Current Concepts in Pediatric Nonalcoholic Fatty Liver Disease

The Families Improving Health Together (FIT) Program: Initial evaluation of retention and research in a multispecialty clinic for children with obesity

BACKGROUND

Obesity affects ∼17% of US children, with parallel increases in multiple comorbidities, especially among African-, Asian-, Hispanic-, and Native-Americans. Barriers to patient retention in pediatric obesity programs include lack of centralized care, and frequent subspecialty MD visits which conflict with patient school attendance and parental work attendance as well as with support service utilization. Lack of integration of multispecialty clinical care with interdisciplinary research is a major barrier to fuller exploration of the treatment, prevention, and understanding of obesity in childhood.

OBJECTIVE

To test the hypothesis, a novel multispecialty/interdisciplinary clinical and research infrastructure with strong emphasis on a primary obesity care physician for children with early-onset (<9 years) obesity (Families Improving health Together [FIT]) could promote lower patient attrition (primary goal) and foster productive research in pediatric obesity (secondary goal).

RESULTS

Data support the hypotheses. Over 15 months, FIT reported a >90% participant retention (p < 0.001 vs. expected rate based on other studies of similar programs). Though 90% of children had at least one adiposity-related comorbidity and 70% had at least two, there was no need for additional subspecialist visits with cardiologists, endocrinologists, gastroenterologists, or molecular geneticists. Three abstracts were presented at national meetings, and two manuscripts were published all with junior faculty as primary authors.

CONCLUSION

This pilot study suggests that an integrated multispecialty/interdisciplinary approach to children with obesity improves patient retention and can be integrated successfully with research.

Nonalcoholic steatohepatitis: the role of peroxisome proliferator-activated receptors

The increasing epidemic of obesity worldwide is linked to serious health effects, including increased prevalence of type 2 diabetes mellitus, cardiovascular disease and nonalcoholic fatty liver disease (NAFLD). NAFLD is the liver manifestation of the metabolic syndrome and includes the spectrum of liver steatosis (known as nonalcoholic fatty liver) and steatohepatitis (known as nonalcoholic steatohepatitis), which can evolve into progressive liver fibrosis and eventually cause cirrhosis. Although NAFLD is becoming the number one cause of chronic liver diseases, it is part of a systemic disease that affects many other parts of the body, including adipose tissue, pancreatic β-cells and the cardiovascular system. The pathomechanism of NAFLD is multifactorial across a spectrum of metabolic derangements and changes in the host microbiome that trigger low-grade inflammation in the liver and other organs. Peroxisome proliferator-activated receptors (PPARs) are a group of nuclear regulatory factors that provide fine tuning for key elements of glucose and fat metabolism and regulate inflammatory cell activation and fibrotic processes. This Review summarizes and discusses the current literature on NAFLD as the liver manifestation of the systemic metabolic syndrome and focuses on the role of PPARs in the pathomechanisms as well as in the potential targeting of disease.

Complications, morbidity and mortality of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is an increasingly recognized public health problem, affecting up to a quarter of the world's adult population. The burden of NAFLD is influenced by the epidemics of obesity and type 2 diabetes mellitus (T2DM) and the prevalence of these conditions is not expected to decrease in the forthcoming decades. Consequently, the burden of NAFLD-related liver complications (non-alcoholic steatohepatitis [NASH], cirrhosis and hepatocellular carcinoma) and the need for life-saving liver transplantation are also expected to increase further in the near future. A large body of clinical evidence indicates that NAFLD is associated not only with increased liver-related morbidity and mortality, but also with an increased risk of developing other important extra-hepatic diseases, such as cardiovascular disease (that is the predominant cause of death in patients with NAFLD), extra-hepatic cancers (mainly colorectal cancers), T2DM and chronic kidney disease. Thus, NAFLD creates a considerable health and economic burden worldwide and often results in poor quality of life. This narrative review provides an overview of the current literature on main complications, morbidity and mortality of this common and burdensome liver disease.

