prostate nodule or induration or prostate-specific antigen greater than 3 ng/ml without further urological evaluation, erythrocytosis (hematocrit > 50%), hyperviscosity, untreated obstructive sleep apnea, severe lower urinary tract symptoms with International Prostate Symptom Score (IPSS) greater than 19, or class III or IV heart failure. When testosterone therapy is instituted, we suggest aiming at achieving testosterone levels during treatment in the mid-normal range with any of the approved formulations, chosen on the basis of the patient's preference, consideration of pharmacokinetics, treatment burden, and cost. Men receiving testosterone therapy should be monitored using a standardized plan.
Wong, Jenny K Y; Leung, David K K; Curl, Peter; Schiff, Peter J; Lam, Kenneth K H; Wan, Terence S M
2017-09-01
The detection of boldenone, nandrolone, 5(10)-estrene-3β,17α-diol, and 4-estrene-3,17-dione in a urine sample collected from a gelding having been treated with testosterone (500 mg 'Testosterone Suspension 100', single dose, injected intramuscularly) in 2009 led the authors' laboratory to suspect that these 'testicular' steroids could be minor metabolites of testosterone in geldings. Administration trials on six castrated horses with Testosterone Suspension 100 confirmed that low levels of boldenone, nandrolone, 5(10)-estrene-3β,17α-diol, and 4-estrene-3,17-dione could indeed be detected and confirmed in the early post-administration urine samples from all six geldings. Although boldenone has been reported to be present in urine after testosterone administration, there has been no direct evidence reported that boldenone, nandrolone, 5(10)-estrene-3β,17α-diol, and 4-estrene-3,17-dione are metabolites of testosterone in geldings. Subsequent in vitro experiments involving the incubation of testosterone with horse liver microsomes, liver, adipose and muscle tissues, and adrenal cortex homogenates failed to provide evidence that these four substances are minor metabolites of testosterone. An administration trial using 'Testosterone Suspension 100' supplemented with 13 C-labelled testosterone (500 mg, 1:1 ratio, injected intramuscularly) was performed. The similarities of the excretion curves of 12 C-testosterone and 13 C-testosterone in urine suggest that there was minimal kinetic isotope effect. 13 C-Labelled boldenone, nandrolone and 4-estrene-3,17-dione were detected but not 5(10)-estrene-3β,17α-diol and its 13 C-counterpart. This is the first unequivocal evidence of boldenone, nandrolone and 4-estrene-3,17-dione being metabolites of testosterone in geldings. In view of these results, caution should be exercised when interpreting findings of boldenone, nandrolone and/or 4-estrene-3,17-dione together with a relatively high level of testosterone in gelding urine. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Testosterone in human studies: Modest associations between plasma and salivary measurements.
de Wit, A E; Bosker, F J; Giltay, E J; de Kloet, C S; Roelofs, K; van Pelt, J; Penninx, B W J H; Schoevers, R A
2018-02-01
Testosterone is involved in many processes like aggression and mood disorders. As it may easily diffuse from blood into saliva, salivary testosterone is thought to reflect plasma free testosterone level. If so, it would provide a welcome noninvasive and less stressful alternative to blood sampling. Past research did not reveal consensus regarding the strength of the association, but sample sizes were small. This study aimed to analyse the association in a large cohort. In total, 2,048 participants (age range 18-65 years; 696 males and 1,352 females) were included and saliva (using cotton Salivettes) and plasma were collected for testosterone measurements. Levels were determined by enzyme-linked immunosorbent assay and radioimmunoassay respectively. Free testosterone was calculated by the Vermeulen algorithm. Associations were determined using linear regression analyses. Plasma total and free testosterone showed a significant association with salivary testosterone in men (adjusted β = .09, p = .01; and β = .15, p < .001, respectively) and in women (adjusted β = .08, p = .004; and crude β = .09, p = .002 respectively). The modest associations indicate that there are many influencing factors of both technical and biological origin. © 2017 Blackwell Verlag GmbH.
LeBrasseur, Nathan K.; Lajevardi, Newsha; Miciek, Renee; Mazer, Norman; Storer, Thomas W.; Bhasin, Shalender
2010-01-01
The TOM study is the first, single-site, placebo-controlled, randomized clinical trial designed to comprehensively determine the effects of testosterone administration on muscle strength and physical function in older men with mobility limitations. A total of 252 community dwelling individuals aged 65 and older with low testosterone levels and self-reported limitations in mobility and short physical performance battery (SPPB) score between 4 and 9 will be randomized to receive either placebo or testosterone therapy for 6 months. The primary objective is to determine whether testosterone therapy improves maximal voluntary muscle strength as quantified by the one repetition maximum. Secondary outcomes will include measures of physical function (walking, stair climbing and a lifting and lowering task), habitual physical activity and self-reported disability. The effects of testosterone on affect, fatigue and sense of well being will also be assessed. Unique aspects of the TOM Trial include selection of men with self-reported as well as objectively demonstrable functional limitations, community-based screening and recruitment, adjustment of testosterone dose to ensure serum testosterone levels in the target range while maintaining blinding, and inclusion of a range of self-reported and performance-based physical function measures as outcomes. Clinicaltrials.gov identifier: NCT00240981. PMID:18996225
LeBrasseur, Nathan K; Lajevardi, Newsha; Miciek, Renee; Mazer, Norman; Storer, Thomas W; Bhasin, Shalender
2009-03-01
The TOM study is the first, single-site, placebo-controlled, randomized clinical trial designed to comprehensively determine the effects of testosterone administration on muscle strength and physical function in older men with mobility limitations. A total of 252 community dwelling individuals aged 65 and older with low testosterone levels and self-reported limitations in mobility and short physical performance battery (SPPB) scores between 4 and 9 will be randomized to receive either placebo or testosterone therapy for 6 months. The primary objective is to determine whether testosterone therapy improves maximal voluntary muscle strength as quantified by the one repetition maximum. Secondary outcomes will include measures of physical function (walking, stair climbing and a lifting and lowering task), habitual physical activity and self-reported disability. The effects of testosterone on affect, fatigue and sense of well being will also be assessed. Unique aspects of the TOM Trial include selection of men with self-reported as well as objectively demonstrable functional limitations, community-based screening and recruitment, adjustment of testosterone dose to ensure serum testosterone levels in the target range while maintaining blinding, and inclusion of a range of self-reported and performance-based physical function measures as outcomes. Clinicaltrials.gov identifier: NCT00240981.
Ho, Chen-Hsun; Yu, Hong-Jeng; Wang, Chih-Yuan; Jaw, Fu-Shan; Hsieh, Ju-Ton; Liao, Wan-Chung; Pu, Yeong-Shiau; Liu, Shih-Ping
2013-01-01
Objective The association between type 2 diabetes and low testosterone has been well recognized. However, testosterone levels in men with prediabetes have been rarely reported. We aimed to investigate whether prediabetes was associated with an increased risk of testosterone deficiency. Methods This study included 1,306 men whose sex hormones was measured during a medical examination. Serum total testosterone and sex hormone-binding globulin were measured; free and bioavailable testosterone concentrations were calculated by Vermeulen’s formula. Prediabetes was defined by impaired fasting glucose (IFG), impaired postprandial glucose (IPG), or glycated hemoglobin (HbA1c) 5.7%-6.4%. Logistic regression was performed to obtain the odds ratios (OR) for subnormal total testosterone (<300 ng/dL) or free testosterone (<6 ng/dL) in prediabetic and diabetic men compared with normoglycemic individuals, while adjusting for age, BMI, waist circumference, and metabolic syndrome (MetS). Results Normoglycemia, prediabetes, and diabetes were diagnosed in 577 (44.2%), 543 (41.6%), and 186 (14.2%) men, respectively. Prediabetes was associated with an increased risk of subnormal total testosterone compared to normoglycemic individuals (age-adjusted OR=1.87; 95%CI=1.38-2.54). The risk remained significant in all multivariate analyses. After adjusting for MetS, the OR in prediabetic men equals that of diabetic patients (1.49 versus 1.50). IFG, IPG, and HbA1c 5.7%-6.4% were all associated with an increased risk of testosterone deficiency, with different levels of significance in multivariate analyses. However, neither prediabetes nor diabetes was associated with subnormal free testosterone in multivariate analyses. Conclusions Prediabetes is associated with an increased risk of testosterone deficiency, independent of obesity and MetS. After adjusting for MetS, the risk equals that of diabetes. Our data suggest that testosterone should be measured routinely in men with prediabetes. PMID:24069277
Effects of Tribulus terrestris on endocrine sensitive organs in male and female Wistar rats.
