Relationship between nonalcoholic fatty liver disease prevalence and visceral fat in obese adolescents

Characterization of hepatic fatty acids using magnetic resonance spectroscopy for the assessment of treatment response to metformin in an eNOS-/- mouse model of metabolic nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide. Liver biopsy remains the gold standard for diagnosis and staging of disease. There is a clinical need for noninvasive diagnostic tools for risk stratification, follow-up, and monitoring treatment response that are currently lacking, as well as preclinical models that recapitulate the etiology of the human condition. We have characterized the progression of NAFLD in eNOS^-/- mice fed a high fat diet (HFD) using noninvasive Dixon-based magnetic resonance imaging and single voxel STEAM spectroscopy-based protocols to measure liver fat fraction at 3 T. After 8 weeks of diet intervention, eNOS^-/- mice exhibited significant accumulation of intra-abdominal and liver fat compared with control mice. Liver fat fraction measured by ¹ H-MRS in vivo showed a good correlation with the NAFLD activity score measured by histology. Treatment of HFD-fed NOS3^-/- mice with metformin showed significantly reduced liver fat fraction and altered hepatic lipidomic profile compared with untreated mice. Our results show the potential of in vivo liver MRI and ¹ H-MRS to noninvasively diagnose and stage the progression of NAFLD and to monitor treatment response in an eNOS^-/- murine model that represents the classic NAFLD phenotype associated with metabolic syndrome.

Discriminatory capacity of obesity indicators as predictors of high liver fat in US adolescents

BACKGROUND

The aims of this study were to assess the potential of 16 anthropometric, body composition and endocrine indexes as predictors of high liver fat and determine the most appropriate cut-off points in US adolescents.

METHODS

A cross-sectional study was conducted on a population of 816 adolescents aged 12-17 years. The FibroScan^® 502V2 device was used to estimate the controlled attenuation parameter (CAP). Body fat percentage, fat mass, trunk fat percentage and trunk fat mass were measured by dual-energy X-ray absorptiometry. Anthropometric data and metabolic parameters were determined. Receiver operating characteristic curves were analysed to estimate the optimal cut-off points that best identify adolescents with high liver fat (CAP ≥90th percentile).

RESULTS

In boys, triponderal mass index (TMI) had the highest area under curve (AUC) value (0.865) and the optimal cut-off score for TMI was 17.47 kg/m³ , which had 81.32 sensitivity and 82.99 specificity. In girls, trunk fat index (TFI) had the highest AUC value (0.826) and its optimal cut-off score in screening for high liver fat was 3.76 kg/m² , which had 74.04 sensitivity and 88.03 specificity. Fat mass index (FMI) index had the second highest AUC values (0.863 in boys 0.812 in girls) in both sex; the cut-off point for the detection of high liver fat was <8.66 kg/m² for girls and <7.45 kg/m² for boys.

CONCLUSION

Assessment of TMI in boys, TFI in girls, and FMI in both sexes are low-cost and easy-to-use parameters that may be useful as early screening tools for possible high liver fat in adolescents.

Hepatic Steatosis in Patients With Single Ventricle and a Fontan Circulation

Background

Hepatic steatosis, caused by nonalcoholic fatty liver disease, is a leading cause of chronic liver disease. The interplay between hepatic steatosis and the development of liver disease following the Fontan procedure is not well understood. This study examined the prevalence and associations of hepatic steatosis in patients with a Fontan circulation.

Methods and Results

This was a single‐center retrospective study of 95 patients with a Fontan circulation with liver magnetic resonance imaging performed between 2012 and 2019. The average age at magnetic resonance imaging was 21.5±8.5 years. The percent liver fat signal was determined using magnetic resonance chemical shift‐encoded proton density fat fraction imaging. Hepatic steatosis was defined as liver fat ≥5% and was present in 10.5% of the cohort. The presence of hepatic steatosis was associated with higher body mass index (29±4 versus 24±6 kg/m², P=0.006), a higher frequency of obesity (50% versus 12%, P=0.015), lower high‐density lipoprotein cholesterol (35±9 versus 43±14 mg/dL, P=0.050), and greater subcutaneous fat thickness (2.6±0.7 versus 1.8±1.0 cm, P=0.043). There was no association between hepatic steatosis and cardiovascular imaging or hemodynamic variables from cardiac catheterization.

Conclusions

Risk factors for hepatic steatosis in patients with Fontan circulation include obesity and dyslipidemia, similar to what is seen in the general population. Fontan hemodynamics were not associated with hepatic steatosis.

Consumption of High-Fructose Corn Syrup Compared with Sucrose Promotes Adiposity and Increased Triglyceridemia but Comparable NAFLD Severity in Juvenile Iberian Pigs

BACKGROUND

Fructose consumption has been linked to nonalcoholic fatty liver disease (NAFLD) in children. However, the effect of high-fructose corn syrup (HFCS) compared with sucrose in pediatric NAFLD has not been investigated.

OBJECTIVES

We tested whether the isocaloric substitution of dietary sucrose by HFCS would increase the severity of NAFLD in juvenile pigs, and whether this effect would be associated with changes in gut histology, SCFA production, and microbial diversity.

METHODS

Iberian pigs, 53-d-old and pair-housed in pens balanced for weight and sex, were randomly assigned to receive a mash diet top-dressed with increasing amounts of sucrose (SUC; n = 3 pens; 281.6-486.8 g/kg diet) or HFCS (n = 4; 444.3-724.8 g/kg diet) during 16 wk. Diets exceeded the animal's energy requirements by providing sugars in excess, but met the requirements for all other nutrients. Animals were killed at 165 d of age after blood sampling, and liver, muscle, and gut were collected for histology, metabolome, and microbiome analyses. Data were analyzed by multivariate and univariate statistics.

RESULTS

Compared with SUC, HFCS increased subcutaneous fat, triacylglycerides in plasma, and butyrate in colon (P ≤ 0.05). In addition, HFCS decreased UMP and short-chain acyl carnitines in liver, and urea nitrogen and creatinine in serum (P ≤ 0.05). Microbiome analysis showed a 24.8% average dissimilarity between HFCS and SUC associated with changes in SCFA-producing bacteria. Body weight gain, intramuscular fat, histological and serum markers of liver injury, and circulating hormones, glucose, and proinflammatory cytokines did not differ between diets.

CONCLUSIONS

Fructose consumption derived from HFCS promoted butyrate synthesis, triglyceridemia, and subcutaneous lipid deposition in juvenile Iberian pigs, but did not increase serum and histological markers of NAFLD compared with a sucrose-enriched diet. Longer studies could be needed to observe differences in liver injury among sugar types.

Body composition, phenotype and central obesity indices in Egyptian women with non-alcoholic fatty liver disease

OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. The aim of this study is to investigate body composition and phenotype of Egyptian women with non-alcoholic fatty liver disease (NAFLD) and compare with those without and determine the optimal cut-off values of central obesity indices for predicting NAFLD.

METHODS

The study included 100 women with NAFLD and 100 age and sex matched healthy controls without NAFLD. All women were subjected to ultrasonography examination. Anthropometric measurements included weight, height, waist circumference (WC), hip circumference (HC) and skinfolds thickness were assessed for all participants. Body fat % was evaluated by Tanita body composition analyzer. Body mass index (BMI), WC / height ratio (WHtR), WC / HC ratio (WHR) and visceral adiposity index (VAI) were calculated. Receiver-operating characteristic (ROC) curve was used to determine the optimal cut-off values.

RESULTS

Data showed significant higher levels of WHtR, WHR, BMI, sum of skinfolds, body fat %, serum fasting blood lipids and glucose in NAFLD women compared to group of patients without NAFLD. The area under curve (AUC) was 0.920 for VIA, 0.883 for WHtR and 0.647 for WHR. The optimal cutoff value of VAI was 3.66, of WHtR was 0.66 and WHR was 0.84. All values showed high sensitivity and specificity values.

CONCLUSION

NAFLD women were obese, had excess subcutaneous fat and body fat ratio. Central obesity indices are closely associated with the presence of NAFLD in Egyptian women and might be responsible for its development. Visceral adiposity index had superior diagnostic performance.

Metabolically healthy overweight adolescents: definition and components

PURPOSE

In adolescents, the definition and clinical implications of metabolically healthy overweight (MHO) status have not been established. This study aimed to investigate the prevalence of MHO according to its most widespread definition, which is based on metabolic syndrome (MS), and to explore further metabolic indicators such as Homeostatic Model Assessment of Insulin Resistance, total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, and C-reactive protein levels, together with metabolic health predictors in a sample of adolescents attending a pediatric obesity clinic.

METHODS

Data from 487 adolescents categorized as overweight (52.6% females, 88.1% white), with a mean body mass index (BMI) z-score of 2.74 (±1.07 standard deviation [SD]), and a mean age of 14.4 years (±2.2 SD) were cross-sectionally analyzed. From this original sample, a subsample of 176 adolescents underwent a second assessment at 12 (±6 SD) months for longitudinal analysis.

