Free triiodothyronine (T3) is negatively associated with fasting ghrelin serum levels in a population sample of euthyroid subjects

PURPOSE

Ghrelin is an orexigenic peptide hormone secreted in times of stress and hunger. It is deeply involved in the regulation of metabolism and energy homeostasis, promoting energy intake and inhibiting energy expenditure on a metabolic level. In this regard, it has in many ways antagonistic effect on the thyroid hormones, which increase metabolism and thus energy expenditure. While there is reasonable evidence of a negative association between ghrelin and hormones of the hypothalamic-pituitary-thyroid (HPT-) axis from studies in patients with thyroid dysfunction and small intervention studies, large-scale studies in healthy subjects are lacking. Therefore, we studied the relationship between total ghrelin serum levels and serum levels of the thyroid hormones in a large sample of euthyroid subjects.

METHODS

Total ghrelin, thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were determined after an overnight fast in 1666 subjects participating in a population-based cross-sectional study ('LIFE') including 10,000 adults. 1012 subjects were included in this analysis. Multiple linear regression analyses were performed.

RESULTS

FT3 was negatively associated with serum ghrelin; total sample: β = - 0.0001, p < 0.001; men: β = - 0.0002, p = 0.013; women: β = - 0.0001, p = 0.010, adjusted for age, BMI, alcohol consumption, serum levels of TSH and fT4 and smoking status. No associations were found between ghrelin serum levels and serum levels of fT4 or TSH.

CONCLUSION

This is to date the largest study investigating the relationship between total serum ghrelin and thyroid hormones. The results point to a complex interaction and should initiate further research.

Children and adolescents with obesity have reduced serum bone turnover markers and 25-hydroxyvitamin D but increased parathyroid hormone concentrations - Results derived from new pediatric reference ranges

BACKGROUND

We aimed to establish age- and gender-specific reference ranges for concentrations of the bone markers osteocalcin (OC), procollagen type 1 N-propeptides (PINP) and carboxy-terminal cross-linking telopeptide of type 1 collagen (CTX-I) as well as for the calciotropic hormones 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH) in healthy infants, children and adolescents. In addition, the effect of age, gender, puberty and body mass index (BMI) on bone markers was investigated.

METHODS

2416 healthy subjects (5714 blood withdrawals), aged 3 months to 17 years, were included to estimate the age- and gender-dependence of reference ranges. Subsequently, measured values of the biomarkers were transformed to standard deviation scores (SDS) and their associations with age, gender and puberty were analyzed. Bone marker-SDS values of the reference cohort were compared with an obese cohort (n = 317 and 489 blood withdrawals) to analyze the effect of BMI.

RESULTS

OC, PINP and CTX-I showed a distinct age- and gender-dependence with peak levels at 10 to 11 years (girls, Tanner 3) and 13 years (boys, Tanner 3-4). Children with obesity had significantly lower SDS levels for OC (-0.44), PINP (-0.27), CTX-I (-0.33), 25(OH)D (-0.43) and higher SDS levels for PTH (+0.44) than the reference cohort.

CONCLUSIONS

OC, PINP and CTX-I vary with age, gender and pubertal stage. The body weight status has to be considered in the interpretation of pediatric OC, PINP, CTX-I, 25(OH)D and PTH levels. Consequences of childhood obesity on bone health should be carefully investigated in long-term studies.

Circulating Pro-Neurotensin in gestational diabetes mellitus

BACKGROUND AND AIMS

Pro-Neurotensin (NT), a stable surrogate parameter of NT, has recently been introduced as a peptide predicting the development of obesity, diabetes mellitus, cardiovascular diseases, and cardiovascular mortality. However, regulation of Pro-NT in gestational diabetes mellitus (GDM) remains uninvestigated.

METHODS AND RESULTS

Pro-NT was quantified in 74 women with GDM, 74 healthy, gestational age-matched, pregnant controls, as well as in a second cohort comprising of 74 healthy, non-pregnant control women, using a chemiluminometric sandwich immunoassay. Pro-NT was correlated to measures of obesity, hypertension, glucose and lipid metabolism, renal function, and inflammation. Mean ± standard deviation of circulating Pro-NT levels were not significantly different in women with GDM (100.2 ± 75.7 pmol/l) as compared to healthy, pregnant controls (103.2 ± 37.4 pmol/l) and healthy, non-pregnant female controls (105.9 ± 38.9 pmol/l) (p = 0.661). Homeostasis model assessment of insulin resistance (HOMA-IR) and creatinine positively correlated with serum Pro-NT in multivariate regression analysis. In contrast, free fatty acids (FFA) were inversely correlated with circulating Pro-NT. Results sustained adjustment for pregnancy status.

CONCLUSIONS

Circulating Pro-NT is not independently associated with GDM, but is with HOMA-IR, creatinine, and FFA even after adjustment for pregnancy status.

