| 31. |
- Nilsson, Martin, 1966, et al.
(author)
-
Competitive physical activity early in life is associated with bone mineral density in elderly Swedish men
- 2008
-
In: Osteoporosis International. - : Springer Science and Business Media LLC. - 0937-941X .- 1433-2965. ; 19:11, s. 1557-1566
-
Journal article (peer-reviewed)abstract
- In this population-based study of 75-year-old men (n = 498), we investigated the association between physical activity (PA) early in life and present bone mineral density (BMD). We demonstrate that a high frequency of competitive sports early in life is associated with BMD at several bone sites, indicating that increases in BMD following PA are preserved longer than previously believed. Introduction Physical activity (PA) increases bone mineral density (BMD) during growth. It is unclear if the positive effects remain at old age. In this study, we aimed to determine if PA early in life was associated with BMD in elderly men. Methods In this population-based study, 498 men, 75.2 +/- .3 (mean +/- SD) years old, were included. BMD was assessed using DXA. Data concerning lifetime PA, including both competitive (CS) and recreational sports (RS), and occupational physical load (OPL), were collected at interview. Results Subjects in the highest frequency group of CS in the early period (10-35 years), had higher BMD at the total body (4.2%, p < 0.01), total hip (7.0%, p < 0.01), trochanter (8.7%, p < 0.01), and lumbar spine (7.9%, p < 0.01), than subjects not involved in CS. A stepwise linear regression model showed that frequency of CS in the early period independently positively predicted present BMD at the total body (beta=0.12, p < 0.01), total hip (beta=0.11, p < 0.01), trochanter (beta=0.12, p < 0.01), and lumbar spine (beta=0.11, p=0.01). Conclusions We demonstrate that PA in CS early in life is associated with BMD in 75-year-old Swedish men, indicating that increases in BMD following PA are preserved longer than previously believed.
|
|
| 32. |
- Nilsson, Martin, 1966, et al.
(author)
-
Previous Sport Activity During Childhood and Adolescence is Associated with Increased Cortical Bone Size in Young Adult Men.
- 2009
-
In: Journal of bone and mineral research. - : Wiley. - 1523-4681 .- 0884-0431. ; 24:1, s. 125-33
-
Journal article (peer-reviewed)abstract
- Abstract Physical activity during growth has been associated with altered cortical bone geometry, but it remains uncertain if the physical activity induced increments in cortical bone size remain when the level of physical activity is diminished or ceased. The aim of this study was to investigate if physical activity during growth is associated with cortical bone geometry in currently inactive young men. In this study, 1068 men, 19.0 +/- 0.6 (mean+/-SD) years old, were included. Cortical bone geometry at the tibia and radius were measured using peripheral quantitative computerized tomography (pQCT). A standardized questionnaire was used to collect information about current and previous sport activity. Subjects who continued to be active (n=678) and who had been previously active (n=285) in sports had a wider cortical bone (periosteal circumference (PC) 4.5% and 3.2%, respectively) with increased cross sectional area (CSA; 12.5% and 6.9%) of the tibia, than the always inactive subjects (n=82). In the currently inactive men (n=367), regression analysis (including covariates age, height, weight, calcium intake, smoking, and duration of inactivity) revealed that previous sport activity was independently associated with cortical bone size of the tibia (CSA and PC). Amount of previous sport activity explained 7.3% of the total variation in cortical CSA. Subjects, who ceased their sport activity for up to 6.5 years previously, still had greater cortical PC and CSA of the tibia than always inactive subjects. The results from the present study indicate that sport activity during growth confers positive effects on bone geometry even though sport activity is ceased.
|
|
| 33. |
- Ribom, Eva L, et al.
(author)
-
Estimation of physical performance and measurements of habitual physical activity may capture men with high risk to fall--data from the Mr Os Sweden cohort.
