Waist-to-height ratio, inflammation and CVD risk in obese children

Childhood Cardiovascular Health, Obesity, and Some Related Disorders: Insights into Chronic Inflammation and Oxidative Stress

Childhood obesity and associated metabolic abnormalities have become pressing public health concerns worldwide, significantly impacting cardiovascular health. Metabolic syndrome, characterized by a cluster of metabolic abnormalities including central obesity, altered glucose metabolism, dyslipidemia, and arterial hypertension, has emerged as a critical precursor to cardiovascular disease. Chronic systemic inflammation and oxidative stress seem to play pivotal roles in the pathogenesis of childhood obesity-related disorders such as early atherosclerosis. A significant distinction between the objective components of cardiovascular health metrics, including body mass index, blood pressure, cholesterol, and fasting glucose levels, and the definition of metabolic syndrome is evident in the identification of obesity. Whereas cardiovascular health metrics predominantly rely on body mass index percentiles to assess obesity, metabolic syndrome criteria prioritize waist circumference, specifically targeting individuals with a measurement ≥90th percentile. This discrepancy emphasizes the need for a nuanced approach in assessing the risks associated with obesity and underscores the importance of considering multiple factors when evaluating cardiovascular risk in children. By recognizing the complex interplay between various health metrics, obesity and metabolic syndrome criteria, clinicians can more accurately identify individuals at risk and tailor interventions accordingly to mitigate cardiovascular disease in children with obesity.

Appraisal of Clinical Care Practices for Child Obesity Treatment. Part II: Comorbidities

The objective of this technical report is to provide clinicians with actionable evidence-based information upon which to make treatment decisions. In addition, this report will provide an evidence base on which to inform clinical practice guidelines for the management and treatment of overweight and obesity in children and adolescents. To this end, the goal of this report was to identify all relevant studies to answer 2 overarching key questions: (KQ1) "What are effective clinically based treatments for obesity?" and (KQ2) "What is the risk of comorbidities among children with obesity?" See Appendix 1 for the conceptual framework and a priori Key Questions.

Longitudinal associations between cardiovascular biomarkers and metabolic syndrome during puberty: the PUBMEP study

Puberty has been described as a life stage of considerable metabolic risk specially for those with obesity. The low-grade systemic inflammatory status associated with obesity could be one of the connections with metabolic syndrome (MetS). Thus, we aimed to assess the relationship between inflammatory and cardiovascular biomarkers and the development of MetS during puberty. Seventy-five children from the PUBMEP study (33 females), aged 4-18 years, were included. Cardiovascular and inflammatory biomarkers were measured in the prepubertal and pubertal stage, including high-sensitivity C-reactive protein (CRP), leptin, tumor necrosis factor-alpha (TNFα), interleukin 8 (IL8), monocyte chemoattractant protein 1 (MCP-1), total plasminogen activator inhibitor-1 (tPAI), resistin, adiponectin, myeloperoxidase (MPO), and soluble intercellular adhesion molecule-1 (sICAM-1). MetS was diagnosed at each measurement point. Mixed-effects and logistic regressions were performed. Those children with MetS in puberty presented higher prepubertal values of several cardiometabolic biomarkers in comparison to those without MetS (z-score body mass index (zBMI), waist circumference, insulin, HOMA-IR, leptin, and tPAI (p < 0.05)). For prepubertal children with obesity, the odds of developing MetS in puberty were significantly higher in those having high zBMI (OR = 4.27; CI: 1.39-22.59) or high concentrations of tPAI (OR = 1.19; CI: 1.06-1.43).

CONCLUSION

Those with obesity with higher prepubertal tPAI plasma levels had 19% higher odds of having MetS at puberty highlighting the existence of association between MetS, obesity, and inflammation already in puberty. Thus, assessing cardiometabolic and inflammatory status in children with obesity already at prepuberty is key to avoiding future comorbidities.

WHAT IS KNOWN

• Inflammation, metabolic syndrome, and obesity may have their onset in childhood. • Puberty is a life stage characterized for an increased cardiovascular risk.

WHAT IS NEW

• Prepuberty state could be an early indicator of future cardiometabolic risk. • Children with obesity and high total plasminogen have higher odds of future metabolic syndrome.

Waist-to-height ratio cut-off points to predict obesity in adolescents and associa-tion with inflammatory markers

Introduction

Introduction: obesity increases inflammatory molecules and cardiovascular risk even in young populations. New indicators are being investigated, including the waist-to-height ratio (WHtR) to predict obesity and the relationship with inflammatory markers in childhood and adolescence. Objective: to identify the cut-off points of the WHtR to determine obesity and its association with inflammatory markers in adolescents in São Luís, state of Maranhão, Brazil. Methods: this is a cross-sectional study, with 2,209 adolescents aged 18 and 19, belonging to the third phase of the birth cohort entitled "RPS", carried out in 2016. The total area under the ROC curve (AUC) was identified to assess the predictive capacity of WHtR in relation to body fat percentage (%BF), obtained by air displacement plethysmography (ADP). The association of WHtR with inflammatory markers interleukin-6 (IL-6), tumor necrosis factor (TNF-α) and c-reactive protein (CRP) was evaluated. Results: prevalence of obesity by the %BF was 10.3 % in males and 40.4 % in females. The cut-off points for the WHtR were 0.50 for females and 0.51 for males, with an AUC of 0.90 (95 % CI: 0.88-0.92) and 0.93 (95 % CI: 0.90-0.97). There was an association of elevated WHtR with higher levels of IL-6 and CRP (p < 0.05). Conclusion: the predictive capacity of WHtR for obesity was excellent. Elevated values of the WHtR were associated with early inflammatory markers. This study contributed to the identification of cut-off points for simple and low-cost anthropometric indicators.

