Co-expression of 1α-hydroxylase and vitamin D receptor in human articular chondrocytes.

BACKGROUND: The aim was to investigate whether resident chondrocytes in human articular cartilage and in subculture express vitamin D receptor (VDR) and the enzyme that hydroxylates the prohormone 25(OH)D3 to the active hormone 1α,25(OH)2D3, namely 1α-hydroxylase (CYP27B1). Any putative effects of vitamin D on chondrocytes were also explored. METHODS: Cartilage from human osteoarthritic knee joints, cultured chondrocytes and cells grown in 3D spheroids were examined for the expression of VDR and 1α-hydroxylase by PCR, Western blots and immunolabelling. Receptor engagement was judged by visualizing nuclear translocation. The effects of 25(OH)D3 and 1α,25(OH)2D3 on chondrocyte functions were assessed in proliferation-, chondrogenesis- and cartilage signature-gene expression assays. The capability of chondrocytes to hydroxylate 25(OH)D3 was determined by measuring the concentration of metabolites. Finally, a putative regulation of receptor and enzyme expression by 1α,25(OH)2D3 or interleukin (IL)-1ß, was investigated by Western blot. RESULTS: Gene expression was positive for VDR in freshly isolated cells from native cartilage, cells subcultured in monolayers and in spheroids, whereas protein expression, otherwise judged low, was apparent in monolayers. Nuclear translocation of VDR occurred upon 1α,25(OH)2D3 treatment. Transcripts for 1α-hydroxylase were detected in freshly isolated cells, cultured cells and spheroids. Western blots and immunolabelling detected 1α-hydroxylase protein in all materials, while staining of tissue appeared confined to cells at the superficial layer. A dose-dependent 1α,25(OH)2D3 production was measured when the enzyme substrate was supplied to cell cultures. Western blots revealed that the VDR, but not 1α-hydroxylase, was induced by IL-1ß treatment in adherent cells. Proliferation in monolayers was enhanced by both 25(OH)D3 and 1α,25(OH)2D3, and both compounds had negative effects on chondrogenesis and cartilage-matrix genes. CONCLUSIONS: VDR expression in resident cartilage chondrocytes, generally considered differentiated cells, is elusive. A similar pattern applies for redifferentiated chondrocytes in spheroid cultures, whereas dedifferentiated cells, established in monolayers, stably express VDR. Both 25(OH)D3 and 1α,25(OH)2D3 are able to potentiate cell proliferation but have a negative impact in proteoglycan synthesis. Chondrocytes express 1α-hydroxylase and may contribute to the production of 1α,25(OH)2D3 into the joint environment. Effects of vitamin D could be unfavourable in the context of cartilage matrix synthesis.

The role of formyl peptide receptor 1 (FPR1) in neuroblastoma tumorigenesis.

BACKGROUND: Formyl peptide receptor 1 (FPR1) is a G protein-coupled receptor mainly expressed by the cells of myeloid origin, where it mediates the innate immune response to bacterial formylated peptides. High expression of FPR1 has been detected in various cancers but the function of FPR1 in tumorigenesis is poorly understood. METHODS: Expression of FPR1 in neuroblastoma cell lines and primary tumors was studied using RT-PCR, western blotting, immunofluorescence and immunohistochemistry. Calcium mobilization assays and western blots with phospho-specific antibodies were used to assess the functional activity of FPR1 in neuroblastoma. The tumorigenic capacity of FPR1 was assessed by xenografting of neuroblastoma cells expressing inducible FPR1 shRNA, FPR1 cDNA or control shRNA in nude mice. RESULTS: FPR1 is expressed in neuroblastoma primary tumors and cell lines. High expression of FPR1 corresponds with high-risk disease and poor patient survival. Stimulation of FPR1 in neuroblastoma cells using fMLP, a selective FPR1 agonist, induced intracellular calcium mobilization and activation of MAPK/Erk, PI3K/Akt and P38-MAPK signal transduction pathways that were inhibited by using Cyclosporin H, a selective receptor antagonist for FPR1. shRNA knock-down of FPR1 in neuroblastoma cells conferred a delayed xenograft tumor development in nude mice, whereas an ectopic overexpression of FPR1 promoted augmented tumorigenesis in nude mice. CONCLUSION: Our data demonstrate that FPR1 is involved in neuroblastoma development and could represent a therapy option for the treatment of neuroblastoma.

