Liver steatosis in juvenile obesity: correlations with lipid profile, hepatic biochemical parameters and glycemic and insulinemic responses to an oral glucose tolerance test

Population Pharmacokinetics and Dosing Simulations of Intravenous Oxycodone for Perioperative Pain Relief in Adult Surgical Patients with Obesity

BACKGROUND AND OBJECTIVE

Oxycodone, a semisynthetic thebaine derivative µ-opioid (MOP) receptor agonist, is effective for treating moderate and severe pain in different clinical conditions. The pharmacokinetics of intravenous oxycodone in the obese population has not been studied. This study aims to characterize the pharmacokinetic profile of oxycodone after intravenous administration and to simulate an appropriate dosage for analgesic efficacy in obese patients.

METHODS

We recruited 33 (age range from 21 to 72 years) adult patients with a body mass index of 30 kg/m² and above, who were scheduled for non-cardiac surgeries. Intravenous oxycodone was administered after induction of general anesthesia and blood samples were collected up to 24 h after oxycodone administration. Plasma concentrations of oxycodone were assayed using liquid chromatography-tandem mass spectrometry and 253 concentration-time points were used for pharmacokinetic analysis using nonlinear mixed-effects modeling.

RESULTS

Intravenous oxycodone pharmacokinetics were well described by a two-compartment open model. The estimated total clearance and central volume of distribution of oxycodone are 28.5 l/h per 70 kg and 56.4 l per 70 kg, respectively. Total body weight was identified as a significant covariate of the clearance and central volume of distribution. Dosing simulations based on the final model demonstrate that a starting dose of 0.10 mg/kg of intravenous oxycodone is adequate to achieve a target plasma concentration and repeated doses of 0.02 mg/kg may be administered at 1.5-h intervals to maintain a plasma concentration within an effective analgesic range.

CONCLUSIONS

A population pharmacokinetic model using total body weight as a covariate supports the administration of 0.10 mg/kg of intravenous oxycodone as a starting dose and repeated doses of 0.02 mg/kg at 1.5-h intervals to maintain targeted plasma concentrations for analgesia in the obese adult population.

Predictors of hepatic steatosis in living liver donors

Fatty liver disease (steatosis) is considered a risk factor in donor liver transplantation (LT). Macrosteatosis (>50%) is associated with primary graft dysfunction and may reduce long-term recipient survival.

Objective: to identify predictors of macrovesicular steatosis (>50%) by analyzing donor characteristics.

Materials and methods. The retrospective study included 525 potential liver donors between January 1, 2019 and December 31, 2020. Clinical and morphological characteristics of donors were studied using logistic regression and receiver operating characteristic (ROC) analysis. Threshold values of parameters demonstrating statistical significance in multivariate analysis as predictors of >50% hepatic steatosis were obtained by ROC analysis based on calculation of the optimal cutoff point.

Results. Diabetes mellitus (DM), cause of donor’s death (traumatic brain injury), alanine transaminase (ALT) >90 units/L and aspartate transaminase (AST) >110 units/L were predictors of >50% steatosis, revealed by time-zero biopsy in the donor. Almost identical sensitivity and specificity indicators were determined in ROC analysis for liver enzymes – ALT and AST – which were 69.1 and 80.6; 72.2 and 81.1, respectively. Given the obtained values, we can say that with elevated levels of liver enzymes in the donor’s blood, there is a high degree of probability of liver parenchymal damage, but low sensitivity indicates possible multifactoriality of liver damage, and fatty liver disease may be one of the factors, but there may also be no damage to the liver parenchyma. At the same time, the rather high specificity revealed in ROC analysis for liver enzymes is a reliable sign of the absence of fatty liver disease at enzyme values less than the threshold.

Conclusion. The thresholds established for ALT and AST and their corresponding levels of sensitivity and specificity indicate that these parameters have a relatively low predictive level in the context of the presence of severe fatty liver disease in a donor. This allows, nevertheless, to use models built on their basis as screening models in the primary evaluation of liver donors.

Benefits of Physical Exercise as Approach to Prevention and Reversion of Non-Alcoholic Fatty Liver Disease in Children and Adolescents with Obesity

Non-alcoholic fatty liver disease (NAFLD) is an important health concern during childhood; indeed, it is the most frequent cause of chronic liver diseases in obese children. No valid pharmacological therapies for children affected by this condition are available, and the recommended treatment is lifestyle modification, usually including nutrition and exercise interventions. In this narrative review, we summarized up-to-date information on the benefits of physical exercise on NAFLD in children and adolescents with obesity. The role of exercise as non-pharmacological treatment was emphasized in order to provide recent advances on this topic for clinicians not deeply involved in the field. Several studies on obese children and adults confirm the positive role of physical activity (PA) in the treatment of NAFLD, but to date, there are no pediatric randomized clinical trials on exercise versus usual care. Among the pathogenic mechanisms involved in the PA effects on NAFLD, the main players seem to be insulin resistance and related inflammation, oxidative stress, and gut dysbiosis, but further evaluations are necessary to deeply understand whether these factors are correlated and how they synergistically act. Thus, a deeper research on this theme is needed, and it would be extremely interesting.

Antiobesity Activity of Two Polyherbal Formulations in High-Fat Diet-Induced Obese C57BL/6J Mice

Obesity and overweight have posed a severe threat to humanity, needing urgent efforts for the development of safe and effective therapeutic interventions. In this research work, we have developed two polyherbal formulations A and B basically consisting of Helianthus tuberosus root powder (also called inulin of synanthrin) along with other herbs for the treatment of obesity. Evaluation of the antioxidant activity of both formulations using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging assays showed good antioxidant potentials. Both formulations A and B showed good antiobesity activity on a diet-induced obesity (DIO) model of mice by effectively lowering the body weight of mice compared to the high-fat diet (HFD) control mice, mainly by reducing the food efficiency ratio (FER). Furthermore, both formulations ameliorated lipoprotein misbalances induced by obesity and thus decreased the atherogenic index. Treatment with both formulations significantly decreased the liver and epididymal white adipose tissue (WAT) weight. This was supported by the improvement in steatosis of the liver and reduced hypertrophy in WAT on histological examination. In addition, formulations A and B have been seen as effective in controlling fasting blood glucose levels probably by alleviating HFD-induced insulin resistance. All of these results collectively suggest that formulations A and B serve as potentially safe and effective herbal interventions to control obesity and its comorbidities.

Amino Acid-Related Metabolic Signature in Obese Children and Adolescents

The growing interest in metabolomics has spread to the search for suitable predictive biomarkers for complications related to the emerging issue of pediatric obesity and its related cardiovascular risk and metabolic alteration. Indeed, several studies have investigated the association between metabolic disorders and amino acids, in particular branched-chain amino acids (BCAAs). We have performed a revision of the literature to assess the role of BCAAs in children and adolescents' metabolism, focusing on the molecular pathways involved. We searched on Pubmed/Medline, including articles published until February 2022. The results have shown that plasmatic levels of BCAAs are impaired already in obese children and adolescents. The relationship between BCAAs, obesity and the related metabolic disorders is explained on one side by the activation of the mTORC1 complex-that may promote insulin resistance-and on the other, by the accumulation of toxic metabolites, which may lead to mitochondrial dysfunction, stress kinase activation and damage of pancreatic cells. These compounds may help in the precocious identification of many complications of pediatric obesity. However, further studies are still needed to better assess if BCAAs may be used to screen these conditions and if any other metabolomic compound may be useful to achieve this goal.