Catalase post-translational modifications as key targets in the control of erythrocyte redox homeostasis in children with obesity and insulin resistance

Insulin resistance (IR) is the most common metabolic disturbance in children with obesity. Children with obesity and insulin resistance (ObIR+) display a detriment in erythroid antioxidant defenses, caused by an impaired catalase activity and the increase in oxidative and pro-inflammatory markers. Therefore, erythrocytes from ObRI+ are more vulnerable to any oxidative stress elicitor. Since catalase is one of the erythrocytes' first antioxidant defenses, we intended to delve into the mechanisms underlying catalase's impaired activity. Given the lack of cellular organelles in erythrocytes, which prevents protein synthesis, we aimed study catalase post-translational modifications (PTMs) as targets of pro-inflammatory and pro-oxidant status of these cells in children with obesity and IR. Catalase levels of O-glycosylation, tyrosine nitration and S-glutathionylation were analyzed by Western blotting (WB) using immunoprecipitated catalase (IP-CAT) from erythrocyte lysates. Furthermore, Catalase was also identified by LC-MS/MS after isolation and enrichment of erythrocyte nitrosated proteins with a biotin switch approach. The results obtained suggest that catalase inhibition seen in children with obesity is partly due to the increase in the S-nitrosation of the enzyme. Indeed, exogenous administration of nitric oxide (NO) to cultured erythrocytes resulted in a decrease in catalase activity in all groups. Signals of other PTMs (O-glycosylation, Tyr-nitration and S-glutathionylation) were also detected in the erythrocyte catalase in every groups, although levels of catalase O-glycosylation and S-glutathionylation decreased in ObIR+. No evidence of differences in Tyr-nitration of catalase levels were found among groups. The study again highlights the role of erythrocytes as sensors of the inflammatory and pro-oxidant response to which these cells are subjected in children with obesity and insulin resistance.

Impact of One-Year Dietary Education on Change in Selected Anthropometric and Biochemical Parameters in Children with Excess Body Weight

Obesity is regarded as a civilization disease that increases mortality and the risk of cardiovascular complications. In Poland, the prevalence of excess body weight in the paediatric population has been steadily increasing. The consequences of excess body weight in the developmental age population affect children's health and destabilize their development. Appropriate dietary interventions are the main non-invasive methods of preventing and treating obesity. They should be aimed at the whole family, optimally with the use of simple tools such as the Healthy Eating Pyramid. Due to the increasing prevalence of excess body weight in the developmental age population and the problems with the treatment of this condition, studies were undertaken in order to determine the impact of a dietary intervention on anthropometric and biochemical parameters in children with excess body weight. A total of 68 (72.3%) children completed the study. Based on BMI SDS, 59 (86.8%) were diagnosed with obesity and 9 (13.2%) with overweight. After the completion of the one-year dietary educational program, a significant improvement in weight loss, waist and hip circumference, as well as the value of the WHtR index was demonstrated. There was also a significant increase in the percentage of muscle tissue and a decrease in the content of adipose tissue in the bodies of examined children. A significant improvement in the parameters of carbohydrate metabolism, and almost all parameters of lipid metabolism, except for total cholesterol. A significant (by 28.0%) reduction in the incidence of fatty liver was also noted. No influence of dietary education on arterial blood pressure was observed.

Fitness Levels and Gender Are Related With the Response of Plasma Adipokines and Inflammatory Cytokines in Prepubertal Children

Background and Aim

Changes in adipokines have been related with the development of metabolic syndrome, frequently associated with obesity, and other risk factors. Fitness seems to promote a healthy cardiovascular status and could be a protector factor, just from childhood. Therefore, the present study aimed to evaluate the relationship between fitness levels with plasma adipokines and inflammatory biomarkers in prepubertal children.

Methods

One hundred and thirty-seven healthy normal-weight prepubertal children were recruited from local schools and divided after performing the fitness tests, into two groups according to fitness level—low cardiovascular fitness group (LF) and equal or higher cardiovascular fitness group (HF). Anthropometric variables, blood pressure (BP) and plasma insulin, and leptin, resistin, adiponectin, tumor necrosis factor-alpha, hepatic growth factor, interleukin (IL)-8, monocyte chemoattractant protein-1, nerve growth factor (NGF), and plasminogen activator inhibitor-1 (PAI-1) were measured fasting in both groups to be compared. Univariate analysis of variance, comparative analysis, binary logistic regression, stepwise linear regression, and principal component analysis were conducted to evaluate the association between fitness, BMI, gender, and the biochemical parameters.

Results

Girls and boys with HF presented lower waist circumference Z-score, BMI Z-score, systolic BP (only boys) as well as lower levels of leptin and NGF compared with their respective LF group. Regarding the association between variables, fitness showed an inverse relationship with BMI Z-score, leptin, PAI-1, HOMA-IR, resistin, IL-8, and NGF.

