| 1. |
- Eriksson, Anna-Lena, 1971, et al.
(författare)
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The Bone Sparing Effects of 2-Methoxyestradiol Are Mediated via Estrogen Receptor-α in Male Mice.
- 2016
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Ingår i: Endocrinology. - : The Endocrine Society. - 1945-7170 .- 0013-7227. ; 157:11, s. 4200-4205
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Tidskriftsartikel (refereegranskat)abstract
- 2-Methoxyestradiol (2ME2), a metabolite of 17β-estradiol (E2), exerts bone sparing effects in animal models. We hypothesized that the underlying mechanism is back conversion of 2ME2 to E2, which subsequently acts via estrogen receptor (ER)α. We measured serum E2 levels in orchidectomized wild-type (WT) mice treated with 2ME2 66.6 μg/d or placebo. In placebo-treated animals, E2 was below the detection limit. In 2ME2-treated mice, the serum E2 level was 4.97 ± 0.68 pg/mL. This corresponds to the level found in diesterus in cycling female mice. Next, we investigated bone parameters in orchidectomized WT and ERα knockout mice treated with 2ME2 or placebo for 35 days. 2ME2 (6.66 μg/d) preserved trabecular and cortical bone in WT mice. Trabecular volumetric-bone mineral density was 64 ± 20%, and trabecular bone volume/total volume was 60 ± 20% higher in the metaphyseal region of the femur in the 2ME2 group, compared with placebo (P < .01). Both trabecular number and trabecular thickness were increased (P < .01). Cortical bone mineral content in the diaphyseal region of the femur was 31 ± 3% higher in the 2ME2 group, compared with placebo (P < .001). This was due to larger cortical area (P < .001). Three-point bending showed an increased bone strength in WT 2ME2-treated animals compared with placebo (maximum load [Fmax] +19±5% in the 2ME2 group, P < .05). Importantly, no bone parameter was affected by 2ME2 treatment in ERα knockout mice. In conclusion, 2ME2 treatment of orchidectomized mice results in increased serum E2. ERα mediates the bone sparing effects of 2ME2. The likely mediator of this effect is E2 resulting from back conversion of 2ME2.
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| 2. |
- Ohlsson, Claes, 1965, et al.
(författare)
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Genetic determinants of serum testosterone concentrations in men.
- 2011
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Ingår i: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 7:10
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Tidskriftsartikel (refereegranskat)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.
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| 3. |
- Zhai, Guangju, et al.
(författare)
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Eight common genetic variants associated with serum DHEAS levels suggest a key role in ageing mechanisms.
- 2011
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Ingår i: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 7:4
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Tidskriftsartikel (refereegranskat)abstract
- Dehydroepiandrosterone sulphate (DHEAS) is the most abundant circulating steroid secreted by adrenal glands--yet its function is unknown. Its serum concentration declines significantly with increasing age, which has led to speculation that a relative DHEAS deficiency may contribute to the development of common age-related diseases or diminished longevity. We conducted a meta-analysis of genome-wide association data with 14,846 individuals and identified eight independent common SNPs associated with serum DHEAS concentrations. Genes at or near the identified loci include ZKSCAN5 (rs11761528; p = 3.15 × 10(-36)), SULT2A1 (rs2637125; p = 2.61 × 10(-19)), ARPC1A (rs740160; p = 1.56 × 10(-16)), TRIM4 (rs17277546; p = 4.50 × 10(-11)), BMF (rs7181230; p = 5.44 × 10(-11)), HHEX (rs2497306; p = 4.64 × 10(-9)), BCL2L11 (rs6738028; p = 1.72 × 10(-8)), and CYP2C9 (rs2185570; p = 2.29 × 10(-8)). These genes are associated with type 2 diabetes, lymphoma, actin filament assembly, drug and xenobiotic metabolism, and zinc finger proteins. Several SNPs were associated with changes in gene expression levels, and the related genes are connected to biological pathways linking DHEAS with ageing. This study provides much needed insight into the function of DHEAS.
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| 4. |
- Benrick, Anna, 1979, et al.
(författare)
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A non-conservative polymorphism in the IL-6 signal transducer (IL6ST)/gp130 is associated with myocardial infarction in a hypertensive population.