Die Rolle der Hypocretine bei affektiven Störungen

Die Polypeptide des lateralen Hypothalamus (LH), Hypocretine (Hcrt), besitzen bedeutsamen Einfluss auf die Schlaf-wach-Rhythmik, prolongierte Aufmerksamkeit und Wachheit, autonome Funktionen und die Energiehomöostase. Das Fehlen von Hcrt führt zur Narkolepsie, aber auch bei affektiven Störungen wird eine diskrete Veränderung des HcrtMetabolismus vermutet. Bei diesen weisen Schlafstörungen, Appetitstörungen sowie veränderte Vigilanzregulation ebenso wie anatomische Verbindungen zwischen dem LH und in der Depression dysregulierter Hypothalamus-Hypophysen-Nebennieren-Achse und dem Locus coeruleus auf einen Einfluss der Hcrt in affektiven Störungen hin. Dieser Übersichtsartikel stellt den derzeitigen Stand der Forschung zu Hcrt bei affektiven Störungen dar und gibt einen Ausblick auf den möglichen Einsatz Hcrt-regulierender Pharmaka in der klinischen Praxis.

The brown-fat-secreted adipokine neuregulin 4 is decreased in gestational diabetes mellitus

AIMS

Neuregulin 4 has recently been recognized as a novel adipokine secreted by brown adipose tissue (BAT), with beneficial effects on murine insulin resistance and hepatic steatosis. Yet, thus far, neither regulation of neuregulin 4 in gestational diabetes mellitus (GDM) nor its longitudinal changes in the peripartum period have been elucidated.

METHODS

Circulating neuregulin 4 levels were measured by ELISA in 74 women with GDM and 74 healthy, gestational-age-matched controls. Also, neuregulin 4 was quantified during pregnancy and compared with postpartum levels in a follow-up study of 25 women with previous GDM and 25 healthy control women.

RESULTS

Women with GDM had lower median serum levels of the novel BAT-secreted adipokine neuregulin 4 (3.0μg/L) compared with healthy (non-GDM) pregnant controls (3.5μg/L; P=0.020), and the area under the glucose curve (AUC_Glucose) was an independent and negative predictor of circulating neuregulin 4 (P=0.033). Also, median postpartum serum concentrations of neuregulin 4 (3.2μg/L) were not significantly different from prepartum levels (2.8μg/L; P=0.328). In addition, neuregulin 4 was positively and independently associated with irisin (P=0.009), but not other BAT-secreted adipokines.

CONCLUSION/INTERPRETATION

Women with GDM have significantly lower circulating neuregulin 4 levels compared with healthy pregnant controls, and the AUC_Glucose is negatively and independently associated with neuregulin 4 during pregnancy. Neuregulin 4 is positively correlated with irisin during pregnancy, as well as in a longitudinal fashion. Future studies are now needed to better elucidate the precise pathomechanisms of the regulation of BAT-secreted adipokines during pregnancy.

HBsAg and anti-HCV screening in elderly hospitalized patients of a German tertiary referral centre

BACKGROUND

Elderly patients are under-represented in hepatitis B and C screening approaches, but may be at increased risk for advanced liver disease. We therefore screened a hospitalized elderly population.

MATERIALS AND METHODS

6011 admissions to the department of internal medicine and neurology within one year were screened for HBsAg and anti-HCV (Elecsys(®)-HBsAg and -anti-HCV). Positive anti-HCV results were confirmed with the INNO-LIA™ assay. HCV-RNA was analyzed by real-time PCR in the case of confirmed positive anti-HCV results, HBV-DNA in the confirmed HBsAg positive individuals.

RESULTS

Patient´s mean age (62.4 years) was 19 years above that of the average German population. The confirmed HBsAg prevalence was 0.6 %. 34 % (n = 12/35) of HBsAg positive cases were newly diagnosed, three of them presented with HBV-DNA levels > 2000 IU/mL. The confirmed anti-HCV prevalence was 0.9 %. 14 % (n = 8/56) of anti-HCV positive patients were previously undiagnosed. HCV-RNA was positive in three of them. In newly diagnosed individuals cirrhosis was present in 1/12 of the HBsAg and in 3/8 of the anti-HCV positive individuals. Compared to non-infected controls, the following risk factors were significantly more frequent in infected patients: (i) HBsAg: sexual exposure (20 % vs. 2 %), blood transfusion before 1992 (13 % vs. 6 %), referrals from nursing homes (10 % vs. 1 %). (ii) Anti-HCV: blood transfusion before 1992 (41 % vs. 6 %), IVDU (25 % vs. 0.5 %), organ transplantation (20 % vs. 5 %), hemodialysis (11 % vs. 3 %).

CONCLUSIONS

HBsAg and anti-HCV were underdiagnosed in a senescent population, however, only few cases presented with advanced liver disease. Referrals from nursing homes were at increased risk for HBV infection.