Conclusion

An adequate level of fitness seems to protect against risk factors related to low-grade inflammation and altered adipokines that are related to the onset of obesity just from the prepubertal stage.

Causative Mechanisms of Childhood and Adolescent Obesity Leading to Adult Cardiometabolic Disease: A Literature Review

The past few decades have shown a worrisome increase in the prevalence of obesity and its related illnesses. This increasing burden has a noteworthy impact on overall worldwide mortality and morbidity, with significant economic implications as well. The same trend is apparent regarding pediatric obesity. This is a particularly concerning aspect when considering the well-established link between cardiovascular disease and obesity, and the fact that childhood obesity frequently leads to adult obesity. Moreover, most obese adults have a history of excess weight starting in childhood. In addition, given the cumulative character of both time and severity of exposure to obesity as a risk factor for associated diseases, the repercussions of obesity prevalence and related morbidity could be exponential in time. The purpose of this review is to outline key aspects regarding the current knowledge on childhood and adolescent obesity as a cardiometabolic risk factor, as well as the most common etiological pathways involved in the development of weight excess and associated cardiovascular and metabolic diseases.

Impact of Physical Activity Intensity Levels on the Cardiometabolic Risk Status of Children: The Genobox Study

Childhood obesity has been related to metabolic syndrome and low-grade chronic inflammation. This study aimed to evaluate the impact of physical activity intensities and practice on inflammation, endothelial damage, and cardiometabolic risk factors in children. There were 513 participants, aged 6-14 years, recruited for the study. Physical activity was measured by accelerometry, and the children were classified into four groups according to quartiles of moderate to vigorous physical activity (MVPA) practice as very low active, low active, moderate active, and high active. Anthropometric measures, blood pressure, and plasma metabolic and proinflammatory parameters were analyzed. Very low active group presented a worse lipid profile and higher insulin, leptin, adiponectin, resistin, matrix metallopeptidase-9, and tissue plasminogen activator inhibitor-1, while lower levels of tumor necrosis factor-alpha, Type 1 macrophages, and interleukin 8 than high-active children. Regression analyses showed that a higher MVPA practice was associated with lower levels of triacylglycerols (β: -0.118; p = .008), resistin (β: -0.151; p = .005), tPAI (β: -0.105; p = .046), and P-selectin (β: -0.160; p = .006), independently of sex, age, and body mass index (BMI). In contrast, a higher BMI was associated with higher levels of insulin (β: 0.370; p < .001), Homeostasis Model Assessment (β: 0.352; p < .001), triacylglycerols (β: 0.209; p < .001), leptin (β: 0.654; p < .001), tumor necrosis factor-alpha (β: 0.182; p < .001), Type 1macrophages (β: 0.181; p < .001), and tissue plasminogen activator inhibitor (β: 0.240; p < .001), independently of sex, age, and MVPA. A better anthropometric, metabolic, and inflammatory profile was detected in the most active children; however, these differences were partly due to BMI. These results suggest that a higher MVPA practice and a lower BMI in children may lead to a better cardiometabolic status.

Is Office Blood Pressure Measurement Reliable in Obese Adolescents?

BACKGROUND

Although it is not reflected in the OBP measurement in obese children, ambulatory BP changes are known to occur. MH, non-dipper pattern and nocturnal hypertension have been reported to increase in obese children. On the other hand, the factors that indicate a high risk of hypertension are still unclear. The aim of our study is to especially detect masked hypertension by 24-hour BP measurement in obese adolescents and to evaluate the relationship of masked hypertension with metabolic syndrome parameters, anthropometric measurements and hepatosteatosis in these patients.

METHODS

A total of 63 adolescents diagnosed with obesity were evaluated between January 2019 and December 2019. Office blood pressure was measured for all children, and all of them underwent ABPM. Patients with and without hypertension in ABPM were compared in terms of clinical and laboratory findings.

RESULTS

The mean age was 14.0 ± 1.7 years, females composed 49.2% of the study population. Office blood pressure measurement revealed hypertension in 4 (6.3%) patients and prehypertension in 15 (23.8%) patients. Thirteen patients (20.9%) were diagnosed with masked hypertension, white coat hypertension was diagnosed in 3 (4.7%) patients. Abnormal ABPM patterns were found to be significantly more frequent in patients with severely obesity (with obesity: 26.4% vs severe obesity: 55.6%, p = 0.03) and patients with a higher waist circumference and waist circumference/height ratio.

CONCLUSION

The prevalence of masked hypertension in obese adolescents has been found to be quite high. Therefore, we recommend ABPM in adolescents with high waist circumference/height ratio and severe obesity, even if their office blood pressure measurements are normal.

