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Androgen Levels (androgen + level)

Distribution by Scientific Domains

Medical Sciences	63%
Life Sciences	36%

Selected Abstracts

Determinants of within- and among-clutch variation in levels of maternal hormones in Black-Headed Gull eggs

FUNCTIONAL ECOLOGY, Issue 3 2002
Groothuis T. G.
Summary 1.,Females of egg-laying vertebrates may adjust the development of their offspring to prevailing environmental conditions by regulating the deposition of hormones into their eggs. Within- and amng-clutch variation in levels of steroid hormones were studied in the egg yolks of the Black-Headed Gull (Larus ridibundus, Linnaeus) in relation to environmental conditions at the nest site. This species breeds in colonies of different densities and in different habitats, and the chicks hatch asynchronously. 2.,Egg yolks contained very high levels of androstenedione, substantial levels of testosterone and moderate levels of 5,-dihydrotestosterone. Oestrogen (17,-oestradiol) was not detected. 3.,Androgen levels increased strongly with laying order, irrespective of egg or yolk mass. This may compensate for the disadvantages of the later hatching chicks. These results have implications for adaptive hypotheses that were proposed for asynchronous incubation. 4.,Eggs of lighter clutches contained more androgens, perhaps to compensate for a lower nutritional quality of these eggs. 5.,Birds breeding in the periphery of a colony, being relatively more aggressive and having relatively large territories, laid eggs that contained more androgens than those of birds breeding in the centre. These high yolk androgen levels may facilitate growth and motor development of the chicks, which may be especially important for chicks developing at the periphery of a colony. Reduced levels may be adaptive for birds breeding in the centre, where risk of infectious diseases is high, since steroids may be immunosuppressive. 6.,Corrected for nest distance, clutches of birds in high vegetation, where predation risk is less severe and therefore competition for nest sites perhaps high, contained relatively high levels of androgens. It is suggested that the level of yolk androgens reflects the hormonal condition of the female, that in turn is influenced by her characteristics such as her age and aggressiveness, and the level of social stimulation. [source]

Gender-dependent effect of ageing on peripheral insulin action

INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 4 2005
A-M. Borissova
Summary The aim of the present study was to investigate the effect of both gender and age on insulin secretion, peripheral insulin effectiveness and insulin-receptor binding. Eighty healthy volunteers, 40 females of mean age 38.47 ± 11.37 years and mean BMI 21.99 ± 2.06 kg/m2 and 40 males of mean age 34.87 ± 11.22 years and mean BMI 22.65 ± 2.31 kg/m2, with normal glucose tolerance participated in the study. Peripheral insulin effectiveness was measured by the artificial endocrine pancreas, using the euglycaemic hyperinsulinaemic clamp technique and insulin-receptor binding on circulating mononuclear blood cells. Peripheral insulin sensitivity was significantly higher in females as compared to males (p < 0.001), while males demonstrated higher total number of insulin receptors (p < 0.0001) and number of high-affinity receptors (p < 0.01). Peripheral insulin sensitivity decreased with ageing in both males and females, the reduction in females being more pronounced (p < 0.05). In the group under 40 years, the females demonstrated significantly higher insulin sensitivity as compared to males (p < 0.001) and lower insulin-receptor binding. Over 40 years, females presented higher peripheral insulin sensitivity and higher insulin-receptor binding. The percentage of specifically bound insulin increased significantly with ageing in females and decreased in males. We consider that probably the higher androgen level in males affects the post-receptor processes in insulin action and despite the higher insulin-receptor binding, males have lower insulin sensitivity. The androgen levels in females increase with ageing, which could probably affect peripheral insulin sensitivity at the post-receptor level. In conclusion, our results demonstrate that when analysing peripheral insulin effectiveness and insulin-receptor binding, one should always consider both gender and age. [source]

Sex-role reversal is reflected in the brain of African black coucals (Centropus grillii)

DEVELOPMENTAL NEUROBIOLOGY, Issue 12 2007
Cornelia Voigt
Abstract In most bird species males compete over access to females and have elevated circulating androgen levels when they establish and defend a breeding territory or guard a mate. Testosterone is involved in the regulation of territorial aggression and sexual display in males. In few bird species the traditional sex-roles are reversed and females are highly aggressive and compete over access to males. Such species represent excellent models to study the hormonal modulation of aggressive behavior in females. Plasma sex steroid concentrations in sex-role reversed species follow the patterns of birds with "traditional" sex-roles. The neural mechanisms modulating endocrine secretion and hormone,behavior interactions in sex-role reversed birds are currently unknown. We investigated the sex differences in the mRNA expression of androgen receptors, estrogen receptor ,, and aromatase in two brain nuclei involved in reproductive and aggressive behavior in the black coucal, the nucleus taeniae and the bed nucleus of the stria terminalis. In the bed nucleus there were no sex differences in the receptor or aromatase expression. In the nucleus taeniae, however, we show for the first time, that females have a higher mRNA expression of androgen receptors than males. These results suggest that the expression of agonistic and courtship behavior in females does not depend on elevated blood hormone levels, but may be regulated via increased steroid hormone sensitivity in particular target areas in the brain. Hence, aggression in females and males may indeed be modulated by the same hormones, but regulated at different levels of the neuroendocrine cascade. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007 [source]

Testosterone and dihydrotestosterone, but not estradiol, enhance survival of new hippocampal neurons in adult male rats