Human articular chondrocytes express functional leukotriene B4 receptors.

Leukotriene B4 (LTB4) is a potent chemoattractant associated with the development of osteoarthritis (OA), while its receptors BLT1 and BLT2 have been found in synovium and subchondral bone. In this study, we have investigated whether these receptors are also expressed by human cartilage cells and their potential effects on cartilage cells. The expression of LTB4 receptors in native tissue and cultured cells was assessed by immunohistochemistry, immunocytochemistry, polymerase chain reaction (PCR) and electron microscopy. The functional significance of the LTB4 receptor expression was studied by Western blotting, using phospho-specific antibodies in the presence or absence of receptor antagonists. In further studies, the secretion of pro-inflammatory cytokines, growth factors and metalloproteinases by LTB4-stimulated chondrocytes was measured by multiplex protein assays. The effects of LTB4 in cartilage signature gene expression in cultured cells were assessed by quantitative PCR, whereas the LTB4-promoted matrix synthesis was determined using 3D pellet cultures. Both receptors were present in cultured chondrocytes, as was confirmed by immunolabelling and PCR. The relative quantification by PCR demonstrated a higher expression of the receptors in cells from healthy joints compared with OA cases. The stimulation of cultured chondrocytes with LTB4 resulted in a phosphorylation of downstream transcription factor Erk 1/2, which was reduced after blocking BLT1 signalling. No alteration in the secretion of cytokine and metalloproteinases was recorded after challenging cultured cells with LTB4; likewise, cartilage matrix gene expression and 3D tissue synthesis were unaffected. Chondrocytes express BLT1 and BLT2 receptors, and LTB4 activates the downstream Erk 1/2 pathway by engaging the high-affinity receptor BLT1. However, any putative role in cartilage biology could not be revealed, and remains to be clarified.

Serum free and bio-available 25-hydroxyvitamin D correlate better with bone density than serum total 25-hydroxyvitamin D.

In the circulation 25-hydroxyvitamin D (25(OH)D) is bound to vitamin D-binding protein (DBP) and albumin. Only a small fraction is in the unbound, free form. According to the 'free-hormone-hypothesis' only the free form is biologically active. Genetic differences in DBP may affect the binding to 25(OH)D and thereby the amount of free 25(OH)D. In the present study sera were obtained from 265 postmenopausal women with low bone mass density (BMD). Serum 25(OH)D, DBP and albumin were measured and the free and bio-available (free + albumin-bound) 25(OH)D calculated. Based on genotyping of the polymorphisms rs7041 and rs4588, the six common DBP phenotypes were identified and the free and bio-available 25(OH)D calculated according to the corresponding binding coefficients. Relations between measures of 25(OH)D and PTH and BMD were evaluated with linear regression adjusted for age and BMI. The calculated amount of free and bio-available 25(OH)D was 0.03% and 13.1%, respectively, of the measured total serum 25(OH)D. Adjusting for DBP phenotype affected the calculated free and bio-available 25(OH)D levels up to 37.5%. All measures of 25(OH)D correlated significantly with PTH, whereas a significant association with BMD was only seen for the free and bio-available 25(OH)D measures. Adjusting for the DBP phenotypes improved the associations. These relations were almost exclusively seen in subjects not using vitamin D and/or calcium supplements. In conclusion, the free and bio-available forms of 25(OH)D may be a more informative measure of vitamin D status than total 25(OH)D. Adjustment for DBP phenotype may improve this further.

