Tissue mRNA expression of the glucocorticoid receptor and its splice variants in fatal critical illness

Background Critical illness results in activation of the hypothalamic–pituitary–adrenal (HPA) axis, which might be accompanied by a peripheral adaptation in glucocorticoid sensitivity. Tissue sensitivity is determined by the active glucocorticoid receptor GRα, of which two splice variants involving the hormone‐binding domain exist, GRβ and GR‐P. Objective To study tissue mRNA expression of the GR and its splice variants in fatal critical illness. Design and methods We assessed mRNA expression of the GRα, GRβ and GR‐P variants in liver (n = 58) and muscle (n = 65) of patients who had died after intensive care, and had been randomized for insulin treatment. We analysed whether GR mRNA expression was associated with insulin treatment, cortisol levels and glucocorticoid treatment. Results GRα and GR‐P mRNA constituted 87 ± 8% and 13 ± 2%, respectively, of total GR mRNA in liver. GRβ mRNA could only be amplified in five liver samples. All variants were present in most muscle samples (α = 96 ± 11%, P = 3·9 ± 0·4%, β = 0·010 ± 0·002%). GR expression was not associated with insulin therapy. A strong positive relationship was observed between the different GR variants in both liver and muscle (P < 0·001 for all). Serum cortisol levels were negatively associated with liver GRα and muscle GR‐P expression (P < 0·05). mRNA expression of both liver GRα and GR‐P, but not muscle GR, was substantially lower in patients who had received exogenous glucocorticoids (P < 0·01). Conclusion We demonstrate the presence of GRα and GR‐P mRNA in liver and of GRα, GRβ and GR‐P mRNA in muscle, with no evidence for altered splicing in critical illness. In contrast to muscle GR, liver GR expression was substantially lower in patients receiving exogenous glucocorticoids.     

Does partial surgical tumour removal influence the response to octreotide‐LAR in acromegalic patients previously resistant to the somatostatin analogue?

Objective To compare the intrapatient response to the same dose of slow‐release octreotide (OCT‐LAR) before and after noncurative surgery in acromegalic patients who did not attain disease control after primary treatment with OCT‐LAR. Design Prospective clinical study. Patients Eleven acromegalic patients (eight men, aged 42·45 ± 11·15 years, 10 macroadenomas) received OCT‐LAR (20 mg, n = 1; 30 mg, n = 10) every 28 days as the primary treatment (1stOCT‐LAR) for 11·3 ± 4·2 months, without IGF‐I normalization. They were subsequently submitted to surgery without cure and were then treated with the same dose of OCT‐LAR for 8·0 ± 6·5 months (2ndOCT‐LAR). Measurements GH and IGF‐I serum concentrations were obtained under basal conditions as well as during treatment. Pituitary tumour volume was assessed by magnetic resonance imaging (MRI) of the sella. IGF‐I was also expressed as a percentage of the upper limit of the normal age‐ and sex‐matched range (%ULNR IGF‐I). Results After 1stOCT‐LAR, there was a decrease in GH levels (P = 0·003) and %ULNR IGF‐I (P = 0·009) compared to baseline (B), but no IGF‐I normalization. Tumour shrinkage was observed in eight of 10 patients with macroadenomas (median 63·7%, range 24·5–75·5%). After surgery, mean levels of GH and %ULNR IGF‐I were lower than those at baseline (P = 0·0004 and P = 0·003, respectively), but not when compared to values during 1stOCT‐LAR (P = 1·000 and P = 0·957, respectively). MRI confirmed surgical tumour removal (median 64%, range 4·9–96·6%) in eight of the 10 patients. Comparing the 2ndOCT‐LAR results with postsurgical results, there were no significant decrease in %ULNR IGF‐I (P = 0·061) and GH levels (P = 0·414). Nine patients (82%) achieved IGF‐I normalization. The degree of surgical tumour reduction did not correlate with IGF‐I normalization (P = 0·794). When comparing the results between 1stOCT‐LAR and 2ndOCT‐LAR, there was a decrease, albeit not statistically significant, in serum GH levels (P = 0·059) and a significant decrease in %ULNR IGF‐I (P = 0·011). Conclusions Using strict criteria (same patient, same drug, same dose) our results strongly suggest that the surgical reduction of tumour mass can improve the outcome of OCT‐LAR treatment in acromegalic patients resistant to primary therapy with SA.     