DEVELOPMENTAL NEUROBIOLOGY, Issue 10 2007
Mark D. Spritzer
Abstract Past research suggested that androgens may play a role in the regulation of adult neurogenesis within the dentate gyrus. We tested this hypothesis by manipulating androgen levels in male rats. Castrated or sham castrated male rats were injected with 5-Bromo-2,deoxyuridine (BrdU). BrdU-labeled cells in the dentate gryus were visualized and phenotyped (neural or glial) using immunohistochemistry. Castrated males showed a significant decrease in 30-day cell survival within the dentate gyrus but there was no significant change in cell proliferation relative to control males, indicating that androgens positively affect cell survival, but not cell proliferation. To examine the role of testosterone on hippocampal cell survival, males were injected with testosterone s.c. for 30 days starting the day after BrdU injection. Higher doses (0.5 and 1.0 mg/kg) but not a lower dose (0.25 mg/kg) of testosterone resulted in a significant increase in neurogenesis relative to controls. We next tested the role of testosterone's two major metabolites, dihydrotestosterone (DHT), and estradiol, upon neurogenesis. Thirty days of injections of DHT (0.25 and 0.50 mg/kg) but not estradiol (0.010 and 0.020 mg/kg) resulted in a significant increase in hippocampal neurogenesis. These results suggest that testosterone enhances hippocampal neurogenesis via increased cell survival in the dentate gyrus through an androgen-dependent mechanism. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007. [source]

Time-Dependent transcriptional profiles of genes of the hypothalamic-pituitary-gonadal axis in medaka (Oryzias latipes) exposed to fadrozole and 17,-trenbolone

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2008
Xiaowei Zhang
Abstract Both the anabolic androgen 17,-trenbolone (TRB) and the aromatase inhibitor fadrozole (FAD) can cause decreased plasma concentrations of estrogen (E2) and reduce fecundity of fish. However, the underlying mechanisms and the molecular pathways involved are largely unknown. The present study was designed to assess time-dependent effects of FAD and TRB on the transcriptional responses of the hypothalamic-pituitary-gonadal (HPG) axis of Japanese medaka (Oryzias latipes). Fourteen-week-old Japanese medaka were exposed to 50 ,g FAD/L or 2 ,g TRB/L in a 7-d static renewal test, and the expression profiles of 36 HPG axis genes were measured by means of a medaka HPG real-time reverse-transcription polymerase chain reaction array after 8 h, 32 h, or 7 d of exposure. Exposure to TRB or FAD caused lesser fecundity of Japanese medaka and down-regulated transcription of vitellogenin and choriogenin (CHG) gene expression in the liver of females. Exposure to FAD for 8 h resulted in an 8-fold and 71-fold down-regulation of expression of estrogen receptor , and choriogenin L (CHG L), respectively, in female liver. 17,-Trenbolone caused similar down-regulation of these genes, but the effects were not observed until 32 h of exposure. These results support the hypothesis that FAD reduces plasma E2 more quickly by inhibiting aromatase enzyme activity than does TRB, which inhibits the production of the E2 precursor testosterone. Exposure to FAD and TRB resulted in rapid (after 8 h) down-regulation of luteinizing hormone receptor and low-density-lipoprotein receptor in the testis to compensate for excessive androgen levels. Overall, the molecular responses observed in the present study differentiate the mechanisms of the reduced fecundity by TRB and FAD. [source]

Determinants of within- and among-clutch variation in levels of maternal hormones in Black-Headed Gull eggs

The association of plasma androgen levels with breast, ovarian and endometrial cancer risk factors among postmenopausal women

INTERNATIONAL JOURNAL OF CANCER, Issue 1 2010
Kim N. Danforth
Abstract Although androgens may play an etiologic role in breast, ovarian and endometrial cancers, little is known about factors that influence circulating androgen levels. We conducted a cross-sectional analysis among 646 postmenopausal women in the Nurses' Health Study to examine associations between adult risk factors for cancer, including the Rosner/Colditz breast cancer risk score, and plasma levels of testosterone, free testosterone, androstenedione, dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS). All analyses were adjusted for age, laboratory batch and other cancer risk factors. Free testosterone levels were 79% higher among women with a body mass index of ,30 vs. <22 kg/m2 (p -trend <0.01) and 25% higher among women with a waist circumference of >89 vs. ,74 cm (p -trend = 0.02). Consuming >30 g of alcohol a day vs. none was associated with a 31% increase in DHEA and 59% increase in DHEAS levels (p -trend = 0.01 and <0.01, respectively). Smokers of ,25 cigarettes per day had 35% higher androstenedione and 44% higher testosterone levels than never smokers (p -value, F -test = 0.03 and 0.01, respectively). No significant associations were observed for height or time since menopause with any androgen. Testosterone and free testosterone levels were ,30% lower among women with a hysterectomy vs. without (both p -values < 0.01). Overall breast cancer risk was not associated with any of the androgens. Thus, several risk factors, including body size, alcohol intake, smoking and hysterectomy, were related to androgen levels among postmenopausal women, while others, including height and time since menopause, were not. Future studies are needed to clarify further which lifestyle factors modulate androgen levels. [source]

Host sex and ectoparasites choice: preference for, and higher survival on female hosts

