Pediatric nonalcoholic fatty liver disease in 2009

The impact of metabolic disorders on management of periodontal health in children

Periodontitis is a chronic inflammatory disease caused by plaque biofilm which shares risk factors with systemic chronic diseases such as diabetes, cardiovascular disease, and osteoporosis. Many studies have found increased prevalence and rate of progression of periodontal disease in children with common metabolic disorders. Although the causal relationship and specific mechanism between them has not been determined yet. The aim of this paper is to progress on the impact of metabolic disorders on periodontal health in children and the underlying mechanisms, which provides new evidences for the prevention and intervention of metabolic disorders and periodontitis in children.

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.

Development of Thyroid Hormones and Synthetic Thyromimetics in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is the fastest-growing liver disease in the world. Despite targeted agents which are needed to provide permanent benefits for patients with NAFLD, no drugs have been approved to treat NASH. Thyroid hormone is an important signaling molecule to maintain normal metabolism, and in vivo and vitro studies have shown that regulation of the 3,5,3'-triiodothyronine (T3)/ thyroid hormone receptor (TR) axis is beneficial not only for metabolic symptoms but also for the improvement of NAFLD and even for the repair of liver injury. However, the non-selective regulation of T3 to TR subtypes (TRα/TRβ) could cause unacceptable side effects represented by cardiotoxicity. To avoid deleterious effects, TRβ-selective thyromimetics were developed for NASH studies in recent decades. Herein, we will review the development of thyroid hormones and synthetic thyromimetics based on TR selectivity for NAFLD, and analyze the role of TR-targeted drugs for the treatment of NAFLD in the future.

Association Between Non-invasive Diagnostic Methods of Liver Fibrosis and Type 2 Diabetes in Pediatric Patients With Non-alcoholic Fatty Liver Disease

BACKGROUND AND PURPOSE

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children has been increasing associated with insulin resistance. However, there is a scarcity of related studies in children with NAFLD with type 2 diabetes mellitus (T2DM) compared to adults. We conducted this study to investigate the association between non-invasive diagnostic methods of liver fibrosis and T2DM in pediatric patients with NAFLD.

METHODS

We enrolled a total of 152 patients aged <18 years with NAFLD, and compared their data according to the presence of T2DM. We evaluated fibrosis by transient elastography (TE, FibroScan®), and calculated the following fibrosis scores for each patient: NAFLD fibrosis score (NFS), AST: platelet ratio index (APRI), Fibrosis-4 (FIB-4) index, and pediatric NAFLD fibrosis index (PNFI).

RESULTS

In the NAFLD-T2DM group, the NFS and mean controlled attenuation parameter in FibroScan were significantly higher than those in the nondiabetic group. The receiver operating characteristic (ROC) curve values for predicting the presence of T2DM were 0.78 for NFS, 0.64 for FIB-4, 0.62 for PNFI, and 0.61 for APRI. The cutoff HbA1c levels for predicting fibrosis progression in APRI, NFS, and PNFI were 5.7% [area under the curve (AUC) 0.74], 6.4% (AUC 0.71), and 6.4% (AUC 0.55), respectively. In the multivariate analysis, hepatosteatosis on abdomen sonography, NFS, FibroScan F, and APRI were independently associated with T2DM risk.

CONCLUSIONS

We significantly characterized non-invasive fibrosis markers and elastography in pediatric NAFLD with T2DM compared with the nondiabetic group. We suggest evaluating the progression of fibrosis in the prediabetic stage in children using a combination of these non-invasive methods.

Distinctive Features of Hepatic Steatosis in Children: Is It Primary or Secondary to Inborn Errors of Metabolism?

PURPOSE

The incidence of hepatic steatosis among children has been increasing; however, data distinguishing simple steatosis from a more complex disorder are lacking.

METHODS

This study identified the etiologies resulting in hepatic steatosis through a retrospective review of pediatric liver biopsies performed in the last 10 years. A total of 158 patients with hepatic steatosis proven by histopathological evaluation were enrolled in the study, and baseline demographic features, anthropometric measurements, physical examination findings, laboratory data, ultrasonographic findings, and liver histopathologies were noted.

RESULTS

The two most common diagnoses were inborn errors of metabolism (IEM) (52.5%) and nonalcoholic fatty liver disease/steatohepatitis (NAFLD/NASH) (29.7%). The three most common diseases in the IEM group were glycogen storage disorders, Wilson's disease, and mitochondrial disease. The rates of consanguineous marriage (75.6%; odds ratio [OR], 26.040) and positive family history (26.5%; OR, 8.115) were significantly higher (p=0.002, p<0.001, respectively) in the IEM group than those in the NAFLD/NASH group. Younger age (p=0.001), normal anthropometric measurements (p=0.03), increased aspartate aminotransferase levels (p<0.001), triglyceride levels (p=0.001), and cholestatic biochemical parameters with disrupted liver function tests, as well as severe liver destruction of hepatic architecture, cholestasis, fibrosis, and nodule formation, were also common in the IEM group.

CONCLUSION

Parents with consanguinity and positive family history, together with clinical and biochemical findings, may provide a high index of suspicion for IEM to distinguish primary steatosis from the consequence of a more complex disorder.

Changes in Liver Enzymes and Metabolic Profile in Adolescents with Fatty Liver following Exercise Interventions

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is the most frequent cause of chronic liver diseases in both adults and children with obesity. The aim of this study was to compare the changes in liver enzymes and metabolic profile in adolescents with fatty liver following selected school-based exercise (SBE) and high-intensity interval training (HIIT) interventions.

METHODS

In a semi-experimental study, 34 obese male adolescents with clinically defined NAFLD were divided into the HIIT (n=11, age=12.81±1.02 years, body mass index [BMI]=26.68 ±2.32 kg/m²), selected SBE (n=11, age=13.39±0.95 years, BMI=26.47±1.74 kg/m²), and control (n=12, age=13.14±1.49 years, BMI=26.45±2.21 kg/m²) groups. The ultrasonography NAFLD grade, peak oxygen uptake (VO_2peak), lipid profile, insulin resistance, and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of the participants were measured before and after the exercise interventions.

RESULTS

The BMI, waist-to-hip ratio, and body fat percentage of the participants decreased, and a significant increase in VO_2peak was observed after the intervention; however, the HIIT group showed a significant improvement compared with the SBE group (p<0.01). Significant reductions were observed in the levels of insulin resistance, triglyceride, total cholesterol, ALT, and AST in both groups, although high-density lipoprotein levels decreased only in the HIIT group (p<0.01). Further, a significant reduction in low-density lipoprotein level was observed in the training groups (p<0.01), but this decrease was not significant compared with the control group (p>0.01).

CONCLUSION

HIIT and SBE are equally effective in improving health parameters in obese children and adolescents.

Effects of a carbohydrate-restricted diet on hepatic lipid content in adolescents with non-alcoholic fatty liver disease: A pilot, randomized trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has emerged as the most common form of liver disease among adolescents in industrialized countries. While lifestyle intervention remains the hallmark treatment for NAFLD, the most effective dietary strategy to reverse NAFLD in children is unknown.

OBJECTIVE

The objective of this study was to determine the effects of a moderately CHO-restricted diet (CRD) vs fat-restricted diet (FRD) in adolescents with NAFLD on reduction in liver fat and insulin resistance.

METHODS

Thirty-two children/adolescents (age 9-17) with obesity and NAFLD were randomized to a CRD (<25:25:>50% energy from CHO:protein:fat) or FRD (55:25:20) for 8 weeks. Caloric intakes were calculated to be weight maintaining. Change in hepatic lipid content was measured via magnetic resonance imaging, body composition via dual energy X ray absorptiometry and insulin resistance via a fasting blood sample.

RESULTS

Change in hepatic lipid did not differ with diet, but declined significantly (-6.0 ± 4.7%, P < .001 only within the CRD group. We found significantly greater decreases in insulin resistance (HOMA-IR, <.05), abdominal fat mass (P < .01) and body fat mass (P < .01) in response to the CRD vs FRD.

CONCLUSION

These findings suggest that consumption of a moderately CHO-restricted diet may result in decreased hepatic lipid as well as improvements in body composition and insulin resistance in adolescents with NAFLD even in the absence of intentional caloric restriction. Larger studies are needed to determine whether a CHO-restricted diet induces change in hepatic lipid independent of change in body fat.