RESULTS

From the 487 adolescents originally analyzed, 200 (41.1%) were categorized as MHO, but only 93 (19.1%) had none of the metabolic indicators considered in this study. According to longitudinal analysis, 30 of the 68 adolescents (44%) categorized as MHO at baseline became non-MHO over time. BMI z-score was the best predictor of metabolic health both in cross-sectional and longitudinal analyses. Increased BMI z-score reduced the odds of being categorized as MHO (odds ratio [OR], 0.6; 95% confidence interval [CI], 0.4-0.9; P=.008) and increased the odds of having hypertension (OR 2.1, 95% CI: 1.4-3.3, P=0.001), insulin resistance (OR, 2.4; 95% CI, 1.4-4.1, P=0.001), or a proinflammatory state (OR, 1.2; 95% CI, 1.1-1.3, P=0.002).

CONCLUSION

Diagnosis of MHO should not be exclusively based on MS parameters, and other metabolic indicators should be considered. Adolescents categorized as overweight should participate in weight-management lifestyle interventions regardless of their metabolic health phenotype.

Free-breathing Magnetic Resonance Imaging Assessment of Body Composition in Healthy and Overweight Children: An Observational Study

OBJECTIVE

Conventional, breath-holding magnetic resonance imaging (MRI) assesses body composition by measuring fat volumes and proton density fat fraction (PDFF). However, breath-holding MRI is not always feasible in children. This study's objective was to use free-breathing MRI to quantify visceral and subcutaneous fat volumes and PDFFs and correlate these measurements with hepatic PDFF.

METHODS

This was an observational, hypothesis-forming study that enrolled 2 groups of children (ages 6-17 years), healthy children and overweight children with presumed nonalcoholic fatty liver disease. Free-breathing MRI was used to measure visceral and subcutaneous fat volumes and PDFFs, and hepatic PDFF. Imaging biomarkers were compared between groups, and correlations coefficients (r) and coefficients of determination (R) were calculated.

RESULTS

When compared with the control group (n = 10), the overweight group (n = 9) had greater mean visceral (1843 vs 329 cm, P < 0.001) and subcutaneous fat volumes (7663 vs 893 cm, P < 0.001), as well as greater visceral (80% vs 45%, p < 0.001) and subcutaneous fat PDFFs (89% vs 75%, P = 0.003). Visceral fat volume (r = 0.79, P < 0.001) and PDFF (r = 0.92, P < 0.001) correlated with hepatic PDFF. In overweight subjects, for each unit increase in visceral fat PDFF, hepatic PDFF increased by 2.64%; visceral fat PDFF explained 54% of hepatic PDFF variation (R = 0.54, P = 0.02).

CONCLUSIONS

In this study, we used free-breathing MRI to measure body composition in children. Future studies are needed to investigate the possible value of subcutaneous and visceral fat PDFFs, and validate free-breathing MRI body composition biomarkers.

Effects of magnitude of visceral adipose tissue reduction: Impact on insulin resistance, hyperleptinemia and cardiometabolic risk in adolescents with obesity after long-term weight-loss therapy

AIM

To investigate the association between visceral adipose tissue loss and insulin resistance and hyperleptinemia in adolescents with obesity submitted to interdisciplinary weight-loss therapy.

METHODS

A total of 172 post-pubertal adolescents (body mass index greater than the 95th percentile of the Centers for Disease Control and Prevention reference growth charts) were recruited for the study. The adolescents were assigned to long-term weight-loss therapy. Body composition, visceral and subcutaneous fat, glucose metabolism, lipid profile, hepatic enzymes and leptin concentration were measured. After the therapy, the adolescents were allocated to three different groups according to the tertile of visceral fat reduction.

RESULTS

Positive effects on body composition were observed in all analysed groups independent of visceral fat reduction. It was found that visceral fat was an independent predictor of insulin resistance in the investigated population. Obese adolescents who lost a higher proportion of visceral adipose tissue (>1.8 cm) demonstrated improved metabolic and inflammatory parameters twice as much than those who presented smaller losses. Positive correlations between visceral fat reduction and glucose metabolism, lipid profile, hepatic enzymes and homeostasis model assessment of insulin resistance index were demonstrated.

CONCLUSION

The magnitude of the reduction in visceral fat was an independent predictor of insulin resistance, hyperleptinemia and metabolic disorders related to obese adolescents.

Body image as risk factor for emotional and behavioral problems among Chinese adolescents

BACKGROUND

Being overweight and obesity during adolescence are worldwide public health problems. This study examined the relationship between actual weight, body image, and emotional and behavioral problems among Chinese adolescents.

METHODS

A total of 3841 adolescents (age range, 11-16 years) from 5 Chinese cities were included in this cross-sectional study. All of the study participants were asked to complete questionnaires (including demographic features, strengths and difficulties questionnaires, pubertal development scale), and their height and weight were measured at the same time. Body image was measured in two ways: self-perceived weight and body satisfaction. The relationship between weight status and mental health was estimated by multivariate logistic regression for boys and girls.

RESULTS

Our study showed a difference by sex for prevalence of being overweight/obesity and body dissatisfaction among Chinese adolescents. Boys were more likely to be overweight or obese than girls (30.4% vs. 21.5%, p < 0.05), but girls were more likely to be dissatisfied with their bodies than boys (41.2% vs. 27.9%, p < 0.05). In the logistic regression, body image, not actually being overweight, was significantly associated with a higher risk of emotional and behavioral problems. Compared to perceived normal weight boys, boys who perceived themselves as underweight had an increased likelihood of emotional problems (adjusted odds ratio [OR] = 1.73; 95% confidence interval (CI), 1.16-2.57), conduct problems (OR = 1.73; 95% CI, 1.20-2.50), and total difficulties (OR = 1.50; 95% CI, 1.09-2.05). Compared to body satisfaction, body dissatisfaction was a risk factor for emotional problems (boys: OR = 2.80; 95% CI, 1.84-4.25; girls: OR = 2.18; 95% CI, 1.42-3.36), conduct problems (boys: OR = 1.87, 95% CI, 1.26-2.76; girls: OR = 2.79; 95% CI, 1.46-5.30), hyperactivity problems (boys: OR = 1.67; 95% CI, 1.09-2.55; girls: OR = 2.04; 95% CI, 1.13-3.69), and total difficulties (boys: OR = 2.03; 95% CI, 1.45-2.84; girls: OR = 2.30; 95% CI, 1.46-3.56).

CONCLUSIONS

Being overweight and obese during adolescence are very serious public health problems in China. Body image was a more substantial predictor for adolescent emotional and behavioral problems than actually being overweight/obesity.

Ultrasonographic measurement of liver, portal vein, hepatic vein and perivisceral adipose tissue in high-yielding dairy cows with fatty liver during the transition period

The aim of the present study was to evaluate the potential for diagnosis of fatty liver by means of ultrasonographic measurement of liver and perivisceral adipose tissue as an alternative to blood indicators of lipomobilization and liver biopsy in periparturient high-yielding dairy cows. Thirty cows were enrolled and divided into two groups. The evaluation of body condition score (BCS), non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHB), liver and perivisceral adipose tissue ultrasonographic measurement and histological liver lipid content (GdL) was performed at 15 ± 5 d prepartum (T0), 10 ± 2 d postpartum (T1), 30 ± 2 d postpartum (T2) and 50 ± 2 d postpartum (T3). Mesenteric fat thickness (the thickness of the perivascular adipose tissue) measured on ultrasound was shown to be an independent determinant of fatty liver. The cut-off of the ultrasonographic evaluation of the liver may be useful as a first and practical approach in identifying fatty liver. In conclusion, a non-invasive and reliable diagnostic method for predicting the risk of fatty liver in high yielding dairy cows has been demonstrated.

Effects of exercise intervention on visceral fat in obese children and adolescents

INTRODUCTION

This meta-analysis study was aimed to assess the effects of exercise intervention on visceral fat in obese children and adolescents.

EVIDENCE ACQUISITION

Electronic database searches were performed in Academic Search Complete, CINAHL, Healthsource, MEDLINE, and SportDiscus, and from the earliest record to November 2017. Keywords included "exercise or training," "visceral fat," and "child or adolescent or youth." The inclusion criteria for eligible studies were as follows: 1) subjects were obese at baseline; 2) aged 6-19 years; 3) visceral fat was reported at baseline and after an intervention; and 4) studies were published in peer-reviewed journals written in English.

EVIDENCE SYNTHESIS

A total of 207 studies were observed at the initial search and 73 effect sizes (ESs) were derived from the 34 selected studies. The overall exercise intervention effect was large (Cohen's d [ES]=-1.003, 95% CI=-1.114, -0.892). Moderator analyses results showed that gender (Qb=8.23, df=2, P=0.016), exercise type (Qb=10.68, df=2, P=0.005), and intervention length (Qb=24.71, df=2, P<0.001) influenced the overall ES.

CONCLUSIONS

The group of both boys and girls (ES=-0.95) who participated combined exercise program (Aerobic + Resistance training; ES=-1.17) for 12 months (ES=-1.24) appeared to be the most effective exercise strategy for reducing visceral fat in obese youth.