Integrative Analysis of Lipid Profiles in Plasma Allows Cardiometabolic Risk Factor Clustering in Children with Metabolically Unhealthy Obesity

Hypertension, central obesity, hyperglycemia, and dyslipidemia are key risk factors for cardiovascular disease. However, the specific factors contributing to the development of unfavorable cardiometabolic characteristics in children with obesity are unknown. In this study, we investigated the cross-sectional relationships between cytokines, irisin, and fatty acid (FA) composition in plasma in school-age children with metabolically healthy and unhealthy obesity (MHO and MUO, respectively) of the same age and body mass index and waist circumference percentiles. We compared the data with that of children with normal weight (NW). We found that inflammatory cytokines and low irisin plasma concentrations are associated with obesity but not with cardiometabolic risk (CMR). Lipid profiles showed that children with MUO have a distinctive FA profile compared with children with MHO and NW, whereas children with MHO shared 88% of the FA profile with the NW group. Among all FAs, concentration of myristic acid (14 : 0), arachidic acid (20 : 0), and n-3 polyunsaturated FAs (PUFAs) was higher in children with MHO, whereas n-6 PUFAs such as arachidonic acid (20 : 4n6) had a significant contribution in defining MUO. These data suggest that the plasma FA profile is not only a central link to obesity but also may act as an indicator of CMR presence.

Differences in Neuregulin 4 Expression in Children: Effects of Fat Depots and Obese Status

PURPOSE

To observe the expression of Nrg4, uncoupling protein-1 (UCP1), tumor necrosis factor α (TNFα), CD31, VE-cadherin/CDH5 and vascular endothelial growth factor A (VEGF-A) mRNA in abdominal subcutaneous (SC), omental (OM) adipose tissue in children with relation to anthropometric parameters. Further to verify the effect of inflammatory mediators on Nrg4 and UCP1 mRNA expression in adipocytes.

METHODS

Paired SC and OM adipose tissues were obtained from 58 children. In vitro, the adipocytes isolated from primary inguinal adipose tissue of mice were treated with TNFα (50 ng/ml) for 12-48 h. mRNA levels of Nrg4, UCP1 and TNFα were determined by real-time PCR.

RESULTS

Nrg4, UCP1, VEGF-A and CDH5 mRNA levels in SC were significantly higher than those in OM adipose tissue and the mRNA level of TNFα showed the opposite result. Moreover, Nrg4 and UCP1 mRNA in SC were significantly lower in overweight children compared to normal weight children. Nrg4 in SC and OM was negatively associated with BMISDS, WHtR. CDH55 mRNA in OM was negatively associated with WHR. VEGF-A was positively correlated with Nrg4 in SC. In vitro, Nrg4 and UCP1 mRNA levels in adipocytes were dose- and time-dependently decreased under TNFα treatment.

CONCLUSIONS

Nrg4, UCP1, VEGF-A and CDH5 mRNA expression in adipose tissues display a depot-specific pattern. Nrg4 mRNA levels in adipose tissue are decreased with obesity and associated with WAT browning and angiogenesis. TNFα may be involved in the regulation of Nrg4 level in adipose tissue, which may be one of the causes of the down-regulation of Nrg4 expression in obesity with chronic inflammatory response.

Anthropometric and Biochemical Markers as Possible Indicators of Left Ventricular Abnormal Geometric Pattern and Function Impairment in Obese Normotensive Children

Εmerging data indicate that various effects of obesity on the cardiovascular system can be evident during childhood. The aim of this study was to detect early changes in left ventricular structure and function in obese normotensive children and explore possible associations of these changes with anthropometric and biochemical parameters. Normotensive 8–11-year-old obese and normal weight children were included in the study. They all underwent anthropometric measurements, laboratory tests, and echocardiography study by conventional and tissue Doppler to assess geometric pattern and function of left ventricle. Statistically significant differences in most anthropometric and metabolic parameters were noticed between groups. Obese children showed higher left ventricular mass index (LVMI) (40.05 ± 9.44 vs. 28.31 ± 6.22), lower E/A ratio (1.76 ± 0.33 vs. 2.08 ± 0.56), and higher E/e’ (6.04 ± 1.13 vs. 5.43 ± 0.96) compared to lean peers. Waist-to-height ratio and hs-CRP correlated significantly with E/A in the obese group. Left ventricular hypertrophy was present in 47.2% of obese children and eccentric was the prominent type. Waist-to-height ratio and serum cortisol levels in plasma increased the odds of having any type of abnormal ventricular geometric pattern. Echocardiographic evaluation of left ventricle and diastolic function could be considered for obese normotensive children based on waist-to-height ratio, hs-CRP, and serum cortisol.

Analysis of the chemerin and resistin adipokines in children and adolescents

OBJECTIVES

To compare the serum concentrations of adipokines resistin and chemerin in children and adolescents with eutrophic and overweight and to evaluate their relationship with anthropometric, biochemical, and blood pressure variables.

METHODS

a cross-sectional epidemiological study was conducted with 234 students enrolled in public elementary schools in the city of Juiz de Fora / MG. Anthropometric evaluation, biochemistry, and blood pressure measurement were performed. Statistical analyzes included the Student-t or Mann-Whitney tests, Pearson or Spearman correlation, used according to the distribution of the variables, and linear regression analysis, by means of the evaluation of the effect of the independent variables on the serum levels of chemerin and resistin, adjusted for age and sex. For the data analysis, SPSS® software version 21.0 and STATA® version 10.1 were used, assuming a significance level of 5%.

RESULTS

the concentrations of chemerin were higher in eutrophic individuals than in those with excess weight (p> 0.05). In contrast, levels of resistin were higher in the young with excess weight than in the eutrophic ones (p <0.05). In the multiple linear regression analysis, the levels of chemerin were associated with the values of resistin, systolic, and diastolic blood pressure. Resistance levels maintained association only with BMI and chemerin values.

