Pediatric non-alcoholic fatty liver disease: current perspectives on diagnosis and management

Serum glutathione peroxidase is associated with nonalcoholic fatty liver disease in children and adolescents

Introduction

Background and aims: oxidative stress is an important factor in the pathophysiology of non-alcoholic fatty liver disease (NAFLD). This study aimed to compare the serum levels of malondialdehyde (MDA), glutathione peroxidase (GPx) and antioxidant micronutrients in children and adolescents with and without NAFLD. Methods: a cross-sectional study with patients between 8-18 years old, of both sexes. Diagnosis of NAFLD: presence of steatosis on ultrasound and absence of history of ethanol consumption and other liver diseases. Anthropometric measures, MDA, GPx, Interleukin-6, serum levels of vitamins A, C and E, selenium, zinc, and copper were evaluated. Results: eighty-nine children with mean age of 12 (3) years, 57.3 % female and 24 % with NAFLD were evaluated. Those with NAFLD had more frequent abdominal obesity (high waist-height ratio: 81.0 % x 48.5 %; p = 0.009). After logistic regression NAFLD was associated with high body mass index/age (p-adjusted = 0.021) and with reduced serum GPx (p-adjusted = 0.034). There was a positive correlation between MDA and copper (r = 0.288; p = 0.006), IL-6 (r = 0.357; p = 0.003) and a negative one with vitamin A (r = -0.270; p = 0.011). Conclusions: oxidative stress is present in children with NAFLD and non-invasive markers such as GPx and BMI can be used in clinical practice and help in the early screening of NAFLD.

Impact of Comorbid Polycystic Ovary Syndrome on Clinical and Laboratory Parameters in Female Adolescents with Metabolic Dysfunction-Associated Steatotic Liver Disease: A Cross-Sectional Study

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) and polycystic ovary syndrome (PCOS) share several pathophysiological mechanisms. While the prevalence of MASLD has been extensively studied in PCOS populations, the occurrence of PCOS among female adolescents with transient elastography (TE)-confirmed MASLD in pediatric hepatology settings remains poorly characterized. This cross-sectional study aims to address this knowledge gap and elucidate potential clinical and biochemical differences between female adolescents with MASLD and comorbid PCOS compared to those without PCOS. Methods: The study cohort included 45 female adolescents with TE-diagnosed MASLD. Comparative analyses of clinical and laboratory parameters were performed between those with (n = 19) and those without (n = 26) comorbid PCOS, diagnosed according to the Rotterdam criteria. Results: Adolescents with MASLD and comorbid PCOS exhibited significantly higher weight, lower height, and increased waist circumference compared to those without PCOS. Additionally, the prevalence of acanthosis nigricans was significantly higher in the PCOS group (68.4% versus 34.6%, p = 0.025). Regarding laboratory parameters, serum phosphorus levels and liver enzymes-including aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase-were significantly lower in adolescents with comorbid PCOS. However, no significant differences were observed in lipid profiles, glucose metabolism, or novel non-invasive biomarkers of MASLD. Conclusions: This study reveals distinct clinical and biochemical profiles in female adolescents with MASLD and comorbid PCOS compared to those without PCOS. These findings have the potential to inform and refine future screening protocols and diagnostic algorithms for these interrelated conditions, specifically tailored to pediatric hepatology settings.

Integrative metabolomics highlights gut microbiota metabolites as novel NAFLD-related candidate biomarkers in children

Altered gut microbiota and metabolites are important for non-alcoholic fatty liver disease (NAFLD) in children. We aimed to comprehensively examine the effects of gut metabolites on NAFLD progression. We performed integrative metabolomics (untargeted discovery and targeted validation) analysis of non-alcoholic fatty liver (NAFL), non-alcoholic steatohepatitis (NASH), and obesity in children. Fecal samples were collected from 75 subjects in the discovery cohort (25 NAFL, 25 NASH, and 25 obese control children) and 145 subjects in an independent validation cohort (53 NAFL, 39 NASH, and 53 obese control children). Among 2,491 metabolites, untargeted metabolomics revealed a complete NAFLD metabolic map containing 318 increased and 123 decreased metabolites. Then, machine learning selected 65 important metabolites that can distinguish the severity of the NAFLD. Furthermore, precision-targeted metabolomics selected 5 novel gut metabolites from 20 typical metabolites. The functionality of candidate metabolites was validated in hepatocyte cell lines. In the end, this study annotated two novel elevated pathogenic metabolites (dodecanoic acid and creatinine) and a relationship between depleted protective gut microbiota (Butyricicoccus and Alistipes), increased inflammation (IL-1β), lipid metabolism (TG), and liver function (ALT and AST). This study demonstrates the role of novel gut metabolites (dodecanoic acid and creatinine), as the fatty acid metabolism regulator contributing to NAFLD development through its influence on inflammation and liver function.

