Reference values for serum total adiponectin in healthy non-obese children and adolescents

Lipid profiling identifies modifiable signatures of cardiometabolic risk in children and adolescents with obesity

Pediatric obesity is a progressive, chronic disease that can lead to serious cardiometabolic complications. Here we investigated the peripheral lipidome in 958 children and adolescents with overweight or obesity and 373 with normal weight, in a cross-sectional study. We also implemented a family-based, personalized program to assess the effects of obesity management on 186 children and adolescents in a clinical setting. Using mass spectrometry-based lipidomics, we report an increase in ceramides, alongside a decrease in lysophospholipids and omega-3 fatty acids with obesity metabolism. Ceramides, phosphatidylethanolamines and phosphatidylinositols were associated with insulin resistance and cardiometabolic risk, whereas sphingomyelins showed inverse associations. Additionally, a panel of three lipids predicted hepatic steatosis as effectively as liver enzymes. Lipids partially mediated the association between obesity and cardiometabolic traits. The nonpharmacological management reduced levels of ceramides, phospholipids and triglycerides, indicating that lowering the degree of obesity could partially restore a healthy lipid profile in children and adolescents.

Altered Glucagon and GLP-1 Responses to Oral Glucose in Children and Adolescents With Obesity and Insulin Resistance

CONTEXT

Pediatric obesity is characterized by insulin resistance, yet it remains unclear whether insulin resistance contributes to abnormalities in glucagon and incretin secretion.

OBJECTIVE

To examine whether fasting and stimulated glucagon, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic polypeptide (GIP) concentrations differ between children and adolescents with obesity and insulin resistance (OIR), obesity and normal insulin sensitivity (OIS), and controls with normal weight (NW).

METHODS

80 (34 boys) children and adolescents, aged 7-17 years with OIR (n = 22), OIS (n = 22), and NW (n = 36) underwent an oral glucose tolerance test with measurements of serum insulin, plasma glucose, glucagon, total GLP-1, and total GIP. Homeostatic model assessment of insulin resistance (HOMA-IR), single point insulin sensitivity estimator (SPISE), Matsuda index, insulinogenic index (IGI), and oral disposition index (ODI) were calculated.

RESULTS

Fasting concentrations of glucagon and GLP-1 were higher in the OIR group, with no significant differences for GIP. The OIR group had higher glucagon total area under the curve (tAUC0-120) and lower GLP-1 incremental AUC (iAUC0-120), with no significant differences in GIP iAUC0-120. Higher fasting glucagon was associated with higher HOMA-IR, lower Matsuda index, lower SPISE, higher IGI, and higher plasma alanine transaminase, whereas higher fasting GLP-1 was associated with higher HOMA-IR, lower Matsuda index, and lower ODI. Higher glucagon tAUC0-120 was associated lower SPISE and lower Matsuda index, whereas lower GLP-1 iAUC0-120 was associated with a higher HOMA-IR, lower Matsuda index, and lower ODI.

CONCLUSION

Children and adolescents with OIR have elevated fasting concentrations of glucagon and GLP-1, higher glucagon and lower GLP-1 responses during an OGTT compared to those with OIS and NW. In contrast, individuals with OIS have similar hormone responses to those with NW.

Pediatric Features of Genetic Predisposition to Polycystic Ovary Syndrome

CONTEXT

Polycystic ovary syndrome (PCOS) has historically been conceptualized as a disorder of the reproductive system in women. However, offspring of women with PCOS begin to show metabolic features of PCOS in childhood, suggestive of childhood manifestations.

OBJECTIVE

To identify childhood manifestations of genetic risk for PCOS.

METHODS

We calculated a PCOS polygenic risk score (PRS) for 12 350 girls and boys in 4 pediatric cohorts-ALSPAC (UK), COPSAC (Denmark), Project Viva (USA), and The HOLBÆK Study (Denmark). We tested for association of the PRS with PCOS-related phenotypes throughout childhood and with age at pubarche and age at peak height velocity and meta-analyzed effects across cohorts using fixed-effect models.

RESULTS

Higher PRS for PCOS was associated with higher body mass index in midchildhood (0.05 kg/m2 increase per 1 SD of PRS, 95% CI 0.03, 0.07, P = 3 × 10-5) and higher risk of obesity in early childhood (OR 1.34, 95% CI 1.13, 1.59, P = .0009); both persisted through late adolescence (P all ≤.03). Higher PCOS PRS was associated with earlier age at pubarche (0.85-month decrease per 1 SD of PRS, 95% CI -1.44, -0.26, P = .005) and younger age at peak height velocity (0.64-month decrease per 1 SD of PRS, 95% CI -0.94, -0.33, P = 4 × 10-5).

CONCLUSION

Genetic risk factors for PCOS are associated with alterations in metabolic, growth, and developmental traits in childhood. Thus, PCOS may not simply be a condition that affects women of reproductive age but, rather, a possible manifestation of an underlying condition that affects both sexes starting in early life.