CONCLUSION

the adipokines analyzed presented a distinct profile in the groups of children and adolescents with eutrophic and overweight.

Myeloperoxidase as cardiovascular risk marker in pre-pubertal preterm children?

BACKGROUND AND AIMS

To evaluate the biomarkers related to cardiovascular risk in pre-pubertal preterm children with a birth weight of less than 1,500 g and relate them to current nutritional status, insulin resistance, and inflammation.

METHODS & RESULTS

This is a cross-sectional, controlled study with pre-pubertal preterm children aged 5-9 years with a birth weight of less than 1500 g (Preterm group, n = 44) compared to full term children of adequate weight for gestational age (Control group, n = 30). Clinical evaluation: anthropometry and pubertal staging. Laboratory tests: total cholesterol and fractions, triglycerides, paraoxonase 1, apolipoproteins A-I and B, myeloperoxidase (MPO), high sensitivity C-reactive protein (hs-CRP), glycemia and insulin (to calculate HOMA-IR). In the preterm group, 19 (43.2%) were male, with mean birth weight and gestational age of 1157 ± 242 g and 30.0 ± 2.3 weeks, respectively. The preterm group showed lower concentrations of HDL-c (60.1 ± 10.1 vs. 69.0 ± 10.0 mg/dL; p < 0.001); higher concentrations of hs-CRP [0.55 mg/dL (0.30; 39.4) vs. 0.30 mg/dL (0.30; 10.80); p = 0.043], of MPO [21.1 ng/mL (5.7; 120.0) vs. 8.1 ng/mL (2.6; 29.6); p < 0.001] and of MPO/HDL-c ratio [0.39 (0.09; 2.07) ng/mg vs. 0.11 (0.05; 0.58)]. The MPO/HDL-c ratio was the variable that showed the best discriminatory power between the groups (AUC = 0.878; 95% CI; 0.795-0.961). MPO concentrations in the preterm group were correlated with those of hs-CRP (r = 0.390; p = 0.009), insulin (r = 0.448; p = 0.002) and HOMA-IR (r = 0.462; p = 0.002).

CONCLUSION

Prepubertal preterm children show high MPO concentrations and MPO/HDL-c ratio that are associated with inflammation and oxidative stress, which, in turn, may be associated with atherosclerosis.

Identifying the relationship between biological, psychosocial and family markers associated with childhood obesity: Case-control "ANOBAS" study

The recent increase in childhood obesity prevalence rates illustrates the extreme relevance of biological, psychosocial and familial factors implicated in body weight status, which at the moment remain unclear. The study aims to compare biological, psychosocial and familial markers between preadolescents with obesity and their non-overweight peers, and explore the relationship with psychiatric diagnosis on these markers. Both groups were composed of 40% of males with a mean age of 10 years, and no differences in socio-demographic variables were found between groups. No sex differences were found on bio/psycho/family markers. While 48% (n = 24) of the preadolescents with obesity presented a DSM-IV diagnosis (OGD), only 2% (n = 1) of the non-overweight peers (NG) met diagnostic criteria. Significant differences were found for all bio/psycho/family markers among obese preadolescents with the exceptions of cortisol, peptide YY and maternal state-anxiety and depression. The preadolescents with obesity without a diagnosis (OGND) presented greater levels of leptin than NG (p = 0.01). For psychosocial markers, statistically significant differences were found between groups in the majority of the variables (p <  0.01), with the exception of trait anxiety where a tendency towards significance was revealed (p = 0.06). For family markers, we found statistically significant differences in emotional over-involvement (p = 0.01), with NG mothers presenting lower scores than OGD and OGND. Include psychosocial and family factors in obesity intervention programs is necessary. Also, health professionals working with children with obesity must take care to assess the presence of a psychiatric diagnosis amongst this population.

Comprehensive identification of pleiotropic loci for body fat distribution using the NHGRI-EBI Catalog of published genome-wide association studies

We conducted a hypothesis-free cross-trait analysis for waist-to-hip ratio adjusted for body mass index (WHR_adjBMI ) loci derived through genome-wide association studies (GWAS). Summary statistics from published GWAS were used to capture all WHR_adjBMI single-nucleotide polymorphisms (SNPs), and their proxy SNPs were identified. These SNPs were used to extract cross-trait associations between WHR_adjBMI SNPs and other traits through the NHGRI-EBI GWAS Catalog. Pathway analysis was conducted for pleiotropic WHR_adjBMI SNPs. We found 160 WHR_adjBMI SNPs and 3675 proxy SNPs. Cross-trait analysis identified 239 associations, of which 100 were for obesity traits. The remaining 139 associations were filtered down to 101 unique linkage disequilibrium block associations, which were grouped into 13 categories: lipids, red blood cell traits, white blood cell counts, inflammatory markers and autoimmune diseases, type 2 diabetes-related traits, adiponectin, cancers, blood pressure, height, neuropsychiatric disorders, electrocardiography changes, urea measurement, and others. The highest number of cross-trait associations were found for triglycerides (n = 10), high-density lipoprotein cholesterol (n = 9), and reticulocyte counts (n = 8). Pathway analysis for WHR_adjBMI pleiotropic SNPs found immune function pathways as the top canonical pathways. Results from our original methodology indicate a novel genetic association between WHR_adjBMI and reticulocyte counts and highlight the pleiotropy between abdominal obesity, immune pathways, and other traits.