The offspring from rats fed a fatty diet display impairments in the activation of liver peroxisome proliferator activated receptor alpha and features of fatty liver disease

Maternal obesity programs liver derangements similar to those of NAFLD. Our main goal was to evaluate whether these liver anomalies were related to aberrant PPARα function. Obesity was induced in female Albino-Wistar rats by a fatty diet (FD rats). Several parameters related to NAFLD were evaluated in both plasma and livers from fetuses of 21 days of gestation and 140-day-old offspring. FD fetuses and offspring developed increased levels of AST and ALT, signs of inflammation and oxidative and nitrative stress-related damage. FD offspring showed dysregulation of Plin2, CD36, Cyp4A, Aco, Cpt-1, Hadha and Acaa2 mRNA levels, genes involved in lipid metabolism and no catabolic effect of the PPARα agonist clofibrate. These results suggest that the FD offspring is prone to develop fatty liver, a susceptibility that can be linked to PPARα dysfunction, and that this could in turn be related to the liver impairments programmed by maternal obesity.

A Nomogram for Predicting Non-Alcoholic Fatty Liver Disease in Obese Children

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) ranges in severity from simple steatosis to steatohepatitis. Early detection of NAFLD is important for preventing the disease from progressing to become an irreversible end-stage liver disease. We developed a nomogram that allows for non-invasive screening for NAFLD in obese children.

METHODS

Anthropometric and laboratory data of 180 patients from our pediatric obesity clinic were collected. Diagnoses of NAFLD were based on abdominal ultrasonographic findings. The nomogram was constructed using predictors from a multivariate analysis of NAFLD risk factors.

RESULTS

The subjects were divided into non-NAFLD (n=67) and NAFLD groups (n=113). Factors, including sex, body mass index, abdominal circumference, blood pressure, insulin resistance, and levels of aspartate aminotransferase, alanine aminotransferase (ALT), γ-glutamyl transpeptidase (γGT), uric acid, triglycerides, and insulin, were significantly different between the two groups (all p<0.05) as determined using homeostatis model assessment of insulin resistance (HOMA-IR). In our multivariate logistic regression analysis, elevated serum ALT, γGT, and triglyceride levels were significantly related to NAFLD development. The nomogram was established using γGT, uric acid, triglycerides, HOMA-IR, and ALT as predictors of NAFLD probability.

CONCLUSION

The newly developed nomogram may help predict NAFLD risk in obese children. The nomogram may also allow for early NAFLD diagnosis without the need for invasive liver biopsy or expensive liver imaging, and may also allow clinicians to intervene early to prevent the progression of NAFLD to become a more advanced liver disease.

Revision of serum ALT upper limits of normal facilitates assessment of mild liver injury in obese children with non-alcoholic fatty liver disease

Background

The serum alanine aminotransferase (ALT) level is a critical parameter for evaluating liver injury in non‐alcoholic fatty liver disease (NAFLD). However, the currently accepted upper limits of normal (ULN) for serum ALT (ULN‐ALT) are debated, as they may be excessively high.

Methods

A total of 1638 children aged 6‐16 years, comprising 507 children with normal BMI (500 healthy children and 7 children with NAFLD), 199 overweight children, and 932 obese children, were included in the analysis. We re‐evaluated the ULN‐ALT in 500 healthy Chinese children using the 95th percentiles of serum ALT levels as revised ULN‐ALT. Fatty liver was identified by ultrasound examination.

Results

Significant positive correlations between serum ALT levels and body mass index (BMI) were detected in overweight boys (r = .399, P < .001), obese boys (r = .398, P < .001), and obese girls (r = .392, P < .001). The prevalence percentages of NAFLD were 93.6%, 75.8%, and 37.9% in obese boys with serum ALT levels of >50, 25‐50, and ≤25 U/L and were 81.6%, 67.9%, and 20.6% in obese girls with serum ALT levels of >40, 20‐40, and ≤20 U/L, respectively.

Conclusion

Serum ALT levels significantly correlated with abnormal BMI values in children, suggesting a rigorous BMI threshold is needed to establish the cutoffs for serum ULN‐ALT in children. Besides, the revised serum ULN‐ALT can uncover mild liver injury in obese children with NAFLD.

Prevalence of prediabetes and type 2 diabetes in children with obesity and increased transaminases in European German-speaking countries. Analysis of the APV initiative

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), prediabetes and type 2 diabetes mellitus are known to be closely linked with obesity as early as during childhood.

OBJECTIVES

The study aimed to determine the prevalence of prediabetes and T2DM in children with obesity with or without increased transaminases.

METHODS

Data from the observational multicentre (n = 51), cross-sectional Adipositas Patienten Verlaufsbeobachtung registry were analyzed. Mild increase (mild group) was defined by alanine transaminase (ALT) >24 to ≤50 U/L and moderate to severe increase (advanced group) by ALT > 50 U/L. Prediabetes and T2DM were defined according to recent IDF/ISPAD guidelines.

RESULTS

The prevalence of prediabetes and T2DM was 11.9% (95% CI: 11.0-12.8) and 1.4% (95% CI: 1.1-1.7) among all participants (n = 4932; male = 2481; mean age 12.9 ± 2.7 years; BMI-SDS 2.1 ± 0.5; Tanner stage 3.2 ± 1.5). The prevalence of impaired glucose metabolism (prediabetes and T2DM) was 13.8% (95% CI: 12.1-15.4) in the mild, 21.9% (95% CI: 18.8-25.1) in the advanced group, 10.7% (95% CI: 9.4-11.9) in the control group. Mild and advanced groups had greater odds ratios for prediabetes [1.42; 95% CI: 1.17-1.72, 2.26-fold; (1.78-2.86), respectively], the advanced group also for T2DM [2.39 (1.36-4.21)] compared to controls. While an increase in transaminases predominantly affected boys, girls within the advanced group had a higher T2DM prevalence than males (5.4 vs. male 2.1%).

CONCLUSIONS

Children with obesity and increased liver transaminases as surrogates of NAFLD should be screened for T2DM.

The relationship between vitamin D level and hepatosteatosis in obese children

OBJECTIVE:

The increasing incidence of obesity in children is a significant risk factor for nonalcoholic fatty liver disease and obesity-associated morbidity. In the present study, we aimed to explore the correlation between Vitamin D level and hepatosteatosis in obese children.

METHODS:

A total of 110 children aged 10–16 years who presented to pediatric endocrinology outpatient clinic for obesity were enrolled. The study was completed in a single season between September and November. Hepatosteatosis was diagnosed by ultrasonography. The patients were grouped into two groups: Group 1 comprised patients with hepatosteatosis and Group 2 consisted of patients without hepatosteatosis. 25 hydroxy (25-OH) Vitamin D levels were compared between patients with and without hepatosteatosis.

RESULTS:

No statistically significant difference was observed between 25-OH Vitamin D levels of patients with and without hepatosteatosis. When the effects of age and sex were kept constant, there was no significant correlation between Vitamin D level and aspartate aminotransferase, alanine aminotransferase, and body mass index values.

CONCLUSION:

Unlike the results of the previous studies, we were unable to detect any significant difference between Vitamin D levels of obese patients with and without hepatosteatosis. We think that obesity, rather than Vitamin D status, that is, in fact, independently associated with nonalcoholic fatty liver disease. Larger studies are needed to investigate the impact of Vitamin D in children with obesity with hepatosteatosis.

Dietary determinants of hepatic fat content and insulin resistance in overweight/obese children: a cross-sectional analysis of the Prevention of Diabetes in Kids (PREDIKID) study

Paediatric non-alcoholic fatty liver disease has increased in parallel with childhood obesity. Dietary habits, particularly products rich in sugars, may influence both hepatic fat and insulin resistance (homeostatic model assessment for insulin resistance (HOMA-IR)). The aim of the study was to examine the association of the consumption of foods and food components, dairy desserts and substitutes (DDS), sugar-sweetened beverages (SSB), as well as total and added sugars, with hepatic fat and HOMA-IR. Dietary intake (two non-consecutive 24 h-recalls), hepatic fat (MRI) and HOMA-IR were assessed in 110 overweight/obese children (10·6 (sd 1·1) years old). Linear regression analyses were used to examine the association of dietary intake with hepatic fat and HOMA-IR adjusted for potential confounders (sex, age, energy intake, maternal educational level, total and abdominal adiposity and sugar intake). The results showed that there was a negative association between cereal intake and hepatic fat (β=-0·197, P&lt;0·05). In contrast, both SSB consumption (β=0·217; P=0·028) and sugar in SSB (β=0·210, P=0·035), but not DDS or sugar in DDS or other dietary components, were positively associated with hepatic fat regardless of potential confounders including total sugar intake. In conclusion, cereal intake might decrease hepatic fat, whereas SSB consumption and its sugar content may increase the likelihood of having hepatic steatosis. Although these observations need to be confirmed using experimental evidence, these results suggest that healthy lifestyle intervention programs are needed to improve dietary habits as well as to increase the awareness of the detrimental effects of SSB consumption early in life.

