Development and validation of pFIB scores for exclusion of significant liver fibrosis in pediatric MASLD.

BACKGROUND AND AIMS: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent pediatric liver disease, yet accurate risk scores for referral of children/adolescents with suspected clinically significant liver fibrosis are currently lacking. APPROACH AND RESULTS: Clinical and biochemical variables were collected in a prospective cohort of 327 children and adolescents with severe obesity, in whom liver fibrosis was evaluated by transient elastography. Logistic regression was performed to establish continuous (pFIB-c) and simplified (pFIB-6) diagnostic scores that accurately exclude significant (≥F2) fibrosis. Performance for each was compared to established noninvve fibrosis scores. These scores were validated in elastography (n=504) and multiple biopsy-proven MASLD (n=261) cohorts. Patient sex, ethnicity, weight z-score, homeostatic model assessment of insulin resistance index, ALT, and presence of hypertension were included in the scores. The pFIB-c and pFIB-6 exhibited good discriminatory capacity (c-statistic of 0.839 and 0.826), outperforming existing indices. Negative predictive values were >90% for both scores in the derivation and elastography validation cohorts. Performance in the histological cohorts varied (AUROCs for the pFIB-c between 0.710 and 0.770), as the scores were less accurate when applied to populations in tertiary referral centers characterized by a high prevalence of significant fibrosis and high ALT levels. CONCLUSIONS: Analyzing several cohorts totaling approximately 1100 children and adolescents, we developed novel risk scores incorporating readily available clinical variables. In accordance with the aim of excluding pediatric MASLD-associated fibrosis, the scores performed better in nonselected cohorts of children and adolescents living with obesity than in patients referred to tertiary liver units.

Noninvasive scores are poorly predictive of histological fibrosis in paediatric fatty liver disease.

OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children. Roughly a quarter of paediatric patients with NAFLD develop nonalcoholic steatohepatitis and fibrosis. Here, we evaluated the diagnostic accuracy of previously published noninvasive fibrosis scores to predict liver fibrosis in a large European cohort of paediatric patients with NAFLD. METHODS: The 457 patients with biopsy-proven NAFLD from 10 specialized centers were included. We assessed diagnostic accuracy for the prediction of any (F ≥ 1), moderate (F ≥ 2) or advanced (F ≥ 3) fibrosis for the AST/platelet ratio (APRI), Fibrosis 4 score (FIB-4), paediatric NAFLD fibrosis score (PNFS) and paediatric NAFLD fibrosis index (PNFI). RESULTS: Patients covered the full spectrum of fibrosis (F0: n = 103; F1: n = 230; F2: n = 78; F3: n = 44; F4: n = 2). None of the scores were able to accurately distinguish the presence of any fibrosis from no fibrosis. For the detection of moderate fibrosis, area under the receiver operating characteristic curve (AUROC) were: APRI: 0.697, FIB-4: 0.663, PNFI: 0.515, PNFS: 0.665, while for detection of advanced fibrosis AUROCs were: APRI: 0.759, FIB-4: 0.611, PNFI: 0.521, PNFS: 0.712. Fibrosis scores showed no diagnostic benefit over using ALT ≤ 50/ > 50 IU/L as a cut-off. CONCLUSIONS: Established fibrosis scores lack diagnostic accuracy to replace liver biopsy for staging of fibrosis, giving similar results as compared to using ALT alone. New diagnostic tools are needed for Noninvasive risk-stratification in paediatric NAFLD.

Alterations of Central Liver Metabolism of Pediatric Patients with Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and is associated with overweight and insulin resistance (IR). Almost nothing is known about in vivo alterations of liver metabolism in NAFLD, especially in the early stages of non-alcoholic steatohepatitis (NASH). Here, we used a complex mathematical model of liver metabolism to quantify the central hepatic metabolic functions of 71 children with biopsy-proven NAFLD. For each patient, a personalized model variant was generated based on enzyme abundances determined by mass spectroscopy. Our analysis revealed statistically significant alterations in the hepatic carbohydrate, lipid, and ammonia metabolism, which increased with the degree of obesity and severity of NAFLD. Histologic features of NASH and IR displayed opposing associations with changes in carbohydrate and lipid metabolism but synergistically decreased urea synthesis in favor of the increased release of glutamine, a driver of liver fibrosis. Taken together, our study reveals already significant alterations in the NASH liver of pediatric patients, which, however, are differently modulated by the simultaneous presence of IR.

