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Changes in Men’s Salivary Testosterone and Cortisol Levels, and in Sexual Desire after Smelling Female Axillary and Vulvar Scents  [PDF]
Ana Lilia Cerda-Molina,Leonor Hernández-López,Claudio E. de la O,Ricardo Mondragón-Ceballos
Frontiers in Endocrinology , 2013, DOI: 10.3389/fendo.2013.00159
Abstract: Several studies have shown that a woman’s vaginal or axillary odors convey information on her attractivity. Yet, whether such scents induce psychoneuroendocrinological changes in perceivers is still controversial. We studied if smelling axillary and vulvar odors collected in the periovulatory and late luteal phases of young women modify salivary testosterone and cortisol levels, as well as sexual desire in men. Forty-five women and 115 men, all of them college students and unacquainted with each other, participated in the study. Female odors were collected on pads affixed to the axilla and on panty protectors both worn the entire night before experiments. Men provided five saliva samples, a basal one before the smelling procedure, and four more 15, 30, 60, and 75 min after exposure to odors. Immediately after smelling the odor source, men answered a questionnaire rating hedonic qualities of scents, and after providing the last saliva sample they answered questionnaire on sexual desire. We found that periovulatory axillary and vulvar odors increased testosterone and cortisol levels, with vulvar scents producing a more prolonged effect. Luteal axilla odors decreased testosterone and cortisol levels, while luteal vulva odors increased cortisol. Periovulatory axilla and vulva scents accounted for a general increase of interest in sex. These odors were also rated as more pleasant and familiar, while luteal vulvar odors were perceived as intense and unpleasant.
Associations of sex hormone-binding globulin and testosterone with diabetes among men and women (the Saku Diabetes study): a case control study
Atsushi Goto, Akemi Morita, Maki Goto, Satoshi Sasaki, Motohiko Miyachi, Naomi Aiba, Yasuo Terauchi, Mitsuhiko Noda, Shaw Watanabe, the Saku Cohort Study Group
Cardiovascular Diabetology , 2012, DOI: 10.1186/1475-2840-11-130
Abstract: We conducted a case–control study that included 300 diabetes cases (215 men and 85 women) and 300 matched controls from the Saku cohort study. Diabetes was defined by either fasting plasma glucose levels ≥126 mg/dL, 2-h post-load glucose levels ≥200 mg/dL after a 75 g oral glucose tolerance test, or diabetes diagnosed by physicians. We fitted conditional logistic regression models to examine the associations between SHBG and total testosterone levels with diabetes by sex. To evaluate the impact of fatty liver, we used the fatty liver index (FLI), a validated measure derived from serum triglyceride levels, body mass index (BMI), waist circumference, and γ-glutamyltransferase levels.After adjusting for age, family history of diabetes, smoking, physical activity, BMI, and FLI, SHBG levels were inversely associated with diabetes among women (odds ratio [OR] comparing the highest with the lowest quartiles, 0.13 [95% confidence interval {CI}, 0.02–0.96]), but not among men. Similar patterns were observed in a subgroup analysis restricted to postmenopausal women"(OR, 0.12 [95% CI, 0.01–1.17]). In contrast, testosterone levels were inversely associated with diabetes among men (OR, 0.45 [95% CI, 0.23–0.89]), but not among women.Our findings suggest that SHBG in women and testosterone in men may be inversely associated with diabetes.Emerging data indicate that sex hormone-binding globulin (SHBG) as well as adipose tissue function may play important roles in the development of type 2 diabetes [1-3] and cardiovascular diseases [4,5]. SHBG is synthesized primarily in the liver and binds to androgens and estrogens, thereby regulating the biologically active fraction of sex hormones [6]. Thus, the circulating SHBG level is a major determinant of the metabolic clearance of sex hormones, modulating the access of such sex hormones to their target tissues. The plasma membranes of various kinds of cells have been recently shown to be capable of binding specifically and with a high affi
Testosterone, Sex Hormone-Binding Globulin and the Metabolic Syndrome in Men: An Individual Participant Data Meta-Analysis of Observational Studies  [PDF]