Psychosocial Issues in Pediatric Nonalcoholic Fatty Liver Disease

BACKGROUND

In recent years, the adoption of unhealthy dietary habits and a sedentary lifestyle has led to an alarming increase in the prevalence of non-alcoholic fatty liver disease (NAFLD) in pediatric populations. Hepatic steatosis is now considered the most common cause of chronic liver disease in children and adolescents and may progress to liver fibrosis and even cirrhosis, increasing long-term mortality rates. Apart from its severe medical co-morbidities, pediatric NAFLD is associated with a variety of psychosocial factors which act either as precipitants or consequences of the disease.

OBJECTIVE

Studying these parameters might expand our understanding of NAFLD pathogenesis and provide a framework for more effective management.

METHOD

In this context, we performed a literature review focusing on the associations of pediatric NAFLD with psychosocial parameters to detect and integrate the most recent data on this topic and provide a scaffold for further conceptualization and research.

RESULTS

There are a limited number of studies addressing issues of psychosocial functioning in children with NAFLD. Pediatric NAFLD is frequently accompanied by neuropsychiatric symptoms and poor quality of life and the level of impairment does not correlate with the degree of hepatic damage. In addition, mentally and intellectually-impaired youth appear at greater risk for developing liver steatosis.

CONCLUSIONS

Pediatric NAFLD is associated with psychosocial parameters in a bidirectional way. Further research is needed on NAFLD's psychosocial correlates and on the effect of treatment on patients' well-being.

In a pilot study, reduced fatty acid desaturase 1 function was associated with nonalcoholic fatty liver disease and response to treatment in children

BACKGROUND

FADS1 gene encodes delta 5 desaturase, a rate-limiting enzyme in the metabolism of n-3 and n-6 polyunsaturated fatty acids (PUFAs). Minor alleles of FADS1 locus polymorphisms are associated with reduced FADS1 expression and intra-hepatic fat accumulation. However, the relationship between FADS1 expression and pediatric nonalcoholic fatty liver disease (NAFLD) risk remains to be explored.

METHODS

We analyzed FADS1 transcription levels and their association with intra-hepatic fat and histology in children, and we performed pathway enrichment analysis on transcriptomic profiles associated with FADS1 polymorphisms. We also evaluated the weight of FADS1 alleles on the response to combined docosahexaenoic acid, choline, and vitamin E (DHA-CHO-VE) treatment.

RESULTS

FADS1 mRNA level was significantly and inversely associated with intra-hepatic fat (p = 0.004), degree of steatosis (p = 0.03), fibrosis (p = 0.05), and NASH (p = 0.008) among pediatric livers. Transcriptomics demonstrated a significant enrichment of a number of pathways strongly related to NAFLD (e.g., liver damage, fibrosis, and hepatic stellate cell activation). Compared to children who are common allele homozygotes, children with FADS1 minor alleles had a greater reduction in steatosis, fibrosis, and NAFLD activity score after DHA-CHO-VE.

CONCLUSION

This study suggests that decreased FADS1 expression may be associated with NAFLD in children but an increased response to DHA-CHO-VE.

Macrophage Markers Are Poorly Associated With Liver Histology in Children With Nonalcoholic Fatty Liver Disease

OBJECTIVES

We have previously demonstrated associations between the macrophage activation marker soluble (s)CD163 and histology of nonalcoholic fatty liver disease (NAFLD) in adults, and elevated sCD163 levels in children with obesity with NAFLD. Macrophage activation has, however, not been investigated in children with biopsy-proven NAFLD, which was the objective of the present study.

METHODS

We used in-house enzyme-linked immunosorbent assays to measure sCD163 and the novel macrophage marker soluble mannose receptor (sMR) in a cross-sectional (n = 155) pediatric NAFLD cohort, and a cohort of NAFLD children (n = 36) undergoing a randomized trial by the probiotic VSL#3. We included 56 healthy nonobese children for comparison.

RESULTS

Levels of sCD163 and sMR were higher in both of the NAFLD cohorts compared with controls (P < 0.001). In the cross-sectional cohort, sCD163 only showed trends toward association with ballooning (rho = 0.14, P = 0.08) and portal inflammation (rho = 0.17, P = 0.08). sMR showed similar associations with liver histology. In the VSL#3 cohort, sCD163 correlated inversely with steatosis (rho = -0.35, P = 0.04), and lobular (rho = -0.57, P < 0.001) and portal inflammation (rho = -0.38, P = 0.02); sMR was not associated with any histological scores. Neither sCD163 nor sMR changed significantly during intervention, and without association with NAFLD resolution.

CONCLUSIONS

The macrophage activation markers sCD163 and sMR showed poor associations with liver histology in 2 different cohorts of children with biopsy-proven NAFLD, and none of the markers decreased during successful intervention. These results are in contrast with studies of adult NAFLD and may suggest a possibility of different roles for macrophages in the pathogenesis of adult and pediatric NAFLD.

Nonalcoholic fatty liver disease with prolactin-secreting pituitary adenoma in an adolescent: A case report

RATIONALE

Nonalcoholic fatty liver disease (NAFLD), among the commonest chronic liver disorders in children and adolescents, is considered a reflection of the current obesity epidemic in children and adults. This liver disease has been linked with various metabolic disorders, but not with prolactinoma (PRLoma).

PATIENT CONCERNS

A 13-year-old Japanese girl manifested obesity, serum transaminase and γ-glutamyltransferase elevations, and amenorrhea. Abdominal ultrasonography showed fatty liver. Her serum prolactin concentration was elevated, and cranial magnetic resonance imaging showed a pituitary mass consistent with macroadenoma.

DIAGNOSES

NAFLD and PRLoma.

INTERVENTIONS AND OUTCOMES

After the patient's NAFLD failed to respond to diet and exercise, cabergoline treatment of the PRLoma decreased body weight, serum transaminase and γ-glutamyltransferase elevations, and ultrasonographic fatty liver grade as the tumor became smaller.

LESSONS

Physicians should consider the possibility of PRLoma when diet and exercise fail to improve fatty liver disease in a patient with endocrine symptoms such as amenorrhea.

Activated carbon N-acetylcysteine microcapsule protects against nonalcoholic fatty liver disease in young rats via activating telomerase and inhibiting apoptosis

Non-alcoholic fatty liver disease (NAFLD) is becoming one of the world's most common chronic liver diseases in childhood, yet no therapy is available that has been approved by the food and drug administration (FDA). Previous studies have reported that telomere and telomerase are involved the development and progression of NAFLD. This study was designed to investigate the potential beneficial effects of activated carbon N-acetylcysteine (ACNAC) microcapsules on the development of NAFLD in young rats as well as the underlying mechanism(s) involved. Three-week old male Sprague Dawley rats were given high-fat diet (HFD) with/without ACNAC treatment for 7 consecutive weeks. Liver pathologies were determined by hematoxylin and eosin (H&E) and Oil Red O staining, as well as by changes in biochemical parameters of plasma alanine transaminase (ALT) and aspartate transaminase (AST) levels, respectively. Glucose homeostasis was evaluated by the glucose tolerance test and the liver telomere length and activity were measured by real time PCR and telomeric repeat amplification protocol (TRAP). Western blot analysis was performed to determine the expression level of Bcl-2, Bax and Caspase-3. Our results demonstrated that ACNAC supplementation improved liver pathologies of rats that received long-term HFD feeding. ACNAC supplementation prevented HFD-induced telomere shortening and improved telomerase activity. Moreover, in comparison to HFD-fed rats, ACNAC supplementation markedly increased the expression of Bcl-2, but significantly decreased the expression of Bax and Caspase-3 in juvenile rats. Together, these results indicate that ACNAC may be a promising choice for preventing and treating NAFLD among children.

Assessment of Fatty Liver in Models of Disease Programming

Nonalcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease worldwide and is present in a third of the general population and the majority of individuals with obesity and type 2 diabetes. Importantly, NAFLD can progress to severe nonalcoholic steatohepatitis (NASH), associated with liver failure and hepatocellular carcinoma. Recent research efforts have extensively focused on identifying factors contributing to the additional "hit" required to promote NALFD disease progression. The maternal diet, and in particular a high-fat diet (HFD), may be one such hit "priming" the development of severe fatty liver disease, a notion supported by the increasing incidence of NAFLD among children and adolescents in Westernized countries. In recent years, a plethora of key studies have used murine models of maternal obesity to identify fundamental mechanisms such as lipogenesis, mitochondrial function, inflammation, and fibrosis that may underlie the developmental priming of NAFLD. In this chapter, we will address key considerations for constructing experimental models and both conventional and advanced methods of quantifying NAFLD disease status.