Decreased serum neuregulin 4 levels associated with non-alcoholic fatty liver disease in children with obesity

Neuregulin 4 (Nrg4), a newly identified adipokine secreted by brown adipose tissue, is hypothesised to play a crucial role in metabolism. The present study aimed to evaluate the association between serum Nrg4 levels and non-alcoholic fatty liver disease (NAFLD) in children with obesity in China. A total of 123 children with obesity were included in this study. Anthropometric and biochemical parameters were measured in all subjects. NAFLD was diagnosed using ultrasonography. The serum levels of Nrg4, leptin and adiponectin were measured by enzyme-linked immunosorbent assay. NAFLD was identified in 58 children with obesity (47.2%). Serum Nrg4 levels were significantly lower in the NAFLD group (2.24 [1.20, 3.22] ng/mL) than in the control group (5.50 [2.45, 10.85] ng/mL) (p < 0.001). Serum Nrg4 levels were negatively correlated with most of the anthropometric and biochemical parameters (p < 0.05) but were positively correlated with high-density lipoprotein cholesterol (p < 0.05). In multiple stepwise regression analyses, serum Nrg4 levels were independently related with WHtR (β = -2.009, p = 0.048) and homeostasis model assessment of insulin resistance (β = -0.524, p = 0.005). Furthermore, a multivariable logistic regression analysis of NAFLD prediction by Nrg4 revealed an odds ratio of 0.129 (95% confidence interval: 0.028-0.587, p < 0.01). The receiver operating characteristic curve analysis of the diagnostic value of using serum Nrg4 levels to differentiate NAFLD in children with obesity showed that the area under the curve was 0.723; the cutoff for serum Nrg4 levels to have diagnostic value for predicting NAFLD in children with obesity was 3.39 ng/mL. Elevated Nrg4 is associated with a decreased risk of NAFLD in children with obesity.

Cardiovascular risk biomarkers and metabolically unhealthy status in prepubertal children: Comparison of definitions

BACKGROUND AND AIMS

The early onset of cardio-metabolic abnormalities, known as metabolically unhealthy (MU) status, is highly associated with obesity and cardiovascular disease (CVD), as well as with increased morbidity and mortality later in life. Given the lack of a consensus MU classification for prepubertal children, we aimed to compare available MU definitions in terms of their association with CVD risk biomarkers.

METHODS AND RESULTS

A total of 930 prepubertal children (622 with overweight/obesity, 462 males) aged 5-10.9 years were recruited, anthropometric measures were taken and biomarkers were analyzed. Children were classified using eight MU definitions based on different cut-offs for blood pressure, triacylglycerides, high-density lipoprotein cholesterol, glucose and homeostasis model assessment for insulin resistance (HOMA-IR). MU prevalence in children with overweight/obesity ranged between 30% and 60% across definitions. Plasma concentrations of resistin, leptin, myeloperoxidase (MPO) and total plasminogen activator inhibitor 1 (tPAI-1) were higher, and those of adiponectin were lower, in MU compared to MH children with overweight/obesity. Linear regression analyses confirmed the contribution of MPO and tPAI-1 concentrations to MU status, with most significant results derived from definitions that use age and sex-specific criteria and that account for HOMA-IR.

CONCLUSION

Plasma concentrations of MPO and tPAI-1 are increased in prepubertal MU children irrespective of having normal-weight or overweight/obesity. Inclusion of age and sex-specific cut-offs for cardio-metabolic components as well as insulin resistance criteria increases the quality of MU definitions as seen by their stronger association with CVD biomarkers concentrations.

Why monkeys do not get multiple sclerosis (spontaneously): An evolutionary approach

The goal of this review is to apply an evolutionary lens to understanding the origins of multiple sclerosis (MS), integrating three broad observations. First, only humans are known to develop MS spontaneously. Second, humans have evolved large brains, with characteristically large amounts of metabolically costly myelin. This myelin is generated over long periods of neurologic development—and peak MS onset coincides with the end of myelination. Third, over the past century there has been a disproportionate increase in the rate of MS in young women of childbearing age, paralleling increasing westernization and urbanization, indicating sexually specific susceptibility in response to changing exposures. From these three observations about MS, a life history approach leads us to hypothesize that MS arises in humans from disruption of the normal homeostatic mechanisms of myelin production and maintenance, during our uniquely long myelination period. This review will highlight under-explored areas of homeostasis in brain development, that are likely to shed new light on the origins of MS and to raise further questions about the interactions between our ancestral genes and modern environments.

Association between the triglyceride to high-density lipoprotein cholesterol ratio and insulin resistance in Korean adolescents: a nationwide population-based study

BACKGROUND

Studies have suggested the triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-C) as a surrogate marker of insulin resistance. However, few studies have examined the association between TG/HDL-C and insulin resistance in the general adolescent population. This study aimed to examine the association between TG/HDL-C and insulin resistance in a nationally representative sample of Korean adolescents.

METHODS

A total of 2649 participants aged 12-18 years were selected from the 2007 to 2010 Korean National Health and Nutrition Examination Survey (KNHANES). Insulin resistance was defined as the homeostatic model assessment of insulin resistance (HOMA-IR) values greater than the 80th percentile.