Effects of Exercise Training Alone on Depot-Specific Body Fat Stores in Youth: Review of Recent Literature

The prevalence of childhood obesity has increased at an alarming rate. The increased obesity rate in pediatrics parallels the increased risks for developing metabolic abnormalities, such as insulin resistance, type 2 diabetes, and nonalcoholic fatty liver disease. In particular, the strong relationship between obesity and such health consequences is well explained by the excessive accumulation of depot-specific body adiposity, such as visceral adipose tissue, intrahepatic lipid content, intermuscular adipose tissue, and/or intramyocellular lipid content. Limited evidence suggests that both aerobic and resistance exercise alone, independent of weight loss, can be an effective therapeutic strategy for improving risk markers of metabolic abnormalities as well as inducing positive changes in depot-specific body adiposity in obese children and adolescents. However, the independent role of exercise alone (without calorie restriction) in body fat distribution is still unclear, and the results are less conclusive in pediatrics. In this brief review, the effects of aerobic and resistance exercise on depot-specific body adiposity changes in children and adolescents are discussed.

Infant feeding practices and dietary consumption of US infants and toddlers: National Health and Nutrition Examination Survey (NHANES) 2003–2012

Objective

To compare infant and toddler anthropometric measurements, feeding practices and mean nutrient intakes by race/ethnicity and income.

Design

Cross-sectional analysis using general linear modelling. Ten years of survey data (2003–2012) were combined to compare anthropometric measurements, feeding practices and mean nutrient intakes from a nationally representative US sample.

Setting

The 2003–2012 National Health and Nutrition Examination Survey (NHANES).

Subjects

Infants and toddlers (n 3669) aged 0–24 months.

Results

Rates of overweight were higher among Mexican-American infants and toddlers (P=0·002). There were also several differences in feeding practices among groups based on race/ethnicity. Cessation of breast-feeding occurred earlier for non-Hispanic black and Mexican-American v. non-Hispanic white infants (3·6 and 4·2 v. 5·3 months; P<0·0001; P=0·001). Age at first feeding of solids was earlier for white than Mexican-American infants (5·3 v. 5·7 months; P=0·02). There were differences in almost all feeding practices based on income, including the lowest-income infants stopped breast-feeding earlier than the highest-income infants (3·2 v. 5·8 months, P<0·0001). Several differences in mean nutrient intakes by both race/ethnicity and income were also identified.

Conclusions

Our study indicates that disparities in overweight, feeding practices and mean nutrient intakes exist among infants and toddlers according to race/ethnicity, which cannot be disentangled from income.

Obese Children with Metabolic Syndrome Have 3 Times Higher Risk to Have Nonalcoholic Fatty Liver Disease Compared with Those without Metabolic Syndrome

BACKGROUND

The aim of this study was to investigate the relationship between metabolic syndrome (MS) and nonalcoholic fatty liver disease (NAFLD) in obese children. One hundred and twenty-five subjects aged 11-12 years old participated in the study.

METHODS

Anthropometric and biochemical indices were measured, including lipid and liver profile, blood glucose, serum insulin, and liver ultrasound.

RESULTS

Forty-four children (58.6%) were found to have MS. Insulin resistance was present in 78 (62.4%) children. Patients with MS were more likely to have NAFLD (P < 0.001). Children with NAFLD had significantly higher body mass index, waist circumference, triglycerides, fasting insulin, and lower high-density lipoprotein compared to patients with normal livers (P < 0.001). Insulin resistance was significantly higher in children with NAFLD (P < 0.001). Obese children presenting with MS were 3.01 (2.87-3.57, P < 0.002) times more likely to develop NAFLD compared to those without metabolic syndrome after adjustment of cofounders.

CONCLUSIONS

Obese children with MS have a higher risk of developing NAFLD. Weight management and early prevention should be the first line of treatment to prevent any possible health issues later on.

Inulin oligofructose attenuates metabolic syndrome in high-carbohydrate, high-fat diet-fed rats

Prebiotics alter bacterial content in the colon, and therefore could be useful for obesity management. We investigated the changes following addition of inulin oligofructose (IO) in the food of rats fed either a corn starch (C) diet or a high-carbohydrate, high-fat (H) diet as a model of diet-induced metabolic syndrome. IO did not affect food intake, but reduced body weight gain by 5·3 and 12·3 % in corn starch+inulin oligofructose (CIO) and high-carbohydrate, high-fat with inulin oligofructose (HIO) rats, respectively. IO reduced plasma concentrations of free fatty acids by 26·2 % and TAG by 75·8 % in HIO rats. IO increased faecal output by 93·2 %, faecal lipid excretion by 37·9 % and weight of caecum by 23·4 % and colon by 41·5 % in HIO rats. IO improved ileal morphology by reducing inflammation and improving the density of crypt cells in HIO rats. IO attenuated H diet-induced increases in abdominal fat pads (C 275 (sem 19), CIO 264 (sem 40), H 688 (sem 55), HIO 419 (sem 32) mg/mm tibial length), fasting blood glucose concentrations (C 4·5 (sem 0·1), CIO 4·2 (sem 0·1), H 5·2 (sem 0·1), HIO 4·3 (sem 0·1) mmol/l), systolic blood pressure (C 124 (sem 2), CIO 118 (sem 2), H 152 (sem 2), HIO 123 (sem 3) mmHg), left ventricular diastolic stiffness (C 22·9 (sem 0·6), CIO 22·9 (sem 0·5), H 27·8 (sem 0·5), HIO 22·6 (sem 1·2)) and plasma alanine transaminase (C 29·6 (sem 2·8), CIO 32·1 (sem 3·0), H 43·9 (sem 2·6), HIO 33·6 (sem 2·0) U/l). IO attenuated H-induced increases in inflammatory cell infiltration in the heart and liver, lipid droplets in the liver and plasma lipids as well as impaired glucose and insulin tolerance. These results suggest that increasing soluble fibre intake with IO improves signs of the metabolic syndrome by decreasing gastrointestinal carbohydrate and lipid uptake.

Obstructive sleep apnea predisposes to nonalcoholic Fatty liver disease in patients with polycystic ovary syndrome

OBJECTIVE

Some studies have shown a higher prevalence of nonalcoholic fatty liver disease (NAFLD) and obstructive sleep apnea (OSA) in patients with polycystic ovary syndrome (PCOS). The objective of this study was to assess NAFLD in PCOS women with and without OSA. A possible role of high serum androgen levels in the development of OSA in PCOS women was also investigated.

METHODS

Biochemical, hormonal, and polysomnography parameters were determined in 38 premenopausal PCOS patients. NAFLD was evaluated by ultrasound. Testosterone was measured by an immunoassay.

RESULTS

Serum androgen levels and the prevalence of NAFLD (83.3% vs. 26.9%; P<.001) were higher in patients with OSA than those without OSA. The mean apnea-hypopnea index (AHI) was higher in patients with NAFLD than in those without NAFLD (16.87 events [ev]/h vs. 1.57 ev/h; P<.002). On multivariate logistic regression, where body mass index ≥30 kg/m2, homeostasis model assessment for insulin resistance ≥2.7, and OSA (AHI ≥5 ev/h) were independent variables, only OSA was an independent predictor of NAFLD (odds ratio [OR], 7.63; P = .044). Free testosterone levels ≥1.07 ng/dL were also independently associated with OSA (OR, 8.18; P = .023).

CONCLUSION

In PCOS women, the occurrence of OSA strongly predisposes them to development of NAFLD and a worse metabolic profile; hence, treatment of OSA might be beneficial for NAFLD.

Waist circumference as a marker for screening nonalcoholic fatty liver disease in obese adolescents

Objective:

To assess the relationship between the degree of waist circumference (WC) and nonalcoholic fatty liver disease (NAFLD) in obese adolescents of both genders, analyzed according to quartiles of WC.

Methods:

Cross-sectional study that involved 247 obese adolescents aged 12–19 years. Mean values of the nutritional parameters and serum analyses were compared with the groups using the independent t-test. Pearson correlation coefficient was used to determine the relationship of the parameters studied. Chi-square test for trend was used to determine the relationship between the prevalence of the NAFLD and WC quartile by gender.

Results:

NAFLD were presented in 60% of the study participants. Obese adolescents in the 3rd and 4th quartiles of WC presented higher prevalence of NAFLD when compared with that in the 1st quartile in both genders. The NAFLD patients had significantly higher values for body weight, BMI (body mass index), BAZ-score (BMI-for-age z-scores), total fat (% and kg), WC, visceral fat, insulin, insulin resistance index (HOMA-IR), aspartate aminotransferase and alanine aminotransferase, when compared with non-NAFLD obese adolescents.

Conclusions:

In conclusion, the results presented here suggest that an increase in WC can reliably predict the risk of NAFLD in obese adolescents. This is a low cost and easy-to-use tool that can help in screening in adolescents.

Relationship between visceral obesity and plasma fibrinogen in obese children

BACKGROUND

The prevalence of obesity in children and adolescents has increased significantly worldwide with an alarming rise of its co-morbidities. The excess of visceral adipose tissue is associated with hypertension, prothrombotic and pro-inflammatory states. Our aim was to find a possible association between visceral obesity and plasma fibrinogen, as one of the cardiovascular risk factors, in obese children.

METHODS

Forty-three obese children and 40 non-obese controls were studied regarding their history, complete physical examination, anthropometric assessment, body composition analysis, ultrasonographic measurement of visceral adipose tissue and subcutaneous fat as well as laboratory measurement of plasma fibrinogen.