IMPORTANCE

Altered gut microbiota and metabolites are a major cause of non-alcoholic fatty liver disease (NAFLD) in children. This study demonstrated a complete gut metabolic map of children with NAFLD, containing 318 increased and 123 decreased metabolites by untargeted metabolomic. Multiple validation approaches (machine learning and targeted metabolomic) selected five novel gut metabolites for targeted metabolomics, which can distinguish NAFLD status and severity. The gut microbiota (Butyricicoccus and Alistipes) and metabolites (creatinine and dodecanoic acid) were novel biomarkers associated with impaired liver function and inflammation and validated by experiments of hepatocyte cell lines. The data provide a better understanding of the importance of gut microbiota and metabolite alterations in NAFLD, which implies that the altered gut microbiota and metabolites may represent a potential target to prevent NAFLD development.

Methods to Study Liver Disease Using Zebrafish Larvae

Liver disease affects millions of people worldwide, and the high morbidity and mortality is attributed in part to the paucity of treatment options. In many cases, liver injury self-resolves due to the remarkable regenerative capacity of the liver, but in cases when regeneration cannot compensate for the injury, inflammation and fibrosis occur, creating a setting for the emergence of liver cancer. Whole animal models are crucial for deciphering the basic biological underpinnings of liver biology and pathology and, importantly, for developing and testing new treatments for liver disease before it progresses to a terminal state. The cellular components and functions of the zebrafish liver are highly similar to mammals, and zebrafish develop many diseases that are observed in humans, including toxicant-induced liver injury, fatty liver, fibrosis, and cancer. Therefore, the widespread use of zebrafish larvae for studying the mechanisms of these pathologies and for developing potential treatments necessitates the optimization of experimental approaches to assess liver disease in this model. Here, we describe protocols using staining methods, imaging, and gene expression analysis to assess liver injury, fibrosis, and preneoplastic changes in the liver of larval zebrafish.

Biomarkers for Assessing Non-Alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus on Sodium-Glucose Cotransporter 2 Inhibitor Therapy

In the current modern era of unhealthy lifestyles, non-alcoholic fatty liver disease (NAFLD) is the most prevalent liver disease and has become a serious global health problem. To date, there is no approved pharmacotherapy for the treatment of NAFLD, and necessary lifestyle changes such as weight loss, diet, and exercise are usually not sufficient to manage this disease. Patients with type 2 diabetes mellitus (T2DM) have a significantly higher risk of developing NAFLD and vice versa. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are antidiabetic agents that have recently been approved for two other indications: chronic kidney disease and heart failure in diabetics and non-diabetics. They are also emerging as promising new agents for NAFLD treatment, as they have shown beneficial effects on hepatic inflammation, steatosis, and fibrosis. Studies in animals have reported favorable effects of SGLT2 inhibitors, and studies in patients also found positive effects on body mass index (BMI), insulin resistance, glucose levels, liver enzymes, apoptosis, and transcription factors. There are some theories regarding how SGLT2 inhibitors affect the liver, but the exact mechanism is not yet fully understood. Therefore, biomarkers to evaluate underlying mechanisms of action of SGLT2 inhibitors on the liver have now been scrutinized to assess their potential as a future in-label therapy for NAFLD. In addition, finding suitable non-invasive biomarkers could be helpful in clinical practice for the early detection of NAFLD in patients. This is crucial for a positive disease outcome. The aim of this review is to provide an overview of the most recent findings on the effects of SGLT2 inhibitors on NAFLD biomarkers and the potential of SGLT2 inhibitors to successfully treat NAFLD.

Analysis of risk factors for non-alcoholic fatty liver disease in hospitalized children with obesity before the late puberty stage

Objective

This study aimed to determine the clinical characteristics of obese pediatric non-alcoholic fatty liver disease (NAFLD) in central China and verify the applicability of some known risk factors for pediatric NAFLD before late puberty.