Relationship between ghrelin and the metabolic syndrome in the elderly: a longitudinal population-based study

Context Ghrelin regulates energy homeostasis and may contribute to the development of the metabolic syndrome (MS) in the elderly. Objective To study the relationship between ghrelin and the MS, IGF‐I and life style factors over a 2‐year follow‐up. Design Longitudinal population‐based study, starting from 2002; 2 years follow‐up. Participants Three hundred and thirteen (153 men/160 women) individuals living independently older than 70 years. Results MS was found in 54·9% of men and 61% of women. In the 229 subjects available at follow‐up, ghrelin was higher in men than in women at basal (P = 0·002) and 2‐year follow‐up (P = 0·004). Ghrelin decreased over time in both genders (P < 0·01). Ghrelin was lower in individuals showing MS compared to non‐MS (P = 0·08), but this difference was more evident at 2‐year follow‐up (P = 0·016), mostly due to men with MS (P = 0·002) and even after adjustment for BMI, gender and age. Individuals with MS had an OR of 1·67 (95% CI: 1·0–2·78) for low ghrelin (< first tertile); when adjusting by BMI, gender and age, only high triglycerides with OR 1·8 (1·0–3·3), remained statistically significant among the MS components. IGF‐I showed a positive correlation with ghrelin only in individuals without MS (r_s 0·403, P < 0·001) with no gender differences; this relationship was not found in MS (r_s 0·120, P = 0·129). A positive association of ghrelin was found with academic level, alcohol consumption and smoking. Conclusions Ghrelin is higher in old men in comparison to women and decreases over time with a steeper decline in subjects with MS; moreover, in these subjects ghrelin/IGF‐I correlation is lost.     

Bone mineral density and bone turnover in Romanian children and young adults with classical 21-hydroxylase deficiency are influenced by glucocorticoid replacement therapy

Objective It remains controversial if glucocorticoid replacement therapy impairs bone mineral density (BMD) in young patients with 21‐hydroxylase deficiency. We aimed to analyze the impact of treatment variables, phenotype and genotype on BMD and bone metabolism in these patients. Design Cross‐sectional study. Measurements Twenty‐eight Caucasian patients with classical 21‐hydroxylase deficiency (5–39 years). Clinical parameters, hormonal status, osteocalcin (OC), C‐terminal telopeptide of type I collagen (CTX), genotype and lumbar BMD (Z‐scores) were assessed. Cumulative and mean hydrocortisone equivalent doses were calculated for the entire treatment period. Results Patients with severely reduced BMD Z‐scores (≤–2·5 SD) had significantly higher mean/cumulative glucocorticoid doses compared to patients with moderately reduced (P = 0·003/P = 0·026) and normal Z‐scores (> –1 SD) (P = 0·005/P = 0·011). Mean hydrocortisone equivalent doses > 20 mg/m²/day led to significantly lower lumbar BMD Z‐scores (–2·16 ± 1·4 SD) vs. doses ≤ 20 mg/m²/day (–0·59 ± 1·25 SD) (P = 0·008). BMD correlated negatively with mean/cumulative glucocorticoid doses and treatment duration. OC (86·45 ± 37·45 ng/ml) and CTX (1·45 ± 0·43 ng/ml) were significantly increased compared to an age‐ and sex‐matched control group in patients with active growth; only CTX was slightly increased in patients who completed growth. Conclusions High cumulative and mean glucocorticoid doses negatively impact on BMD in children and young adults with classical 21‐hydroxylase deficiency. Substitution therapy should be adapted particularly at this life period to prevent bone loss.     

GH and IGF-I deficiency are associated with reduced loss of fat mass after laparoscopic-adjustable silicone gastric banding

Context GH secretion is reduced in obese subjects and increases after body weight loss. It is still unclear if changes in the GH/IGF‐I axis after laparoscopic‐adjustable silicone gastric banding (LASGB) are associated with changes of body composition. Objective To analyse the relationships between changes in the GH/IGF‐I axis and those of body weight and composition before and after LASGB. Design Observational, prospective. Setting University ‘Federico II’ of Naples (Italy). Patients Seventy‐two severely obese females (BMI: 44·9 ± 4·68; mean age: 33·1 ± 11·34 years) were studied. Main outcome measures GH peak after GHRH plus arginine test, IGF‐I, IGFBP‐3 and ALS levels, fat mass (FM) and free fat mass (FFM) (by Bioelectrical Impedance Analysis) at baseline and 6 months after LASGB. The change in percentage of individual variables was calculated as well as that of excess of body weight loss (EBWL%). The FM%, FFM% and EBWL% were correlated with peak GH and IGF‐I levels changes. Results At baseline, GH deficiency (GHD) (GH peak = 4·1 µg/l) was found in 22 patients (31%), 16 of them also had IGF‐I deficiency (< –2SDS). IGF‐I levels were inversely correlated with waist circumference (r = –0·72, P < 0·001) and FM% (r = –0·75, P < 0·001). Post‐LASGB the patients were classified as follows: group (1) GH and IGF‐I sufficient (n = 44; 61·1%); group (2) GH and IGF‐I deficient (n = 14; 19·4%) and group (3) GH sufficient and IGF‐I deficient (n = 14; 19·4%). The percentage changes of EWBL (P < 0·05, P = 0·051, respectively) and FM (P < 0·001, P < 0·01, respectively) were lower in groups (2) and (3) than in group (1). At the stepwise linear regression analysis, postoperative IGF‐I levels were the strongest determinant of percent changes of FM (P < 0·0001), of FFM (P = 0·009) and of EBWL (P < 0·0001). Conclusions IGF‐I levels is the most sensitive to unfavourable changes in body composition 6 months after LASGB making investigation of the somatotropic axis useful in the evaluation of bariatric surgery outcomes.     