RESULTS

The mean values of most cardiometabolic variables increased proportionally with TG/HDL-C quartiles. Compared to individuals in the lowest TG/HDL-C quartile, the odds ratio for insulin resistance for individuals in the highest quartile was 2.91 in boys and 2.38 in girls after adjusting for confounding variables.

CONCLUSIONS

This study suggests that TG/HDL-C could be a convenient marker for identifying Korean adolescents with insulin resistance.

Waist-to-height ratio as a marker of low-grade inflammation in obese children and adolescents

BACKGROUND

The epidemic of childhood obesity is associated with early atherosclerosis. Several reports have related this event to low-grade inflammation described in obesity. CRP and IL6 are markers that correlate with adiposity. The waist-to-height ratio (WtHR) is an anthropometric marker associated with insulin resistance and inflammation. The objective of this study was to assess the correlation between WtHR, metabolic complications and pro-inflammatory factors in obese children and adolescents.

METHODS

Weight, height, waist circumference, glycemia, insulin, CRP, TNF-α and IL-6 were measured in the baseline sample in 280 patients 6-19 years of age with overweight or obesity (OW/OB) and 112 normal-weight controls. Logistic regression was performed using WtHR as an independent variable. p>0.05 STATA11.

RESULTS

Mean WtHR was 0.6±0.06 in OW/OB and 0.43±0.02 in controls (p<0.01). WtHR was increased in 93% of the OW/OB vs. 2% of the controls. In the OW/OB inflammatory markers were significantly increased (p<0.01) compared to the controls (CRP 2.2 vs. 0.8; Il-6 2.9 vs. 2.1; and TNF-α 6.2 vs. 5.5). In the WtHR>0.5, insulin resistence and inflammatory markers were significantly increased (p<0.01) compared to the WtHR<0.5 (HOMA 3.4 vs. 1.4; CRP 2.3 vs. 0.6; Il-6 2.9 vs. 2.1; and TNF-α 6.4 vs. 5.55). In logistic regression, a significant independent association was found between WtHR with CRP (OR1.47), IL6 (OR1.60) and TNF-α (OR1.79).

CONCLUSIONS

Obese children and adolescents have high inflammatory markers that may increase cardiovascular risk. WtHR is associated with low-grade inflammation and may be considered a relevant anthropometric marker in the clinical practice.

Metabolic endotoxaemia in childhood obesity

Background

Childhood obesity is associated with chronic low-grade inflammation considered as a precursor to metabolic disease; however, the underlying mechanisms for this remain unclear. Studies in adults have implicated gut derived gram-negative bacterial fragments known as lipopolysaccharide or endotoxin, activating the inflammatory response, whilst the importance in childhood obesity is unclear. The aim of this research is to understand the relationship between circulating endotoxin in childhood obesity, and its’ association with inflammatory and cardiovascular (CV) injury biomarkers.

Methods

Fasted blood was obtained from children with varying degrees of obesity (age: 13.9 ± 2.3Yr; BMI: 35.1 ± 5.2 Kg/m²; n = 60). Multiplex CVD biomarker immunoassays were used to determine systemic levels of inflammatory and vascular injury biomarkers, such as tumour necrosis factor-α (TNF-α), interleukin (IL-) 1β, 6, 8 and 10, plasminogen activator inhibitor-1 (PAI-1), soluble intercellular adhesion molecule type-1 (sICAM-1), matrix metalloproteinase-9 (MMP-9), myeloperoxidase (MPO) and vascular endothelial growth factor (VEGF) as well as endotoxin levels.

Results

Endotoxin levels demonstrated a significant and positive correlation with the markers for inflammation, vascular injury and atherogenesis (TNF-α: r² = 0.077, p < 0.05; PAI-1: r² = 0.215, p < 0.01; sICAM-1: r² = 0.159, p < 0.01; MMP-9: r² = 0.159, p < 0.01; MPO: r² = 0.07, p < 0.05; VEGF: r² = 0.161, p < 0.01). Males demonstrated significantly higher circulating endotoxin than females (Males: 9.63 ± 5.34 EU/ml; p = 0.004; Females: 5.56 ± 4.06 EU/ml; n = 60) in these BMI and age-matched cohorts.

Conclusion

The present study demonstrates for the first time a significant association between circulating endotoxin and biomarkers of metabolic risk in children as young as 11 years. Thus, endotoxin-mediated sub-clinical inflammation during childhood obesity may be a key contributor to T2DM and CVD development later in life.

Association of myeloperoxidase levels with cardiometabolic factors and renal function in prepubertal children

INTRODUCTION

Myeloperoxidase (MPO), an enzyme linking obesity and cardiovascular (CV) risk in adults, has rarely been studied in young children and no studies assessed its association with renal function. We sought to explore a possible association between serum MPO levels, obesity, CV risk factors and renal function in prepubertal children.

MATERIALS/METHODS

Cross-sectional evaluation of 309 children aged 8-9 years (161 normal weight, 148 overweight/obese), members of the birth cohort Generation I (Portugal). Anthropometrics (body mass index (BMI), waist-to-height ratio (WHtR) and % body fat mass (%BFM) by bioelectrical impedance analysis), 24-h ambulatory blood pressure monitoring and pulse wave velocity (PWV) were measured. Insulin resistance was estimated by the HOMA index (considering serum fasting glucose and insulin determinations). Serum MPO levels were assessed by immunoenzymatic assay.