JOURNAL OF ANIMAL ECOLOGY, Issue 4 2007
PHILIPPE CHRISTE
Summary 1Sex differences in levels of parasite infection are a common rule in a wide range of mammals, with males usually more susceptible than females. Sex-specific exposure to parasites, e.g. mediated through distinct modes of social aggregation between and within genders, as well as negative relationships between androgen levels and immune defences are thought to play a major role in this pattern. 2Reproductive female bats live in close association within clusters at maternity roosts, whereas nonbreeding females and males generally occupy solitary roosts. Bats represent therefore an ideal model to study the consequences of sex-specific social and spatial aggregation on parasites' infection strategies. 3We first compared prevalence and parasite intensities in a host,parasite system comprising closely related species of ectoparasitic mites (Spinturnix spp.) and their hosts, five European bat species. We then compared the level of parasitism between juvenile males and females in mixed colonies of greater and lesser mouse-eared bats Myotis myotis and M. blythii. Prevalence was higher in adult females than in adult males stemming from colonial aggregations in all five studied species. Parasite intensity was significantly higher in females in three of the five species studied. No difference in prevalence and mite numbers was found between male and female juveniles in colonial roosts. 4To assess whether observed sex-biased parasitism results from differences in host exposure only, or, alternatively, from an active, selected choice made by the parasite, we performed lab experiments on short-term preferences and long-term survival of parasites on male and female Myotis daubentoni. When confronted with adult males and females, parasites preferentially selected female hosts, whereas no choice differences were observed between adult females and subadult males. Finally, we found significantly higher parasite survival on adult females compared with adult males. 5Our study shows that social and spatial aggregation favours sex-biased parasitism that could be a mere consequence of an active and adaptive parasite choice for the more profitable host. [source]

Egg-yolk androgen and carotenoid deposition as a function of maternal social environment in barn swallows Hirundo rustica

JOURNAL OF AVIAN BIOLOGY, Issue 4 2010
Rebecca J. Safran
Evidence is mounting that female animals use egg-yolk compounds (e.g. steroids, antioxidants) to adaptively engineer the quality of their offspring as a function of several maternal and environmental factors. Though adjustments to yolk allocation have been well-characterized as a function of parental phenotypes, we know very little about how an individual's social environment influences yolk composition. Here, we consider how two types of yolk compounds, androgens and carotenoids, relate to the maternal social environment during the egg-laying period, controlling statistically for known correlations between various aspects of parental quality and egg yolk compounds. Barn swallows Hirundo rustica erythrogaster breed in groups of highly variable size and spacing, allowing us to test whether or not the social environment is correlated with these maternal effects. We found no relationship between carotenoid levels in eggs as a function of colony size, colony density, or nearest-neighbor distance. However, eggs from females in larger groups had lower concentrations and total amounts of yolk androgens than those from females in smaller, less dense social settings. Our results counter previous predictions and literature, showing that females breeding in large groups deposit more androgen in eggs, mechanistically, because they compete more with conspecifics and have higher circulating androgen levels themselves and, functionally, because it could be advantageous for their offspring to show high androgen-mediated competitive abilities early in life. Instead, because group size in this species is governed largely by site fidelity and the availability of old nests for re-use, and because reproductive output does not differ as a function of group size, it may be that competition is greater for limited nests in small groups, thus elevating androgen levels. Further, yolk androgens were previously shown to be affected by male quality, and the greater concentrations and amounts of yolk androgens in smaller sites may reflect differential allocation to darker males found at these sites. [source]

Hatching asynchrony and maternal androgens in egg yolks of House Wrens

JOURNAL OF AVIAN BIOLOGY, Issue 1 2001
Lisa A. Ellis
Synchronously and asynchronously hatching clutches of House Wrens Troglodytesaedon usually do not differ in reproductive success. Thus late-hatching nestlings in asynchronously hatching clutches somehow overcome any age- and size-related disadvantages of hatching after their nest-mates. One possible way for them to do this is for female House Wrens to add maternal androgens to the yolk of late-hatching eggs. We tested this hypothesis in a wild population of House Wrens that produces both asynchronously and synchronously hatching clutches. Yolks of eggs from both types of clutches were biopsied and the eggs returned to their nests to hatch. Radioimmunoassays revealed that total androgen levels in the yolk varied within and among clutches. However, total androgen levels in yolks did not vary predictably with egg position in either synchronously or asynchronously hatching clutches. Thus, deposition of androgens in yolk did not follow the expected pattern based on the potential for sibling competition in House Wrens. [source]

Relationship between urinary profile of the endogenous steroids and postmenopausal women with stress urinary incontinence