Influence of ethnicity on IGF-I and procollagen III peptide (P-III-P) in elite athletes and its effect on the ability to detect GH abuse

Context A method based on the two GH dependent markers, IGF‐I and procollagen III peptide (P‐III‐P) has been proposed to detect exogenously administered GH. As previous studies involved predominantly white European elite athletes, it is necessary to validate the method in other ethnic groups. Objective To examine serum IGF‐I and P‐III‐P in elite athletes of different ethnicities within 2 h of competing at national or international events. Design Cross‐sectional observational study. Setting National and International sporting events. Subjects 1085 elite athletes of different ethnicities. Intervention Serum IGF‐I and P‐III‐P were measured and GH‐2000 discriminant function score was calculated. Effect of ethnicity was assessed. Results In men, IGF‐I was 21·7 ± 2·6% lower in Afro‐Caribbeans than white Europeans (P < 0·0001) but there were no differences between other ethnic groups. In women, IGF‐I was 14·2 ± 5·1% lower in Afro‐Caribbeans (P = 0·005) and 15·6 ± 7·0% higher in Orientals (P = 0·02) compared with white Europeans. P‐III‐P was 15·2 ± 3·5%, 26·6 ± 6·6% and 19·3 ± 5·8% lower in Afro‐Caribbean (P < 0·0001), Indo‐Asian (P < 0·0001) and Oriental men (P = 0·001), respectively, compared with white European men. In women, P‐III‐P was 15·7 ± 4·7% lower in Afro‐Caribbeans compared to white Europeans (P =0·0009) but there were no differences between other ethnicities. Despite these differences, most observations were below the upper 99% prediction limits derived from white European athletes. All GH‐2000 scores lay below the cut‐off limit proposed for doping. Conclusions The GH‐2000 detection method based on IGF‐I and P‐III‐P would be valid in all ethnic groups.     

Inflammatory markers and visceral fat are inversely associated with maximal oxygen consumption in women with polycystic ovary syndrome (PCOS)

Background We investigated whether several different inflammatory markers including C‐reactive protein (CRP) and fibrinogen and white blood cells (WBCs) count, are associated with maximal oxygen consumption (VO_2max) in women with polycystic ovary syndrome (PCOS). Methods In PCOS women (n = 124, 24·1 ± 4·5 year‐old) VO_2max was measured during symptom‐limited cardiopulmonary exercise test. Abdominal fat distribution was determined by ultrasound. Physical activity level was assessed by a standardized questionnaire. CRP was measured by immunoassays, fibrinogen by the Clauss method, and WBCs count with a Coulter counter. Results Pearson's analysis showed a significant correlation between VO_2max and logCRP (r = –0·437, P < 0·001), fibrinogen (r = –0·479, P < 0·001), and WBCs count (r = –0·438, P < 0·001). Multivariable logistic regression model showed that age (β = –0·127, P = 0·005), AUC_INS (β = –0·335, P < 0·001), HDL‐C (β = 0·390, P < 0·001), physical activity score (β = 0·238, P = 0·002), visceral fat (β =–0·184), P = 0·023), FAI (β = –0·291, P = 0·028); CRP (β = –0·216, P = 0·011), fibrinogen (β = –0·113, P = 0·008) and WBCs count (β = –0·177, P < 0·001) were significantly associated with VO_2max. Conclusions Acute‐phase reactants, such as CRP and fibrinogen, and WBCs count were independently and inversely associated with a direct measure of cardiorespiratory fitness (VO_2max) in women with PCOS, even after adjustment for physical activity level and other potential confounding factors. These findings add to the growing body of evidence linking inflammation to cardiorespiratory fitness in PCOS women.     