First Evidence For Glial Pathology In Late Life Minor Depression: s100b Is Increased In Males With Minor Depression

Minor depression is diagnosed when a patient suffers from two to four depressive symptoms for at least two weeks. Though minor depression is a widespread phenomenon, its pathophysiology has hardly been studied. To get a first insight into the pathophysiological mechanisms underlying this disorder we assessed serum levels of biomarkers for plasticity, glial and neuronal function: brain-derived neurotrophic factor (BDNF), S100B and neuron specific enolase (NSE). Twenty-seven subjects with minor depressive episode and 82 healthy subjects over 60 years of age were selected from the database of the Leipzig population-based study of civilization diseases (LIFE). Serum levels of BDNF, S100B and NSE were compared between groups, and correlated with age, body-mass index, and degree of white matter hyperintensities (score on Fazekas scale). S100B was significantly increased in males with minor depression in comparison to healthy males, whereas other biomarkers did not differ between groups (P = 0.10–0.66). NSE correlated with Fazekas score in patients with minor depression (rs = 0.436, P = 0.048) and in the whole sample (rs = 0.252, P = 0.019). S100B correlated with body mass index (rs = 0.246, P = 0.031) and with age in healthy subjects (rs = 0.345, P = 0.002). Increased S100B in males with minor depression, without alterations in BDNF and NSE, supports the glial hypothesis of depression. Correlation between white matter hyperintensities and NSE underscores the vascular hypothesis of late life depression.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Gestational and Non-gestational Trophoblastic Disease. Guideline of the DGGG, OEGGG and SGGG (S2k Level, AWMF Registry No. 032/049, December 2015)

Purpose: The aim was to establish an official interdisciplinary guideline, published and coordinated by the German Society of Gynecology and Obstetrics (DGGG). The guideline was developed for use in German-speaking countries. In addition to the Germany Society of Gynecology and Obstetrics, the guideline has also been approved by the Swiss Society of Gynecology and Obstetrics (SGGG) and the Austrian Society of Gynecology and Obstetrics (OEGGG). The aim was to standardize diagnostic procedures and the management of gestational and non-gestational trophoblastic disease in accordance with the principles of evidence-based medicine, drawing on the current literature and the experience of the colleagues involved in compiling the guideline. Methods: This s2k guideline represents the consensus of a representative panel of experts with a range of different professional backgrounds commissioned by the DGGG. Following a review of the international literature and international guidelines on trophoblastic tumors, a structural consensus was achieved in a formalized, multi-step procedure. This was done using uniform definitions, objective assessments, and standardized management protocols. Recommendations: The recommendations of the guideline cover the epidemiology, classification and staging of trophoblastic tumors; the measurement of human chorionic gonadotropin (hCG) levels in serum, and the diagnosis, management, and follow-up of villous trophoblastic tumors (e.g., partial mole, hydatidiform mole, invasive mole) and non-villous trophoblastic tumors (placental site nodule, exaggerated placental site, placental site tumor, epitheloid trophoblastic tumor, and choriocarcinoma).

Experts' Opinion on the Prenatal Therapy of Congenital Adrenal Hyperplasia (CAH) Due to 21-Hydroxylase Deficiency - Guideline of DGKED in cooperation with DGGG (S1-Level, AWMF Registry No. 174/013, July 2015)

Purpose: This guideline of the German Society of Pediatric Endocrinology and Diabetology (DGKED) is designed to be experts' opinion on the current concept of prenatal therapy for congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH). Several scientific medical societies have also participated in the guideline. It aims to offer guidance to physicians when they counsel affected families about prenatal therapy. Methods: The experts commissioned by the medical societies developed a consensus in an informal process. The consensus was subsequently confirmed by the steering committees of the respective medical societies. Recommendations: Prenatal CAH therapy is an experimental therapy. We recommend designing and using standardized protocols for the prenatal diagnosis, therapy and long-term follow-up of women and children treated prenatally with dexamethasone. If long-term follow-up is not possible, then prenatal therapy should not be performed.

Associations between serum 25-hydroxyvitamin D and bone turnover markers in a population based sample of German children

Severe vitamin D deficiency is known to cause rickets, however epidemiological studies and RCTs did not reveal conclusive associations for other parameters of bone health. In our study, we aimed to investigate the association between serum levels of 25(OH) vitamin D and bone turnover markers in a population-based sample of children. 25(OH)D, calcium (Ca), osteocalcin (OC), and β-Crosslaps (β-CTx) were measured in 2798 ten-year-old children from the German birth cohorts GINIplus and LISAplus. Linear regression was used to determine the association between bone turnover markers and 25(OH)D levels. 25(OH)D, OC, and β-CTx showed a clear seasonal variation. A 10 nmol/l increase in 25(OH)D was significantly associated with a 10.5 ng/l decrease (p < 0.001) in β-CTx after adjustment for design, sex, fasting status, time of blood drawn, BMI, growth rate, and detectable testosterone/estradiol. For OC alone no significant association with 25(OH)D was observed, whereas the β-CTx-to-OC ratio was inversely associated with 25(OH)D (−1.7% change, p < 0.001). When stratifying the analyses by serum calcium levels, associations were stronger in children with Ca levels below the median. This study in school-aged children showed a seasonal variation of 25(OH)D and the bone turnover markers OC and β-CTx. Furthermore a negative association between 25(OH)D and the bone resorption marker β-CTx was observed.

Breast milk leptin and adiponectin in relation to infant body composition up to 2 years

BACKGROUND

Adipokines in breast milk have been associated with infant growth trajectories.