Methods

This was a retrospective case-control study. A total of 1,029 inpatients at Wuhan Children's Hospital before the late puberty stage were enrolled in the study, including 815 children with obesity (non-NAFLD group) and 214 children with obesity and NAFLD (NAFLD group) diagnosed by liver ultrasound. Subgroup analyses were performed according to sex and puberty. The anthropometric indices and laboratory test data of these 1,029 children were sorted. After intergroup comparison, a logistic regression model was used to determine the risk factors for pediatric NAFLD. Significant risk factors for NAFLD were further tested using receiver operating characteristic (ROC) curves to evaluate their ability to predict an early diagnosis of NAFLD.

Results

The NAFLD group had a mean age of 11.03 ± 1.66, with 11.18 ± 1.66 and 10.27 ± 1.45 years for male and female children, respectively (p < 0.05 and p < 0.01, respectively). Even subdivided by both sex and puberty, raised body mass index (BMI), homeostatic model-insulin resistance, triglycerides, alanine transaminase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (γ-GT) were still found in the non-NAFLD and NAFLD groups (p < 0.05 and p < 0.01, respectively). The results of logistic regression analysis showed that BMI (odds ratio [OR], 1.468;95% confidence interval [CI], 1.356-1.590; p<0.001) and ALT (OR, 1.073;95%CI, 1.060-1.087; P<0.001) were two most independent risk factors for NAFLD. The maximal OR for BMI was 1.721 (95% CI, 1.336-2.217). In the female group, the maximal OR of ALT was found to be 1.104 (95% CI, 1.061-1.148). Age and thyroid-stimulating hormone (TSH) and γ-GT levels were also risk factors, but they appeared only in some groups. The results of the ROC analysis showed that ALT was a better predictor of pediatric NAFLD than BMI. The maximum area under the ROC curve in six of the nine groups belongs to ALT.

Conclusions

BMI, ALT, and age are risk factors for NAFLD in children with obesity before late puberty. BMI had the greatest exposure risk for NAFLD, and ALT had the highest predictive value for the diagnosis of NAFLD. At the stratified level, for exposure risk, age was specific to the male sex, TSH was specific to the early puberty stage, and γ-GT was specific to the female sex plus the prepuberty stage. On a stratified level, for the female sex, even with age stratification, BMI rather than ALT has a better ability for the diagnosis of NAFLD.

Multi-Modality, Multi-Dimensional Characterization of Pediatric Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease is a multifaceted disease that progresses through multiple phases; it involves metabolic as well as structural changes. These alterations can be measured directly or indirectly through blood, non-invasive imaging, and/or tissue analyses. While some studies have evaluated the correlations between two sets of measurements (e.g., histopathology with cross-sectional imaging or blood biomarkers), the interrelationships, if any, among histopathology, clinical blood profiles, cross-sectional imaging, and metabolomics in a pediatric cohort remain unknown. We created a multiparametric clinical MRI-histopathologic NMR network map of pediatric NAFLD through multimodal correlation networks, in order to gain insight into how these different sets of measurements are related. We found that leptin and other blood markers were correlated with many other measurements; however, upon filtering out the blood biomarkers, the network was decomposed into three independent hubs centered around histopathological features, each with associated MRI and plasma metabolites. These multi-modality maps could serve as a framework for characterizing disease status and progression and could potentially guide medical interventions.

Prevalence of nonalcoholic fatty liver disease increased with type 2 diabetes mellitus in overweight/obese youth with polycystic ovary syndrome

OBJECTIVES

Polycystic ovary syndrome (PCOS) increases non-alcoholic fatty liver disease (NAFLD) risk and severity in adults, but data in adolescents with diverse backgrounds are limited. We evaluated NAFLD prevalence and characterized NAFLD risk factors in overweight/obese adolescents by PCOS status.

METHODS

Retrospective study of overweight (n=52)/obese (n=271) female adolescents (12-18 years old), evaluated clinically 2012-2020, was conducted comparing PCOS patients to age-matched non-PCOS controls. NAFLD was defined as ALT≥44U/L x2 and/or ≥80U/L x1, hepatic steatosis on imaging, or NAFLD on biopsy, in absence of other liver disease. Metabolic comorbidities were captured. Log-binomial regression models estimated prevalence risk ratios (PR).

RESULTS

NAFLD prevalence was 19.1 % in adolescents with PCOS (n=161), similar to those without (n=162) (16.8 %, p=0.6). Adolescents with PCOS were more likely to have insulin resistance, hypercholesterolemia, and higher triglycerides (p<0.05). Those with PCOS and concomitant type 2 diabetes (T2DM) did have increased NAFLD risk (PR 2.5, p=0.04), but those with PCOS without T2DM did not (PR 0.9, p=0.8). Adolescents with PCOS and NAFLD, compared to those with PCOS without NAFLD, had a higher prevalence of metabolic comorbidities including hypercholesterolemia (77 vs. 48 %), T2DM (29 vs. 8 %), and hypertriglyceridemia (65 vs. 37 %) (p<0.01).