Insulin resistance and body composition in preterm born children during prepubertal ages

Background Premature born children may show insulin resistance in childhood which may be due to intrauterine or postnatal adverse environmental factors. Objective Aim of this study was to evaluate insulin resistance and body composition in preterm born children born appropriate for gestational age (AGA) or small for gestational age (SGA) and relations with IGF‐I, IGFBP‐3 axis. Methods Ninety‐three preterm born children grouped as premature SGA (n = 30) and premature AGA (n = 63) were evaluated at age 4·6 ± 0·2 years and 4·7 ± 0·1 years with respect to their glucose, insulin, IGF‐I, IGFBP‐3, IGFBP‐1, leptin levels and body composition by dual‐energy X‐ray absorptiometry. Their data were compared to that of body mass index (BMI) matched term SGA (n = 42) and term AGA (n = 44) children of age 4·5 ± 0·2 and 3·8 ± 0·1 years. All children had height appropriate for their target height. Insulin resistance was evaluated by basal insulin and homeostasis model assessment for insulin resistance (HOMA‐IR). Results Basal insulin level was similar in preterm AGA (4·3 ± 1·4 pmol/l) and term AGA (7·9 ± 6·4 pmol/l) children at similar and normal BMI levels. Preterm SGA children had insulin levels (5·0 ± 3·6 pmol/l) similar to preterm AGA children but significantly lower than that in term SGA children (23·7 ± 20·8 pmol/l) (P = 0·001). Similar results were obtained for HOMA‐IR. Term SGA children had also significantly lower IGFBP‐1 levels. Body composition, leptin and IGFBP‐3 did not differ between the respective groups. IGF‐I was lower in preterm AGA (5·0 ± 0·6 nmol/l) than in term AGA (8·3 ± 1·2 nmol/l) (P < 0·001) children. Conclusions Premature born AGA and SGA children do not have insulin resistance when compared to term children if they have made a catch‐up growth appropriate for their target height and have normal BMI. The similar insulin levels in preterm SGA and preterm AGA children together with increased insulin levels in term SGA children points to the fact that it is the intrauterine restriction in the third trimester that has an adverse effect on future adverse metabolic outcome.     

Eugonadal male patients with adrenal incidentalomas and subclinical hypercortisolism have increased rate of vertebral fractures

Objective Subclinical hypercortisolism (SH) is suggested to exert a deleterious effect on bone. This effect and the role of gonadal status in male subjects are not fully elucidated. We evaluated bone mineral density (BMD) and prevalence of vertebral fractures in eugonadal male subjects with adrenal incidentalomas (AI) and without SH. Design This 12‐month observational multicentre study was performed between January and December 2006 on inpatient basis in three referral Italian centres. Patients Eighty‐eight consecutive eugonadal male patients with AI and 90 matched control subjects were studied. Measurements All subjects underwent the determination of BMD by dual‐energy X‐ray absorptiometry at lumbar spine (LS) and femoral neck (FN), and spinal radiograph. In AI patients SH was diagnosed in the presence of two of the following: urinary free cortisol > 193·1 nmol/l, cortisol after 1 mg dexamethasone suppression test > 82·8 nmol/l, ACTH levels < 2·2 pmol/l. Results As compared to patients without SH (SH–, n = 66) and controls, patients with SH (SH+, n = 22) had lower BMD at LS (Z‐score: SH+, –1·04 ± 1·84; SH–, 0·19 ± 1·34, Controls 0·20 ± 1·28, P = 0·001 and FN (Z‐score: SH+, –0·63 ± 1·01; SH–, 0·01 ± 1·01, Controls 0·26 ± 1·06, P = 0·002) and higher prevalence of fractures (SH+, 72·7%; SH–, 21·2%, Controls 20·0%, P = 0·0001). Multivariable analyses showed that SH was associated to BMD at LS (β = –0·378, P = 0·0001) and vertebral fractures (OR = 7·81, 95% CI 1·96–31·17, P = 0·004). Conclusion In eugonadal male patients with AI, SH is associated with low BMD and high prevalence of vertebral fractures.     