Hepatocyte-specific NRF2 activation controls fibrogenesis and carcinogenesis in steatohepatitis.

BACKGROUND & AIMS: In chronic liver diseases, inflammation induces oxidative stress and thus may contribute to the progression of liver injury, fibrosis, and carcinogenesis. The KEAP1/NRF2 axis is a major regulator of cellular redox balance. In the present study, we investigated whether the KEAP1/NRF2 system is involved in liver disease progression in humans and mice. METHODS: The clinical relevance of oxidative stress was investigated by liver RNA sequencing in a well-characterized cohort of patients with non-alcoholic fatty liver disease (n = 63) and correlated with histological and clinical parameters. For functional analysis, hepatocyte-specific Nemo knockout (NEMOΔhepa) mice were crossed with hepatocyte-specific Keap1 knockout (KEAP1Δhepa) mice. RESULTS: Immunohistochemical analysis of human liver sections showed increased oxidative stress and high NRF2 expression in patients with chronic liver disease. RNA sequencing of liver samples in a human pediatric NAFLD cohort revealed a significant increase of NRF2 activation correlating with the grade of inflammation, but not with the grade of steatosis, which could be confirmed in a second adult NASH cohort. In mice, microarray analysis revealed that Keap1 deletion induces NRF2 target genes involved in glutathione metabolism and xenobiotic stress (e.g., Nqo1). Furthermore, deficiency of one of the most important antioxidants, glutathione (GSH), in NEMOΔhepa livers was rescued after deleting Keap1. As a consequence, NEMOΔhepa/KEAP1Δhepa livers showed reduced apoptosis compared to NEMOΔhepa livers as well as a dramatic downregulation of genes involved in cell cycle regulation and DNA replication. Consequently, NEMOΔhepa/KEAP1Δhepa compared to NEMOΔhepa livers displayed decreased fibrogenesis, lower tumor incidence, reduced tumor number, and decreased tumor size. CONCLUSIONS: NRF2 activation in patients with non-alcoholic steatohepatitis correlates with the grade of inflammation, but not steatosis. Functional analysis in mice demonstrated that NRF2 activation in chronic liver disease is protective by ameliorating fibrogenesis, initiation and progression of hepatocellular carcinogenesis. LAY SUMMARY: The KEAP1 (Kelch-like ECH-associated protein-1)/NRF2 (erythroid 2-related factor 2) axis has a major role in regulating cellular redox balance. Herein, we show that NRF2 activity correlates with the grade of inflammation in patients with non-alcoholic steatohepatitis. Functional studies in mice actually show that NRF2 activation, resulting from KEAP1 deletion, protects against fibrosis and cancer.

rs641738C>T near MBOAT7 is associated with liver fat, ALT and fibrosis in NAFLD: A meta-analysis.

BACKGROUND & AIMS: A common genetic variant near MBOAT7 (rs641738C>T) has been previously associated with hepatic fat and advanced histology in NAFLD; however, these findings have not been consistently replicated in the literature. We aimed to establish whether rs641738C>T is a risk factor across the spectrum of NAFLD and to characterise its role in the regulation of related metabolic phenotypes through a meta-analysis. METHODS: We performed a meta-analysis of studies with data on the association between rs641738C>T genotype and liver fat, NAFLD histology, and serum alanine aminotransferase (ALT), lipids or insulin. These included directly genotyped studies and population-level data from genome-wide association studies (GWAS). We performed a random effects meta-analysis using recessive, additive and dominant genetic models. RESULTS: Data from 1,066,175 participants (9,688 with liver biopsies) across 42 studies were included in the meta-analysis. rs641738C>T was associated with higher liver fat on CT/MRI (+0.03 standard deviations [95% CI 0.02-0.05], pz = 4.8×10-5) and diagnosis of NAFLD (odds ratio [OR] 1.17 [95% CI 1.05-1.3], pz = 0.003) in Caucasian adults. The variant was also positively associated with presence of advanced fibrosis (OR 1.22 [95% CI 1.03-1.45], pz = 0.021) in Caucasian adults using a recessive model of inheritance (CC + CT vs. TT). Meta-analysis of data from previous GWAS found the variant to be associated with higher ALT (pz = 0.002) and lower serum triglycerides (pz = 1.5×10-4). rs641738C>T was not associated with fasting insulin and no effect was observed in children with NAFLD. CONCLUSIONS: Our study validates rs641738C>T near MBOAT7 as a risk factor for the presence and severity of NAFLD in individuals of European descent. LAY SUMMARY: Fatty liver disease is a common condition where fat builds up in the liver, which can cause liver inflammation and scarring (including 'cirrhosis'). It is closely linked to obesity and diabetes, but some genes are also thought to be important. We did this study to see whether one specific change ('variant') in one gene ('MBOAT7') was linked to fatty liver disease. We took data from over 40 published studies and found that this variant near MBOAT7 is linked to more severe fatty liver disease. This means that drugs designed to work on MBOAT7 could be useful for treating fatty liver disease.