OBJECTIVE

We aimed to explore the relationship of leptin and adiponectin in breast milk with infant weight gain and body composition up to the age of 2 years.

METHODS

Breast milk samples were collected from exclusively or partially breastfeeding mothers at 6 weeks (n = 152) and 4 months (n = 120) post-partum. Leptin and adiponectin were determined in skim breast milk and related to infant growth and fat mass assessed by skin-fold thickness measurements. A total of 118 infants were examined at 2 years.

RESULTS

The levels of both milk adipokines were slightly lower at 4 months compared with 6 weeks post-partum. Breast milk leptin was largely unrelated to infant anthropometric measures up to 2 years. Milk adiponectin tended to be inversely related to early infant anthropometry up to 4 months, but beyond was positively associated with weight gain and the sum of skin-folds up to 2 years.

CONCLUSIONS

Our results suggest that higher adiponectin levels in breast milk might be associated with greater weight gain and higher fat mass in the offspring up to 2 years.

Elevated serum 25(OH)-vitamin D levels are negatively correlated with molar-incisor hypomineralization

To date, the precise etiology of molar-incisor hypomineralization (MIH) is uncertain. Vitamin D plays a key role in hard tissue formation. Therefore, this study aimed to analyze the relationship between serum 25-hydroxy-vitamin D (25(OH)D) status and dental health data obtained from 1,048 children in a 10-year follow-up of the Munich GINIplus and LISAplus birth cohorts. The dental examination included the diagnosis of MIH and recording of (non-)cavitated caries lesions in primary and permanent teeth. Serum 25(OH)D concentrations were taken from blood samples of the 10-year investigation and measured with a fully automated, modular system. Different logistic regression and Poisson hurdle models were calculated. MIH was diagnosed in 13.6% of the study population. Approximately 16.4% of the children demonstrated caries-related defects (D3-4MFS > 0). The mean season-adjusted concentration of 25(OH)D was 75.8 nmol/l (standard deviation 22.0 nmol/l). After adjusting for sex, age, body mass index, parental education, equivalent income, and television/personal computer (TV/PC) viewing hours, a 10 nmol/l increase in serum 25(OH)D concentrations was significantly associated with a lower odds ratio of having MIH (OR = 0.89; P = 0.006). Furthermore, higher 25(OH)D values were associated with a lower number of caries-affected permanent teeth. It is concluded that elevated serum 25(OH)D concentrations were associated with better dental health parameters.

Circulating angiopoietin-like protein 8 is independently associated with fasting plasma glucose and type 2 diabetes mellitus

OBJECTIVE

Angiopoietin-like protein 8 (Angptl8) has recently been introduced as a novel adipokine/hepatokine that promotes pancreatic β-cell proliferation and improves glucose tolerance in mouse models of insulin resistance. However, regulation of Angptl8 in human type 2 diabetes mellitus (T2DM) and renal dysfunction has not been determined.

RESEARCH DESIGN AND METHODS

Serum Angptl8 levels were quantified by ELISA in 62 patients with T2DM as compared with 58 nondiabetic subjects in vivo. Within both groups, about half of the patients were on chronic hemodialysis or had an estimated glomerular filtration rate above 50 mL/min/1.73 m(2). Furthermore, we investigated the effect of insulin and differentiation on Angptl8 mRNA expression in 3T3-L1 adipocytes in vitro.

RESULTS

Median [interquartile range] serum Angptl8 levels were higher in patients with T2DM (1.19 [0.37] μg/L) as compared with nondiabetic subjects (1.03 [0.47] μg/L) (P = .005). Furthermore, the adipokine/hepatokine was significantly higher in women (1.21 [0.47] μg/L) as compared with men (1.05 [0.44] μg/L]) (P = .013). In multivariate analysis, fasting glucose and T2DM but not renal function remained independent and positive predictors of circulating Angptl8 even after adjustment for markers of obesity, lipid status, and inflammation (P < .05). Furthermore, Angptl8 mRNA expression was induced by insulin and during adipogenesis in 3T3-L1 adipocytes in vitro.

CONCLUSIONS

Circulating Angptl8 is positively and independently associated with T2DM and fasting glucose in vivo. Furthermore, Angptl8 mRNA expression is induced by insulin and during adipogenesis in 3T3-L1 adipocytes in vitro.

[Thyroid dysfunction in pregnancy]