NEUROUROLOGY AND URODYNAMICS, Issue 3 2003
S.W. Bai
Abstract Aims The aims of this study were to investigate whether endogenous steroid hormones are (1) related to pathogenesis of stress urinary incontinence after menopause, (2) are related to severity of stress urinary incontinence, and (3) are related to prognostic parameters of stress urinary incontinence. Methods Twenty post-partum women with clinically diagnosed stress urinary incontinence and 20 age-matched postmenopausal women without stress urinary incontinence (control group) were evaluated. We compared urinary profile of the endogenous steroid hormones patients with stress urinary incontinence and controls, and between grade I and grade II of stress urinary incontinence. We also in vestigated the relationship between urinary profile of the endogenous steroid hormones and prognostic parameters of stress urinary incontinence (maximal urethral closure pressure, functional urethral length, Valsalva leak point pressure, cough leak point pressure, posterior urethrovesical angle, bladder neck descent, and stress urethral axis). The ages of the patients and those in the control group were 64.3,±,5.6 and 57.5,±,3.8 years old and the body mass indexes were 24.96,±,3.14 and 22.11,±, 2.73 kg/m2 in patients and in normal subjects, respectively. Nine patients were grade I and 11 were grade II. Estrone and 17,-estradiol only were detected in all subjects, regardless of control or patient group. It is noteworthy that there were no significant differ ences (P,>,0.05) in the levels of estrone and 17,-estradiol in the urine of postmenopausal normal subjects compared with in the urine of postmenopausal patients with urinary incontinence. E2/E1 ratio was not different between the two groups (P,>,0.05). Among the objective steroids, DHEA, ,4 -dione, ,5 -diol, Te, DHT, 16,-DHT, 11-keto An, THDOC, and THB were not detected either in the urine of normal subjects and nor in the urine of the patients. After comparing androgen levels between normal subjects and patients, no significant differences (P>0.05) were detected, except for 5,-THB and 5,-THF. Neither 5,-THB or 5,-THF were detected in the patients' urine. Et/An (11,-OH Et/11,-OH An) concentration ratios were not significantly different between the two groups, either (P,>,0.05). There were not significant differences of concentrations (,mol/g creatinine) of urinary steroids between grade I and grade II of stress urinary incontinence. Pregnanediol was significantly related to bladder neck descent in supine and sitting positions (R,=,0.79, P,=,0.01, and R,=,0.73, P,=,0.03, respectively), and pregnanetriol was significantly related to maximal urethral closure pressure and functional urethral length (R,=,0.68, P,=,0.04, and R,=,,0.79, P,=,0.01, respectively). Androsterone was significantly related to bladder neck descent in supine and sitting positions (R,=,0.68, P,=,0.04, and R,=,0.78, P,=,0.01, respectively). 5-AT was significantly related to bladder neck descent in sitting position and stress urethral axis (R,=,0.72, P,=,0.03, and R,=,,0.71, P,=,0.03). 11-Keto Et was significantly related to bladder neck descent in supine and sitting positions and related to stress ure thral axis (R,=,0.82, P,=,0.01, and R,=,0.81, P,=,0.01, R,=,,0.67, P,=,0.04, respectively). THS was signi ficantly related to bladder neck descent in supine and sitting positions and related to stress urethral axis (R,=,0.76, P,=,0.02, and R,=,0.74, P,=,0.02, R,=,,0.68, P,=,0.04, respectively). THE was significantly related to bladder neck descent in sitting position (R,=,0.67, P,=,0.04).,-Tetrahydrocortisol/,-tetrahydrocortisol (,-THF/,-THF) and ,-cortol were significantly related to maximal urethral closure pressure and functional urethral length (R,=,0.74, P,=,0.02, and R,=,,0.92, P,=,0.01; R,=,0.71, P,=,0.36, and R,=,,0.87, P,=,0.000, respectively). 17,-Estradiol (E2) was significantly related to bladder neck descent in supine position (R,=,,0.62, P,=,0.04) and 17,-estradiol/estrone (E2/E1) was significantly related to cough leak point pressure (R,=,0.79, P,=,0.01). In conclusion, the urinary concentrations of endogenous steroid metabolites in postmenopausal patients with stress urinary incontinence were not significantly different from normal patients and were not significantly different between grade I and grade II patients with stress urinary incontinence. Some endogenous steroid metabolites were positively or negatively significantly related to prognostic parameters of stress urinary incontinence. Neurourol. Urodynam. 22:198,205, 2003. © 2003 Wiley-Liss, Inc. [source]

Impact of diet and adiposity on circulating levels of sex hormone-binding globulin and androgens

NUTRITION REVIEWS, Issue 9 2008
Anne-Sophie Morisset
This review summarizes studies on the effect of various diets on circulating androgen levels and sex hormone-binding globulin (SHBG). Reduced caloric intake leading to significant weight loss increases SHBG levels regardless of diet composition, particularly in women. Cross-sectional studies show that dietary composition is generally not associated with SHBG levels independent of obesity level. No clear conclusion can be reached regarding the effect of various eating habits or dietary composition on circulating androgens. The evidence indicates that dietary effects on circulating SHBG, and possibly androgens, can be expected if body weight or fatness and/or insulin homeostasis are modulated. [source]

Immunohistochemical study of the relationship between Ki-67 labeling index of proliferating cells of gynecomastia, histological phase and duration of disease

PATHOLOGY INTERNATIONAL, Issue 11 2006
Seishi Kono
Gynecomastia is a benign proliferative lesion caused by various etiological factors and may result from a relative imbalance between serum estrogen and androgen levels. The histological alterations are similar, and gynecomastia can progress from a florid type to a fibrous type. The Ki-67 labeling index (LI) of gynecomastia specimen was investigated and higher Ki-67 LI was observed in florid and intermediate than in fibrous gynecomastia (P = 0.017). A correlation was found between the duration of disease and Ki-67 LI (P = 0.041): the shorter the duration the higher the Ki-67 LI. Thus, Ki-67 LI seems a useful tool to examine proliferation activity of gynecomastia and can assist in determination of appropriate treatment of gynecomastia with hormonal therapy. [source]

Androgens and energy allocation: Quasi-experimental evidence for effects of influenza vaccination on men's testosterone

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2009
Zachary L. Simmons
Androgens are proposed to allocate finite energetic resources away from immune function and toward anabolic processes related to reproductive effort. In situations of pathogen exposure, the significant energetic demands associated with mounting an immune response are expected to produce a decrease in androgen levels and commensurate redistribution of energy. We tested the hypothesis that even the mild immune challenge associated with vaccination may cause a decline in men's testosterone. As predicted, men who received an influenza vaccination exhibited a more negative change in testosterone over a 2-week period than did men in a nonequivalent control group who were not vaccinated. These results suggest that men's androgen concentrations may be finely calibrated to trade-offs between the energetic demands of immune responses and other life history problems. Am. J. Hum. Biol., 2009. © 2008 Wiley-Liss, Inc. [source]

Sex hormone-binding globulin and androgen levels in immigrant and British-born premenopausal British Pakistani women: Evidence of early life influences?

