The Contribution of the Adipose Tissue-Liver Axis in Pediatric Patients with Nonalcoholic Fatty Liver Disease after Laparoscopic Sleeve Gastrectomy.

OBJECTIVE: To evaluate the histopathologic modifications in liver and visceral adipose tissue (VAT), and to correlate these changes with clinical measures, adipokine production, and proinflammatory cytokines in a population of adolescents with obesity with nonalcoholic fatty liver disease (NAFLD) who underwent laparoscopic sleeve gastrectomy (LSG). STUDY DESIGN: Twenty adolescents with obesity who underwent LSG and with biopsy-proven NAFLD were included. Patients underwent clinical evaluation and blood tests at baseline and 1 year after the surgical procedure. Liver and VAT specimens were processed for routine histology, immunohistochemistry, and immunofluorescence. RESULTS: In adolescents with obesity and NAFLD, hepatic histologic alterations were uncorrelated with VAT inflammation. LSG induced in both liver and VAT tissue histopathology amelioration and macrophage profile modification that were correlated with body mass index and improvement in insulin resistance. The adipokine profile in liver and VAT was associated with weight loss and histologic improvement after LSG. Serum proinflammatory cytokines were correlated with liver and VAT histopathology and IL-1ß and IL-6 levels were independently predicted by liver necroinflammatory grade. CONCLUSIONS: This study suggests a unique adipose tissue/fatty liver crosstalk in pediatric patients. LSG induces a similar pattern of histologic improvement in the liver and in VAT. Besides VAT, our results strengthen the role of the liver in adipocytokine production and its contribution to systemic inflammation in pediatric patients with NAFLD.

The Number of Liver Galectin-3 Positive Cells Is Dually Correlated with NAFLD Severity in Children.

Non-alcoholic fatty liver disease (NAFLD) is a complex disease ranging from steatosis to non-alcoholic steatohepatitis (NASH). Galectin-3 (Gal-3), which is a ß-galactoside binding protein, has been associated with liver fibrosis, but its role in NAFLD remains elusive. We investigated the expression of Gal-3 in liver resident cells and its potential association with liver damage in 40 children with biopsy-proven NAFLD. We found that several liver cells expressed Gal-3. The number of total Gal-3 positive cells decreased with the severity of disease and the cells were correlated with the presence of steatosis and the diagnosis of NASH. CD68 macrophages expressed Gal-3 but the number CD68/Gal-3 positive cells was significantly reduced in patients diagnosed with steatosis and NASH. Triple CD68/CD206/Gal-3, which represented the subpopulation of M2 macrophages, were mainly present in patients without NASH, and clearly reduced in patients with steatosis and NASH. On the contrary, the number of α-smooth muscle actin (SMA)/Gal-3 positive cells increased with the severity of fibrosis in children with NAFLD. Our data demonstrated that the number of Gal-3 positive cells was associated with tissue damage in different ways, which suggests a dual role of this protein in the pathogenesis of pediatric NAFLD, even if the role of Gal-3 deserves further studies.

The Role of Genetic Predisposition, Programing During Fetal Life, Family Conditions, and Post-natal Diet in the Development of Pediatric Fatty Liver Disease.

OBJECTIVE: To evaluate, in patients with nonalcoholic fatty liver disease (NAFLD), the role of lifetime exposures associated with genetic predisposition, family history (parental obesity, economic income), programming during fetal life (gestational age, birthweight), being breastfed or not, and later biomarkers of dietary habits and lifestyle in the development of fibrosis. STUDY DESIGN: In total, 182 children with overweight/obesity diagnosed with NAFLD proven by biopsy results were enrolled in our study and evaluated for liver fibrosis. We estimated prevalence ORs of fibrosis according to genetics, parental obesity, occupational socioeconomic status (SES), birth weight, breastfeeding, fructose intake (indicator of junk food consumption), and vitamin D status (inflammatory indicator) using logistic regression models, adjusted for age and children's body mass. RESULTS: One hundred thirty-seven patients (75.3%) had liver fibrosis, and 45 patients (24.7%) did not have liver fibrosis. The ORs of fibrosis were significant (P < .05) for patatin like phospholipase domain-containing 3-GG genotype (OR 2.1), parental obesity (OR 2.9), not being breastfed (OR 3.1), vitamin D status (<20 mg/dL) (OR 1.24), and fructose consumption (OR 1.6 per 1 g/day increase), whereas a high SES maternal occupation was inversely associated with fibrosis (OR 0.30). CONCLUSIONS: Our results show independent roles of the patatin like phospholipase domain-containing 3 gene, parental obesity, maternal SES, and postnatal diet and lifestyle in the development of progressive liver disease secondary to NAFLD.

Laparoscopic Sleeve Gastrectomy Improves Nonalcoholic Fatty Liver Disease-Related Liver Damage in Adolescents by Reshaping Cellular Interactions and Hepatic Adipocytokine Production.

