Liver Steatosis: A Marker of Metabolic Risk in Children

Role of metabolic dysfunction-associated steatotic liver disease and of its genetics on kidney function in childhood obesity

OBJECTIVES

Evidence linked metabolic associated steatotic liver disease (MASLD) to kidney damage with the potential contribution of the I148M variant of the Patatin-like phospholipase containing domain 3 (PNPLA3) gene. We aimed at investigating the relationship of MASLD and of its genetics with kidney function in children with obesity.

METHODS

A comprehensive evaluation including genotyping for the I148M PNPLA3 polymorphism was performed in 1037 children with obesity. Fatty liver (FL) was assessed by liver ultrasound. According to MASLD criteria, subjects with obesity but without FL were included in group 1, while patients with obesity and FL (encompassing one MASLD criterion) were clustered into group 2. Group 3 included patients with obesity, FL, and metabolic dysregulation (encompassing >1 MASLD criterion).

RESULTS

Alanine transaminase levels significantly increased while estimated glomerular filtration rate (eGFR) significantly reduced from group 1 to 3. Group 3 showed a higher percentage of carriers of the I148M allele of the PNPLA3 gene compared to other groups (p < 0.0001). Carriers of group 2 and of group 3 showed reduced eGFR levels than noncarriers of group 2 (p = 0.04) and of group 3 (p = 0.02), respectively. A general linear model for eGFR variance in the study population showed an inverse association of eGFR with both MASLD and PNPLA3 genotypes (p = 0.011 and p = 0.02, respectively). An inverse association of eGFR with MASLD was also confirmed only in carriers (p = 0.006).

CONCLUSIONS

The coexistence of more than 1 MASLD criterion in children with obesity seems to adversely affect kidney function. The PNPLA3 I148M allele further impacts on this association.

The Association of the HEPAKID Index with Insulin Sensitivity Index in Obese Adolescents with Metabolic Syndrome

Objective: The HEPAKID index, a novel diagnostic tool with a sensitivity of 82% and specificity of 62% for detecting nonalcoholic fatty liver disease in obese adolescents. Our study aimed to explore the potential relationship between the HEPAKID index and risk factors contributing to the development of cardiovascular disease in obese adolescents with metabolic syndrome. Methods: This prospective cross-sectional study, conducted at two medical centers from December 2023 to March 2024, included 208 obese adolescents, with a median age of 14.5 years and an average body mass index (BMI) of 30.57 kg/m2. Results: Elevated HEPAKID index values were found in obese adolescents with metabolic syndrome, showing positive associations with BMI, waist and hip circumferences, alanine aminotransferase level, fasting insulin, and homeostasis model assessment for insulin resistance. In those with metabolic syndrome, waist circumference (WC) and homeostasis model assessment for insulin resistance were significant independent variables linked to the HEPAKID index, while WC was the sole influencer in the nonmetabolic syndrome group. Multivariate logistic regression highlighted systolic and diastolic blood pressures, triglycerides, high-density lipoprotein cholesterol, and the HEPAKID index as reliable predictors of metabolic syndrome. A predictive cutoff value of 60.84 for the HEPAKID index showed 61.7% sensitivity and 59.1% specificity in identifying metabolic syndrome. Conclusions: Our study highlighted the potential value of the HEPAKID index in combination with other clinical parameters for predicting metabolic syndrome in obese adolescents, underscoring its role as a valuable screening tool. Furthermore, our findings revealed a correlation between the HEPAKID index and insulin sensitivity in this high-risk population.

Effects of multidisciplinary therapy on energy balance, inflammation, and metabolic diseases in adolescents with obesity: A narrative review

Obesity is a consequence of multiple factors, including genetics, lifestyle and nutritional choices, physical activity, sleep duration, screen time, and mood disorders. These behavioral elements can impair the regulation of energy balance and obesity management that link obesity to a constellation of chronic conditions that lead to a high prevalence of cardiometabolic risk factors, metabolic syndrome, and nonalcoholic fatty liver disease. Multidisciplinary therapy is defined as an approach delivered by a multidisciplinary-trained health team covering at least two components of behavior, physical activity/exercise, dietary habits, and/or psychological counseling associated with clinical interventions. This narrative review summarizes the effects of multidisciplinary therapy on neuroendocrine regulation of energy balance, inflammatory biomarkers, cardiometabolic risk factors, metabolic syndrome, nonalcoholic fatty liver diseases, behavior, and quality of life. We found that multidisciplinary therapy, including medical, nutritional, exercise, and behavioral counseling, and/or education, was useful for addressing outcomes such as visceral adiposity, neuroendocrine regulation of energy balance, inflammatory biomarkers, cardiometabolic risk factors, nonalcoholic fatty liver disease, and metabolic syndrome. The effects were mediated by improvements in neuroendocrine regulation of energy balance, downregulation of the pro-inflammatory states, and a reduction in comorbidities. Multidisciplinary therapy also improved mood disorders and quality of life.

