Preatherosclerosis and adiponectin subfractions in obese adolescents

Distribution of subcutaneous and intermuscular fatty tissue of the mid-thigh measured by MRI-A putative indicator of serum adiponectin level and individual factors of cardio-metabolic risk

Obesity and metabolic syndrome (MetS) are associated with hypoadiponectinemia. On the contrary, studies revealed correlations between the amount of subcutaneous adipose tissue (SAT) and higher serum adiponectin levels. Furthermore, independent association of intermuscular adipose tissue (IMAT) deposit in the thigh with cardiometabolic risk factors (including total blood cholesterol, low-density lipoprotein (LDL), and triglycerides), and decreased insulin sensitivity, as MetS components, are sufficiently described. The combined relationship of thigh IMAT and SAT with serum adiponectin, leptin levels, and cardiometabolic risk factors have not been investigated till date. Since both SAT and IMAT play a role in fat metabolism, we hypothesized that the distribution pattern of SAT and IMAT in the mid-thigh might be related to adiponectin, leptin levels, and serum lipid parameters. We performed adipose tissue quantification using magnetic resonance imaging (MRI) of the mid-thigh in 156 healthy volunteers (78 male/78 female). Laboratory measurements of lipid panel, serum adiponectin, and leptin levels were conducted. Total serum adiponectin level showed a significant correlation with the percentage of SAT of the total thigh adipose tissue (SAT/ (IMAT+SAT)) for the whole study population and in sex-specific analysis. Additionally, SAT/(IMAT+SAT) was negatively correlated with known cardiometabolic risk factors such as elevated total blood cholesterol, LDL, and triglycerides; but positively correlated with serum high-density lipoprotein. In multiple linear regression analysis, (SAT/(IMAT+SAT)) was the most strongly associated variable with adiponectin. Interestingly, leptin levels did not show a significant correlation with this ratio. Adipose tissue distribution in the mid-thigh is not only associated to serum adiponectin levels, independent of sex. This proposed quantitative parameter for adipose tissue distribution could be an indicator for individual factors of a person`s cardiometabolic risk and serve as additional non-invasive imaging marker to ensure the success of lifestyle interventions.

T-Cadherin and the Ratio of Its Ligands as Predictors of Carotid Atherosclerosis: A Pilot Study

In the cardiovascular system, atherogenic low-density lipoproteins (LDL) and the protective hormone adiponectin bind to the same receptor, T-cadherin. In this study, we tested the hypothesis that the ratio of circulating LDL to high-molecular weight (HMW) adiponectin could predict the development of atherosclerosis. Using enzyme-linked immunosorbent assay, we measured the level of circulating HMW adiponectin in the blood of donors together with ultrasound measuring of intima-media thickness (IMT) of carotid arteries. Single-nucleotide polymorphisms in the T-cadherin gene were identified using polymerase chain reaction. We found that carotid artery IMT is inversely correlated with the level of HMW in male subjects. We also found that the G allele of rs12444338 SNP in the T-cadherin gene correlates with a lower level of circulating T-cadherin and thinner IMT and therefore could be considered as an atheroprotective genotype. Despite our data, we could not provide direct evidence for the initial study hypothesis. However, we did uncover an important correlation between circulating T-cadherin and thinner carotid IMT.

Adiponectin signalling in bone homeostasis, with age and in disease

Adiponectin is the most abundant circulating adipokine and is primarily involved in glucose metabolism and insulin resistance. Within the bone, osteoblasts and osteoclasts express the adiponectin receptors, however, there are conflicting reports on the effects of adiponectin on bone formation and turnover. Many studies have shown a pro-osteogenic role for adiponectin in in vivo murine models and in vitro: with increased osteoblast differentiation and activity, alongside lower levels of osteoclastogenesis. However, human studies often demonstrate an inverse relationship between adiponectin concentration and bone activity. Moreover, the presence of multiple isoforms of adiponectin and multiple receptor subtypes has the potential to lead to more complex signalling and functional consequences. As such, we still do not fully understand the importance of the adiponectin signalling pathway in regulating bone homeostasis and repair in health, with age and in disease. In this review, we explore our current understanding of adiponectin bioactivity in the bone; the significance of its different isoforms; and how adiponectin biology is altered in disease. Ultimately, furthering our understanding of adiponectin regulation of bone biology is key to developing pharmacological and non-pharmacological (lifestyle) interventions that target adiponectin signalling to boost bone growth and repair in healthy ageing, following injury or in disease.

Adiponectin Is Related to Cardiovascular Risk in Severe Mental Illness Independent of Antipsychotic Treatment

Background: Schizophrenia (SCZ) and bipolar disorder (BD) are severe mental illnesses (SMI) associated with elevated cardiovascular disease (CVD) risk, including obesity. Leptin and adiponectin are secreted by adipose tissue, with pro- and anti-inflammatory properties, respectively. The second generation antipsychotics (AP) olanzapine, clozapine, and quetiapine have been associated with high leptin levels in SMI. However, the link between inflammatory dysregulation of leptin and adiponectin and CVD risk in SMI, and how this risk is influenced by body mass and AP medication, is still not completely understood. We investigated herein if leptin, adiponectin or their ratio (L/A ratio) could predict increased CVD risk in SCZ, BD, and in subgroups according to use of antipsychotic (AP) treatment, independent of other cardio-metabolic risk factors. Methods: We measured fasting plasma levels of leptin and adiponectin, and calculated the L/A ratio in n = 1,092 patients with SCZ and BD, in subgroups according to AP treatment, and in n = 176 healthy controls (HC). Differences in the levels of adipokines and L/A between groups were examined in multivariate analysis of covariance, and the correlations between adipokines and body mass index (BMI) with linear regression. CVD risk was defined by total cholesterol/high-density lipoprotein (TC/HDL) and triglyceride/HDL (TG/HDL) ratios. The adipokines and L/A ratios ability to discriminate individuals with TG/HDL and TC/HDL ratios above threshold levels was explored by ROC analysis, and we investigated the possible influence of other cardio-metabolic risk factors on the association in logistic regression analyses. Results: We observed higher leptin levels and L/A ratios in SMI compared with HC but found no differences in adiponectin. Both adipokines were highly correlated with BMI. The low adiponectin levels showed a fair discrimination in ROC analysis of individuals with CVD risk, with AUC between 0.7 and 0.8 for both TC/HDL and TG/HDL, in all groups examined regardless of diagnosis or AP treatment. Adiponectin remained significantly associated with an elevated TC/HDL and TG/HDL ratio in SMI, also after further adjustment with other cardio-metabolic risk factors. Conclusions: Adiponectin is not dysregulated in SMI but is associated with CVD risk regardless of AP treatment regime.

Immune-Mediated Inflammation in Vulnerable Atherosclerotic Plaques

Atherosclerosis is a chronic long-lasting vascular disease leading to myocardial infarction and stroke. Vulnerable atherosclerotic (AS) plaques are responsible for these life-threatening clinical endpoints. To more successfully work against atherosclerosis, improvements in early diagnosis and treatment of AS plaque lesions are required. Vulnerable AS plaques are frequently undetectable by conventional imaging because they are non-stenotic. Although blood biomarkers like lipids, C-reactive protein, interleukin-6, troponins, and natriuretic peptides are in pathological ranges, these markers are insufficient in detecting the critical perpetuation of AS anteceding endpoints. Thus, chances to treat the patient in a preventive way are wasted. It is now time to solve this dilemma because clear results indicate a benefit of anti-inflammatory therapy per se without modification of blood lipids (CANTOS Trial, NCT01327846). This fact identifies modulation of immune-mediated inflammation as a new promising point of action for the eradication of fatal atherosclerotic endpoints.