An adult-based genetic risk score for liver fat associates with liver and plasma lipid traits in children and adolescents

BACKGROUND & AIMS

Genome-wide association studies have identified steatogenic variants that also showed pleiotropic effects on cardiometabolic traits in adults. We investigated the effect of eight previously reported genome-wide significant steatogenic variants, individually and combined in a weighted genetic risk score (GRS), on liver and cardiometabolic traits, and the predictive ability of the GRS for hepatic steatosis in children and adolescents.

APPROACH & RESULTS

Children and adolescents with overweight (including obesity) from an obesity clinic group (n = 1768) and a population-based group (n = 1890) were included. Cardiometabolic risk outcomes and genotypes were obtained. Liver fat was quantified using 1 H-MRS in a subset of 727 participants. Variants in PNPLA3, TM6SF2, GPAM and TRIB1 were associated with higher liver fat (p < .05) and with distinct patterns of plasma lipids. The GRS was associated with higher liver fat content, plasma concentrations of alanine transaminase (ALT), aspartate aminotransferase (AST) and favourable plasma lipid levels. The GRS was associated with higher prevalence of hepatic steatosis (defined as liver fat ≥5.0%) (odds ratio per 1-SD unit: 2.17, p = 9.7E-10). A prediction model for hepatic steatosis including GRS alone yielded an area under the curve (AUC) of 0.78 (95% CI 0.76-0.81). Combining the GRS with clinical measures (waist-to-height ratio [WHtR] SDS, ALT, and HOMA-IR) increased the AUC up to 0.86 (95% CI 0.84-0.88).

CONCLUSIONS

The genetic predisposition for liver fat accumulation conferred risk of hepatic steatosis in children and adolescents. The liver fat GRS has potential clinical utility for risk stratification.

High Plasma Levels of Soluble Lectin-like Oxidized Low-Density Lipoprotein Receptor-1 Are Associated With Inflammation and Cardiometabolic Risk Profiles in Pediatric Overweight and Obesity

Background Lectin-like oxidized low-density lipoprotein (ox-LDL) receptor-1 is a scavenger receptor for oxidized low-density lipoprotein. In adults, higher soluble lectin-like ox-LDL receptor-1 (sLOX-1) levels are associated with cardiovascular disease, type 2 diabetes, and obesity, but a similar link in pediatric overweight/obesity remains uncertain. Methods and Results Analyses were based on the cross-sectional HOLBAEK Study, including 4- to 19-year-olds from an obesity clinic group with body mass index >90th percentile (n=1815) and from a population-based group (n=2039). Fasting plasma levels of sLOX-1 and inflammatory markers were quantified, cardiometabolic risk profiles were assessed, and linear and logistic regression analyses were performed. Pubertal/postpubertal children and adolescents from the obesity clinic group exhibited higher sLOX-1 levels compared with the population (P<0.001). sLOX-1 positively associated with proinflammatory cytokines, matrix metalloproteinases, body mass index SD score, waist SD score, body fat %, plasma alanine aminotransferase, serum high-sensitivity C-reactive protein, plasma low-density lipoprotein cholesterol, triglycerides, systolic and diastolic blood pressure SD score, and inversely associated with plasma high-density lipoprotein cholesterol (all P<0.05). sLOX-1 positively associated with high alanine aminotransferase (odds ratio [OR], 1.16, P=4.1 E-04), insulin resistance (OR, 1.16, P=8.6 E-04), dyslipidemia (OR, 1.25, P=1.8 E-07), and hypertension (OR, 1.12, P=0.02). Conclusions sLOX-1 levels were elevated during and after puberty in children and adolescents with overweight/obesity compared with population-based peers and associated with inflammatory markers and worsened cardiometabolic risk profiles. sLOX-1 may serve as an early marker of cardiometabolic risk and inflammation in pediatric overweight/obesity. Registration The HOLBAEK Study, formerly known as The Danish Childhood Obesity Biobank, ClinicalTrials.gov identifier number NCT00928473, https://clinicaltrials.gov/ct2/show/NCT00928473 (registered June 2009).

Biomarkers Predictive of Metabolic Syndrome and Cardiovascular Disease in Childhood Cancer Survivors

The improvement in childhood cancer treatments resulted in a marked improvement in the survival of pediatric cancer patients. However, as survival increased, it was also possible to observe the long-term side effects of cancer therapies. Among these, metabolic syndrome is one of the most frequent long-term side effects, and causes high mortality and morbidity. Consequently, it is necessary to identify strategies that allow for early diagnosis. In this review, the pathogenetic mechanisms of metabolic syndrome and the potential new biomarkers that can facilitate its diagnosis in survivors of pediatric tumors are analyzed.

Hyperglucagonemia in Pediatric Adiposity Associates With Cardiometabolic Risk Factors but Not Hyperglycemia

CONTEXT

In adults, hyperglucagonemia is associated with type 2 diabetes, impaired glucose tolerance, and obesity. The role of glucagon in pediatric overweight/obesity remains unclear.

OBJECTIVE

We examined whether fasting concentrations of glucagon are elevated in youth with overweight/obesity and whether this associates with cardiometabolic risk profiles.

METHODS

Analyses were based on the cross-sectional HOLBAEK study, including children and adolescents 6 to 19 years of age, with overweight/obesity from an obesity clinic group (n = 2154) and with normal weight from a population-based group (n = 1858). Fasting concentrations of plasma glucagon and cardiometabolic risk outcomes were assessed, and multiple linear and logistic regressions models were performed.