Thyroid dysfunction may impair fertility, course of pregnancy and fetal development. Physiological alterations of thyroid function parameters, that occur during pregnancy need to be distinguished from pathophysiological states of hypo- and hyperthyroidism. We performed a literature search (PubMed 1990-2013) and review relevant publications as well as consensus and practice guidelines of international thyroid/endocrine societies. Interpretation of thyroid function values in pregnancy must be based on trimester-specific TSH and T4 ranges. Alterations in thyroid function are present in up to 15% of pregnancies (0.4% overt hypothyroidism, 0.1-0.4% hyperthyroidism) and may lead to preventable complications in the pregnant woman and the fetus. Hypothyroidism is associated with an increased risk for abortion, premature delivery and stillbirth, besides impairment of neurocognitive development. The latter has also been shown in situations of grave iodine deficiency. In addition to new-born screening directed at early recognition of congenital hypothyroidism (incidence 0.03%), universal screening of all pregnant women should be implemented in health care guidelines. Newly diagnosed overt hypothyroidism in a pregnant woman requires immediate levothyroxine substitution at adequate doses. In subclinical hypothyroidism thyroid hormone replacement should be considered. Iodine supplementation is strongly recommended in all pregnant and breast-feeding women. Pregnancy causes a number of, that need to be of thyroid dysfunction. Both hypothyroidism and thyrotoxicosis may impair the course of pregnancy and may negatively affect the fetus. In particular, maternal hypothyroidism may lead to irreparable and detrimental deficits in the neurocognitive development of the fetus. Autoimmune thyroid disease is the most common cause of thyroid dysfunction in pregnancy. Hashimoto's thyroiditis is associated with impaired fertility and miscarriage, and may first manifest in pregnancy due to the increased thyroid hormone requirement. Graves' disease often shows a characteristic course in pregnancy with amelioration of thyrotoxicosis in the second half of pregnancy and exacerbation after delivery. In addition transplacental passage of maternal TSH receptor antibodies may lead to thyrotoxicosis in the fetus and/or newborn.

Clinical evidence-based cutoff limits for GH stimulation tests in children with a backup of results with reference to mass spectrometry

CONTEXT

Cutoff limits of GH stimulation tests to diagnose GH deficiency (GHD) in children and adolescents are not sufficiently validated by clinical studies due to discrepancies in the performance of GH immunoassays and lack of available study populations.

OBJECTIVE

We aimed to establish new cutoff limits for GH stimulation tests based on clinical evidence and compared these immunoassay-based values with an antibody-independent mass spectrometric method.

DESIGN AND SETTING

In a retrospective study, GH cutoff limits for eight different immunoassays and isotope dilution mass spectrometry (ID-MS) were calculated from hGH peak concentrations of short-statured children with and without GHD.

PATIENTS

We compared the serum GH peak concentrations at GH stimulation test of 52 short-statured children and adolescents, who have normal GH secretion at initial workup and normal growth in the follow-up, with the serum GH peak concentrations of 44 GHD patients in the same age range, in order to optimize the cutoff limit calculation.

RESULTS

Discriminant analysis of re-measured GH led to a new cutoff limit of 7.09 μg/l using the iSYS assay (IDS) and the limits for the other seven hGH assays varied between 4.32 and 7.77 μg/l. For ID-MS, cutoffs of 5.48 μg/l (22k GH) and 7.43 μg/l (total GH) were ascertained.

CONCLUSION

The establishment of method-specific clinical evidence-based GH cutoff limits is of importance to ensure adequate clinical diagnosis and treatment of children and adolescents with GHD. ID-MS may become an important tool for providing both reliable and sustainable SI traceability of GH measurements in the future.

Circulating adipocyte fatty acid binding protein is increased in chronic and acute renal dysfunction

BACKGROUND AND AIMS

The adipokine adipocyte fatty acid binding protein (AFABP) is positively associated with the development of the metabolic syndrome, diabetes mellitus, and cardiovascular disease. We hypothesized that AFABP also increases with deteriorating renal function.

METHODS AND RESULTS

Serum AFABP levels were quantified by enzyme linked immunosorbent assay in 532 patients with chronic kidney disease (CKD) covering the whole spectrum of estimated glomerular filtration rate (eGFR) categories from G1 to G5 (study population 1). Furthermore, AFABP was measured in 32 patients before and within 30 h after elective unilateral nephrectomy, a model of acute kidney dysfunction (AKD) (study population 2). Moreover, circulating AFABP was investigated in rats undergoing bilateral nephrectomy (BNE) as compared to sham-operated animals. Median serum AFABP levels adjusted for age, gender, and body mass index significantly increased with increasing eGFR category (G1: 22.0 μg/l; G2: 34.6 μg/l; G3: 56.7 μg/l; G4: 95.2 μg/l; and G5: 173.9 μg/l). Furthermore, renal dysfunction remained positively associated with AFABP in multivariate analysis in this cohort. In patients undergoing unilateral nephrectomy, AFABP increased significantly after surgery (42.1 μg/l) as compared to pre-surgical values (29.3 μg/l). Furthermore, relative changes of post-to-pre-surgical AFABP levels were independently associated with relative changes of post-to-pre-surgical creatinine concentrations. After BNE in rats, AFABP increased significantly as compared to sham-operated animals.

CONCLUSIONS

We show that AFABP is significantly elevated in CKD and AKD patients. Furthermore, measures of renal function are associated with circulating AFABP. Moreover, animal experiments indicate that AFABP levels strongly depend on renal function.