Weight Gain During Treatment of Bipolar Disorder (BD)-Facts and Therapeutic Options

Bipolar disorder (BPD) is a mood disorder, which is characterized by alternating affective states, namely (hypo)mania, depression, and euthymia. Evidence is growing that BPD has indeed a biologic substrate characterized by chronic inflammation, oxidative stress, and disturbed energy metabolism. Apart from this, there is obviously a hereditary component of this disease with multi-genetic factors. Most probably a susceptibility threshold favors the outbreak of clinical disease after a cascade of stress events that remain to be elucidated in more detail. Evidence is also growing that weak points in brain energy metabolism contribute to outbreak and severity of BPD. Conventional psychopharmacologic therapy must be reassessed under the aspects of weight cycling and development of central obesity as a deterioration factor for a worse clinical course leading to early cardiovascular events in BPD subgroups.

Fibroblast Growth Factor 21, Adiponectin, and Irisin as Markers of Unfavorable Metabolic Features in 12-Year-Old Children

CONTEXT

Among cytokines, fibroblast growth factor 21 (FGF21), adiponectin (Adn), and irisin have been considered potential biomarkers for insulin sensitivity (IS).

OBJECTIVE

We evaluated whether serum FGF21, Adn, and irisin associate with markers of IS and serum lipids in 12-year-old children.

DESIGN PARTICIPANTS AND MAIN OUTCOME MEASURES

This cohort study included 192 12-year-old children (109 girls). Seventy-eight of them had been born appropriate for gestational age (AGA), 70 small for gestational age (SGA), and 44 from preeclamptic pregnancies (PREs) as AGA. Fasting serum FGF21, Adn, irisin, lipids, inflammatory markers, and IS markers were measured. Quantitative insulin sensitivity check index (QUICKI) was calculated.

RESULTS

The means of serum FGF21, high molecular weight (HMW) Adn, and irisin did not differ between the sexes or between the SGA, AGA, and PRE children. In the whole study population, FGF21 associated positively with irisin and uric acid and negatively with leptin and high-density lipoprotein cholesterol (HDL-C). HMW Adn associated positively with total Adn, HDL-C, leptin, and SHBG. Apart from FGF21, irisin associated positively with insulin, high-sensitivity C-reactive protein, γ-glutamyltransferase, and triglycerides, and negatively with QUICKI, SHBG, and IGF binding protein-1. In multivariate regression analyses, irisin predicted lower IS and HMW Adn predicted higher HDL-C body mass index-independently, whereas FGF21 had no independent contribution to IS or lipid variables.

CONCLUSION

In 12-year-old children, serum irisin was associated with markers reflecting reduced IS. HMW Adn predicted HDL-C, whereas FGF21 did not contribute to IS or lipid parameters in multivariate regression analyses.

Higher adiponectin concentrations are associated with reduced metabolic syndrome risk independently of weight status in Brazilian adolescents

OBJECTIVE

To evaluate the association between adiponectin concentrations and metabolic syndrome (MetS) risk and to investigate if this association is independent of weight status in adolescents.

METHODS

Adiponectin concentrations and MetS risk were assessed in 4546 Brazilian adolescents (12-17 years old) enrolled in The Study of Cardiovascular Risks in Adolescents ("ERICA"), a cross-sectional multicenter study in Brazil. For analyses, adiponectin was categorized in sex and age-specific quartiles and MetS risk was expressed as a continuous score, calculated as the average of the standardized values (z-score) of the five MetS components. Multiple linear regression models were used to investigate the association between the quartiles of adiponectin and MetS risk.

RESULTS

Adiponectin was inversely associated with waist circumference and log-transformed triglycerides, and positively associated with HDL-c. We also observed an inverse association between adiponectin concentrations and MetS risk. After adjustment for sociodemographic variables, physical activity, skipping breakfast and body mass index (BMI), higher quartiles of adiponectin remained inversely associated with waist circumference and MetS risk. A direct association between adiponectin and HDL-c was also observed. In further analysis, the sample was stratified by weight status and an inverse association between quartiles of adiponectin and MetS risk was observed in both normal weight and overweight/obese adolescents.

CONCLUSION

Higher adiponectin concentrations were independently and inverse associated with MetS risk in Brazilian adolescents, even after adjusting for BMI. These results were similar in normal weight and overweight/obese adolescents, suggesting that adiponectin may play a role in early development of MetS.

Abnormality of adipokines and endothelial dysfunction in Mexican obese adolescents with insulin resistance

PURPOSE

The aim of this study was to investigate the possible relationship among insulin resistance (IR), endothelial dysfunction, and alteration of adipokines in Mexican obese adolescents and their association with metabolic syndrome (MetS).

MATERIALS AND METHODS

Two hundred and twenty-seven adolescents were classified according to the body mass index (BMI) (control: N=104; obese: N=123) and homeostasis model of the assessment-insulin resistance index (HOMA-IR) (obese with IR: N=65). The circulating concentrations of leptin, adiponectin, soluble intercellular adhesion molecule-1 (sICAM-1), and IR were determined by standard methods.

RESULTS

The obese adolescents with IR presented increased presence of MetS and higher circulating concentrations in sICAM-1 in comparison with the obese subjects without IR. The lowest concentrations of adiponectin were observed in the obese with IR. In multivariate linear regression models, sICAM-1 along with triglycerides, total cholesterol, and waist circumference was strongly associated with HOMA-IR (R²=0.457, P=0.008). Similarly, after adjustment for age, BMI-SDS, lipids, and adipokines, HOMA-IR remained associated with sICAM-1 (R²=0.372, P=0.008). BMI-SDS was mildly associated with leptin (R²=0.176, P=0.002) and the waist circumference was mild and independent determinant of adiponectin (R²=0.136, P=0.007).

CONCLUSIONS

Our findings demonstrated that the obese adolescents, particularly the obese subjects with IR exhibited increased presence of MetS, abnormality of adipokines, and endothelial dysfunction. The significant interaction between IR and endothelial dysfunction may suggest a novel therapeutic approach to prevent or delay systemic IR and the genesis of cardiovascular diseases in obese patients.

