| 1. |
- Antonio, Leen, et al.
(författare)
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Associations Between Sex Steroids and the Development of Metabolic Syndrome: A Longitudinal Study in European Men
- 2015
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 100:4, s. 1396-1404
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Tidskriftsartikel (refereegranskat)abstract
- Context: Low testosterone (T) has been associated with incident metabolic syndrome (MetS), but it remains unclear if this association is independent of sex hormone binding globulin (SHBG). Estradiol (E2) may also be associated with MetS, but few studies have investigated this. Objective: To study the association between baseline sex steroids and the development of incident MetS and to investigate the influence of SHBG, body mass index (BMI) and insulin resistance on this risk. Methods: Three thousand three hundred sixty nine community-dwelling men aged 40-79 years were recruited for participation in EMAS. MetS was defined by the updated NCEP ATP III criteria. Testosterone and E2 levels were measured by liquid and gas chromatography/mass spectrometry, respectively. Logistic regression was used to assess the association between sex steroids and incident MetS. Results: One thousand six hundred fifty one men without MetS at baseline were identified. During follow-up, 289 men developed incident MetS, while 1362 men did not develop MetS. Men with lower baseline total T levels were at higher risk for developing MetS [odds ratio (OR) = 1.72, P < .001), even after adjustment for SHBG (OR = 1.43, P < .001), BMI (OR = 1.44, P < .001) or homeostasis model assessment of insulin resistance (HOMA-IR) (OR = 1.64, P < .001). E2 was not associated with development of MetS (OR = 1.04; P = .56). However, a lower E2/T ratio was associated with a lower risk of incident MetS (OR = 0.38; P < .001), even after adjustment for SHBG (OR = 0.48; P < .001), BMI (OR = 0.60; P = .001) or HOMA-IR (OR = 0.41; P < .001). Conclusions: Inmen, lower Tlevels, but not E2, are linked with an increased risk of developing MetS, independent of SHBG, BMI or insulin resistance. A lower E2/T ratio may be protective against developing MetS.
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| 2. |
- Antonio, Leen, et al.
(författare)
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Low Free Testosterone is Associated with Hypogonadal Signs and Symptoms in Men with Normal Total Testosterone.
- 2016
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 101:7, s. 2647-2657
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Tidskriftsartikel (refereegranskat)abstract
- During ageing, total testosterone (TT) declines and SHBG increases, resulting in a greater decrease in calculated free testosterone (cFT). Currently, guidelines suggest using TT to diagnose androgen deficiency and to reserve cFT only for men with borderline TT.
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| 3. |
- Aschim, Elin L, et al.
(författare)
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The RsaI polymorphism in the ER{beta} gene is associated with male infertility.
- 2005
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 90:Jul 5, s. 5343-5348
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Tidskriftsartikel (refereegranskat)abstract
- Context: Hypospadias, cryptorchidism, testicular cancer, and low semen quality have been proposed as being parts of the testicular dysgenesis syndrome (TDS) hypothetically due to changes in the androgen- estrogen balance in utero. Estrogens and estrogen receptors (ERs) play a role in regulating testicular function. ER beta contains two silent polymorphisms, RsaI (G1082A) and AluI (G1730A). Objective: We investigated the significance of these polymorphisms in the etiology of disorders being part of TDS. Setting: The patients were recruited consecutively through university hospital clinics. Participants: Four groups of Caucasian patients were included: 106 men from infertile couples with a sperm concentration less than 5 x 106 spermatozoa/ ml, 86 testicular cancer patients, 51 boys with hypospadias, and 23 cases with cryptorchidism. Military conscripts (n = 186) with sperm concentration higher than 5 x 10(6) spermatozoa/ ml served as controls. Main Outcome Measures: ER beta polymorphisms RsaI and AluI were determined by allele-specific PCR. In addition, reproductive hormone analyses were performed in controls and infertile men. Results: Compared with the controls, the frequency of the heterozygous RsaI AG-genotype was three times higher in infertile men (13.2 vs. 4.3%; P = 0.01). The heterozygous RsaI AG-genotype was associated with an approximately 20% reduction in LH concentration, compared with the wild-type RsaI GG genotype in both controls and infertile men. Subjects with testicular cancer, hypospadias, or cryptorchidism did not differ from controls regarding the frequency of any of the polymorphisms. Conclusions: Polymorphisms in ER beta may have modulating effects on human spermatogenesis. The phenotype of TDS seems to be, at least partly, determined by the genotype.