OBJECTIVES: To investigate whether the modulation of local cellular cross-talks and the modification of hepatic adipocytokine expression could mechanistically explain the improvement of liver histopathology after laparoscopic sleeve gastrectomy (LSG) in adolescents with nonalcoholic fatty liver disease (NAFLD). STUDY DESIGN: Twenty obese (body mass index of ≥35 kg/m2) adolescents who underwent LSG and with biopsy-proven NAFLD were included. At baseline (T0) and 1 year after treatment, patients underwent clinical evaluation, blood tests, and liver biopsy. Hepatic progenitor cells, hepatic stellate cells (HSCs), macrophages, and adipocytokines were evaluated by immunohistochemistry and immunofluorescence. RESULTS: Liver biopsy samples after LSG demonstrated a significant improvement of NAFLD Activity Score and fibrosis. Immunohistochemistry indicated a significant reduction of hepatocyte cell cycle arrest, ductular reaction, activated HSC, and macrophage number after LSG compared with T0. The activation state of HSC was accompanied by modification in the expression of the autophagy marker LC3. Hepatocyte expression of adiponectin was significant higher after LSG than into T0. Moreover, LSG caused decreased resistin expression in Sox9+ hepatic progenitor cells compared with T0. The number of S100A9+ macrophages was also reduced by LSG correlating with resistin expression. Finally, serum levels of proinflammatory cytokines significantly correlated with macrophages and activated HSC numbers. CONCLUSIONS: The histologic improvement induced by LSG is associated with the reduced activation of local cellular compartments (hepatic progenitor cells, HSCs, and macrophages), thus, strengthening the role of cellular interactions and hepatic adipocytokine production in the pathogenesis of NAFLD.

Nonalcoholic Fatty Liver Disease in Italian Children with Down Syndrome: Prevalence and Correlation with Obesity-Related Features.

OBJECTIVE: To assess the prevalence of overweight/obesity in a cohort of Italian children with Down syndrome (DS) and to investigate the correlation of both obesity and DS with nonalcoholic fatty liver disease (NAFLD). STUDY DESIGN: We enrolled 280 children with DS (age range 5-18 years), who were referred to the DS outpatient clinic of the Bambino Gesù Children's Hospital in Rome. For all children, we collected the clinical history and measured anthropometric variables. Eighty-four of 280 children with DS were selected to undergo liver ultrasound scanning to evaluate the presence of NAFLD. RESULTS: Italian children with DS exhibited a prevalence of 19.64% for overweight and 12.14% for obesity. The prevalence of NAFLD in nonobese (45%) and overweight/obese (82%) children with DS is greater than in the European pediatric nonobese (5.7%) or obese population (33%). Moreover, the severity of liver brightness on ultrasound scan correlated positively with body mass index, triglycerides, low-density lipoprotein-cholesterol, and leptin levels and negatively with adiponectin. CONCLUSIONS: We demonstrated that, independently from the obese phenotype, children with DS display a greater risk to develop NAFLD than the general pediatric population.

The Benefit of Sleeve Gastrectomy in Obese Adolescents on Nonalcoholic Steatohepatitis and Hepatic Fibrosis.

OBJECTIVE: To determine whether bariatric surgery is effective for the treatment of nonalcoholic steatohepatitis (NASH) in adolescence, we compared the efficacy of laparoscopic sleeve gastrectomy (LSG) with that of lifestyle intervention (nonsurgical weight loss [NSWL]) for NASH reversal in obese adolescents. STUDY DESIGN: Obese (body mass index ≥ 35 kg/m2) adolescents (13-17 years of age) with biopsy-proven NAFLD underwent LSG, lifestyle intervention plus intragastric weight loss devices (IGWLD), or only NSWL. At baseline and 1 year after treatment, patients underwent clinical and psychosocial evaluation, blood tests, liver biopsy, polysomnography, and 24-hour ambulatory blood pressure estimation. RESULTS: Twenty patients (21%) underwent LSG, 20 (21%) underwent IGWLD, and 53 (58%) received lifestyle intervention alone (NSWL). One year after treatment, patients who underwent LSG lost 21.5% of their baseline body weight, whereas patients who underwent IGWLD lost 3.4%, and patients who underwent NSWL increase 1.7%. In patients who underwent LSG, NASH reverted completely in all patients and hepatic fibrosis stage 2 disappeared in 18 patients (90%). After IGWLD, NASH reverted in 6 patients (24%) and fibrosis in 7 (37%). Patients who received the NSWL intervention did not improve significantly. Hypertension resolved in all patients who underwent LSG with preoperative hypertension (12/12) versus 50% (4/8) of the patients who underwent IGWLD (P = .02). The cohort-specific changes in impaired glucose metabolism were similar: 100% (9/9) of affected patients who underwent LSG versus 50% (1/2) of patients who underwent IGWLD (P = .02). LSG was also more affective in resolving dyslipidemia (55% [7/12] vs 26% [10/19]; P = .05) and sleep apnea (78% [2/9] vs 30% [11/20]; P = .001). CONCLUSION: LSG was more effective than lifestyle intervention, even when combined with intragastric devices, for reducing NASH and liver fibrosis in obese adolescents after 1 year of treatment.

