| 1. |
- Lagerquist, Marie, et al.
(författare)
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Androgens and the skeleton.
- 2005
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Ingår i: Minerva endocrinologica. - 0391-1977. ; 30:1, s. 15-25
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Tidskriftsartikel (refereegranskat)abstract
- Loss of estrogens or androgens causes bone loss by increasing the rate of bone remodeling, and also causes an imbalance between resorption and formation by prolonging the lifespan of osteoclasts and shortening the lifespan of osteoblasts. Conversely, treatment with androgens, as well as estrogens, maintains cancellous bone mass and integrity, regardless of age or sex. Both androgens, via the androgen receptor (AR), and estrogens, via the estrogen receptors (ERs) can exert these effects, but the relative contribution of these 2 pathways remains uncertain. Androgens, like estrogens, stimulate endochondral bone formation at the start of puberty, whereas they induce epiphyseal closure at the end of puberty, thus, they have a biphasic effect. Androgen action on the growth plate is, however, clearly mediated via aromatization into estrogens and interaction with ER alpha. Androgens increase, while estrogens decrease radial growth. This differential effect of the sex steroids may be important because bone strength in males seems to be determined by higher periosteal bone formation and, therefore, greater bone dimensions. Experiments in mice suggest that both the AR and ER alpha pathways are involved in androgen action on radial bone growth. ER beta may mediate growth-limiting effects of estrogens in the female but does not seem to be involved in the regulation of bone size in males. In conclusion, androgens may protect men against osteoporosis via maintenance of cancellous bone mass and expansion of cortical bone. This androgen action on bone is mediated by the AR and ER alpha.
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| 2. |
- Lee, David M., et al.
(författare)
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Association between 25-hydroxyvitamin D levels and cognitive performance in middle-aged and older European men
- 2009
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Ingår i: Journal of Neurology, Neurosurgery and Psychiatry. - : BMJ. - 1468-330X .- 0022-3050. ; 80:7, s. 722-729
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Tidskriftsartikel (refereegranskat)abstract
- Background: Although there is evidence that vitamin D inadequacy may be linked to adverse cognitive outcomes, results from studies on this topic have been inconsistent. The aim of this trial was to examine the association between 25-hydroxyvitamin D (25(OH) D) levels and cognitive performance in middle-aged and older European men. Methods: This population-based cross-sectional study included 3,369 men aged 40-79 years from eight centres enrolled in the European Male Ageing Study. Cognitive function was assessed using the Rey-Osterrieth Complex Figure (ROCF) test, the Camden Topographical Recognition Memory (CTRM) test and the Digit Symbol Substitution Test (DSST). Serum 25(OH) D levels were measured by radioimmunoassay. Additional assessments included measurement of physical activity, functional performance and mood/depression. Associations between cognitive function and 25(OH) D levels were explored using locally weighted and linear regression models. Results: In total, 3,133 men (mean (+/- SD) age 60 +/- 11 years) were included in the analysis. The mean (+/- SD) 25(OH) D concentration was 63 +/- 31 nmol/l. In age-adjusted linear regressions, high levels of 25(OH) D were associated with high scores on the copy component of the ROCF test (beta per 10 nmol/l = 0.096; 95% CI 0.049 to 0.144), the CTRM test (beta per 10 nmol/l= 0.075; 95% CI 0.026 to 0.124) and the DSST (beta per 10 nmol/l = 0.318; 95% CI 0.235 to 0.401). After adjusting for additional confounders, 25(OH) D levels were associated with only score on the DSST (beta per 10 nmol/l = 0.152; 95% CI 0.051 to 0.253). Locally weighted and spline regressions suggested the relationship between 25(OH) D concentration and cognitive function was most pronounced at 25(OH) D concentrations below 35 nmol/l. Conclusion: In this study, lower 25(OH) D levels were associated with poorer performance on the DSST. Further research is warranted to determine whether vitamin D sufficiency might have a role in preserving cognitive function in older adults.
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| 3. |
- Lee, David M., et al.