Fetuin-A, adiposity-linked insulin resistance and responsiveness to an educational-based weight excess reduction program: a population-based survey in prepubertal schoolchildren

The secreted hepatokine fetuin-A emerges as an independent predictor of type 2 diabetes in adulthood. The overall aims of this study were: (1) to investigate the associations of fetuin-A with adiposity and insulin resistance, as well as its relationship with adipokines, in prepubertal children, and, (2) to evaluate whether, in prepubertal obesity, serum fetuin-A levels may either change or predict the responsiveness to an educational-based weight excess reduction program. We studied 200 prepubertal children (boys/girls: 89/111; Tanner stage 1; age: 5-13 years), included in a cohort of 44,231 adolescents who participated in an extensive Italian school-based survey. According to Cole's criteria, 100 individuals were lean (boys/girls: 57/43) and 100 obese (boys/girls: 54/46). A subset of 53 obese individuals (boys/girls: 28/25; age: 6-12 years) were also evaluated after a weight excess reduction program. Serum fetuin-A, leptin, total and high molecular weight adiponectin levels, as well as homeostasis model assessment of insulin resistance were assessed. When compared with lean, obese children exhibited higher ( p < 0.0001) fetuin-A concentrations, without differences between sex. Fetuin-A was positively associated with adiposity, homeostasis model assessment of insulin resistance, and leptin levels. In multivariate analysis, the associations between fetuin-A and leptin or homeostasis model assessment of insulin resistance lost the significance after adjustment for BMI _Z-score, which, in turn, represented an independent determinant of fetuin-A (R ²_adj 0.327; p < 0.0001). Notably, after weight excess reduction program, fetuin-A levels dropped ( p < 0.0001 vs. basal). Interestingly, no significant differences of fetuin-A concentrations between responders and no responders were found. In prepubertal children, fetuin-A represents an early marker of adiposity, and its reduction after lifestyle intervention may partly contribute to the beneficial effects of weight excess reduction program.

Influence of Antioxidants on Leptin Metabolism and its Role in the Pathogenesis of Obesity

Obesity is associated with low-grade inflammation. Leptin, a hormone made by fat cells regulates appetite and hunger and thus food intake behavior. Interestingly, , food preservatives like sodium sulfite and sodium benzoate and also natural colorant and spice compounds such as curcumin were found to decrease the release of leptin in murine 3T3-L1 adipocytes, after co-incubation with LPS, which was added to mimic the pro-inflammatory status in obesity. Several of these compounds are well known food antioxidants.Whilst reducing oxidation events is beneficial in states of elevated oxidative stress, overexposure to food antioxidant can lead to adverse effects. There are hints from in vivo data, that antioxidant stress in younger age plays a role in the development of adiposity in later life. The insufficient exposure to oxidizing compounds like reactive oxygen species (ROS) cannot only cause an insufficient burning of calories but there is also a link to the regulation of food intake behavior. If the in vitro findings can be extrapolated to the in vivo situation, consumption of antioxidant supplemented food could lead to decreased leptin release and contribute to an obesogenic environment. This aspect sheds some new critical light on the potential role of an antioxidant-enriched nutrition in the obesity epidemic during the past few centuries. Doing sports could represent not only a proper strategy to initiate physiological ROS production and burning of calories, but also may shift the hormone milieu towards a reduction of hunger feelings and thus reduce appetite and food intake.

Endothelial and Metabolic Function Interactions in Overweight/Obese Children

AIM

Although the underlined mechanisms are still unknown, metabolic/coagulation alterations related to childhood obesity can induce vascular impairments. The aim of this study was to investigate the relationship between metabolic/coagulation parameters and endothelial function/vascular morphology in overweight/obese children.

METHODS

Thirty-five obese/overweight children (22 pre-pubertal, mean age: 9.52±3.35 years) were enrolled. Body mass index (BMI), homeostasis model assessment index (HOMAIR), metabolic and coagulation parameters, [adiponectin, fibrinogen, high molecular weight adiponectin (HMW), endothelin-1, and vonWillebrand factor antigen] ultrasound early markers of atherosclerosis [flow-mediated dilatation (FMD), common carotid intima-media thickness (C-IMT), and anteroposterior diameter of infra-renal abdominal aorta (APAO)] were assessed.

RESULTS

APAO was related to anthropometric (age: r=0.520, p=0.001; height: r=0.679, p＜0.001; weight: r=0.548, p=0.001; BMI: r=0.607, p＜0.001; SBP: r=0.377, p=0.026) and metabolic (HOMAIR: r=0.357, p=0.035; HMW: r=－0.355, p=0.036) parameters. Age, height, and systolic blood pressure were positively related to increased C-IMT (r=0.352, p=0.038; r=0.356, p=0.036; r=0.346, p=0.042, respectively). FMD was not related to any clinical and biochemical characteristics of the pediatric population. Age, HOMAIR, fasting glucose levels, and HMW were independent predictors for APAO increase. Each unit decrease in HMW concentrations (1 μg/ml) induced a 0.065 mm increase in APAO.

CONCLUSION

High molecular weight adiponectin is related to cardiovascular risk in overweight/obese children.

Adiposity trajectory and its associations with plasma adipokine levels in children and adolescents-A prospective cohort study

OBJECTIVE

This study aimed to examine the associations of longitudinal adiposity measures with two adipokines, leptin and adiponectin, and their ratio in children and adolescents.

METHODS

A total of 953 children and adolescents participated in a 6-year longitudinal study. Body mass index (BMI), percentage body fat (%BF), and fat mass index (FMI) were used to assess adiposity status.

RESULTS

After adjusting for possible confounders, our regression models revealed that BMI, %BF, and FMI, in both the baseline and follow-up surveys were independently associated with a higher level of leptin and the leptin/adiponectin ratio at the follow-up survey, whereas the significant association with adiponectin only partly existed in adiposity measures at the follow-up visit. Moreover, the longitudinal change in adiposity measures was found to be a significant predictor for follow-up plasma adipokine levels. Compared with the low→low group, the medium→medium group, up-trend group, and high→high group all showed a significantly increased level of leptin and leptin/adiponectin ratio. The up-trend group and high→high group also had significantly decreased adiponectin levels.

CONCLUSIONS

These findings highlight the importance of adiposity surveillance and the utility of adipokines as biomarkers for adverse metabolic consequences of childhood adiposity.

Association of Adiponectin with Adolescent Cardiovascular Health in a Dietary Intervention Study

OBJECTIVE

To investigate whether an infancy-onset, low saturated fat-oriented dietary intervention influences serum adiponectin concentration in adolescents, and to study the association of adiponectin with subclinical markers of vascular health, and cardio-metabolic risk factors.

STUDY DESIGN

The longitudinal, randomized Special Turku Coronary Risk Factor Intervention Project aimed to modify child's dietary fat quality replacing saturated fat with unsaturated fat. Serum adiponectin (n = 521) along with weight, height, high-density lipoprotein cholesterol, C-reactive protein (CRP), triglycerides, and insulin were measured at age 15 years. Adiposity was assessed using body mass index, waist circumference, and abdominal fat thickness measured with ultrasound. Metabolic syndrome was defined according to International Diabetes Foundation criteria. Vascular ultrasound measures including carotid intima-media thickness (IMT) were assessed.

RESULTS

Adiponectin concentrations were similar in the intervention and control groups (P = .16). Adiponectin associated with carotid IMT (r = -0.13, P = .005), high-density lipoprotein cholesterol (r = 0.18, P < .0001), triglycerides (r = -0.16, P = .0004), CRP (r = -0.10, P = .02), insulin (r = -0.14, P = .002), and adiposity (r = -0.18-0.24, P ≤ .0001). When adjusted for adiposity indices, the association with carotid IMT was only marginally diluted (P = .03-.06), but the associations with insulin and CRP became nonsignificant. Adolescents with adiponectin ≤median had 4-fold risk of metabolic syndrome than peers with adiponectin >median (CI 1.8-10.2, P = .0001).

