scholarly journals Changes in BMI modulate age-associated changes in sex hormone binding globulin and total testosterone, but not bioavailable testosterone in young adult men: the CARDIA Male Hormone Study

2006 ◽  
Vol 31 (4) ◽  
pp. 685-691 ◽  
Author(s):  
S M Gapstur ◽  
P Kopp ◽  
P H Gann ◽  
B C-H Chiu ◽  
L A Colangelo ◽  
...  
2007 ◽  
Vol 53 (12) ◽  
pp. 2160-2168 ◽  
Author(s):  
Frank Giton ◽  
Saïk Urien ◽  
Catherine Born ◽  
Jean Tichet ◽  
Jérôme Guéchot ◽  
...  

Abstract Background: Bioavailable testosterone (BT) is measured [assayed BT (aBT)] or calculated (cBT) in the diagnosis of hypogonadism in men. The cBT depends, however, on the values of the association constants of total testosterone (TT) for sex hormone–binding globulin (SHBG; Ks) and albumin (Ka), and its use therefore remains controversial. Methods: In 503 selected, untreated healthy men, 20–74 years old, we measured TT, dihydrotestosterone (DHT), and androstenediol (5-diol) by GC-MS, SHBG by RIA, and BT after ammonium sulfate precipitation or by calculation according to the law of mass action. Results: A slight decrease in TT, significant decreases in BT and 5-diol, no variation in DHT, and an increase in SHBG were observed with age. In young males (≤39 years), the lower normal limits were between 2.30 and 2.72 nmol/L for aBT and 8.50 nmol/L for TT. For Ks = 1 × 109 L/mol and Ka = 3.6 × 104 L/mol, the lower cBT limit was found to be 2-fold higher than for aBT. With optimized Ks = 1.9 × 109 L/mol and Ka = 2.45 × 104 L/mol, cBT values close to aBT were obtained. When 5-diol was included in the model as a competitive SHBG inhibitor, the correlation between cBT and aBT was better and the cBT:aBT ratios vs 5-diol were less biased. Conclusion: Lower normal serum aBT concentration in normal men appears to be between 2.30 and 2.72 nmol/L. Much higher serum cBT concentrations are associated with use of different association constants that may be inappropriate. When using the optimized binding constants, taking age-related 5-diol values into consideration slightly improves prediction of cBT.


Medicine ◽  
2019 ◽  
Vol 98 (20) ◽  
pp. e15628 ◽  
Author(s):  
Qingtao Yang ◽  
Zhenjie Li ◽  
Wencai Li ◽  
Liang Lu ◽  
Haoqiang Wu ◽  
...  

2021 ◽  
Vol 10 (16) ◽  
pp. 1140-1144
Author(s):  
Nandhini Logaprabhu ◽  
Sarmishta Murugesan

BACKGROUND We wanted to analyse the clinical profile of polycystic ovarian syndrome (PCOS) women with history, examination and ultrasonogram and correlate hirsutism with biochemical markers as free testosterone, dehydro-epiandrosterone sulphate (DHEAS), sex hormone binding globulin (SHBG), free testosterone, DHEAS, and SHBG. METHODS This study is a prospective observational study conducted from 2011 to 2013 in the Department of Obstetrics and Gynaecology, Shree Balaji Medical College and Hospital, Chrompet in patients attending Gynaecology OPD. 100 women visiting the OPD were taken as control and 100 women were taken for PCOS study. RESULTS Hyperandrogenism was studied and all the biochemical markers were significantly higher in polycystic ovarian syndrome patients than in controls (P < 0.0001). The highest AUC-ROC was found for bioavailable testosterone (0.852) followed by free androgen index (0.847) and free testosterone (0.837). Lower AUC-ROC was found for androstenedione, total testosterone and SHBG (0.706, 0.799 and 0.76, respectively). When free androgen index of 4.97 was taken as a cut off value, sensitivity was 71.4 % and specificity was 85.2 %. A cut off of 0.78 nmol / L for bioavailable testosterone had even higher sensitivity of 75.9 %, but slightly lower specificity of 83.3 %. Bioavailable testosterone and free androgen index correlated significantly (all P < 0.05) with DHEAS, LH / FSH ratio, androstenedione and total testosterone. In addition, bioavailable testosterone, free androgen index, and free testosterone correlated significantly with follicle count, ovarian volume, and hirsutism scores. CONCLUSIONS White women have about 20 % of excess of dehydro-epiandrosterone sulphate (DHEAS) and black women have 30 % excess of dehydro-epiandrosterone sulphate (DHEAS) in those having poly cystic ovaries patients. There is an age-associated decline in DHEAS levels which is similar in both control and poly cystic ovaries women, regardless of the race which was seen in this study. KEY WORDS Free Testosterone, Dehydro–Epiandrosterone Sulphate (DHEAS), Sex Hormone Binding Globulin (SHBG)


Author(s):  
Isabel Pimentel ◽  
Bingshu E Chen ◽  
Ana Elisa Lohmann ◽  
Marguerite Ennis ◽  
Jennifer Ligibel ◽  
...  