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| 4. |
- Aschim, EL, et al.
(författare)
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Linkage between cryptorchidism, hypospadias, and GGN repeat length in the androgen receptor gene
- 2004
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 89:10, s. 5105-5109
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Tidskriftsartikel (refereegranskat)abstract
- Although sufficient androgen receptor (AR) function is crucial for normal male sexual differentiation, single-point mutations in the AR gene are infrequent in the two most common male congenital malformations, hypospadias and cryptorchidism. Because polymorphic CAG and GGN segments regulate AR function, we investigated whether there was any association between these polymorphisms and mentioned malformations. Genotyping was performed by direct sequencing of DNA from patients diagnosed with hypospadias (n = 51) and cryptorchidism ( n = 23) and controls ( n = 210). The subjects with hypospadias were divided into subgroups of glanular, penile, and penoscrotal hypospadias. Median GGN lengths were significantly higher ( 24 vs. 23) among both subjects with cryptorchidism, compared with controls ( P = 0.001), and those with penile hypospadias, compared with either controls ( P = 0.003) or glanular and penoscrotal hypospadias combined ( P = 0.018). The frequency of cases with GGN 24 or more vs. GGN = 23, differed significantly among those with cryptorchidism (65/35%), compared with controls (31/54%) ( P = 0.012), and among subjects with penile hypospadias (69/31%), compared with either controls ( P = 0.035) or glanular or penoscrotal hypospadias combined (32/55%) ( P = 0.056). There were no significant differences in CAG lengths between the cases and controls. Our findings indicate an association between GGN length and the risk of cryptorchidism and penile hypospadias, both conditions considered consequences of low androgenicity.
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| 5. |
- Huhtaniemi, Ilpo T, et al.
(författare)
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Effect of Polymorphisms in Selected Genes Involved in Pituitary-Testicular Function on Reproductive Hormones and Phenotype in Aging Men.
- 2010
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 95, s. 1898-1908
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Tidskriftsartikel (refereegranskat)abstract
- Context: Polymorphisms in genes involved in regulation, biosynthesis, metabolism, and actions of testicular sex hormones may influence hormone balance and phenotype of aging men. Objective: We investigated the relationships between polymorphisms in genes related to pituitary-testicular endocrine function and health status. Design and Setting: Using cross-sectional baseline data, we conducted a multinational prospective cohort observational study consisting of a population survey of community-dwelling men. Participants: A total of 2748 men, aged 40-79 (mean +/- SD, 60.2 + 11.2) yr, were randomly recruited from eight European centers. Forty-three polymorphisms were genotyped in the following genes: androgen receptor (AR), estrogen receptor-alpha and -beta (ESR1 and ESR2), steroid 5alpha-reductase type II (SRD5A2), 17alpha-hydroxylase/17,20-lyase (CYP17A1), aromatase (CYP19A1), sex hormone-binding globulin (SHBG), LH beta-subunit (LHB), and LH receptor (LHCGR). Main Outcome Measures: We measured the associations between gene polymorphisms and endocrine, metabolic, and phenotypic parameters related to aging and sex hormone action. Results: Several polymorphisms in SHBG, ESR2, AR, CYP19A1, and LHB were significantly associated with circulating levels of SHBG, LH, total, free, and bioavailable testosterone and estradiol, the LH x testosterone product, and indices of insulin sensitivity. Apart from several previously reported associations between genes affecting estrogen levels and heel ultrasound parameters, no associations existed between polymorphisms and nonhormonal variables (anthropometry, blood lipids, blood pressure, hemoglobin, prostate symptoms, prostate-specific antigen, sexual dysfunction, cognition). Conclusion: In aging men, polymorphisms in genes related to the pituitary-testicular endocrine function significantly influence circulating LH, testosterone, and estradiol levels, but the downstream effects may be too small to influence secondary phenotypic parameters.