RESULTS

Our study revealed significant higher levels of fibrinogen in obese children than controls (14.5+5.1 and 2.9+0.52 mg/mL, respectively) with p-value <0.01. Moreover, the obese group had statistically significant difference in visceral fat (5.96+0.77 cm) and subcutaneous fat (2.66+0.70 cm) than controls (2.45+0.65 and 0.70+0.18 mg/mL, respectively) with p-value <0.01. In addition, fibrinogen had significant positive correlation with body mass index (r=0.327), waist/hip ratio (r=0.394), fat percentage (r=0.301), visceral adipose tissue (r=0.323) and subcutaneous fat (r=0.301).

CONCLUSIONS

There was highly significant increase in the fibrinogen level, visceral and subcutaneous abdominal fat in the obese group with insignificant sex differences. Fibrinogen had a significant positive correlation with the different adiposity markers, blood pressure, visceral and subcutaneous fat. Visceral adipose tissue is a stronger predictor for cardiovascular risk compared to subcutaneous fat.

[Waist circumference as a marker for screening nonalcoholic fatty liver disease in obese adolescents]

OBJECTIVE

To assess the relationship between the degree of waist circumference (WC) and nonalcoholic fatty liver disease (NAFLD) in obese adolescents of both genders, analyzed according to quartiles of WC.

METHODS

Cross-sectional study that involved 247 obese adolescents aged 12-19 years. Mean values of the nutritional parameters and serum analyses were compared with the groups using the independent t-test. Pearson correlation coefficient was used to determine the relationship of the parameters studied. Chi-square test for trend was used to determine the relationship between the prevalence of the NAFLD and WC quartile by gender.

RESULTS

NAFLD were presented in 60% of the study participants. Obese adolescents in the 3rd and 4th quartiles of WC presented higher prevalence of NAFLD when compared with that in the 1st quartile in both genders. The NAFLD patients had significantly higher values for body weight, BMI (body mass index), BAZ-score (BMI-for-age z-scores), total fat (% and kg), WC, visceral fat, insulin, insulin resistance index (HOMA-IR), aspartate aminotransferase and alanine aminotransferase, when compared with non-NAFLD obese adolescents.

CONCLUSIONS

The results presented here suggest that an increase in WC can reliably predict the risk of NAFLD in obese adolescents. This is a low cost and easy-to-use tool that can help in screening in adolescents.

Phenotype, Body Composition, and Prediction Equations (Indian Fatty Liver Index) for Non-Alcoholic Fatty Liver Disease in Non-Diabetic Asian Indians: A Case-Control Study

OBJECTIVE

In this study, we have attempted comparison of detailed body composition phenotype of Asian Indians with non-alcoholic fatty liver disease (NAFLD) vs. those without, in a case controlled manner. We also aim to analyse prediction equations for NAFLD for non-diabetic Asian Indians, and compare performance of these with published prediction equations researched from other populations.

METHODS

In this case-control study, 162 cases and 173 age-and sex-matched controls were recruited. Clinical, anthropometric, metabolic, and body composition profiles, and liver ultrasound were done. Fasting insulin levels, value of homeostasis model assessment of insulin resistance (HOMA-IR), and serum high sensitive C-reactive protein (hs-CRP) levels were evaluated. Multivariate logistic and linear regression analyses were used to arrive at prediction equations for fatty liver [Indian fatty liver index (IFLI)].

RESULTS

As compared to those without fatty liver, those with fatty liver exhibited the following; Excess dorsocervical fat ('Buffalo hump'), skin tags, xanthelasma, 'double chin', arcus; excess total, abdominal and subcutaneous adiposity, and high blood pressure, blood glucose, measures of insulin resistance (fasting insulin and HOMA-IR values), lipids and hs-CRP levels. Two prediction equations were developed; Clinical [Indian Fatty Liver Index-Clinical; IFLI-C]: 1(double chin) +15.5 (systolic blood pressure) +13.8 (buffalo hump); and IFLI-Clinical and Biochemical (CB): serum triglycerides+12 (insulin)+1(systolic blood pressure) +18 (buffalo hump). On ROC Curve analysis, IFLI performed better than all published prediction equations, except one.

CONCLUSION

Non-diabetic Asian Indians with NAFLD researched by us were overweight/obese, had excess abdominal and subcutaneous fat, multiple other phenotypic markers, had higher insulin resistance, glycemia, dyslipidemia and subclinical inflammation than those without. Prediction score developed by us for NAFLD; IFLI-C and IFLI-CB, should be useful for clinicians and researchers.

Sonographic evaluation of visceral and subcutaneous fat in obese children

Objective

To evaluate sonographic measurements of visceral and subcutaneous fat in children, and to investigate the usefulness of preperitoneal fat (PF) and the abdominal wall fat index (AFI) as parameters to determine visceral fat and presence of nonalcoholic fatty liver disease (NAFLD) in obese children.

Materials and Methods

A case-control study of a sample including 44 children (22 cases and 22 controls) matched by sex and age. The Student t test and the Fisher exact test were utilized in the descriptive and bivariate analysis.

Results

The sonographic parameters evaluated - subcutaneous cell tissue, PF and intraperitoneal fat, and NAFLD - presented high statistical association with body mass index. NAFLD was observed in eight obese patients (36.36%), and PF and AFI were the variables with highest statistical significance, with p < 0.0001.

Conclusion

Ultrasonography is useful tool in the differentiation and quantification of visceral and subcutaneous fat in children. The measures of PF and AFI are useful in the assessment of visceral fat and NAFLD in obese children.

Adipocyte exosomes induce transforming growth factor beta pathway dysregulation in hepatocytes: a novel paradigm for obesity-related liver disease

BACKGROUND

The pathogenesis of nonalcoholic fatty liver disease (NAFLD) has been attributed to increased systemic inflammation and insulin resistance mediated by visceral adipose tissue (VAT), although the exact mechanisms are undefined. Exosomes are membrane-derived vesicles containing messenger RNA, microRNA, and proteins, which have been implicated in cancer, neurodegenerative, and autoimmune diseases, which we postulated may be involved in obesity-related diseases. We isolated exosomes from VAT, characterized their content, and identified their potential targets. Targets included the transforming growth factor beta (TGF-β) pathway, which has been linked to NAFLD. We hypothesized that adipocyte exosomes would integrate into HepG2 and hepatic stellate cell lines and cause dysregulation of the TGF-β pathway.

METHODS

Exosomes from VAT from obese and lean patients were isolated and fluorescently labeled, then applied to cultured hepatic cell lines. After incubation, culture slides were imaged to detect exosome uptake. In separate experiments, exosomes were applied to cultured cells and incubated 48-h. Gene expression of TGF-β pathway mediators was analyzed by polymerase chain reaction, and compared with cells, which were not exposed to exosomes.

RESULTS

Fluorescent-labeled exosomes integrated into both cell types and deposited in a perinuclear distribution. Exosome exposure caused increased tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and integrin ανβ-5 expression and decreased matrix metalloproteinase-7 and plasminogen activator inhibitor-1 expression in to HepG2 cells and increased expression of TIMP-1, TIMP-4, Smad-3, integrins ανβ-5 and ανβ-8, and matrix metalloproteinase-9 in hepatic stellate cells.

CONCLUSIONS

Exosomes from VAT integrate into liver cells and induce dysregulation of TGF-β pathway members in vitro and offers an intriguing possibility for the pathogenesis of NAFLD.

Prevalence, risk factors, and predictors of nonalcoholic fatty liver disease among schoolchildren: a hospital-based study in Alexandria, Egypt

BACKGROUND AND STUDY AIMS

Nonalcoholic fatty liver disease (NAFLD) is an emerging problem in children and adolescents worldwide. This study was done to investigate the prevalence of NAFLD in children and adolescents as well as to determine the associated risk factors of fatty liver and to explore the ability of some obesity indices to predict and consequently be used as a screening method of fatty liver disease at certain cutoff points in schoolchildren.

PATIENTS AND METHODS

A cross-sectional, nested case-control study was carried out. Cases and controls were randomly selected from outpatient schoolchildren aged 6-18years attending the radiology clinic at Sporting Health Insurance Paediatric Hospital in Alexandria. They were subjected to ultrasonic examination as well as complete anthropometric and laboratory measurements including fasting plasma glucose (FPG) level, fasting insulin, alanine aminotransferase (ALT) level, and lipid profile.

RESULTS

Fatty liver was prevalent in schoolchildren (15.8%) and increased significantly with age (p=0.004). Positive family history of diabetes mellitus (DM), hypertension (HTN), obesity, and liver disease were all statistically significant risk factors for fatty liver. Waist circumference (WC), body mass index (BMI) and its Z-score were significantly sensitive predictors. BMI was considered the best predictor of paediatric NAFLD at a cutoff=22.9. NAFLD was significantly associated with high triglycerides (TGs), low high-density lipoprotein cholesterol (HDL), homoeostatic model assessment (HOMA) percentile, and the number of metabolic syndrome (MS) components.

CONCLUSION

Paediatric NAFLD is a substantial problem in schoolchildren and has a close relationship with obesity, dyslipidaemia, insulin resistance (IR), and consequently MS. BMI and WC can be used as useful predictors and screening tools for NAFLD in schoolchildren.

Grading scale of visceral adipose tissue thickness and their relation to the nonalcoholic fatty liver disease

CONTEXT

The mesenteric fat is drained by the portal system, being related to the metabolic syndrome which is an impor-tant risk factor for non-alcoholic fatty liver disease (NAFLD).

OBJECTIVES

Graduate of visceral fat thickness and correlate with the NAFLD degree through ultrasonography method.