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 6 2006
Tessa M. Pollard
In women, raised insulin levels are associated with low sex hormone-binding globulin (SHBG) and high androgen levels, which are in turn linked to infertility. Since insulin resistance and hyperinsulinemia are major health problems for South Asians living in Western countries, we predicted that British Pakistani women would have low SHBG and raised androgen levels compared to European women. Given low birth weights in Pakistan, and known links between low birth weight and insulin resistance in later life, we also predicted that immigrant women born in Pakistan would have lower levels of SHBG and higher levels of androgens than British-born British Pakistani women. We assessed SHBG, testosterone, and the free androgen index (FAI) from a single serum sample taken on days 9,11 of the menstrual cycle from 20,40-year-old women living in the UK: 30 immigrants from Pakistan, 30 British-born British Pakistani women, and 25 British-born women of European origin. Age-adjusted analyses showed no significant differences in SHBG, testosterone, or FAI between British-born Pakistani and European-origin women. However, immigrant British Pakistani women had a significantly higher FAI than British-born British Pakistani women. Adjustment for body mass index, waist-to-hip ratio, and smoking status did not affect these results, but further adjustment for height, a marker of early environment, reduced the P -value for the difference in FAI between immigrant and British-born British Pakistani women to below significance. It is possible that the poorer early environment of immigrant British Pakistani women was at least partially responsible for their relatively high levels of free androgens. Am. J. Hum. Biol. 18:741,747, 2006. © 2006 Wiley-Liss, Inc. [source]

Hormonal Changes in Menopause and Implications on Sexual Health

THE JOURNAL OF SEXUAL MEDICINE, Issue 2007
Anneliese Schwenkhagen MD
ABSTRACT Introduction., The menopause is characterized by an array of changes to the female body caused by modulations which occur in the production of estrogens and androgens. The ovaries are important sites of testosterone production in the peri- and postmenopausal women, but the contribution of testosterone pro-hormones from the adrenal glands falls precipitously to the extent where the ovaries cannot correct the deficit. This results in a net decline in circulating testosterone levels. Aims., This paper gives an overview of this interesting subject area. Researchers have cogitated on the relationship between the physical effects of the menopause and the observed declines in testosterone levels, but it is now much clearer that falling testosterone levels cannot explain all of these changes. Main Outcome Measures., The cessation of follicular functioning results in a steep decline in the production of estrogens. This modulation is responsible for the physical manifestations of the menopause,hot flushes, sleep disturbances, mood changes, bleeding problems, local urogenital problems, vaginal changes, etc. Methods., A review of the pertinent literature was conducted to investigate hormonal changes around the menopause. A précis of the salient information is presented here. Results., Although the most obvious and well-known effects of the menopause are due to the decline of estrogen levels, the effects of falling testosterone levels are subtle, but by no means less significant. Reductions in sexual motivation, sexual arousal, vaginal lubrication, etc. are all associated with plummeting androgen levels. Conclusions., Today, several options exist for the treatment of the endocrinological changes associated with the menopause. Estrogen deficiency can be corrected with hormone replacement therapy and topical preparations for the genitalia. A new transdermal system for the administration of testosterone shows a great deal of potential for the treatment of androgen deficiency. Schwenkhagen A. Hormonal changes in menopause and implications on sexual health. J Sex Med 2007;4(suppl 3):220,226. [source]

ORIGINAL RESEARCH,WOMEN'S SEXUAL HEALTH: Comparison of Androgens in Women with Hypoactive Sexual Desire Disorder: Those on Combined Oral Contraceptives (COCs) vs.

THE JOURNAL OF SEXUAL MEDICINE, Issue 5 2006
Those not on COCs
ABSTRACT Introduction., Approximately one out of four sexually active women in the United States uses some form of hormonal contraceptive method because they provide the most effective reversible method of birth control available. However, little attention has been paid to possible adverse effects of combined oral contraceptives (COCs) on sexual functioning. Aims., The aim of this study was to examine the potential effects of COCs on women with hypoactive sexual desire disorder (HSDD). It was hypothesized that female patients with generalized, acquired HSDD on COCs have lower androgen levels than those not on COCs. Methods., The patients were healthy premenopausal women with HSDD, aged 22,50 years. Subjects had a history of adequate sexual desire, interest, and functioning. Participants were required to be in a stable, monogamous, heterosexual relationship and were screened for any medication or medical or psychiatric disorders that impact desire. The patients met operational criteria for global, acquired HSDD. The 106 patients were divided into two groups: those on COCs (N = 43) and those not on COCs (N = 63). A two-tailed t -test comparison was made between the two groups comparing free and total testosterone and sex hormone-binding globulin (SHBG). Main Outcome Measures., The main outcome measures are the differences between the two groups comparing free testosterone, total testosterone, and SHBG. Results., These patients with HSDD on COCs had significantly lower free and total testosterone levels compared with those who were not on COCs. The SHBG was significantly higher in the group on COCs compared with those who were not on COCs. Conclusion., The result of this study suggests that COCs in premenopausal women with HSDD are associated with lower androgen levels than those not on COCs. Further research is required to determine if low androgen levels secondary to COCs impact female sexual desire. Warnock JK, Clayton A, Croft H, Segraves R, and Biggs FC. Comparison of androgens in women with hypoactive sexual desire disorder: Those on combined oral contraceptives (COCs) vs. those not on COCs. J Sex Med 2006;3:878,882. [source]