Judith S. Brand, Maroeska M. Rovers, Bu B. Yeap, Harald J. Schneider, Tomi-Pekka Tuomainen, Robin Haring, Giovanni Corona, Altan Onat, Marcello Maggio, Claude Bouchard, Peter C. Y. Tong, Richard Y. T. Chen, Masahiro Akishita, Jourik A. Gietema, Marie-Hélène Gannagé-Yared, Anna-Lena Undén, Aarno Hautanen, Nicolai P. Goncharov, Philip Kumanov, S. A. Paul Chubb, Osvaldo P. Almeida, Hans-Ulrich Wittchen, Jens Klotsche, Henri Wallaschofski, Henry V?lzke, Jussi Kauhanen, Jukka T. Salonen, Luigi Ferrucci, Yvonne T. van der Schouw
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0100409
Abstract: Background Low total testosterone (TT) and sex hormone-binding globulin (SHBG) concentrations have been associated with the metabolic syndrome (MetS) in men, but the reported strength of association varies considerably. Objectives We aimed to investigate whether associations differ across specific subgroups (according to age and body mass index (BMI)) and individual MetS components. Data sources Two previously published meta-analyses including an updated systematic search in PubMed and EMBASE. Study Eligibility Criteria Cross-sectional or prospective observational studies with data on TT and/or SHBG concentrations in combination with MetS in men. Methods We conducted an individual participant data meta-analysis of 20 observational studies. Mixed effects models were used to assess cross-sectional and prospective associations of TT, SHBG and free testosterone (FT) with MetS and its individual components. Multivariable adjusted odds ratios (ORs) and hazard ratios (HRs) were calculated and effect modification by age and BMI was studied. Results Men with low concentrations of TT, SHBG or FT were more likely to have prevalent MetS (ORs per quartile decrease were 1.69 (95% CI 1.60-1.77), 1.73 (95% CI 1.62-1.85) and 1.46 (95% CI 1.36-1.57) for TT, SHBG and FT, respectively) and incident MetS (HRs per quartile decrease were 1.25 (95% CI 1.16-1.36), 1.44 (95% 1.30-1.60) and 1.14 (95% 1.01-1.28) for TT, SHBG and FT, respectively). Overall, the magnitude of associations was largest in non-overweight men and varied across individual components: stronger associations were observed with hypertriglyceridemia, abdominal obesity and hyperglycaemia and associations were weakest for hypertension. Conclusions Associations of testosterone and SHBG with MetS vary according to BMI and individual MetS components. These findings provide further insights into the pathophysiological mechanisms linking low testosterone and SHBG concentrations to cardiometabolic risk.
Sexual Orientation, Drug Use Preference during Sex, and HIV Risk Practices and Preferences among Men Who Specifically Seek Unprotected Sex Partners via the Internet  [PDF]
Hugh Klein
International Journal of Environmental Research and Public Health , 2009, DOI: 10.3390/ijerph6051620
Abstract: The present study entailed conducting a content analysis of 1,434 ads/profiles posted on one of the most popular “Men who have Sex with Men” (MSM) websites that specifically fosters unprotected sex. Ads/profiles were selected randomly based on the American ZIP code of residence (n = 1,316), with a randomly-drawn oversampling of profiles of men who self-identified as heterosexual or “curious” rather than gay or bisexual (n = 118). Data were collected between September 2006 and September 2007. The purpose of the present paper is to examine the conjoint effects of self-identified sexual orientation and preference for having/not having sex while high, on men’s sought-after sexual risk. Analytical comparisons of the four groups showed that, on most measures, the combination of sexual orientation and drug use preference during sex differentiated the men. Generally speaking, gay/bisexual men who advertised online for partners with whom they could have sex while high expressed the greatest interest in risky sexual behaviors (e.g., felching, unprotected oral sex, unprotected anal sex) and various risk-related preferences (e.g., multiple partner sex, anonymous sex, eroticizing ejaculatory fluids). This is especially true when they are compared to their heterosexual/“curious” counterparts whose online profiles were not as likely to indicate a desire for having sex while high.