METHODS

We studied 352 subjects for age, gender, measures of subcutaneous fat thickness and visceral fat thickness as well as the presence and degree of liver fatty. Was analyzed the independent relationship between visceral fat thickness and NAFLD, and linear regression analysis was used in order to predict the visceral fat thickness from subcutaneous fat thickness.

RESULTS

The mean age of 225 women (63.9%) and 127 men (36.1%) was 47.5 ± 14.0 (18-77) years, 255 subjects had normal examinations, 97 had NAFLD thus distributed, 37 grade 1, 32 grade 2, and 28 grade 3. The subcutaneous fat thickness ranged from 0.26 to 3.50 cm with a mean of 1.3 ± 0.6 cm and visceral fat thickness ranged from 0.83 to 8.86 cm with a mean of 3.6 ± 1.7 cm. Linear regression showed that for every increase of 1 cm in subcutaneous fat thickness the visceral fat thickness will increase 0.9 cm.

CONCLUSIONS

The visceral fat thickness measured by ultrasonography is a useful and seems to be able to help estimate the risk of NAFLD.

Aerobic plus resistance training was more effective in improving the visceral adiposity, metabolic profile and inflammatory markers than aerobic training in obese adolescents

The purpose of this study was to determine whether aerobic plus resistance training (AT + RT) is more effective than aerobic training (AT) at reducing inflammatory markers and cardiovascular risk in obese adolescents. A total of 139 obese adolescents were enrolled, aged 15-19 years, body mass index (BMI) ≥ 95th percentile and participated in 1 year of interdisciplinary intervention. They were randomised into two groups: AT (n = 55), AT + RT (n = 61). Blood samples were collected to analyse glycaemia, insulin, the lipid profile, leptin and adiponectin concentrations. Insulin resistance was measured by homeostasis model assessment of insulin resistance index (HOMA-IR). The AT + RT group showed better results with regard to decreased body fat mass, low-density lipoprotein concentration (LDL-c) levels, subcutaneous and visceral fat and increased body lean mass. Indeed, a reduction of hyperleptinaemia and an increase in adiponectin concentrations, promoting an improvement in the leptin/adiponectin ratio, was observed. Important clinical parameters were improved in both types of exercise; however, AT + RT was more effective in improving the visceral adiposity, metabolic profile and inflammatory markers than AT alone, suggesting clinical applications for the control of intra-abdominal obesity and cardiovascular risk in the paediatric population.

Dietary determinants of hepatic steatosis and visceral adiposity in overweight and obese youth at risk of type 2 diabetes

BACKGROUND

Dietary determinants of hepatic steatosis, an important precursor for nonalcoholic fatty liver disease, are undefined.

OBJECTIVE

We explored the roles of sugar and fat intake as determinants of hepatic steatosis and visceral obesity in overweight adolescents at risk of type 2 diabetes.

DESIGN

This was a cross-sectional study of dietary patterns and adipose tissue distribution in 74 overweight adolescents (aged: 15.4 ± 1.8 y; body mass index z score: 2.2 ± 0.4). Main outcome measures were hepatic steatosis (≥5.5% fat:water) measured by magnetic resonance spectroscopy and visceral obesity (visceral-to-subcutaneous adipose tissue ratio ≥0.25) measured by magnetic resonance imaging. Main exposure variables were dietary intake and habits assessed by the Harvard Youth Adolescent Food Frequency Questionnaire.

RESULTS

Hepatic steatosis and visceral obesity were evident in 43% and 44% of the sample, respectively. Fried food consumption was more common in adolescents with hepatic steatosis than in adolescents without hepatic steatosis (41% compared with 18%; P = 0.04). Total fat intake (β = 0.51, P = 0.03) and the consumption of >35% of daily energy intake from fat (OR: 11.8; 95% CI: 1.6, 86.6; P = 0.02) were both positively associated with hepatic steatosis. Available carbohydrate (β = 0.54, P = 0.02) and the frequent consumption of soda were positively associated with visceral obesity (OR: 6.4; 95% CI: 1.2, 34.0; P = 0.03). Daily fiber intake was associated with reduced odds of visceral obesity (OR: 0.82; 95% CI: 0.68, 0.98; P = 0.02) but not hepatic steatosis.

CONCLUSION

Hepatic steatosis is associated with a greater intake of fat and fried foods, whereas visceral obesity is associated with increased consumption of sugar and reduced consumption of fiber in overweight and obese adolescents at risk of type 2 diabetes.

Body composition variables as predictors of NAFLD by ultrasound in obese children and adolescents

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a disorder associated with excessive fat accumulation, mainly in the intra-abdominal region. A simple technique to estimate abdominal fat in this region could be useful to assess the presence of NAFLD, in obese subjects who are more vulnerable to this disease. The aim of this cross-sectional study was to verify the reliability of waist circumference and body composition variables to identify the occurrence of NAFLD in obese children and adolescents.

METHODS

Sample was composed of 145 subjects, aged 11 to 17 years. Assessments of waist circumference (WC), trunk fat mass (TFM) and fat mass (FM) by dual-energy X-ray absorptiometry (DXA) and ultrasound for diagnosis of NAFLD and intra-abdominal adipose tissue (IAAT) were used. Correlation between variables was made by Spearman's coefficients; ROC curve parameters (sensitivity, specificity, area under curve) were used to assess the reliability of body composition variables to assess the presence of NAFLD. Statistical significance was set at 5%.

RESULTS

Significant correlations were observed between NAFLD and WC (p = 0.001), TFM (p = 0.002) and IAAT (p = 0.001). The higher values of area under the ROC curve were for WC (AUC = 0.720), TFM (AUC = 0.661) and IAAT (AUC = 0.741).

CONCLUSIONS

Our findings indicated that TFM, IAAT and WC present high potential to identify NAFLD in obese children and adolescents.

Cut-Off Values of Visceral Adiposity to Predict NAFLD in Brazilian Obese Adolescents

Objectives. The present study aimed at determining cut-off points of visceral fat to predict NAFLD and analyzed metabolic disorders of obese adolescents. Methods. Cross-sectional study involved 165 obese adolescents ranged in age from 15 to 19 years. Glycemia, hepatic transaminases, lipid profile, and insulin resistance were analyzed. Visceral and subcutaneous fat were measured by ultrasound and body composition by plesthysmography. Results. The NAFLD adolescents had significantly higher values for body mass, BMI-for-age, BMI, total fat, waist circumference, and visceral fat when compared with non-NAFLD obese adolescents in both genders. Moreover, there were significant positive correlations between visceral fat with the variables BMI-for-age (r = 0.325,), TG (r = 0.277), AST (r = 0.509), ALT (r = 0.519), WC (r = 0.390), and visceral/subcutaneous ratio (r = 0.790) for NAFLD group. Total fat, triglycerides, and visceral fat were the independent predictors to NAFLD. Analysis of the ROC curves revealed cut-off points of visceral fat of 4.47 cm for girls and 4.21 cm for boys. Conclusions. The results may suggest that abdominal ultrasonography procedure may be a safe alternative method of assessing visceral adiposity aiming to be considered to the development of preventive and treatment strategies in obese individuals. This clinial trial is registered with ClinicalTrial.gov (NCT01358773).

Childhood obesity: a review of increased risk for physical and psychological comorbidities

BACKGROUND

Worldwide estimates of childhood overweight and obesity are as high as 43 million, and rates continue to increase each year. Researchers have taken interest in the childhood obesity epidemic and the impact of this condition across health domains. The consequences of childhood and adolescent obesity are extensive, including both medical and psychosocial comorbidities.

OBJECTIVE

The purpose of this review was to consolidate and highlight the recent literature on the comorbidities associated with childhood obesity, both nationally and internationally.

METHODS

PubMed and PsychINFO searches were conducted on childhood obesity and comorbidities.

RESULTS

The initial search of the terms obesity and comorbidity yielded >5000 published articles. Limits were set to include studies on children and adolescents that were published in peer-reviewed journals from 2002 to 2012. These limits narrowed the search to 938. Review of those articles resulted in 79 that are included in this review. The major medical comorbidities associated with childhood obesity in the current literature are metabolic risk factors, asthma, and dental health issues. Major psychological comorbidities include internalizing and externalizing disorders, attention-deficit hyperactivity disorder, and sleep problems.

CONCLUSIONS

The high prevalence rates of childhood obesity have resulted in extensive research in this area. Limitations to the current childhood obesity literature include differential definitions of weight status and cut-off levels for metabolic risk factors across studies. Additionally, some results are based on self-report of diagnoses rather than chart reviews or physician diagnosis. Even so, there is substantial support for metabolic risk factors, internalizing disorders, attention-deficit hyperactivity disorder, and decreased health-related quality of life as comorbidities to obesity in childhood. Additional investigations on other diseases and conditions that might be associated with childhood obesity are warranted and intervention research in this area is critical.

The effect of weight loss magnitude on pro-/anti-inflammatory adipokines and carotid intima-media thickness in obese adolescents engaged in interdisciplinary weight loss therapy

BACKGROUND

Obesity is a chronic disease defined by an excess amount of adipose tissue and presents a low-grade inflammatory state, increasing cardiovascular risk.

OBJECTIVE

To assess the effect of weight loss magnitude on the inflammatory profile and carotid intima-media thickness (cIMT) in obese adolescents engaged in interdisciplinary therapy.