Girls and Boys Have a Different Cardiometabolic Response to Obesity Treatment

Background: Childhood obesity exposes individuals to cardiometabolic disturbances. We analyzed how family-based multidisciplinary obesity treatment influenced children's cardiometabolic health. Materials and methods: In this retrospective, two-year, follow-up study of 654 2- to 18-year-old children treated for obesity in three Finnish pediatric clinics in 2005-2012, blood pressure (BP), metabolic parameters, and the influence of sex, puberty and a change in body mass index standard deviation score (BMI SDS) were analyzed. Results: At baseline, at least one cardiovascular risk factor was present in 474 (80%) cases. Boys presented with more significant changes in cardiometabolic parameters than girls during the treatment. Boys' total cholesterol (TC) improved by 12 months (P = 0.009), and their low-density lipoprotein C (LDL-C) and glycosylated hemoglobin ameliorated by 12 months (P = 0.030 and 0.022, respectively) and 24 months (P = 0.043 and 0.025, respectively). Boys' triglycerides, insulin, homeostasis model assessment for insulin resistance (HOMA-IR) and systolic BP deteriorated at 24 months (P < 0.001, 0.004, 0.002, and 0.037, respectively). In all children, the number of acceptable TC, LDL-C, insulin, and HOMA-IR values increased if BMI SDS reduced 0.25 or more by 12 months. Conclusion: Minor cardiometabolic improvements were found during the obesity treatment. These findings indicate the need to assess treatment methods and focus on prevention.

The effect of diet or exercise on ectopic adiposity in children and adolescents with obesity: a systematic review and meta-analysis

OBJECTIVE

Ectopic fat depostion in youth with obesity is associated with an increased cardiovascular disease risk. The aim of this meta-analysis was to summarize the evidence for the use of diet and/or exercise on ectopic adiposity in this population.

METHODS

A systematic literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement. Clinical trials that assessed ectopic fat deposition and included study arms with diet and/or exercise were searched in PubMed, PEDro and the Cochrane database.

RESULTS

Hepatic fat content and intramyocellular lipid content were described in nine studies and three studies, respectively. Most studies included teenagers, and study duration ranged between 3 and 12 months without follow-up. Using random-effects weights, the standardized mean difference of the change in hepatic adiposity (totalling 320 subjects) was -0.54 Hedges' g (95% confidence interval: -0.69 to -0.38 with p < 0.0001). By re-expressing this effect size, it is seen that diet and/or exercise results in an absolute reduction of intrahepatic lipid with 2%, which accords with a relative reduction up to 70%. Although there were significant ameliorations of insulin sensitivity, no significant changes in intramyocellular lipid were observed.

CONCLUSIONS

This meta-analysis showed that diet and/or exercise is effective to reduce hepatic adiposity in youth with obesity.

Association of MTTP gene variants with pediatric NAFLD: A candidate-gene-based analysis of single nucleotide variations in obese children

Objective

We used targeted next-generation sequencing to investigate whether genetic variants of lipid metabolism-related genes are associated with increased susceptibility to nonalcoholic fatty liver disease (NAFLD) in obese children.

Methods

A cohort of 100 obese children aged 6 to 18 years were divided into NAFLD and non-NAFLD groups and subjected to hepatic ultrasound, anthropometric, and biochemical analyses. We evaluated the association of genetic variants with NAFLD susceptibility by investigating the single nucleotide polymorphisms in each of 36 lipid-metabolism-related genes. The panel genes were assembled for target region sequencing. Correlations between single nucleotide variations, biochemical markers, and clinical phenotypes were analyzed.

Results

97 variants in the 36 target genes per child were uncovered. Twenty-six variants in 16 genes were more prevalent in NAFLD subjects than in in-house controls. The mutation rate of MTTP rs2306986 and SLC6A2 rs3743788 was significantly higher in NAFLD subjects than in non-NAFLD subjects (OR: 3.879; P = 0.004; OR: 6.667, P = 0.005). Logistic regression analysis indicated the MTTP variant rs2306986 was an independent risk factor for NAFLD (OR: 23.468, P = 0.044).

Conclusions

The results of this study, examining a cohort of obese children, suggest that the genetic variation at MTTP rs2306986 was associated with higher susceptibility to NAFLD. This may contribute to the altered lipid metabolism by disruption of assembly and secretion of lipoprotein, leading to reducing fat export from the involved hepatocytes.

Pediatric Non-Alcoholic Fatty Liver Disease

With the increase in the prevalence of obesity, non-alcoholic fatty liver disease (NAFLD) has become among the leading causes of chronic liver disease in the pediatric age group. Once believed to be a “two-hit process”, it is now clear that the actual pathophysiology of NAFLD is complex and involves multiple pathways. Moreover, NAFLD is not always benign, and patients with non-alcoholic steatohepatitis (NASH) are at increased risk of developing advanced stages of liver disease. It has also been shown that NAFLD is not only a liver disease, but is also associated with multiple extrahepatic manifestations, including cardiovascular diseases, type 2 diabetes, and low bone mineral density. Although the data is scarce in the pediatric population, some studies have suggested that long-term mortality and the requirement of liver transplantation will continue to increase in patients with NAFLD. More studies are needed to better understand the natural history of NAFLD, especially in the pediatric age group.

What is the appropriate strategy for diagnosing NAFLD using ultrasonography in obese children?

BACKGROUND

The aim of this study is to identify obese children who are candidates for a potential diagnosis of non-alcoholic fatty liver disease (NAFLD).

METHODS

We enrolled 242 obese children (122 boys and 120 girls) aged 7-16 years who were examined with abdominal ultrasonography in our pediatric obesity clinic. We compared patients in the normal group with those in the NAFLD group (mild disease, moderate to severe disease) and identified the optimal anthropometric parameters among height, weight, body mass index (BMI), waist circumference, hip circumference, waist to height ratio (WHtR), and waist to hip ratio to predict NAFLD using a receiver operating characteristic curve analysis. We also investigated risk factors associated with NAFLD for the anthropometric parameters and the biochemical model using logistic regression.

RESULTS

The high- and low-risk groups for hepatic steatosis relative to a WHtR of 0.56 as the standard point showed significant differences in hepatic steatosis severity grade (P<0.001), BMI (P=0.004), hip circumference (P=0.090), aspartate aminotransferase (P<0.001), alanine aminotransferase (P<0.001), triglycerides (P=0.001), and the triglyceride to high-density lipoprotein (HDL) cholesterol ratio (P=0.006). Risk factors for hepatic steatosis on logistic regression analysis were male sex (odds ratio: 3.68, 95% confidence interval: 1.76-7.70), WHtR >0.56 (2.25, 1.05-4.81), and waist circumference >90th percentile (20.22, 9.21-44.36) in the anthropometric parameter model and elevated alanine aminotransferase levels (boys >25.8 U/L, girls >22.1 U/L) (6.93, 2.52-19.03), hypertriglyceridemia (>110 mg/dL) (3.80, 1.23-11.75), and triglyceride to HDL cholesterol ratio >3 (9.23, 2.95-8.83) in the biochemical parameter model.

CONCLUSION

A diagnostic approach to hepatic steatosis is recommended as part of the proper screening and stratification of risk factors in obese children. WHtR is a simple and convenient method of effectively identifying obese children who are candidates for hepatic steatosis screening.

Prevalence and Correlates of Suspected Nonalcoholic Fatty Liver Disease in Chinese Children

Nonalcoholic fatty liver disease (NAFLD) has become a serious public health problem worldwide; however, the availability of information on the prevalence of NAFLD in the general pediatric population is still limited. The primary aim of this study was to reveal the prevalence and correlates of suspected NAFLD in Chinese children at the national level. Data from the China Health and Nutrition Surveys (CHNS) was used. Weight, height, waist circumference (WC), blood pressure (BP) were measured for children aged 7–18 years. Blood samples were collected and analyzed. Children were classified as having suspected NAFLD if common causes of liver disease were excluded, and serum alanine aminotransferase (ALT) values were above the established thresholds (>22.1 IU/L for girls and >25.8 IU/L for boys). A percentage of 9.03% (75 out of 831) of Chinese children was found to have suspected NAFLD. Overweight and obesity according to BMI percentiles, abdominal obesity, hyperuricemia (uric acid (UA) > 327 μmol/L), and elevated total cholesterol (TC) were all detected as the correlates of childhood suspected NAFLD when adjusting for other factors. Our study revealed the prevalence of suspected NAFLD in general Chinese children at the national level for the first time. Our findings indicate that suspected NAFLD in children is associated with increasing childhood morbidities, further studies are needed to better understand the prevalence of childhood NAFLD and its correlates, and large-scale programs should be launched to screen NAFLD in the pediatric population in China.