Endocrine Aspects of Sexual Dysfunction in Men

THE JOURNAL OF SEXUAL MEDICINE, Issue 1 2004
Alvaro Morales MD
ABSTRACT Introduction., Endocrine disorders of sex steroid hormones may adversely affect men's sexual function. Aim., To provide expert opinions/recommendations concerning state-of-the-art knowledge for the pathophysiology, diagnosis and treatment of endocrinologic sexual medicine disorders. Methods., An International Consultation in collaboration with the major urology and sexual medicine associations assembled over 200 multidisciplinary experts from 60 countries into 17 committees. Committee members established specific objectives and scopes for various male and female sexual medicine topics. The recommendations concerning state-of-the-art knowledge in the respective sexual medicine topic represent the opinion of experts from five continents developed in a scientific and debate process. Concerning the Endocrine committee, there were eight experts from seven countries. Main Outcome Measure., Expert opinions/recommendations are based on grading of evidence-based medical literature, extensive internal committee discussion over 2 years, public presentation and deliberation. Results., Hypogonadism is a clinical and biochemical syndrome characterized by a deficiency in serum androgen levels which may decrease sexual interest, quality of erections and quality of life. Biochemical investigations include testosterone and either bioavailable or calculated free testosterone; prolactin should be considered when hypogonadism has been documented. If clinically indicated, androgen therapy should maintain testosterone within the physiological range avoiding supraphysiologic values. Digital rectal examination and determination of serum prostate specific antigen values are mandatory prior to therapy and regularly thereafter. Androgen therapy is usually long-term requiring regular follow-up, frequent monitoring of blood levels and beneficial and adverse therapeutic responses. Conclusions., Safe and effective treatments for endocrinologic sexual medicine disorders examined by prospective, placebo-controlled, multi-institutional clinical trials are needed. [source]

Serum prostate-specific antigen levels reflect the androgen milieu in patients with localized prostate cancer receiving androgen deprivation therapy: Tumor malignant potential and androgen milieu,,

THE PROSTATE, Issue 13 2010
Itsuhiro Takizawa
Abstract BACKGROUND Although androgen deprivation therapy (ADT) has a marked impact on the androgen milieu in vivo and outcomes of prostate cancer (PCa), it remains unclear which parameters reflect the androgen milieu during ADT or whether the milieu is associated with PCa aggressiveness. METHODS Seventy-two patients with localized PCa were prospectively studied based on their blood samples before and after ADT for 6 months. Serum androgens and related values were measured. RESULTS Before ADT, there was no correlation between the serum prostate-specific antigen (PSA) and androgen levels. After ADT, the serum PSA levels were correlated with each level of serum testosterone, dihydrotestosterone, androstenedione, dehydroepiandrosterone-sulfate (DHEA-S), and 3alpha-diol G (P,<,0.010 in all). Before ADT, patients with Gleason score of ,8 were likely to have lower serum testosterone levels than those with Gleason score of ,6 (P,=,0.058). After ADT, conversely, the testosterone levels in patients with Gleason score of ,8 appeared to be higher than in those with Gleason score of ,6 (P,=,0.060). The serum DHEA-S level was correlated with Gleason score before and after ADT (P,=,0.050 and P,=,0.040, respectively). CONCLUSIONS The serum PSA levels well reflect the androgen milieu in localized PCa patients receiving ADT, which can be explained by the Saturation Model and disease control. The androgen milieu in men with high Gleason score PCa is probably less affected by conventional ADT than that in men with low score cancer, which was suggested to be associated with adrenal androgen levels. Prostate 70: 1395,1401, 2010. © 2010 Wiley-Liss, Inc. [source]

The prostatic environment suppresses growth of androgen-independent prostate cancer xenografts: An effect influenced by testosterone

THE PROSTATE, Issue 11 2009
Karin Jennbacken
Abstract BACKGROUND Interactions between prostate cancer cells and their surrounding stroma play an important role in the growth and maintenance of prostate tumors. To elucidate this further, we investigated how growth of androgen-dependent (AD) LNCaP and androgen-independent (AI) LNCaP-19 prostate tumors was affected by different microenvironments and androgen levels. METHODS Tumor cells were implanted subcutaneously and orthotopically in intact and castrated immunodeficient mice. Orthotopic tumor growth was followed by magnetic resonance imaging (MRI). Gene expression in the tumors was evaluated by means of microarray analysis and microvessel density (MVD) was analyzed using immunohistochemistry. RESULTS The results showed that LNCaP-19 tumors grew more rapidly at the subcutaneous site than in the prostate, where tumors were obviously inhibited. Castration of the mice did not affect ectopic tumors but did result in increased tumor growth in the prostatic environment. This effect was reversed by testosterone treatment. In contrast to LNCaP-19, the LNCaP cells grew rapidly in the prostate and castration reduced tumor development. Gene expression analysis of LNCaP-19 tumors revealed an upregulation of genes, inhibiting tumor growth (including ADAMTS1, RGS2 and protocadherin 20) and a downregulation of genes, promoting cell adhesion and metastasis (including N-cadherin and NRCAM) in the slow-growing orthotopic tumors from intact mice. CONCLUSIONS The results show that the prostatic environment has a varying impact on AD and AI tumor xenografts. Data indicate that the androgen-stimulated prostatic environment limits growth of orthotopic AI tumors through induction of genes that inhibit tumor growth and suppression of genes that promote cell adhesion and metastasis. Prostate 69:1164,1175, 2009. © 2009 Wiley-Liss, Inc. [source]

Vascular endothelial growth factor and angiopoietin are required for prostate regeneration