DESIGN AND PATIENTS

Seventy-seven postpubertal obese adolescents with a BMI greater than the 95th percentile (37·18 ± 5·14), of both genders and between the ages of 14 and 19 years (16·74 ± 1·59) were subjected to a 1-year period of interdisciplinary intervention (nutrition, psychology, physical exercise and clinical support).

MEASUREMENTS

Blood samples were collected to analyse glucose, lipid and adipokine concentrations. Body composition, anthropometric profiles and cIMT were measured. The results are presented according to quartiles of weight loss: 1st (≤5·80 kg) = low; 2nd (5·80-10·90 kg) = low to moderate; 3rd (10·90-15·90 kg) = moderate; and 4th (>15·90 kg) = massive.

RESULTS

Leptin, the leptin/adiponectin ratio and plasminogen activator inhibitor 1 (PAI-1) were decreased significantly in the low-to-moderate weight loss. The cIMT was reduced in the moderate weight loss. Moreover, adiponectin was increased only in the massive weight loss. Additionally, weight loss was an independent predictor of changes in leptin level, the adiponectin/leptin ratio (A/L ratio) and PAI-1 when the data were adjusted for age and gender. BMI changes were predictors of changes in leptin and PAI-1 levels. A/L ratio was associated with lean body mass (%), independent of gender and age. In addition, changes in A/L ratio were independent predictors of cIMT alterations.

CONCLUSIONS

Interdisciplinary therapy may reduce cardiovascular risk factors among adolescents depending on their degree of weight loss (moderate to massive) and when correlated with their inflammatory profile, metabolic state and cIMT.

Morphological and metabolic determinants of nonalcoholic fatty liver disease in obese youth: a pilot study

Background

Nonalcoholic fatty liver disease (NAFLD) related to obesity has been rising in the last decades, though the morphological and metabolic determinants are remain unclear in children. The aim of this study was to analyze the morphological determinants and metabolic abnormalities in obese children and adolescents, classified either as with (P-NAFLD) or without (N-NAFLD). The sample comprised 190 individuals, aged 6 to 16 years-old, assigned into one of 4 groups according to sex and presence or absence of NAFLD. Obesity was obtained according to body mass index (BMI) cut-points. Body composition variables was estimated by Dual-Energy X-ray Absorptiometry (DEXA). Total cholesterol (TC), triglycerides (TG), HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), insulin, fasting glucose (FG) and blood pressure were also analyzed. The diagnosis of NAFLD, as well as the measurement of intra-abdominal fat tissue thickness (IAF) and subcutaneous abdominal fat tissue thickness (SCF), was carried-out by ultrasound.

Results

Males and females belonging to P-NAFLD group showed, respectively, higher TFM and IAF. When data were adjusted for sex, age and total fat mass, those in P-NAFLD showed statistically higher IAF, TFM and TG.

Conclusion

Our study showed that obese youngsters who were assigned to P-NAFLD group were twice as likely to present higher concentration of triglycerides, higher levels of trunk fat, as well as intra-abdominal fat compared to their N-NAFLD counterparts even after adjustments for sex, age, pubertal stage and total body fat mass.

The role of pro/anti-inflammatory adipokines on bone metabolism in NAFLD obese adolescents: effects of long-term interdisciplinary therapy

To investigate the role of pro- and anti-inflammatory adipokines in the bone metabolism of non-alcoholic fatty liver disease (NAFLD) obese adolescents as well as the effects of long-term interdisciplinary therapy on metabolic-related risk factors. Forty post-puberty obese adolescents were randomly assigned into two groups: (1) NAFLD group and (2) non-NAFLD group (diagnosis by ultrasonography) and submitted to a weight loss therapy. Body composition was analyzed by air displacement plethysmography, bone mineral density (BMD) and content by dual-energy X-ray absorptiometry, blood samples were collected to measure lipid profile, hepatic enzymes, and adipokines. Leptin and adiponectin concentrations were measured by ELISA. A decrease in total body mass, BMI, body fat, visceral and subcutaneous fat, insulin concentration, HOMA-IR, total cholesterol and an increase in lean body mass were observed in both groups after therapy. It was found positive correlation between the Δ BMD and the Δ fat mass (%) (r = 0.31, P = 0.01) and negative correlations between Δ BMC with Δ HOMA-IR (r = -0.34, P = 0.02) and Δ HOMA-IR with Δ leptin (r = -0.34, P = 0.02). In addition, increased levels of adiponectin and reduction in leptin concentrations were observed in NAFLD group. In the simple regression analysis, the HOMA-IR was an independent predictor changes in BMC in total obese adolescents and in the non-NAFLD group. One year of interdisciplinary weight loss therapy for obese adolescents with or without NAFLD, could regulate bone mineral metabolism as result of an increased BMC and improved inflammatory state.

Long-term effects of aerobic plus resistance training on the adipokines and neuropeptides in nonalcoholic fatty liver disease obese adolescents

OBJECTIVE

To compare the effects of aerobic training (AT) with aerobic plus resistance training (AT+RT) in nonalcoholic fatty liver disease (NAFLD) obese adolescents.

DESIGN

Long-term interdisciplinary weight-loss therapy (1 year of clinical, nutritional, psychological, and exercise-related intervention).

PARTICIPANTS

Fifty-eight postpubertal obese adolescents were randomized to AT or AT+RT according to NAFLD diagnosis. Adipokine and neuropeptide concentrations were measured by enzyme-linked immunosorbent assay, visceral fat by ultrasound, and body composition by plethysmography.

RESULTS

The NAFLD group that followed the AT+RT protocol presented lower insulin, homeostasis model assessment-insulin resistance (HOMA-IR), and alanine transaminase (ALT) values after intervention compared with AT. It was verified that there was a higher magnitude of change in the subcutaneous fat, glycemia, total cholesterol (TC), low-density lipoprotein-cholesterol, ALT, and adiponectin in response to AT+RT than in the control group (AT). All patients who underwent the AT+RT exhibited significantly higher adiponectin, leptin, and Δadiponectin and lower melanin-concentrating hormone (MCH) concentrations after therapy compared with the AT group. In the simple linear regression analysis, changes in glycemia, insulin, and HOMA-IR were independent predictors of significant improvement in adiponectin concentration. Indeed, ΔAST (aspartate transaminase) and ΔGGT (γ-glutamyl transpeptidase) were independent predictors of ΔALT, while Δfat mass and ΔAgRP (agouti-related protein) were independent predictors of ΔMCH. Although the number of patients was limited, we showed for the first time the positive effects of AT+RT protocol in a long-term interdisciplinary therapy to improve inflammatory biomarkers and to reduce orexigenic neuropeptide concentrations in NAFLD obese adolescents.

CONCLUSION

The long-term interdisciplinary therapy with AT+RT protocol was more effective in significantly improving noninvasive biomarkers of NAFLD that are associated with the highest risk of disease progression in the pediatric population.

Influence of visceral and subcutaneous fat in bone mineral density of obese adolescents

OBJECTIVE

To verify the influence of visceral and subcutaneous fat, as well adipokines in bone mineral density (BMD) in obese adolescents.

SUBJECTS AND METHODS

The study involved 125 postpubertal obese adolescents (45 boys and 80 girls). Anthropometric measurements, body composition, visceral and subcutaneous fat, and BMD were determined. Leptin, adiponectin, and insulin levels also analyzed.

RESULTS

Data demonstrated a negative relationship between BMD with insulin resistance, visceral fat and leptin concentration; and bone mineral content with visceral/subcutaneous ratio. Positive association between BMD and subcutaneous fat was observed.

CONCLUSIONS

Visceral fat and insulin resistance, as well as visceral/subcutaneous ratio and leptin concentration, were negative predictors of BMD in boys and girls, respectively. However, subcutaneous fat had a protective influence in BMD only in boys.

The role of pro/anti-inflammatory adipokines on bone metabolism in NAFLD obese adolescents: effects of long-term interdisciplinary therapy

To investigate the role of pro- and anti-inflammatory adipokines in the bone metabolism of non-alcoholic fatty liver disease (NAFLD) obese adolescents as well as the effects of long-term interdisciplinary therapy on metabolic-related risk factors. Forty post-puberty obese adolescents were randomly assigned into two groups: (1) NAFLD group and (2) non-NAFLD group (diagnosis by ultrasonography) and submitted to a weight loss therapy. Body composition was analyzed by air displacement plethysmography, bone mineral density (BMD) and content by dual-energy X-ray absorptiometry, blood samples were collected to measure lipid profile, hepatic enzymes, and adipokines. Leptin and adiponectin concentrations were measured by ELISA. A decrease in total body mass, BMI, body fat, visceral and subcutaneous fat, insulin concentration, HOMA-IR, total cholesterol and an increase in lean body mass were observed in both groups after therapy. It was found positive correlation between the Δ BMD and the Δ fat mass (%) (r = 0.31, P = 0.01) and negative correlations between Δ BMC with Δ HOMA-IR (r = -0.34, P = 0.02) and Δ HOMA-IR with Δ leptin (r = -0.34, P = 0.02). In addition, increased levels of adiponectin and reduction in leptin concentrations were observed in NAFLD group. In the simple regression analysis, the HOMA-IR was an independent predictor changes in BMC in total obese adolescents and in the non-NAFLD group. One year of interdisciplinary weight loss therapy for obese adolescents with or without NAFLD, could regulate bone mineral metabolism as result of an increased BMC and improved inflammatory state.