Cirrhosis in a Young Child Due to Fatty Liver; Importance of Early Screening: A Case Report and Review of the Literature

Patient: Male, 9-year-old

Final Diagnosis: Liver cirrhosis

Symptoms: Abdominal pain • vomiting

Medication:—

Clinical Procedure: CT scan • fibroscan • liver biopsy • ultrasonography

Specialty: Laboratory Diagnostics • Gastroenterology and Hepatology • Pathology • Pediatrics and Neonatology

Heme oxygenase-1 alleviated non-alcoholic fatty liver disease via suppressing ROS-dependent endoplasmic reticulum stress

AIMS

The endoplasmic reticulum (ER) stress response plays a crucial role in the development of nonalcoholic steatohepatitis (NASH). Heme oxygenase-1 (HO-1) exerts beneficial effects against oxidative injury in NASH. This study is aimed to clarify whether HO-1 is an effective therapeutic strategy for NASH via regulation of ER stress.

METHODS

The C57BL/6J mice were fed with methionine-choline deficient (MCD) for 4 weeks and high fat-high carbohydrate-high cholesterol (HFD) diet for 16 weeks, with hemin or zinc protoporphyrin IX (ZnPP-IX), respectively. The LO-2 cells were cultured in palmitic medium, with transfected pEX-HO-1 or sh-HO-1 plasmid for 24 h. Meanwhile, thirty NASH patients and 15 health controls were enrolled. The ER ultrastructure was observed by transmission electron microscopy (TEM) and confocal microscopy. The expressions of mRNAs and proteins of HO-1, ER stress related genes were detected by real time PCR, western blot and immunohistochemical staining, respectively.

RESULTS

The swelled and broken rough endoplasmic reticulums were observed in MCD and HFD fed mice. The reactive hepatic expression of HO-1 was related with the increased ROS production and ER stress, companied with upregulation of GRP78, p-IRE1, PERK, ATF6. Through hemin administration, hepatocyte apoptosis was suppressed companied down-regulation of CHOP, caspase12 and up-regulation of BCL2. Conserved results were exhibited in ZnPP-IX administrated mice and HO-1 silent cells. Consistent results were observed in the NASH Patients.

CONCLUSIONS

HO-1 could serve as a protective factor in the progression of nutritional steatohepatitis by suppresses hepatocyte excessive ER stress and might be a potential target for therapy of nonalcoholic steatohepatitis.

Prevalence of prediabetes and diabetes in children and adolescents with biopsy-proven non-alcoholic fatty liver disease

BACKGROUND & AIMS

We undertook a cross-sectional study of children/adolescents with and without non-alcoholic fatty liver disease (NAFLD) to compare the prevalence of prediabetes and diabetes, and to examine the role of abnormal glucose tolerance as a predictor of liver disease severity.

METHODS

We recruited a cohort of 599 Caucasian children/adolescents with biopsy-proven NAFLD, and 118 children/adolescents without NAFLD, who were selected to be similar for age, sex, body mass index and waist circumference to those with NAFLD. The diagnosis of prediabetes and diabetes was based on either hemoglobin A1c, fasting plasma glucose or 2 h post-load glucose concentrations.

RESULTS

Children/adolescents with NAFLD had a significantly higher prevalence of abnormal glucose tolerance (prediabetes or diabetes) than those without NAFLD (20.6% vs. 11%, p = 0.02). In particular, 124 (20.6%) children/adolescents with NAFLD had abnormal glucose tolerance, with 19.8% (n = 119) satisfying the diagnostic criteria for prediabetes and 0.8% (n = 5) satisfying the criteria for diabetes. The combined presence of prediabetes and diabetes was associated with a nearly 2.2-fold increased risk of non-alcoholic steatohepatitis (NASH; unadjustedodds ratio 2.19; 95% CI 1.47-3.29; p <0.001). However, this association was attenuated (but remained significant) after adjustment for age, sex, waist circumference (adjustedodds ratio 1.69, 95% CI 1.06-2.69, p = 0.032), and the PNPLA3 rs738409 polymorphism. Both this PNPLA3 polymorphism and waist circumference were strongly associated with NASH.

CONCLUSIONS

Abnormal glucose tolerance (especially prediabetes) is highly prevalent among children/adolescents with biopsy-proven NAFLD. These children also have a higher risk of NASH, though central adiposity is the factor that is most strongly associated with NASH.

LAY SUMMARY

Children with biopsy-proven non-alcoholic fatty liver disease (NAFLD) have a higher prevalence of abnormal glucose tolerance (prediabetes or type 2 diabetes) than children without NAFLD. Children with biopsy-proven NAFLD and abnormal glucose tolerance also have a higher prevalence of the progressive form of disease, non-alcoholic steatohepatitis, than those with normal glucose tolerance, though central adiposity is the factor that is most strongly associated with non-alcoholic steatohepatitis.