Compound heterozygous variants in OTULIN are associated with fulminant atypical late-onset ORAS

Autoinflammatory diseases are a heterogenous group of disorders defined by fever and systemic inflammation suggesting involvement of genes regulating innate immune responses. Patients with homozygous loss-of-function variants in the OTU-deubiquitinase OTULIN suffer from neonatal-onset OTULIN-related autoinflammatory syndrome (ORAS) characterized by fever, panniculitis, diarrhea, and arthritis. Here, we describe an atypical form of ORAS with distinct clinical manifestation of the disease caused by two new compound heterozygous variants (c.258G>A (p.M86I)/c.500G>C (p.W167S)) in the OTULIN gene in a 7-year-old affected by a life-threatening autoinflammatory episode with sterile abscess formation. On the molecular level, we find binding of OTULIN to linear ubiquitin to be compromised by both variants; however, protein stability and catalytic activity is most affected by OTULIN variant p.W167S. These molecular changes together lead to increased levels of linear ubiquitin linkages in patient-derived cells triggering the disease. Our data indicate that the spectrum of ORAS patients is more diverse than previously thought and, thus, supposedly asymptomatic individuals might also be affected. Based on our results, we propose to subdivide the ORAS into classical and atypical entities.

Hepatic macrosteatosis in the US pediatric deceased liver donor population

INTRODUCTION

The pediatric obesity epidemic is associated with early development of hepatic macrosteatosis, a hallmark of non-alcoholic fatty LI disease, which is thought to be more rapidly progressive in children than adults. Macrosteatosis in adult allografts is associated with allograft loss, but this has not been examined in pediatric donors.

METHODS

We studied all pediatric potential whole LI donors (2005-2018) who had a LI biopsy in the SRTR (n = 862) and whose LI was transplanted (n = 862). Macrosteatosis was abstracted from biopsy reports and compared to values in the SRTR standard analytic file. Recipients of macrosteatotic pediatric allografts were matched 1:1 to recipients of non-macrosteatotic pediatric allografts by propensity score matching on donor/recipient variables. All-cause allograft loss was estimated via Kaplan-Meier analysis and Cox proportional hazards model.

RESULTS

From 2005 to 2018, the proportion of pediatric donors (age ≥2 years) with obesity increased (14.8% to 21.7%; p < .001), as did the proportion of pediatric deceased whole LI-only donor allografts with macrosteatosis (n = 10 648; 1.8% to 3.9%; p < .001). The median degree of macrosteatosis among macrosteatotic donors was 10% (IQR 5-30). There were no significant differences in all-cause allograft loss between recipients of pediatric LI allografts with and without macrosteatosis at 90 days (p = .11) or 1 year (p = .14) post-transplant in Kaplan-Meier analysis or a Cox proportional hazards model (p > .05).

CONCLUSION

Obese pediatric LI donors have increased over time and were more likely to have hepatic macrosteatosis; however, pediatric macrosteatosis did not appear to adversely affect recipient outcomes.

Evaluation of clinical, endocrine and metabolic findings in obese children with and without hepatosteatosis

OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) is a common obesity-related comorbidity in childhood. In this study, we aimed to evaluate predictors of NAFLD by comparing clinical, endocrine and metabolic findings in obese children with and without hepatosteatosis.

METHODS

Two hundred and eight obese children aged 6-18 years were included. The patients were divided into group 1 (patients with NAFLD, n=94) and group 2 (patients without NAFLD, n=114). Anthropometric measurements, pubertal stage, lipid profiles, fasting glucose and insulin, homeostatic model of assessment for insulin resistance (HOMA-IR), uric acid, total bilirubin, alanine aminotransferase (ALT), blood urea nitrogen, thyroid-stimulating hormone and free thyroxine parameters were compared retrospectively.

RESULTS

The mean body weight, body mass index (BMI), height, tri-ponderal mass index (TMI), insulin, HOMA-IR, triglyceride, ALT and uric acid values were significantly higher, while high-density lipoprotein-cholesterol (HDL-C) values were significantly lower in group 1. The 70.7% of obese children with hepatosteatosis and 83.9% of those without hepatosteatosis were correctly estimated by parameters including age, gender, ALT, HDL-C, fasting insulin and uric acid values.

CONCLUSIONS

Since obesity-associated hepatosteatosis induces various long-term metabolic impacts in children, early detection is of critical importance. Age, gender, TMI, BMI, ALT, HDL-C, fasting insulin and uric acid values may help to predict the risk of hepatosteatosis. Besides, we assessed whether TMI compared to BMI does not have a better utility in estimating obesity-induced hepatosteatosis in children. This is the first study to show the association between TMI and hepatosteatosis in children.

Antihyperlipidemic effect of selected pyrimidine derivatives mediated through multiple pathways

Hyperlipidemia is worth-mentioning risk factor in quickly expanding atherosclerosis, myocardial infarction, and stroke. This study attempted to determine effectiveness of selected pyrimidine derivatives: 5-(3-Hydroxybenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-5), 5-(4-Hydroxybenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-8), 5-(3-Chlorobenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-9), and 5-(4-Chlorobenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-10) against hyperlipidemia. In silico results revealed that SR-5, SR-8, SR-9, and SR-10 exhibited high affinity with 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) possessing binding energy values of -8.2, -8.4, -8.6, and -9.5 Kcal/mol, respectively, and moderate (<-8 Kcal/mol) against other selected targets. In vivo findings showed that test drugs (25 and 50 mg/Kg) significantly decreased HFD rat total cholesterol, triglycerides, low-density lipoprotein, very-low-density lipoprotein, atherogenic index, coronary risk index, alkaline phosphatase, aspartate transaminase, alanine transaminase, and bilirubin and increased high-density lipoprotein (p < 0.05, p < 0.01, p < 0.001 vs HFD group). In animal liver tissues, SR-5, SR-8, SR-9, and SR-10 inhibited HMGCoA reductase enzyme, enhanced glutathione-s-transferase, reduced glutathione, catalase levels, improved cellular architecture in histopathological examination, and decreased expression of inflammatory markers: cyclo-oxygenase 2, tumor necrosis factor alpha, phosphorylated c-Jun N-terminal kinase, and phosphorylated-nuclear factor kappa B, evidenced in immunohistochemistry and enzyme-linked immunosorbent assay molecular investigations. This study indicates that SR-5, SR-8, SR-9, and SR-10 exhibit antihyperlipidemic action, mediated possibly through HMGCoA inhibition, hepatoprotection, antioxidant, and anti-inflammatory pathways.

Non-Alcoholic Fatty Liver Disease in Obese Youth With Insulin Resistance and Type 2 Diabetes

Currently, Non-Alcoholic Fatty Liver Disease (NAFLD) is the most prevalent form of chronic liver disease in children and adolescents worldwide. Simultaneously to the epidemic spreading of childhood obesity, the rate of affected young has dramatically increased in the last decades with an estimated prevalence of NAFLD of 3%-10% in pediatric subjects in the world. The continuous improvement in NAFLD knowledge has significantly defined several risk factors associated to the natural history of this complex liver alteration. Among them, Insulin Resistance (IR) is certainly one of the main features. As well, not surprisingly, abnormal glucose tolerance (prediabetes and diabetes) is highly prevalent among children/adolescents with biopsy-proven NAFLD. In addition, other factors such as genetic, ethnicity, gender, age, puberty and lifestyle might affect the development and progression of hepatic alterations. However, available data are still lacking to confirm whether IR is a risk factor or a consequence of hepatic steatosis. There is also evidence that NAFLD is the hepatic manifestation of Metabolic Syndrome (MetS). In fact, NAFLD often coexist with central obesity, impaired glucose tolerance, dyslipidemia, and hypertension, which represent the main features of MetS. In this Review, main aspects of the natural history and risk factors of the disease are summarized in children and adolescents. In addition, the most relevant scientific evidence about the association between NAFLD and metabolic dysregulation, focusing on clinical, pathogenetic, and histological implication will be provided with some focuses on the main treatment options.