The association of metabolic syndrome, insulin resistance and non-alcoholic fatty liver disease in overweight/obese children

BACKGROUND/AIM

To study the prevalence of metabolic syndrome (MS), insulin resistance (IR) and non-alcoholic fatty liver disease (NAFLD) in overweight/obese children with clinical hepatomegaly and/or raised alanine aminotransferase (ALT).

PATIENTS AND METHODS

Thirty-three overweight and obese children, aged 2-13 years, presenting with hepatomegaly and/or raised ALT, were studied for the prevalence of MS, IR and NAFLD. Laboratory analysis included fasting blood glucose, serum insulin, serum triglycerides (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c) and liver biochemical profile, in addition to liver ultrasound and liver biopsy.

RESULTS

Twenty patients (60.6%) were labeled with MS. IR was present in 16 (48.4%). Fifteen (44%) patients had biopsy-proven NAFLD. Patients with MS were more likely to have NAFLD by biopsy (P=0.001). Children with NAFLD had significantly higher body mass index, waist circumference, ALT, total cholesterol, LDL-c, TG, fasting insulin, and lower HDL-c compared to patients with normal liver histology (P< 0.05) and fitted more with the criteria of MS (80% vs. 44%). IR was significantly more common among NAFLD patients (73% vs. 28%).

CONCLUSION

There is a close association between obesity, MS, IR and NAFLD. Obese children with clinical or biochemical hepatic abnormalities are prone to suffer from MS, IR and NAFLD.

Attenuation of fatty liver and prevention of hypercholesterolemia by extract of Curcuma longa through regulating the expression of CYP7A1, LDL-receptor, HO-1, and HMG-CoA reductase

The extract of Curcuma longa, better known as turmeric, was orally administered to experimental rats that were fed a high-cholesterol diet to investigate whether it could regulate plasma lipids and cholesterol levels and possibly improve hepatic conditions. With turmeric supplements, rats showed a significant decrease in total plasma cholesterol and low-density lipoprotein cholesterol but an increase in high-density lipoprotein cholesterol when compared with rats that were fed a high-cholesterol diet alone. Fatty liver developed in hypercholesterolemic rats with the high-cholesterol diet treatment, and this condition was markedly improved when rats were provided with turmeric supplements at 100 mg/kg or 300 mg/kg of body mass. The turmeric treatment resulted in a significant decrease in the total amount of hepatic lipid. Histological staining of liver tissues with Sudan III and hematoxylin showed that rats fed with a high-cholesterol diet alone had more and larger granular fat bodies than rats having turmeric extract supplementation in their high-cholesterol diet. Reverse-transcription polymerase chain reaction was used to assess the expression levels of enzymes involved in fat metabolism and cellular homeostasis in experimental rat livers. The results showed that rats fed a high-cholesterol diet supplemented with turmeric extract had a significant increase in the expression of cholesterol 7 α-hydroxylase, hemeoxygenase 1, and low-density lipoprotein receptors but a significant decrease in 3-hydroxy-3-methyl-glutaryl-CoA reductase level when compared with rats fed a normal or high-cholesterol diet, showing that turmeric prevents hypercholesterolemia and the formation of fatty liver by the modulation of expressions of enzymes that are important to cholesterol metabolism.

PRACTICAL APPLICATION

  Turmeric may be considered a functional food for regulating plasma cholesterol levels and preventing the development of fatty liver in people who frequently consume a high-cholesterol diet.

Gender-specific differences in adipose distribution and adipocytokines influence adolescent nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a predominantly adult-diagnosed disorder. Knowledge regarding the epidemiology, phenotype, and metabolic risk factors, during adolescence is limited. We sought to determine the prevalence, phenotype, and predictors of NAFLD in 1170 community-based adolescents in the Western Australian Pregnancy Cohort (Raine) Study (the Raine Cohort) who underwent a cross-sectional assessment that included questionnaires, anthropometry, cardiovascular examinations, blood tests, and abdominal ultrasound examinations. Among the 1170 adolescents assessed, the prevalence of NAFLD was 12.8%. Females compared with males had a significantly higher prevalence of NAFLD (16.3% versus 10.1%, P = 0.004) and central obesity (33.2% versus 9.9%, P < 0.05). The severity of hepatic steatosis was associated with the body mass index, waist circumference, subcutaneous adipose tissue thickness (SAT), serum leptin level, homeostasis model assessment for insulin resistance score (P < 0.001 for all), and serum alanine aminotransferase level (P < 0.005) in both genders, but it was associated with increasing visceral adipose tissue thickness (VAT; P < 0.001) and decreasing serum adiponectin levels (P < 0.05) in males alone. Males and females with NAFLD had similar amounts of SAT (P > 0.05); however, in comparison with females with NAFLD, males with NAFLD had greater VAT, a more severe metabolic phenotype with higher glucose levels and systolic blood pressure and lower adiponectin and high-density lipoprotein cholesterol levels (P < 0.001 for all), and greater measures of liver injury (alanine aminotransferase and aspartate aminotransferase, P < 0.001 for all). Similarly, metabolic syndrome was more common in males than females with NAFLD (24% versus 8%, P = 0.01). Suprailiac skinfold thickness predicted NAFLD independently of the body mass index, insulin resistance, and VAT.

CONCLUSION

Gender differences in adolescent NAFLD are related to differences in adipose distribution and adipocytokines. The male phenotype of NAFLD is associated with more adverse metabolic features and greater visceral adiposity than the female phenotype despite the lower prevalence of NAFLD.

Visceral fat decreased by long-term interdisciplinary lifestyle therapy correlated positively with interleukin-6 and tumor necrosis factor-α and negatively with adiponectin levels in obese adolescents

The purpose of this study was to assess the level of cytokine expression in correlation with visceral and subcutaneous fat in obese adolescents admitted to long-term interdisciplinary weight loss therapy. The study was a longitudinal clinical intervention of interdisciplinary therapy. Adolescents (18, aged 15-19 years) with body mass indexes greater than the 95th percentile were admitted and evaluated at baseline and again after 1 year of interdisciplinary therapy. Visceral and subcutaneous fat was analyzed by ultrasonography. Blood samples were collected to analyze tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10), and adiponectin concentrations that were measured by enzyme-linked immunosorbent assay. The most important finding in the present investigation is that the long-term interdisciplinary lifestyle therapy decreased visceral fat. Positive correlations between IL-6 levels and visceral fat (r = 0.42, P < .02) and TNF-α levels and visceral fat (r = 0.40, P < .05) were observed. Negative correlations between TNF-α levels and subcutaneous fat (r = -0.46, P < .01) and adiponectin levels and subcutaneous fat (r = -0.43, P < .03) were also observed. In addition, we found a positive correlation between TNF-α levels and the visceral to subcutaneous fat ratio (r = 0.42, P < .02) and a negative correlation between adiponectin level and the visceral to subcutaneous fat ratio (r = -0.69, P < .001). Despite the limitation of sample size, our results indicate that the observed massive weight loss (mainly visceral fat) was highly correlated with a decreased inflammatory state, suggesting that the interdisciplinary therapy was effective in decreasing inflammatory markers.

The role of anorexigenic and orexigenic neuropeptides and peripheral signals on quartiles of weight loss in obese adolescents

Obesity is characterized as an inflammatory state associated with a modification in the pattern of adipokine secretion. The present study aimed to assess the role of anorexigenic and orexigenic neuropeptides and peripheral signals in obese adolescents submitted to 1 year of weight loss interdisciplinary therapy and grouped according to quartiles of weight loss. A total of 111 post-puberty adolescents, with a BMI >95th percentile, were included. Glycemia and lipid profiles were analyzed. Insulin resistance was estimated by HOMA-IR. Cytokine concentrations were measured by ELISA. The results are presented according to quartiles of weight loss: 1st (<2.5 kg)=low; 2nd (2.5-8 kg)=low to moderate; 3rd (8-14 kg)=moderate; and 4th (>14 kg)=massive. The most important finding was that the NPY concentration increased significantly only in the first phase of weight loss. Moreover, α-MSH variation was an independent factor in explaining the NPY changes during the intervention, confirming the role of the α-MSH concentration in the peripheral control of energy balance in obese adolescents. Indeed, BMI reduction was correlated with increased α-MSH (p<0.05). Massive weight loss promoted a significant increase in α-MSH concentration, and hyperleptinemia was reduced after intervention. All together, our findings, which contribute to our understanding of how orexigenic and anorexigenic systems are regulated by weight loss, will provide insight into the pathogenesis and treatment of obesity and other metabolic diseases, especially in obese adolescents.