RESULTS

The obesity clinic group had higher glucagon concentrations than the population-based group (P < 0.001). Glucagon positively associated with body mass index (BMI) standard deviation score (SDS), waist, body fat %, liver fat %, alanine transaminase (ALT), high-sensitivity C-reactive protein, homeostasis model assessment of insulin resistance, insulin, C-peptide, LDL-C, triglycerides, SDS of diastolic and systolic blood pressure, and was inversely associated with fasting glucose. The inverse relationship between glucagon and glucose was attenuated in individuals with high BMI SDS and high fasting insulin. Glucagon was associated with a higher prevalence of insulin resistance, increased ALT, dyslipidemia, and hypertension, but not with hyperglycemia. Glucagon was positively associated with fasting total glucagon-like peptide-1.

CONCLUSION

Compared with normal weight peers, children and adolescents with overweight/obesity had elevated concentrations of fasting glucagon, which corresponded to worsened cardiometabolic risk outcomes, except for hyperglycemia. This suggests hyperglucagonemia in youth may precede impairments in glucose regulation.

Glucagon-Like Peptide-1 Is Associated With Systemic Inflammation in Pediatric Patients Treated With Hematopoietic Stem Cell Transplantation

Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are challenged with severe side effects, which are propagated by mucosal barrier disruption, and the related microbial translocation and systemic inflammation. Glucagon-like peptide-1 (GLP-1), a well-known incretin hormone, possesses anti-inflammatory properties and promotes regeneration of damaged intestinal epithelium in animal studies. We hypothesized that the immense inter-individual variation in the degree of mucosal damage and systemic inflammation, seen after HSCT is influenced by endogenous GLP-1 and could be related to acute post-transplant complications. In this prospective study we measured serial weekly fasting plasma GLP-1, along with C-reactive protein (CRP), and citrulline in 82 pediatric patients during allogeneic HSCT together with a fasting plasma GLP-1 in sex- and age-matched healthy controls. Overall, GLP-1 levels were increased in the patients during the course of HSCT compared with the controls, but tended to decrease post-transplant, most pronounced in patients receiving high-intensity conditioning regimen. The increase in CRP seen in the early post-transplant phase was significantly lower from day +8 to +13 in patients with GLP-1 above the upper quartile (>10 pmol/L) at day 0 (all P ≤ 0.03). Similar findings were seen for peak CRP levels after adjusting for type of conditioning (-47.0%; 95% CI, -8.1 - -69.4%, P = 0.02). Citrulline declined significantly following the transplantation illustrating a decrease in viable enterocytes, most evident in patients receiving high-intensity conditioning regimen. GLP-1 levels at day 0 associated with the recovery rate of citrulline from day 0 to +21 (34 percentage points (pp)/GLP-1 doubling; 95% CI, 10 - 58pp; P = 0. 008) and day 0 to day +90 (48 pp/GLP-1 doubling; 95% CI, 17 - 79pp; P = 0. 004), also after adjustment for type of conditioning. This translated into a reduced risk of acute graft-versus-host disease (aGvHD) in patients with highest day 0 GLP-1 levels (>10 pmol/L) (cause-specific HR: 0.3; 95% CI, 0.2 - 0.9, P = 0.02). In conclusion, this study strongly suggests that GLP-1 influences regeneration of injured epithelial barriers and ameliorates inflammatory responses in the early post-transplant phase.

Children with metabolically healthy obesity have a worse metabolic profile compared to normal-weight peers: a cross-sectional study

PURPOSE

A phenotype of metabolically healthy obesity (MHO) has been described in youth with obesity, but data are still scarce in this age group. The aim of the current study was to describe and compare clinical and laboratory parameters related to obesity among three different groups of youth, namely youth with normal weight (NW), with MHO, and with metabolically unhealthy obesity (MUO).

METHODS

One hundred and three youngsters with obesity were divided according to 2018 consensus-based criteria into those with MHO [n = 49, age (±SD): 10.9 ± 2.9 years] and those with MUO [n = 54, 11.5 ± 2.7 years] and were compared to age-, sex- and Tanner-matched NW [n = 69, 11.3 ± 2.9 years]. Several obesity-related parameters were investigated for all three groups of children. Comparisons were made by analysis of variance (ANOVA) followed by the Fisher's PLSD test.

RESULTS

Youth with MHO had lower systolic (p < 0.001) and diastolic (p < 0.01) blood pressure z-score and triglycerides (p < 0.01), but higher HDL-C (p < 0.001), total cholesterol (p < 0.05), and apo-A1 (p < 0.05) compared to those with MUO. Compared to controls, both children with MHO and MUO showed higher fasting insulin (p < 0.05), HOMA-IR (p < 0.05), and QUICKI (p < 0.001). Similarly, both groups had higher hsCRP, fibrinogen, uric acid, and leptin compared to controls (for all, p < 0.001), while their adiponectin was lower (p < 0.05). Visfatin was higher in children with MUO compared to controls (p < 0.01), and it showed a trend to be lower in children with MHO compared to those with MUO (p = 0.1).