Association Between Nonalcoholic Fatty Liver Disease and Reduced Bone Mineral Density in Children: A Meta-Analysis

Recent cross-sectional studies have examined the association between nonalcoholic fatty liver disease (NAFLD) and bone mineral density (BMD) in children or adolescents, but these have produced conflicting results. We performed a systematic review and meta-analysis of these published studies to quantify the magnitude of the association, if any, between NAFLD and BMD. We searched publication databases from January 2000 to September 2018, using predefined keywords to identify relevant observational studies conducted in children or adolescents in whom NAFLD was diagnosed either by imaging or by histology and BMD Z score was measured by dual-energy X-ray absorptiometry. Data from selected studies were extracted, and a meta-analysis was performed using random-effects modeling. A total of eight observational cross-sectional or case-control studies enrolling 632 children and adolescents (mean age 12.8 years), 357 of whom had NAFLD, were included in the final analysis. Meta-analysis showed significant differences in whole-body or lumbar BMD Z scores between children/adolescents with and without NAFLD (n = 6 studies; pooled weighted mean difference [WMD], -0.48; 95% confidence interval [CI], -0.74 to -0.21; I² = 55.5%), as well as between those with biopsy-confirmed nonalcoholic steatohepatitis (NASH) and those with no-NASH (n = 4 studies; pooled WMD, -0.27; 95% CI, -0.40 to -0.13; I² = 0%). The aforementioned WMDs in BMD Z scores were independent of common clinical risk factors, such as age, sex, race/ethnicity, and body mass index. Sensitivity analyses did not modify these findings. Funnel plot and Egger test did not reveal significant publication bias. Conclusion: This meta-analysis shows that the presence and severity of NAFLD are significantly associated with reduced whole-body BMD Z scores in children and adolescents; however, the observational design of the studies included does not allow for proving causality.

Assay validation and clinical performance of chronic inflammatory and chemokine biomarkers of NASH fibrosis

Nonalcoholic steatohepatitis (NASH) is a chronic liver disease that can lead to cirrhosis, liver transplant, and even hepatocellular carcinoma. While liver biopsy remains the reference standard for disease diagnosis, analytical and clinical development of non-invasive soluble biomarkers of NASH are of great importance to advance the field. To this end, we performed analytical and clinical validation on a series of pro-inflammatory cytokines and chemokines implicated hepatic inflammation; IL-6, CRP, TNFα, MCP-1, MIP-1β, eotaxin, VCAM-1. Biomarker assays were validated for accuracy and precision. Clinical performance was evaluated in a random sample of 52 patients with biopsy-proven NAFLD/NASH. Patients were categorized into three groups according to their fibrosis stage; advanced (F3-F4), mild (F1-2) and no (F0) fibrosis. Serum IL-6 was increased in patients with advanced fibrosis (2.71 pg/mL; 1.26 pg/mL; 1.39 pg/mL p<0.01) compared to patients with mild or no fibrosis respectively. While, there was no significant difference noted in CRP, TNFα, MCP-1, MIP-1β, eotaxin among the three groups, VCAM-1 levels were increased by 55% (p<0.01) and 40% (p<0.05) in the advanced cohort compared to the mild and no fibrosis groups respectively. VCAM-1 also displayed good clinical performance as a biomarker of advanced fibrosis with an area under the receiver operating curve of 0.87. The VCAM-1 assay demonstrated robust accuracy and precision, and VCAM-1 outperformed IL-6, CRP, TNFα, and the chemokines MCP-1, MIP-1β, and eotaxin as a biomarker of advanced fibrosis in NASH. Addition of biomarkers such as IL-6 and VCAM-1 to panels may yield increased sensitivity and specificity for staging of NASH.