Martino-Andrade, Anderson J; Morais, Rosana N; Spercoski, Katherinne M; Rossi, Stefani C; Vechi, Marina F; Golin, Munisa; Lombardi, Natália F; Greca, Cláudio S; Dalsenter, Paulo R
2010-01-08
Investigate the possible effects of Tribulus terrestris (TT) on endocrine sensitive organs in intact and castrated male rats as well as in a post-menopausal rat model using ovariectomized females. Three different dose levels of TT (11, 42 and 110 mg/kg/day) were administered to castrated males for 7 days and to intact males and castrated females for 28 days. In addition to TT treatment, all experiments also included a group of rats treated with dehydroepiandrosterone (DHEA). In experiments using castrated males and females we also used testosterone and 17 alpha-ethynylestradiol, respectively, as positive controls for androgenicity and estrogenicity. Neither DHEA nor TT was able to stimulate androgen sensitive tissues like the prostate and seminal vesicle in both intact and castrated male rats. In addition, administration of TT to intact male rats for 28 days did not change serum testosterone levels as well as did not produce any quantitative change in the fecal excretion of androgenic metabolites. However, a slight increase in the number of homogenization-resistant spermatids was observed in rats treated with 11 mg/kg/day of TT extract. In ovariectomized females, TT did not produce any stimulatory effects in uterine and vaginal epithelia. Tribulus terrestris was not able to stimulate endocrine sensitive tissues such as the prostate, seminal vesicle, uterus and vagina in Wistar rats, indicating lack of androgenic and estrogenic activity in vivo. We also showed a positive effect of TT administration on rat sperm production, associated with unchanged levels of circulating androgens. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.
Early ovarian follicular development in prepubertal Wistar rats acutely exposed to androgens.
Paixão, L; Velez, L M; Santos, B R; Tusset, C; Lecke, S B; Motta, A B; Spritzer, P M
2016-08-01
Androgens may directly modulate early ovarian follicular development in preantral stages and androgen excess before puberty may disrupt this physiological process. Therefore, the aim of this study was to investigate the dynamics of follicular morphology and circulating androgen and estradiol levels in prepubertal Wistar rats acutely exposed to androgens. Prepubertal female Wistar rats were distributed into three groups: control, equine chorionic gonadotropin (eCG) intervention and eCG plus dehydroepiandrosterone (DHEA) intervention (eCG+DHEA). Serum DHEA, testosterone and estradiol levels were determined, and ovarian morphology and morphometry were assessed. The eCG+DHEA group presented increased serum estradiol and testosterone levels as compared with the control group (P<0.01), and higher serum DHEA concentration v. the eCG-only and control groups (P<0.01). In addition, the eCG+DHEA group had a higher number of, and larger-sized, primary and secondary follicles as compared with the control group (P<0.05). The eCG group presented intermediate values for number and size of primary and secondary follicles, without significant differences as compared with the other two groups. The number of antral follicles was higher in the eCG+DHEA and eCG groups v. controls (P<0.05). The number of primordial, atretic and cystic follicles were similar in all groups. In conclusion, the present experimental model using an acute eCG+DHEA intervention was useful to investigate events involved in initial follicular development under hyperandrogenic conditions, and could provide a reliable tool to study defective follicular development with possible deleterious reproductive consequences later in life.
Doperalski, Nicholas J.; Martyniuk, Christopher J.; Prucha, Melinda S.; Kroll, Kevin J.; Denslow, Nancy D.; Barber, David S.
2011-01-01
Cholesterol transport across the mitochondrial membrane is rate-limiting for steroidogenesis in vertebrates. Previous studies in fish have characterized expression of the steroidogenic acute regulatory protein, however the function and regulation of other genes and proteins involved in piscine cholesterol transport have not been evaluated. In the current study, mRNA sequences of the 18 kDa translocator protein (tspo; formerly peripheral benzodiazepine receptor), voltage-dependent anion channel (vdac), and diazepam binding inhibitor (dbi; also acyl-CoA binding protein) were cloned from largemouth bass. Gonadal expression was examined across reproductive stages to determine if expression is correlated with changes in steroid levels and with indicators of reproductive maturation. In testis, transcript abundance of tspo and dbi increased with reproductive maturation (6- and 23-fold maximal increase, respectively) and expression of tspo and dbi was positively correlated with reproductive stage, gonadosomatic index (GSI), and circulating levels of testosterone. Testis vdac expression was positively correlated with reproductive stage and GSI. In females, gonadal tspo and vdac expression was negatively correlated with GSI and levels of plasma testosterone and 17β-estradiol. Ovarian dbi expression was not correlated with indicators of reproductive maturation. These studies represent the first investigation of the steroidogenic role of tspo, vdac, and dbi in fish. Findings suggest that cholesterol transport in largemouth bass testis, but not ovary, may be transcriptionally-regulated, however further investigation will be necessary to fully elucidate the role of these genes in largemouth bass steroidogenesis. PMID:21600210
Sex steroid hormones in relation to Barrett's esophagus: an analysis of the FINBAR Study.
Cook, M B; Wood, S; Hyland, P L; Caron, P; Drahos, J; Falk, R T; Pfeiffer, R M; Dawsey, S M; Abnet, C C; Taylor, P R; Guillemette, C; Murray, L J; Anderson, L A
2017-03-01
Previously, we observed strong positive associations between circulating concentrations of free testosterone and free dihydrotestosterone (DHT) in relation to Barrett's esophagus in a US male military population. To replicate these findings, we conducted a second study of sex steroid hormones and Barrett's esophagus in the Factors Influencing the Barrett/Adenocarcinoma Relationship (FINBAR) Study based in Northern Ireland and Ireland. We used mass spectrometry to quantitate EDTA plasma concentrations of nine sex steroid hormones and ELISA to quantitate sex hormone-binding globulin in 177 male Barrett's esophagus cases and 185 male general population controls within the FINBAR Study. Free testosterone, free DHT, and free estradiol were estimated using standard formulas. Multivariable logistic regression estimated odds ratios (OR) and 95% confidence intervals (95%CI) of associations between exposures and Barrett's esophagus. While plasma hormone and sex hormone-binding globulin concentrations were not associated with all cases of Barrett's esophagus, we did observe positive associations with estrogens in younger men (e.g. estrone + estradiol OR continuous per ½ IQR = 2.92, 95%CI:1.08, 7.89), and free androgens in men with higher waist-to-hip ratios (e.g. free testosterone OR continuous per ½ IQR = 2.71, 95%CI:1.06, 6.92). Stratification by body mass index, antireflux medications, and geographic location did not materially affect the results. This study found evidence for associations between circulating sex steroid hormones and Barrett's esophagus in younger men and men with higher waist-to-hip ratios. Further studies are necessary to elucidate whether sex steroid hormones are consistently associated with esophageal adenocarcinogenesis. © 2017 American Society of Andrology and European Academy of Andrology.
Testosterone and aggressive behavior in man.
Batrinos, Menelaos L
2012-01-01
Atavistic residues of aggressive behavior prevailing in animal life, determined by testosterone, remain attenuated in man and suppressed through familial and social inhibitions. However, it still manifests itself in various intensities and forms from; thoughts, anger, verbal aggressiveness, competition, dominance behavior, to physical violence. Testosterone plays a significant role in the arousal of these behavioral manifestations in the brain centers involved in aggression and on the development of the muscular system that enables their realization. There is evidence that testosterone levels are higher in individuals with aggressive behavior, such as prisoners who have committed violent crimes. Several field studies have also shown that testosterone levels increase during the aggressive phases of sports games. In more sensitive laboratory paradigms, it has been observed that participant's testosterone rises in the winners of; competitions, dominance trials or in confrontations with factitious opponents. Aggressive behavior arises in the brain through interplay between subcortical structures in the amygdala and the hypothalamus in which emotions are born and the prefrontal cognitive centers where emotions are perceived and controlled. The action of testosterone on the brain begins in the embryonic stage. Earlier in development at the DNA level, the number of CAG repeats in the androgen receptor gene seems to play a role in the expression of aggressive behavior. Neuroimaging techniques in adult males have shown that testosterone activates the amygdala enhancing its emotional activity and its resistance to prefrontal restraining control. This effect is opposed by the action of cortisol which facilitates prefrontal area cognitive control on impulsive tendencies aroused in the subcortical structures. The degree of impulsivity is regulated by serotonin inhibiting receptors, and with the intervention of this neurotransmitter the major agents of the neuroendocrine influence on the brain process of aggression forms a triad. Testosterone activates the subcortical areas of the brain to produce aggression, while cortisol and serotonin act antagonistically with testosterone to reduce its effects.