Serum B-cell maturation antigen is elevated in multiple myeloma and correlates with disease status and survival

Although TNFRSF17 (also designated as B‐cell maturation antigen (BCMA)) is expressed on tumour cells in B‐cell malignancies, it has not been found in serum. The present study found that BCMA concentrations were higher in the supernatants of cultured bone marrow mononuclear cells from multiple myeloma (MM) patients than in healthy subjects. Serum BCMA levels were measured in samples from MM patients (n = 209), monoclonal gammopathy of undetermined significance (MGUS) individuals (n = 23) and age‐matched controls (n = 40). BCMA was detected in the serum of untreated MM patients (n = 50) and levels were higher than in MGUS patients (P = 0·0157) and healthy subjects (P < 0·0001). Serum BCMA levels were higher among patients with progressive disease (n = 80) compared to those with responsive disease (n = 79; P = 0·0038). Among all MM patients, overall survival was shorter among patients whose serum BCMA levels were above the median (P = 0·001). We also demonstrated that sera from mice with human MM xenografts contained human BCMA, and levels correlated with the change in tumour volume in response to melphalan or cyclophosphamide with bortezomib. These results suggest that serum BCMA levels may be a new biomarker for monitoring disease status and overall survival of MM patients.     

Pre-gravid physical activity and reduced risk of glucose intolerance in pregnancy: the role of insulin sensitivity

Objective Pre‐gravid physical activity has been associated with a reduced risk of gestational diabetes mellitus (GDM), although neither the types of exercise nor the physiologic mechanisms underlying this protective effect have been well‐studied. Thus, we sought to study the relationships between types of pre‐gravid physical activity and metabolic parameters in pregnancy, including glucose tolerance, insulin sensitivity and β‐cell function. Design/patients/measurements A total of 851 women underwent a glucose challenge test (GCT) and a 3‐h oral glucose tolerance test (OGTT) in late pregnancy, yielding four glucose tolerance groups: (i) GDM; (ii) gestational impaired glucose tolerance (GIGT); (iii) abnormal GCT with normal glucose tolerance on OGTT (abnormal GCT NGT); and (iv) normal GCT with NGT on OGTT (normal GCT NGT). Pre‐gravid physical activity was assessed using the Baecke questionnaire, which measures (i) total physical activity and (ii) its three component domains: work, nonsport leisure‐time, and vigorous/sports activity. Results Glucose tolerance status improved across increasing quartiles of pre‐gravid total physical activity (P = 0·0244). Whereas neither work nor nonsport leisure‐time activity differed between glucose tolerance groups, pre‐gravid vigorous/sports activity was significantly higher in women with normal GCT NGT compared to women with (i) abnormal GCT NGT (P = 0·0018) (ii) GIGT (P = 0·0025), and (iii) GDM (P = 0·0044). In particular, vigorous/sports activity correlated with insulin sensitivity (measured by IS_OGTT) (r = 0·21, P < 0·0001). Furthermore, on multiple linear regression analysis, pre‐gravid vigorous/sports activity emerged as a significant independent predictor of IS_OGTT in pregnancy (t = 4·97, P < 0·0001). Conclusions Pre‐gravid vigorous/sports activity is associated with a reduced risk of glucose intolerance in pregnancy, an effect likely mediated by enhanced insulin sensitivity.     

Glucocorticoid replacement is associated with hypertriglyceridaemia, elevated glucose and higher non-HDL cholesterol and may diminish the association of HDL cholesterol with the -629C>A CETP promoter polymorphism in GH-receiving hypopituitary patients

Objectives The effect of glucocorticoid substitution on the prevalence of metabolic syndrome components (NCEP ATP III criteria) and serum lipid levels was determined in GH‐replaced hypopituitary patients. As glucocorticoid replacement is associated with a pronounced decrease in plasma cholesteryl ester transfer protein (CETP) activity, we also tested associations of HDL cholesterol with the –629C>A CETP promoter polymorphism in subjects with and without ACTH deficiency. Design and patients In a university setting, we retrieved protocolized clinical and laboratory data from 165 adult hypopituitary patients, who had received GH for 1 year. Results After adjustment for age, sex and smoking, non‐HDL cholesterol (P = 0·05) and triglycerides (P = 0·004) were higher, but HDL cholesterol was not decreased in 117 glucocorticoid (mainly cortisone acetate in two divided doses) receiving subjects compared to 48 ACTH‐sufficient subjects. The prevalence of elevated plasma glucose and/or diabetes (P = 0·04) and hypertriglyceridaemia (P = 0·005), but not of other metabolic syndrome components, was higher in glucocorticoid‐replaced subjects. HDL cholesterol was higher in –629 A allele carriers compared to –629CC homozygotes in ACTH‐sufficient subjects (P = 0·04), but not in glucocorticoid‐treated subjects (P = 0·13). Multiple linear regression analysis demonstrated that only in ACTH‐sufficient subjects, HDL cholesterol was independently related to this CETP gene variation (P = 0·03). Conclusions In GH‐ and glucocorticoid‐replaced hypopituitary patients, serum non‐HDL cholesterol and triglycerides are higher and the prevalence of hyperglycaemia is increased, but HDL cholesterol is not decreased. Conventional glucocorticoid replacement appears to diminish the association of HDL cholesterol with a common CETP gene variation.     