CONCLUSIONS

Almost 1 in 5 overweight/obese female adolescents had NAFLD, but PCOS did not increase NAFLD risk in this diverse cohort. Among young women with PCOS, concomitant T2DM did increase the risk for NAFLD. Closer monitoring of obesity comorbidities in adolescents with PCOS is essential for optimizing health and merits updating current guidelines.

Nonalcoholic fatty liver disease in children with obesity- observations from one clinical centre in the Western Pomerania region

Nonalcoholic fatty liver disease (NAFLD) is a growing health problem in the pediatric population, due to the constantly increasing percentage of children with obesity. The objective of the study was to assess the occurrence of NAFLD based on ultrasound (USG) analysis and the use of alanine aminotransferase (ALT) in children with overweight and obesity depending on glucose tolerance. Medical records of 228 consecutive patients aged 2-18 years with overweight and obesity were reviewed retrospectively. Based on the oral glucose tolerance test children were divided into groups according to the severity of carbohydrate metabolism disorders. ALT, lipid parameters and insulin sensitivity indices HOMA, Matsuda and Quicki were analyzed. NAFLD was diagnosed (based on the USG) in 51 patients (23.61%) - the incidence in the impaired glucose tolerance (IGT) and type 2 diabetes (T2DM) group was significantly higher when compared to ones without glucose intolerance. Because of extreme values of metabolic parameters in TDM2 children being outliers, they were not considered in the statistical analysis of the study. 22 (11.58%) patients had elevated ALT values, of which 12 (54.55%) had hepatic steatosis features on ultrasound. 72.73% (n=32) patients with fatty liver features on USG had ALT values considered normal with cut-off point 42 U/l accepted in this study. Almost every fourth obese child in the study group presents features of fatty liver in ultrasound examination. Although ultrasound is not recommended by North American Society For Pediatric Gastroenterology, Hepatology &Nutrition(NASPGHAN) for the diagnosis of NAFLD in children, it allows identifying a high percentage of children with features of fatty liver. This percentage increases significantly in children with glucose intolerance.

Intermittent fasting and exercise therapy abates STZ-induced diabetotoxicity in rats through modulation of adipocytokines hormone, oxidative glucose metabolic, and glycolytic pathway

Diabetes is a global, costly, and growing public health issue. Intermittent fasting (IF) and exercise therapy have been shown to improve insulin sensitivity (IS) in large studies, although the underlying processes are still unknown. The goal of this study, which included both nondiabetic and diabetic rats, was to look at the mechanisms of intermittent fasting and exercise in the management of diabetotoxicity. The effects of starvation and honey on the oral glucose tolerance test, insulin tolerance test, adipocytokines, oxidative glucose metabolic enzymes, glycolytic enzymes, food intake, and body weight in rats with streptozotocin‐induced diabetes were also investigated. In the nondiabetic phase, rats were administered an oral regimen of distilled water (0.5 ml/rat), honey (1 g/kg body weight), and interventions with IF, and starvation for 4 weeks while in the diabetic phase, after STZ or citrate buffer injections, interventions with IF, exercise, starvation, and honey treatment began for 4 weeks. At all OGTT and ITT points, there was a substantial rise in glucose in the STZ group. Adipocytokines hormone, oxidative glucose metabolic enzymes, glycolytic enzymes, and body weight were all affected by STZ when compared to starvation and honey, however, IF and exercise significantly reduced these alterations. In diabetic rats, intermittent fasting and exercise enhanced serum adipocytokines levels. These findings imply that adipokines modulate glycolytic/nonmitochondrial enzymes and glucose metabolic/mitochondrial dehydrogenase to mediate the antidiabetic effects of intermittent fasting and exercise.

Intermittent fasting and exercise therapy abates STZ‐induced diabetotoxicity in rats through modulation of adipocytokines hormone, oxidative glucose metabolic, and glycolytic pathway.