Efficacy and Safety of Weight Reduction of the Donor in Hepatic Steatosis for Living Donor Liver Transplantation

Background

Use of steatotic livers is a known risk factor for increased primary nonfunction after liver transplantation. This study investigated the efficacy and clinical outcome of simple weight reduction of steatosis for donors undergoing living-donor liver transplantation (LDLT).

Material/Methods

We defined two groups: the reduction group, which included donors with >30% macrovesicular steatosis and body mass index (BMI) >25 kg/m², and the conventional group, which included donors with <30% macrovesicular steatosis. Donors in the reduction group were educated about the goal of voluntary weight reduction to lose 5% of body weight, not exceeding 1.6 kg/week, and attempted to maintain weight reduction for at least 8 weeks.

Results

Weight reduction significantly improved steatosis (40.71±14.56 vs. 7.867±2.67, p=0.000). Body weight and BMI were reduced in the weight reduction group (85.40±8.254 kg vs. 76.27±7.556 kg, p=0.052; and 28.89±2.303 kg/m²vs. 26.16±1.629 kg/m², p=0.025, respectively). The transplanted grafts of recipients and remnant livers of donors showed intact liver function, and there was no difference in liver function tests between the conventional and reduction groups. No significant difference in graft survival was observed.

Conclusions

Simple weight reduction improves steatosis and contributes to safer LDLT for both recipient and donor. Importantly, according to our results, even steatotic livers can be used for LDLT after patients follow a simple weight reduction protocol.

Dyslipidemia and cardiovascular disease risk among the MASHAD study population

Introduction

Dyslipidemia may be defined as increased levels of serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), or a decreased serum high-density lipoprotein cholesterol (HDL-C) concentration. Dyslipidemia is an established risk factor for cardiovascular disease (CVD). We aimed to investigate the association of dyslipidemia and CVD events among a population sample from Mashhad, in northeastern Iran.

Material and methods

This prospective cohort study comprised a population of 8698 men and women aged 35–65 years who were recruited from the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) study. Socioeconomic and demographic status, anthropometric parameters, laboratory evaluations, lifestyle factors, and medical history were gathered through a comprehensive questionnaire and laboratory and clinical assessment for all participants. Cox regression model and 95% confidence interval (CI) were used to evaluate the association of dyslipidemia and its components with CVD incidence.

Results

After 6 years of follow-up, 233 cases of CVD (including 119 cases of unstable angina [US], 74 cases of stable angina [SA], and 40 cases of myocardial infarction [MI]) were identified in the study population. Unadjusted baseline serum LDL-C, TC, and TG levels were positively associated with the risk of total CVD events among the entire population (HR: 1.54, 95% CI: 1.19–2; P-value< 0.01; HR: 1.53; 95% CI: 1.18–1.98; P < 0.01; HR: 1.57; 95% CI: 1.27–2.03; P < 0.01, respectively). However, after adjusting for confounding factors (age, body mass index [BMI], family history of CVD, smoking status [non-smoker, ex-smoker and current smoker], lipid lowering drug treatment, anti-hypertensive drug treatment, hypertension, healthy eating index [HEI], total energy intake, and presence of diabetes mellitus), a significant direct association only remained between TC and MI risk in men (HR: 2.71; 95%CI: 1.12–6.57; P-value< 0.05).

Conclusion

In the present study, TC baseline level was significantly associated with the risk of MI among men.

Prevalence of Nonalcoholic Fatty Liver Disease in Children with Obesity

OBJECTIVES

To determine the prevalence of nonalcoholic fatty liver disease (NAFLD) in children with obesity because current estimates range from 1.7% to 85%. A second objective was to evaluate the diagnostic accuracy of alanine aminotransferase (ALT) for NAFLD in children with obesity.

STUDY DESIGN

We evaluated children aged 9-17 years with obesity for the presence of NAFLD. Diseases other than NAFLD were excluded by history and laboratories. Hepatic steatosis was measured by liver magnetic resonance imaging proton density fat fraction. The diagnostic accuracy of ALT for detecting NAFLD was evaluated.

RESULTS

The study included 408 children with obesity that had a mean age of 13.2 years and mean body mass index percentile of 98.0. The study population had a mean ALT of 32 U/L and median hepatic magnetic resonance imaging proton density fat fraction of 3.7%. The estimated prevalence of NAFLD was 26.0% (95% CI 24.2%-27.7%), 29.4% in male patients (CI 26.1%-32.7%) and 22.6% in female patients (CI 16.0%-29.1%). Optimal ALT cut-point was 42 U/L (47.8% sensitivity, 93.2% specificity) for male and 30 U/L (52.1% sensitivity, 88.8% specificity) for female patients. The classification and regression tree model with sex, ALT, and insulin had 80% diagnostic accuracy for NAFLD.

CONCLUSIONS

NAFLD is common in children with obesity, but NAFLD and obesity are not concomitant. In children with obesity, NAFLD is present in nearly one-third of boys and one-fourth of girls.

Identification of genetic basis of obesity and mechanistic link of genes and lipids in Pakistani population

We aimed to identify the genetic causes of common forms of obesity in the Pakistani people and find out the mechanistic link by observing the relationship of genes and serum lipid traits. Four hundred and seventy-five subjects were genotyped for two mutations in (leptin:N103K and proopiomelanocortin:R236G) and ten common variants in different genes. Serum lipids were also measured. The prevalence of mutations was very low (one heterozygous subject each for both mutations), but fairly high minor/risk allele frequency (M/RAF) was observed for all SNPs. MAF of G2548A was 42.8% in obese and 30.1% in controls (P=5.7 × 10-5), it showed association with weight, body mass index (BMI), waist circumference (WC), high density lipoprotein cholesterol (HDL-c) and leptin, Gln223Arg had MAF 32% in obese and 18.7% in controls (P=5.4 × 10-6), it showed association with fasting plasma glucose (FPG) and all lipid traits, Ala54Thr had MAF 42.4% in obese and 33.1% (P=0.002), it showed association with none of the tested parameters. rs9939609 MAF was 26.6%, and showed association with none of the tested parameters. rs1802295 (P=0.002); rs7178572 (P=0.007); rs2028299 (P=0.04); rs4812829 (P=0.02) showed significant while rs3923113 and rs16861329 did not show a significant association (P=0.20 and P=0.3, respectively) with obesity. Major genetic contribution to common forms of obesity in Pakistan is from low/modest effect size common variants that act additively to affect body weight quantitatively and mechanism may involve modulating serum lipids.

Relationship between obesity and health-related quality of life in children aged 7-8 years

BACKGROUND

The dramatic increase in the prevalence of obesity in developed and developing countries has become a major health care concern. Accordingly, there is growing recognition of the relationship between health-related quality of life (HRQOL) and obesity in the pediatric population. This study aimed to explore the relationship between HRQOL and different indicators of obesity in children aged 7-8 years.

METHOD

In total, 182 children participated in this study (mean age 7.71 (0.29) years, 48.91% girls). To assess obesity, an InBody 230 analyzer was used to calculate body mass index (BMI) and body fat percentage (BFP). The proxy version of the KIDSCREEN-27 questionnaire was used to assess HRQOL.

RESULTS

Among boys, 17.2% were overweight and 4.3% were obese according to BMI, while in terms of body fat percentage (BFP), the corresponding percentages were 12.9 and 9.7%, respectively. Among girls, the prevalence of overweight and obesity was 11.2 and 9.0% by BMI and 10.1 and 7.9% in terms of BFP, respectively. The analysis of BFP showed a significantly higher score in normal weight boys than in obese boys in the Social Support & Peers domains (KW H-test = 10.472, p = 0.03), while in girls, there were no significant differences between weight categories and any HRQOL dimensions.

CONCLUSION

Obesity at 7-8 years of age could negatively affect some HRQOL domains; in particular, obese boys may have low social support and peer functioning.