CONCLUSION

This study provides evidence that children identified as having MHO by the consensus-based criteria had better metabolic profiles than youth with MUO, but worse than NW. Further research is needed in pediatric populations both regarding MHO criteria and the nature of the MHO phenotype per se.

Adiponectin and Asthma: Knowns, Unknowns and Controversies

Adiponectin is an adipokine associated with the healthy obese phenotype. Adiponectin increases insulin sensitivity and has cardio and vascular protection actions. Studies related to adiponectin, a modulator of the innate and acquired immunity response, have suggested a role of this molecule in asthma. Studies based on various asthma animal models and on the key cells involved in the allergic response have provided important insights about this relation. Some of them indicated protection and others reversed the balance towards negative effects. Many of them described the cellular pathways activated by adiponectin, which are potentially beneficial for asthma prevention or for reduction in the risk of exacerbations. However, conclusive proofs about their efficiency still need to be provided. In this article, we will, briefly, present the general actions of adiponectin and the epidemiological studies supporting the relation with asthma. The main focus of the current review is on the mechanisms of adiponectin and the impact on the pathobiology of asthma. From this perspective, we will provide arguments for and against the positive influence of this molecule in asthma, also indicating the controversies and sketching out the potential directions of research to complete the picture.

Fasting Plasma GLP-1 Is Associated With Overweight/Obesity and Cardiometabolic Risk Factors in Children and Adolescents

CONTEXT

The importance of fasting glucagon-like peptide-1 (GLP-1) in altered metabolic outcomes has been questioned.

OBJECTIVE

This work aimed to assess whether fasting GLP-1 differs in children and adolescents with overweight/obesity compared to a population-based reference, and whether concentrations predict cardiometabolic risk (CMR) factors.

METHODS

Analyses were based on The Danish Childhood Obesity Data- and Biobank, a cross-sectional study including children and adolescents, aged 6 to 19 years, from an obesity clinic group (n = 1978) and from a population-based group (n = 2334). Fasting concentrations of plasma total GLP-1 and quantitative CMR factors were assessed. The effects of GLP-1 as a predictor of CMR risk outcomes were examined by multiple linear and logistic regression modeling.

RESULTS

The obesity clinic group had higher fasting GLP-1 concentrations (median 3.3 pmol/L; interquartile range, 2.3-4.3 pmol/L) than the population-based group (2.8 pmol/L; interquartile range, 2.1-3.8 pmol/L; P < 2.2E-16). Body mass index SD score (SDS), waist circumference, and total body fat percentage were significant predictors of fasting GLP-1 concentrations in boys and girls. Fasting GLP-1 concentrations were positively associated with homeostasis model assessment of insulin resistance, fasting values of insulin, high-sensitivity C-reactive protein, C-peptide, triglycerides, alanine transaminase (ALT), glycated hemoglobin A1c, and SDS of diastolic and systolic blood pressure. A 1-SD increase in fasting GLP-1 was associated with an increased risk of insulin resistance (odds ratio [OR] 1.59), dyslipidemia (OR 1.16), increased ALT (OR 1.14), hyperglycemia (OR 1.12) and hypertension (OR 1.12).

CONCLUSION

Overweight/obesity in children and adolescents is associated with increased fasting plasma total GLP-1 concentrations, which was predictive of higher CMR factors.

Adiponectin, HOMA-Adiponectin, HOMA-IR in Children and Adolescents: Ouro Preto Study

OBJECTIVES

To examine the association and predictive capacity of adiponectin levels, HOMA-AD and HOMA-IR indexes with metabolic risk markers in children and adolescents.

METHODS

A cross-sectional study was conducted with 691 children and adolescents (7-14 y), of both sexes. Demographic (sex, age), anthropometric (weight, height, body mass index, waist circumference, body fat), biochemical [total cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), triglycerides, fasting glycemia, insulin and adiponectin] and clinical parameters (arterial blood pressure) were analyzed.

RESULTS

In multiple linear regression models, metabolic risk were analyzed in relation to adiponectin levels, HOMA-AD and HOMA-IR. ROC curve analysis was used to define the cut-off for metabolic syndrome for each method studied. Adiponectin level was inversely correlated with weight (r = -0.12; p = 0.01), waist circumference (WC) (r = -0.12; p = 0.01), and triglycerides (r = -0.11; p = 0.02); it was directly correlated with HDL (r = 0.10; p = 0.03) only in the adolescents. In the final linear regression model, after adjustment, only triglycerides (p = 0.03) and HDL (p = 0.04) remained significant. However, HOMA-AD and HOMA-IR were associated with metabolic risk and were the most suitable methods for metabolic syndrome screening in both age groups. For children, independent variables explained 16.0% and 14.5% of HOMA-AD and HOMA-IR, respectively. For adolescents, R² was higher in HOMA-AD and HOMA-IR models (R²_adjusted = 31.9% and R²_adjusted = 29.6%, respectively).

CONCLUSIONS

HOMA-AD and HOMA-IR are better explained by metabolic markers than adiponectin levels.