Concentrations of the acute phase reactants high-sensitive C-reactive protein and YKL-40 and of interleukin-6 before and after treatment in patients with acromegaly and growth hormone deficiency

Background Acromegaly is accompanied by increased cardiovascular mortality and a cluster of proatherogenic risk factors. In the general population, ischaemic heart disease (IHD) is associated with elevated levels of inflammatory markers. The acute phase reactant (APR) C‐reactive protein (CRP) has been reported to be reduced in acromegaly and increase after treatment, suggesting that excess of GH/IGF‐I could have anti‐inflammatory effects. This is in accordance with results obtained in patients with growth hormone deficiency (GHD), where increased levels of CRP have been reported. Objective To investigate the hypothesis that the GH/IGF‐I system is a suppressive regulator of inflammatory processes. Subjects and methods Twenty‐one acromegalic patients and 19 GH‐deficient patients were studied. The two APRs CRP and YKL‐40 and the proinflammatory cytokine interleukin‐6 (IL‐6) were measured before and after treatment and in healthy matched controls. Results In acromegalic patients, serum concentrations of high‐sensitive CRP (hsCRP) and YKL‐40 were reduced compared to controls (P < 0·001) and increased (P < 0·001) after treatment, together with IL‐6 (P = 0·021), to levels comparable with controls. Pretreatment serum YKL‐40 and IL‐6 showed a significant inverse correlation with IGF‐I and GH. In GH‐deficient patients, hsCRP and YKL‐40 were elevated compared to controls (P = 0·001 and P = 0·048). During treatment, levels of both APRs showed a trend towards a decrease (P = 0·087 and P = 0·060), and after treatment, levels of YKL‐40 no longer differed from that of controls. Serum IL‐6 was not different from controls and did not change during GH treatment. Conclusion The results point to the possibility of a relationship between GH disturbances and inflammatory processes.     

Seasonal variation in serum concentrations of reproductive hormones and urinary excretion of 6-sulfatoxymelatonin in men living north and south of the Arctic Circle: a longitudinal study

Objective Seasonal variation in photoperiod or temperature may influence human reproductive biology. The present study evaluated whether seasonal changes occurred in the levels of reproductive hormones and the major melatonin metabolite, 6‐sulfatoxymelatonin (aMT6s), in populations exposed to extreme variation in photoperiod and temperature. Design Two separate cohorts of Norwegian men were recruited from the general population in either of two locations: Tromsø (69·5°N, n = 92) or Oslo (60°N, n = 112), located north and south of the Arctic Circle (66·5°N), respectively. Measurements Four blood and 12‐h overnight urine samples were obtained on separate occasions over a 12‐month period, including during the photoperiod maximum and minimum. Serum concentrations of FSH, LH, testosterone (T), oestradiol (E₂), SHBG and the urinary excretion of aMT6s were assessed. Results Statistical analysis using generalized estimating equations indicated that LH levels were lowest during early winter in both locations (both P = 0·01). In Tromsø, free T and E₂ concentrations peaked during early winter (P = 0·02 and 0·003, respectively). In Oslo, free T levels were lowest during early winter (P = 0·06) whereas E₂ levels were lowest during late summer (P < 0·001). Urinary aMT6s concentrations were lowest during early summer in Tromsø and Oslo. Concentrations peaked during early winter in Tromsø (P < 0·001) and during late winter in Oslo (P < 0·001). Conclusions LH levels exhibited similar changes in both locations, whereas the patterns of changes of the sex steroid concentrations differed, possibly indicating different underlying mechanisms. Excretion of aMT6s was lowest during early summer in both locations, indicating that the long natural photoperiod was sufficient to cause suppression of melatonin secretion. Whether these changes have any biological significance remains uncertain.     