Serum Pentraxin 3 Fragment as a Noninvasive Marker of Nonalcoholic Fatty Liver Disease in Obese Children and Adolescents

BACKGROUND/AIMS

It was suggested that serum pentraxin 3 (PTX3) levels could differentiate obese children with nonalcoholic steatohepatitis (NASH) from those with simple steatosis. Thus, we aimed to evaluate the clinical utility of serum PTX3 fragment levels in the diagnosis of NASH and the assessment of its severity in obese children with suspected nonalcoholic fatty liver disease (NAFLD).

METHODS

Fifty obese children were compared to 25 matched controls. All were subjected to history taking, anthropometric measurements, and abdominal ultrasonography, as well as laboratory assessments of liver functions, fasting lipid profile, fasting blood glucose, fasting insulin, homeostasis model assessment (HOMA) index, fasting glucose/insulin ratio, and serum PTX3.

RESULTS

PTX3 was higher in obese cases than controls (p = 0.0001). Eighty percent of the cases had NAFLD with progressive increases in PTX3 levels as the severity of fatty liver increased (p = 0.0001). Moreover, PTX3 was higher in cases with elevated liver enzymes (3.205 ± 0.77 U/l) than those with normal liver enzymes (2.77 + 0.69 U/l, p < 0.0001). A cutoff value of 3.03 U/l differentiated fatty liver from NASH with a sensitivity of 89% and a specificity of 86%.

CONCLUSION

Noninvasive monitoring of serum PTX3 fragment levels in obese patients with suspected NAFLD may be used as a reliable tool for differentiating NASH from simple fatty liver.

Childhood predictors of adult fatty liver. The Cardiovascular Risk in Young Finns Study

BACKGROUND & AIMS

Fatty liver is a potentially preventable cause of serious liver diseases. This longitudinal study aimed to identify childhood risk factors of fatty liver in adulthood in a population-based group of Finnish adults.

METHODS

Study cohort included 2,042 individuals from the Cardiovascular Risk in Young Finns Study aged 3-18years at baseline in 1980. During the latest follow-up in 2011, the liver was scanned by ultrasound. In addition to physical and environmental factors related to fatty liver, we examined whether the genetic risk posed by a single nucleotide polymorphism in the patatin-like phospholipase domain-containing protein 3 gene (PNPLA3) (rs738409) strengthens prediction of adult fatty liver.

RESULTS

Independent childhood predictors of adult fatty liver were small for gestational age, (odds ratio=1.71, 95% confidence interval=1.07-2.72), variant in PNPLA3 (1.63, 1.29-2.07 per one risk allele), variant in the transmembrane 6 superfamily 2 gene (TM6SF2) (1.57, 1.08-2.30), BMI (1.30, 1.07-1.59 per standard deviation) and insulin (1.25, 1.05-1.49 per standard deviation). Childhood blood pressure, physical activity, C-reactive protein, smoking, serum lipid levels or parental lifestyle factors did not predict fatty liver. Risk assessment based on childhood age, sex, BMI, insulin levels, birth weight, TM6SF2 and PNPLA3 was superior in predicting fatty liver compared with the approach using only age, sex, BMI and insulin levels (C statistics, 0.725 vs. 0.749; p=0.002).

CONCLUSIONS

Childhood risk factors on the development of fatty liver were small for gestational age, high insulin and high BMI. Prediction of adult fatty liver was enhanced by taking into account genetic variants in PNPLA3 and TM6SF2 genes.

LAY SUMMARY

The increase in pediatric obesity emphasizes the importance of identification of children and adolescents at high risk of fatty liver in adulthood. We used data from the longitudinal Cardiovascular Risk in Young Finns Study to examine the associations of childhood (3-18years) risk variables with fatty liver assessed in adulthood at the age of 34-49years. The findings suggest that a multifactorial approach with both lifestyle and genetic factors included would improve early identification of children with a high risk of adult fatty liver.

Non-Alcoholic Fatty Liver Disease (NAFLD) in children and adolescents with Prader-Willi Syndrome (PWS)

We tested the hypothesis that patients with Prader-Willi syndrome (PWS) may be at lower risk of developing non-alcoholic fatty liver disease (NAFLD) because of a higher insulin sensitivity. Twenty-one PWS patients and 42 control subjects closely similar for age, gender, pubertal stage and body mass index (CNT), were studied. Metabolic profile and body composition were assessed. NAFLD was established by a validated method of US grading (range from G0 to G3). PWS patients showed a significantly better metabolic profile (lower waist circumference, fasting glucose levels, HOMA-IR, cholesterol, transaminase levels and trunk fat mass/fat mass ratio). Furthermore, NAFLD G1stage was significantly more frequent in PWS subjects (P < 0.05), whereas G2 stage was significantly more frequent in control patients (P < 0.05). NAFLD grading seems to correlate with body composition in PWS, also after adjustment for sex and GH treatment. To our knowledge, this is the first report suggesting a reduced risk of NAFLD in PWS children.

Relationship between Neck Circumference and Non-Alcoholic Fatty Liver Disease in Childhood Obesity

OBJECTIVE

The aim of this study was to establish the association between anthropometric parameters and non-alcoholic fatty liver disease (NAFLD) and to determine the most reliable measurement as a parameter in predicting NAFLD.

METHODS

Two-hundred fifty-three obese children of ages 10 to 18 years were enrolled in this study. Anthropometric data and metabolic parameters such as fasting blood glucose, insulin and lipid levels, were measured. Liver function tests were assessed. NAFLD was determined by ultrasound.

RESULTS

Most metabolic parameters and anthropometric indices were significantly higher in children with NAFLD. A univariate logistic regression analysis was performed, taking NAFLD status as the dependent variable and anthropometric parameters as the independent variables. NAFLD was affected significantly by the anthropometric values. The multiple logistic regression analysis showed that neck circumference (NC) was the only parameter which determined the risk in both genders. Each 1 cm increase in the NC increased the risk of NAFLD 1.544-fold (p<0.001, 95% confidence interval (CI): 1.357-2.214) in the boys and 1.733-fold (p=0.001, 95% CI: 1.185-2.012) in the girls. Receiver operating characteristic analysis was performed to compare the reliability of anthropometric measurements. NC was observed to be a better indicator.

CONCLUSION

Measurement of the NC was shown to be associated with NAFLD in children. We suggest the use of NC as a novel, simple, practical, and reliable anthropometric index in predicting children at risk for NAFLD.

Assessment of Cardiovascular Parameters in Obese Children and Adolescents with Non-Alcoholic Fatty Liver Disease

OBJECTIVE

The aim of this study was to evaluate the periaortic fat thickness (PAFT) using conventional echocardiography in obese children and adolescents with non-alcoholic fatty liver disease (NAFLD).

METHODS

Two hundred and ninety-seven obese children and adolescents were included in the study. Anthropometric measurements were made in all subjects, and fasting venous blood samples were taken for determination of glucose, insulin, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Ultrasonography of the liver was used for assessment of NAFLD and the subjects were grouped as NAFLD and non-NAFLD. Echocardiography was performed in all subjects.

RESULTS

PAFT was higher in patients with NAFLD compared with the non-NAFLD group. In patients with NAFLD, PAFT was positively correlated with waist circumference and with total cholesterol levels. In multiple regression analysis, waist circumference (β=0.28, p=<0.001) was found to be the best predictor of PAFT.

CONCLUSION

Conventional echocardiography may be used to determine increased PAFT at an early stage in obese children and adolescents with NAFLD for careful monitoring of cardiovascular risk.

Obesity and Gestational Diabetes Mellitus Pathways for Programming in Mouse, Monkey, and Man—Where Do We Go Next? The 2014 Norbert Freinkel Award Lecture

Obesity and gestational diabetes mellitus continue to increase worldwide and span the spectrum of age, race, ethnicity, and socioeconomic status. Alarmingly, 1 in 10 infants and toddlers is obese, and 1 in 5 youths is both obese and at risk for metabolic syndrome prior to puberty. The mechanisms underlying how poor maternal health imparts risk for future metabolic disease in the offspring are beginning to emerge in deeply phenotyped human and nonhuman primate models. Maternal diet and obesity impact fuels, hormones, and inflammation with powerful effects on fetal metabolic systems. These are accompanied by persistent changes in the infant microbiome and epigenome and in offspring behavior. These results suggest that gestational and lactational dietary exposures are driving health risks in the next generation. Whether maternal diet can prevent changes in the womb to alter infant life-course disease risk is still unknown. Controlled, mechanistic studies to identify interventions are sorely needed for a healthier next generation.