Low-grade inflammation independently associates with cardiometabolic risk in children with overweight/obesity

BACKGROUND AND AIMS

Pediatric obesity associates with both low-grade inflammation and cardiometabolic risk on the population level. Yet on an individual patient level, overweight/obesity does not always equal increased cardiometabolic risk. In this study, we examine whether low-grade inflammation associates with cardiometabolic risk in Danish children, independent of degree of adiposity. We further assess the value of integrating multiple inflammation markers to identify children with very-high cardiometabolic risk profiles.

METHOD AND RESULTS

We studied 2192 children and adolescents aged 6-18 years from an obesity clinic cohort and a population-based cohort, in a cross-sectional study design. Anthropometry, blood pressure, pubertal stage and body composition by dual-energy X-ray absorptiometry were assessed, and biomarkers including fasting serum high sensitivity C-reactive protein (hsCRP), white blood cells (WBC), resistin, lipid profile and glucose metabolism were measured. Adjusted correlation analysis and odds ratios were calculated. We found that, independent of degree of adiposity, having high-normal inflammation marker concentrations associated with increased cardiometabolic risk: for girls, hsCRP >0.57-9.98 mg/L (mid/upper tertile) associated with ~2-fold higher odds of dyslipidemia and hepatic steatosis (vs. lower tertile). For both sexes, WBC >7.0-12.4 10⁹/L (upper tertile) associated with 2.5-fold higher odds of insulin resistance. Lastly, children with multiple inflammation markers in the high-normal range exhibited the most severe cardiometabolic risk profile.

CONCLUSION

Low-grade inflammation associates with cardiometabolic risk in children independent of degree of adiposity. The associations vary with sex and inflammation marker measured. Finally, integrating multiple low-grade inflammation markers identifies a very-high-risk subgroup of children with overweight/obesity and may have clinical value.

Leptin, adiponectin, and their ratio as markers of insulin resistance and cardiometabolic risk in childhood obesity

BACKGROUND

It is imperative to develop markers for risk stratification and detection of cardiometabolic comorbidities in children with obesity. The adipokines leptin and adiponectin are both involved in fat mass regulation and the development of obesity-related disorders; furthermore, their ratio (leptin/adiponectin ratio) is suggested to be associated with insulin resistance and cardiometabolic risk.

OBJECTIVE

To evaluate associations between fasting serum concentrations of the adipokines (total leptin and adiponectin as well as the L/A ratio) and cardiometabolic comorbidities in children with overweight/obesity.

METHODS

A total of 2258 children with overweight/obesity or normal weight aged 6 to 18 years were studied. Differences in anthropometrics and adipokine concentrations were tested using Wilcoxon rank-sum test. Associations between the adipokines and cardiometabolic risk were tested using Spearman's correlation and logistic regression, adjusted for age and body mass index SD score (BMI-SDS).

RESULTS

Compared to normal weight children; children with overweight/obesity exhibited higher leptin concentrations, lower adiponectin concentrations, and higher L/A ratios. After adjusting for age and degree of obesity, girls with overweight/obesity in the upper quartile range for the L/A ratio, when compared with girls in the lower quartile range, were more likely to have insulin resistance (odds ratio [OR]: 7.78 [95% confidence interval [CI], 3.78-16.65]), dysglycemia (OR: 3.08 [95% CI, 1.35-7.31]), and dyslipidemia (OR: 2.53 [95% CI, 1.18-5.59]); while boys were more likely to have insulin resistance (OR: 4.45 [95% CI, 2.03-10.10]).

CONCLUSIONS

Independent of the degree of obesity, leptin, adiponectin, and the L/A ratio were associated with insulin resistance and other cardiometabolic comorbidities in children with overweight/obesity, but the L/A ratio exhibited stronger associations than the respective adipokines.

Hidradenitis suppurativa in a cohort of overweight and obese children and adolescents

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic, inflammatory, and recurring disease mainly observed in adults. Obesity is considered an important independent factor in HS development and is associated with a higher prevalence of HS in children. We aimed to characterize the clinical presentation of HS in overweight and obese children and adolescents.

METHODS

We performed a cross-sectional observational study during January 2007-April 2015. Overweight and obese patients (5-17 years of age, BMI> 90th percentile) referred to The Children's Obesity Clinic, Department of Paediatrics, Copenhagen University Hospital Holbaek, Denmark, underwent screening for dermatological conditions. A dermatologist ascertained the diagnosis of HS, and disease severity was assessed using Hurley staging and Sartorius score. Tobacco smoke exposure, body mass index (BMI) standard deviation score (SDS), and psychiatric comorbidities were recorded. Our cohort was compared with a reference cohort recruited in a previous study.

RESULTS

A total of 195 children and adolescents underwent screening for dermatological conditions. Nine patients screened positive, and six of these patients were available for examination of whom five presented with HS. All HS cases were mild (median Sartorius score of 9). Four of the five patients (with varying constellations) reported tobacco exposure, a positive family history of HS, and exhibited psychiatric comorbidities.

CONCLUSION

Our findings support that the presence of pediatric HS is correlated with familial disposition to HS and psychiatric comorbidities.