THE PROSTATE, Issue 5 2007
Gui-min Wang
Abstract BACKGROUND The regulation of the prostate size by androgens may be partly the result of androgen effects on the prostatic vasculature. We examined the effect of changes in androgen levels on the expression of a variety of angiogenic factors in the mouse prostate and determined if vascular endothelial growth factor (VEGF)-A and the angiopoietins are involved in the vascular response to androgens. METHODS Expression of angiogenic factors in prostate was quantitated using real-time PCR at different times after castration and after administration of testosterone to castrated mice. Angiopoietins were localized in prostate by immunohistochemistry and in situ hybridization. The roles of VEGF and the angiopoietins in regeneration of the prostate were examined in mice inoculated with cells expressing soluble VEGF receptor-2 or soluble Tie-2. RESULTS Castration resulted in a decrease in VEGF-A, VEGF-B, VEGF-C, placenta growth factor, FGF-2, and FGF-8 expression after 1 day. In contrast, VEGF-D mRNA levels increased. No changes in angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), hepatocyte growth factor, VEGF receptor-1, VEGF receptor-2, or tie-2 mRNA levels were observed. Administration of testosterone to castrated mice had the opposite effect on expression of these angiogenic factors. Ang-2 was expressed predominately in prostate epithelial cells whereas Ang-1 was expressed in epithelium and smooth muscle. Inoculation of mice with cells expressing soluble VEGF receptor-2 or Tie-2 blocked the increase in vascular density normally observed after administration of testosterone to castrated mice. The soluble receptors also blocked the increase in prostate weight and proliferation of prostatic epithelial cells. CONCLUSION VEGF-A and angiopoietins are required for the vascular response to androgens and for the ability of the prostate to regenerate in response to androgens. Prostate 67: 485,499, 2007. © 2007 Wiley-Liss, Inc. [source]

YB-1 is upregulated during prostate cancer tumor progression and increases P-glycoprotein activity

THE PROSTATE, Issue 3 2004
Pepita Giménez-Bonafé
Abstract BACKGROUND Currently, the main obstacle to curing advanced prostate cancer is development of androgen independence (AI), where malignant cells acquire the ability to survive in the absence of androgens. Our initial experimental approach used cDNA microarrays to characterize changes in gene expression in the LNCaP human prostate tumor model during progression to AI. The transcription factor Y-box binding protein (YB-1) was shown to be one of the genes upregulated. We focused on increased YB-1 expression during progression in clinical specimens, and further examined one of its downstream targets, P-glycoprotein (P-gp). METHODS Northern blot analysis was performed on LNCaP tumor series, as well as immunohistochemical analyses of human prostate cancer tissue samples. YB-1 was transiently transfected and transport analysis were performed to analyze P-gp efflux activity. RESULTS YB-1 expression is markedly increased during benign to malignant transformation and further following androgen ablation. In addition, increased YB-1 expression after castration in the LNCaP model is linked to upregulation of P-gp. We demonstrate that YB-1 upregulates P-gp activity resulting in a 40% intracellular decrease in the P-gp substrate vinblastine. We have also found that P-gp increases the efflux of the endogenous androgen, dihydrotestosterone (DHT), from prostate cells and leads to decreased androgen regulated gene expression. CONCLUSIONS We hypothesize that early in prostate cancer progression, increased expression of YB-1 may increase P-gp activity which may in turn lower androgen levels in the prostate tumor cells. Suppression of androgen levels may activate cell survival pathways and lead to an adaptive survival advantage of androgen independent prostate cancer cells following androgen ablation therapy. © 2004 Wiley-Liss, Inc. [source]

An unusual case of vascular hypogonadism treated with clomiphene citrate and testosterone replacement

ANDROLOGIA, Issue 1 2009
R. S. Tan
Summary Many male patients are discovered on screening to suffer from hypogonadism and age related hypogonadism is being increasingly recognized. However, secondary causes of hypogonadism should not be overlooked, especially in patients who may have concomitant morbidity as highlighted in this case. Our patient with vascular hypogonadism was treated with testosterone and clomiphene citrate in cycles; with a hope of improving not only androgen levels but overall pituitary function as there were co-existing endocrine pathologies of albeit primary hypothyroidism and low IGF-1 levels. Treatment with exogenous testosterone is fairly well established; but there is also increasing evidence of the effectiveness and short-term safety of clomiphene citrate in restoring not only biological levels but functional states in males as well. As such, we report an unusual case of a patient seen at our Men's Health & Andrology clinic in which both the cause of some otherwise unremarkable symptoms and the treatment, using a combination of clomiphene citrate and testosterone, were remarkable. [source]

Anti,interleukin-6 receptor antibody therapy favors adrenal androgen secretion in patients with rheumatoid arthritis: A randomized, double-blind, placebo-controlled study

ARTHRITIS & RHEUMATISM, Issue 6 2006
Rainer H. Straub
Objective Proinflammatory cytokines such as tumor necrosis factor (TNF) were demonstrated to inhibit adrenal steroidogenesis in patients with rheumatoid arthritis (RA), and this was particularly evident in the increase in adrenal androgen levels during anti-TNF therapy. This study investigated the influence on steroidogenesis of an interleukin-6 (IL-6),neutralizing strategy using IL-6 receptor monoclonal antibodies (referred to as MRA). Methods In a placebo-controlled, double-blind, randomized study over 12 weeks in 29 patients with RA being treated with prednisolone, 13 of whom received placebo and 16 of whom received 8 mg MRA/kg body weight, the effects of MRA on serum levels of adrenocorticotropic hormone (ACTH), cortisol, 17-hydroxyprogesterone (17OHP), dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), androstenedione (ASD), estrone, and 17,-estradiol, as well as their respective molar ratios, were determined. Results MRA therapy markedly improved clinical signs of inflammation (the erythrocyte sedimentation rate, swollen joint score, and Disease Activity Score in 28 joints). Serum levels of ACTH and cortisol and the molar ratio of cortisol to ACTH did not change. Although serum levels of DHEA and DHEAS remained stable during therapy, the DHEAS:DHEA molar ratio significantly decreased in treated patients (P = 0.048). Serum levels of ASD as well as the ASD:cortisol and ASD:17OHP molar ratios increased in MRA-treated patients (minimum P < 0.004). Serum levels of estrone and 17,-estradiol did not change. but the estrone:ASD molar ratio (an indicator of aromatization) decreased during 12 weeks of MRA treatment (P = 0.001). Conclusion Neutralization of IL-6 increases secretion of biologically active adrenal androgens in relation to that of precursor hormones and estrogens. This is another important indication that proinflammatory cytokines interfere with adrenal androgen steroidogenesis in patients with RA. [source]