Rodriguez-Tolrà, J; Torremadé, J; di Gregorio, S; Del Rio, L; Franco, E
2013-07-01
The decline in testosterone levels found in men with testosterone deficiency syndrome (TDS) is associated with a decrease in bone mineral density (BMD). To study the safety profile and efficacy of testosterone treatment on BMD in patients with TDS. In this 2-year prospective open-label study, patients were administered 50 mg of testosterone gel daily (adjustable after 3 months up to 75-100 mg or down to 25 mg) for 12 months, followed by treatment with 1000 mg of testosterone undecanoate every 2-3 months from months 12-24. Outcome measures were as follows: (i) Changes in clinical chemistry safety parameters and total testosterone, sex hormone binding globulin and calculated free testosterone (cFT) levels; (ii) Changes in Aging Males' Symptoms Scale (AMS) and International Prostate Symptom Score scores; and (iii) Changes in lumbar spine and hip BMD. A total of 50 men aged 50-65 years with TDS (AMS >26 and cFT <0.250 nmol/mL) took part in the study. There was no significant impact of testosterone on safety. Prostate-specific antigen and haematopoietic parameters increased significantly, although the changes were not clinically significant. Total and cFT increased significantly after 3 months (p < 0.001) and there were significant improvements after 3 months in AMS scores (p < 0.001). BMD improved significantly in L2-L4 (2.90 and 4.5%), total femur (0.74 and 3%) and trochanter (1.09 and 3.2%) at 12 and 24 months respectively. Testosterone treatment in men with TDS has a good safety profile, leads to significant improvement in lumbar spine and hip BMD, and improves symptoms, as assessed by the AMS questionnaire. © 2013 American Society of Andrology and European Academy of Andrology.
Mascaro, Jennifer S.; Hackett, Patrick D.; Rilling, James K.
2015-01-01
Despite the well-documented importance of paternal caregiving for positive child development, little is known about the neural changes that accompany the transition to fatherhood in humans, or about how changes in hormone levels affect paternal brain function. We compared fathers of children aged 1–2 with non-fathers in terms of hormone levels (oxytocin and testosterone), neural responses to child picture stimuli, and neural responses to visual sexual stimuli. Compared to non-fathers, fathers had significantly higher levels of plasma oxytocin and lower levels of plasma testosterone. In response to child picture stimuli, fathers showed stronger activation than non-fathers within regions important for face emotion processing (caudal middle frontal gyrus [MFG]), mentalizing (temporo-parietal junction [TPJ]) and reward processing (medial orbitofrontal cortex [mOFC]). On the other hand, non-fathers had significantly stronger neural responses to sexually provocative images in regions important for reward and approach-related motivation (dorsal caudate and nucleus accumbens). Testosterone levels were negatively correlated with responses to child stimuli in the MFG. Surprisingly, neither testosterone nor oxytocin levels predicted neural responses to sexual stimuli. Our results suggest that the decline in testosterone that accompanies the transition to fatherhood may be important for augmenting empathy toward children. PMID:24882167
Kim, Hye-Jung; Koo, Hyung Suk; Kim, Young-Sang; Kim, Moon Jong; Kim, Kwang-Min; Joo, Nam-Seok; Haam, Ji-Hee
2017-11-01
Testosterone and insulin-like growth factor-1 (IGF-1) are essential factors for the maintenance of bone health in men. However, the results for the association of testosterone and IGF-1 with bone parameters were not consistent in prior studies. We evaluated the relationship of testosterone, sex hormone-binding globulin (SHBG), and IGF-1 with bone mineral density (BMD) and bone turnover markers (BTMs) in Korean men. We enrolled 1227 men aged ≥50 years in this cross-sectional study. Serum levels of total testosterone (TT), SHBG, IGF-1, osteocalcin, and C-terminal cross-linking telopeptide of type I collagen (CTX) were measured. Free testosterone (FT) was calculated using Vermeulen's method. BMD was measured by dual-energy X-ray absorptiometry. TT level was not related to BMD or BTMs in the unadjusted model; however, after adjusting for SHBG and IGF-1, the association between TT and BTMs was significant (β = -0.139 for osteocalcin and β = -0.204 for CTX). SHBG levels were negatively associated with lumbar BMD, and positively associated with BTMs in all models. As SHBG level increased, the prevalence of osteopenia or osteoporosis defined by BMD significantly increased (OR of 1SD change, 1.24). IGF-1 levels were significantly related with BMD, but not with BTMs. Meanwhile, FT levels were positively associated with BMD and negatively associated with BTMs. In conclusion, SHBG levels were independently related with bone parameters and osteopenia in men aged ≥50 years. IGF-1 levels were positively associated with BMD, but not with BTMs. SHBG may play a role in regulating age-related bone loss in men after middle-age.
Positive association of personal distress with testosterone in opiate-addicted patients.
Stange, Katrin; Krüger, Mathias; Janke, Eva; Lichtinghagen, Ralf; Bleich, Stefan; Hillemacher, Thomas; Heberlein, Annemarie
2017-01-01
Clinical studies report that substance addictions are associated with sociocognitive impairments. Regarding opiate-addicted patients, the few existing studies point to deficits in empathic abilities. Previous research suggests that testosterone might be a relevant biomarker of these impairments. The authors aimed to investigate whether opiate-addicted patients show specific impairments in emotional (empathic concern, personal distress) and cognitive empathy compared to healthy controls. Furthermore, the authors aimed to assess possible associations of testosterone levels with impaired empathic abilities in the patients' group. In this cross-sectional study, 27 opiate-addicted, diacetylmorphine-maintained patients (21 males, age mean 41.67 years, standard deviation 8.814) and 31 healthy controls (23 males, age mean 40.77 years, standard deviation 8.401) matched in age, sex, and educational level were examined. Cognitive and emotional empathy were measured via the German version of the Interpersonal Reactivity Index and salivary testosterone levels were assessed. The authors found higher personal distress scores (p < 0.01, d = 0.817) and higher testosterone (p < 0.001, d = 1.093) in the patients' group compared to controls. Moreover, a positive correlation was found between testosterone and personal distress among the patients' group (r = 0.399, p < 0.05). Opiate-addicted patients show specific impairments in emotional empathy, namely higher personal distress, which has clinical implications regarding social cognition rehabilitation and relapse prevention. The current data point toward testosterone as a possible biomarker for these sociocognitive impairments and suggest that high personal distress and high testosterone during withdrawal are possible markers for severe opiate addiction.