- 2008
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Ingår i: Regulatory peptides. - : Elsevier BV. - 0167-0115. ; 146:1-3, s. 189-96
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Tidskriftsartikel (refereegranskat)abstract
- Inflammation is a key component in the development of atherosclerosis, and myocardial infarction (MI); therefore we investigated the association between an interleukin-6 signal transducer (IL6ST)/gp130 polymorphism, gp130 function and risk of MI. Structural modeling suggested that a non-conservative single nucleotide polymorphism in the gp130, Gly148Arg, can change the stability and functional properties of the molecule. In vitro studies were done with BAF/3 cells lacking endogenous gp130. Cells stably transfected with the gp130 148Arg variant proliferated less and showed slightly lower STAT-3 phosphorylation in response to gp130 stimulation as compared to cells transfected with gp130 148Gly. In a prospectively followed hypertensive cohort we identified 167 patients who suffered a MI during the study and compared them to matched controls (mean age 57 years, 73% males, n=482). Carriers of the 148Arg variant (f(Arg)=0.12) of the gp130 receptor had decreased odds ratio for MI in univariate analysis (0.56, 95% CI 0.34-0.91, p=0.02). In conclusion, a genetically determined structural variant of the IL-6 receptor subunit gp130 is, independently of other known risk factors, associated with decreased risk of MI. The variant is also associated with decreased IL-6 responsiveness and could lead to a configuration change in the gp130 receptor.
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| 5. |
- Dalin, Frida, 1984-, et al.
(författare)
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Clinical and immunological characteristics of Autoimmune Addison's disease : a nationwide Swedish multicenter study
- 2017
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : Oxford University Press. - 0021-972X .- 1945-7197. ; 102:2, s. 379-389
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Studies on clinical and immunological features of Autoimmune Addison's disease (AAD) are needed to understand the disease burden and increased mortality.OBJECTIVE: To provide upgraded data on autoimmune comorbidities, replacement therapy, autoantibody profiles and cardiovascular risk factors.DESIGN, SETTING AND PARTICIPANTS: Cross sectional, population-based study. 660 AAD patients were included utilizing the Swedish Addison Registry (SAR) 2008-2014. When analyzing cardiovascular risk factors, 3,594 individuals from the population-based survey in Northern Sweden, MONICA (MONItoring of Trends and Determinants of CArdiovascular Disease), served as controls.MAIN OUTCOME MEASURE: Prevalence of autoimmune comorbidities and cardiovascular risk factors. Autoantibodies against 13 autoantigens were determined.RESULTS: Sixty percent of the SAR cohort consisted of females. Mean age at diagnosis was significantly higher for females than for males (36.8 vs. 31.1 years). The proportion of 21-hydroxylase autoantibody positive patients was 83% and 62% of patients had one or more associated autoimmune diseases, more frequently coexisting in females (p<0.0001). AAD patients had lower BMI (p<0.0001) and prevalence of hypertension (p=0.027) compared with controls. Conventional hydrocortisone tablets were used by 89% of patients; with the mean dose 28.1±8.5 mg/day. The mean hydrocortisone equivalent dose normalized to body surface was 14.8±4.4 mg/m(2)/day. Higher hydrocortisone equivalent dose was associated with higher incidence of hypertension (p=0.046).CONCLUSIONS: Careful monitoring of AAD patients is warranted to detect associated autoimmune diseases. Contemporary Swedish AAD patients do not have increased prevalence of overweight, hypertension, T2DM or hyperlipidemia. However, high glucocorticoid replacement doses may be a risk factor for hypertension.
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| 6. |
- Eriksson, Anna-Lena, 1971, et al.
(författare)
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Genetic Determinants of Circulating Estrogen Levels and Evidence of a Causal Effect of Estradiol on Bone Density in Men.