A novel testosterone gel formulation normalizes androgen levels in hypogonadal men, with improvements in body composition and sexual function

BJU INTERNATIONAL, Issue 4 2003
A.R.E. Blacklock, FRCS Ed
No abstract is available for this article. [source]

Androgenetic alopecia in children: report of 20 cases

BRITISH JOURNAL OF DERMATOLOGY, Issue 3 2005
A. Tosti
Summary Androgenetic alopecia (AGA) is the most common type of hair loss in adults. Although there are differences in the age at onset, the disease starts after puberty when enough testosterone is available to be transformed into dihydrotestosterone. We report 20 prepubertal children with AGA, 12 girls and eight boys, age range 6,10 years, observed over the last 4 years. All had normal physical development. Clinical examination showed hair loss with thinning and widening of the central parting of the scalp, both in boys and girls. In eight cases frontal accentuation and breach of frontal hairline were also present. The clinical diagnosis was confirmed by pull test, trichogram and dermoscopy in all cases, and by scalp biopsy performed in six cases. There was a strong family history of AGA in all patients. The onset of AGA is not expected to be seen in prepubertal patients without abnormal androgen levels. A common feature observed in our series of children with AGA was a strong genetic predisposition to the disease. Although the pathogenesis remains speculative, endocrine evaluation and a strict follow-up are strongly recommended. [source]

Adiponectin levels in adolescent girls with polycystic ovary syndrome (PCOS)

CLINICAL ENDOCRINOLOGY, Issue 6 2009
Orit Pinhas-Hamiel
Summary Objective, To determine serum adiponectin concentrations in adolescent girls with and without polycystic ovary syndrome (PCOS) and to assess possible correlations of adiponectin levels with insulin and androgen levels. Design, Prospective case,control study. Setting, Endocrine clinics in the community. Patients, Forty-four adolescent girls were grouped as follows: 14 were overweight [body mass index (BMI) standard deviation score >1·645] with PCOS; 16 were lean (BMI SDS <1·036) with PCOS; and 14 were lean (BMI SDS <1·036) without PCOS. Intervention, Blood samples were collected from all girls between 8 and 11 am, after an overnight fast. Main outcome measures, Serum levels of adiponectin, leptin, insulin, Müllerian-inhibiting substance, luteinizing hormone, follicle-stimulating hormone, testosterone, 17-alpha-hydroxyprogesterone, androstendione, dehydroepiandrosterone sulphate (DHEAS) and 17,-oestradiol. Results, Adiponectin concentrations were significantly decreased in obese adolescents with PCOS (10·5 ± 5·5 ,g/ml) compared with that in lean girls with or without PCOS (16·9 ± 8·64 and 18·0 ± 7·4 ,g/ml respectively). Leptin levels were significantly elevated in obese adolescents with PCOS compared with the levels in normal weight adolescents with PCOS, and compared with that in normal weight controls. Insulin levels were markedly higher in obese adolescents with PCOS compared with that in normal weight adolescents (12·3 ± 12·2 vs. 4·5 ± 2·9, P < 0·05), and compared with that in normal weight PCOS adolescents (7·4 ± 4·9); however, this difference was not statistically significant. Insulin levels did not differ between normal weight adolescents with PCOS and normal controls. Adiponectin concentrations correlated inversely with BMI, leptin and insulin. Conclusions, Hypoadiponectinaemia is evident only in obese adolescents with PCOS and therefore does not seem to be involved in the pathogenesis of PCOS in this age group. [source]

Activational effects of sex hormones on cognition in men

CLINICAL ENDOCRINOLOGY, Issue 5 2009
A. Ulubaev
Summary Background, Changing world demographic patterns, such as the increasing number of older people and the growing prevalence of cognitive impairment, present serious obstacles to preserving the quality of life and productivity of individuals. The severity of dementia varies from subclinical, mild cognitive impairment to neurodegenerative diseases such as Alzheimer's. In normally ageing men, these age-related cognitive declines are accompanied by gradual but marked decreases in androgen levels and changes in other hormone profiles. While developmental effects of sex hormones on cognition in the pre- and early postnatal period have been demonstrated, their activational effects in later life are still a focus of contemporary research. Although there is a plethora of published research on the topic, results have been inconsistent with different studies reporting positive, negative or no effects of sex hormones on various aspects of mental agility. Methods, This review summarizes the evidence supporting the biological plausibility of the activational effects of sex hormones upon cognition and describes the mechanisms of their actions. It offers a comprehensive summary of the studies of the effects of sex hormones on fluid intelligence in men utilizing elements from the Cochrane Collaboration Guidelines for Reviews. The results of both observational (cross-sectional and longitudinal) and interventional studies published to date are collated in table form and further discussed in the text. Factors contributing to the difficulties in understanding the effects of sex hormones on cognition are also examined. Conclusions, Although there is convincing evidence that steroid sex hormones play an organizational role in brain development in men, the evidence for activational effects of sex hormones affecting cognition in healthy men throughout adult life remains inconsistent. To address this issue, a new multifactorial approach is proposed which takes into account the status of other elements of the sex hormones axis including receptors, enzymes and other hormones. [source]