- 2009
-
In: Archives of gerontology and geriatrics. - : Elsevier BV. - 1872-6976 .- 0167-4943. ; 49:1
-
Journal article (peer-reviewed)abstract
- To evaluate if clinically usable estimates of physical performance and level of habitual physical activity are associated with fall risk in elderly men. A population-based sample of 3014 randomly selected men aged 69-80 years was recruited to medical centers in Gothenburg, Malmoe, or Uppsala. The level of physical activity and self-reported falls during the preceding 12 months was evaluated using a questionnaire. The physical performance ability was estimated by measurements of handgrip strength, a timed stands test, a 6-m walking test and a 20-cm narrow walk test. Falls were reported in 16.5% of the men. Fallers performed 6.2+/-19.0% (mean+/-standard deviations; S.D.) less in right handgrip measures, 8.8+/-40.6% slower in the timed stands test, 6.8+/-30.8% slower in the 6-m walking test, and 5.3+/-28.8% slower in the 20-cm narrow walk test (all p<0.001, respectively). The odds ratio for falls among men who performed <-3 S.D. or failed compared to the mean (+1 S.D. to -1 S.D.) in the timed stands test was 3.41 (95% CI 2.31-5.02; p<0.001) and 2.46 (95% CI 1.80-3.34; p<0.001) in 20-cm narrow walk test. There were more fallers that never were physical active (73.0% vs. 65.4%, p<0.001) and who were sitting more (6.4+/-2.5 h/day vs. 6.0+/-2.3 h/day, p<0.05) than among the non-fallers. Fallers scored less than non-fallers in all the estimates of physical performance and they were more sedentary in their life style. The report suggests that clinical usable tests of physical performance and evaluation of habitual physical activity in the clinical situation possibly can be used to predict risk of falls in elderly men.
|
|
| 34. |
- Schulze, Jenny Jakobsson, et al.
(author)
-
Genetic aspects of epitestosterone formation and androgen disposition: influence of polymorphisms in CYP17 and UGT2B enzymes.
- 2008
-
In: Pharmacogenetics and genomics. - 1744-6872. ; 18:6, s. 477-85
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: Testosterone is a commonly abused androgen in sports and in the gym culture of the society. Its abuse is conventionally disclosed by urinary assay of the testosterone/epitestosterone (T/E) glucuronide ratio, which should not exceed 4. A noteworthy number of athletes, however, have higher natural ratios than 4, most likely because of decreased excretion of epitestosterone glucuronide. Falsely positive doping test results are of great concern for the legal rights of the sportsman. Our objective was to study the genetic aspects of epitestosterone formation, and to elucidate the impact of genetic variation in androgen-metabolizing enzymes. METHODS: Urine from different study populations was analysed for androgen glucuronides by gas chromatography-mass spectrometry. All men were genotyped for the uridine diphospho-glucuronosyltransferase (UGT) 2B17 deletion polymorphism and single nucleotide polymorphisms in the cytochrome P-450c17alpha (CYP17), UGT2B15 and UGT2B7 genes. Expression of UGT2B15 mRNA in human liver samples was analysed using real-time PCR. RESULTS: A T>C (A1>A2) promoter polymorphism in the CYP17 gene was associated with the urinary glucuronide levels of epitestosterone and its putative precursor androstene-3beta, 17alpha-diol, resulting in 64% higher T/E ratios in A1/A1 homozygotes. Individuals devoid of UGT2B17 had significantly higher UGT2B15 mRNA levels in liver than individuals carrying two functional UGT2B17 alleles. CONCLUSION: The CYP17 promoter polymorphism may partly explain high natural (>4) T/E ratios. Our data indicate that 5-androstene-3beta, 17alpha-diol is an important precursor of epitestosterone and that CYP17 is involved in its production. In addition, we found that lack of the UGT2B17 enzyme may be compensated for by increase in UGT2B15 transcription.
|
|
| 35. |
- Strandberg, Louise, 1981, et al.
(author)
-
Interleukin-1 system gene polymorphisms are associated with fat mass in young men.
- 2006
-
In: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 91:7, s. 2749-54
-
Journal article (peer-reviewed)abstract
- CONTEXT: There is growing evidence for interactions between the regulation of body fat and the immune system. Studies of knockout mice indicate that IL-1 has an antiobesity effect. OBJECTIVE: The objective of the study was to investigate our hypothesis that common polymorphisms of the IL-1 system, which are associated with IL-1 activity, also are associated with fat mass. DESIGN, SETTING, AND STUDY SUBJECTS: The Gothenburg Osteoporosis and Obesity Determinants (GOOD) study is a population-based cross-sectional study of 18- to 20-yr-old men (n = 1068), mostly Caucasian, from the Gothenburg area (Sweden). Three different polymorphisms, IL-1beta +3953 C/T, IL-1beta-31 T/C, and IL-1 receptor antagonist (IL-1RN) variable number tandem repeat of 86 bp, were investigated in relation to body fat mass. MAIN OUTCOME MEASURE: The main outcome measures were genotype distributions and their association with body fat mass in different compartments, measured with dual-energy x-ray absorptiometry. RESULTS: Carriers of the T variant (CT and TT) of the +3953 C to T (F(T) = 0.25) IL-1beta gene polymorphism had significantly lower total fat mass (P = 0.013) and also significantly reduced arm, leg, and trunk fat, compared with CC individuals. IL-1RN*2 carriers with two repeats of the IL-1RN variable number tandem repeat polymorphism had increased total fat (P = 0.036), serum leptin, and fat of trunk and arm as well as serum levels of IL-1RN and IL-1RN production ex vivo. The IL-1beta-31 polymorphism did not correlate with the fat measurements. CONCLUSIONS: The IL-1 system, recently shown to affect fat mass in experimental animals, contains gene polymorphisms that are associated with fat mass in young men.