CONCLUSIONS

In healthy adolescents, low serum adiponectin is related with carotid IMT and metabolic syndrome. We found no evidence that repeated low saturated fat-oriented dietary counseling would influence serum adiponectin in adolescence.

TRIAL REGISTRATION

Registered with ClinicalTrials.gov: NCT00223600.

Cardiovascular complications of type 2 diabetes in youth

The prevalence of type 2 diabetes mellitus (T2DM) in youth has increased dramatically over the past decades. The literature also suggests that the progression from an impaired glucose tolerance state to established T2DM is more rapid in youth, compared to adults. The presence of significant cardiovascular complications in youth with T2DM, including cardiac, macrovascular, and microvascular remodeling, is another major issue in this younger cohort and poses a significant threat to the healthcare system. However, this issue is only now emerging as a major public health concern, with few data to support optimal treatment targets and strategies to reduce cardiovascular disease (CVD) risk in youth with T2DM. Accordingly, the purpose of this minireview is to better understand the cardiovascular complications in youth with T2DM. We briefly describe the pathophysiology from youth studies, including oxidative stress, inflammation, renin-angiotensin aldosterone system, and epigenetics, which link T2DM and CVD. We also describe the literature concerning the early signs of CVD in youth and potential treatment options to reduce cardiovascular risk.

Interleukin 10-coated nanoparticle systems compared for molecular imaging of atherosclerotic lesions

Atherosclerosis (AS) is one of the leading causes of mortality in high-income countries. Early diagnosis of vulnerable atherosclerotic lesions is one of the biggest challenges currently facing cardiovascular medicine. The present study focuses on developing targeted nanoparticles (NPs) in order to improve the detection of vulnerable atherosclerotic-plaques. Various biomarkers involved in the pathogenesis of atherosclerotic-plaques have been identified and one of these promising candidates for diagnostic targeting is interleukin 10 (IL10). IL10 has been shown to be a key anti-inflammatory responding cytokine in the early stages of atherogenesis, and has already been used for therapeutic interventions in humans and mice. IL10, the targeting sequence, was coupled to two different types of NPs: protamine-oligonucleotide NPs (proticles) and sterically stabilized liposomes in order to address the question of whether the recognition and detection of atherosclerotic-lesions is primarily determined by the targeting sequence itself, or whether it depends on the NP carrier system to which the biomarker is coupled. Each IL10-targeted NP was assessed based on its sensitivity and selectivity toward characterizing atherosclerotic-plaque lesions using an apolipoprotein E-deficient mouse as the model of atherosclerosis. Aortas from apolipoprotein E-deficient mice fed a high fat diet, were stained with either fluorescence-labeled IL10 or IL10-coupled NPs. Ex vivo imaging was performed using confocal laser-scanning microscopy. We found that IL10-targeted proticles generated a stronger signal by accumulating at the surface of atherosclerotic-plaques, while IL10-targeted, sterically stabilized liposomes showed a staining pattern deeper in the plaque compared to the fluorescence-labeled IL10 alone. Our results point to a promising route for enhanced in vivo imaging using IL10-targeted NPs. NPs allow a higher payload of signal emitting molecules to be delivered to the atherosclerotic-plaques, thus improving signal detection. Importantly, this allows for the opportunity to visualize different areas within the plaque scenario, depending on the nature of the applied nanocarrier.

Normal weight estonian prepubertal boys show a more cardiovascular-risk-associated adipose tissue distribution than austrian counterparts

Objective. Risk phenotypes for cardiovascular disease (CVD) differ markedly between countries, like the reported high difference in CVD mortality in Austria and Estonia. Hitherto, the goal of this study was to find out risk profiles in body fat distribution yet present in childhood, paving the way for later clinical end points. Methods. he subcutaneous adipose tissue (SAT) distribution patterns in 553 Austrian (A) and Estonian (E) clinically healthy normal weight boys aged 11.1 (±0.8) years were analysed. We applied the patented optical device Lipometer which determines the individual subcutaneous adipose tissue topography (SAT-Top). Results. Total body fat did not differ significantly between E and A boys. A discriminant analysis using all Lipometer data, BMI, and the total body fat (TBF) yielded 84.6% of the boys correctly classified in Estonians and Austrians by 9 body sites. A factor analysis identified the SAT distribution of E as critically similar to male adult patients with coronary heart disease (CHD). Conclusions. We show in normal weight Estonian boys a highly significant decreased fat accumulation on the lower body site compared to age matched Austrian males. This SAT-Top phenotype may play an important role for the increased cardiovascular risk seen in the Estonian population.

Atherosclerosis subclinical and inflammatory markers in obese and nonobese children and adolescents

We conducted a systematic review of intima-media thickness(IMT) and inflammatory markers, compared IMT and identified by meta-analysis related to EMI and inflammatory variables in obese and non-obese children and adolescents. We searched for articles in databases Pubmed, Bireme and Science Direct, during years 2000 to 2010, with the following key words in English: "obesity", "adolescents", "atherosclerosis" and "child ", They were used in two combinations: obesity + adolescents + atherosclerosis + child + obesity and atherosclerosis. We used meta-analysis to compare IMT between obese and non-obese patients. We carefully selected 16 articles for final analysis. There were differences in the thickness of IMT between obese and non-obese patients in 12 studies, confirmed by meta-analysis. Obese patients had concentrations of C-reactive protein higher in 13 articles analyzed (p < 0.05) and lower adiponectin levels in 4 (p < 0.05). In general, obese men had lower concentrations of adiponectin and higher values of IMT and C-reactive protein than non-obese men, showing the relationship between obesity and early inflammatory process. We concluded that there is a relationship of obesity with increased IMT and changes in concentrations of inflammatory markers in this phase.

Effects of a novel school-based cross-curricular physical activity intervention on cardiovascular disease risk factors in 11- to 14-year-olds: the activity knowledge circuit

PURPOSE

This study investigates cardiovascular disease risk factor response in adolescents following introduction of brisk walking into curriculum lessons.

DESIGN

Quasi-experimental.

SETTING

School-based.

SUBJECTS

An intervention group consisted of 115 (aged 12.4 ± 0.5 y) year eight participants, and 77 (aged 12.1 ± 1.1 y) year seven and year nine participants formed a control.

INTERVENTION

An 18-week cross-curricular physical activity intervention was implemented in one secondary school.

MEASURES

Adiposity variables, blood pressure, lipids, lipoproteins, glucose, insulin, high-sensitivity C-reactive protein, high-molecular-weight adiponectin, aerobic fitness, physical activity behavior, and diet were assessed preintervention and postintervention.

ANALYSIS

Dependent and independent t-tests.

RESULTS

Prevalence of elevated waist circumference (9.8% vs. 6.9%), systolic blood pressure (3.3% vs. 0%), triglycerides (2.5% vs. 1.2%), and reduced high density lipoprotein cholesterol (3.7% vs. 2.7%) decreased in the intervention group. Significant improvements in high density lipoprotein cholesterol to total cholesterol ratio (mean ± SD: 2% ± 4% [confidence interval (CI)(0.05)  =  1% to 2%], t(80)  =  -3.5, p  =  .001) and glucose (-.1 ± .4 mmol/L [CI(0.05)  =  -.2% to 0%], t(79)  =  3.2, p  =  .002) were evident for the intervention group.