Serum calcium and the calcium-sensing receptor polymorphism rs17251221 in relation to coronary heart disease, type 2 diabetes, cancer and mortality: the Tromsø Study.

Serum calcium measured in 27,158 subjects in 1994 and the calcium-sensing receptor polymorphism rs17251221 genotyped in 9,404 subjects were related to cardiovascular risk factors, incident myocardial infarction (MI), type 2 diabetes (T2DM), cancer and death during follow-up until 2008-2010. In a Cox regression model with adjustment for age, gender, smoking and body mass index, subjects with serum calcium 2.50-2.60 mmol/L had a significantly increased risk of incident MI [n = 1,802, hazards ratio (HR) 1.40, 95 % confidence interval (CI) 1.18, 1.66] and T2DM (n = 705, HR 1.49, 95 % CI 1.15, 1.94) and a significantly reduced risk of cancer (n = 2,222, HR 0.73, 95 % CI 0.62, 0.86) as compared to subjects with serum calcium 2.20-2.29 mmol/L. For rs17251221 there was a mean difference in serum calcium of 0.05 mmol/L between major and minor homozygote genotypes. No consistent, significant relation between rs17251221 and risk factors or the major hard endpoints were found. The minor homozygote genotype (high serum calcium) had a significant twofold increased risk (HR 2.32, 95 % CI 1.24, 4.36) for prostate cancer, as compared to the major homozygote. This may be clinically important if confirmed in other cohorts.

Effect of vitamin D supplement on depression scores in people with low levels of serum 25-hydroxyvitamin D: nested case-control study and randomised clinical trial.

AIMS: To compare depressive symptoms in participants with low and high serum 25-hydroxyvitamin D (25(OH)D) levels and to examine whether supplementation with vitamin D(3) would improve symptoms in those with low serum 25(OH)D levels. METHOD: Participants with low 25(OH)D levels were randomised to either placebo or 40 000 IU vitamin D(3) per week for 6 months. Individuals with high serum 25(OH)D levels were used as nested controls. Depressive symptoms were evaluated with the Beck Depression Inventory, Hospital Anxiety and Depression Scale, Seasonal Pattern Assessment Scale and Montgomery-Åsberg Depression Rating Scale. The study was registered at ClinicalTrials.gov (NCT00960232). RESULTS: Participants with low 25(OH)D levels (n = 230) at baseline were more depressed (P<0.05) than participants with high 25(OH)D levels (n = 114). In the intervention study no significant effect of high-dose vitamin D was found on depressive symptom scores when compared with placebo. CONCLUSIONS: Low levels of serum 25(OH)D are associated with depressive symptoms, but no effect was found with vitamin D supplementation.

100 YEARS OF VITAMIN D: Combined hormonal contraceptives and vitamin D metabolism in adolescent girls.

Objective: Combined hormonal contraceptive (CHC) use has been associated with higher total 25-hydroxyvitamin D (25(OH)D) levels. Here, we investigate the relation between CHC use and vitamin D metabolism to elucidate its clinical interpretation. Methods: The cross-sectional Fit Futures 1 included 1038 adolescents. Here, a subgroup of 182 girls with available 25(OH)D, 1,25-dihydroxyvitamin D (1,25(OH)2D), 24,25-dihydroxyvitamin D (24,25(OH)2D), vitamin D-binding protein (DBP) and measured free 25(OH)D levels, in addition to parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23), was investigated. Vitamin D metabolites were compared between girls using (CHC+) and not using CHC (CHC-). Further, the predictability of CHC on 25(OH)D levels was assessed in a multiple regression model including lifestyle factors. The ratios 1,25(OH)2D/25(OH)D and 24,25(OH)2D/25(OH)D (vitamin D metabolite ratio (VMR)) in relation to 25(OH)D were presented in scatterplots. Results: CHC+ (n = 64; 35% of the girls) had higher 25(OH)D levels (mean ± s.d., 60.3 ± 22.2) nmol/L) than CHC- (n = 118; 41.8 ± 19.3 nmol/L), P -values <0.01. The differences in 25(OH)D levels between CHC+ and CHC- were attenuated but remained significant after the adjustment of lifestyle factors. CHC+ also had higher levels of 1,25(OH)2D, 24,25(OH)2D, DBP and calcium than CHC-, whereas 1,25(OH)2D/25(OH)D, PTH, FGF23 and albumin were significantly lower. Free 25(OH)D and VMR did not statistically differ, and both ratios appeared similar in relation to 25(OH)D, irrespective of CHC status. Conclusion: This confirms a clinical impact of CHC on vitamin D levels in adolescents. Our observations are likely due to an increased DBP-concentration, whereas the free 25(OH)D appears unaltered.