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| 6. |
- Huhtaniemi, Ilpo T, et al.
(författare)
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Increased Estrogen Rather Than Decreased Androgen Action Is Associated with Longer Androgen Receptor CAG Repeats.
- 2009
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 94, s. 277-284
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Tidskriftsartikel (refereegranskat)abstract
- Context: The individual variability in the waning androgenic-anabolic functions of aging men may be influenced by the CAG repeat polymorphism in exon 1 of the androgen receptor (AR), affecting androgen sensitivity. However, findings on its phenotypic effects are inconclusive. Objective: To investigate the relationships between health status, various reproductive hormones and the AR CAG repeat length. Design: A multi-national prospective cohort observational study - cross-sectional baseline data. Setting: Population survey of community-dwelling men. Participants: Men (40-79-yr-old; n=3,369) randomly recruited from centers in eight European countries; CAG repeat analysis was performed in 2,878 men. Main outcome measures: The correlations of the CAG repeat length with selected endocrine, metabolic and phenotypic parameters related to aging and sex hormone action. Results: Only minor differences were found in CAG repeat lengths between the eight European countries. They showed significant positive association with total, free and bioavailable levels of testosterone (T) and estradiol (E2). FSH but not LH correlated inversely with CAG repeat length. Significant associations were found with bone ultrasound parameters at the calcaneus. Negative correlation was found with triglycerides, but not with other blood lipids, or with anthropometry, blood pressure, hemoglobin, insulin sensitivity, or sexual and prostatic functions. Conclusions: The AR CAG repeat length correlates significantly with serum T and E2 of aging men. Weaker transcriptional activity of the AR with longer CAG-encoded polyglutamine repeats appears to be totally or near-totally compensated for by higher T levels. The residual phenotypic correlations may reflect differences in estrogen levels/actions following aromatization of the higher T levels.
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| 7. |
- Lundin, Kristina, et al.
(författare)
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Frequent finding of the androgen receptor A645D variant in normal population.
- 2006
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 91:2006 May 16, s. 3228-3231
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Tidskriftsartikel (refereegranskat)abstract
- Background: The androgen receptor A645D mutation has been described in one patient with ambiguous genitalia and one boy with normal phenotype. Objective: Because of this phenotypic variation, we screened a cohort of men from the general population (n = 293) as well as men with the following disorders of the genital tract for the mutation: men with prostate cancer (n = 89), testicular cancer (n = 87), and infertility (n = 103). We also investigated the influence of the polymorphic CAG and GGN repeats on the phenotypic outcome. Results: The A645D variant was found in three men from the general population (1.0%). These men did not differ regarding testosterone or LH concentrations, compared with the rest of this population. In addition, two men with prostate cancer (2.3%) and one infertile man (1.0%) presented with the mutation. No statistical differences in frequency were noted between the study groups, and none of these individuals had any genital malformations. All men who presented with the mutation carried an extraordinarily short GGN repeat of 10 base triplets in combination with long CAG repeats of 26-28 (average 27.3). In contrast, men with GGN = 10, but CAG less than 26 did not have the A645D mutation. A single-nucleotide polymorphism analysis revealed that the A645D variant has emerged from the most common haplogroup in our population. Conclusions: We conclude that the A645D mutation, which is present in 1% of the general Swedish population, is linked to GGN10 and long CAG repeats. Its effect on androgen receptor function is currently unknown.
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| 8. |
- Malm, Gunilla, et al.
(författare)
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Reproductive function during summer and winter in Norwegian men living north and south of the Arctic circle.