- 2018
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 103:3, s. 991-1004
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Tidskriftsartikel (refereegranskat)abstract
- Serum estradiol (E2) and estrone (E1) levels exhibit substantial heritability.To investigate the genetic regulation of serum E2 and E1 in men.Genome-wide association study in 11,097 men of European origin from nine epidemiological cohorts.Genetic determinants of serum E2 and E1 levels.Variants in/near CYP19A1 demonstrated the strongest evidence for association with E2, resolving to three independent signals. Two additional independent signals were found on the X chromosome; FAMily with sequence similarity 9, member B (FAM9B), rs5934505 (P = 3.4 × 10-8) and Xq27.3, rs5951794 (P = 3.1 × 10-10). E1 signals were found in CYP19A1 (rs2899472, P = 5.5 × 10-23), in Tripartite motif containing 4 (TRIM4; rs17277546, P = 5.8 × 10-14), and CYP11B1/B2 (rs10093796, P = 1.2 × 10-8). E2 signals in CYP19A1 and FAM9B were associated with bone mineral density (BMD). Mendelian randomization analysis suggested a causal effect of serum E2 on BMD in men. A 1 pg/mL genetically increased E2 was associated with a 0.048 standard deviation increase in lumbar spine BMD (P = 2.8 × 10-12). In men and women combined, CYP19A1 alleles associated with higher E2 levels were associated with lower degrees of insulin resistance.Our findings confirm that CYP19A1 is an important genetic regulator of E2 and E1 levels and strengthen the causal importance of E2 for bone health in men. We also report two independent loci on the X-chromosome for E2, and one locus each in TRIM4 and CYP11B1/B2, for E1.
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| 7. |
- Eriksson, Anna-Lena, 1971, et al.
(författare)
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SHBG gene promoter polymorphisms in men are associated with serum sex hormone-binding globulin, androgen and androgen metabolite levels, and hip bone mineral density.
- 2006
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 91:12, s. 5029-37
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: SHBG regulates free sex steroid levels, which in turn regulate skeletal homeostasis. Twin studies have demonstrated that genetic factors largely account for interindividual variation in SHBG levels. Glucuronidated androgen metabolites have been proposed as markers of androgenic activity. OBJECTIVE: Our objective was to investigate whether polymorphisms in the SHBG gene promoter [(TAAAA)(n) microsatellite and rs1799941 single-nucleotide polymorphism] are associated with serum levels of SHBG, sex steroids, or bone mineral density (BMD) in men. DESIGN AND STUDY SUBJECTS: We conducted a population-based study of two cohorts of Swedish men: elderly men (MrOS Sweden; n congruent with 3000; average age, 75.4 yr) and young adult men (GOOD study; n = 1068; average age, 18.9 yr). MAIN OUTCOME MEASURES: We measured serum levels of SHBG, testosterone, estradiol, dihydrotestosterone, 5alpha-androstane-3alpha,17beta-diol glucuronides, androsterone glucuronide, and BMD determined by dual-energy x-ray absorptiometry. RESULTS: In both cohorts, (TAAAA)(n) and rs1799941 genotypes were associated with serum levels of SHBG (P < 0.001), dihydrotestosterone (P < 0.05), and 5alpha-androstane-3alpha,17beta-diol glucuronides (P < 0.05). In the elderly men, they were also associated with testosterone and BMD at all hip bone sites. The genotype associated with high levels of SHBG was also associated with high BMD. Interestingly, male mice overexpressing human SHBG had increased cortical bone mineral content in the femur, suggesting that elevated SHBG levels may cause increased bone mass. CONCLUSIONS: Our findings demonstrate that polymorphisms in the SHBG promoter predict serum levels of SHBG, androgens, and glucuronidated androgen metabolites, and hip BMD in men.
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| 8. |
- Eriksson, Anna-Lena, 1971, et al.
(författare)
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The COMT val158met polymorphism is associated with prevalent fractures in Swedish men.
- 2008
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Ingår i: Bone. - : Elsevier BV. - 8756-3282 .- 1873-2763. ; 42:1, s. 107-12
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Sex steroids are important for growth and maintenance of the skeleton. Catechol-O-methyltransferase (COMT) is an estrogen degrading enzyme. The COMT val158met polymorphism results in a 60-75% difference in enzyme activity between the val (high activity=H) and met (low activity=L) variants. We have previously reported that this polymorphism is associated with bone mineral density (BMD) in young men. The aim of this study was to investigate associations between COMT val158met, BMD and fractures in elderly men. METHODS: Population-based study of Swedish men 75.4, SD 3.2, years of age. Fractures were reported using standardized questionnaires. Fracture and genotype data were available from 2,822 individuals. RESULTS: Total number of individuals with self-reported fracture was 989 (35.0%). Prevalence of >or=1 fracture was 37.2% in COMT(LL), 35.7% in COMT(HL) and 30.4% in COMT(HH) (p<0.05). Early fractures (50 years of age). The OR for fracture of the non-weight bearing skeleton in COMT(HH) compared with COMT(LL+HL) was 0.74 (95% CI 0.59-0.92). No associations between COMT val158met and BMD were found in this cohort of elderly men. CONCLUSIONS: The COMT val158met polymorphism is associated with life time fracture prevalence in elderly Swedish men. This association is mainly driven by early fractures (
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| 9. |
- Justice, A. E., et al.