Serum 25-hydroxyvitamin D levels are inversely associated with glycated haemoglobin (HbA(1c)). The Tromsø Study.

Animal and human studies have shown an association between serum 25-hydroxyvitamin D (25(OH)D) level and insulin secretion and sensitivity. Accordingly, an association between 25(OH)D and glycated haemoglobin (HbA(1c)) is to be expected, and this was tested for in the present study. The Tromsø Study is a longitudinal population-based study initiated in 1974. In the sixth Tromsø Study conducted in 2007-2008, 12,984 subjects aged 30-87 years attended. After exclusion of current smokers and subjects with diabetes, the dataset consisted of 8643 subjects available for the present analyses. The correlation between serum 25(OH)D and HbA(1c) was -0.07 (p < 0.001). This association remained significant in a multiple linear regression model after adjustment for covariates gender, age, month of blood sampling, body mass index (BMI), physical activity score, serum triglycerides (TG), serum calcium and haemoglobin, and persisted across categories of gender, age, BMI and TG. The association appears to be most pronounced in the oldest, the obese and in those with the highest TG levels. Seasonal variation was found both for serum 25(OH)D and HbA(1c) with highest serum 25(OH)D levels and lowest HbA(1c) levels during summer months. In conclusion, there is a significant inverse association between serum 25(OH)D and HbA(1c) after adjustment for known confounders. The association is most pronounced in subjects with risk factors for glucose intolerance/type 2 diabetes. In a sub-analysis on subjects with diabetes the association between serum 25(OH)D and HbA(1c) appeared even stronger with a difference in HbA(1c) of 0.48 % between the highest and lowest serum 25(OH)D quartiles.

Serum 25-hydroxyvitamin D levels in subjects with reduced glucose tolerance and type 2 diabetes - the Tromsø OGTT-study.

The relationships between vitamin D concentrations, hyperglycemia, and insulin resistance remain uncertain. During 2008 - 2010, an oral glucose tolerance test was performed in 3520 subjects from Tromsø, Norway. Serum 25-hydroxyvitamin D [25(OH)D] was measured in 1193 subjects with normal glucose tolerance, in 304 with isolated impaired fasting glucose, in 254 with isolated impaired glucose tolerance, in 139 with a combination of the two, and in 194 subjects with type 2 diabetes. Serum 25(OH)D did not differ between subjects with isolated impaired fasting glucose or impaired glucose tolerance, but was lower in all groups of deranged glucose metabolism as compared with normal subjects. These differences could not be explained by differences in intakes of vitamin D from cod liver oil or other supplements and remained statistically significant after adjustment for gender, age, body mass index, physical activity score, and month of examination. When the cohort was divided according to serum 25(OH)D quartiles, there was an improvement in all measures of glucose metabolism (fasting and 2-hour plasma glucose, serum insulin, HbA(1c)) and estimates of insulin resistance (QUICKI , HOMA-IR, ISI(0.120)) with increasing serum 25(OH)D quartile. However, interventional studies are needed to prove a causal relationship between vitamin D and glucose metabolism.

Tracking of serum 25-hydroxyvitamin D levels during 14 years in a population-based study and during 12 months in an intervention study.