Salivary testosterone levels in preadolescent children
Daniela Ostatníková, Karol Pastor, Zdenek Putz, Monika Dohnányiová, Anna Mat'a?eje, Richard Hampl
BMC Pediatrics , 2002, DOI: 10.1186/1471-2431-2-5
Abstract: Testosterone levels were determined in 203 healthy preadolescent children (77 girls and 126 boys) from saliva samples by radioimmunoassay. Sampling was performed once a year with respect to circadian and seasonal fluctuations of testosterone. Data were statistically analyzed by Statgraphic software.Mean salivary testosterone concentrations (± SD) were 0.038 ± 0.012 nmol/L and 0.046 ± 0.026 nmol/L for girls and boys, with the medians 0.035 nmol/L and 0.041 nmol/L, respectively. Statistical analysis did not prove changes in salivary testosterone concentrations in the preadolescent period of life, with an exception of the insignificant fall at the age of 7 years, and an insignificant rise at the age of 9 years in girls.Generally it can be concluded that salivary testosterone levels in our prepubertal subjects remained stable. There was no significant increase of salivary testosterone levels from the age of 6 until the age of 9 in both sexes. Sexual dimorphism in salivary testosterone levels was proved with significantly higher (p = 0.009) salivary testosterone levels in boys than in girls.Saliva sampling is advantageous to the patient, especially in children since it is a non-invasive, stress-free technique and enables multiple sampling. The primary entry of the steroid hormones as testosterone into saliva is via passive diffusion through the salivary gland epithelium. The concentration of the free hormone in plasma provides concentration gradient that drives diffusion of the steroid through the epithelial membrane into the primary secretory fluid within the acinar intercalated duct complex [1]. This holds true even under conditions of altered saliva flow rate, which may be reduced e.g. by anticholinergic medication [2] and increased by citric acid stimulation [3]. Thus, the concentration of unconjugated steroids in saliva does not depend on the rate of saliva production [4]. Testosterone concentration in saliva though differing slightly from the concentration of unbou
Genetic Determinants of Serum Testosterone Concentrations in Men  [PDF]
Claes Ohlsson equal contributor ,Henri Wallaschofski equal contributor,Kathryn L. Lunetta equal contributor,Lisette Stolk equal contributor,John R. B. Perry equal contributor,Annemarie Koster equal contributor,Ann-Kristin Petersen equal contributor,Joel Eriksson equal contributor,Terho Lehtim?ki equal contributor,Ilpo T. Huhtaniemi equal contributor,Geoffrey L. Hammond equal contributor,Marcello Maggio,Andrea D. Coviello,EMAS Study Group,Luigi Ferrucci,Margit Heier,Albert Hofman,Kate L. Holliday,John-Olov Jansson,Mika K?h?nen,David Karasik,Magnus K. Karlsson,Douglas P. Kiel,Yongmei Liu,?sten Ljunggren,Mattias Lorentzon,Leo-Pekka Lyytik?inen,Thomas Meitinger,Dan Mellstr?m,David Melzer,Iva Miljkovic,Matthias Nauck,Maria Nilsson,Brenda Penninx,Stephen R. Pye,Ramachandran S. Vasan,Martin Reincke,Fernando Rivadeneira,Abdelouahid Tajar,Alexander Teumer,André G. Uitterlinden,Jagadish Ulloor,Jorma Viikari,Uwe V?lker,Henry V?lzke,H. Erich Wichmann,Tsung-Sheng Wu,Wei Vivian Zhuang,Elad Ziv,Frederick C. W. Wu ?,Olli Raitakari ?,Anna Eriksson ?,Martin Bidlingmaier ?,Tamara B. Harris ?,Anna Murray ?,Frank H. de Jong ?,Joanne M. Murabito ?,Shalender Bhasin ?,Liesbeth Vandenput ?,Robin Haring ?