A Low-Testosterone State Associated with Endometrioma Leads to the Apoptosis of Granulosa Cells
Ono, Yoshihiro J.; Tanabe, Akiko; Nakamura, Yoko; Yamamoto, Hikaru; Hayashi, Atsushi; Tanaka, Tomohito; Sasaki, Hiroshi; Hayashi, Masami; Terai, Yoshito; Ohmichi, Masahide
2014-01-01
Although endometriosis is suspected to be a cause of premature ovarian insufficiency (POI), the mechanism(s) underlying this process have not been elucidated. Recently, androgens were shown to promote oocyte maturation and to play a role in folliculogenesis. In addition, several reports have documented low testosterone levels in the follicular fluid obtained from endometriosis patients. We therefore examined whether the low levels of serum testosterone are associated with the apoptosis of granulosa cells in follicles obtained from endometriosis patients. Serum samples were collected from 46 patients with endometriosis and from 62 patients without endometriosis who received assisted reproductive therapy. Specimens of the ovaries obtained from 10 patients with endometrioma were collected using laparoscopy. The mean serum testosterone concentration in the patients with endometriosis was significantly lower than that observed in the patients without endometriosis. Furthermore, high expression of a pro-apoptotic Bcl-2 member, BimEL, in the follicles was found to be associated with a low serum testosterone level. We clarified the underlying mechanisms using a basic approach employing human immortalized granulosa cells derived from a primary human granulosa cell tumor, the COV434 cell line. The in vitro examination demonstrated that testosterone inhibited apoptosis induced by sex steroids depletion via the PI3K/Akt-FoxO3a pathway in the COV434 cells. In conclusion, we elucidated the mechanism underlying the anti-apoptotic effects of testosterone on granulosa cells, and found that a low-testosterone status is a potentially important step in the development of premature ovarian insufficiency in patients with endometriosis. PMID:25536335
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nichols, R. Charles, E-mail: rnichols@floridaproton.org; University of Florida Proton Therapy Institute, Jacksonville, FL; Morris, Christopher G.
Purpose: Three independent studies of photon (x-ray) radiotherapy (RT) for prostate cancer have demonstrated evidence of testosterone suppression after treatment. The present study was undertaken to determine whether this would also be the case with conformal protons. Methods and Materials: Between August 2006 and October 2007, 171 patients with low- and intermediate-risk prostate cancer were enrolled and underwent treatment according to University of Florida Proton Therapy Institute institutional review board-approved PR01 and PR02 protocols. Of the 171 patients, 18 were excluded because they had received androgen deprivation therapy either before (n = 17) or after (n = 1) RT. Themore » pretreatment serum testosterone level was available for 150 of the remaining 153 patients. These 150 patients were included in the present study. The post-treatment levels were compared with the pretreatment levels. Results: The median baseline pretreatment serum testosterone level was 357.9 ng/dL. The median post-treatment testosterone value was 375.5 ng/dL at treatment completion (p = .1935) and 369.9 ng/dL (p = .1336), 348.7 ng/dL (p = .7317), 353.4 ng/dL (p = .6996), and 340.9 ng/dL (p = .1669) at 6, 12, 18, and 24 months after proton therapy, respectively. Conclusions: Conformal proton therapy to the prostate, as delivered using University of Florida Proton Therapy Institute PR01 and PR02 protocols, did not appear to significantly affect the serum testosterone levels within 24 months after RT.« less
Regulation of Kiss1 Expression by Sex Steroids in the Amygdala of the Rat and Mouse
Kim, Joshua; Semaan, Sheila J.; Clifton, Donald K.; Steiner, Robert A.; Dhamija, Sangeeta
2011-01-01
Kisspeptin (encoded by the Kiss1 gene) is an important regulator of reproduction. In rodents, Kiss1 is expressed in two hypothalamic regions, the arcuate nucleus and anteroventral periventricular/ periventricular continuum, where it is regulated by sex steroids. However, the distribution, regulation, and functional significance of neural kisspeptin outside of the hypothalamus have not been studied and are poorly understood. Here, we report the expression of Kiss1 in the amygdala, predominantly in the medial nucleus of the amygdala (MeA), a region implicated in social and emotional behaviors as well as various aspects of reproduction. In gonadally intact rats and mice, Kiss1-expressing neurons were identified in the MeA of both sexes, with higher Kiss1 expression levels in adult males than females in diestrus. In rats, Kiss1 expression in the MeA changed as a function of the estrous cycle, with highest levels at proestrus. Next, we tested whether Kiss1 in the MeA is regulated by the circulating sex steroid milieu. Kiss1 levels in the MeA were low in gonadectomized mice and rats of both sexes, and treatment with either testosterone or estradiol amplified Kiss1 expression in this region. Testosterone's inductive effect on Kiss1 expression in the MeA likely occurs via estrogen receptor-dependent pathways, not through the androgen receptor, because dihydrotestosterone (a nonaromatizable androgen) did not affect MeA Kiss1 levels. Thus, in rodents, Kiss1 is expressed and regulated by sex steroids in the MeA of both sexes and may play a role in modulating reproduction or brain functions that extend beyond reproduction. PMID:21363930
The use of testosterone as a male contraceptive.
Amory, J K; Bremner, W J
1998-10-01
Testosterone functions as a contraceptive by suppressing secretion of the pituitary gonadotropins luteinizing hormone and follicle stimulating hormone. Low levels of these hormones decrease endogenous testosterone secretion from the testis and deprive developing sperm of the signals required for normal maturation. Interference with sperm maturation causes a decline in sperm production and can lead to reversible infertility in men, raising the possibility that testosterone could be utilized in a commercially available contraceptive. To this end, testosterone has been studied alone and in combination with either gonadotropin releasing hormone analogues or progestins in efforts to improve its contraceptive efficacy. In this chapter, we will review efforts to use testosterone to create a safe, convenient, efficacious contraceptive method for men.
The association of latent toxoplasmosis and level of serum testosterone in humans.
Zouei, Nima; Shojaee, Saeedeh; Mohebali, Mehdi; Keshavarz, Hossein
2018-06-08
Latent toxoplasmosis modifies various hormones and behaviors in infected hosts and possibly involves in etiology of different neurologic and psychiatric disorders. The aim of the current study was to assess possible associations between latent toxoplasmosis and testosterone concentration in Toxoplasma infected and free subjects. Briefly, 18-49 year-old participated in the study. After collected blood samples, sera were analyzed for the detection of anti-Toxoplasma IgG antibody. Totally, 76 positive sera were selected as study group (38 from men and 38 from women) and a same number of negative sera as control group. Comparison of testosterone concentrations and control groups showed that testosterone concentration in study group was higher than that in control group with statistically significant difference (P = 0.024 and P = 0.043 for men and women, respectively). Significant differences were found in testosterone concentrations and anti-Toxoplasma IgG antibody levels in study and control groups (P < 0.05). Toxoplasmosis can affect the mean concentration of serum testosterone in human. Alteration of testosterone during latent toxoplasmosis can result in alterations in behavioral, physiologic and immunological parameters in long time.
Martina, Valentino; Benso, Andrea; Gigliardi, Valentina Ramella; Masha, Andi; Origlia, Carla; Granata, Riccarda; Ghigo, Ezio
2006-03-01
Several clinical and population-based studies suggest that dehydroepiandrosterone (DHEA) and its sulphate (DHEA-S) play a protective role against atherosclerosis and coronary artery disease in human. However, the mechanisms underlying this action are still unknown. It has recently been suggested that DHEA-S could delay atheroma formation through an increase in nitric oxide (NO) production. Twenty-four aged male subjects [age (mean +/- SEM): 65.4 +/- 0.7 year; range: 58.2-67.6 years] underwent a blinded placebo controlled study receiving DHEA (50 mg p.o. daily at bedtime) or placebo for 2 months. Platelet cyclic guanosine-monophosphate (cGMP) concentration (as marker of NO production) and serum levels of DHEA-S, DHEA, IGF-I, insulin, glucose, oestradiol (E(2)), testosterone, plasminogen activator inhibitor (PAI)-1 antigen (PAI-1 Ag), homocysteine and lipid profile were evaluated before and after the 2-month treatment with DHEA or placebo. At the baseline, all variables in the two groups were overlapping. All parameters were unchanged after treatment with placebo. Conversely, treatment with DHEA (a) increased (P < 0.001 vs. baseline) platelet cGMP (111.9 +/- 7.1 vs. 50.1 +/- 4.1 fmol/10(6) plts), DHEA-S (13.6 +/- 0.8 vs. 3.0 +/- 0.3 micromol/l), DHEA (23.6 +/- 1.7 vs. 15.3 +/- 1.4 nmol/l), testosterone (23.6 +/- 1.0 vs. 17.7 +/- 1.0 nmol/l) and E(2) (72.0 +/- 5.0 vs. 60.0 +/- 4.0 pmol/l); and (b) decreased (P < 0.05 vs. baseline) PAI-1 Ag (27.4 +/- 3.8 vs. 21.5 +/- 2.5 ng/ml) and low-density lipoprotein (LDL) cholesterol (3.4 +/- 0.2 vs. 3.0 +/- 0.2 mmol/l). IGF-I, insulin, glucose, triglycerides, total cholesterol, HDL cholesterol, HDL2 cholesterol, HDL3 cholesterol, apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB) and homocysteine levels were not modified by DHEA treatment. This study shows that short-term treatment with DHEA increased platelet cGMP production, a marker of NO production, in healthy elderly subjects. This effect is coupled with a decrease in PAI-1 and LDL cholesterol levels as well as an increase in testosterone and E(2) levels. These findings, therefore, suggest that chronic DHEA supplementation would exert antiatherogenic effects, particularly in elderly subjects who display low circulating levels of this hormone.