Metabolic, behavioral health, and disordered eating comorbidities associated with obesity in pediatric patients: An Obesity Medical Association (OMA) Clinical Practice Statement 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) details metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children. This CPS will be followed by a companion CPS covering further comorbidities, including genetics and social consequences related to overweight and obesity. These CPSs are intended to provide clinicians with an overview of clinical practices applicable to children and adolescents with body mass indices greater than or equal to the 95th percentile for their ages, particularly those with adverse consequences resulting from increased body mass. The information in this CPS is based on scientific evidence, supported by the medical literature, and derived from the clinical experiences of members of the OMA.

Methods

The scientific information and clinical guidance in this CPS is based upon referenced evidence and derived from the clinical perspectives of the authors.

Results

This OMA statement details metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children. It provides clinical information regarding identifying and treating metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children over the 95th percentile of weight/height for age.

Conclusions

This OMA clinical practice statement details metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children and provides an overview of current recommendations. These recommendations lay out a roadmap to the improvement of the health of children and adolescents with obesity, especially those with metabolic, physiological, and psychological complications.

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

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

Schisandrin B ameliorates non-alcoholic liver disease through anti-inflammation activation in diabetic mice

Type 2 diabetes mellitus (T2DM) is a metabolic risk factor associated with non-alcoholic liver disease (NAFLD). Schisandrin B (Sch B) is a promising agent for NAFLD. However, the actions of Sch B on diabetes-associated NAFLD and the underlying mechanisms are not characterized. This study aimed to assess whether Sch B has beneficial effects on T2DM-associated NAFLD. Sch B (50 mg/kg, gavage) was administrated to C57BL/KSJ db/db mice for 2 weeks. Body weight, liver weight, blood glucose, and insulin resistance were measured. Serum lipid level and liver function were detected using the biochemistry analyzer. Quantitative Real-Time PCR assay was used to evaluate mRNA levers of lipid metabolism genes. Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling (TUNEL) staining was performed to measure apoptosis in the liver. Pathological analysis and immunohistochemistry assessment were used to analyze hepatic steatosis and inflammatory infiltration. Sch B supplementation significantly decrease body weight, related liver weight, blood glucose, and serum insulin, and improved insulin resistance in db/db mice. Sch B obviously corrected NAFLD phenotypes including lipid deposition, steatohepatitis, and high levels of hepatic enzymes and serum lipid. In addition, mRNA levels of Sterol response element-bind protein 1c (SREBP-1c), fatty acid synthetase (Fasn), and acetyl-CoA carboxylase (ACC) were markedly downregulated by Sch B treatment. TUNEL-positive cells were also decreased by Sch B. Furthermore, Sch B inhibited the Kupffer cells, IL-1β, and TNF-α infiltration to the liver. Sch B ameliorated insulin resistance and lipid accumulation under high glucose conditions, which was partly associated with its inhibition of apoptosis and anti-inflammatory actions.

Defining values for controlled attenuation parameter and liver stiffness in youth without liver disease

BACKGROUND

We aimed to determine the reference values to define an age-specific normal range of controlled attenuation parameter (CAP, a measure of liver steatosis) and liver stiffness measurement (LSM) values assessed by ultrasound-based transient elastography in adolescents without underlying liver disease.

METHODS

A total of 462 participants were included in this cross-sectional study using data from NHANES 2017-2018. LSM and CAP were carried out using the FibroScan® M-probe. Anthropometric, metabolic and hematological parameters were measured.

RESULTS

The median CAP was 199.0 dB/m (150.0-245.0 dB/m, 10th to 90th percentiles) and the median LSM was 4.7 kPa (3.4-6.3 kPa, 10th to 90th percentiles) for ages 12-19.9 years. Regression analyses show that the CAP and LSM were not positively correlated with age (boys CAP R² = 0.001, p = 0.576 and LSM R² = 0.012, p = 0.096; girls CAP R² = 0.011, p = 0.113 and LSM R² = 0.006, p = 0.236). Finally, CAP was positively associated with LSM in girls (β = 0.189, p = 0.005) but not in boys (β = -0.083, p = 0.202).

CONCLUSIONS

The reference values indicated here for LSM and CAP will help in the screening of adolescents between ages 12 and 19.9 years and might serve as a useful method for identifying those youth at high risk of nonalcoholic fatty liver disease.

IMPACT

The reference values indicated in this study for liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) will help in the screening of adolescents between ages 12 and 19.9 years in clinical practice. The cutoffs of LSM and CAP might serve as a useful method for identifying those youth at high risk of nonalcoholic fatty liver disease.