Use of a gene score of multiple low-modest effect size variants can predict the risk of obesity better than the individual SNPs

BACKGROUND

Obesity is a complex disorder, the development of which is modulated by a multitude of environmental, behavioral and genetic factors. The common forms of obesity are polygenic in nature which means that many variants in the same or different genes act synergistically and affect the body weight quantitatively. The aim of the current study was to use information from many common variants previously identified to affect body weight to construct a gene score and observe whether it improves the associations observed. The SNPs selected were G2548A in leptin (LEP) gene, Gln223Arg in leptin receptor (LEPR) gene, Ala54Thr in fatty acid binding protein 2 (FABP2) gene, rs1121980 in fat mass and obesity associated (FTO) gene, rs3923113 in Growth Factor Receptor Bound Protein 14 (GRB14), rs16861329 in Beta-galactoside alpha-2,6-sialyltransferase 1 (ST6GAL1), rs1802295 in Vacuolar protein sorting-associated protein 26A (VPS26A), rs7178572 in high mobility group 20A (HMG20A), rs2028299 in adaptor-related protein complex 3 (AP3S2), and rs4812829 in Hepatocyte Nuclear Factor 4 Alpha (HNF4A).

METHODS

A total of 475 subjects were genotyped for the selected SNPs in different genes using different genotyping techniques. The study subjects' age, weight, height, BMI, waist and hip circumference, serum total cholesterol, triglycerides, LDL and HDL were measured. A summation term, genetic risk score (GRS), was calculated using SPSS.

RESULTS

The results showed a significantly higher mean gene score in obese cases than in non-obese controls (9.1 ± 2.26 vs 8.35 ± 2.07, p = 2 × 10- 4). Among the traits tested for association, gene score appeared to significantly affect BMI, waist circumference, and all lipid traits.

CONCLUSION

In conclusion, the use of gene score is a better way to calculate the overall genetic risk from common variants rather than individual risk variants.

Effect of dehydroepiandrosterone on the liver of perimenopausal rat: multiple doses study

Dehydroepiandrosterone (DHEA) is a widespread nutritional "anti-aging" supplement. Exogenous supplementation of DHEA is now being commonly used to augment ovarian stimulation in perimenopausal women with diminished ovarian reserve. Whether DHEA causes side effects in such age is, however, unknown. Thus, this study investigates the effects of pharmacological doses of DHEA supplementation on the liver of perimenopausal rats. DHEA supplementation to perimenopausal rats resulted in slight hepatomegaly and steatosis, hepatocytic hypertrophy, mitochondrial swelling, elevation in serum alanine aminotransaminase levels, in addition to the accumulation of lipid droplets and lipolysosomes in a dose-dependent manner. In conclusion, long-term administration of high doses of DHEA causes ultrastructural alterations and changes in the levels of cholesterol and triglyceride in hepatocytes of perimenopausal rats. DHEA at a dose of 50 mg/kg improves health and decreases the body weight, with the least side effects on the liver of perimenopausal rats.

Circulating levels of miR-122 and nonalcoholic fatty liver disease in pre-pubertal obese children

OBJECTIVES

The liver-specific miR-122 was proposed as biomarker for NAFLD in adults. Here, we investigated the relationship between miR-122 levels, parameters of liver metabolism and NAFLD in pre-pubertal obese children.

METHODS

Parameters of liver metabolism (ALT, AST and GGT) of three European cohorts were included (German cohort [n = 71; age: 11.53 ± 1.29 years; BMI z-score: 2.96 ± 0.64], Italian cohort [n = 45; age: 9.60 ± 2.11 years; BMI z-score: 3.57 ± 1.16], Slovenian cohort [n = 31; age: 7.53 ± 1.47 years; BMI z-score: 3.66 ± 0.88]). MiR-122 levels and CK18 concentrations were measured in fasting blood samples. In the German and Italian cohort, the diagnosis of NAFLD and grading of NAFLD was assessed by ultrasound.

RESULTS

NAFLD was diagnosed in n = 50 patients of the German cohort (29.6%) and in n = 29 patients (72.5%) of the Italian cohort. In all three cohorts, miR-122 was positively correlated with ALT and AST as well as with CK18 concentrations. MiR-122 levels were higher in children with NAFLD compared with healthy controls.

CONCLUSIONS

MiR-122 levels in pre-pubertal obese children could be a potential biomarker for paediatric NAFLD.

Prevalence and factors of elevated alanine aminotransferase in central Taiwan - a retrospective study

BACKGROUND

The aims of this study were to assess the prevalence of elevated alanine aminotransferase (ALT) and explore its related factors in Central Taiwan.

METHODS

The study employed a retrospective design. The study selected a sample of 5,550 subjects between the years 2000 to 2004. The indivduals undergoing health examinations in a medical center in Central Taiwan were enrolled as subjects for this research. The patients' demographics, smoking and drinking habits, laboratory findings, and abdominal ultrasound results were collected and analyzed. Correlations between variables were analyzed using SPSS/ PC Windows for frequency distribution, t-test, Chi-square test, and multivariate logistic regression.

RESULTS

There were 3103 men (55.9%) and 2447 women (44.1%). The mean age was 49.4 ± 12.3 years (age range of 20-87). The overall prevalence of elevated ALT was 17.1%, with a significant gender difference (23.2% in men vs. 9.4% in women, P < .0001). The multivariate logistic regression analysis showed that the factors significantly related to elevated ALT were central obesity, hypertriglyceridemia, and anti-HCV positive in men and women.

CONCLUSIONS

Central obesity, hypertriglyceridemia, and anti-HCV positive are factors predominantly related to elevated ALT in men and women.

Nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a disorder characterized by excess accumulation of fat in hepatocytes (nonalcoholic fatty liver (NAFL)); in up to 40% of individuals, there are additional findings of portal and lobular inflammation and hepatocyte injury (which characterize nonalcoholic steatohepatitis (NASH)). A subset of patients will develop progressive fibrosis, which can progress to cirrhosis. Hepatocellular carcinoma and cardiovascular complications are life-threatening co-morbidities of both NAFL and NASH. NAFLD is closely associated with insulin resistance; obesity and metabolic syndrome are common underlying factors. As a consequence, the prevalence of NAFLD is estimated to be 10-40% in adults worldwide, and it is the most common liver disease in children and adolescents in developed countries. Mechanistic insights into fat accumulation, subsequent hepatocyte injury, the role of the immune system and fibrosis as well as the role of the gut microbiota are unfolding. Furthermore, genetic and epigenetic factors might explain the considerable interindividual variation in disease phenotype, severity and progression. To date, no effective medical interventions exist that completely reverse the disease other than lifestyle changes, dietary alterations and, possibly, bariatric surgery. However, several strategies that target pathophysiological processes such as an oversupply of fatty acids to the liver, cell injury and inflammation are currently under investigation. Diagnosis of NAFLD can be established by imaging, but detection of the lesions of NASH still depend on the gold-standard but invasive liver biopsy. Several non-invasive strategies are being evaluated to replace or complement biopsies, especially for follow-up monitoring.

Drug disposition in obesity: toward evidence-based dosing

Obesity and morbid obesity are associated with many physiological changes affecting pharmacokinetics, such as increased blood volume, cardiac output, splanchnic blood flow, and hepatic blood flow. In obesity, drug absorption appears unaltered, although recent evidence suggests that this conclusion may be premature. Volume of distribution may vary largely, but the magnitude and direction of changes seem difficult to predict, with extrapolation on the basis of total body weight being the best approach to date. Changes in clearance may be smaller than in distribution, whereas there is growing evidence that the influence of obesity on clearance can be predicted on the basis of reported changes in the metabolic or elimination pathways involved. For obese children, we propose two methods to distinguish between developmental and obesity-related changes. Future research should focus on the characterization of physiological concepts to predict the optimal dose for each drug in the obese population.