|
|
| 36. |
- Swanson, Charlotte, 1975, et al.
(author)
-
Glucocorticoid regulation of osteoclast differentiation and expression of receptor activator of nuclear factor-kappaB (NF-kappaB) ligand, osteoprotegerin, and receptor activator of NF-kappaB in mouse calvarial bones.
- 2006
-
In: Endocrinology. - : The Endocrine Society. - 0013-7227 .- 1945-7170. ; 147:7, s. 3613-22
-
Journal article (peer-reviewed)abstract
- In the present study, dexamethasone treatment of neonatal mouse calvarial bones increased mRNA expression of tartrate-resistant acid phosphatase, calcitonin receptor (CTR), cathepsin K, carbonic anhydrase II, osteoprotegerin (OPG), and receptor activator of nuclear factor-kappaB (RANK) as well as mRNA and protein expression of RANK ligand (RANKL). The increase in OPG mRNA noted with dexamethasone was in contrast to 1,25(OH)(2)-vitamin D3 (D3) treatment, which decreased OPG expression. Stimulation of (45)Ca release by dexamethasone and hydrocortisone in calvariae was blocked by OPG. Stimulation of RANKL, RANK, OPG, and CTR mRNA expression by dexamethasone in calvariae was blocked by the glucocorticoid receptor antagonist RU 38,486. Greater than additive potentiations of CTR mRNA and RANKL mRNA and protein were observed when D3 and dexamethasone were combined. Vitamin D receptor mRNA was increased by dexamethasone and D3, whereas glucocorticoid receptor (GR) mRNA was decreased by dexamethasone and unaffected by D3. No synergistic interaction between dexamethasone and D3 on either vitamin D receptor or GR mRNA expression was noted. The data demonstrate that dexamethasone-induced bone resorption in calvarial bones is associated with increased differentiation of osteoclasts and regulation of the RANKL-RANK-OPG system. The increase in OPG expression and the decrease of GR expression noted with dexamethasone offer an explanation for why bone breakdown in mouse calvariae treated with glucocorticoids is less than that caused by resorptive agents like D3. The synergistic stimulation of RANKL by dexamethasone and D3 offers an explanation of how glucocorticoids and D3 interact to potentiate bone resorption.
|
|
| 37. |
- Swanson, Charlotte, 1975, et al.
(author)
-
Sex steroid levels and cortical bone size in young men are associated with a uridine diphosphate glucuronosyltransferase 2B7 polymorphism (H268Y).