Effect of progestins with different glucocorticoid activity on bone metabolism

Objective Progestins are commonly prescribed for hormone replacement therapy (HRT) and contraception. However, the effects of progestins on bone metabolism remain unclear and are often controversial. Design and patients This study was conducted to test the hypothesis that progestins with no significant glucocorticoid activity may be a better choice for HRT to achieve increased beneficial effects on bone metabolism than progestins with strong glucocorticoid activity. A total of 104 postmenopausal women aged 50–75 years with osteoporosis were allocated randomly to three groups: (1) conjugated oestrogen plus medroxyprogesterone acetate (HRT‐MPA, with significant glucocorticoid activity); (2) conjugated oestrogen plus norethisterone (HRT‐NET, with no significant glucocorticoid activity); and (3) control (no treatment). Measurements Vertebral X‐rays and bone mineral density (BMD) at distal 1/3 radius were assessed at baseline and every 6 months during the 2‐year study period, along with markers of bone turnover. The occurrence of new nonvertebral fractures was identified by X‐ray. Results After the 2‐year treatment, mean BMD changes relative to baseline in the HRT‐MPA, HRT‐NET and control groups were 1·6%, 2·3% and –1·9%, respectively. In addition, the rate of increase in HRT‐NET was significantly greater than that in HRT‐MPA (P = 0·019). The incidence of new fractures during the 2‐year treatment in the control group was 26% (9/34). HRT‐NET treatment significantly inhibited the occurrence of new fractures (RR 0·14, 95% CI 0·02–0·93, P = 0·04), while HRT‐MPA treatment failed to show a statistically significant reduction (RR 0·41, 95% CI 0·14–1·24, P = 0·11). Both HRT‐MPA and HRT‐NET treatments significantly decreased serum osteocalcin levels by 29·4% and 23·5%, respectively, after 6 months of treatment, with the decrease in HRT‐MPA being significantly greater than that in HRT‐NET (P = 0·042). Conclusions These findings suggest that progestins with no significant glucocorticoid activity may be a better choice for HRT, resulting in increased beneficial effects on bone metabolism compared with progestins with strong glucocorticoid activity.     

The relationship between gonadotrophins, gonadal hormones and bone mass in men

Objective Inhibin A and B (Inh A and B), activin A (Act A) as well as FSH may play an important role in bone turnover in perimenopausal women. Data in men are lacking. The aim was to investigate the relationship between circulating concentrations of Inh B and Act A and FSH/LH/testosterone (T) and their contribution to bone mineral density (BMD) in a male population. Design and subjects Cross‐sectional case‐control study of 156 men, 63 with osteoporosis and 93 controls, aged (mean [SD]) 57·7 [13·7] years. Measurements Areal (aBMD) was measured at the femoral neck, total hip and lumbar spine. Volumetric BMD (vBMD) was calculated at the femoral neck and lumbar spine. Risk factors were assessed including the measurement of LH/FSH/T, Inh B and Act A. Results After correction for age and body mass index (BMI), associations were found between Inh B and FSH (beta regression coefficient β = ?0·326; P < 0·0001), T (β = ?0·36; P = 0·019) and Act A (β = ?0·4; P = 0·007) and between Inh B and LH (β = 0·23; P < 0·0001) in all patients. The controls had higher Inh B concentrations compared to the cases (Inh B: controls: 139 [86] pg/ml vs. cases 88 [51] pg/ml; P = 0·005). Act A tended to be lower in the controls (Act A: controls 0·63 [0·24] ng/ml vs. cases 0·75 [0·4] ng/ml; P = 0·056). Univariate regression analyses showed a positive association between Inh B and BMD (P < 0·01) at the lumbar spine and total hip. In contrast a negative association was seen between FSH and BMD at the lumbar spine and femoral neck (P < 0·01). In a partial multivariate regression model that included the gonadal factors only, a positive association was seen between Inh B and BMD at the hip (β = 0·088; P = 0·04). When all hormones including the gonadotrophins were entered in a full multivariate model, FSH and LH were found to be better predictors of BMD than Inh B or Act A in the controls and cases. Conclusions These data suggest that the gonadal peptides and gonadotrophins may play a role in the maintenance of bone mass in men. Future confirmatory longitudinal studies are needed.     

Resistin gene variation is associated with systemic inflammation but not plasma adipokine levels, metabolic syndrome or coronary atherosclerosis in nondiabetic Caucasians

Objective Resistin causes insulin resistance and diabetes in mice whereas in humans it is linked to inflammation and atherosclerosis. Few human genetic studies of resistin in inflammation and atherosclerosis have been performed. We hypothesized that the –420C>G putative gain‐of‐function resistin variant would be associated with inflammatory markers and atherosclerosis but not with metabolic syndrome or adipokines in humans. Design and methods We examined the association of three resistin polymorphisms, –852A>G, –420C>G and +157C>T, and related haplotypes with plasma resistin, cytokines, C‐reactive protein (CRP), adipokines, plasma lipoproteins, metabolic syndrome and coronary artery calcification (CAC) in nondiabetic Caucasians (n = 851). Results Resistin levels were higher, dose‐dependently, with the –420G allele (CC 5·9 ± 2·7 ng/ml, GC 6·5 ± 4·0 ng/ml and GG 7·2 ± 4·8 ng/ml, trend P = 0·04) after age and gender adjustment [fold higher for GC + GG vs. CC; 1·07 (1·00–1·15), P < 0·05)]. The –852A>G single nucleotide polymorphism (SNP) was associated with higher soluble tumour necrosis factor‐receptor 2 (sol‐TNFR2) levels in fully adjusted models [1·06 (95% CI 1·01–1·11), P = 0·01)]. The estimated resistin haplotype (GGT) was associated with sol‐TNFR2 (P = 0·04) and the AGT haplotype was related to CRP (P = 0·04) in the fully adjusted models. Resistin SNPs and haplotypes were not associated with body mass index (BMI), fasting glucose, insulin resistance, metabolic syndrome, adipokines or CAC scores. Conclusions Despite modest associations with plasma resistin and inflammatory biomarkers, resistin 5′ variants were not associated with metabolic parameters or coronary calcification. This suggests that resistin is an inflammatory cytokine in humans but has little influence on adiposity, metabolic syndrome or atherosclerosis.     