Do Children With Functional Abdominal Pain Benefit More From a Pain-Specific Cognitive-Behavioral Intervention Than From an Unspecific Attention Control Intervention? Results of a Randomized Controlled Trial.

INTRODUCTION: We aimed to compare the efficacy of cognitive-behavioral therapy (CBT) among children with functional abdominal pain with an attention control (AC), hypothesizing the superiority of CBT group intervention regarding pain intensity (primary outcome), pain duration and frequency (further primary outcomes), functional disability, and quality of life and coping strategies (key secondary outcomes). METHODS: We conducted a prospective, multicenter, randomized controlled efficacy trial (RCT) with 4 time points (before intervention, after intervention, 3-month follow-up, and 12-month follow-up). One hundred twenty-seven children aged 7-12 years were randomized to either the CBT (n = 63; 55.6% girls) or the AC (n = 64; 57.8% girls). RESULTS: Primary endpoint analysis of the logarithmized area under the pain intensity curve showed no significant difference between groups (mean reduction = 49.04%, 95% confidence interval [CI] -19.98%-78.36%). Treatment success rates were comparable (adjusted odds ratio = 0.53, 95% CI 0.21-1.34, number needed to treat = 16). However, time trend analyses over the course of 1 year revealed a significantly greater reduction in pain intensity (40.9%, 95% CI 2.7%-64.1%) and pain duration (43.6%, 95% CI 6.2%-66.1%) in the CBT compared with the AC, but not in pain frequency per day (1.2, 95% CI -2.7 to 5.2). In the long term, children in the CBT benefitted slightly more than those in the AC with respect to functional disability, quality of life, and coping strategies. DISCUSSION: Both interventions were effective, which underlines the role of time and attention for treatment efficacy. However, in the longer term, CBT yielded more favorable results.

Genetic determinants of steatosis and fibrosis progression in paediatric non-alcoholic fatty liver disease.

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and adolescents today. In comparison with adult disease, paediatric NAFLD may show a periportal localization, which is associated with advanced fibrosis. This study aimed to assess the role of genetic risk variants for histological disease pattern and severity in childhood NAFLD. METHODS: We studied 14 single nucleotide polymorphisms (SNP) in a cohort of 70 adolescents with biopsy-proven NAFLD. Genotype was compared to an adult control cohort (n = 200) and analysed in relation to histological disease severity and liver tissue proteomics. RESULTS: Three of the 14 SNPs were significantly associated with paediatric NAFLD after FDR adjustment, rs738409 (PNPLA3, P = 2.80 × 10-06 ), rs1044498 (ENPP1, P = 0.0091) and rs780094 (GCKR, P = 0.0281). The severity of steatosis was critically associated with rs738409 (OR=3.25; 95% CI: 1.72-6.52, FDR-adjusted P = 0.0070). The strongest variants associated with severity of fibrosis were rs1260326, rs780094 (both GCKR) and rs659366 (UCP2). PNPLA3 was associated with a portal pattern of steatosis, inflammation and fibrosis. Proteome profiling revealed decreasing levels of GCKR protein with increasing carriage of the rs1260326/rs780094 minor alleles and downregulation of the retinol pathway in rs738409 G/G carriers. Computational metabolic modelling highlighted functional relevance of PNPLA3, GCKR and UCP2 for NAFLD development. CONCLUSIONS: This study provides evidence for the role of PNPLA3 as a determinant of portal NAFLD localization and severity of portal fibrosis in children and adolescents, the risk variant being associated with an impaired hepatic retinol metabolism.