(författare)
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Genome-wide meta-analysis of 241,258 adults accounting for smoking behaviour identifies novel loci for obesity traits
- 2017
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Few genome-wide association studies (GWAS) account for environmental exposures, like smoking, potentially impacting the overall trait variance when investigating the genetic contribution to obesity-related traits. Here, we use GWAS data from 51,080 current smokers and 190,178 nonsmokers (87% European descent) to identify loci influencing BMI and central adiposity, measured as waist circumference and waist-to-hip ratio both adjusted for BMI. We identify 23 novel genetic loci, and 9 loci with convincing evidence of gene-smoking interaction (GxSMK) on obesity-related traits. We show consistent direction of effect for all identified loci and significance for 18 novel and for 5 interaction loci in an independent study sample. These loci highlight novel biological functions, including response to oxidative stress, addictive behaviour, and regulatory functions emphasizing the importance of accounting for environment in genetic analyses. Our results suggest that tobacco smoking may alter the genetic susceptibility to overall adiposity and body fat distribution.
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| 10. |
- Mellström, Dan, 1945, et al.
(författare)
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Free testosterone is an independent predictor of BMD and prevalent fractures in elderly men: MrOS Sweden.
- 2006
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Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - : Wiley. - 0884-0431. ; 21:4, s. 529-35
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Tidskriftsartikel (refereegranskat)abstract
- The role of androgens for bone health in elderly men is unclear. We show that free testosterone within the normal range is a predictor of BMD at predominantly cortical bone sites and of previous osteoporosis-related fractures in elderly Swedish men. INTRODUCTION: Osteoporosis-related fractures constitute a major health concern not only in women but also in men. Previous studies have clearly shown that serum levels of estradiol are associated with BMD, whereas more conflicting data have been presented regarding the predictive value of testosterone (T) for bone health in elderly men. The aim of this study was to investigate if serum levels of T are associated with BMD and/or prevalent fractures in a large cohort of elderly men. MATERIALS AND METHODS: In the Swedish part of the MrOS study (n = 2908; average age, 75.4 years), bone parameters were measured using DXA, and prevalent fractures were recorded using standardized questionnaires and by vertebral X-ray analyses. Serum levels of total T, total estradiol (E2), and sex hormone-binding globulin (SHBG) were measured by radioimmunoassay, and free T (FT) and free E2 (FE2) were derived from the mass action equations. Height, weight, age, physical activity, smoking habits, and calcium intake were included together with FT and FE2 in regression models for BMD. RESULTS: FT was an independent positive predictor of BMD in total body, total hip, femur trochanter, and arm but not in the lumbar spine. The highest independent predictive value of FT was found in the arm and the hip (with a relatively high content of cortical bone). FE2 was an independent predictor of BMD at all bone sites studied, and the highest predictive value was seen for lumbar spine (with relatively high content of trabecular bone) BMD. FT but not FE2 was a positive predictor of total body bone area and BMC. FT levels below the median were independent predictors of prevalent osteoporosis-related fractures (OR, 1.56; 95% CI, 1.14-2.14; p < 0.01) and X-ray-verified vertebral fractures (OR, 2.00; 95% CI, 1.34-2.86; p < 0.001). The predictive value of FT for prevalent fractures was not affected by adjustment for BMD. CONCLUSIONS: These findings show that variation of FT within the normal range is an independent but modest predictor of BMD at predominantly cortical bone sites and of previous osteoporosis-related fractures in elderly men. Our data indicate that not only estrogens but also androgens are of importance for bone health in elderly men. Longitudinal studies investigating the predictive value of T for fracture risk in elderly men are required.
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