Probiotics for the improvement of metabolic profiles in patients with metabolic-associated fatty liver disease: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This meta-analysis of randomized controlled trials (RCTs) was conducted to assess the efficacy of probiotics in the treatment of metabolic-associated fatty liver disease (MAFLD) mainly in terms of liver function, glucose and lipid metabolism, and inflammation.

METHODS

RCTs were searched on PubMed, Web of Science, Embase, and the Cochrane Library until June 2022. A meta-analysis was performed on the therapeutic efficacy of probiotics on liver function, glucose and lipid metabolism, and inflammatory biomarkers by using RevMan 5.4 software.

RESULTS

A total of 772 patients from 15 studies were included in the analysis. The methodological quality varied across studies. We found that adding probiotic therapies could reduce the levels of alanine aminotransferase [mean difference (MD): -11.76 (-16.06, -7.46), p < 0.00001], aspartate aminotransferase (MD: -9.08 (-13.60, -4.56), p < 0.0001], γ-glutamyltransferase [MD: -5.67 (-6.80, -4.54), p < 0.00001] and homeostasis model assessment-insulin resistance [MD: -0.62 (-1.08, -0.15), p = 0.01], in patients with MAFLD compared with those in control individuals. However, there was no statistically significant improvement in the levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, C-reactive protein and tumor necrosis factor α among patients with MAFLD. Subgroup analyses showed that other key factors, such as age, participants' baseline body mass index, and the duration of intervention, may influence probiotic therapy outcomes.

CONCLUSION

There is promising evidence that probiotic supplementation can reduce liver enzyme levels and regulate glycometabolism in patients with MAFLD. Further rigorous and long-term trials exploring these novel therapeutic perspectives are warranted to confirm these results.

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.

Investigation of Thiol/Disulfide Balance in Obese Rats with Non-Alcoholic Fatty Liver Disease

PURPOSE

Due to the increasing prevalence of obesity worldwide, non-alcoholic fatty liver disease (NAFLD) has reached epidemic dimensions over time. NAFLD is the most common cause of childhood chronic liver disease. There is a relationship between NAFLD and oxidative stress. This study aims to investigate the changes in thiol/disulfide homeostasis parameters to determine the oxidant/antioxidant balance in obese rats with diet-induced NAFLD and healthy rats.

METHODS

Twelve Wistar albino rats were used in this study. Experimentally produced NAFLD obese rats (n=6) and healthy rats were compared. Experimental NAFLD model was created with a special fatty liver diet (Altromin® C1063, Fatty Liver Diet, Exclusivet, Lage, Germany). The biochemical and histopathological features of the groups, as well as serum thiol/disulfide homeostasis parameters, were analyzed and compared.

RESULTS

In the experimentally induced NAFLD rat model, they gained more weight than the control group. Steatosis (at least grade 2) occurred in all rats fed with special fatty liver diet for 12 weeks. Histopathologically, no high-grade inflammation was observed in rats with experimental NAFLD after feeding a diet for 12 weeks. Results revealed that aspartate transaminase and alanine transaminase levels were high, albumin levels were low, oxidant stress parameters increased, and antioxidant thiol groups decreased.

CONCLUSION

Experimental NAFLD is characterized by increased oxidant stress accompanying fatty tissue in the liver. Analysis of thiol/disulfide homeostasis parameters in NAFLD can be used in further studies to develop effective treatment options.

Neutral sphingomyelinase-2 and cardiometabolic diseases

Sphingolipids, in particular ceramides, play vital role in pathophysiological processes linked to metabolic syndrome, with implications in the development of insulin resistance, pancreatic ß-cell dysfunction, type 2 diabetes, atherosclerosis, inflammation, nonalcoholic steatohepatitis, and cancer. Ceramides are produced by the hydrolysis of sphingomyelin, catalyzed by different sphingomyelinases, including neutral sphingomyelinase 2 (nSMase2), whose dysregulation appears to underlie many of the inflammation-related pathologies. In this review, we discuss the current knowledge on the biochemistry of nSMase2 and ceramide production and its regulation by inflammatory cytokines, with particular reference to cardiometabolic diseases. nSMase2 contribution to pathogenic processes appears to involve cyclical feed-forward interaction with proinflammatory cytokines, such as TNF-α and IL-1ß, which activate nSMase2 and the production of ceramides, that in turn triggers the synthesis and release of inflammatory cytokines. We elaborate these pathogenic interactions at the molecular level and discuss the potential therapeutic benefits of inhibiting nSMase2 against inflammation-driven cardiometabolic diseases.