Low serum 25-hydroxyvitamin D (25(OH)D) levels are associated with risk factors for cardiovascular disease, and they also appear to predict later development of type 2 diabetes, cancer, and an increased mortality rate. These predictions are all based on a single 25(OH)D measurement, but so far there are no known reports on tracking of serum 25(OH)D levels. In the present Norwegian study, serum 25(OH)D levels were measured 1) in 2,668 subjects in the 1994 and 2008 Tromsø surveys and 2) every third month for 1 year in 94 subjects randomly assigned to placebo in a vitamin D intervention study. There was a marked seasonal variation in 25(OH)D, and, depending on the method of adjusting for season, the correlation coefficient between serum 25(OH)D measurements from 1994 and 2008 ranged from 0.42 to 0.52. In the 1-year intervention study, the correlation between baseline and 12-month values was 0.80. Apart from the effect of season, changes in weight, intake of vitamin D, and physical activity were related to change in serum 25(OH)D levels. Tracking of serum 25(OH)D appears similar to that for blood pressure and serum lipids, and it provides some support for the use of a single 25(OH)D measurement to predict future health outcomes.

No effect of supplementation with cholecalciferol on cytokines and markers of inflammation in overweight and obese subjects.

Epidemiological studies indicate a relation between vitamin D status and autoimmune diseases, and in vitro studies demonstrate an effect of 1,25-dihydroxyvitamin D on immune activation. However, the relation between serum levels of 25-hydroxyvitamin D (25(OH)D) and the effect of vitamin D supplementation on serum levels of cytokines are not settled. In the present study interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, IL-13, IL-17, intercellular adhesion molecule-1, interferon-gamma, monocyte chemotactic protein-1, and high sensitivity C-reactive protein, were measured in 437 overweight subjects and 324 completed a one year intervention with 40,000 IU vitamin D per week (group DD), 20,000 IU vitamin D per week (group DP), or placebo (group PP). No consistent relations between serum levels of the cytokines and 25(OH)D were found at baseline. In the intervention study, there was no difference in delta values (value at end of study minus value at inclusion) between the three groups regarding the individual cytokines measured, nor was there any indication of a polarization of the T cells towards a Th2 dominant type. In conclusion, we were not able to demonstrate with certainty any significant relation between serum levels of 25(OH)D levels and a number of cytokines and markers of inflammation.

Cross-sectional and longitudinal relation between serum 25-hydroxyvitamin D and body mass index: the Tromsø study.

PURPOSE: The serum 25-hydroxyvitamin D (25(OH)D) levels are lower in obese than lean subjects. The present study examines the cross-sectional and longitudinal relations between body mass index (BMI) and serum 25(OH)D, and the serum 25(OH)D response to vitamin D supplementation in relation to BMI. METHODS: The Tromsø study is a longitudinal population-based multipurpose study. The fourth survey was conducted in 1994 and the sixth in 2008. The intervention study was a 1-year placebo-controlled randomized intervention trial, where the results from the 93 subjects given 40,000 IU per week are presented. RESULTS: A total of 10,229 subjects were included in the 2008 cross-sectional study. There was a significant negative association between serum 25(OH)D levels and BMI which was also present during the winter months. Serum 25(OH)D levels varied through seasons, but not BMI. In the longitudinal study from 1994 to 2008 which included 2,656 subjects, change in BMI was a significant negative predictor of change in 25(OH)D. In the intervention study, there was a significant and negative correlation between BMI and serum 25(OH)D both at baseline and at the end of the study. The increase in serum 25(OH)D after 1 year was significantly and inversely related to baseline BMI. CONCLUSIONS: We have confirmed the strong association between serum 25(OH)D and BMI. The very obese need higher vitamin D doses than lean subjects to achieve the same serum 25(OH)D levels.

No significant effect on bone mineral density by high doses of vitamin D3 given to overweight subjects for one year.