Nonalcoholic fatty liver disease as a potential risk factor of cardiovascular disease

Nonalcoholic fatty liver disease (NAFLD) is the hepatic component of the metabolic syndrome. The aim of this review is to summarize the available data linking NAFLD with cardiovascular disease (CVD). The following topics are reviewed: (a) the clinical evidence linking NAFLD to increased prevalence of CVD; (b) the relationship between NAFLD (which is diagnosed by liver biopsy, serum liver enzymes, or ultrasonography) and incidence of CVD; (c) the mechanism linking NAFLD to CVD and clinical implication; and (d) the potential impact of NAFLD treatment on cardiac complications. CVD dictates the outcome (or outcomes) in patients with NAFLD more frequently and to a greater extent than does the progression of liver disease. NAFLD patients have a higher risk of all-cause death than the general population, mainly because of CVD or liver-related causes. The biologic mechanism linking NAFLD and CVD might be associated with various factors, involving a complex interaction among insulin resistance, oxidative stress, abnormal adipocytokine profile, endothelial dysfunction, lipid abnormalities, and activation of inflammatory cascade. Lifestyle modifications and pharmacotherapy are helpful to treat patients with NAFLD. NAFLD is likely to be associated with an increased risk of CVD, and raises the possibility that NAFLD may not only be a marker but also an early mediator of CVD.

Analysis of biochemical markers related to Fatty liver patients

[Purpose] This study was designed to study the correlation between biochemical tests and fatty liver. [Subjects and Methods] The study subjects were 242 people who received an abdominal ultrasound examination at a general hospital in Seoul, Korea, from March 2012 to March 2013. After the abdominal ultrasound examination, the subjects were categorized according to the presence or absence of fatty liver (n = 118 and 124, respectively). [Results] Comparison of biochemical markers revealed that glucose, total protein, aspartate transminase, alanine transaminase and triglyceride were higher in fatty liver patients. Risk analysis of general characteristics determined that hypertensive and diabetic patients had a 2.475- and 2.026-times greater risk of onset of fatty liver, respectively. The comparison of fatty liver with individual characteristics and biochemical markers revealed a 1.804-times greater chance of fatty liver when total protein was high, 0.964-times greater chance when high density lipoprotein was elevated and 1.204-times greater chance when triglyceride was elevated. When hypertension became severe, the chance of experiencing onset of fatty liver was 2.848 times higher. [Conclusion] Fatty liver is a representative disease of obese people in general and more active attention is necessary for its prevention and treatment. A direct cause of fatty liver was not found. Large-scale prospective studies will be required.

Metabolic syndrome, insulin resistance and Fatty liver in obese Iranian children

BACKGROUND

Obesity is a global epidemic and its morbidities such as metabolic syndrome, insulin resistance, and fatty liver leads to a spectrum of psycho-social and medical consequences.

OBJECTIVES

The objective of this study was to investigate the prevalence of fatty liver in obese Iranian children and its' association with metabolic syndrome and insulin resistance.

PATIENTS AND METHODS

102 obese Iranian children, referred to pediatric clinics from March 2011 to March 2012, were enrolled in this cross-sectional study. All the patients were visited by a pediatric endocrinologist, a pediatric gastroenterologist and an expert radiologist in the evaluation of fatty liver grading.

RESULTS

The grade of fatty liver was higher in older children (P = 0.001). It was also more in taller and heavier children (P = 0.000). The more the BMI was, the more the fatty liver grade was (P = 0.002). Severity of fatty liver according to liver sonography in patient had a positive relationship with waist circumference, hip circumference, serum TG, serum FBS, serum fasting insulin, serum ALT, systolic blood pressure and HOMA index and had a negative correlation with the level of alkaline phosphatase. Severity of fatty liver also had a close relationship with the presence of acanthosis nigricans and HOMA index.

CONCLUSIONS

Prevalence of fatty liver is high in our obese children. It was associated with criteria of metabolic syndrome and insulin resistance, so visceral fat may participate in the pathogenesis of the metabolic syndrome or merely serve as a marker of increased risk for the metabolic complications of obesity.

Paediatric gastroenterology evaluation of overweight and obese children referred from primary care for suspected non-alcoholic fatty liver disease

BACKGROUND

Screening overweight and obese children for non-alcoholic fatty liver disease (NAFLD) is recommended by paediatric and endocrinology societies. However, gastroenterology societies have called for more data before making a formal recommendation.

AIM

To determine whether the detection of suspected NAFLD in overweight and obese children through screening in primary care and referral to paediatric gastroenterology resulted in a correct diagnosis of NAFLD.

METHODS

Information generated in the clinical evaluation of 347 children identified with suspected NAFLD through screening in primary care and referral to paediatric gastroenterology was captured prospectively. Diagnostic outcomes were reported. The diagnostic performance of two times the upper limit of normal (ULN) for alanine aminotransferase (ALT) was assessed.

RESULTS

Non-alcoholic fatty liver disease was diagnosed in 55% of children identified by screening and referral. Liver disease other than NAFLD was present in 18% of those referred. Autoimmune hepatitis was the most common alternative diagnosis. Children with NAFLD had significantly (P < 0.05) higher screening ALT (98 ± 95) than children with liver disease other than NAFLD (86 ± 74). Advanced fibrosis was present in 11% of children. For the diagnosis of NAFLD, screening ALT two times the clinical ULN had a sensitivity of 57% and a specificity of 71%.

CONCLUSIONS

Screening of overweight and obese children in primary care for NAFLD with referral to paediatric gastroenterology has the potential to identify clinically relevant liver pathology. Consensus is needed on how to value the risk and rewards of screening and referral, to identify children with liver disease in the most appropriate manner.

MRI-diagnosed nonalcoholic fatty liver disease is correlated to insulin resistance in adolescents

RATIONALE AND OBJECTIVES

To evaluate the presence of nonalcoholic fatty liver disease (NAFLD) in eutrophic and obese adolescents with magnetic resonance imaging (MRI) and its relationship to insulin resistance and other potential biomarkers.

MATERIALS AND METHODS

A total of 50 adolescents (aged 11-17 years), including 24 obese and 26 eutrophic adolescents, were evaluated using MRI exams for NAFLD diagnosis. Blood analysis was performed to measure glucose, insulin, total cholesterol, high-density lipoprotein cholesterol, triglycerides, fibrinogen, aminotransferases, alkaline phosphatase, gamma-gt, and C-reactive protein. The Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index was also calculated. Laboratory test results and anthropometric assessment were statistically analyzed to determine potential correlation with NAFLD prevalence.

RESULTS

The prevalence of NAFLD among the obese was significantly higher (83.3%; CI 95: 64.5-94.5%) than that of the eutrophic group (19.2%; CI 95: 7.4-37.6%). In multivariate analysis, only HOMA-IR was an independent risk factor for diagnosis NAFLD using MRI. Compared to eutrophic adolescents, the obese adolescents had significantly higher levels for all parameters measured except for total and high-density lipoprotein cholesterol, which were significantly lower.

CONCLUSION

The prevalence of NAFLD was 19.2% among eutrophic patients and 83.3% among obese patients. Only HOMA-IR was determined to be an independent risk factor for NAFLD.

An integrated population pharmacokinetic meta-analysis of propofol in morbidly obese and nonobese adults, adolescents, and children

This study describes a population pharmacokinetic meta-analysis of propofol to characterize the influence of body size measures and age in morbidly obese and nonobese adults, adolescents, and children. Sixty morbidly obese and nonobese adult patients (55-167 kg; 21-79 years) and 34 morbidly obese and nonobese adolescents and children (37-184 kg; 9-20 years) were included. The results show that clearance increased with total body weight in an allometric function while age was found to influence clearance in a bilinear fashion with two distinct slopes, reflecting an initial increase and subsequent decrease as a result of aging. Using these two functions, the influence of both (over)weight and age on propofol clearance was well characterized, which may provide a basis for dosing across this diverse group of patients.CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e73; doi:10.1038/psp.2013.47; advance online publication 11 September 2013.