PLOS Genetics , 2011, DOI: 10.1371/journal.pgen.1002313
Abstract: Testosterone concentrations in men are associated with cardiovascular morbidity, osteoporosis, and mortality and are affected by age, smoking, and obesity. Because of serum testosterone's high heritability, we performed a meta-analysis of genome-wide association data in 8,938 men from seven cohorts and followed up the genome-wide significant findings in one in silico (n = 871) and two de novo replication cohorts (n = 4,620) to identify genetic loci significantly associated with serum testosterone concentration in men. All these loci were also associated with low serum testosterone concentration defined as <300 ng/dl. Two single-nucleotide polymorphisms at the sex hormone-binding globulin (SHBG) locus (17p13-p12) were identified as independently associated with serum testosterone concentration (rs12150660, p = 1.2×10?41 and rs6258, p = 2.3×10?22). Subjects with ≥3 risk alleles of these variants had 6.5-fold higher risk of having low serum testosterone than subjects with no risk allele. The rs5934505 polymorphism near FAM9B on the X chromosome was also associated with testosterone concentrations (p = 5.6×10?16). The rs6258 polymorphism in exon 4 of SHBG affected SHBG's affinity for binding testosterone and the measured free testosterone fraction (p<0.01). Genetic variants in the SHBG locus and on the X chromosome are associated with a substantial variation in testosterone concentrations and increased risk of low testosterone. rs6258 is the first reported SHBG polymorphism, which affects testosterone binding to SHBG and the free testosterone fraction and could therefore influence the calculation of free testosterone using law-of-mass-action equation.
Low salivary testosterone levels in patients with breast cancer
Constantine Dimitrakakis, David Zava, Spyros Marinopoulos, Alexandra Tsigginou, Aris Antsaklis, Rebecca Glaser
BMC Cancer , 2010, DOI: 10.1186/1471-2407-10-547
Abstract: Salivary hormone levels of testosterone (T), Estradiol (E2), Progesterone (P), Estriol (E3), Estrone (E1), DHEAS and Cortisol (C) were measured by Enzyme Immunoassay (EIA) in 357 women with histologically verified breast cancer and 184 age-matched control women.Salivary T and DHEAS levels were significantly lower in breast cancer cases vs. controls (27.2+13.9 vs. 32.2+17.5 pg/ml, p < 0.001 for T and 5.3+4.3 vs. 6.4+4.5 ng/ml, p = 0.007 for DHEAS). E2 and E1 levels were elevated and E3 levels were lowered in cases vs. controls.Salivary T levels, representing the bioavailable hormone, are significantly lower in women with breast cancer compared to age-matched control women. These findings support the protective role of biovailable testosterone in counteracting the proliferative effects of estrogens on mammary tissue.The risk of developing breast cancer is related to events of reproductive life and lifestyle factors that modify levels of endogenous sex hormones. Soon after the discovery of sex hormones, it was suggested that breast cancer risk was related to endogenous estrogen levels. Recent large prospective cohort studies on postmenopausal women make it clear that high levels of estrogens increase mammary gland proliferation and are associated with increased breast cancer risk [1].Interestingly, several observations suggest that androgens may counteract the proliferative effects of estrogen and progestogen in the mammary gland. In cell cultures and animal experiments, androgens have been shown to exert anti-proliferative effects [2]. It has also been demonstrated that a negative association exists between breast cell proliferation and levels of free testosterone in both pre- and postmenopausal women [3,4]. However, the relationship between endogenous androgen levels (testosterone, androstenedione, dehydroepiandrosterone (DHEA)) and breast cancer risk is still unclear with both epidemiologic and experimental data providing conflicting results [5,6]. Many of these stu
Statin Therapy and Serum Testosterone in Men with Type 2 Diabetes
Mohammed Fakhraldeen*, Huseen Saad Mostafa
Egyptian Journal of Hospital Medicine , 2010,
Abstract: There is a high prevalence of hypogonadism in men with type 2 diabetes. Statins could potentially decrease testosterone levels by reducing the availability of cholesterol for androgen synthesis. In this study we compared testosterone levels and hypogonadal symptoms with statin use in men with type 2 diabetes. PATIENTS AND METHODS Total testosterone, sex hormone-binding globulin (SHBG), and estradiol were measured by an enzyme-linked immunosorbent assay. Bioavailable testosterone was measured by the modified ammonium sulfate precipitation method. Free testosterone was calculated using Vermeulen's formula. Symptoms of hypogonadism were assessed using the Androgen Deficiency in the Aging Male questionnaire. RESULTS Statins were associated with lower total testosterone and a trend toward lower SHBG compared with untreated patients. Bioavailable testosterone, free testosterone, estradiol, and hypogonadal symptoms were not affected. Atorvastatin was associated with reduced total testosterone and a trend toward reduced SHBG compared with no treatment, and there was a dose-response effect with the lowest levels of total testosterone seen in men treated with 20 mg atorvastatin .Simvastatin use was not associated with significant reductions in testosterone or SHBG levels. CONCLUSION Assessing androgen status using total testosterone in men with type 2 diabetes treated with statins, particularly atorvastatin, may potentially lead to diagnostic error. Levels of bioavailable testosterone or free testosterone are recommended for the assessment of hypogonadism in this group if total testosterone levels are borderline.