Abstract Background Metformin has been associated with lower breast cancer (BC) risk and improved outcomes in observational studies. Multiple biologic mechanisms have been proposed, including a recent report of altered sex hormones. We evaluated the effect of metformin on sex hormones in MA.32, a phase III trial of nondiabetic BC subjects who were randomly assigned to metformin or placebo. Methods We studied the subgroup of postmenopausal hormone receptor-negative BC subjects not receiving endocrine treatment who provided fasting blood at baseline and at 6 months after being randomly assigned. Sex hormone-binding globulin, bioavailable testosterone, and estradiol levels were assayed using electrochemiluminescence immunoassay. Change from baseline to 6 months between study arms was compared using Wilcoxon sum rank tests and regression models. Results 312 women were eligible (141 metformin vs 171 placebo); the majority of subjects in each arm had T1/2, N0, HER2-negative BC and had received (neo)adjuvant chemotherapy. Mean age was 58.1 (SD=6.9) vs 57.5 (SD=7.9) years, mean body mass index (BMI) was 27.3 (SD=5.5) vs 28.9 (SD=6.4) kg/m2 for metformin vs placebo, respectively. Median estradiol decreased between baseline and 6 months on metformin vs placebo (−5.7 vs 0 pmol/L; P &lt; .001) in univariable analysis and after controlling for baseline BMI and BMI change (P &lt; .001). There was no change in sex hormone-binding globulin or bioavailable testosterone. Conclusion Metformin lowered estradiol levels, independent of BMI. This observation suggests a new metformin effect that has potential relevance to estrogen sensitive cancers.


2010 ◽  
Vol 162 (4) ◽  
pp. 747-754 ◽  
Author(s):  
Torkel Vikan ◽  
Henrik Schirmer ◽  
Inger Njølstad ◽  
Johan Svartberg

ObjectiveTo study the impact of endogenous sex hormone levels in community-dwelling men on later risk for type 2 diabetes.DesignPopulation-based prospective cohort study.MethodsFor the analyses, 1454 men who participated in the fourth Tromsø study (1994–1995) were used. Cases of diabetes were retrieved and validated until 31.12.05 following a detailed protocol. The prospective association between sex hormones and diabetes was examined using Cox proportional hazard regression analysis, allowing for multivariate adjustments.ResultsThere was a significantly lowered multi-adjusted risk for later diabetes with higher normal total testosterone levels, both linearly per s.d. increase (hazard ratio (HR) 0.71, confidence interval (CI) 0.54–0.92) and in the higher quartiles of total testosterone than in the lowest quartiles (HR 0.53, CI 0.33–0.84). A reduced multi-adjusted risk for incident diabetes was also found for men with higher sex hormone-binding globulin (SHBG) levels, both linearly per s.d. increase (HR 0.55, CI 0.39–0.79) and when comparing the third (HR 0.38, CI 0.18–0.81) and the fourth quartile (HR 0.37, CI 0.17–0.82) to the lowest quartile. The associations with total testosterone and SHBG were no longer significant after inclusion of waist circumference to the multivariate models. Estradiol (E2) was positively associated with incident diabetes after multivariate adjustments including waist circumference when comparing the second (HR 0.49, CI 0.26–0.93) and the third (HR 0.51, CI 0.27–0.96) quartile to the highest quartile.ConclusionMen with higher E2 levels had an increased risk of later diabetes independent of obesity, while men with lower total testosterone and SHBG had an increased risk of diabetes that appeared to be dependent on obesity.


1990 ◽  
Vol 64 (1) ◽  
pp. 111-119 ◽  
Author(s):  
Timothy J. A. Key ◽  
Liane Roe ◽  
Margaret Thorogood ◽  
John W. Moore ◽  
Graham M. G. Clark ◽  
...  

Total testosterone (T), total oestradiol (E2) and sex hormone-binding globulin (SHBG) concentrations were measured in plasma samples from fifty-one male vegans and fifty-seven omnivores of similar age. Free T concentration was estimated by calculation, in comparison with the omnivores, the vegans had 7% higher total T (P = 0.250), 23% higher SHBG (P = 0.001), 3% lower free T (P = 0.580), and 11% higher E2 (P = 0.194). In a subset of eighteen vegans and twenty-two omnivores for whom 4 d diet records were available, there were statistically significant correlations between T and polyunsaturated fatty acids (r 0.37), SHBG and fat (r 0.43 for total fat, 0.46 for saturated fatty acids and 0.33 for polyunsaturated fatty acids), and SHBG and alcohol (r–0.39). It is concluded that a vegan diet causes a substantial increase in SHBG but has little effect on total or free T or on E2.


1986 ◽  
Vol 113 (3) ◽  
pp. 457-462 ◽  
Author(s):  
Ragnar Tegelman ◽  
Pia Lindeskog ◽  
Kjell Carlström ◽  
Åke Pousette ◽  
Rolf Blomstrand

Abstract. The effect of one week of controlled fasting (3 1 of fluid containing 50 g of carbohydrate/day) upon the serum levels of hormones, sex hormone binding globulin, and albumin was studied in healthy subjects. Fasting caused decreased levels of prolactin and T3, no changes in the levels of TSH, FSH, LH, dehydroepiandrosterone, 4-androstene-3,17-dione, total oestrone, and total testosterone, and increased levels of cortisol, dehydroepiandrosterone sulphate and albumin. A significant positive correlation was found between albumin and dehydroepiandrosterone sulphate. Fasting rapidly increased the levels of sex hormone binding globulin and decreased the percentage of free testosterone and the calculated free testosterone level in both sexes. A decreased metabolic clearance of certain steroids (cortisol, dehydroepiandrosterone sulphate) owing to an increased protein binding may be one of the endocrine consequences of fasting. An increased protein binding of testosterone may be outweighed by a decreased gonadal production, thus resulting in an unchanged total testosterone level. The increased sex hormone binding globulin level could not be explained by changes in gonadal and thyroid hormones.


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