BACKGROUND: In meta-analyses supplementation with vitamin D appears to reduce incidence of fractures, and in cross-sectional studies there is a positive association between serum 25-hydroxyvitamin D (25(OH)D) levels and bone mineral density (BMD). However, the effect of supplementation with high doses of vitamin D on BMD is more uncertain and could in theory have both positive and negative effects. METHODS: The study was a one year, double blind placebo-controlled intervention trial performed at the University Hospital of North Norway. 421 subjects, 21 - 70 years old, were included and 312 completed the study. The subjects were randomized to vitamin D3 40.000 IU per week (DD group), vitamin D3 20.000 IU per week (DP group), or placebo (PP group). All subjects were given 500 mg calcium daily. Serum 25(OH)D, osteoprotegrin (OPG), receptoractivator of nuclear factor-kappaB ligand (RANKL), and BMD at the lumbar spine and the hip were measured before and at the end of the study. RESULTS: At baseline the mean serum 25(OH)D levels were 58 nmol/L (all subjects) and increased to 141 and 100 nmol/L in the DD and DP groups, respectively. After one year, no significant differences were found between the three groups regarding change in BMD, serum OPG or RANKL. CONCLUSIONS: Supplementation with high doses of vitamin D for one year does not appear to have a negative effect on BMD in healthy subjects. In order to disclose a positive effect, subjects with low BMD and/or low serum 25(OH)D levels need to be studied. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov (NCT00243256).

Supplementation with cholecalciferol does not improve glycaemic control in diabetic subjects with normal serum 25-hydroxyvitamin D levels.

BACKGROUND: Studies have suggested that vitamin D may be important for both insulin sensitivity and insulin secretion, and that supplementation with vitamin D may subsequently prevent development of type 2 diabetes. AIM OF THE STUDY: The objective of the current study was to test the hypothesis that supplementation with vitamin D would improve glycaemic control in subjects with type 2 diabetes. METHODS: Thirty-six subjects with type 2 diabetes, treated with metformin and bed-time insulin, were randomised to supplementation with cholecalciferol (40,000 IU per week) versus placebo for 6 months. Thirty-two subjects participated throughout the entirety of the study. Fasting blood samples were drawn before and at the end of the 6 month study without the previous bed-time insulin injection. The insulin and metformin doses were not changed throughout the study. RESULTS: After 6 months, the fasting glucose, insulin, C-peptide, fructosamine, and HbA(1c) levels were not significantly different from baseline values. In addition, changes in these parameters (values at 6 months minus values at baseline) did not differ between the vitamin D and the placebo group. CONCLUSIONS: We were not able to demonstrate that vitamin D supplementation had a significant effect on glucose metabolism in subjects with type 2 diabetes but without vitamin D deficiency. Further studies are needed in larger groups of subjects with type 2 diabetes or impaired glucose tolerance, who also exhibit low serum 25-hydroxyvitamin D levels.

Vitamin D supplementation has no effect on cognitive performance after four months in mid-aged and older subjects.

BACKGROUND: Low serum 25-hydroxyvitamin D (25(OH)D) levels are associated with impaired cognitive function, but the effect of vitamin D supplementation on cognitive function is uncertain. METHODS: 422 subjects were included in a randomized controlled trial with vitamin D (cholecalciferol) 100,000 IU given as a bolus dose followed by 20,000 IU per week versus placebo for four months. Cognitive function was evaluated with verbal recall test, coding test and tapping test. RESULTS: 374 subjects (mean age 52 years, 198 males) had complete cognitive tests both at baseline and at end of study. Mean baseline serum 25(OH)D level was 34 nmol/L. At baseline there were no significant associations between serum 25(OH)D and the three separate cognitive tests. At the end of the study mean serum 25(OH)D levels were 89 nmol/L and 31 nmol/L in the vitamin D and placebo groups, respectively. At the end of the study, there were no statistically significant differences between the two groups regarding change in the cognitive test scores. Nor did sub-group analyses based on gender, age, baseline serum 25(OH)D and cognitive test scores reveal significant differences between the two groups at the end of the study. CONCLUSIONS: Vitamin D supplementation did not improve cognitive function during a four months intervention in mid-aged and older subjects. TRIAL REGISTRATION: ClinicalTrials.govNCT02750293.