(författare)
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Association of hypogonadism with vitamin D status: the European Male Ageing Study
- 2012
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 166:1, s. 77-85
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Interrelationships between hormones of the hypothalamic-pituitary-testicular (HPT) axis, hypogonadism, vitamin D and seasonality remain poorly defined. We investigated whether HPT axis hormones and hypogonadism are associated with serum levels of 25-hydroxyvitamin D (25(OH)D) in men. Design and methods: Cross-sectional survey of 3369 community-dwelling men aged 40-79 years in eight European centres. Testosterone (T), oestradiol (E(2)) and dihydrotestosterone were measured by gas chromatography-mass spectrometry; LH, FSH, sex hormone binding globulin (SHBG), 25(OH)D and parathyroid hormone by immunoassay. Free T was calculated from total T, SHBG and albumin. Gonadal status was categorised as eugonadal (normal T/LH), secondary (low T, low/normal LH), primary (low T, elevated LH) and compensated (normal T, elevated LH) hypogonadism. Associations of HPT axis hormones with 25(OH)D were examined using linear regression and hypogonadism with vitamin D using multinomial logistic regression. Results: In univariate analyses, free T levels were lower (P=0.02) and E(2) and LH levels were higher (P<0.05) in men with vitamin D deficiency (25(OH)D <50 nmol/l). 25(OH)D was positively associated with total and free T and negatively with E(2) and LH in age- and centre-adjusted linear regressions. After adjusting for health and lifestyle factors, no significant associations were observed between 25(OH)D and individual hormones of the HPT axis. However, vitamin D deficiency was significantly associated with compensated (relative risk ratio (RRR)=1.52, P=0.03) and secondary hypogonadism (RRR=1.16, P=0.05). Seasonal variation was only observed for 25(OH)D (P<0.001). Conclusions: Secondary and compensated hypogonadism were associated with vitamin D deficiency and the clinical significance of this relationship warrants further investigation.
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| 4. |
- Lee, David M., et al.
(författare)
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Lower vitamin D levels are associated with depression among community-dwelling European men
- 2011
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Ingår i: Journal of Psychopharmacology. - : SAGE Publications. - 1461-7285 .- 0269-8811. ; 25:10, s. 1320-1328
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Tidskriftsartikel (refereegranskat)abstract
- Low serum 25-hydroxyvitamin D (25(OH)D) and elevated parathyroid hormone (PTH) Levels have been linked with depressive symptoms among adults in various clinical settings. Data in generally healthy, community-dwelling individuals remain inconclusive. We investigated whether depression was associated with 25(OH)D and/or PTH in a sample of middle-aged and older men (n = 3369; mean age 60 +/- 11) participating in the European Male Ageing Study, and whether any associations were explained by lifestyle and health factors. The Beck Depression Inventory-II (BDI-II) was used to screen for depression, and serum 25(OH)D and PTH levels measured by radioimmunoassay. Univariate analysis revealed that 25(OH)D levels were lower (p < 0.001) and PTH higher (p = 0.004) in people with depression. In age- and centre-adjusted linear regressions a higher BDI-II score was significantly associated with tower levels of 25(OH)D (p = 0.004). After adjustment for lifestyle and health factors this relationship was attenuated but remained significant (p = 0.01). Using multivariable logistic regression the odds for depression increased approximately 70% across decreasing 25(OH)D quartiles (p(trend) = 0.04). There was no independent association between PIN and depression in any of the muttivariable regressions. Our results reveal an inverse association between 25(OH)D levels and depression, largely independent of several lifestyle and health factors. Further studies are required to determine whether higher levels of vitamin D have an antidepressant effect in older adults.
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| 5. |
- Lee, David M., et al.