Different associations of adipokines in lean and healthy adults

Regulation of adipokines in lean adults without metabolic disease and without eating disorders has not been comprehensively elucidated. We hypothesized that some of the established associations of these adipocyte-secreted proteins with anthropometric and biochemical measures of glucose homeostasis, lipid metabolism, renal function, as well as inflammation, differ in healthy and low weight adults as compared to overweight/obese patients. Eighty-one subjects with a body mass-index below 22.0 kg/m2 and without malnutrition or eating disorders, as well as fifty overweight/obese patients, were recruited for the study. Serum concentrations of seven adipokines (adiponectin, leptin, adipocyte fatty acid-binding protein [AFABP], chemerin, fibroblast growth factor [FGF]-21, resistin, retinol-binding protein [RBP]-4) were measured by enzyme-linked immunosorbent assays. Lean probands had significantly higher levels of adiponectin and resistin, as well as lower levels of leptin, AFABP, and RBP-4, as compared to overweight/obese subjects. Serum concentrations of adiponectin, leptin, AFABP, chemerin, and resistin were significantly higher in lean women as compared to men (p<0.05). In lean subjects, fasting insulin independently predicted leptin and resistin concentrations. Furthermore, C-reactive protein was independently associated with circulating AFABP and chemerin. Moreover, lean body mass was an independent predictor of leptin, fat mass predicted AFABP levels, whereas RBP-4 was independently correlated to age and triglycerides. In addition, high density lipoprotein cholesterol predicted AFABP. Our results support the notion that several of these adipokines are regulated in a different manner in lean adults as compared to overweight/obese subjects and patients with eating disorders.

Peer problems are associated with elevated serum leptin levels in children

BACKGROUND

Leptin is thought to act as an important mediator in stress reactions. To date, no study has examined the association between psychological stress and leptin levels in children. This study aimed to assess the association between emotional symptoms and peer problems and serum leptin levels in children aged 10 years of the two population-based GINI-plus and LISA-plus birth cohorts.

METHOD

Cross-sectional data from 2827 children aged 10 years were assessed with regard to leptin concentrations in serum and behavioral problems using the parent-reported Strengths and Difficulties Questionnaire (SDQ). Linear regression modeling was applied to determine the likelihood of elevated leptin levels in children with emotional symptoms and peer problems, controlling for socio-economic status (SES), body mass index (BMI), fasting serum leptin levels, pubertal development and sex hormones.

RESULTS

We found that increases in emotional symptoms (exp β adj = 1.03, s.e. = 0.02, p < 0.04) and peer problems (exp β adj = 1.05, s.e. = 0.01, p = 0.0001) were significantly associated with higher serum leptin levels controlled for BMI and sociodemographic factors. Similar results were found when the fasting serum leptin sample was examined (exp β adj = 1.08, s.e. = 0.04, p = 0.0294). Gender-stratified analyses showed a significant relationship between serum leptin and peer problems in girls (exp β adj = 1.05, s.e. = 0.02, p = 0.03), and a borderline significant association in boys (exp β adj = 1.04, s.e. = 0.02, p = 0.05).

CONCLUSIONS

Children with peer problems have higher stress and eat more, acquire a higher body fat mass and thus, through increased leptin resistance, exhibit higher leptin levels.

Maternal insulin resistance, triglycerides and cord blood insulin in relation to post-natal weight trajectories and body composition in the offspring up to 2 years

AIMS

The intrauterine metabolic environment might have a programming effect on offspring body composition. We aimed to explore associations of maternal variables of glucose and lipid metabolism during pregnancy, as well as cord blood insulin, with infant growth and body composition up to 2 years post-partum.

METHODS

Data of pregnant women and their infants came from a randomized controlled trial designed to investigate the impact of nutritional fatty acids on adipose tissue development in the offspring. Of the 208 pregnant women enrolled, 118 infants were examined at 2 years. In the present analysis, maternal fasting plasma insulin, homeostasis model assessment of insulin resistance and serum triglycerides measured during pregnancy, as well as insulin in umbilical cord plasma, were related to infant growth and body composition assessed by skinfold thickness measurements and abdominal ultrasonography up to 2 years of age.

RESULTS

Maternal homeostasis model assessment of insulin resistance at the 32nd week of gestation was significantly inversely associated with infant lean body mass at birth, whereas the change in serum triglycerides during pregnancy was positively associated with ponderal index at 4 months, but not at later time points. Cord plasma insulin correlated positively with birthweight and neonatal fat mass and was inversely associated with body weight gain up to 2 years after multiple adjustments. Subsequent stratification by gender revealed that this relationship with weight gain was stronger, and significant only in girls.

CONCLUSIONS

Cord blood insulin is inversely associated with subsequent infant weight gain up to 2 years and this seems to be more pronounced in girls.

Is a child's growth pattern early in life related to serum adipokines at the age of 10 years?

BACKGROUND/OBJECTIVES

Growth parameters during infancy and early childhood might predict adipokine levels later in life. This study investigates the association between peak growth velocities, body mass index (BMI) and age at adiposity rebound (AR), with leptin and adiponectin levels at age 10 years.

SUBJECTS/METHODS

Peak height (PHV) and weight (PWV) velocities were calculated from height and weight measurements obtained between birth and age 2 years from 2880 children participating in the GINIplus (German Infant Nutritional Intervention plus environmental and genetic influences on allergy development) and LISAplus (Influences of Lifestyle-Related Factors on the Immune System and the Development of Allergies in Childhood plus Air Pollution and Genetics) birth cohorts. BMI and age at AR were calculated using BMI measurements between age 1.5 and 12 years. Blood samples were collected during a physical examination at age 10. Adiponectin and leptin levels were measured by radioimmunoassay. Linear regression models were fitted after adjustment for potential confounding factors and results are presented per interquartile range increase in the exposure.