Cortisol levels and cognitive profile in major depression: A comparison of currently and previously depressed patients.

The association between depressive symptoms and elevated cortisol levels, and depression and cognitive functioning, has been less robust in outpatients with symptoms in the mild to moderate range. Furthermore, the association between elevated cortisol levels and cognitive functioning is unclear. In the present study, currently depressed (n = 37), previously depressed (n = 81) and never depressed controls (n = 50) were assessed on a range of neuropsychological measures. Salivary cortisol was measured in the morning and evening. Participants with current depression were non-hospitalized and had symptoms predominately in the mild to moderate range. Elevated salivary evening cortisol, but not morning cortisol, was significantly related to depressive symptoms. The difference in cortisol levels between the previously depressed group and the never depressed controls was not significant. The groups had significantly different cognitive profiles, with the currently depressed performing poorer on tasks related to working memory compared to the never depressed controls. Both the currently and previously depressed performed worse on attentional tasks. The findings indicate that outpatients with mild to moderate depression have elevated cortisol levels and limited mild cognitive impairments. Furthermore, mild impairments in attention may persist after remission, indicating that this could be a trait-marker in depression. The present study did not find support for a significant relationship between cortisol and cognitive functioning.

Hormone replacement therapy use and plasma levels of sex hormones in the Norwegian Women and Cancer postgenome cohort - a cross-sectional analysis.

BACKGROUND: Hormone replacement therapy use (HRT) is associated with increased breast cancer risk. Our primary objective was to explore hormone levels in plasma according to HRT use, body mass index (BMI) and menopausal status. A secondary objective was to validate self-reported questionnaire information on menstruation and HRT use in the Norwegian Women and Cancer postgenome cohort (NOWAC). METHODS: We conducted a cross-sectional study of sex hormone levels among 445 women aged 48-62 who answered an eight-page questionnaire in 2004 and agreed to donate a blood sample. The samples were drawn at the women's local general physician's offices in the spring of 2005 and sent by mail to NOWAC, Tromsø, together with a two-page questionnaire. Plasma levels of sex hormones and Sex Hormone Binding Globulin (SHBG) were measured by immunometry. 20 samples were excluded, leaving 425 hormone measurements. RESULTS: 20% of postmenopausal women were HRT users. The plasma levels of estradiol (E2) increased with an increased E2 dose, and use of systemic E2-containing HRT suppressed the level of Follicle Stimulating Hormone (FSH). SHBG levels increased mainly among users of oral E2 preparations. Vaginal E2 application did not influence hormone levels. There was no difference in BMI between HRT users and non-users. Increased BMI was associated with increased E2 and decreased FSH and SHBG levels among non-users. Menopausal status defined by the two-page questionnaire showed 92% sensitivity (95% CI 89-96%) and 73% specificity (95% CI 64-82%), while the eight-page questionnaire showed 88% sensitivity (95% CI 84-92%) and 87% specificity (95% CI 80-94%). Current HRT use showed 100% specificity and 88% of the HRT-users had plasma E2 levels above the 95% CI of non-users. CONCLUSION: Users of systemic E2-containing HRT preparations have plasma E2 and FSH levels comparable to premenopausal women. BMI has an influence on hormone levels among non-users. NOWAC questionnaires provide valid information on current HRT use and menopausal status among Norwegian women who are between 48 and 62 years old.

Failure to Find a Conditioned Placebo Analgesic Response.