(författare)
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Vitamin D, parathyroid hormone and the metabolic syndrome in middle-aged and older European men
- 2009
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 161:6, s. 947-954
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Low serum 25-hydroxyviatmin D (25(OH)D) and elevated parathyroid hormone (PTH) levels have been linked to insulin resistance, the metabolic syndrome (MetS) and its components. Data in healthy, community-dwelling Europeans are lacking, and previous studies have not excluded subjects receiving drug treatments that may distort the relationship between 25(OH)D/PTH and MetS. The aim of our analysis was to examine the association of 25(OH)D and PTH with Adult Treatment Panel III-defined MetS in middle-aged and older European men Design: This was a population-based, cross-sectional study of 3369 men aged 40-79 years enrolled in the European Male Ageing Study. Results After exclusion of subjects with missing data. 3069 men with a mean (+/- S.D.) age of 60 +/- 11 years were included in the analysis. Age-adjusted 25(OH)D levels were inversely associated with waist circumference, systolic blood pressure (BP), triglycerides, and glucose (all P < 0.01) Age-adjusted PTH levels were only associated with waist and diastolic BP (both P < 0.05). After adjusting for age, centre, season and lifestyle factors the odds for MetS decreased across increasing 25(OH)D quintiles (odds ratios 0.48 (95% confidence intervals 0.36-0.64) highest versus lowest quintile. P-trend < 0.001). This relationship was unchanged after adjustment for PTH, but was attenuated after additional adjustment for homeostasis model assessment of insulin resistance (0.60 (0.47-0.78) P-trend < 0.001) There was no association between PTH and MetS. Conclusions: Our results demonstrate an inverse relationship between 25(OH)D levels and MetS, which is independent of several confounders and PTH. The relationship is partly explained by insulin resistance. The clinical significance of these observations warrants further study
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| 6. |
- McBeth, John, et al.
(författare)
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Musculoskeletal pain is associated with very low levels of vitamin D in men: results from the European Male Ageing Study
- 2010
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 69:8, s. 1448-1452
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Tidskriftsartikel (refereegranskat)abstract
- Introduction A study was undertaken to test the hypothesis that musculoskeletal pain is associated with low vitamin D levels but the relationship is explained by physical inactivity and/or other putative confounding factors. Methods Men aged 40-79 years completed a postal questionnaire including a pain assessment and attended a clinical assessment (lifestyle questionnaire, physical performance tests, 25-hydroxyvitamin D3 (25-(OH) D) levels from fasting blood sample). Subjects were classified according to 25-(OH) D levels as 'normal' (>= 15 ng/ml) or 'low' (<15 ng/ml). The relationship between pain status and 25-(OH) D levels was assessed using logistic regression. Results are expressed as ORs and 95% CIs. Results 3075 men of mean (SD) age 60 (11) years were included in the analysis. 1262 (41.0%) subjects were pain-free, 1550 (50.4%) reported 'other pain' that did not satisfy criteria for chronic widespread pain (CWP) and 263 (8.6%) reported CWP. Compared with patients who were pain-free, those with 'other pain' and CWP had lower 25-(OH) D levels (n = 239 (18.9%), n = 361 (23.3) and n = 67 (24.1%), respectively, p < 0.05). After adjusting for age, having 'other pain' was associated with a 30% increase in the odds of having low 25-(OH) D while CWP was associated with a 50% increase. These relationships persisted after adjusting for physical activity levels. Adjusting for additional lifestyle factors (body mass index, smoking and alcohol use) and depression attenuated these relationships, although pain remained moderately associated with increased odds of 20% of having low vitamin D levels. Conclusions These findings have implications at a population level for the long-term health of individuals with musculoskeletal pain.
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| 7. |
- McBeth, John, et al.
(författare)
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Perturbed Insulin-like Growth Factor-1 (IGF-1) and IGF Binding Protein-3 Are Not Associated with Chronic Widespread Pain in Men: Results from the European Male Ageing Study.
- 2009
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Ingår i: Journal of Rheumatology. - : The Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 36, s. 2523-2530
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To determine whether perturbations of insulin-like growth factor-1 (IGF-1) and IGF binding protein-3 (IGFBP-3) were associated with the presence of chronic widespread pain (CWP) in men. METHODS: The European Male Ageing Study (EMAS) is an 8-center population-based study of men aged 40-79 years recruited from population registers. A questionnaire asked about the presence and duration of musculoskeletal pain, from which subjects reporting CWP were identified. Subjects also had an interviewer-assisted questionnaire: levels of physical activity and mood were assessed, and height and weight were measured. IGF-1 and IGFBP-3 were assayed from a fasting blood sample. Logistic regression models were used to determine the association between IGF measures and CWP. Results were expressed as odds ratios or relative risk ratios. RESULTS: A total of 3206 subjects provided full data. Of those, 1314 (39.0%) reported no pain in the past month and 278 (8.3%) reported pain that satisfied criteria for CWP. IGF-1 concentrations were similar among subjects who reported no pain and those with CWP: 131.5 mg/l and 128.4 mg/l, respectively. This was true also for IGFBP-3 (4.3 and 4.3 mg/l). Obesity was associated with low IGF-1 and a high IGFBP-3/IGF-1 ratio, indicating less bioavailable IGF-1, irrespective of pain status. This relationship persisted after adjustment for comorbidities, depression, smoking, alcohol consumption, and quality of life. CONCLUSION: Overall CWP was not associated with perturbations in IGF-1 and IGFBP-3 concentrations. Hypofunctioning of the axis was noted among subjects who were obese and this was not specific to CWP. These data suggest that IGF-1 is unlikely to be etiologically important in relation to CWP, although the relationship with growth hormone remains to be elucidated.