Non-alcoholic fatty liver and metabolic syndrome in children: a vicious circle

During the last decade, paediatricians have observed a dramatic increase of non-alcoholic fatty liver disease (NAFLD) and metabolic syndrome (MS) in children. Furthermore, several lines of evidence have reported that a large part of children with NAFLD presents one or more traits of MS making plausible that, in the coming years, these subjects may present a rapid course of disease towards more severe cirrhosis and cardiovascular disease. Genetic susceptibility and the pressure of intrauterine environment and lifestyle are all crucial to activate molecular machinery that leads to development of NAFLD and MS in childhood. In this scenario, central obesity and consequent adipose tissue inflammation are critical to promote both MS-associated metabolic dysfunctions and NAFLD-related hepatic damage. An excessive dietary intake may in fact cause a specific lipid partitioning and induce metabolic stressors, which in turn promote insulin resistance and the release of several circulating factors. These molecules, on the one hand, trigger steatosis and the inflammatory response that characterize liver damage in NAFLD, and on the other hand contribute to the onset of other features of MS. This review provides an overview of current genetic, pathogenetic and clinical evidence of the vicious circle created by NAFLD and MS in children.

Challenges and opportunities in drug and biomarker development for nonalcoholic steatohepatitis: findings and recommendations from an American Association for the Study of Liver Diseases-U.S. Food and Drug Administration Joint Workshop

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease (CLD) in North America. It is a growing contributor to the burden of CDL requiring liver transplantation. Cirrhosis is also associated with an increased risk of hepatocellular cancer, which may occur even in the absence of cirrhosis in subjects with nonalcoholic steatohepatitis (NASH), the histological form of NAFLD associated with increased liver-related mortality. The diagnosis of NASH currently requires a liver biopsy. There are also no U.S. Food and Drug Administration (FDA)-approved therapies for NASH. Therefore, there is a need to develop better diagnostic and therapeutic strategies for patients with NASH, targeting both those with early-stage disease as well as those with advanced liver fibrosis. There are unique challenges in the design of studies for these target populations. The long relatively asymptomatic time interval in the progression of NAFLD and NASH to cirrhosis and ultimately liver failure, along with gaps in knowledge regarding disease modifiers, combine to present significant challenges in trial design. Therefore, there is an urgent need to develop methods to identify the populations at particular risk of disease progression and validate endpoints that reflect meaningful changes in health status in this population. This article summarizes the discussion at a joint workshop held September 5 and 6, 2013 in Silver Spring, Maryland, sponsored by the FDA and the American Association for the Study of Liver Diseases to develop guidance on diagnostic and therapeutic modalities for NASH.

Plasma cathepsin D levels: a novel tool to predict pediatric hepatic inflammation

OBJECTIVES

Nonalcoholic steatohepatitis (NASH) is the most severe form of a hepatic condition known as nonalcoholic fatty liver disease (NAFLD). NASH is histologically characterized by hepatic fat accumulation, inflammation, and ballooning, and eventually coupled with fibrosis that, in turn, may progress to end-stage liver disease even in young individuals. Hence, there is a critical need for specific noninvasive markers to predict hepatic inflammation at an early age. We investigated whether plasma levels of cathepsin D (CatD), a lysosomal protease, correlated with the severity of liver inflammation in pediatric NAFLD.

METHODS

Liver biopsies from children (n=96) with NAFLD were histologically evaluated according to the criteria of Kleiner (NAFLD activity score) and the Brunt's criteria. At the time of liver biopsy, blood was taken and levels of CatD, alanine aminotransferase (ALT), and cytokeratin-18 (CK-18) were measured in plasma.

RESULTS

Plasma CatD levels were significantly lower in subjects with liver inflammation compared with steatotic subjects. Furthermore, we found that CatD levels were gradually reduced and corresponded with increasing severity of liver inflammation, steatosis, hepatocellular ballooning, and NAFLD activity score. CatD levels correlated with pediatric NAFLD disease progression better than ALT and CK-18. In particular, CatD showed a high diagnostic accuracy (area under receiver operating characteristic curve (ROC-AUC): 0.94) for the differentiation between steatosis and hepatic inflammation, and reached almost the maximum accuracy (ROC-AUC: 0.998) upon the addition of CK-18.

CONCLUSIONS

Plasma CatD holds a high diagnostic value to distinguish pediatric patients with hepatic inflammation from children with steatosis.

Childhood obesity in specialist care--searching for a healthy obese child

INTRODUCTION

One in three obese adults is classified as metabolically healthy, but there is less evidence in obese children. We studied the overall clinical presentation of Finnish obese children and the prevalence of cardiometabolic risk factors with child-specific cut-offs.

MATERIAL AND METHODS

This is a cross-sectional register-based study of 2-18-year-old children (n = 900) evaluated for obesity in three hospitals in 2005-2012. Clinical and metabolic data were related to sex, age, puberty, and obesity grade and analyzed using chi-square and non-parametric tests.

RESULTS

In 80% of cases at least one cardiovascular risk factor was present. Only 3% of subjects for whom complete metabolic data were available (n = 360) had no metabolic disorder. Systolic blood pressure was hypertensive in 50.2% and diastolic in 14.5% of the children. The youngest children had highest body mass index SD score. Obesity was more severe in boys than girls (p < 0.001). Hypertensive systolic blood pressure values (p = 0.012), prediabetes (p < 0.001), fatty liver (p < 0.001), and dyslipidemia (p = 0.025) were more prevalent in 15-18-year-old boys than girls.

CONCLUSION

Most obese children in specialist care have cardiovascular risk factors; this indicates that earlier intervention is needed.

Targeting fibroblast growth factor 19 in liver disease: a potential biomarker and therapeutic target

INTRODUCTION

Fibroblast growth factor 19 (FGF19) is a member of the hormone-like FGF family and has activity as an ileum-derived postprandial hormone. It shares high binding affinity with β-Klotho and together with the FGF receptor (FGFR) 4, is predominantly targeted to the liver. The main function of FGF19 in metabolism is the negative control of bile acid synthesis, promotion of glycogen synthesis, lipid metabolism and protein synthesis.

AREAS COVERED

Drawing on in vitro and in vivo studies, this review discusses FGF19 and some underlying mechanisms of action of FGF19 as an endocrine hormone in several liver diseases. The molecular pathway of the FGF19-FGFR4 axis in non-alcoholic liver disease and hepatocellular carcinoma are discussed. Furthermore, definition of function and pharmacological effects of FGF19 for liver disease are also presented.

EXPERT OPINION

A series of studies have highlighted a crucial role of FGF19 in liver disease. However, the conclusions of these studies are partly paradoxical and controversial. An understanding of the underlying biological mechanisms which may explain inconsistent findings is especially important for consideration of potential biomarker strategies and an exploration of the putative therapeutic efficacy of FGF19 for human liver disease.

Association of ALT and the metabolic syndrome among Mexican children

Nonalcoholic fatty liver disease (NAFLD) is emerging as a component of the metabolic syndrome (MetS); Hispanics being particularly predisposed. Alanine aminotransferase (ALT) is considered a marker of NAFLD. The aim of this study was to determine the prevalence and associations between ALT elevations and MetS in normal-weight, overweight and obese Mexican children and adolescents, since data in Mexico is scarce. Body mass index (BMI), waist circumference (WC), percentage body fat, blood pressure, glucose, lipid profiles, ALT and aspartate aminotransferase (AST) were measured in 236, 6-12yo normal-weight, overweight and obese Mexicans from eight public schools. The results showed that elevated ALT (>40 IU/L) was found in 17.7% of the obese and overweight population, with no gender difference. The prevalence of elevated ALT increased linearly across BMI categories (p = 0.001), from 0.0% for the normal-weight group (95%CI 0.0-€“8.0) to 22.4% for the obese one (95%CI 16.2-€“30.2). AST/ALT ratio <1 also increased linearly, as did the prevalence of MetS (p = 0.001), from 0.0% for the normal-weight group to 40.3% for the obese one. The prevalence of MetS was strongly associated with elevated ALT (p = 0.002), 50% in the elevated ALT group (95%CI 34.1-€“65.9) and 24.1% in the normal ALT one (95%CI 18.1-€“31.3). There was also a strong association between MetS and an AST/ALT ratio <1. WC was the best predictor of elevated ALT (AOR = 7.13). Pearson correlation showed that MetS components were significantly correlated with elevated ALT. Therefore elevated ALT levels were highly prevalent and strongly associated with MetS in Mexican children, it should be screened in overweight and obese children.