- 2007
-
In: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:9, s. 3697-704
-
Journal article (peer-reviewed)abstract
- CONTEXT: Sex steroids are involved in the regulation of pubertal cortical bone expansion in males. In vitro studies have indicated that the enzyme uridine diphosphate glucuronosyltransferase (UGT) 2B7 has the capacity to glucuronidate sex steroids and their metabolites. OBJECTIVE: Our objective was to determine the impact of the H(268)Y polymorphism in the UGT2B7 gene on interindividual variation of serum levels of sex steroids and cortical bone dimensions. PARTICIPANTS: The population-based cohort Gothenburg Osteoporosis and Obesity Determinants study consists of 1068 young adult Swedish men (age 18.9 yr). MAIN OUTCOME MEASURES: Serum levels of sex steroids and the three major glucuronidated androgen metabolites, androstane-3alpha,17beta-diol-17glucuronide, androstane-3alpha,17beta-diol-3glucuronide, and androsterone-glucuronide, were analyzed. Cortical and trabecular volumetric bone mineral density and cortical bone size were measured by peripheral quantitative computer tomography. RESULTS: Serum levels of testosterone (YY 9% over HH; P < 0.01), dihydrotestosterone (YY 10% over HH; P < 0.01), and estradiol (YY 8% over HH; P < 0.01) were associated with the UGT2B7 H(268)Y polymorphism. The polymorphism was associated with androstane-3alpha,17beta-diol-17glucuronide and androstane-3alpha,17beta-diol-3glucuronide (P < 0.01), but not with androsterone-glucuronide serum levels. In addition, the UGT2B7 H(268)Y polymorphism was an independent predictor of cortical bone size, reflected by periosteal circumference and cortical moment of inertia (P < 0.01), in both the weight-bearing tibia and nonweight-bearing radius. CONCLUSIONS: The UGT2B7 H(268)Y polymorphism is independently associated with cortical bone size and serum sex steroid levels in young adult men. Subjects homozygous for the Y allele had higher serum testosterone and larger cortical bone size than subjects homozygous for the H allele. However, the underlying mechanism behind these associations is unknown and has to be studied further.
|
|
| 38. |
- Swanson, Charlotte, 1975, et al.
(author)
-
The UDP Glucuronosyltransferase 2B15 D85Y and 2B17 Deletion Polymorphisms Predict the Glucuronidation Pattern of Androgens and Fat Mass in Men.
- 2007
-
In: Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:12, s. 4878-82
-
Journal article (peer-reviewed)abstract
- Context: Previous in vitro studies have demonstrated that the UDP glucuronosyltransferase (UGT) 2B15 and UGT2B17 glucuronidate androgens and their metabolites. Objective: To determine in vivo if the UGT2B15 D(85)Y and the UGT2B17 deletion polymorphisms predict androgen glucuronidation and body composition. Participants: Two population-based cohorts including young adult (n=1068, age=18.9 years) and elderly (n=1001, age=75.3 years) men. Main Outcome Measures: Serum and urine levels of testosterone (T) and dihydrotestosterone (DHT) measured by GC-MS and serum levels of the major glucuronidated androgen metabolites androstane-3alpha,17beta-diol(androstanediol)-3glucuronide, androstanediol-17glucuronide and androsterone-glucuronide measured by LC-MS/MS. Body composition measured by DXA. Results: Both the UGT2B15 D(85)Y and the UGT2B17 deletion polymorphisms were associated with serum levels of androstanediol-17glucuronide (p<0.001) but not with levels of androstanediol-3glucuronide or androsterone-glucuronide in both cohorts. Glucuronidation of T and DHT was associated with the UGT2B17 deletion but not with the UGT2B15 D(85)Y polymorphism, suggested by strong associations between the deletion polymorphism and urine levels of these two hormones. Both polymorphisms were associated with several different measures of fat mass (p<0.01). The UGT2B17 deletion polymorphism was associated with insulin sensitivity (p<0.05) as indicated by the HOMA index. Conclusions: The UGT2B15 D(85)Y and the UGT2B17 deletion polymorphisms are both predictors of the glucuronidation pattern of androgens/androgen metabolites. Our findings indicate that UGT2B17 is involved in 17 glucuronidation of mainly T but also of DHT and androstanediol and that UGT2B15 is involved in the 17 glucuronidation of androstanediol. Furthermore, these two polymorphisms are predictors of fat mass in men.
|
|
| 39. |
- van Meurs, Joyce B, et al.
(author)
-
Large-scale analysis of association between LRP5 and LRP6 variants and osteoporosis.