RESULTS

Age at AR was negatively associated with leptin in males and females (percent difference β*: -41.71%; 95% confidence interval: (-44.34;-38.96) and β*: -43.22%; (-45.59; -40.75), respectively). For both males and females PWV (β*: 14.23%; (7.60; 21.26) and β*: 18.54%; (10.76; 26.87), respectively) and BMI at AR (β*: 63.08%; (55.04; 71.53) and β*: 67.02%; (59.30; 75.10), respectively) were positively associated with leptin levels. PHV showed a positive effect on leptin in females only (β*: 10.75%; (3.73; 18.25)). Growth parameters were not significantly associated with adiponectin except for age at AR among females (β: 0.75 ng/ml; (0.42; 1.09)) and PWV among males (β: 0.45 ng/ml; (0.11; 0.79)).

CONCLUSION

Growth patterns in early life may be associated with leptin levels at age 10 years.

Long-term exposure to traffic-related air pollution and insulin resistance in children: results from the GINIplus and LISAplus birth cohorts

AIMS/HYPOTHESIS

Epidemiological studies that have examined associations between long-term exposure to traffic-related air pollution and type 2 diabetes mellitus in adults are inconsistent, and studies on insulin resistance are scarce. We aimed to assess the association between traffic-related air pollution and insulin resistance in children.

METHODS

Fasting blood samples were collected from 397 10-year-old children in two prospective German birth cohort studies. Individual-level exposures to traffic-related air pollutants at the birth address were estimated by land use regression models. The association between air pollution and HOMA of insulin resistance (HOMA-IR) was analysed using a linear model adjusted for several covariates including birthweight, pubertal status and BMI. Models were also further adjusted for second-hand smoke exposure at home. Sensitivity analyses that assessed the impact of relocating, study design and sex were performed.

RESULTS

In all crude and adjusted models, levels of insulin resistance were greater in children with higher exposure to air pollution. Insulin resistance increased by 17.0% (95% CI 5.0, 30.3) and 18.7% (95% CI 2.9, 36.9) for every 2SDs increase in ambient NO2 and particulate matter ≤10 μm in diameter, respectively. Proximity to the nearest major road increased insulin resistance by 7.2% (95% CI 0.8, 14.0) per 500 m.

CONCLUSIONS/INTERPRETATION

Traffic-related air pollution may increase the risk of insulin resistance. Given the ubiquitous nature of air pollution and the high incidence of insulin resistance in the general population, the associations examined here may have potentially important public health effects despite the small/moderate effect sizes observed.

Sex steroid hormones are not altered in great saphenous veins after varicose vein treatment in male patients

OBJECTIVE

The objective of this study was to assess differences in blood samples (sex steroid hormone levels and blood counts) before and after surgical treatment of incompetent great saphenous veins (GSV) in males.

METHODS

Antecubital vein and GSV blood samples were taken from 11 men with varicose veins and GSV reflux before and after treatment. Six patients were treated with high ligation, stripping and phlebectomy. Five patients were treated with endoluminal radiofrequency ablation and phlebectomy. After a four-year follow-up period (FU) cubital vein and GSV blood samples were taken again.

RESULTS

In men with varicose veins, significantly higher (P < 0.05) serum testosterone (median 25.18 nmol/L, range 8.82-225.1) and oestradiol (median 179 pmol/L, range 79-941) levels were found in the saphenous vein samples before and after the FU (testosterone 18.8 nmol/L, range 7.96-83.1, oestradiol 171 pmol/L range 125-304) compared with the cubital vein samples before therapy (testosterone 15.72 nmol/L, range 8.36-23.29; oestradiol 84 pmol/L, range 41-147) and after the FU (testosterone 14.5 nmol/L, range 6.10-22.2, oestradiol 117 pmol/L, range 95-165). After the FU, one patient demonstrated recurrent varicose veins with groin neovascularization. Another presented with axial reflux of the anterior accessory saphenous vein. Further differences in blood counts and serum androstenedione levels between the upper and lower extremities were not detected.

CONCLUSION

The differences between testosterone and oestradiol levels in the leg veins compared with the cubital veins persist after treating men with refluxing saphenous veins. These results suggest that local hormone regulation may be different between leg and arm veins in men with varicose veins.