Dietary fructose reduction improves markers of cardiovascular disease risk in Hispanic-American adolescents with NAFLD

Nonalcoholic fatty liver disease (NAFLD) is now thought to be the most common liver disease worldwide. Cardiovascular complications are a leading cause of mortality in NAFLD. Fructose, a common nutrient in the westernized diet, has been reported to be associated with increased cardiovascular risk, but its impact on adolescents with NAFLD is not well understood. We designed a 4-week randomized, controlled, double-blinded beverage intervention study. Twenty-four overweight Hispanic-American adolescents who had hepatic fat >8% on imaging and who were regular consumers of sweet beverages were enrolled and randomized to calorie-matched study-provided fructose only or glucose only beverages. After 4 weeks, there was no significant change in hepatic fat or body weight in either group. In the glucose beverage group there was significantly improved adipose insulin sensitivity, high sensitivity C-reactive protein (hs-CRP), and low-density lipoprotein (LDL) oxidation. These findings demonstrate that reduction of fructose improves several important factors related to cardiovascular disease despite a lack of measurable improvement in hepatic steatosis. Reducing dietary fructose may be an effective intervention to blunt atherosclerosis progression among NAFLD patients and should be evaluated in longer term clinical trials.

Low 25-hydroxyvitamin D level is associated with insulin sensitivity in obese adolescents with non-alcoholic fatty liver disease

AIM

The aim of this study was to investigate the relationships between 25-hydroxy-vitamin D (25(OH)D) and insulin resistance in obese adolescents with non-alcoholic fatty liver disease (NAFLD).

PATIENTS AND METHODS

Eighty-seven obese adolescents (45 girls and 42 boys, mean age: 12.7 ± 1.3 years, mean body mass index standard deviation score (BMI-SDS): 2.1 ± 0.3) and 30 lean subjects (15 girls and 15 boys, mean age: 12.3 ± 1.45 years, mean BMI-SDS: 0.5 ± 0.7) were enrolled for the study. The obese subjects were divided into two subgroups based on the presence or absence of fatty liver with high transaminases (NAFLD group and non-NAFLD group). Fasting blood samples were assayed for 25(OH)D, transaminases, glucose, and insulin levels. Insulin resistance was calculated by the homeostasis model assessment (HOMA-IR).

RESULTS

25(OH)D measurements were decreased in both obese groups (NAFLD and non-NAFLD) in comparison with the lean group (29.5 ± 18.4 vs. 41.0 ± 17.9 vs. 48.1 ± 22.2 ng/mL). However; the NAFLD group had significantly lower measurements of 25(OH)D than the non-NAFLD group (p < 0.001) and lean group (p < 0.001). 25(OH)D was negatively correlated with HOMA-IR (r = 0.158, p = 0.01) and with alanine aminotransferase (r = 0.794, p = 0.03) in the NAFLD obese group. There was no significant associations between fasting insulin, BMI-SDS and 25(OH)D in obese groups.

CONCLUSION

We suggest that low 25(OH)D occurs commonly in obese adolescents with NAFLD and we demonstrated an association between insufficient vitamin D status and low insulin sensitivity in obese adolescents with NAFLD.

Role of vitamin D in children with hepatosteatosis

BACKGROUND

The increasing incidence of obesity in children is a significant risk factor for nonalcoholic fatty liver disease and obesity-associated morbidity. Vitamin D has a major role in bone mineral metabolism and has antimicrobial, antioxidant properties. In this study we aimed to investigate the role of vitamin D in children with obesity with hepatosteatosis.

METHODS

A total of 101 children with obesity were included in this study. Hepatosteatosis was diagnosed and graded using ultrasonography. Serum levels of 25-hydroxyvitamin D (25-(OH) vitamin D), calcium, phosphate, alkaline phosphatase, and parathormone were tested. Two-sided t test and Pearson χ tests were used for the relation between vitamin D and hepatosteatosis.

RESULTS

In our study group, 45.5% were girls (n=46) and the mean age was 11.5 ± 2.8 years (range 3-17 years). Hepatosteatosis was identified in 58 children (57.4%). The diagnosis of grade 1 and grade 2 hepatosteatosis was made in 41 (40.6%) and 17 (16.8%) children, respectively. Median serum 25-(OH) vitamin D levels in children without hepatosteatosis was 16.4 ng/mL (interquartile range 12.4-24.8 ng/mL), whereas children with grade 1 and grade 2 hepatosteatosis had 25-(OH) vitamin D levels of 14.2 ng/mL (interquartile range 9.5-21.2 ng/mL) and 11.5 ng/mL (interquartile range 7.5-16.7 ng/mL), respectively (P=0.005). There was a positive correlation between insulin resistance and the grade of hepatosteatosis (P=0.03).

CONCLUSIONS

Serum vitamin D levels in children with obesity with hepatosteatosis are significantly lower than vitamin D levels in children with obesity without hepatosteatosis. In this observational study we only refer to the association of vitamin D deficiency/insufficiency with hepatosteatosis.

Macrophages and fibrosis in adipose tissue are linked to liver damage and metabolic risk in obese children

OBJECTIVE

Obesity in childhood is associated with an inflammatory state in adipose tissue and liver, which elevates risk for diabetes and liver disease. No prior study has examined associations between pathologies occurring in adipose tissue and liver to identify elements of tissue damage associated with type 2 diabetes risk. This study sought to determine whether inflammation and fibrosis in abdominal subcutaneous adipose tissue (SAT) in obese/overweight children (BMI-z 2.3 ± 0.76) was related to the extent of observed liver disease or type 2 diabetes risk.

METHODS

Biopsy samples of abdominal (SAT) and liver were simultaneously collected from 33 Italian children (mean BMI 28.1 ± 5.1 kg/m(2) and mean age 11.6 ± 2.2 years) with confirmed NAFLD. Histology and immunohistochemistry were conducted on biopsies to assess inflammation and fibrosis in adipose tissue and fibrosis and inflammation in liver.

RESULTS

Presence vs. absence of crown-like structures (CLS) in SAT was significantly related to liver fibrosis scores (1.7 ± 0.7 vs. 1.2 ± 0.7, P = 0.04) independent of BMI. SAT fibrosis was significantly correlated with a lower disposition index (r = -0.48, P = 0.006). No other adipose measures were associated with liver disease parameters.

CONCLUSION

Markers of subcutaneous white adipose tissue inflammation are associated with greater extent of liver fibrosis independent of obesity and SAT fibrosis may contribute to diabetes risk through reduced insulin secretion.

Nonalcoholic Fatty liver disease/non-alcoholic steatohepatitis in childhood: endocrine-metabolic "mal-programming"

CONTEXT

Nonalcoholic Fatty Liver Disease (NAFLD) is the major chronic liver disease in the pediatric population. NAFLD includes a broad spectrum of abnormalities (inflammation, fibrosis and cirrhosis), ranging from accumulation of fat (also known as steatosis) towards non-alcoholic steatohepatitis (NASH). The development of NAFLD in children is significantly increased.

EVIDENCE ACQUISITION

A literature search of electronic databases was undertaken for the major studies published from 1998 to today. The databases searched were: PubMed, EMBASE, Orphanet, Midline and Cochrane Library. We used the key words: "non-alcoholic fatty liver disease, children, non-alcoholic steatohepatitis and fatty liver".

RESULTS

NAFLD/NASH is probably promoted by "multiple parallel hits": environmental and genetic factors, systemic immunological disorders (oxidative stress, persistent-low grade of inflammation) as well as obesity and metabolic alterations (insulin resistance and metabolic syndrome). However its exact cause still underdiagnosed and unknown.

CONCLUSIONS

Pediatric NAFLD/NASH is emerging problem. Longitudinal follow-up studies, unfortunately still insufficient, are needed to better understand the natural history and outcome of NAFLD in children. This review focuses on the current knowledge regarding the epidemiology, pathogenesis, environmental, genetic and metabolic factors of disease. The review also highlights the importance of studying the underlying mechanisms of pediatric NAFLD and the need for complete and personalized approach in the management of NAFLD/NASH.

Histological abnormalities in children with nonalcoholic fatty liver disease and normal or mildly elevated alanine aminotransferase levels

OBJECTIVE

To investigate the histological spectrum of nonalcoholic fatty liver disease (NAFLD) in children with normal, mildly elevated (26-50 U/L boys, 23-44 U/L girls), or elevated (>50 U/L in boys, >44 U/L in girls) serum alanine aminotransferase (ALT) levels.

STUDY DESIGN

The Nonalcoholic Steatohepatitis Clinical Research Network enrolls children aged 5-18 years with NAFLD. We analyzed baseline clinical and histological data from 91 children with suspected NAFLD and normal or mildly elevated ALT and liver biopsy analysis within 180 days of ALT measurement, and compared them with data from 392 children with elevated ALT.