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| 8. |
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| 9. |
- Ophoff, Jill, et al.
(författare)
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Physical activity in the androgen receptor knockout mouse: evidence for reversal of androgen deficiency on cancellous bone.
- 2009
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Ingår i: Biochemical and biophysical research communications. - : Elsevier BV. - 1090-2104 .- 0006-291X. ; 378:1, s. 139-44
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Tidskriftsartikel (refereegranskat)abstract
- Disruption of the androgen receptor (AR) in male mice reduces cortical bone expansion and muscle mass during puberty and results in high bone turnover-related cancellous osteopenia. We hypothesized that voluntary wheel running during growth is able to rescue the effects of AR disruption on bone. To this end, 5-week-old AR knockout (ARKO) mice were randomized to a running group (cage with running wheel) and a sedentary group (cage without wheel) and followed-up until 16 weeks of age. Voluntary wheel running in ARKO mice did not influence body weight, muscle mass or periosteal bone expansion. Interestingly, voluntary running significantly reduced bone turnover in ARKO mice and prevented cancellous bone loss due to a preservation of trabecular number. Thus, voluntary running in ARKO mice was able to reduce cancellous bone resorption, suggesting that sustained exercise may potentially compensate the effects of androgen disruption on cancellous bone.
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| 10. |
- Vandenput, Liesbeth, 1974, et al.
(författare)
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Role of the androgen receptor in skeletal homeostasis: the androgen-resistant testicular feminized male mouse model.
- 2004
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Ingår i: Journal of bone and mineral research. - 0884-0431. ; 19:9, s. 1462-70
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Tidskriftsartikel (refereegranskat)abstract
- The role of androgen receptor-mediated androgen action on bone was investigated in testicular feminized male (Tfm) mice. Cortical bone was found to be unresponsive to testosterone (T) in orchidectomized Tfm mice, whereas cortical thickness as well as trabecular BMD and structure were fully maintained by T in the corresponding Tabby control mice. These data show an essential role for androgen receptor-mediated androgen action in periosteal bone formation. INTRODUCTION: Androgens can affect the male skeleton both directly-through activation of the androgen receptor (AR)-and indirectly-through stimulation of estrogen receptors after aromatization. We assessed the importance of AR-mediated androgen action on bone in a mouse model of androgen resistance. MATERIALS AND METHODS: Eight-week-old androgen-resistant testicular feminized male (Tfm) and Tabby control mice were orchidectomized (ORX) and treated for 4 weeks with a slow-release testosterone (T) pellet (delivering 167 microg/day) or a placebo pellet. A comprehensive analysis of the skeletal effects of androgen deficiency and replacement was performed using histomorphometry, QCT, and biochemical assessment of bone turnover. RESULTS: As expected, T increased trabecular BMD, volume, number, and width in ORX Tabby mice. In ORX Tfm mice, however, T had less effect on trabecular BMD and no effect on trabecular bone structure. T action on trabecular bone was associated with opposite changes in bone turnover: trabecular and endocortical bone turnover and serum levels of osteocalcin were all reduced by T in ORX Tabby mice, but not in ORX Tfm mice. T also increased cortical thickness (+16%), area, and density in ORX Tabby mice, but not in Tfm mice, resulting in greater bone strength in the Tabby control strain. The positive effects of T on cortical bone reflected a stimulatory effect on periosteal bone formation (+137%), which was again absent in Tfm mice. CONCLUSIONS: These data show that, in male mice, AR-mediated T action is essential for periosteal bone formation and contributes to trabecular bone maintenance.
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