Hepatic steatosis and severity-related factors in obese children

BACKGROUND AND AIM

Obesity is an important health-care problem in developed countries. It is considered a multisystemic disease, but it may also affect the liver, thus provoking non-alcoholic fatty liver disease. This disease has been less extensively studied among children than among adults. We propose to analyze the prevalence of hepatic steatosis among a pediatric population within an area in southern Europe besides the variables associated with its development and severity.

METHODS

Cross-sectional study carried out on a population of children aged 6-14 years inclusive, using abdominal ultrasound as a method to determine the presence and severity of hepatic steatosis; in addition, anthropometric and blood-tested parameters were examined to determine which of these were associated with steatosis.

RESULTS

One hundred forty-four children were analyzed, 84 male (58.3%). Steatosis was detected in 50 children (34.7%; 95% confidence interval [CI]: 26.0-42.0%). In six of these cases (12%), elevated aminotransferase levels were recorded. Factors found to be associated with steatosis were body mass index ≥ 99th percentile (odds ratio [OR] 3.58, 95% CI 1.16-15.6) and the level of alanine aminotransferase (ALT) (OR 1.08, 95% CI 1.03-1.13), while its severity was associated with ALT (OR 1.17, 95% CI 1.09-1.28). A level of ALT < 23.5 UI/dL predicted lack of severe steatosis with an area under receiver operating characteristic curve of 0.805 (95% CI 0.683-0.927).

CONCLUSIONS

Non-alcoholic fatty liver disease is common in the obese pediatric population in our geographical area. High levels of ALT are associated with severe steatosis, although having ALT above the normal range is not common. Also, the lack of severity of steatosis can be predicted in a subgroup of children with obesity.

Prediction factors of postoperative hyperbilirubinemia in living right lobe donor: a single-center analysis of 210 cases

BACKGROUND

Hyperbilirubinemia in living liver donor is very common, but the causes are still unclear.

AIMS

We sought to clarify the risk factors and predictors of nonobstructive hyperbilirubinemia among living donors.

METHODS

We divided 210 consecutive right liver lobe donors into two groups according to the peak total bilirubin postoperatively. We collected data on preoperative, intraoperative, and postoperative biochemical measurements retrospectively, performing multivariate logistic regression analysis adjusting for potential confounders of the risk of hyperbilirubinemia.

RESULTS

There were significant differences between the two groups in donor age, body mass index, operative time, blood loss, macrovescicular steatosis, allogeneic blood transfusion rate, intensive care unit stay, hospital stay and Clavien score after donation (P < .05). Age, graft/donor weight, operative time, and blood loss were significantly associated with the risk of hyperbilirubinemia upon logistic regression analysis.

CONCLUSION

Hyperbilirubinemia, one type of hepatic dysfunction after a living donor procedure, was associated with multiple independent risk factors.

Health impact in children and adolescents

Obesity in children and adolescents is associated with multiple comorbidities, including metabolic, cardiovascular, gastrointestinal, pulmonary, orthopedic and psychological disorders. In fact, cardiovascular and metabolic impairments in childhood and adolescence constitute major risk factors for developing cardiovascular disease in adulthood. Thus, obesity in childhood and adolescence leads to a higher morbidity and mortality in adulthood. Therefore, strong emphasis must be laid on the prevention and therapy of childhood obesity. Treatment requires a multidisciplinary and multiphase approach including dietary management, physical activity, pharmacotherapy and bariatric surgery. This paper reviews the different comorbidities of childhood obesity supporting the notion of a multidisciplinary therapy concept.

[Non-alcoholic fatty liver disease in obese children and adolescents]

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in children and adolescents in industrialized countries. Recent studies have demonstrated a prevalence rate of NAFLD in overweight and obese children and adolescents in Germany of up to 30%. The spectrum of NAFLD ranges from pure fatty infiltration (simple steatosis) to inflammation (steatohepatitis, synonymous NASH) to fibrosis and cirrhosis. Age, gender, ethnicity, insulin resistance, and sex steroids are implicated in the pathogenesis of NAFLD in childhood and adolescence. Moreover, NAFLD in the pediatric age group is associated with marked cardiovascular comorbidities. This review focuses on current data regarding epidemiology, pathophysiology, comorbidities, and treatment of NAFLD in children and adolescents.

Fatty liver is a good indicator of subclinical atherosclerosis risk in obese children and adolescents regardless of liver enzyme elevation

AIM

To investigate the presence of association between nonalcoholic fatty liver disease (NAFLD) and subclinical atherosclerosis using carotid intima media thickness (c-IMT) in obese children and adolescents. Additionally, we wished to investigate the relationship between fatty liver and elevated liver enzymes.

METHODS

A total of 157 obese patients (78 boys and 79 girls, mean age: 11.3 ± 2.6 years, age range: 6-16 years) were enrolled in the study. Aminotransferase, fasting glucose and lipid levels were determined. An oral glucose tolerance test was performed. The c-IMT was measured. Infectious and metabolic causes of elevated liver enzymes were excluded. The diagnosis of NAFLD was based on ultrasound scan.

RESULTS

Obese patients with NAFLD had markedly increased carotid IMT (mean: 0.48 mm, 95% CI: 0.47-0.49) than those without NAFLD (mean: 0.45 mm 95% CI: 0.44-0.45, p < 0.001). The presence of NAFLD significantly increased c-IMT whether the patient had elevated liver enzyme or not (ANOVA, p < 0.001). In a multiple-regression model, only the presence of NAFLD was associated with increased c-IMT (β = 0.031, SE (β) = 0.008, p < 0.001).

CONCLUSION

Obese children and adolescents with NAFLD are at risk of early atherosclerotic changes. As liver function tests are not sufficient to identify patients with fatty liver, ultrasonographic evaluation of NAFLD might be considered in all obese children and adolescents.

The relationship between pediatric nonalcoholic fatty liver disease and cardiovascular risk factors and increased risk of atherosclerosis in obese children

To investigate the relationship between nonalcoholic fatty liver disease and cardiovascular risk factors and increased risk of atherosclerosis in obese children. The study included 80 consecutive obese children who were stratified into group 1 [ultrasonographically diagnosed with NAFLD (n = 50)] and group 2 [not diagnosed with NAFLD (n = 30)]. The control group included 30 healthy children. The groups were compared in terms of clinical cardiovascular risk factors and carotid intimal medial thickness (CIMT) (as a marker of atherosclerosis) measured using B-mode ultrasound. Mean body mass index (BMI) and blood pressure (BP), as well as the frequency of dyslipidemia, metabolic syndrome (MetS), and insulin resistance (IR), were similar in groups 1 and 2. Mean BMI and triglyceride (TG) levels, and the frequency of IR and MetS, increased significantly as the grade of steatosis increased. Mean CIMT in group 1 was significantly greater than that in the control group (P < 0.01). There was a positive correlation between CIMT and age, BP, and BMI in groups 1 and 2. In addition, CIMT was correlated with TG, low high-density lipoprotein (HDL) cholesterol, MetS, and IR only in group 1. Linear regression analysis between CIMT and age, BP, BMI, TG level, HDL cholesterol level, IR, MetS, and grade of steatosis yielded a significant difference only for grade of steatosis. Cardiovascular risk factors are more impressive and CIMT was significantly higher in group 1 than in group 2 and the control group, indicating that they are associated with greater risk of atherosclerosis and future adverse cardiovascular events.

Liver steatosis in Polish children assessed by medicolegal autopsies

BACKGROUND

Cases of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are increasing in the pediatric population. Their growing prevalence coincides with the obesity epidemic. Assessment of the incidence requires liver biopsies on a representative population sample, which are hampered by the absence of indications for invasive examination on children without clinical symptoms. The aim of the current study was to assess the incidence of liver steatosis in the population of children up to 18 years old from Lower Silesia.