RESULTS

Seventeen of the 91 children with suspected NAFLD (19%) had a normal ALT level, and 74 (81%) had a mildly elevated ALT level. Overall, 45% of the biopsy specimens analyzed had steatosis ≥33%, 22% had grade ≥2 lobular inflammation, 81% had portal inflammation, 29% had ballooned hepatocytes, 35% had "suspicious/borderline" steatohepatitis, 8% had definite nonalcoholic steatohepatitis, 34% had an NAFLD activity score ≥4, and 46% had fibrosis (38% mild/moderate and 8% bridging/cirrhosis). Marked steatosis (50% vs 24%) and fibrosis (54% vs 12%) were significantly more common in the patients with mildly elevated ALT compared with those with normal ALT, with no difference in ballooning, inflammation, or NAFLD activity score ≥4 between the 2 groups. Fibrosis stage 3/4 was seen in none of the children with normal ALT, in 9% of those with mildly elevated ALT, and in 15% of those with elevated ALT.

CONCLUSION

Liver biopsy specimens from children with NAFLD with normal or mildly elevated ALT levels show significant histological abnormalities, including advanced fibrosis in children with mildly elevated ALT. Thus, measurement of ALT may underestimate liver injury in NAFLD. The use of appropriate ALT cutoff levels can help identify children at risk for more severe disease.

Influence of dietary pattern, physical activity, and I148M PNPLA3 on steatosis severity in at-risk adolescents

Evidence relating dietary patterns to obesity and related disorders such as non-alcoholic fatty liver disease (NAFLD) is limited in pediatric age. Aim of this study was to analyze the association between dietary patterns, obesity and development of severe steatosis and the metabolic syndrome in a series of children and adolescents referred for suspected NAFLD, and the interaction with the rs738409 I148M PNPLA3 polymorphism. Two hundred patients (112 females) had completed a food frequency and demographic questionnaire. Nearly 58 % were obese, and 32 % were overweight. Mild, moderate, and severe fatty liver was present in 60 (30 %), 87 (44 %), and 51 (26 %) participants, respectively. A great proportion of overweight/obese children and adolescents reported a correct dietary pattern. At multivariate ordinal regression analysis considering demographic, anthropometric, genetic, and behavioral determinants, the major determinant of steatosis severity was PNPLA3 I148M genotype (p < 0.0001), followed by older age (p = 0.017), higher waist circumference (p = 0.016), and less time spent practising physical exercise (p = 0.034). Furthermore, there was a significant interaction between PNPLA3 I148M and intake of sweetened beverages (p = 0.033) and of vegetables (p = 0.038). In conclusion, although dietary pattern was reportedly correct in at-risk overweight adolescents with NAFLD, we report a novel interaction between PNPLA3 I148M and dietary components with the severity of steatosis.

Obstructive sleep apnea syndrome affects liver histology and inflammatory cell activation in pediatric nonalcoholic fatty liver disease, regardless of obesity/insulin resistance

RATIONALE

Obstructive sleep apnea syndrome (OSAS) and nonalcoholic fatty liver disease (NAFLD) are frequently encountered in obese children. Whether OSAS and intermittent hypoxia are associated with liver injury in pediatric NAFLD is unknown.

OBJECTIVES

To assess the relationship of OSAS with liver injury in pediatric NAFLD.

METHODS

Sixty-five consecutive children with biopsy-proven NAFLD (age, mean ± SD, 11.7 ± 2.1 yr; 58% boys; body mass index z score, 1.93 ± 0.61) underwent a clinical-biochemical assessment and a standard polysomnography. Insulin sensitivity, circulating proinflammatory cytokines, markers of hepatocyte apoptosis (cytokeratin-18 fragments), and hepatic fibrogenesis (hyaluronic acid) were measured. Liver inflammatory infiltrate was characterized by immunohistochemistry for CD45, CD3, and CD163, surface markers of leukocytes, T cells, and activated macrophage/Kupffer cells, respectively. OSAS was defined by an apnea/hypopnea index (AHI) greater than or equal to 1 event/h, and severe OSAS was defined by an AHI greater than or equal to 5 events/h.

MEASUREMENTS AND MAIN RESULTS

Fifty-five percent of children with NAFLD had nonalcoholic steatohepatitis (NASH), and 34% had significant (stage F ≥ 2) fibrosis. OSAS affected 60% of children with NAFLD; the presence and severity of OSAS were associated with the presence of NASH (odds ratio, 4.89; 95% confidence interval, 3.08-5.98; P = 0.0001), significant fibrosis (odds ratio, 5.91; 95% confidence interval, 3.23-7.42; P = 0.0001), and NAFLD activity score (β, 0.347; P = 0.029), independently of body mass index, abdominal adiposity, metabolic syndrome, and insulin resistance. This relationship held also in nonobese children with NAFLD. The duration of hemoglobin desaturation (Sa(O2) < 90%) correlated with increased intrahepatic leukocytes and activated macrophages/Kupffer cells and with circulating markers of hepatocyte apoptosis and fibrogenesis.

CONCLUSIONS

In pediatric NAFLD, OSAS is associated with biochemical, immunohistochemical, and histological features of NASH and fibrosis. The impact of hypoxemia correction on liver disease severity warrants evaluation in future trials.

Fatty liver in childhood

Fatty liver is a growing health problem worldwide. It might evolve to nonalcoholic steatohepatitis, cirrhosis and cause hepatocellular carcinoma. This disease, which has increased because of eating habits, changes in food content and lifestyle, affects people from childhood. The most important risk factors are obesity and insulin resistance. Besides these factors, gender, ethnicity, genetic predisposition and some medical problems are also important. Cirrhosis in children is rare but is reported. Nonalcoholic fatty liver disease (NAFLD) has no specific symptoms or signs but should be considered in obese children. NAFLD does not have a proven treatment. Weight loss with family based treatments is the most acceptable management. Exercise and an applicable diet with low glycemic index and appropriate calorie intake are preferred. Drugs are promising but not sufficient in children for today.

Maternal and in utero determinants of type 2 diabetes risk in the young

The global prevalence of diabetes mellitus has reached epidemic proportions. In 2010, it was estimated that 6.4 % of the adult population (285 million) have diabetes. In recent years, the incidence of type 2 diabetes (T2D), a condition traditionally associated with aging, has been steadily increasing among younger individuals. It is now a well-established notion that the early-life period is a critical window of development and that influences during this period can "developmentally prime" the metabolic status of the adult. This review discusses the role of maternal and in utero influences on the developmental priming of T2D risk. Both human epidemiological studies and experimental animal models are beginning to demonstrate that early dietary challenges can accelerate the onset of age-associated metabolic disturbances, including insulin resistance, T2D, obesity, hypertension, and cardiovascular disease. These findings show that poor maternal nutrition can prime a prediabetes phenotype, often manifest as insulin resistance, by very early stages of life. Thus, the maternal diet is a critical determinant of premature T2D risk. While the mechanisms that link early nutrition to age-associated metabolic decline are currently unclear, preliminary findings suggest perturbations in a number of processes involved in cellular aging, such as changes in longevity-associated Sirtuin activity, epigenetic regulation of key metabolic genes, and mitochondrial dysfunction. Preliminary studies show that pharmacological interventions in utero and dietary supplementation in early postnatal life may alleviate insulin resistance and reduce T2D risk. However, further studies are warranted to fully understand the relationship between the early environment and long-term effects on metabolism. Such mechanistic insights will facilitate strategic interventions that prevent accelerated metabolic decline and the premature onset of T2D in the current and future generations.

Developmental origins of nonalcoholic fatty liver disease

Obese pregnant women may transmit their metabolic phenotype to offspring, leading to a cycle of obesity and diabetes over generations. Early childhood obesity predicts nonalcoholic fatty liver disease (NAFLD), the most common chronic human liver disease. The fetus may be vulnerable to steatosis because immature fetal adipose depots are not available to buffer the excess transplacental lipid delivery in maternal obesity. In animal models, in utero high-fat diet exposure results in an increase in the accumulation of liver triglycerides in offspring and increased hepatic oxidative stress and apoptosis, perhaps priming the liver for later development of NAFLD. Innate immune dysfunction and necroinflammatory changes have been observed in postnatal offspring liver of animals born to high-fat-fed dams. Postweaning, livers of offspring exposed to maternal high-fat feeding in utero share pathophysiologic features with human NAFLD, including increased de novo lipogenesis and decreased free fatty acid oxidation. Human studies using magnetic resonance imaging have shown that maternal BMI predicts infant intrahepatocellular lipid storage, as seen in animal models. The generational transfer of NAFLD may occur via epigenetic changes in offspring liver. Transmission of microbiota from mother to infant may impact energy retention and immune function that contribute to a predisposition to NAFLD.