Pharmacologic basis for the enhanced efficacy of dutasteride against prostatic cancers.
Xu, Yi; Dalrymple, Susan L; Becker, Robyn E; Denmeade, Samuel R; Isaacs, John T
2006-07-01
Prostatic dihydrotestosterone (DHT) concentration is regulated by precursors from systemic circulation and prostatic enzymes of androgen metabolism, particularly 5alpha-reductases (i.e., SRD5A1 and SRD5A2). Therefore, the levels of expression SRD5A1 and SRD5A2 and the antiprostatic cancer growth response to finasteride, a selective SRD5A2 inhibitor, versus the dual SRD5A1 and SRD5A2 inhibitor, dutasteride, were compared. Real-time PCR and enzymatic assays were used to determine the levels of SRD5A1 and SRD5A2 in normal versus malignant rat and human prostatic tissues. Rats bearing the Dunning R-3327H rat prostate cancer and nude mice bearing LNCaP or PC-3 human prostate cancer xenografts were used as model systems. Tissue levels of testosterone and DHT were determined using liquid chromatography-mass spectrometry. Prostate cancer cells express undetectable to low levels of SRD5A2 but elevated levels of SRD5A1 activity compared with nonmalignant prostatic tissue. Daily oral treatment of rats with the SRD5A2 selective inhibitor, finasteride, reduces prostate weight and DHT content but did not inhibit R-3327H rat prostate cancer growth or DHT content in intact (i.e., noncastrated) male rats. In contrast, daily oral treatment with even a low 1 mg/kg/d dose of the dual SRD5A1 and SRD5A2 inhibitor, dutasteride, reduces both normal prostate and H tumor DHT content and weight in intact rats while elevating tissue testosterone. Daily oral treatment with finasteride significantly (P < 0.05) inhibits growth of LNCaP human prostate cancer xenografts in intact male nude mice, but this inhibition is not as great as that by equimolar oral dosing with dutasteride. This anticancer efficacy is not equivalent, however, to that produced by castration. Only combination of dutasteride and castration produces a greater tumor inhibition (P < 0.05) than castration monotherapy against androgen-responsive LNCaP cancers. In contrast, no response was induced by dutasteride in nude mice bearing androgen-independent PC-3 human prostatic cancer xenografts. These results document that testosterone is not as potent as DHT but does stimulate prostate cancer growth, thus combining castration with dutasteride enhances therapeutic efficacy.
Wu, Yue; Godoy, Alejandro; Azzouni, Faris; Wilton, John H; Ip, Clement; Mohler, James L
2013-09-01
Blocking 5α-reductase-mediated testosterone conversion to dihydrotestosterone (DHT) with finasteride or dutasteride is the driving hypothesis behind two prostate cancer prevention trials. Factors affecting intracellular androgen levels and the androgen receptor (AR) signaling axis need to be examined systematically in order to fully understand the outcome of interventions using these drugs. The expression of three 5α-reductase isozymes, as determined by immunohistochemistry and qRT-PCR, was studied in five human prostate cancer cell lines. Intracellular testosterone and DHT were analyzed using mass spectrometry. A luciferase reporter assay and AR-regulated genes were used to evaluate the modulation of AR activity. Prostate cancer cells were capable of accumulating testosterone to a level 15-50 times higher than that in the medium. The profile and expression of 5α-reductase isozymes did not predict the capacity to convert testosterone to DHT. Finasteride and dutasteride were able to depress testosterone uptake in addition to lowering intracellular DHT. The inhibition of AR activity following drug treatment often exceeded the expected response due to reduced availability of DHT. The ability to maintain high intracellular testosterone might compensate for the shortage of DHT. The biological effect of finasteride or dutasteride appears to be complex and may depend on the interplay of several factors, which include testosterone turnover, enzymology of DHT production, ability to use testosterone and DHT interchangeably, and propensity of cells for off-target AR inhibitory effect. © 2013 Wiley Periodicals, Inc.
Kim, Jin Wook; Oh, Mi Mi; Yoon, Cheol Yong; Bae, Jae Hyun; Kim, Je Jong; Moon, Du Geon
2014-05-01
To investigate the putative association between nocturia and decreased serum testosterone in men with lower urinary tract symptoms. Frequency volume charts and serum testosterone levels of patients visiting the outpatient clinic for lower urinary tract symptoms were collected and analyzed. Age, prostate volume, body mass index and the presence of comorbidities were accounted for. Frequency volume charts were analyzed for pathophysiological components of nocturnal polyuria, global polyuria, decreased nocturnal bladder capacity and increased frequency to identify associated risks. Frequency volume charts were also used to chart 8-h changes of volume, frequency and capacity to identify time diurnal interactions with risk factors based on serum testosterone levels. A total of 2180 patients were enrolled in the study. Multivariate analysis showed testosterone decreased 0.142 ng/mL for every increase in nocturia, independent of other factors. Logistic regression analysis showed a significant difference between pathophysiological components. Decreased testosterone was shown to carry a significant independent risk for overall nocturia (odds ratio 1.60, 95% confidence interval 1.013-2.527, P = 0.044), and particularly nocturnal polyuria (odds ratio 1.934, 95% confidence interval 1.001-3.737, P = 0.027). Repeated measurement models showed patients with serum testosterone below 2.50 ng/mL to have a paradoxical increase in nocturnal urine volume at night. Nocturia, especially nocturnal polyuria, is associated with decreased serum testosterone. Patients with low serum testosterone show increased nocturnal urine output. © 2013 The Japanese Urological Association.
Ambroziak, Urszula; Kuryłowicz, Alina; Kępczyńska-Nyk, Anna; Kondracka, Agnieszka; Gajda, Sylvia; Sieńko, Damian
2018-06-01
The diagnosis of biochemical hyperandrogenism is still challenging because a set of appropriate, recommended diagnostic tests has not been established. In our study, we aimed to answer the question of whether salivary testosterone is a reliable test to establish the diagnosis of biochemical hyperandrogenism as compared to serum total testosterone (TT) measured either by liquid chromatography-tandem mass spectrometry (LC-MS/MS) or immunoassay and to assess which set of biochemical tests would be the most appropriate for the identification of biochemical hyperandrogenism. A total of 39 women, aged 18-45 years, with clinical or biochemical hyperandrogenism and 41 healthy individuals, aged 19-45 years, were enrolled in the study. Salivary testosterone was measured using the Salimetrics test. Serum TT was measured either using the LC-MS/MS method or immunoassay, and dehydroepiandrosterone sulphate (DHEA-S) and androstenedione were measured using LC-MS/MS. In 15 of 17 (88%) patients with elevated serum TT measured by LC-MS/MS and in 14 of 16 (87%) measured with immunoassay, salivary testosterone showed normal levels. In 11 of 39 women (28%) with normal serum testosterone levels, DHEA-S was elevated. All patients with elevated androstenedione presented with an elevated concentration of either serum testosterone or DHEA-S. Salivary testosterone measurement may lead to the underdiagnosis of biochemical hyperandrogenism. Both serum testosterone and DHEA-S should be measured in the endocrine work-up toward biochemical hyperandrogenism. © 2018 Japan Society of Obstetrics and Gynecology.