- 2008
-
In: JAMA : the journal of the American Medical Association. - Chicago : American Medical Association (AMA). - 1538-3598 .- 0098-7484. ; 299:11, s. 1277-90
-
Journal article (peer-reviewed)abstract
- CONTEXT: Mutations in the low-density lipoprotein receptor-related protein 5 (LRP5) gene cause rare syndromes characterized by altered bone mineral density (BMD). More common LRP5 variants may affect osteoporosis risk in the general population. OBJECTIVE: To generate large-scale evidence on whether 2 common variants of LRP5 (Val667Met, Ala1330Val) and 1 variant of LRP6 (Ile1062Val) are associated with BMD and fracture risk. DESIGN AND SETTING: Prospective, multicenter, collaborative study of individual-level data on 37,534 individuals from 18 participating teams in Europe and North America. Data were collected between September 2004 and January 2007; analysis of the collected data was performed between February and May 2007. Bone mineral density was assessed by dual-energy x-ray absorptiometry. Fractures were identified via questionnaire, medical records, or radiographic documentation; incident fracture data were available for some cohorts, ascertained via routine surveillance methods, including radiographic examination for vertebral fractures. MAIN OUTCOME MEASURES: Bone mineral density of the lumbar spine and femoral neck; prevalence of all fractures and vertebral fractures. RESULTS: The Met667 allele of LRP5 was associated with reduced lumbar spine BMD (n = 25,052 [number of participants with available data]; 20-mg/cm2 lower BMD per Met667 allele copy; P = 3.3 x 10(-8)), as was the Val1330 allele (n = 24,812; 14-mg/cm2 lower BMD per Val1330 copy; P = 2.6 x 10(-9)). Similar effects were observed for femoral neck BMD, with a decrease of 11 mg/cm2 (P = 3.8 x 10(-5)) and 8 mg/cm2 (P = 5.0 x 10(-6)) for the Met667 and Val1330 alleles, respectively (n = 25 193). Findings were consistent across studies for both LRP5 alleles. Both alleles were associated with vertebral fractures (odds ratio [OR], 1.26; 95% confidence interval [CI], 1.08-1.47 for Met667 [2001 fractures among 20 488 individuals] and OR, 1.12; 95% CI, 1.01-1.24 for Val1330 [1988 fractures among 20,096 individuals]). Risk of all fractures was also increased with Met667 (OR, 1.14; 95% CI, 1.05-1.24 per allele [7876 fractures among 31,435 individuals)]) and Val1330 (OR, 1.06; 95% CI, 1.01-1.12 per allele [7802 fractures among 31 199 individuals]). Effects were similar when adjustments were made for age, weight, height, menopausal status, and use of hormone therapy. Fracture risks were partly attenuated by adjustment for BMD. Haplotype analysis indicated that Met667 and Val1330 variants both independently affected BMD. The LRP6 Ile1062Val polymorphism was not associated with any osteoporosis phenotype. All aforementioned associations except that between Val1330 and all fractures and vertebral fractures remained significant after multiple-comparison adjustments. CONCLUSIONS: Common LRP5 variants are consistently associated with BMD and fracture risk across different white populations. The magnitude of the effect is modest. LRP5 may be the first gene to reach a genome-wide significance level (a conservative level of significance [herein, unadjusted P < 10(-7)] that accounts for the many possible comparisons in the human genome) for a phenotype related to osteoporosis.
|
|
| 40. |
- Vandenput, Liesbeth, 1974, et al.
(author)
-
Androgens and Glucuronidated Androgen Metabolites are Associated with Metabolic Risk Factors in Men.
- 2007
-
In: Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:11, s. 4130-7
-
Journal article (peer-reviewed)abstract
- Context: Androgens are associated with metabolic risk factors in men. However, the independent impact of androgens and androgen metabolites on metabolic risk factors in men is unclear. Objective: Our objective was to determine the predictive value of serum levels of androgens and glucuronidated androgen metabolites for metabolic risk factors. Design and Study Subjects: We conducted a population-based study of two Swedish cohorts (1068 young adult and 1001 elderly men). Main Outcome Measures: We measured correlation of serum dihydrotestosterone (DHT), testosterone (T) and glucuronidated androgen metabolites with fat mass, fat distribution, serum lipids and insulin resistance. Results: Both DHT and T were negatively associated with different measures of fat mass in both cohorts (P<0.001). Further statistical analysis indicated that DHT, but not T, was independently negatively associated with different measures of fat mass and insulin resistance (P<0.001). The glucuronidated androgen metabolite androstane-3alpha,17beta-diol-17glucuronide (17G) was independently positively associated with fat mass (P<0.001). Most importantly, the 17G/DHT ratio was strongly correlated, not only with fat mass, but also with central fat distribution, intra-hepatic fat, disturbed lipid profile, insulin resistance and diabetes, explaining a substantial part of the total variance in total body fat (12% in young adult men, 15% in elderly men), the HOMA index (10%) and HDL cholesterol (7%). Conclusion: Our findings demonstrate that 17-glucuronidation of the DHT metabolite androstane-3alpha,17beta-diol is strongly associated with several metabolic risk factors in men. Future longitudinal studies are required to determine the possible impact of the 17G/DHT ratio as a metabolic risk factor in men.
|
|