CONCLUSION

The Activity Knowledge Circuit may prove to be a sustainable, effective, and cost-effective strategy to engage schoolchildren in physical activity on a daily basis. A longer-duration intervention is required to fully understand risk factor response in adolescents.

Adiponectin multimers, body weight and markers of cardiovascular risk in adolescence: Northern Ireland Young Hearts Project

BACKGROUND

Research examining the relationship between adiponectin (AN) isoforms, body weight and cardiovascular (CV) risk factors is limited, particularly in younger populations.

OBJECTIVES

To investigate the inter-relationships between AN isoforms and CV risk factors, and their dependence on body weight status, in adolescents.

DESIGN

Blood samples from 92 obese, 92 overweight and 92 normal weight age- and sex-matched adolescents were analysed for traditional cardiovascular disease (CVD) risk biomarkers and also total, high molecular weight (HMW), medium and low molecular weight (LMW) AN.

RESULTS

A significant inverse association was observed between total and HMW AN and waist-hip ratio (P=0.015, P=0.006, respectively), triglycerides (P=0.003, P=0.003, respectively) and systolic blood pressure (P=0.012, P=0.024, respectively) and a significant positive association with high-density lipoprotein (P<0.001, P<0.001, respectively) in multi-adjusted analyses. There was no evidence of a relationship between multimeric AN and high-sensitivity C-reactive protein. There was also little evidence of a relationship between LMW AN and CVD risk factors. There was a strong, body mass index (BMI)-independent, association between AN, CVD biomarkers and the hypertriglyceridemic waist phenotype.

CONCLUSION

Prominent, BMI-independent associations between total and HMW AN, but not LMW AN, and CVD risk factors were already evident in this young population. This research in adolescents supports the contention that AN subfractions may have different biological actions. These associations in apparently healthy adolescents suggest an important role for AN and its subfractions in the pathogenesis of metabolic syndrome traits and indicate that the potential for total or HMW AN to act as early universal biomarkers of CV risk warrants further study.

Measurement of waist circumference predicts coronary atherosclerosis beyond plasma adipokines

OBJECTIVE

The association of plasma adipokines beyond waist circumference (WC) with coronary artery calcification (CAC), a measure of subclinical atherosclerosis, is unknown.

DESIGN AND METHODS

Asymptomatic Caucasian individuals from two community-based cross-sectional studies (n = 1,285) were examined and multivariate analysis of traditional risk factors was performed, then WC and adipokines (adiponectin and leptin) were added. Incremental value of each was tested with likelihood ratio testing.

RESULTS

Beyond traditional risk factors, WC (Tobit regression ratio 1.69, P < 0.001) and plasma leptin (1.57, P < 0.001) but not plasma adiponectin (P = 0.75) were independently associated with CAC. In nested models, neither adiponectin (χ(2) = 0.76, P = 0.38) nor leptin (χ(2) = 1.32, P = 0.25) added value to WC beyond traditional risk factors, whereas WC added incremental value to adiponectin (χ(2) = 28.02, P < 0.0001) and leptin (χ(2) = 13.58, P = 0.0002).

CONCLUSION

In the face of important biomarkers such as plasma adiponectin and leptin, WC remained a significant predictor of CAC beyond traditional risk factors underscoring the importance of WC measurement during cardiovascular risk assessment.

Uric acid best predicts metabolically unhealthy obesity with increased cardiovascular risk in youth and adults

OBJECTIVE

The obesity prevalence is growing worldwide and largely responsible for cardiovascular disease, the most common cause of death in the western world. The rationale of this study was to distinguish metabolically healthy from unhealthy overweight/obese young and adult patients as compared to healthy normal weight age matched controls by an extensive anthropometric, laboratory, and sonographic vascular assessment.

DESIGN AND METHODS

Three hundred fifty five young [8 to < 18 years, 299 overweight/obese(ow/ob), 56 normal weight (nw)] and 354 adult [>18-60 years, 175 (ow/ob), 179 nw)] participants of the STYJOBS/EDECTA (STYrian Juvenile Obesity Study/Early DEteCTion of Atherosclerosis) cohort were analyzed. STYJOBS/EDECTA (NCT00482924) is a crossectional study to investigate metabolic/cardiovascular risk profiles in normal and ow/ob people free of disease except metabolic syndrome (MetS).

RESULTS

From 299 young ow/ob subjects (8-< 18 years), 108 (36%), and from 175 adult ow/ob subjects (>18-60 years), 79 (45%) had positive criteria for MetS. In both age groups, prevalence of MetS was greater among males. Overweight/obese subjects were divided into "healthy" (no MetS criterion except anthropometry fulfilled) and "unhealthy" (MetS positive). Although percentage body fat did not differ between "healthy" and "unhealthy" ow/ob, nuchal and visceral fat were significantly greater in the "unhealthy" group which had also significantly higher values of carotid intima media thickness (IMT). With MetS as the dependent variable, two logistic regressions including juveniles <18 years or adults >18 years were performed. The potential predictor variables selected with the exception of age and gender by t test comparisons included IMT, ultrasensitive c-reactive protein (US-CRP), IL-6, malondialdehyde (MDA), oxidized LDL, leptin, adiponectin, uric acid (UA), aldosterone, cortisol, transaminases, fibrinogen. In both groups, uric acid and in adults only, leptin and adiponectin, turned out as the best predictor.

CONCLUSION

Serum levels of UA are a significant predictor of unhealthy obesity in juveniles and adults.

Insulin resistance and inflammation markers: correlations in obese adolescents

AIMS AND OBJECTIVES

To ascertain whether inflammation markers also correlate with parameters related to insulin resistance and the metabolic syndrome in a group of adolescents.

BACKGROUND

Obesity is now considered a chronic low-grade inflammatory process, characterised by alterations in the systemic concentrations of some inflammation markers. Adiponectin, leptin and other inflammatory proteins have been shown to correlate with insulin resistance and the metabolic syndrome in adults.

DESIGN

Cross-sectional study in two groups of obese and normal weight adolescents.

METHODS

Serum levels of adiponectin, leptin, ceruloplasmin and insulin levels were determined and correlated among them and with anthropometric parameters, blood pressure body mass index and body mass index z-score.

RESULTS

Waist circumference, body mass index and blood pressure values correlated significantly with both homoeostasis model assessment for insulin resistance and insulin levels. Ceruloplasmin also correlated with both parameters with a high level of significance. However, leptin levels did not correlate with either homoeostasis model assessment for insulin resistance or insulin, and adiponectin correlated with homoeostasis model assessment for insulin resistance but not insulin. All inflammation markers studied correlated with the body mass index z-score. These correlations were stronger in the group of obese individuals compared to lean ones.

CONCLUSIONS

We found a relationship between insulin resistance and some inflammation in adolescents, which was particularly strong in obese individuals and was associated with the development of metabolic syndrome. Among the inflammation markers studied, ceruloplasmin revealed as a potential string marker of insulin resistance in obese adolescents.

RELEVANCE TO CLINICAL PRACTICE

The results obtained in this study imply a significant advance in the field of clinical practice of nursing. The adequate understanding by nursing personnel of the inflammatory processes inherent to obesity constitutes a key factor for the prevention of the disease and its complications in adolescents.