Juvenile hemochromatosis associated with heterozygosity for novel hemojuvelin mutations and with unknown cofactors.

BACKGROUND & AIMS: Juvenile hemochromatosis (JH) is a rare autosomal recessive disorder characterized by severe early-onset iron overload, caused by mutations in hemojuvelin (HJV), hepcidin (HAMP), or a combination of genes regulating iron metabolism. Here we describe two JH cases associated with simple heterozygosity for novel HJV mutations and unknown genetic factors. Case 1: A 12 year-old male from Central Italy with beta-thalassemia trait, increased aminotransferases, ferritin 9035 ng/ml and transferrin saturation 84%, massive hepatocellular siderosis and hepatic bridging fibrosis. Case 2: A 12 year-old female from Northern Italy with ferritin 467 ng/ml, transferrin saturation 87-95%, and moderate hepatic iron overload. MATERIAL AND METHODS: Direct sequencing of hemochromatosis genes (HFE-TfR2-HJV-HAMP-FPN-1) was performed in the children and siblings. RESULTS: In case 1, we detected heterozygosity for a novel HJV mutation (g.3659_3660insG), which was inherited together with the beta thalassemia trait from the father, who (as well as the mother) had normal iron parameters. In case 2, we detected another novel HJV mutation (g.2297delC) in heterozygosity, which was inherited from the mother, affected by mild iron deficiency. The father had normal iron stores. Both mutations are frameshifts determining premature stop codons. No other disease causing variant was detected. CONCLUSION: Although beta-thalassemia trait was a possible cofactor of iron overload in case 1, iron overload cannot be explained by simple heterozygosity for HJV mutations in both cases. Other genetic factors should be investigated, and further studies are needed to understand genotype-phenotype correlations in JH.

Insulin-like growth factor-I and -II levels are associated with the progression of nonalcoholic fatty liver disease in obese children.

OBJECTIVE: To correlate circulating levels of insulin-like growth factor (IGF)-I, IGF-II, and IGF binding protein (IGFBP)-3 in a population of obese children with biopsy-proven nonalcoholic fatty liver disease (NAFLD) with clinical, biochemical, and histological features. STUDY DESIGN: We conducted a cross-sectional study at the Hepatometabolic Unit of the Bambino Gesù Children's Hospital, Rome, Italy. Obese children (42 girls and 57 boys) underwent liver biopsy, anthropometry, biochemical assessment, and IGF system evaluation. Serum concentrations of IGF-I, IGF-II, and IGFBP-3 were measured. The liver biopsy features of each case were graded according to the NAFLD Activity Scoring system. The degrees of steatosis, inflammation, ballooning, and fibrosis were calculated. RESULTS: Nonalcoholic steatohepatitis was diagnosed in 14/99 obese subjects. Stepwise regression analysis revealed that IGF-I was the major predictor of ballooning (ß = -0.463; P < .0001) and NAFLD activity score (ß = -0.457; P < .0001), IGF-I/IGFBP-3 ratio was the major predictor of liver inflammation (ß = -0.285; P = .005), and IGF-II was the major predictor of liver fibrosis (ß = 0.343; P < .005). CONCLUSION: Circulating levels of IGF-I and IGF-II are associated with the histological stages of NAFLD and may represent novel markers of liver damage progression in obese children.

Non-invasive assessment of fibrosis in non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in Western countries, and its prevalence is increasing worldwide. It currently affects approximately 30% of adults and 10% of children and adolescents. The resulting increase in the number of patients with NAFLD is expected to translate into increased numbers of patients with liver cirrhosis, and hepatocellular carcinoma. In this context, it is particularly important to identify patients at risk for progressive chronic liver disease. Currently, liver biopsy is the gold standard to diagnose non-alcoholic steatohepatitis (NASH) and to establish the presence and stage of fibrosis. Due to the remarkable increase in the prevalence of NAFLD and the concomitant efforts in developing novel therapies for patients with NASH, non-invasive, simple, reproducible, and reliable non-invasive methodologies are needed. This paper provides a concise overview of the role of non-invasive diagnostic tools for the determination of presence and extent of fibrosis in NAFLD patients, with particular emphasis on the methods currently available in clinical practice.

Association between type two diabetes and non-alcoholic fatty liver disease in youth.

In the last three decades prevalence of insulin related diseases has been growing worldwide with epidemic obesity, type 2 diabetes mellitus and non alcoholic fatty liver disease. In children such epidemics are particularly worrisome, since metabolic abnormalities track to the adulthood with significant implications for the health care system. Epidemiological studies support a close association between type 2 diabetes and fatty liver disease. We review the most recent epidemiological data on prevalence of both diseases in youth and their association.