Metabolic predictors for early identification of fatty liver using doppler and B-mode ultrasonography in overweight and obese adolescents

(1) to evaluate the frequency of asymptomatic fatty liver disease (FLD) using both Doppler and B-mode ultrasound (US) in overweight and obese adolescents; (2) to compare metabolic findings of fatty liver (FL) assessed by two methods; and (3) to evaluate metabolic predictors of FL shown by these methods. Fifty-nine overweight and obese adolescents aged between 9.0 and 17.0 years and 41 non-obese healthy adolescents were included in this study. B-mode and right hepatic vein Doppler ultrasonography (US) were performed and anthropometric indices, lipid profiles, and adiponectin levels were evaluated in all adolescents. HDL-C levels were significantly lower in patients with FL detected by Doppler US compared to patients without FL (p < 0.05). HDL-C levels were inversely correlated with presence of FL assessed by two methods (r = -0.285, p = 0.004; r = -0.328, p = 0.001, respectively) and adiponectin levels were correlated with presence of FL only detected by B-mode US (r = -0.263, p = 0.008). Adiponectin levels were significantly lower in patients with FL than those without FL assessed by B-Mode US (p = 0.049). Multiple regression analysis revealed that HDL-C levels was the most important predictor of FL assessed by Doppler US (p = 0.027), while body mass index was the determinant of FL assessed by two methods (p < 0.001) in asymptomatic overweight and obese adolescents. It was found that FLD, identified by both B-mode and Doppler US, is seen frequently in asymptomatic overweight and obese adolescents. Elevated BMI is associated with increased risk of FL assessed by two ultrasonographic methods. When using Doppler US, low HDL-C levels can be used as a good predictor for presence of FLD in overweight and obese adolescents.

Insulin resistance and metabolic syndrome in the pediatric population

The metabolic syndrome is a constellation of specific anthropometric, physiological, and biochemical abnormalities predisposing affected individuals to the development of diabetes and cardiovascular disease. The syndrome is well described in the adult literature. However, its description in the pediatric literature is more limited. Due in large part to the normal physiological changes that occur in children and adolescents with respect to growth and puberty, investigators have also struggled to establish a standard definition of the syndrome in the pediatric age group, hindering coordinated research efforts. However, whatever definition of the syndrome is used, the prevalence of the metabolic syndrome in the pediatric age group has increased worldwide. Insulin resistance is the principal metabolic abnormality that is common to the development of the metabolic syndrome in both children and adults. This review summarizes current research regarding the pathophysiology of insulin resistance and how this may contribute to specific abnormalities seen in children and adolescents with the metabolic syndrome. Specifically, insulin resistance in pediatric patients is correlated with cardiovascular risk factors such as elevated blood pressure, dyslipidemia, and type 2 diabetes mellitus, all of which are significant risk factors for adult disease. In addition, current treatment and prevention strategies, including lifestyle modifications, pharmacologic agents, and certain surgical therapies, are highlighted. The need for collaborative changes at the family, school, city, state, and national levels to address the growing prevalence of the metabolic syndrome in the pediatric age group is also reviewed.

Negative correlation between neuropeptide Y/agouti-related protein concentration and adiponectinemia in nonalcoholic fatty liver disease obese adolescents submitted to a long-term interdisciplinary therapy

The complexity pathogenesis in the nonalcoholic fatty liver disease (NAFLD) involves an interplay between adipokines and neuroendocrine regulation of energy balance, including the role of neuropeptide Y (NPY)/agouti-related protein (AgRP) system. The first aim of this study was to assess the effect of long-term interdisciplinary intervention on NAFLD in obese adolescents, and the second objective was to establish the relationship between NPY/AgRP ratio and adiponectinemia. Fifty-five postpuberty obese adolescents were submitted to interdisciplinary intervention. The group was divided between subjects with and without NAFLD (n = 19 and 36, respectively). Blood samples were collected to measure glycemia, hepatic transaminases, lipid profile, insulin resistance, and sensitivity. Adiponectin, NPY, and AgRP concentrations were measured by enzyme-linked immunosorbent assay. Food intake was measured using 3-day diet records. It was observed at baseline that important clinical parameters including body weight, body mass index, visceral fat, homeostasis model assessment of insulin resistance, quantitative insulin sensitivity check index, triglycerides, very low-density lipoprotein cholesterol, and hepatic transaminases were more altered in NAFLD patients. After the intervention, these parameters, total energy, and macronutrient intake were reduced significantly in both groups. The most important finding was the positive correlation between AgRP and visceral fat in all patients and the negative correlation between NPY/AgRP and adiponectinemia only in NAFLD obese adolescents. The NAFLD patients presented more altered clinical parameters than the non-NAFLD subjects, including the negative correlation between adiponectinemia and NPY/AgRP. These results suggested that NAFLD obese adolescents presented an inflammatory profile that can influence the neuroendocrine regulation of energy balance, suggesting an additional impairment in the weight loss therapy.

The role of nutritional profile in the orexigenic neuropeptide secretion in nonalcoholic fatty liver disease obese adolescents

BACKGROUND

Little progress has been made to identify the central neuroendocrine pathway involved in the energy intake control in nonalcoholic fatty liver disease (NAFLD) patients.

OBJECTIVE

To assess the influence of orexigenic neuropeptides in the nutritional aspects of NAFLD obese adolescents submitted to a long-term interdisciplinary approach.

METHODS

Fifty adolescents aged 15-19 years, with body mass index at least 95th percentile, consisting of 25 patients without NAFLD and 25 with NAFLD. The NAFLD diagnosis was determined by ultrasonography. Blood samples were collected to analyze glycemia, hepatic transaminases, and lipid profile. Insulin resistance was estimated by Homeostasis Model Assessment Insulin Resistance Index. Neuropeptide Y (NPY) and agouti related protein concentrations were measured by enzyme-linked immunosorbent assay. Analyses of food intake were made by 3 days recordatory inquiry.

RESULTS

At baseline conditions, the patients with NAFLD had significantly higher values of body mass, body mass index, visceral fat, triglycerides, VLDL-C, and hepatic transaminases. After the long-term intervention, they presented a significant reduction in these parameters. In both the groups, it was observed a significant decrease in energy intake, macronutrients and dietetic cholesterol. Only the patients with NAFLD presented a positive correlation between the saturated fatty acids intake and the orexigenic neuropeptides NPY and agouti related protein, and carbohydrate with NPY. Indeed, it was observed a positive correlation between energy intake, lipid (%) and saturated fatty acids with visceral fat accumulation.

CONCLUSION

Our findings showed an important influence of diet composition in the orexigenic system, being essential consider that the excessive saturated fatty acids intake could be a determinant factor to increase nonalcoholic fatty liver disease.

The role of orexigenic and anorexigenic factors in an interdisciplinary weight loss therapy for obese adolescents with symptoms of eating disorders

AIM

The aim of this study was to evaluate the role of orexigenic and anorexigenic factors in an interdisciplinary weight loss therapy for obese adolescents with symptoms of eating disorders.

METHODS

Thirty-seven post-pubertal, obese adolescents (14 to 19 years old) with symptoms of eating disorders were submitted to long-term interdisciplinary therapy (1 year). Bulimic and binge eating symptoms were measured using the Bulimic Investigatory Test, Edinburgh, and the Binge Eating Scale respectively. Neuropeptide Y, melanin-concentrating hormone, total ghrelin, alpha-melanocyte stimulating hormone and leptin were measured using radioimmunoassay.

RESULTS

After long-term interdisciplinary therapy, the adolescents showed significantly improved body composition, visceral and subcutaneous fat and reduced symptoms of bulimia and binge eating. Intriguingly, orexigenic peptides were up-regulated after short-term therapy and down-regulated at the end of therapy, whereas the anorexigenic pathway was improved with therapy. Furthermore, after long-term therapy, a negative correlation was observed between leptin concentration and melanin-concentrating hormone.

DISCUSSION

We suggest that long-term therapy promotes an intrinsic association between weight loss, improvement of eating disorder symptoms and a decrease in orexigenic factors. Together, these results represent a more effective course by which patients can normalise behaviours related to eating disorders as well the actions of hormones involved in energy balance, and thus advance obesity control.

CONCLUSION

Long-term interdisciplinary therapy was effective to improve anorexigenic and orexigenic factors that influence energy balance and avoid the development of eating disorders in obese adolescents. However, the associations between eating disorders and neuroendocrine factors need to be confirmed in future studies.

Treatment of obese adolescents: the influence of periodization models and ACE genotype

The aims of the present study were to compare the effects of two periodization models on metabolic syndrome risk factors in obese adolescents and verify whether the angiotensin-converting enzyme (ACE) genotype is important in establishing these effects. A total of 32 postpuberty obese adolescents were submitted to aerobic training (AT) and resistance training (RT) for 14 weeks. The subjects were divided into linear periodization (LP, n = 16) or daily undulating periodization (DUP, n = 16). Body composition, visceral and subcutaneous fat, glycemia, insulinemia, homeostasis model assessment of insulin resistance (HOMA-IR), lipid profiles, blood pressure, maximal oxygen consumption (VO(2max)), resting metabolic rate (RMR), muscular endurance were analyzed at baseline and after intervention. Both groups demonstrated a significant reduction in body mass, BMI, body fat, visceral and subcutaneous fat, total and low-density lipoprotein cholesterol, blood pressure and an increase in fat-free mass, VO(2max), and muscular endurance. However, only DUP promoted a reduction in insulin concentrations and HOMA-IR. It is important to emphasize that there was no statics difference between LP and DUP groups; however, it appears that there may be bigger changes in the DUP than LP group in some of the metabolic syndrome risk factors in obese adolescents with regard to the effect size (ES). Both periodization models presented a large effect on muscular endurance. Despite the limitation of sample size, our results suggested that the ACE genotype may influence the functional and metabolic characteristics of obese adolescents and may be considered in the future strategies for massive obesity control.