Testosterone Trajectories and Reference Ranges in a Large Longitudinal Sample of Male Adolescents
Khairullah, Ammar; Cousino Klein, Laura; Ingle, Suzanne M.; May, Margaret T.; Whetzel, Courtney A.; Susman, Elizabeth J.; Paus, Tomáš
2014-01-01
Purpose Pubertal dynamics plays an important role in physical and psychological development of children and adolescents. We aim to provide reference ranges of plasma testosterone in a large longitudinal sample. Furthermore, we describe a measure of testosterone trajectories during adolescence that can be used in future investigations of development. Methods We carried out longitudinal measurements of plasma testosterone in 2,216 samples obtained from 513 males (9 to 17 years of age) from the Avon Longitudinal Study of Parents and Children. We used integration of a model fitted to each participant’s testosterone trajectory to calculate a measure of average exposure to testosterone over adolescence. We pooled these data with corresponding values reported in the literature to provide a reference range of testosterone levels in males between the ages of 6 and 19 years. Results The average values of total testosterone in the ALSPAC sample range from 0.82 nmol/L (Standard Deviation [SD]: 0.09) at 9 years of age to 16.5 (SD: 2.65) nmol/L at 17 years of age; these values are congruent with other reports in the literature. The average exposure to testosterone is associated with different features of testosterone trajectories such as Peak Testosterone Change, Age at Peak Testosterone Change, and Testosterone at 17 years of age as well as the timing of the growth spurt during puberty. Conclusions The average exposure to testosterone is a useful measure for future investigations using testosterone trajectories to examine pubertal dynamics. PMID:25268961
Morgentaler, Abraham; Polzer, Paula; Althof, Stanley; Bolyakov, Alexander; Donatucci, Craig; Ni, Xiao; Patel, Ankur B; Basaria, Shehzad
2017-09-01
Although delayed ejaculation (DE) is typically characterized as a persistently longer than anticipated or desired time to ejaculation (or orgasm) during sexual activity, a timing-based definition of DE and its association with serum testosterone has not been established in a large cohort. To examine in an observational study estimated intravaginal ejaculatory latency time (IELT) and masturbatory ejaculation latency time (MELT) in men self-reporting DE, assess the association of IELT and MELT with serum testosterone levels, and determine whether correlation with demographic and sexual parameters exist. Men who resided in the United States, Canada, and Mexico were enrolled from 2011 to 2013. Self-estimated IELT and MELT were captured using an Ejaculatory Function Screening Questionnaire in a sample of 988 men screened for possible inclusion in a randomized clinical trial assessing testosterone replacement therapy for ejaculatory dysfunction (EjD) and who self-reported the presence or absence of DE and symptoms of hypogonadism. Additional comorbid EjDs (ie, anejaculation, perceived decrease in ejaculate volume, and decreased force of ejaculation) were recorded. Men with premature ejaculation were excluded from this analysis. IELT and MELT were compared between men self-reporting DE and men without DE. The associations of IELT and MELT with serum testosterone were measured. IELT, MELT, and total testosterone levels. Sixty-two percent of screened men self-reported DE with or without comorbid EjDs; 38% did not report DE but did report at least one of the other EjDs. Estimated median IELTs were 20.0 minutes for DE vs 15 minutes for no DE (P < .001). Estimated median MELTs were 15.0 minutes for DE vs 8.0 minutes for no DE (P < .001). Ejaculation time was not associated with serum testosterone levels. Younger men and those with less severe erectile dysfunction had longer IELTs and MELTs. Estimated ejaculation times during vaginal intercourse and/or masturbation were not associated with serum testosterone levels in this study; thus, routine androgen evaluation is not indicated in these men. This large systematic analysis attempted to objectively assess the ejaculation latency in men with self-reported DE. Limitations were that ejaculation time estimates were self-reported and were queried only once; the questionnaire did not distinguish between failure to achieve orgasm and ejaculation; and assessment of DE was limited to heterosexual vaginal intercourse and masturbation. IELT and MELT were longer in men with DE, and there was no association of ejaculation times with serum testosterone levels in this study population. Morgentaler A, Polzer P, Althof S, et al. Delayed Ejaculation and Associated Complaints: Relationship to Ejaculation Times and Serum Testosterone Levels. J Sex Med 2017;14:1116-1124. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Endocrine events associated with spawning behavior in the sea lamprey (Petromyzon marinus)
Linville, Jane E.; Hanson, Lee H.; Sower, Stacia A.
1987-01-01
Levels of estradiol, progesterone, and testosterone were determined in plasma of sea lamprey (Petromyzon marinus) undergoing certain behaviors associated with spawning in natural and artifical stream environments. Significantly higher levels of estradiol, progesterone, and testosterone were found in males than in females. In the artifical spawning channel, levels of estradiol were significantly higher in females exhibiting resting and swimming behaviors than in fanning, nest building, and spawning behaviors. No significant correlation was found with either progesterone or testosterone levels and the various reproductive behaviors. The data presented are the first experimental evidence that suggest gonadal steroids may be correlated with certain reproductive behaviors in the sea lamprey.
Wu, Frederick; Zitzmann, Michael; Heiselman, Darell; Donatucci, Craig; Knorr, Jack; Patel, Ankur B; Kinchen, Kraig
2016-08-01
Evidence from well-designed studies documenting the benefit of testosterone replacement therapy as a function of patient demographic and clinical characteristics is lacking. To determine demographic and clinical predictors of treatment outcomes in hypogonadal men with low sex drive, low energy, and/or erectile dysfunction. Post hoc analysis of a randomized, multicenter, double-blinded, placebo-controlled, 16-week study of 715 hypogonadal men (mean age = 55.3 years, age range = 19-92 years) presenting with low sex drive and/or low energy who received placebo or testosterone solution 2% for 12 weeks. Two levels defined patient-reported improvement (PRI) in sex drive or energy: level 1 was at least "a little better" and level 2 was at least "much better" in energy or sex drive on the Patient Global Impression of Improvement at study end point. PRI in erectile function was stratified by erectile dysfunction severity at baseline as measured by the erectile function domain of the International Index for Erectile Function: mild at baseline (change of 2), moderate at baseline (change of 5), and severe at baseline (change of 7). Associations of demographic and clinical characteristics with PRI were calculated with stepwise forward multiple logistic regression analysis. Odds ratios represented the likelihood of PRI in symptoms among variable categories. Higher levels of end-point testosterone were associated with higher rates of PRI (at levels 1 and 2) in sex drive and energy (P < .001 for the two comparisons). Lower baseline testosterone levels were associated with higher rates of level 1 PRI in sex drive (P = .028); and classic hypogonadism (vs non-classic hypogonadism) was associated with higher rates of level 2 PRI in sex drive (P = .005) and energy (P = .006). When assessing the potential for improvements in men with testosterone deficiency using patient-reported outcome questionnaires, possible predictors of treatment outcomes to consider include the etiology of hypogonadism and testosterone levels (baseline and end point). Copyright © 2016. Published by Elsevier Inc.
Reduction of spermatogonia and testosterone in rat testes flown on Space Lab-3
NASA Technical Reports Server (NTRS)
Philpott, Delbert E.; Stevenson, J.; Black, S.; Sapp, W.; Williams, C.
1986-01-01
The effects of space flight on rat testes were investigated. The weight, spermatogonial cell count, and testosterone levels in six rats flown on Space Lab-3 were measured. It is observed that compared to ground control rats the average weight loss was 7.1 percent and the spermatogonial cell count decreased by 7.5 percent. The data reveal that the testosterone level for large control rats was 9.13 ng/ml and 0.31 ng/ml for flight rats; and 2.54 ng/ml and 0.233 ng/ml for smaller control and flight rats, respectively. It is noted that spermatogenesis and testosterone production are reduced during spaceflight.
Influence of testosterone gel treatment on spermatogenesis in men with hypogonadism.
George, Mskhalaya; Yulia, Tishova; Svetlana, Kalinchenko
2014-10-01
The prevalence of androgen deficiency in reproductive-aged men is increasing and needs new approach to long-term hypogonadism treatment that can preserve fertility. An open non-controlled pilot study included 18 men with eugonadotropic hypogonadism, who received transdermal testosterone gel treatment for 3 months. Sperm analysis was made before treatment and after 3 month of testosterone therapy. Testosterone level was normalized in all patients, but no negative effect was observed on spermatogenesis. Testosterone gel therapy may be a therapy of choice in hypogonadal men of reproductive age but further studies are needed.