Background: Associative learning has, in several studies, been modulated by the sex of the participant. Consistent with this, a recent review found that conditioned nocebo effects are stronger in females than in males. Purpose: It has been suggested that conditioned placebo responses are stronger in females, and this hypothesis was investigated in the present study. Cortisol and measures of negative emotions were taken to investigate if these processes could mediate any conditioned placebo effects. Methods: Cold pain was applied to the volar forearm. The Conditioned group received inert capsules prior to two presentations of less painful stimulations, to associate intake of the capsules with reduced pain. The pain control group received the same painful stimulation as the Conditioned group, but no capsules. The Capsule control group received the capsules in the same way as the Conditioned group, but no decrease in the painful stimulation. Participant sex was crossed across groups. It was hypothesized that in the Conditioned group, an expectation of reduced pain should be induced after administration of the capsules, and this should generate placebo analgesia, and mostly so in females. Results: The Conditioned group reported lower pain during conditioning, and rated the capsules as more effective painkillers than the capsule control group. However, placebo analgesia was not reliably observed in the Conditioned group. Conclusion: The placebo capsules were rated as effective painkillers, but this did not translate into a placebo analgesic effect. This could be due to violation of response expectancies, too few conditioning trials, and differences in pain ratings in the pre-test that could be due to previous experience with painkillers.

Thyroid stimulating hormone and left ventricular function.

CONTEXT: Overt hypo- and hyperthyroidism are associated with cardiac disease, whereas this relation is more uncertain regarding subclinical thyroid dysfunction. OBJECTIVE: The objective was to assess the relation between serum TSH level and cardiac function. DESIGN: We conducted a cross-sectional epidemiological study and a nested case-control study. SETTING: The study was performed at a university hospital. SUBJECTS: A total of 2035 subjects were included in the epidemiological study and 204 subjects in the nested case-control study (serum TSH < 0.50, 0.50-3.49, and 3.50-10.0 mIU/liter in 20, 118, and 66 subjects, respectively, all with normal serum free T(4) and free T(3) levels). MAIN OUTCOME MEASURES: Left ventricular mass by body surface area (LVMI) and indices of left ventricular function, as assessed by conventional and pulsed-wave tissue Doppler (PWTD) echocardiography, were recorded. RESULTS: No significant relation was found between serum TSH level and LVMI. In the nested case-control study, the subjects with serum TSH 3.50-10.0 mIU/liter had no signs of cardiac dysfunction. However, the PWTD data showed higher velocities at all measurement sites in the subjects with serum TSH less than 0.50 mIU/liter as compared with the euthyroid group. CONCLUSIONS: With the possible exception of overt hypo- and hyperthyroidism, there is no significant association between serum TSH level and LVMI. Subjects with subclinical hypothyroidism, in whom the mean serum TSH level is slightly above the reference range, appear to have normal cardiac function, whereas subjects with serum TSH levels less than 0.5 mIU/liter appear to have changes in myocardial velocities detected by PWTD.

Serum levels of vitamin D and haemostatic factors in healthy subjects: the Tromsø study.

BACKGROUND: Receptors for vitamin D have been found in various tissues, including the vascular endothelium. The role of vitamin D in the haemostatic process is uncertain, but in vitro studies may indicate a pro-fibrinolytic effect. METHODS: Two hundred and six subjects (105 males) were included in the study. The relations between indices of calcium metabolism and haemostatic factors [tissue plasminogen activator antigen (tPA Ag), plasminogen activator inhibitor 1 (PAI-1), prothrombin fragment 1+2, activated factor VII and total factor VII coagulant activity] and high-sensitivity C-reactive protein (HS-CRP) were examined. RESULTS: There were significant and negative correlations between serum 25(OH) vitamin D and PAI-1 and tPA Ag, and between serum 1,25(OH)2 vitamin D and tPA Ag and HS-CRP. In a multiple linear regression model with age, gender, body mass index and smoking status as covariables, only the relation between 25(OH) vitamin D and tPA Ag was significant. There were no significant relations between any of the haemostatic factors tested and serum parathyroid hormone. CONCLUSION: It appears that the serum level of vitamin D is related to fibrinolytic activity and to the integrity of the vascular endothelium, but the clinical importance of this observation remains to be determined.