Relationship Between PNPLA3 rs738409 Polymorphism and Decreased Kidney Function in Children With NAFLD

Emerging evidence suggests that patatin-like phospholipase domain-containing protein-3 (PNPLA3) rs738409 genotype (the major genetic variant associated with susceptibility to nonalcoholic fatty liver disease [NAFLD]) is associated with decreased kidney function in adults. Currently, it is uncertain whether this association also occurs in children/adolescents and whether any association is independent of liver disease severity. We enrolled a sample of 142 Caucasian children and adolescents with biopsy-proven NAFLD, presenting to the Liver Unit of the "Bambino Gesù" Children's Hospital. The glomerular filtration rate (e-GFR) was estimated using the Bedside Schwartz equation, whereas 24-hour proteinuria was measured using a radioimmunoassay method. Genotyping for the PNPLA3 rs738409 genotype was undertaken using the single-nucleotide polymorphism genotyping allelic discrimination method. Overall, 45 children had G/G, 56 had G/C, and 41 had C/C PNPLA3 rs738409 genotype, respectively. Children with G/G genotype had significantly lower e-GFR (107.5 ± 20 versus 112.8 ± 18 versus 125.3 ± 23 mL/min/1.73 m² , P = 0.002) and higher 24-hour proteinuria (58.5 ± 21 versus 53.9 ± 22 versus 42.9 ± 20 mg/day, P = 0.012) compared with those with either G/C or C/C genotypes. After adjustment for age, sex, systolic blood pressure, measures of adiposity, homeostasis model assessment-estimated insulin resistance and biopsy-confirmed nonalcoholic steatohepatitis and stage of liver fibrosis, the presence of rs738409 G/G genotype was independently associated with both lower e-GFR (β coefficient: -23.6; 95% confidence interval [CI]: -36.3 to -10.8; P < 0.001) and higher 24-hour proteinuria (β coefficient: 15.3; 95% CI: 1.12 to 30.5; P = 0.046). Conclusion: Regardless of established renal risk factors and the histological severity of NAFLD, the PNPLA3 G/G genotype was strongly associated with decreasing kidney function and increasing 24-hour proteinuria in children/adolescents with histologically confirmed NAFLD.

Platelet GPIbα is a mediator and potential interventional target for NASH and subsequent liver cancer

Non-alcoholic fatty liver disease ranges from steatosis to non-alcoholic steatohepatitis (NASH), potentially progressing to cirrhosis and hepatocellular carcinoma (HCC). Here, we show that platelet number, platelet activation and platelet aggregation are increased in NASH but not in steatosis or insulin resistance. Antiplatelet therapy (APT; aspirin/clopidogrel, ticagrelor) but not nonsteroidal anti-inflammatory drug (NSAID) treatment with sulindac prevented NASH and subsequent HCC development. Intravital microscopy showed that liver colonization by platelets depended primarily on Kupffer cells at early and late stages of NASH, involving hyaluronan-CD44 binding. APT reduced intrahepatic platelet accumulation and the frequency of platelet-immune cell interaction, thereby limiting hepatic immune cell trafficking. Consequently, intrahepatic cytokine and chemokine release, macrovesicular steatosis and liver damage were attenuated. Platelet cargo, platelet adhesion and platelet activation but not platelet aggregation were identified as pivotal for NASH and subsequent hepatocarcinogenesis. In particular, platelet-derived GPIbα proved critical for development of NASH and subsequent HCC, independent of its reported cognate ligands vWF, P-selectin or Mac-1, offering a potential target against NASH.

Pubertal Status and Gonadal Functions in Obese Boys with Fatty Liver

BACKGROUND

In adult studies, obese subjects with nonalcoholic fatty liver disease (NAFLD) have been shown to have poor sperm quality, and lower testosterone and luteinizing hormone levels. The aim of this study was to investigate the pubertal status and gonadal functions in obese boys with NAFLD.

MATERIALS AND METHODS

The study included 119 obese and 78 nonobese age-matched adolescents. The obese boys were separated into two groups based on the presence (NAFLD group) or absence of liver steatosis with high transaminases (non-NAFLD group). The levels of serum AMH (anti-Mullerian hormone), inhibin B, gonadotropins, total testosterone, lipids, high-sensitivity C-reactive protein, fasting glucose, insulin levels, and aortic intima media thickness were measured in all subjects.

RESULTS

Of the total 197 children, 174 had reached puberty. There were no significant differences between the groups in respect of testicular sizes and the prevalence of pubertal status among the groups (84.3% of NAFLD vs. 70.6% of non-NAFLD vs. 98.7% of control subjects). No significant differences were found in respect of gonadotropins and AMH levels. Total testosterone levels in the NAFLD group were significantly lower than those of the non-NAFLD obese group (P < 0.001) and the control group (P < 0.001). Inhibin B levels were also significantly lower in all (NAFLD and non-NAFLD) obese groups compared to the control group (P = 0.008).