RESULTS

MPO levels were positively associated with obesity indices (BMI z-score, WHtR and %BFM). Higher MPO levels were associated with higher 24-h and night-time mean arterial pressure, with nondipping and with higher values of insulin resistance. In normal weight children, the endothelial function, as evaluated indirectly by PWV, was an independent predictor of MPO levels. In overweight/obese children, estimated glomerular filtration rate increased significantly across tertiles of MPO (Ptrend = 0·031) and this association held after adjustment for age, sex, neutrophil and monocyte counts and CV risk factors.

CONCLUSIONS

Our results reinforce the role of MPO as a risk marker in obesity and related CV morbidities in young children. MPO levels associate with the dipping pattern and PWV and, among overweight/obese children, an association exists between MPO and renal function.

Metabolic Syndrome in Children and Adolescents: a Critical Approach Considering the Interaction between Pubertal Stage and Insulin Resistance

Pediatricians increasingly diagnose the metabolic syndrome (MetS) in recent years to describe cardiovascular risk and to guide management of the obese child. However, there is an ongoing discussion about how to define the MetS in childhood and adolescence. Since insulin resistance-the major driver of MetS-is influenced by pubertal stage, it is questionable to use definitions for MetS in children and adolescents that do not take into account pubertal status. A metabolic healthy status in prepubertal stage does not predict a metabolic healthy status during puberty. Furthermore, cardiovascular risk factors improve at the end of puberty without treatment. However, having a uniform internationally accepted definition of the MetS for children and adolescents would be very helpful for the description of populations in different studies. Therefore, the concept of MetS has to be revisited under the influence of puberty stage.

Associations among Inflammatory Biomarkers in the Circulating, Plasmatic, Salivary and Intraluminal Anatomical Compartments in Apparently Healthy Preschool Children from the Western Highlands of Guatemala

Background

Undernutrition and inflammation are related in many ways; for instance, non-hygienic environments are associated with both poor growth and immunostimulation in children.

Objective

To describe any existing interaction among different inflammation biomarkers measured in the distinct anatomical compartments of whole blood, feces, plasma and saliva.

Methods

In this descriptive, cross-sectional study, samples of whole blood, feces, plasma and saliva were collected on the 8^th and last week of observation among 87 attendees (42 girls and 45 boys) of 3 daycare centers offering a common 40-day rotating menu in Guatemala’s Western Highlands. Analyses included white blood cell count (WBC), fecal calprotectin, and plasmatic and salivary cytokines including IL-1B, IL-6, IL-8, IL-10 and TNF-α. Associations were assessed using Spearman rank-order and goodness-of-fit correlations, as indicated, followed by backwards-elimination multiple regression analyses to determine predictor variables for IL-10 in both anatomical compartments.

Results

Of a total of 66 cross-tabulations in the Spearman hemi-matrix, 22 (33%) were significantly associated. All 10 paired associations among the salivary cytokines had a significant r value, whereas 7 of 10 possible associations among plasma cytokines were significant. Associations across anatomical compartments, however, were rarely significant. IL-10 in both biological fluids were higher than corresponding reference values. When a multiple regression model was run in order to determine independent predictors for IL-10 in each anatomical compartment separately, IL-6, IL-8 and TNF-α emerged as predictors in plasma (r² = 0.514) and IL-1B, IL-8 and TNF-α remained as independent predictors in saliva (r² = 0.762). Significant cross-interactions were seen with WBC, but not with fecal calprotectin.

Conclusion

Interactions ranged from robust within the same anatomical compartment to limited to nil across distinct anatomical compartments. The prominence of the anti-inflammatory cytokine, IL-10, in both plasma and saliva is consistent with its counter-regulatory role facing a broad front of elevated pro-inflammatory cytokines in the same compartment.

Genome-wide expression in visceral adipose tissue from obese prepubertal children

Characterization of the genes expressed in adipose tissue (AT) is key to understanding the pathogenesis of obesity and to developing treatments for this condition. Our objective was to compare the gene expression in visceral AT (VAT) between obese and normal-weight prepubertal children. A total of fifteen obese and sixteen normal-weight children undergoing abdominal elective surgery were selected. RNA was extracted from VAT biopsies. Microarray experiments were independently performed for each sample (six obese and five normal-weight samples). Validation by quantitative PCR (qPCR) was performed on an additional 10 obese and 10 normal-weight VAT samples. Of 1276 differentially expressed genes (p < 0.05), 245 were more than two-fold higher in obese children than in normal-weight children. As validated by qPCR, expression was upregulated in genes involved in lipid and amino acid metabolism (CES1, NPRR3 and BHMT2), oxidative stress and extracellular matrix regulation (TNMD and NQO1), adipogenesis (CRYAB and AFF1) and inflammation (ANXA1); by contrast, only CALCRL gene expression was confirmed to be downregulated. In conclusion, this study in prepubertal children demonstrates the up- and down-regulation of genes that encode molecules that were previously proposed to influence the pathogenesis of adulthood obesity, as well as previously unreported dysregulated genes that may be candidate genes in the aetiology of obesity.