Scaia, María Florencia; Morandini, Leonel; Noguera, CristobalAlejandro; Trudeau, Vance L; Somoza, Gustavo Manuel; Pandolfi, Matías
2018-06-20
Territorial aggression has been widely studied in males and it has been historically suggested that androgens are key mediators of this behavior. However, more recent evidence suggests that it is the aromatization to estrogens, rather than androgens themselves, that is key to regulating this behavior. Females also display aggressive behaviors, but the physiological regulation of female aggression is still understudied when compared to males. In this context, the challenge hypothesis postulates that male-male aggressive interactions stimulate the production of androgens in males in periods of social instability. Here we determine plasma sex steroid levels in Cichlasoma dimerus to assess whether estrogens are related to aggressive behavior and to test the challenge hypothesis in both males and females. We set-up challenge trials as intrasexual dyadic encounters and determined androgen and estrogen levels before and after the trial in both winners and losers. Even though there were no differences in initial estradiol-17β plasma levels between male winners and losers, initial levels were higher (p = .046) in female winners than in losers, while there were no differences in testosterone or 11-ketotestosterone levels. After trials, both males and females showed elevated levels of estradiol-17β and both androgens, but only males exhibited a significant 1.45, 5.42 and 3.2-fold increase in estradiol-17β, testosterone and 11-ketotestosterone, respectively (p = .023, p = .016, p = .018). Moreover, changes in circulating levels of estradiol-17β in females after the trials do not depend on their reproductive status or on the outcome of the contest. We suggest that female aggression is associated with initial levels of estradiol-17β, and that the challenge hypothesis, originally defined for androgens, could also be extended to estrogens. Copyright © 2018. Published by Elsevier Inc.
Roaiah, Mohamed Farid; Elkhayat, Yasser Ibrahim; Saleh, Sameh Fayek GamalEl Din; Abd El Salam, Mohamed Ahmed
2016-06-23
We evaluated the role of Tribulus terrestris in males with unexplained infertility and its effect on serum testosterone and semen parameters. Thirty randomized male patients presenting to Andrology outpatient clinic complaining of idiopathic infertility were selected. They were given Tribulus terrestris (750 mg) in three divided doses for three months. The effect of Tribulus terrestris on serum testosterone (total and free) and luteinizing hormone (LH), as well as its impact on semen parameters in those patients, was studied. No statistically significant difference was observed in the levels of testosterone (total and free) and LH and semen parameters (sperm concentration or motility, or abnormal forms) before and after the treatment. In addition, no statistically significant correlations were observed between testosterone (free and total) and LH and semen parameters before and after the treatment. Tribulus terrestris was ineffective in the treatment of idiopathic infertility.
NASA Astrophysics Data System (ADS)
Zhou, Yi; Tan, Xin; Zhu, Bao-an; Qi, Meng-di; Ding, Su-ling
Space flight and simulated microgravity lead to suppression of mammalian spermatogenesis and decreased plasma testosterone level. In order to explain the mechanism behind the depression, we used rat tail-suspended model to simulate weightless conditions. To prevent cryptorchidism caused by tail-suspension, some experimental animals received inguinal canal ligation. The results showed that mass of testis decreased significantly and seminiferous tubules became atrophied in rats after tail-suspension. The levels of plasma testosterone (T), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in tail-suspended rats with or without inguinal canal ligation decreased significantly compared with controls, and an increased level of plasma estradiol (E) was revealed in tail-suspended rats. The results indicate that besides the direct influence of fluid shift upon testis under short-term simulated microgravity, the pituitary function is also disturbed as a result of either immobilization stress or weight loss during tail-suspension treatment, which is responsible to some extent for the decreased testosterone secretion level and the atrophia of testis. The conversion of testosterone into E under simulated microgravity is another possible cause for the decline of plasma testosterone.
Roaiah, Mohamed Farid; El Khayat, Yasser Ibrahim; GamalEl Din, Sameh Fayek; Abd El Salam, Mohamed Ahmed
2016-05-18
This study was conducted on 30 consecutive male patients presenting to Kasr-Al Ainy Andrology outpatient clinic complaining of manifestations of partial androgen deficiency in aging males (PADAM). In this study (750 mg/day) of Tribulus terrestris in 3 divided doses, each of 250 mg, as an endogenous testosterone enhancer had been tried for a duration of 3 months and the evaluation of its effect had been monitored for each patient concerning its effect on serum testosterone (total and free) and luteinizing hormone (LH), as well as its impact on erectile function, which was evaluated by the International Index of Erectile Function-5 (IIEF-5) questionnaire for those patients. Results showed a statistically significant difference in the level of testosterone (total and free) and IIEF-5, but no statistically significant difference in the level of LH before and after treatment. Also, the study showed statistically significant correlation between testosterone (total and free) and IIEF-5, but no statistically significant correlation between the level of LH and the IIEF-5 before and after treatment.
Zöttl, Markus; Vullioud, Philippe; Goddard, Katy; Torrents-Ticó, Miquel; Gaynor, David; Bennett, Nigel C; Clutton-Brock, Tim
2018-05-02
In Damaraland mole-rats (Fukomys damarensis), non-breeding subordinates contribute to the care of offspring born to the breeding pair in their group by carrying and retrieving young to the nest. In social mole-rats and some cooperative breeders, dominant females show unusually high testosterone levels and it has been suggested that high testosterone levels may increase reproductive and aggressive behavior and reduce investment in allo-parental and parental care, generating age and state-dependent variation in behavior. Here we show that, in Damaraland mole-rats, allo-parental care in males and females is unaffected by experimental increases in testosterone levels. Pup carrying decreases with age of the non-breeding helper while the change in social status from non-breeder to breeder has contrasting effects in the two sexes. Female breeders were more likely than female non-breeders to carry pups but male breeders were less likely to carry pups than male non-breeders, increasing the sex bias in parental care compared to allo-parental care. Our results indicate that testosterone is unlikely to be an important regulator of allo-parental care in mole-rats. Copyright © 2018. Published by Elsevier Inc.
Blick, Gary
2013-03-01
To determine the incidence of hypogonadism in men with human immunodeficiency virus (HIV)/acquired immunodeficiency virus (AIDS), the most useful serum testosterone measurement and threshold for diagnosing hypogonadism, and the comparative efficacy of 2 testosterone replacement therapy (TRT) 1% gels (AndroGel® [Abbott Laboratories] and Testim® [Auxilium Pharmaceuticals, Inc.]). This was a 2-stage observational study. In stage 1, patient records from 2 medical practices specializing in HIV/AIDS were reviewed. Eligible patients were aged ≥ 18 years; had HIV-seropositive status confirmed by enzyme-linked immunosorbent assay and western blot test or HIV-1 viremia confirmed by HIV-1 RNA polymerase chain reaction; and had prior baseline testosterone assessments for hypogonadism (ie, presence of signs/symptoms of hypogonadism as well as total testosterone [TT] and free testosterone [FT] level measurements). Stage 2 included the evaluation of patients from stage 1 who were treated with 5 to 10 g/day of TRT. The stage 2 inclusion criteria were a diagnosis of low testosterone (defined as TT level < 300 ng/dL and/or FT level < 50 pg/mL, as per The Endocrine Society guidelines and presence/absence of hypogonadal signs and symptoms); ≥ 12 months of evaluable sign and symptom assessments and TT/FT level measurements while on TRT with either Testim® or AndroGel®; and ≥ 4 weeks on initial TRT if the initial TRT was switched or discontinued. Four hundred one of 422 patients met the stage 1 inclusion criteria and 167 of 401 patients (AndroGel®, n = 92; Testim®, n = 75) met the stage 2 inclusion criteria. Total testosterone level < 300 ng/dL alone identified 24% (94 of 390) of patients as hypogonadal, but failed to diagnose an additional 111 patients (67.7%) with FT levels < 100 pg/mL and hypogonadal symptoms. Through month 12, AndroGel® increased mean TT levels by +42.8% and FT levels by +66.9%, compared with +178.7% (P = 0.017) and +191% (P = 0.039), respectively, for Testim®. Patients treated with Testim® showed significantly greater improvements in libido, sexual performance, nighttime energy, focus/concentration, and abdominal girth, and trends for greater improvement in fatigue and erectile dysfunction than patients treated with AndroGel®. No patients discontinued therapy due to adverse events. The most useful serum testosterone measurement and threshold for diagnosing hypogonadism in men with HIV/AIDS was FT level < 100 pg/mL, which identified 64% of men as hypogonadal with the presence of ≥ 1 hypogonadal symptom. This is above currently accepted thresholds. Criteria using TT level < 300 ng/dL and FT level < 50 pg/mL only diagnosed 24% and 19% of patients, respectively, as having hypogonadism. Testim® was more effective than AndroGel® in increasing TT and FT levels and improving hypogonadal symptoms.