Associations between thyroid-stimulating hormone, blood pressure and adiponectin are attenuated in children and adolescents with overweight or obesity

Background The association between thyroid-stimulating hormone (TSH) concentrations and blood pressure is well described in adults, but only studied to a limited extent in children and adolescents and almost entirely in population-based cohorts. The present study investigates the association between TSH and blood pressure, and the influence of leptin and adiponectin, in a cohort of children and adolescents enrolled in obesity treatment compared with a population-based cohort. Methods We studied 4154 children and adolescents aged 6-18 years from an obesity clinic cohort and a population-based cohort from The Danish Childhood Obesity Data- and Biobank. Anthropometrics, blood pressure and biochemical markers, including TSH, leptin and adiponectin concentrations, were collected. Adjusted correlation and interaction analyses were performed. Results Patients from the obesity clinic cohort exhibited higher concentrations of TSH and higher blood pressure than participants from the population-based cohort. TSH standard deviation scores (SDS) were significantly associated with all blood pressure-related variables in the population-based cohort, but only with systolic blood pressure SDS and hypertension in the obesity clinic cohort. The interaction between TSH SDS and adiponectin was found to be independently associated with systolic blood pressure and hypertension in the population-based cohort only. Conclusions The significant associations between TSH, adiponectin and blood pressure, observed in children and adolescents from a population-based cohort, are attenuated or absent in children and adolescents with overweight or obesity, suggesting that childhood obesity distorts the healthy interplay between the thyroid axis, thyroid-adipokine interaction and blood pressure.

Age-Related Alterations of Nonalcoholic Steatohepatitis in Sprague-Dawley Rats Fed a High-Fat and High-Cholesterol Diet

Nonalcoholic steatohepatitis (NASH), a subtype of nonalcoholic fatty liver disease (NAFLD), has a potentially progressive course that can lead to liver cirrhosis. Age is strongly associated with the development and progression of NAFLD/NASH, but the natural history of pediatric NAFLD is still not fully understood. Here, we evaluated the age-related alterations of NASH in 5-, 9- and 13-wk-old male Sprague-Dawley rats that were fed a high-fat and high-cholesterol diet (30% fat, 1.25% cholesterol and 0.5% sodium cholate, w/w) for 9 wk (6 rats/group). Our results showed that the cumulative energy intake, body weight gain and food efficacy during the 9-wk rearing period were highest in the youngest group and lowest in the oldest group. Serologically, almost all parameters including the serum triglyceride and total cholesterol were similar regardless of age. Histopathological findings, such as hepatic steatosis, lobular inflammation and hepatocyte ballooning, were also similar regardless of age, but hepatic fibrosis was more evident in the oldest group. Also, the mRNA expression levels of some fibrogenic, inflammatory, oxidative stress and cholesterol or lipid metabolism-related genes in the liver were highest in the oldest group and lowest in the youngest group, although the difference was not statistically significant. These results indicated that aging is likely associated with the development of NASH. Because the cumulative energy intake and daily food intake/body weight were not similar among groups in the present study, further studies designed with an equivalent daily food intake/body weight among groups are needed in order to interpret the exact nutritional effect.

Glucose metabolism in children and adolescents: Population-based reference values and comparisons to children and adolescents enrolled in obesity treatment

BACKGROUND

Alterations in glucose metabolism that lead to the development of metabolic and cardiovascular disease may begin already in childhood.

OBJECTIVE

This study aims to generate pediatric age and sex-specific reference values for fasting concentrations of glucose, hemoglobin A1c (HbA1c), insulin, C-peptide, and homeostasis model assessment: insulin resistance (HOMA-IR) in Danish/North-European white children and adolescents from a population-based cohort and to compare values from children and adolescents with overweight/obesity with this reference.

METHODS

The population- and obesity clinic-based cohorts consisted of 2451 and 1935 children and adolescents between 6 and 18 years of age. Anthropometric measurements and blood samples were obtained and percentile curves were calculated.

RESULTS

In the population-based cohort, glucose, insulin, and HOMA-IR values increased before the expected onset of puberty (P < .05). Thereafter, all variables decreased in girls (P < .05) and HbA1c decreased in boys (P < .05). Concentrations of all measured markers of glucose metabolism were higher in the obesity clinic-based cohort than the population-based cohort (both sexes P < .001). Specifically, insulin and HOMA-IR continued to increase to 18 years in the clinic-based cohort, particularly among boys.

CONCLUSIONS

Fasting glucose, insulin, and HOMA-IR change during childhood, making pediatric reference values essential for timely identification of derangements in glucose metabolism. Children and adolescents with obesity exhibit increased concentrations of these biomarkers.