Serum resistin and inflammatory and endothelial activation markers in obese adolescents

OBJECTIVES

To assess the level of serum resistin in obese and lean children and to establish a relationship with circulating inflammatory and vascular markers.

STUDY DESIGN

This is a cross-sectional study including 67 obese and 62 lean children (mean age 10.9 ± 2.8 years, age range 5.4-16.6 years). We assessed circulating hormones (insulin, leptin, insulin-like growth factor 1), markers of inflammation (resistin, high sensitivity C-reactive protein, interleukin-6, chemokine ligand 2), and endothelial cell activation (vascular and intercellular adhesion molecules: vascular cell adhesion molecule 1 and intercellular adhesion molecule; E-selectin; P-selectin; endothelin 1).

RESULTS

Body weight, body mass index (BMI), insulin, leptin, high-sensitivity C-reactive protein, vascular adhesion molecule 1, and E-selectin levels were significantly higher in obese than in lean subjects. Resistin was similar among the groups in the prepubertal period, but increased significantly in the obese adolescents (18.6 ± 24.9) compared with lean subjects (7.9 ± 10.7 ng/mL; P = .038). Resistin was not associated with BMI z score (P > .05). Subjects with resistin levels above 9 (ng/mL) had higher concentration of interleukin-6, chemokine ligand 2, endothelin-1, and insulin-like growth factor 1 but not of leptin, insulin, or BMI.

CONCLUSION

Resistin was increased in obese adolescents independently of the quantity of the adipose tissue. In this population, increased resistin levels were related to inflammation and endothelial activation. We may hypothesize that interventions aiming to diminish resistin expression may slow down atherogenesis in adolescents.

Metabolic syndrome, mild cognitive impairment and Alzheimer's disease--the emerging role of systemic low-grade inflammation and adiposity

The past decade has shed new light on the etiology of Alzheimer's disease (AD), which is the consequence of interactions between numerous lesions. There is a growing body of evidence that the most beneficial effects of treatment might only be achieved in the preclinical stage of dementia, prior to the immense hallmarks of neurodegeneration. In view of this, several studies have focused on mild cognitive impairment (MCI) as a state, which represents a less severe form of the neuropathological process. However, early treatment interventions initiated in MCI have failed to slow down progression of the disease. Thus, great effort has been made to indicate modifiable risk factors for MCI. Consistent with the role of vascular malfunction in AD, this approach has shown the predictive value of the metabolic syndrome (MetS), which is a multidimensional entity and includes visceral obesity, dyslipidemia, hyperglycemia and hypertension. Despite the positive results of several epidemiological studies, the exact mechanisms underlying the connection between MetS and AD remain uncertain and various theories are being assessed. MetS, similarly to AD, has been attributed to a low-grade chronic inflammation. There is a general consensus that the aberrant inflammatory response underlying MetS may arise from a deregulation of the endocrine homeostasis of adipose tissue. Hence, it might be assumed that the subclinical inflammation of adipose tissue may interact with the impaired central inflammatory response, leading to neurodegeneration. This article reviews the role of low-grade inflammation of adipose tissue in the pathophysiology of cognitive impairment and translates several considerable and unexplored findings from studies focused on subjects with MetS and animal models mimicking the phenotype of MetS into the etiology of AD.

The association of carotid intima media thickness with retinol binding protein-4 and total and high molecular weight adiponectin in type 2 diabetic patients

BACKGROUND

The aim of this study was to investigate whether carotid intima media thickness (CIMT) is associated with serum level of retinol- binding protein-4 (RBP4) and total and high molecular weight (HMW) adiponectin in type 2 diabetes (T2DM) without clinical symptom of atherosclerotic disease.

METHOD

101 type 2 diabetic patients (mean age, 53.63 ± 8.42 years) and 42 body mass index (BMI) matched control (mean age 50.1 ± 8.4) were recruited. The CIMT was assessed by using B-mode ultrasonography, while serum levels of RBP4 and total and HMW adiponectin were measured by using enzyme linked immunosorbant assay (ELISA). Linear regression analysis was performed with CIMT as dependent variable and adipokines and cardio metabolic risk factors as independent variables.

RESULT

The CIMT was higher in diabetic group compared to control group (p <0.05). The mean concentration of RBP4 and total and HMW adiponectin did not differ between two groups.Age (B = 0.44 P <0.05), blood pressure (B = 0.37 P = <0.05), waist circumference (B = -0.21 P <0.05) and TG (B = 0.1 P <0.05) were identified as independent predictors for CIMT in diabetic group, while RBP4 and adiponectin were not associated with CIMT neither in diabetic group nor in control group.

CONCLUSION

In conclusion, the present study showed that serum levels of RBP4 or total and HMW adiponectin were not potential predictors of CIMT in type 2 diabetic patients who exposed to this risk factor at least for nine years.

Endothelial dysfunction, inflammation, and oxidative stress in obese children and adolescents: markers and effect of lifestyle intervention

With an increasing prevalence, pediatric obesity is often a prelude to adulthood obesity, and represents a major public health issue. Comorbidities are very common and severe in obese adults, justifying the search for earlier markers or risk factors for cardiovascular diseases in obese children. Endothelial dysfunction has been found to be present in the early stages of atherosclerosis, and can be non-invasively assessed with widely accepted and well-standardized techniques at the macrocirculation level. Endothelial dysfunction at the microcirculation level is less documented in obese children. Obesity in children has been repeatedly and independently correlated to endothelial dysfunction, inflammation and oxidative stress markers, although the relationship between these factors remains to be investigated. However, this would not only allow substantial improvements in risk stratification, but also provide essential data regarding the evolution of endothelial dysfunction in childhood obesity, especially during puberty when pro-inflammatory and pro-oxidative changes, with relative insulin resistance, occur. Therapeutic strategies such as lifestyle interventions in early childhood obesity appear all the more necessary, optimally including both exercise and diet because of their known effects on inflammatory and oxidative stress markers, potentially reversing endothelial dysfunction.

Physiological, pathological and potential therapeutic roles of adipokines

Formerly regarded purely as passive energy storage, adipose tissue is now recognized as a vital endocrine organ. Adipocytes secrete diverse peptide hormones named adipokines, which act in a autocrine, paracrine or endocrine way to influence several biological functions. Adipokines comprise diverse bioactive substances, including cytokines, growth, and complement factors, which perform essential regulatory functions related to energy balance, satiety and immunity. Presently adipokines have been widely implicated in obesity, diabetes, hypertension and cardiovascular diseases. In this article we aim to present a brief description of the roles and potential therapeutic modulation of adipokines, such as leptin, resistin, adiponectin, apelin, visfatin, FABP-4, tumor necrosis factor-α (TNF-α), interleukin-6 and plasminogen activator inhibitor-1 (PAI-1).

Associations of physical activity and fitness with adipocytokines in adolescents: the AFINOS Study

BACKGROUND AND AIMS

Adipocytokines may have a key role in the development of atherosclerosis and type 2 diabetes. The purpose of this study was to examine the independent and joint associations of physical activity (PA), cardiorespiratory fitness (CRF) and muscular fitness (MF) with adiponectin and leptin in adolescents.