- 2004
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 89:9, s. 4397-4402
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Tidskriftsartikel (refereegranskat)abstract
- Seasonal, daylight-dependent variation in human spermatozoa counts, with lowest values during summer, has been suggested. To test this hypothesis, we performed a longitudinal study of semen quality and reproductive hormone levels in Norwegian men living north and south of the Arctic Circle. An ejaculate and a serum specimen were obtained both in summer and in winter from 92 volunteers in Tromsoe (69° north latitude) and 112 in Oslo (60° north latitude). Semen analyses were performed, and serum was assayed for FSH and inhibin B. The median spermatozoa concentration in Tromsoe after adjustment for abstinence period length was 49 × 106/ml in summer and 54 × 106/ml in winter. Corresponding values for Oslo were 59 × 106/ml and 54 × 106/ml. The seasonal differences in spermatozoa concentration were not statistically significant, nor were significant differences observed in median total spermatozoa count, semen volume, percentage progressive motile spermatozoa, or FSH. In Tromsoe, but not Oslo, inhibin B concentration was slightly, but significantly (P = 0.02) higher in winter than summer (229 ng/liter vs. 223 ng/liter).The length of the daylight period may have a slight impact on hormonal markers of spermatogenesis but does not cause substantial changes in spermatozoa numbers and motility.
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| 9. |
- O'Connor, Daryl B, et al.
(författare)
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The Relationships between Sex Hormones and Sexual Function in Middle-Aged and Older European Men.
- 2011
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 96, s. 1577-1587
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Tidskriftsartikel (refereegranskat)abstract
- Context: Limited data are available exploring the associations between sex hormones, multiple domains of sexual functioning, and sexual function-related distress in nonpatient samples in Europe. Objectives: The aim of the study was to investigate the relationships between serum testosterone (T), estradiol (E2), and dihydrotestosterone (DHT) and sexual function in a multicenter population-based study of aging in men. Design: Using stratified random sampling, 2838 men aged 40-79 yr completed the European Male Ageing Study-Sexual Function Questionnaire and provided a blood sample for hormone measurements. T, E2, and DHT were measured using gas chromatography-mass spectrometry. Setting: We conducted a community-based population survey in eight European centers. Main Outcome Measures: Self-reported sexual function (overall sexual function, sexual function-related distress, erectile dysfunction, masturbation) was measured. Results: Total and free T, but not E2 or DHT, was associated with overall sexual function in middle-aged and older men. E2 was the only hormone associated with sexual function-related distress such that higher levels were related to greater distress. Free T levels were associated with masturbation frequency and erectile dysfunction in the fully adjusted models, such that higher T was associated with less dysfunction and greater frequency. Moreover, there was a T threshold for the relationship between total T, sexual function, and erectile dysfunction. At T concentrations of 8 nmol/liter or less, T was associated with worse sexual functioning, whereas at T levels over 8 nmol/liter, the relationship came to a plateau. Conclusions: These findings suggest that different hormonal mechanisms may regulate sexual functioning (T) vs. the psychological aspects (E2) of male sexual behavior. Moreover, there was a T threshold for overall sexual function such that at levels greater than 8 nmol/liter the relationship between T and sexual function did not become stronger.
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| 10. |
- Ohlsson, Claes, 1965, et al.
(författare)
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Comparisons of Immunoassay and Mass Spectrometry Measurements of Serum Estradiol Levels and Their Influence on Clinical Association Studies in Men
- 2013
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Ingår i: Journal of Clinical Endocrinology & Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 98:6, s. E1097-E1102
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Tidskriftsartikel (refereegranskat)abstract
- Context: Immunoassay-based techniques, routinely used to measure serum estradiol (E2), are known Objective: Our objective was to compare immunoassay and MS measurements of E2 levels in men and Design and Setting: Middle-aged and older male subjects participating in the population-based Main Outcome Measures: Immunoassay and MS measurements of serum E2 were compared and Results: Within each cohort, serum E2 levels obtained by immunoassay and MS correlated moderately Conclusions: Our findings suggest interference in the immunoassay E2 analyses, possibly by CRP or a
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