Evaluation of reference intervals of haematological and biochemical markers in an Austrian adolescent study cohort

Background Reference intervals are a prerequisite for the interpretation of laboratory data related to diagnostic issues and treatment strategies. In adolescents, biomarker concentrations change with age, necessitating a continuous age-related definition of the reference intervals. The purpose of this pilot study was to evaluate the reference intervals for a healthy population of adolescents in Salzburg and compare these, when possible, with age- and gender-matched published data. Methods Anthropometrical parameters and blood samples were collected from adolescents (male and female; 14-17 years) in a school setting. Haematological samples were measured using Sysmex XS-1000i, lipid and carbohydrate metabolism markers as well as enzymes and hormones were determined by Cobas c311, Vitros ECiQ® or ELISA. The reference intervals were calculated according to the CLSI guidelines C28-A3c. Results Samples of 102 participants were included. Compared to age- and gender-matched reference intervals, the BMI levels were in the lower normal rage. Most haematological parameters and biomedical makers reveal similar ranges to values published in other studies. Conclusions This data analysis allowed for a partial comparison of reference values with published data and enabled a new determination of paediatric reference intervals for an Austrian cohort.

Reference values for fasting serum concentrations of thyroid-stimulating hormone and thyroid hormones in healthy Danish/North-European white children and adolescents

Thyroid-stimulating hormone (TSH) and thyroid hormones influence the functions of many organ systems, as well as child development and growth. Several studies have reported an association between ethnicity and thyroid hormones. This study aims to explore pediatric serum concentrations of TSH, free triiodothyronine (fT3), and free thyroxine (fT4) and their relation to age and sex and subsequently to present pediatric reference intervals from healthy Danish/North-European white children. A population-based cohort in Denmark of 2411 (1435 girls) healthy school children and adolescents aged 6.0-18.9 years were included. Fasting concentrations of serum TSH, fT3, and fT4 were determined from venous blood samples using immunologic chemiluminescent assays. Age- and sex-dependent percentiles were generated using the GAMLSS function. Median values of fT3 and fT4, but not TSH, were lower in the older age group compared with the youngest age group for both sexes (all p < .05). A significant difference for fT3 was found between the sexes for all age groups (all p < .001). fT4 was negatively correlated with body mass index standard deviation scores in boys. In conclusion, serum concentrations of thyroid hormones vary during childhood and adolescence and differ with age and sex.

Leptin and Adiponectin as markers for preeclampsia in obese pregnant women, a cohort study

OBJECTIVE

Preeclampsia (PE) is a serious complication of pregnancy, the pathogenesis of which is largely unknown. We hypothesize that adipocytokines may play a role in the pathogenesis of PE, particularly in obese women, and evaluate leptin and adiponectin as potential first trimester markers for predicting PE.

STUDY DESIGN

A cohort of 2503 pregnancies, containing 93 PE pregnancies, was divided into women with normal weight, moderate, or severe obesity. All pregnancies had serum adiponectin and leptin measured in first trimester. Logistic regression was used to model PE with maternal characteristics and concentrations of the biomarkers.

RESULTS

In obese women a lower concentration of adiponectin was found in PE pregnancies; the concentration was lowest in the severely obese (p = 0.005). No association was found in normal weight women (p = 0.72). Leptin concentration had no association with PE in normal weight and moderately obese (p = 0.175-0.072), however in women with severe obesity a lower level of leptin was found (p = 0.049). The AUC was 0.73 for the ROC curve of combined maternal characteristics and adiponectin. Using adiponectin in women with moderate to severe obesity the sensitivity was 72.9% and the specificity was 49%.

CONCLUSIONS

In severely obese women, PE is associated with low serum adiponectin and leptin concentrations in first trimester. This indicates that the inability of adipokine regulation to adapt to severe obesity may play a role in the pathogenesis of PE. Adipocytokines may contribute in identification of risk pregnancies among severe obese.

Adiponectin levels in Brazilian adolescents: Distribution and associated factors in ERICA survey

BACKGROUND

The aim of this study was to evaluate the distribution of adiponectin and associated factors with low adiponectin levels in a large sample of adolescents from different Brazilian regions.

METHODS

This is a national, school-based, cross-sectional multicenter study of cardiovascular risk factors in Brazilian adolescents aged 12 to 17 years. Serum adiponectin levels (μg/ml) were measured by enzyme-linked immunosorbent assay kit. Given the lack of reference values, sex-and age-specific median was adopted as the cutoff point, with the values below the median representing a higher-risk profile. Associated factors with low levels of adiponectin were investigated using Poisson regression.

RESULTS

The sample consisted of 4546 adolescents, the majority female (61.2%). The prevalence of overweight/obesity and abdominal obesity was 30% and 13.4%, respectively. The medians of adiponectin were 13.4 μg/ml (95%CI: 12.8-14.0) in males and 14.2 μg/ml (95%CI: 13.3-15.0) in females. Lower adiponectin levels were associated with both overweight (Prevalence Ratios (PR) = 1.17; 95%CI 1.01-1.36) and obesity (PR = 1.36; 95%CI 1.16-1.56) in males, while, in females, adiponectin levels were associated only with obesity (PR = 1.45; 95% CI 1.26-1.66). Increased waist circumference in both males and females was inversely associated with adiponectin level.

CONCLUSIONS

Adiponectin levels were lower among adolescents with weight excess and abdominal obesity. Male adolescents who live in rural areas and study at private schools also showed lower adiponectin concentrations.

Adiponectin and leptin as first trimester markers for gestational diabetes mellitus: a cohort study

BACKGROUND

Gestational diabetes mellitus (GDM) is increasing partly due to the obesity epidemic. Adipocytokines have thus been suggested as first trimester screening markers for GDM. In this study we explore the associations between body mass index (BMI) and serum concentrations of adiponectin, leptin, and the adiponectin/leptin ratio. Furthermore, we investigate whether these markers can improve the ability to screen for GDM in the first trimester.