METHODS AND RESULTS

A sample of 198 adolescents (96 girls), aged 13-17-year, was selected. Participants completed anthropometric measurements (height, weight, and waist circumference) and percentage of body fat (%BF) was estimated by bioelectrical impedance. PA was measured by accelerometer for 7-day. The 20-m shuttle-run test was used to assess CRF and two MF tests (handgrip strength and standing broad jump) were used to create an MF score. A cluster score of health status (0-3 risks) was created. Serum adiponectin and plasma leptin were also determined. Regression analyses controlling for age, sex, pubertal status and waist circumference showed that PA was not significantly associated with adiponectin and vigorous PA showed a significant inverse association with leptin. Both CRF and MF were significantly and inversely associated with adiponectin and leptin. Further analyses revealed that the 'healthy' group (0 risks) had significantly lower adiponectin and leptin than 'medium-healthy' (1 risk) and 'unhealthy' (2-3 risks) status groups.

CONCLUSIONS

PA, CRF and MF are inversely and jointly associated with adiponectin and leptin concentrations in adolescents.

Link between leptin and interleukin-6 levels in the initial phase of obesity related inflammation

The mechanisms underlying the pathogenesis of obesity-related atherosclerosis remain to be clarified. To investigate the preclinical phase, interleukin-6 (IL-6) plasma levels were analyzed together with clinical, anthropometric, inflammatory, and metabolic variables in a well-defined cohort of 677 young and middle-aged overweight/obese and normal-weight subjects. In the juvenile and adult overweight/obese study group, IL-6 levels were increased significantly compared with normal-weight, age-matched controls (P < 0.001). In both juveniles and adults, higher levels of IL-6 were observed in obese compared with overweight participants. Subjects with metabolic syndrome (MS) had significantly higher IL-6 levels than those without MS. In juveniles, leptin, and in adults, the waist-to-height ratio, turned out to be the best predictor of IL-6 plasma levels in a multiple stepwise regression model. Taken together, in every age group, interleukin-6 is associated positively with the grade of overweight. Interestingly, leptin, which is the best known adipokine, is associated predictively with interleukin-6 plasma levels only in juveniles, which may indicate an important role of this molecule in the initiation of obesity-related inflammation.

Globular domain of adiponectin: promising target molecule for detection of atherosclerotic lesions

BACKGROUND

Adiponectin, an adipocyte-specific plasma protein, has been shown to accumulate in injured endothelial cells during development of atherosclerotic lesions. In this study, we investigated the potential of different adiponectin subfractions with special emphasis on globular adiponectin (gAd) to recognize and visualize atherosclerotic lesions.

METHODS

Recombinant mouse gAd and subfractions of full-length adiponectin (ie, trimeric, hexameric, and oligomeric forms) were fluorescence-labeled. Aortas of wild-type and apoprotein E-deficient mice fed a high cholesterol diet were dissected and incubated with the labeled biomarkers. Imaging was performed using confocal laser scanning microscopy.

RESULTS

Confocal laser scanning microscopic images showed that gAd binds more strongly to atherosclerotic plaques than full-length adiponectin subfractions. Further, we showed that gAd accumulates preferentially in endothelial cells and the fibrous cap area of plaques. Here we demonstrate for the first time that gAd recognizes atherosclerotic plaques on aortic sections of apoprotein E-deficient mice.

CONCLUSION

These results suggest that gAd, in addition to its physiological properties, is also suitable as a target molecule for prospective diagnostic strategies in imaging atherosclerotic lesions.

Increased intima-media thickness of the carotid artery in childhood: a systematic review of observational studies

Increased carotid intima-media thickness (cIMT) in adults may be caused by a childhood exposure to cardiovascular risk factors. We systematically reviewed observational studies to determine whether obesity, insulin-dependent diabetes mellitus (IDDM), dyslipidemia (DL), hypertension (HT), and chronic renal failure (CRF) are associated with increased cIMT in children and adolescent patients compared with control subjects. We performed a PubMed literature search from January 1986 to February 2010. Two reviewers separately verified the inclusion criteria of relevant studies for the objective of the review. The data extracted in the patient and control groups were sample size, age, gender, cIMT measurement methods, cIMT values, and statistical analysis results. From 348 citations, 65 cross-sectional studies (2 cited twice) with case-control design met the inclusion criteria: 26 in obesity, 14 in IDDM, 11 in DL, 8 in HT, and 8 in CRF. cIMT measurement protocols varied according to the studies, with measurements being performed on the common carotid artery in 65/67 cases and on the far wall in 57/67 cases. From the 67 studies cited, 22/26 reported a significantly increased cIMT in obese children and adolescents compared with the control group, 8/14 in IDDM patients, 10/11 in DL patients, 7/8 in HT patients, and 8/8 in CRF patients.

CONCLUSION

Despite the heterogeneity of ultrasound measurement methods, cIMT was significantly increased in 55 out of the 67 cited studies, confirming early vascular damages in pediatric populations with an increased future risk for vascular diseases.

Inflammatory adipokines, high molecular weight adiponectin, and insulin resistance: a population-based survey in prepubertal schoolchildren

Background

The aim of this study was to investigate sex differences and associations of high molecular weight (HMW) adiponectin, leptin and proinflammatory adipokines, individually or in combinations, with adiposity and insulin resistance (IR) measures in prepubertal childhood.

Methodology

We studied 305 prepubertal children (boys/girls: 144/161; Tanner stage 1; age: 5-13 yr), included in a cohort of 44,231 adolescents who participated in an extensive Italian school-based survey. According to Cole's criteria, 105 individuals were lean (L; boys/girls: 59/46), 60 overweight (OW; boys/girls: 32/28) and 140 obese (OB; boys/girls: 70/70). Measurements comprised total and HMW adiponectin, leptin, as well as a panel of proinflammatory adipokines/chemokines associated with diabetes risk.

Principal Findings

Leptin-, and the leptin-to-HMW adiponectin ratio (L/HMW)-, increased progressively (p<0.0001) from L to OW to OB boys and girls. When compared with L peers, OW and OB girls exhibited lower (p<0.001) HMW adiponectin levels, while in boys the HMW multimers did not differ significantly across the BMI-stratified groups. OB girls displayed higher (p<0.05) IL-8, IL-18, monocyte chemoattractant protein-1 (MCP-1) and soluble intercellular adhesion molecule-1 levels (sICAM-1) than L girls, whereas increased macrophage migration inhibitory factor (MIF) concentrations in OB vs OW boys were seen. HMW adiponectin (negatively), leptin or inflammatory markers (positively) correlated with adiposity and IR measures. In multivariate models, leptin represented a strong and independent determinant of HOMA-IR (R² 0.378; p<0.01). Adjustment for age, BMI_z-score, lipids and inflammatory mediators abolished the association between leptin and HOMA-IR in boys, while in girls leptin remained still a significant predictor of IR (R² 0.513; p<0.01). Finally, in both sexes, the joint effect of the L/HMW did not improve the prediction of basal IR as compared with leptin levels alone, which were mainly explained by the BMI_z-score.

Conclusions

In prepubertal children, leptin emerges as a sex-independent discrimination marker of adiposity degree and as a useful, sex-associated predictor of the systemic insulin resistance.