METHODS

We retrospectively reviewed 342 medico-legal autopsy reports from 2000 to 2009. We separated a group of 256 children whose death was caused by trauma. Liver steatosis was diagnosed according to the results of histopathological examinations and typical macroscopic imaging.

RESULTS

In the 265 children who died from trauma, liver steatosis was reported in 11 (4.2%) children (6 boys) aged between 6 months and 18 years old. Six of the 11 children (54.5%) were found to be overweight. In all 342 children, steatosis was found in 18 (5.3%) children (13 boys), while NASH was diagnosed in 1 (0.3%). Excess body weight was observed in 55.6% (10/18) of children with steatosis.

CONCLUSIONS

Liver steatosis can occur at any age, even in infancy. Being overweight is a very important risk factor. Gross examination of the liver is insufficient for the diagnosis of steatosis because of its lower sensitivity and specificity. Verification of liver steatosis requires reference histopathological examination.

Evaluation of carotid artery stiffness in obese children using ultrasound radiofrequency data technology

OBJECTIVES

The goals of this study were to investigate the difference in carotid arterial stiffness in obese children compared to healthy children and to study the correlation between carotid arterial stiffness parameters and obesity using ultrasound (US) radiofrequency (RF) data technology.

METHODS

Carotid artery stiffness parameters, including the compliance coefficient, stiffness index, and pulse wave velocity, were evaluated in 71 obese patients and 47 healthy controls with US RF data technology. In addition, all participants were evaluated for fat thickness in the paraumbilical abdominal wall and fatty liver using abdominal US.

RESULTS

Compared to the control group, the blood pressure (BP), body mass index (BMI), fat thickness in the paraumbilical abdominal wall, presence of fatty liver, and carotid stiffness parameters (stiffness index and pulse wave velocity) were significantly higher in the obese group, whereas the compliance coefficient was significantly lower in the obese group. Furthermore, the pulse wave velocity was weakly positively correlated with the BMI, systolic BP, diastolic BP, and paraumbilical abdominal wall fat thickness, whereas the compliance coefficient was weakly negatively correlated with the systolic BP, BMI, and paraumbilical abdominal wall fat thickness. The presence of a fatty liver was moderately positively correlated with the BMI and weakly positively correlated with the pulse wave velocity.

CONCLUSIONS

Ultrasound RF data technology may be a sensitive noninvasive method that can be used to accurately and quantitatively detect the difference in carotid artery stiffness in obese children compared to healthy children. The detection of carotid functional abnormalities and nonalcoholic fatty liver disease in obese children should allow early therapeutic intervention, which may prevent or delay the development of atherosclerosis in adulthood.

Impact of obesity on drug metabolism and elimination in adults and children

The prevalence of obesity in adults and children is rapidly increasing across the world. Several general (patho)physiological alterations associated with obesity have been described, but the specific impact of these alterations on drug metabolism and elimination and its consequences for drug dosing remains largely unknown. In order to broaden our knowledge of this area, we have reviewed and summarized clinical studies that reported clearance values of drugs in both obese and non-obese patients. Studies were classified according to their most important metabolic or elimination pathway. This resulted in a structured review of the impact of obesity on metabolic and elimination processes, including phase I metabolism, phase II metabolism, liver blood flow, glomerular filtration and tubular processes. This literature study shows that the influence of obesity on drug metabolism and elimination greatly differs per specific metabolic or elimination pathway. Clearance of cytochrome P450 (CYP) 3A4 substrates is lower in obese as compared with non-obese patients. In contrast, clearance of drugs primarily metabolized by uridine diphosphate glucuronosyltransferase (UGT), glomerular filtration and/or tubular-mediated mechanisms, xanthine oxidase, N-acetyltransferase or CYP2E1 appears higher in obese versus non-obese patients. Additionally, in obese patients, trends indicating higher clearance values were seen for drugs metabolized via CYP1A2, CYP2C9, CYP2C19 and CYP2D6, while studies on high-extraction-ratio drugs showed somewhat inconclusive results. Very limited information is available in obese children, which prevents a direct comparison between data obtained in obese children and obese adults. Future clinical studies, especially in children, adolescents and morbidly obese individuals, are needed to extend our knowledge in this clinically important area of adult and paediatric clinical pharmacology.

Transitional features of histologic type of non-alcoholic fatty liver disease in Korean young men

BACKGROUND AND AIM

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing in Korea as the dietary pattern and lifestyle become more Westernized and the obese population increases. The spectrum of NAFLD ranges from asymptomatic steatosis to non-alcoholic steatohepatitis (NASH) and cirrhosis. Schwimmer et al. divided NASH into three types according to the histological characteristics, such as adult type, pediatric type and overlap type. We investigated clinical and histologic features of NAFLD patients in Korean young men.

METHODS

A total of 64 male patients under age 30 years, diagnosed as NAFLD by a liver biopsy, were reviewed retrospectively. NASH was diagnosed by NAFLD activity score (NAS), and NASH patients were classified with Schwimmer's histological classification.

RESULTS

Pathological features of liver biopsy revealed NASH in most cases (59 cases, 92.2%) including 29 cases (45.3%) of borderline NASH and 30 cases (46.9%) of definite NASH. The definite NASH group showed significantly high aspartate aminotransferase/alanine aminotransferase levels compared to the borderline NASH group. There were four cases (6.8%) of pediatric type, 17 cases (28.8%) of adult type, and 38 cases (64.4%) of overlap type in the NASH group. NAS was 3.75 ± 0.05 in the pediatric type, 4.29 ± 1.16 in the adult type and 4.87 ± 1.21 in the overlap type, and the overlap type showed a higher NAS than the pediatric type. The fibrosis stage was significantly higher in the overlap type than the other types.

CONCLUSION

Most Korean young men with NAFLD turned out to have borderline or definite NASH. More than half of the NASH cases showed overlap type in Korean young men.

Visceral abdominal and subfascial femoral adipose tissue have opposite associations with liver fat in overweight and obese premenopausal caucasian women

Abdominal obesity has been associated with liver fat storage. However, the relationships between other body composition depots and metabolic syndrome features with hepatic fat are still unclear. We examined abdominal and thigh adipose tissue (AT) compartments associations with liver fat in 140 overweight and obese premenopausal Caucasian women. Blood lipids and, proinflammatory and atherothrombotic markers associations with hepatic fat were also analyzed. A larger visceral AT (VAT) was related with liver fat (P < 0.05). Contrarily, thigh subfascial AT was inversely related to liver fat (P < 0.05). Increased fasting insulin, triglycerides, PAI-1 concentrations, and a higher total-cholesterol/HDL-cholesterol ratio were also associated with hepatic fat, even after adjustment for VAT (P < 0.05). Thigh subfascial adiposity was inversely associated with liver fat, suggesting a potential preventive role against ectopic fat storage in overweight and obese women. These results reinforce the contribution of an abdominal obesity phenotype associated with a diabetogenic and atherothrombotic profile to liver lipotoxicity.

Factors associated with hepatic steatosis in obese children and adolescents

OBJECTIVES

Obesity is associated with high prevalence of hepatic steatosis. We speculate that determinant factors of susceptibility to hepatic steatosis in obesity could differ between children and adolescents.

PATIENTS AND METHODS

Blood biochemical parameters, systemic oxidative stress markers, proinflammatory cytokines, and adipokine levels were determined in 157 obese children and adolescents. The subjects were divided into 2 groups: children and adolescents, identified as such in accordance with Tanner stage and the measured level of dehydroepiandrosterone sulphate. Steatosis was evaluated by ultrasonography in 127 subjects.