CONCLUSIONS

The results of the study demonstrated that diminished testosterone and inhibin B levels occur in pubertal obese boys with NAFLD. No significant differences were detected according to pubertal status, AMH levels, and testicular volumes in the age-matched groups.

Liver zonation in children with non-alcoholic fatty liver disease: Associations with dietary fructose and uric acid concentrations

BACKGROUND & AIMS

As dietary components are delivered directly to the periportal zone of the liver lobule, there is the potential for greater injury in this zone (zone 1) compared to the perivenous zone (zone 3). We investigated the associations between dietary fructose consumption and uric acid concentrations and differential zonal injury in periportal and perivenous zones.

METHODS

A total of 271 children's histological images were scored in 5 periportal and 5 perivenous zones for steatosis, ballooning, inflammation and fibrosis severity. Dietary fructose consumption (g/d) was assessed and uric acid measured in serum. Logistic regression was undertaken to test associations between both high fructose consumption and hyperuricaemia, and histological disease in periportal and perivenous zones.

RESULTS

Children with a mean age of 12.5 years were included in the study. Inflammation (mean ± SD) was increased in the periportal vs perivenous zones (0.78 ± 0.43 vs 0.41 ± 0.48, P = .041). There were non-significant trends towards greater steatosis, ballooning and fibrosis in the periportal zone. In the fully adjusted models, high fructose intake was associated with disease in both zones. Example for periportal and perivenous zones, respectively, steatosis 1.56 (1.12, 2.49) and 1.21 (1.09, 2.73); inflammation 4.29 (2.31, 5.88) and 3.69 (2.14, 4.56); and fibrosis 2.72 (1.43, 3.76) and 1.96 (1.24, 2.37). Hyperuricaemia (uric acid ≥5.9 mg/dL) was associated with inflammation in the periportal zone 1.71 (1.17, 2.35); and was associated with steatosis and fibrosis in both zones; for example, for periportal and perivenous zones, respectively, steatosis 2.98 (1.65, 3.23) and 1.14 (1.05, 1.99); and fibrosis, 2.65 (1.35, 2.99) and 1.31 (1.13, 2.17).

CONCLUSIONS

High fructose consumption is associated with disease severity in both lobular zones and hyperuricaemia may be associated with more severe disease in the periportal zone.

Psoralea corylifolia L. Attenuates Nonalcoholic Steatohepatitis in Juvenile Mouse

Psoralea corylifolia L. (PC) is a traditional Chinese herb used to treat yang deficiency of the spleen and kidney in pediatric disease. Recent studies have shown its liver protection and anti-oxidative effects. The aim of this study was to explore the effect and mechanism of PC on nonalcoholic steatohepatitis in juvenile mice. The juvenile mouse model of nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) was established by being fed a high-fat diet in maternal-offspring manner. PC granules were prepared and the quality was assessed. The main components were identified by high performance liquid chromatography. Then, different dosages of PC were administered for 6 weeks. Homeostatic model assessment of insulin resistance, plasma liver enzymes, hepatic morphology, hepatic superoxide anion, and triglyceride/total cholesterol levels were examined. The changes of nuclear factor-κB (NF-κB) activity phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) and protein kinase C-α (PKC-α)/nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase signaling pathways in hepatic tissues were also determined. Our data demonstrated that PC significantly improved liver dysfunction, liver triglyceride/total cholesterol accumulation and insulin resistance in juvenile NAFLD/NASH mice. PC also alleviated hepatic steatosis, inflammatory cell infiltration, and fibroplasia in the portal area. Additionally, PC inhibited the activation of NF-κB and the mRNA expression of inflammatory factors while enhancing PI3K/Akt signaling in hepatic tissues. PC could also reduce hepatic superoxide anion levels, and NADPH oxidase activity as well as p47^phox protein expression and PKCα activation in hepatic tissues. The results suggest that PC is effective in the treatment of NASH in juvenile mice. The mechanism may be related to the attenuation of hepatic oxidative stress through the PKC-α/NADPH oxidase signaling pathway.