Acylated ghrelin and leptin in adolescent athletes with amenorrhea, eumenorrheic athletes and controls: a cross-sectional study

Objectives Neuroendocrine factors may predict which athletes develop amenorrhea and which athletes remain eugonadal. Specifically, ghrelin and leptin have been implicated in regulation of GnRH secretion, with ghrelin having inhibitory and leptin, facilitatory effects. We hypothesized that adolescent athletes with amenorrhea (AA) would have higher ghrelin and lower leptin levels than eumenorrheic athletes (EA) and would predict levels of gonadal steroids. Design Cross‐sectional Subjects and measurements We enrolled 58 girls, 21 AA, 19 EA and 18 nonathletic controls 12–18 years old. Fasting blood was drawn for active ghrelin, leptin, E₂ and testosterone. Athletes were > 85% of ideal body weight for age based on body mass index (BMI). Results AA girls had lower BMI than EA and controls (P = 0·003). Log ghrelin was higher in AA than in EA and controls (P < 0·0001), and remained higher after controlling for BMI Z‐scores. Leptin was lower in AA than in the other groups (P < 0·0001), however, the differences did not persist after controlling for BMI Z‐scores. Testosterone was lower in AA than in EA and controls (P = 0·002) and log E₂ trended lower in AA (P = 0·07). We observed inverse associations of log active ghrelin with testosterone (P = 0·01), and positive associations of leptin with testosterone and log E₂ (P = 0·02 and 0·009). Conclusion Higher ghrelin levels, even after controlling for BMI, and lower leptin in AA compared with EA and controls, and their inverse and positive associations, respectively, with gonadal steroids suggest endocrine perturbations that may explain why hypogonadism occurs in some but not all athletes.     

High plasma C-reactive protein (CRP) is related to low paraoxonase-I (PON-I) activity independently of high leptin and low adiponectin in type 2 diabetes mellitus

Objectives In type 2 diabetes mellitus, circulating C‐reactive protein (CRP) is increased, whereas the high density lipoprotein (HDL)‐associated, anti‐oxidative and anti‐inflammatory enzyme, paraoxonase‐I, is decreased. Both high CRP and low paraoxonase‐I activity may predict cardiovascular disease. It is unknown whether lower paraoxonase‐I activity contributes to higher CRP levels in diabetes. In type 2 diabetic and control subjects, we determined the relationship of CRP with paraoxonase‐I when taking account of plasma levels of pro‐ and anti‐inflammatory adipokines. Design and patients In 81 type 2 diabetic patients and 89 control subjects, plasma high‐sensitive CRP, serum paraoxonase‐I activity (arylesterase activity, assayed as the rate of hydrolysis of phenyl acetate into phenol), plasma leptin, adiponectin, resistin and lipids were determined. Results Body mass index (BMI), waist, insulin resistance, triglycerides, CRP, leptin and resistin levels were higher (P < 0·05 to P < 0·001), whereas HDL cholesterol, paraoxonase‐I activity and adiponectin levels were lower (P = 0·02 to P < 0·001) in diabetic compared to control subjects. Multiple linear regression analysis demonstrated that, after controlling for age and gender, CRP was inversely related to paraoxonase‐I activity (β = –0·15, P = 0·028) and adiponectin (β = –0·18, P = 0·009), and positively to leptin (β = 0·33, P < 0·001) and BMI (β = 0·22, P = 0·007), independently of the diabetic state (or of fasting glucose or HbA1c), insulin resistance and lipids (P > 0·20 for all). Conclusions low paraoxonase‐I activity is related to higher CRP, independently of adipokines, as well as of obesity and lipids. Low paraoxonase‐I activity in type 2 diabetes mellitus may contribute to increased cardiovascular risk via an effect on enhanced systemic low‐grade inflammation.