Role of Leptin in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD), which affects about a quarter of the global population, poses a substantial health and economic burden in all countries, yet there is no approved pharmacotherapy to treat this entity, nor well-established strategies for its diagnosis. Its prevalence has been rapidly driven by increased physical inactivity, in addition to excessive calorie intake compared to energy expenditure, affecting both adults and children. The increase in the number of cases, together with the higher morbimortality that this disease entails with respect to the general population, makes NAFLD a serious public health problem. Closely related to the development of this disease, there is a hormone derived from adipocytes, leptin, which is involved in energy homeostasis and lipid metabolism. Numerous studies have verified the relationship between persistent hyperleptinemia and the development of steatosis, fibrinogenesis and liver carcinogenesis. Therefore, further studies of the role of leptin in the NAFLD spectrum could represent an advance in the management of this set of diseases.

Nonalcoholic Fatty Liver Disease: Focus on New Biomarkers and Lifestyle Interventions

Nonalcoholic fatty liver disease (NAFLD) is considered a hepatic manifestation of metabolic syndrome, characterized from pathological changes in lipid and carbohydrate metabolism. Its main characteristics are excessive lipid accumulation and oxidative stress, which create a lipotoxic environment in hepatocytes leading to liver injury. Recently, many studies have focused on the identification of the genetic and epigenetic modifications that also contribute to NAFLD pathogenesis and their prognostic implications. The present review is aimed to discuss on cellular and metabolic alterations associated with NAFLD, which can be helpful to identify new noninvasive biomarkers. The identification of accumulated lipids in the cell membranes, as well as circulating cytokeratins and exosomes, provides new insights in understanding of NAFLD. This review also suggests that lifestyle modifications remain the main prevention and/or treatment for NAFLD.

MAFLD in Obese Children: A Challenging Definition

BACKGROUND

Recently, the new definition of Metabolic (dysfunction) associated fatty liver disease (MAFLD) has gained remarkable scientific interest. We aimed to evaluate the effectiveness of MAFLD definition in selecting obese children at higher cardiovascular risk.

METHODS

A total of 954 obese children and adolescents was retrospectively enrolled. Clinical, biochemical, and metabolic evaluations were performed. Hepatic steatosis was assessed by liver ultrasound. According to the metabolic status, the population was divided in three groups. Group 1 included obese patients without both non-alcoholic fatty liver disease (NAFLD) and metabolic dysregulation; group 2 included patients with obesity and NAFLD (then encompassing one MAFLD criterion); group 3 included patients with obesity, NAFLD and evidence of metabolic dysregulation (then encompassing more than 1 MAFLD criteria).

RESULTS

Patients of Group 3 showed a worse cardiometabolic profile, as also proven by the higher percentage of prediabetes (defined as the presence of impaired fasting glucose or impaired glucose tolerance) compared to other groups (p = 0.001).

CONCLUSIONS

MAFLD criteria in obese children seem to be less accurate in identifying patients having an intrinsic higher cardiometabolic risk. This suggests the need for a more accurate definition in the context of pediatric obesity.

Pulmonary Manifestations of Gastrointestinal, Pancreatic, and Liver Diseases in Children

Pulmonary manifestations of gastrointestinal (GI) diseases are often subtle, and underlying disease may precede overt symptoms. A high index of suspicion and a low threshold for consultation with a pediatric pulmonologist is warranted in common GI conditions. This article outlines the pulmonary manifestations of different GI, pancreatic, and liver diseases in children, including gastroesophageal reflux disease, inflammatory bowel disease, pancreatitis, alpha1-antitrypsin deficiency, nonalcoholic fatty liver disease, and complications of chronic liver disease (hepatopulmonary syndrome and portopulmonary hypertension).

Bifidobacterium breve CNCM I-4035, Lactobacillus paracasei CNCM I-4034 and Lactobacillus rhamnosus CNCM I-4036 Modulate Macrophage Gene Expression and Ameliorate Damage Markers in the Liver of Zucker-Lepr fa/fa Rats