The role of testosterone in type 2 diabetes and metabolic syndrome in men
Saad, Farid;
Arquivos Brasileiros de Endocrinologia & Metabologia , 2009, DOI: 10.1590/S0004-27302009000800002
Abstract: over the last three decades, it has become apparent that testosterone plays a significant role in glucose homeostasis and lipid metabolism. the metabolic syndrome is a clustering of risk factors predisposing to diabetes mellitus type 2, atherosclerosis and cardiovascular morbidity and mortality. the main components of the syndrome are visceral obesity, insulin resistance, glucose intolerance, raised blood pressure and dyslipidemia (elevated triglycerides, low levels of high-density lipoprotein cholesterol), and a pro-inflammatory and thrombogenic state. cross-sectional epidemiological studies have reported a direct correlation between plasma testosterone and insulin sensitivity, and low testosterone levels are associated with an increased risk of type 2 diabetes mellitus, dramatically illustrated by androgen deprivation in men with prostate carcinoma. lower total testosterone and sex hormone-binding globulin (shbg) predict a higher incidence of the metabolic syndrome. there is evidence that hypotestosteronemia should be an element in the definition of the metabolic syndrome since low levels of testosterone are associated with or predict the development of the metabolic syndrome and of diabetes mellitus. administration of testosterone to hypogonadal men reverses part of the unfavorable risk profile for the development of diabetes and atherosclerosis. so far, studies on the effects of normalization of testosterone in hypogonadal men on glucose homeostasis are limited, but convincing, and if diabetes mellitus is viewed in the context of the metabolic syndrome, the present results of testosterone treatment are very encouraging.
Testosterone replacement therapy for older men  [cached]
Stephen E Borst,Thomas Mulligan
Clinical Interventions in Aging , 2007,
Abstract: Stephen E Borst, Thomas MulliganGeriatrics Research, Education, and Clinical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USAAbstract: Despite intensive research on testosterone therapy for older men, important questions remain unanswered. The evidence clearly indicates that many older men display a partial androgen deficiency. In older men, low circulating testosterone is correlated with low muscle strength, with high adiposity, with insulin resistance and with poor cognitive performance. Testosterone replacement in older men has produced benefits, but not consistently so. The inconsistency may arise from differences in the dose and duration of testosterone treatment, as well as selection of the target population. Generally, studies reporting anabolic responses to testosterone have employed higher doses of testosterone for longer treatment periods and have targeted older men whose baseline circulating bioavailable testosterone levels were low. Most studies of testosterone replacement have reported anabolic that are modest compared to what can be achieved with resistance exercise training. However, several strategies currently under evaluation have the potential to produce greater anabolic effects and to do so in a safe manner. At this time, testosterone therapy can not be recommended for the general population of older men. Older men who are hypogonadal are at greater risk for the catabolic effects associated with a number of acute and chronic medical conditions. Future research is likely to reveal benefits of testosterone therapy for some of these special populations. Testosterone therapy produces a number of adverse effects, including worsening of sleep apnea, gynecomastia, polycythemia and elevation of PSA. Efficacy and adverse effects should be assessed frequently throughout the course of therapy.Keywords: aging, testosterone, hypogonadism, physical function
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