METHODS

A cohort study in which serum adiponectin and leptin were measured between gestational weeks 6+0 and 14+0 in 2590 pregnant women, categorized into normal weight, moderately obese, or severely obese.

RESULTS

Lower concentrations of adiponectin were associated with GDM in all BMI groups; the association was more pronounced in BMI<35 kg/m2 (p=0.30 for interaction). Leptin was inversely associated with GDM in severely obese (p=0.033), but showed no association in women with BMI<35 kg/m2. The adiponectin/leptin ratio was associated with GDM in women with BMI<35 kg/m2 but not in severely obese women (p=0.79). In regard to predicting GDM, maternal characteristics combined with adiponectin alone, adiponcetin and leptin, and adiponcetin/leptin ratio had the strongest associations in women with BMI<35 kg/m2. These models had a detection rate of 77.3%-80.3% when the false positive rate was fixed at 25%.

CONCLUSIONS

Low adiponectin measured in the first trimester is associated with the development of GDM; higher BMI was associated with lower performance of adiponectin, though this was insignificant. Leptin had an inverse relationship with GDM in severely obese women and did not improve the ability to predict GDM.

Adiponectin profile and Irisin expression in Italian obese children: Association with insulin-resistance

Adiponectin (Acrp30), its high molecular weight (HMW) oligomers, and Irisin are molecules involved in several metabolic processes. To investigate if these cytokines could represent new metabolic markers, we evaluated the expression of Acrp30 and Irisin in serum of obese children from South Italy affected by different degrees of insulin resistance (IR). The anthropometric and metabolic features were evaluated in 27 obese children versus 13 age-matched controls. The expression of Acrp30, its pattern and Irisin were investigated by ELISA, western blotting and fast protein liquid chromatography. The HOMA index was significantly higher in obese children versus controls, and metabolic syndrome was more prevalent in obese children with elevated IR versus those with normal HOMA (38% vs 16%). Total Acrp30 and HMW oligomers were significantly lower in obese than in control children, and the difference was more pronounced in children with HOMA >3.4. In control and obese children, total Acrp30 and HMW oligomers were inversely related to HOMA (r-0.38, p 0.02; r-0.35, p 0.03). Irisin was significantly higher in obese than in control children, and was inversely correlated with Acrp30 and HMW (r-0.32, p 0.04; r-0.39, p 0.01). The inverse correlation of Acpr30 and HMW oligomers with HOMA indicates that Acpr30 is directly involved in IR status. Moreover, the inverse correlation between Irisin and Acrp30 and, more significantly, between Irisin and HMW oligomers suggests that the two cytokines are closely connected. The use of Acrp30, HMW oligomers and Irisin as predictive factors of IR in obese children remains to be further elucidated.

Endogenous and exogenous factors influencing the concentrations of adiponectin in body fluids and tissues in the bovine

Adiponectin, one of the messenger molecules secreted from adipose tissue that are collectively termed adipokines, has been demonstrated to play a central role in lipid and glucose metabolism in humans and laboratory rodents; it improves insulin sensitivity and exerts antidiabetic and antiinflammatory actions. Adiponectin is synthesized as a 28 kDa monomer but is not secreted as such; instead, it is glycosylated and undergoes multimerization to form different molecular weight multimers before secretion. Adiponectin is one of the most abundant adipokines (μg/mL range) in the circulation. The concentrations are negatively correlated with adipose depot size, in particular with visceral fat mass in humans. Adiponectin exerts its effects by activating a range of different signaling molecules via binding to 2 transmembrane receptors, adiponectin receptor 1 and adiponectin receptor 2. The adiponectin receptor 1 is expressed primarily in the skeletal muscle, whereas adiponectin receptor 2 is predominantly expressed in the liver. Many of the functions of adiponectin are relevant to growth, lactation, and health and are thus of interest in both beef and dairy production systems. Studies on the role of the adiponectin protein in cattle have been impeded by the lack of reliable assays for bovine adiponectin. Although there are species-specific bovine adiponectin assays commercially available, they suffer from a lack of scientific peer-review of validity. Quantitative data about the adiponectin protein in cattle available in the literature emerged only during the last 3 yr and were largely based on Western blotting using either antibodies against human adiponectin or partial peptides from the bovine sequence. Using native bovine high-molecular-weight adiponectin purified from serum, we were able to generate a polyclonal antiserum that can be used for Western blot but also in an ELISA system, which was recently validated. The objective of this review is to provide an overview of the literature about the adiponectin protein in cattle addressing the following aspects: (1) the course of the adiponectin serum concentrations during development in both sexes, during inflammation, nutritional energy deficit and energy surplus, and lactation-induced changes including the response to supplementation with conjugated linoleic acids and with niacin, (2) the concentrations of adiponectin in subcutaneous vs visceral fat depots of dairy cows, (3) the protein expression of adiponectin in tissues other than adipose, and (4) the concentrations in different body fluids including milk.