Non-alcoholic fatty liver disease (NAFLD) has reached pandemic proportions worldwide. We have previously reported that the probiotic strains Bifidobacterium breve CNCM I-4035, Lactobacillus paracasei CNCM I-4034 and Lactobacillus rhamnosus CNCM I-4036 exert anti-inflammatory effects in the intestine of Zucker-Lepr fa/fa rats. In this work, we focused on their hepatic effects. M1 macrophages are related to inflammation and NAFLD pathogenesis, whereas M2 macrophages release anti-inflammatory mediators. We evaluated the effects of these 3 strains on macrophage polarization, inflammation and liver damage of Zucker-Lepr fa/fa rats. The animals received either a placebo or 1010 CFU of probiotics orally for 30 days. Nos2 and Cd86 mRNA levels were determined as markers of M1 macrophages, and Cd163 and Arg1 as M2 markers, respectively, by qRT-PCR. Liver damage was determined by lipid peroxidation, leukocyte infiltration and myeloperoxidase activity. We evaluated a panoply of circulating chemokines, the hepatic ratio P-Akt/Akt, NF-kB and P-NF-kB protein levels. All 3 probiotic strains modulated macrophage polarization in liver and circulating levels of inflammation-related mediators. L. paracasei CNCM I-4034 increased the ratio P-Akt/Akt and NF-kB protein levels. B. breve CNCM I-4035, L. paracasei CNCM I-4034 and L. rhamnosus CNCM I-4036 decreased both pro-inflammatory macrophage gene expression and leukocyte infiltration in the liver.

Possible Hepatoprotective Effect of Tocotrienol-Rich Fraction Vitamin E in Non-alcoholic Fatty Liver Disease in Obese Children and Adolescents

Obesity has become a worldwide health concern among the pediatric population. The prevalence of non-alcoholic fatty liver disease (NAFLD) is growing rapidly, alongside the high prevalence of obesity. NAFLD refers to a multifactorial disorder that includes simple steatosis to non-alcoholic steatohepatitis (NASH) with or devoid of fibrosis. NAFLD is regarded as a systemic disorder that influences glucose, lipid, and energy metabolism with hepatic manifestations. A sedentary lifestyle and poor choice of food remain the major contributors to the disease. Prompt and timely diagnosis of NAFLD among overweight children is crucial to prevent the progression of the condition. Yet, there has been no approved pharmacological treatment for NAFLD in adults or children. As indicated by clinical evidence, lifestyle modification plays a vital role as a primary form of therapy for managing and treating NAFLD. Emphasis is on the significance of caloric restriction, particularly macronutrients (fats, carbohydrates, and proteins) in altering the disease consequences. A growing number of studies are now focusing on establishing a link between vitamins and NAFLD. Different types of vitamin supplements have been shown to be effective in treating NAFLD. In this review, we elaborate on the potential role of vitamin E with a high content of tocotrienol as a therapeutic alternative in treating NAFLD in obese children.

The pharmacological treatment of nonalcoholic fatty liver disease in children

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in childhood/adolescence. It comprises a broad spectrum of liver disease severity ranging from simple steatosis to steatohepatitis and fibrosis. To date lifestyle modifications, diet and physical activity represent the main option for the management of pediatric NAFLD, but numerous treatments classified depending on the mechanism of action, have been introduced. In keeping with, bariatric surgery, insulin sensitizers, antioxidants, probiotic and dietary supplementations have been evaluated in pediatric clinical trials.

AREAS COVERED

This review describes, after a search in PubMed/MEDLINE database, the current pediatric NAFLD non-pharmacological and pharmacological treatments and their effects on biochemical and histological features. We report not only the efficacy of the diet coupled with regular exercise but also advantages of the pharmacological treatments used in combination with lifestyle interventions in pediatric NAFLD.

EXPERT OPINION

Since pharmacological and non-pharmacological interventions have demonstrated variable effects in pediatric NAFLD, it is clear that safe and specific and efficient therapeutic strategies have not yet been identified. Therefore, large and long-term clinical trials in children are needed to find a way to reverse the liver tissue damage and the NAFLD-related long-term morbidity and mortality.

Crosstalk Between Liver Macrophages and Surrounding Cells in Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH), the advanced stage of nonalcoholic fatty liver disease (NAFLD), is emerging as a leading cause of progressive liver fibrosis and end-stage liver disease. Liver macrophages, mainly composed of Kupffer cells (KCs) and monocyte-derived macrophages (MoMFs), play a vital role in NASH progression and regression. Recent advances suggest that cell–cell communication is a fundamental feature of hepatic microenvironment. The reprogramming of cell–cell signaling between macrophages and surrounding cells contributes to the pathogenesis of NASH. In this review, we summarize the current knowledge of NASH regarding the composition of liver macrophages and their communication with surrounding cells, which are composed of hepatocytes, hepatic stellate cells (HSCs), liver sinusoidal endothelial cells (LSECs) and other immune cells. We also discuss the potential therapeutic strategies based on the level of macrophages.