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- Huhtaniemi, Ilpo T, et al.
(author)
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Increased Estrogen Rather Than Decreased Androgen Action Is Associated with Longer Androgen Receptor CAG Repeats.
- 2009
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In: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 94, s. 277-284
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Journal article (peer-reviewed)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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| 2. |
- Pye, Stephen R., et al.
(author)
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Influence of Insulin-Like Growth Factor Binding Protein (IGFBP)-1 and IGFBP-3 on Bone Health: Results from the European Male Ageing Study
- 2011
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In: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 88:6, s. 503-510
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Journal article (peer-reviewed)abstract
- The aim of this study was to determine the influence of insulin-like growth factor binding protein (IGFBP)-1, IGFBP-3, and IGF-I on calcaneal ultrasound parameters in middle-aged and elderly European men. Men aged 40-79 years were recruited from population registers for participation in the European Male Ageing Study (EMAS). Subjects were invited by letter to complete a postal questionnaire and to attend for an interviewer-assisted questionnaire, quantitative ultrasound (QUS) of the calcaneus, and a fasting blood sample from which serum levels of IGFBP-1, IGFBP-3, IGF-I, estradiol (E-2), and SHBG were assayed. The questionnaires included the Physical Activity Scale for the Elderly (PASE) and questions about smoking and alcohol consumption. Estimated bone mineral density (eBMD) was derived as a function of the QUS parameters speed of sound and broadband ultrasound attenuation. Height and weight were measured in all subjects. 3057 men, mean age 59.7 years (standard deviation 11.0) were included in the analysis. After adjusting for age, center, and BMI, higher levels of IGFBP-1 were associated with lower eBMD. Higher levels of both IGFBP-3 and IGF-I were associated with higher eBMD. After further adjustment for PASE score, current smoking, alcohol consumption, free E-2, and SHBG, IGFBP-3 and IGF-I, though not IGFBP-1, remained significantly associated with eBMD. IGFBP-1 was associated with bone health, though the effect could be explained by other factors. IGFBP-3 and IGF-I were independent determinants of bone health in middle-aged and elderly European men.
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| 3. |
- Pye, Stephen R., et al.
(author)
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Influence of Lifestyle Factors on Quantitative Heel Ultrasound Measurements in Middle-Aged and Elderly Men
- 2010
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In: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 86:3, s. 211-219
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Journal article (peer-reviewed)abstract
- We examined the distribution of quantitative heel ultrasound (QUS) parameters in population samples of European men and looked at the influence of lifestyle factors on the occurrence of these parameters. Men aged between 40 and 79 years were recruited from eight European centers and invited to attend for an interviewer-assisted questionnaire, assessment of physical performance, and quantitative ultrasound (QUS) of the calcaneus (Hologic; Sahara). The relationships between QUS parameters and lifestyle variables were assessed using linear regression with adjustments for age, center, and weight. Three thousand two hundred fifty-eight men, mean age 60.0 years, were included in the analysis. A higher PASE score (upper vs. lower tertile) was associated with a higher BUA (beta coefficient = 2.44 dB/Mhz), SOS (beta = 6.83 m/s), and QUI (beta = 3.87). Compared to those who were inactive, those who walked or cycled more than an hour per day had a higher BUA (beta = 3.71 dB/Mhz), SOS (beta = 6.97 m/s), and QUI (beta = 4.50). A longer time to walk 50 ft was linked with a lower BUA (beta = -0.62 dB/Mhz), SOS (beta = -1.06 m/s), and QUI (beta = -0.69). Smoking was associated with a reduction in BUA, SOS, and QUI. There was a U-shaped association with frequency of alcohol consumption. Modification of lifestyle, including increasing physical activity and stopping smoking, may help optimize bone strength and reduce the risk of fracture in middle-aged and elderly European men.
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