Low testosterone levels in elderly men with dysthymic disorder.
Seidman, Stuart N; Araujo, Andre B; Roose, Steven P; Devanand, D P; Xie, Shan; Cooper, Thomas B; McKinlay, John B
2002-03-01
A decline in hypothalamic-pituitary-gonadal (HPG) axis function is often seen in elderly men, and dysthymic disorder is common. Symptoms of both HPG axis hypofunction and dysthymic disorder include dysphoria, fatigue, and low libido. The authors compared total testosterone levels in three groups of elderly men. Total testosterone levels were measured in subjects who met DSM-IV criteria for major depressive disorder (N=13) or dysthymic disorder (N=32) and a comparison group (N=175) who had participated in an epidemiological study of male aging and had scored below the median on the Center for Epidemiologic Studies Depression Scale, a well-validated, self-report depression symptom inventory. There were no differences among the three groups in measured demographic variables, including age and weight. Median testosterone levels varied for those with dysthymic disorder (295 ng/dl), major depressive disorder (425 ng/dl), and no depression (423 ng/dl). A test for differences in central tendency showed a statistically significant difference among the three groups. Post hoc pairwise comparisons revealed statistically significant differences between those with dysthymic disorder and those with major depressive disorder and no depression. Total testosterone levels were lower in elderly men with dysthymic disorder than in men with major depressive disorder and men without depressive symptoms. Dysthymic disorder in elderly men may be related to HPG axis hypofunction.
Luo, Mai; Hua, Yifan; Liang, Yiran; Han, Jiajun; Liu, Donghui; Zhao, Wenting; Wang, Peng
2017-12-15
A novel functionalized carbon dot has been synthesized by covalently linking β-cyclodextrin to the surface of N, S codoped carbon dots (β-CD-CDs). The characterization was confirmed by transmission electron microscopy, X-ray photoelectron spectroscopy, infrared spectra, ultraviolet-visible, and fluorescence emission spectra. On the basis of this carbon dot and (ferrocenylmethyl) trimethylammonium iodide (Fc + ), a photo-induced electron transfer (PET) fluorescent probe system was developed to determine the concentration of testosterone in water and identify testosterone in cell by fluorescence imaging as a visible biomarker. Under the optimum condition, the fluorescent intensity of the probe system linearly responded to the concentration of testosterone from 0μM to 280μM and the limit of detection was 0.51μM. This probe system also performed well at determining testosterone in groundwater with average recoveries of testosterone ranging from 96% to 107% at spiking levels of 0.5-100μM, and the relative standard deviation remained below 13%, which provided a reliable, rapid and easy method to determine testosterone in environmental water. Furthermore, the low cytotoxicity, high anti-interference ability, and excellent biocompatibility of β-CD-CDs made this probe system successfully used in cell fluorescence imaging to monitor levels of testosterone in the cytoplasm of cells with a promising application value in medical research. Copyright © 2017 Elsevier B.V. All rights reserved.
Eriksen, Mette Brandt; Glintborg, Dorte; Nielsen, Michael Friberg Bruun; Jakobsen, Marianne Antonius; Brusgaard, Klaus; Tan, Qihua; Gaster, Michael
2014-09-05
Polycystic ovary syndrome (PCOS) is associated with insulin resistance and increased risk of type 2 diabetes. Skeletal muscle is the major site of insulin mediated glucose disposal and the skeletal muscle tissue is capable to synthesize, convert and degrade androgens. Insulin sensitivity is conserved in cultured myotubes (in vitro) from patients with PCOS, but the effect of testosterone on this insulin sensitivity is unknown. We investigated the effect of 7days testosterone treatment (100nmol/l) on glucose transport and gene expression levels of hormone receptors and enzymes involved in the synthesis and conversion of testosterone (HSD17B1, HSD17B2, CYP19A1, SRD5A1-2, AR, ER-α, HSD17B6 and AKR1-3) in myotubes from ten patients with PCOS and ten matched controls. Testosterone treatment significantly increased aromatase and androgen receptor gene expression levels in patients and controls. Glucose transport in myotubes was comparable in patients with PCOS vs. controls and was unchanged by testosterone treatment (p=0.21 PCOS vs. controls). These results suggest that testosterone treatment of myotubes increases the aromatase and androgen receptor gene expression without affecting insulin sensitivity and if testosterone is implicated in muscular insulin resistance in PCOS, this is by and indirect mechanism. Copyright © 2014 Elsevier Inc. All rights reserved.
Testosterone affects language areas of the adult human brain.
Hahn, Andreas; Kranz, Georg S; Sladky, Ronald; Kaufmann, Ulrike; Ganger, Sebastian; Hummer, Allan; Seiger, Rene; Spies, Marie; Vanicek, Thomas; Winkler, Dietmar; Kasper, Siegfried; Windischberger, Christian; Swaab, Dick F; Lanzenberger, Rupert
2016-05-01
Although the sex steroid hormone testosterone is integrally involved in the development of language processing, ethical considerations mostly limit investigations to single hormone administrations. To circumvent this issue we assessed the influence of continuous high-dose hormone application in adult female-to-male transsexuals. Subjects underwent magnetic resonance imaging before and after 4 weeks of testosterone treatment, with each scan including structural, diffusion weighted and functional imaging. Voxel-based morphometry analysis showed decreased gray matter volume with increasing levels of bioavailable testosterone exclusively in Broca's and Wernicke's areas. Particularly, this may link known sex differences in language performance to the influence of testosterone on relevant brain regions. Using probabilistic tractography, we further observed that longitudinal changes in testosterone negatively predicted changes in mean diffusivity of the corresponding structural connection passing through the extreme capsule. Considering a related increase in myelin staining in rodents, this potentially reflects a strengthening of the fiber tract particularly involved in language comprehension. Finally, functional images at resting-state were evaluated, showing increased functional connectivity between the two brain regions with increasing testosterone levels. These findings suggest testosterone-dependent neuroplastic adaptations in adulthood within language-specific brain regions and connections. Importantly, deteriorations in gray matter volume seem to be compensated by enhancement of corresponding structural and functional connectivity. Hum Brain Mapp 37:1738-1748, 2016. © 2016 Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
Estradiol and Inflammatory Markers in Older Men
Maggio, Marcello; Ceda, Gian Paolo; Lauretani, Fulvio; Bandinelli, Stefania; Metter, E. Jeffrey; Artoni, Andrea; Gatti, Elisa; Ruggiero, Carmelinda; Guralnik, Jack M.; Valenti, Giorgio; Ling, Shari M.; Basaria, Shehzad; Ferrucci, Luigi
2009-01-01
Background: Aging is characterized by a mild proinflammatory state. In older men, low testosterone levels have been associated with increasing levels of proinflammatory cytokines. It is still unclear whether estradiol (E2), which generally has biological activities complementary to testosterone, affects inflammation. Methods: We analyzed data obtained from 399 men aged 65–95 yr enrolled in the Invecchiare in Chianti study with complete data on body mass index (BMI), serum E2, testosterone, IL-6, soluble IL-6 receptor, TNF-α, IL-1 receptor antagonist, and C-reactive protein. The relationship between E2 and inflammatory markers was examined using multivariate linear models adjusted for age, BMI, smoking, physical activity, chronic disease, and total testosterone. Results: In age-adjusted analysis, log (E2) was positively associated with log (IL-6) (r = 0.19; P = 0.047), and the relationship was statistically significant (P = 0.032) after adjustments for age, BMI, smoking, physical activity, chronic disease, and serum testosterone levels. Log (E2) was not significantly associated with log (C-reactive protein), log (soluble IL-6 receptor), or log (TNF-α) in both age-adjusted and fully adjusted analyses. Conclusions: In older men, E2 is weakly positively associated with IL-6, independent of testosterone and other confounders including BMI. PMID:19050054