RESULTS

Steatosis prevalence was 44.8%. In the "children" group, those with hepatic steatosis presented higher levels of erythrocyte oxidised glutathione (GSSG) and resistin, lower levels of high-density lipoprotein (HDL) cholesterol, and lower enzymatic activities of erythrocyte glutathione reductase (GRd) and glutathione oxidase (GPx). In the "adolescents" group, those with hepatic steatosis presented higher values for body mass index z score (BMIz), insulin, peptide C, homeostatic model assessment index (HOMA-IR), alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides, GSSG, and leptin. These subjects also presented lower values for soluble leptin receptor, GRd, and GPx. In the "children" group, the only independent factor of steatosis was a decrease in GRd activity (odds ratio [OR] 0.165, 95% CI 0.03-0.84, P = 0.030). Moreover, in the "adolescent" group, the independent factors were higher for GSSG (OR 6.8, 95% CI 1.6-28.7, P = 0.010) and HOMA-IR (OR 1.9, 95% CI 1.17-3.1, P = 0.009).

CONCLUSIONS

Factors associated with hepatic steatosis differ between obese children and adolescents. Oxidative stress is seen to be the main process in children, whereas in adolescents oxidative stress and insulin resistance are significant factors for steatosis.

Pediatric nonalcoholic fatty liver disease, metabolic syndrome and cardiovascular risk

Nonalcoholic fatty liver disease (NAFLD) encompasses a range of liver histology severity and outcomes in the absence of chronic alcohol use. The mildest form is simple steatosis in which triglycerides accumulate within hepatocytes. A more advanced form of NAFLD, non-alcoholic steatohepatitis, includes inflammation and liver cell injury, progressive to cryptogenic cirrhosis. NAFLD has become the most common cause of chronic liver disease in children and adolescents. The recent rise in the prevalence rates of overweight and obesity likely explains the NAFLD epidemic worldwide. NAFLD is strongly associated with abdominal obesity, type 2 diabetes, and dyslipidemia, and most patients have evidence of insulin resistance. Thus, NAFLD shares many features of the metabolic syndrome (MetS), a highly atherogenic condition, and this has stimulated interest in the possible role of NAFLD in the development of atherosclerosis. Accumulating evidence suggests that NAFLD is associated with a significantly greater overall mortality than in the general population, as well as with increased prevalence of cardiovascular disease (CVD), independently of classical atherosclerotic risk factors. Yet, several studies including the pediatric population have reported independent associations between NAFLD and impaired flow-mediated vasodilatation and increased carotid artery intimal medial thickness-two reliable markers of subclinical atherosclerosis-after adjusting for cardiovascular risk factors and MetS. Therefore, the rising prevalence of obesity-related MetS and NAFLD in childhood may lead to a parallel increase in adverse cardiovascular outcomes. In children, the cardiovascular system remains plastic and damage-reversible if early and appropriate interventions are established effectively. Therapeutic goals for NAFLD should address nutrition, physical activity, and avoidance of smoking to prevent not only end-stage liver disease but also CVD.

Intrahepatic and intramyocellular lipids are determinants of insulin resistance in prepubertal children

AIMS/HYPOTHESIS

We hypothesised that ectopic fat deposition is present in liver and skeletal muscle before puberty and that both are potentially important factors in the early pathogenesis of insulin resistance.

METHODS

Proton magnetic resonance spectroscopy was used to evaluate intramyocellular and intrahepatic lipids in 50 male and 42 female multi-ethnic, prepubertal (Tanner < 2) children (8.1 ± 0.8 years; 35.4 ± 10.7 kg; 27.9 ± 8.3% body fat; means ± SD). Intramyocellular lipid was measured in soleus muscle and intrahepatic lipid in the middle right lobe. Abdominal fat was measured by magnetic resonance imaging, body fat by dual energy X-ray absorptiometry, and insulin resistance using homeostatic model assessment.

RESULTS

Intrahepatic lipid ranged from 0.11% to 4.6% relative to the liver water signal (mean 0.79 ± 0.79%) whereas intramyocellular lipid ranged from 0.13% to 1.86% relative to the muscle water signal (mean 0.51 ± 0.28%). Intramyocellular and intrahepatic lipids were significantly correlated with total adiposity (r = 0.49 and 0.59), abdominal adiposity (r = 0.44 and 0.54), and each other (r = 0.39, p < 0.05, Spearman). Both intramyocellular and intrahepatic lipid were positively correlated with fasting insulin (r = 0.37 and 0.38 respectively) and insulin resistance (r = 0.37 and 0.37; p < 0.01). After adjustment for race and sex, the relations between ectopic fat and insulin resistance remained, whereas both disappeared when further adjusted for body fat or BMI z scores.

CONCLUSIONS/INTERPRETATIONS

These results suggest that typical relations between body composition, ectopic fat and insulin resistance are present in children before puberty. Thus, interventions aimed at reducing adiposity have the potential to decrease ectopic fat accumulation, delay the onset of insulin resistance and decrease the risk for development of type 2 diabetes in children.

Iron load and liver enzymes in 10- and 13-year-olds

OBJECTIVES

Iron plays a pivotal role in adult steatosis, but its role in child and adolescent steatosis is unclear. We investigated the effect of dietary iron, serum iron, and ferritin on serum transaminases and γ-glutamyltransferase in 10- and 13-year-olds.

PATIENTS AND METHODS

The study included 4894 fifth and eighth graders enrolled between 2006 and 2009 in all schools in Shunan City, Japan. Multiple regression analyses were performed with adjustments for grade, sex, z score of the body mass index, serum lipids, plasma glucose, frequency of sports activities, having a single parent, number of siblings, tobacco smoking behavior, passive smoking at home, resident areas, and schools, using linear mixed models. In addition, we analyzed ferritin and insulin resistance in randomly selected subset of participants.

RESULTS

Dietary iron intake was positively associated with serum alanine aminotransferase levels (standardized coefficient β = 2.35, P = 0.019). Serum iron concentrations were associated with transaminase and γ-glutamyltransferase levels (β = 3.22, and 4.05, respectively, P < 0.01). In the subset of 421 subjects with further serum analysis, serum ferritin levels were significantly associated with serum enzyme levels (β = 2.43-3.35; P < 0.05) and showed significant odds ratio for the elevated alanine aminotransferase levels (1.05 for 1 SD with 95% confidence intervals 1.02-1.08). However, iron load did not show a positive association with insulin resistance.

CONCLUSIONS

Although an effect size for iron is small in regression analyses, iron is implicated in increased transaminase levels in prepubertal and pubertal children.

Pediatric nonalcoholic fatty liver disease: Overview with emphasis on histology

Nonalcoholic fatty liver disease (NAFLD) is a disease in which excessive fat accumulates in the liver of a patient without a history of alcohol abuse. This disease includes simple steatosis and nonalcoholic steatohepatitis (NASH). NAFLD/NASH is recognized as a hepatic manifestation of metabolic syndrome. In recent years, pediatric NAFLD has increased in line with the increased prevalence of pediatric obesity. The estimated prevalence of pediatric NAFLD is 2.6%-9.6%, and it is associated with sex, age, and ethnicity. With regard to the pathogenesis of NAFLD, the “two-hit” hypothesis is widely accepted and oxidative stress is thought to play an important role in the second hit. Although clinical symptoms, laboratory data, and imaging findings are important, liver biopsy is regarded as the gold standard for the diagnosis of NAFLD/NASH. In addition, liver biopsy is essential for assessing the degree of necro-inflammatory change and fibrosis in NASH. Two different types of steatohepatitis (type 1 and type 2 NASH) have been reported, with type 2 NASH being present in as many as 51% of pediatric NAFLD patients. However, we and others have observed that type 1 and 2 patterns commonly overlap. Although pharmacotherapy has been studied in clinical trials, lifestyle modification by diet and exercise remains the mainstay of treatment for NAFLD/NASH.