Plasma adiponectin concentration and left ventricular hypertrophy in kidney transplant patients

BACKGROUND

Low plasma adiponectin concentration is associated with more frequent occurrence of left ventricular hypertrophy (LVH) and more exaggerated intima-media thickness of common carotid artery (IMT). IMT is an early surrogate marker of atherosclerosis. This study aimed to assess the relationship between plasma adiponectin concentration and left ventricular mass index (LVMI) and IMT in kidney transplant patients (KTP).

METHODS

In 88 adult KTP, plasma adiponectin concentration, LVMI, and IMT were estimated. LVH was defined as LVMI >110 or >125 g/m(2) for females and males, respectively. Data presented are means and 95% CI.

RESULTS

Plasma adiponectin concentration was similar in KTP with (n = 42) or without LVH (n = 46) (13.5 [11.4-15.6] vs. 13.1 [11.6-14.6] μg/mL, respectively), as well as in KTP subgroups divided according to the IMT value tertiles (p = 0.42) (11.7 [10.0-13.3], 14.2 [11.7-16.6], and 14.0 [11.7-16.4] μg/mL in the lowest, middle, and highest tertiles, respectively). Plasma glucose concentrations were similar in KTPs with LVH or without LVH. No significant correlation was found between plasma adiponectin concentration and both LVMI (R = -0.02; p = 0.87) and IMT (R = 0.09; p = 0.38), respectively.

CONCLUSION

Results of this cross-sectional study do not confirm the roles of low adiponectin and high glucose in the pathogenesis of LVH and atherosclerosis in KTP.

Glucose-based peritoneal dialysis solution suppresses adiponectin synthesis through oxidative stress in an experimental model of peritoneal dialysis

OBJECTIVE

Accumulation of visceral fat is one of the major risk factors for the development of cardiovascular disease in peritoneal dialysis (PD) patients. Adiponectin, an adipokine commonly regarded as a negative indicator of metabolic disease, is reported to be downregulated in its gene level in end-stage renal disease patients. Since excessive fat deposit is involved in increased reactive oxygen species (ROS), PD solution (PDS) may contribute to ROS production, resulting in dysregulation of adiponectin. In this study, we tested our hypothesis that oxidative stress induced by PDS may play a role in the regulation of adiponectin.

METHODS

Commercial PDS containing 3.86% glucose (20 - 30 mL) was administered to SD rats for 12 weeks with and without N-acetylcysteine (NAC; 10 mmol/L). ELISA was used to quantify adiponectin in plasma and spent dialysate. For in vitro studies, fully differentiated 3T3-L1 adipocytes and adipocytes isolated from abdominal fat were treated with a high glucose solution, PDS, and H(2)O(2). Adiponectin levels in the conditioned media were measured by ELISA and immunoblot assays. The mRNA levels of adiponectin in mature adipocytes were examined using real-time RT-PCR.

RESULTS

The levels of adiponectin in plasma and spent dialysate were significantly downregulated by PDS and this effect was suppressed by NAC. In 3T3-L1 adipocytes, adiponectin secretion was inhibited by 50 mmol/L glucose, PDS diluted 2-fold, and H(2)O(2) (200 μmol/L). In addition, H(2)O(2) downregulated expression of adiponectin mRNA and secretion of adiponectin oligomer complexes.

CONCLUSIONS

Our data suggest that ROS induced by conventional glucose-based PDS may contribute to pathophysiological changes in abdominal fat and downregulate adiponectin secreted from adipocytes during long-term PD.

Haemostatic alterations in overweight children: associations between metabolic syndrome, thrombin generation, and fibrinogen levels

BACKGROUND

The metabolic syndrome (MetS) is associated with central obesity and leads to increased morbidity and mortality due to cardiovascular disease (CVD). Since obesity is associated with a hypercoagulable state, it has been speculated that hypercoagulation is linking MetS to CVD.

METHODS

We prospectively examined 81 overweight children and 32 normal-weight children aged 10-16 years. We analyzed blood pressure, fasting lipids, glucose, insulin, fibrinogen, and thrombin generating test determining time to peak (TTPeak), peak, time preceding the thrombin burst (lag-time), and 'endogenous' thrombin potential (ETP).

RESULTS

Overweight children demonstrated significantly higher fibrinogen levels (p<0.001), shorter lag-time (p<0.001), and TTPeak (p=0.038) compared to normal-weight children. Furthermore, ETP (p<0.001) and peak (p<0.001) were significantly higher in overweight than in normal-weight children. Fibrinogen and all parameters of the clotting test correlated significantly (p always <0.05) to body mass index (BMI) but not significantly to insulin resistance index HOMA-IR or occurrence of MetS in multiple linear backward regression analyses adjusted for age and gender.

CONCLUSIONS

The increased fibrinogen levels and the changes in the thrombin generation test points towards a haemostatic alteration in overweight children. The parameters of the clotting test were related to the degree of overweight but not to insulin resistance or occurrence of MetS questioning a direct association between MetS and the coagulation system. Longitudinal studies are needed to confirm these findings.

Cardiovascular risk factors, nonalcoholic fatty liver disease, and carotid artery intima-media thickness in an adolescent population in southern Italy

The objective of this study was to determine, in an adolescent population, the prevalence of nonalcoholic fatty liver disease (NAFLD) and the association of NAFLD and cardiovascular risk factors with carotid artery intima-media thickness (IMT), a marker of subclinical atherosclerosis. The authors conducted a population-based study among 642 randomly selected adolescents aged 11-13 years in Reggio Calabria, southern Italy, between November 2007 and October 2008. Prevalences of overweight and obesity were 30.5% and 13.5%, respectively. The overall prevalence of NAFLD was 12.5%, increasing to 23.0% in overweight/obese adolescents. In univariate analysis, increased IMT was positively associated with the presence of NAFLD, body mass index (BMI), waist circumference, systolic blood pressure (all P's < 0.001), diastolic blood pressure (P = 0.006), gamma-glutamyl transpeptidase (P = 0.006), alanine aminotransferase (P = 0.007), and C-reactive protein (P = 0.008) and was inversely associated with high density lipoprotein cholesterol (P < 0.001). In multivariate analysis, NAFLD (P = 0.002), BMI (P = 0.004), waist circumference (P = 0.003), and systolic blood pressure (P = 0.005) retained significant associations. The authors conclude that NAFLD, BMI, waist circumference, and systolic blood pressure are independent markers of increased IMT in a random sample of adolescents.

Vascular health in children and adolescents: effects of obesity and diabetes

The foundations for cardiovascular disease in adults are laid in childhood and accelerated by the presence of comorbid conditions, such as obesity, diabetes, hypertension, and dyslipidemia. Early detection of vascular dysfunction is an important clinical objective to identify those at risk for subsequent cardiovascular morbidity and events, and to initiate behavioral and medical interventions to reduce risk. Typically, cardiovascular screening is recommended for young adults, especially in people with a family history of cardiovascular conditions. Children and adolescents were once considered to be at low risk, but with the growing health concerns related to sedentary lifestyle, poor diet and obesity, cardiovascular screening may be needed earlier so that interventions to improve cardiovascular health can be initiated. This review describes comorbid conditions that increase cardiovascular risk in youth, namely obesity and diabetes, and describes noninvasive methods to objectively detect vascular disease and quantify vascular function and structure through measurements of endothelial function, arterial compliance, and intima-media thickness. Additionally, current strategies directed toward prevention of vascular disease in these populations, including exercise, dietary interventions and pharmacological therapy are described.