Age-dependent inhibin B concentration in relation to FSH and semen sample qualities: a study in 2448 men

Inhibin B is an important serum marker of spermatogenesis, whereas sensitivity and predicting power for the spermatogenic situation at several ages are under debate. We performed a retrospective analysis of data from 2448 men who attended our University-based male infertility clinic to evaluate inhibin B in relation to age and semen sample qualities in comparison with FSH. Moreover, the range of inhibin B in 82 nonobstructive azoospermic patients was correlated with the sperm retrieval in testicular sperm extraction procedures. Inhibin B correlated with FSH (Spearman rank correlation (R)=−0.50; P<0.00001). Inhibin B and inhibin B/FSH ratio (IFR) showed an inverse U-shaped dependence on age, whereas FSH showed a U-shaped dependence on age (optimum 20–40 years). However, in men with normal spermiograms inhibin B concentrations did not differ between age groups. Their levels of inhibin B amounted to 130.5, 54.5–247 ng/l (median, 10th–90th precentile), and of IFR to 38.3, 12.5–104.8 (median, 10th–90th percentile), which might be taken as the reference range. Using the 10th percentile of IFR, correct classification in normal or pathological semen groups was achieved in 99.1%. The percentage of aniline blue-negative spermatozoa, i.e. mature spermatozoa with protamines, did not correlate with FSH (P>0.05) but with inhibin B (R=0.15, P<0.001). The probability of retrieving testicular spermatozoa decreased with declining inhibin B: <20 ng/l sperm could never be found. Our results from a large group of men with a wide spectrum of semen qualities allow estimating reference values for inhibin B and IFR. Inhibin B and especially the IFR are more sensitive markers of male infertility than FSH alone.

Overweight and obesity are associated with neuronal injury in the human cerebellum and hippocampus in young adults: a combined MRI, serum marker and gene expression study

There is growing evidence that obesity represents a risk for enhanced gray matter (GM) density changes comparable to those demonstrated for mild cognitive impairment in the elderly. However, it is not clear what mechanisms underlie this apparent alteration in brain structure of overweight subjects and to what extent these changes can already occur in the adolescent human brain. In the present volumetric magnetic resonance imaging study, we investigated GM changes and serum levels of neuron-specific enolase (NSE), a marker for neuronal injury, in a set of overweight/obese subjects and controls. We report a negative correlation for overweight and obese subjects between serum NSE and GM density in hippocampal and cerebellar regions. To validate our neuroimaging findings, we complement these data with NSE gene expression information obtained from the Allen Brain atlas. GM density changes were localized in brain areas that mediate cognitive function-the hippocampus associated with memory performance, and the cognitive cerebellum (lateral posterior lobes) associated with executive, spatial and linguistic processing. The data of our present study highlight the importance of extending current research on cognitive function and brain plasticity in the elderly in the context of obesity to young adult subjects and include serum biomarkers to validate imaging findings generally.

Serum levels of the adipokine zinc-α2-glycoprotein are increased in preeclampsia

BACKGROUND

Preeclampsia (PE) is associated with facets of the metabolic syndrome and an increased future metabolic and cardiovascular risk for mother and newborn. Recently, zinc-α2-glycoprotein (ZAG) has been proposed as a new adipokine involved in the pathogenesis of obesity.

AIM

In the current study, we investigated ZAG serum levels in PE patients as compared to healthy gestational age-matched controls.

SUBJECTS AND METHODS

We quantified serum concentrations of ZAG in patients with PE (no.=37) as compared to healthy gestational age-matched controls (no.=37) by enzyme-linked immunosorbent assay. Furthermore, association of this adipokine with renal function, glucose and lipid metabolism, as well as inflammation was studied.

RESULTS

Median serum ZAG levels were 1.4-fold higher in PE patients (58.8 mg/l) as compared to controls (41.9 mg/l) (p<0.01). Furthermore, circulating ZAG was positively correlated to systolic and diastolic blood pressure, creatinine, triglycerides, and leptin in univariate analyses. In multiple regression analysis, creatinine remained independently associated with ZAG.

CONCLUSIONS

We demonstrate that maternal ZAG serum concentrations are significantly increased in PE. Furthermore, renal function is an independent predictor of circulating ZAG.

Differences in zinc status and the leptin axis in anorexic and recovered adolescents and young adults: a pilot study

BACKGROUND

Evidence from animal studies suggests that leptin metabolism is associated with zinc (Zn) status. However, research investigating this relationship in adolescents and young adults with anorexia nervosa (AN) is scarce; the present study aims to fill that gap.

METHODS

Serum concentrations of leptin, the soluble leptin receptor (sOB-R) and the free leptin index (FLI) were obtained in healthy control subjects (n=19), acutely ill individuals (n=14) and recovered patients with AN (n=15). Serum Zn concentrations noted in previous research data were also incorporated for all groups.

RESULTS

Leptin, FLI and Zn concentrations were higher in recovered subjects with AN when compared with acutely ill AN patients. Remitted patients showed higher sOB-R concentrations but no difference in FLI compared with the control group. Leptin and FLI were lower in the acutely ill patients compared with the control subjects, who showed no differences in Zn concentrations. Zn concentrations were not correlated with leptin, sOB-R or FLI concentrations in any of the three investigated subgroups.

CONCLUSIONS

The present investigation does not entirely support an association between Zn, Leptin and FLI concentrations in subjects with AN, possibly due to limited statistical power. Further research and replication of the present findings related to the interaction between leptin and Zn is warranted. However, with respect to serum leptin levels the data of the present investigation indicate that acutely ill and remitted patients with AN differ as regards serum leptin concentrations and FLI, which is in line with previous research.