Reduced insulin clearance in paediatric metabolic (dysfunction)-associated fatty liver disease and its dual role in beta-cell offload and diabetes risk

AIM

Diminished hepatic insulin clearance (HIC) is observed in obese adults and is presumed to be mediated by fatty liver. However, few reports have examined HIC in Chinese children with metabolic (dysfunction)-associated fatty liver disease (MAFLD). This study aimed to investigate the correlation between HIC, insulin sensitivity and β-cell function in obese Chinese children with MAFLD.

METHODS

In total, 204 obese children (74 MAFLD) aged 4-17 years were enrolled into this study. HIC, insulin sensitivity and β-cell function were calculated using the oral glucose tolerance test (1.75 g/kg body weight). Correlation analyses between the HIC and clinical variables were performed using Pearson's product-moment correlation coefficients. HIC and glucose homeostasis were assessed in a high-fat diet mouse model, and liver samples were collected for molecular analysis.

RESULTS

Obese children with MAFLD exhibited significantly lower HIC (AUCC-peptide/insulin ratio, p = 0.0019), higher insulin resistance (homeostatic model assessment of insulin resistance, p = 0.002), and increased compensatory β-cell function (homeostatic model assessment-β, p = 0.046) than obese children without liver involvement. Notably, HIC was negatively correlated with insulin sensitivity (r = -0.5035, p < 0.0001) and β-cell function (r = -0.4576, p < 0.0001). However, pancreatic β-cell dysfunction (p = 0.046) was accompanied by future reduced HIC (p = 0.034) in children with MAFLD in prediabetes. In a high-fat diet mouse model, MAFLD mice showed a 50% reduction in insulin-degrading enzyme expression, consistent with the observed decrease in HIC.

CONCLUSIONS

A lower HIC may offload pancreatic β-cells at an early stage. However, obese children with MAFLD are at risk of developing diabetes, and preventive efforts should be prioritized.

Chronic unpredictable mild stress increases serum aldosterone without affecting corticosterone levels and induces hepatic steatosis and renal injury in young adult male rats

Stress is often associated with anxiety and depressive symptoms in adolescents. Stress is associated with components of metabolic syndrome and inflammation. The present study hypothesizes that aldosterone, more than corticosterone, promotes chronic stress-hepatic steatosis and fibrosis, as well as renal inflammation and fibrosis in young adult rats. Thirty-two young adult male Wistar rats of 51 days old were divided into four groups (n = 8 per group): Control (C), chronic unpredictable mild stress (CUMS), control plus vehicle (C plus veh), CUMS plus eplerenone, a selective aldosterone blocker (CUMS plus EP). On postnatal day 51, eplerenone was administered orally through a gastric tube two hours before the start of the stress test. The CUMS paradigm was administered once daily at different times, with no repetition of the stressor sequence for four weeks. Renal inflammation and fibrosis were measured, as well as liver glycogen, triacylglycerol, and fibrosis levels. The serum concentrations of corticosterone, aldosterone, sodium, and creatinine were measured in urine and serum. The CUMS group showed a high level of serum aldosterone without affecting the level of corticosterone, increased urinary sodium, tubular atrophy, glomerular sclerosis, the presence of inflammation, and fibrosis, without affecting creatinine, increased glycogen content, triacylglycerol, and moderate fibrosis in the liver, and treatment with eplerenone prevented the inflammation, fibrosis, glycogen, and triacylglycerol. Our results show that chronic stress-induced aldosterone promotes hepatic steatosis and renal injury more than corticosterone. The prevention by eplerenone supports our hypothesis.

Joint modeling of association networks and longitudinal biomarkers: An application to childhood obesity

The prevalence of chronic non-communicable diseases such as obesity has noticeably increased in the last decade. The study of these diseases in early life is of paramount importance in determining their course in adult life and in supporting clinical interventions. Recently, attention has been drawn to approaches that study the alteration of metabolic pathways in obese children. In this work, we propose a novel joint modeling approach for the analysis of growth biomarkers and metabolite associations, to unveil metabolic pathways related to childhood obesity. Within a Bayesian framework, we flexibly model the temporal evolution of growth trajectories and metabolic associations through the specification of a joint nonparametric random effect distribution, with the main goal of clustering subjects, thus identifying risk sub-groups. Growth profiles as well as patterns of metabolic associations determine the clustering structure. Inclusion of risk factors is straightforward through the specification of a regression term. We demonstrate the proposed approach on data from the Growing Up in Singapore Towards healthy Outcomes cohort study, based in Singapore. Posterior inference is obtained via a tailored MCMC algorithm, involving a nonparametric prior with mixed support. Our analysis has identified potential key pathways in obese children that allow for the exploration of possible molecular mechanisms associated with childhood obesity.

Criteria in the Diagnosis of Metabolic Syndrome in Children: A Scoping Review

Currently, there is no consensus on the criteria for identifying metabolic syndrome in children, as observed in the diversity of research developed. For this reason, a scoping review was developed in this work, in order to compare the criteria for the diagnosis of metabolic syndrome (MetS) applied in children, described in observational, descriptive cross-sectional studies. The databases PubMed, Scopus, Web of Science and the search engine Google Scholar were used. The search terms "metabolic syndrome", "cardiometabolic syndrome", "child", "children" and "childhood" were considered, as well as the names of organizations or authors proposing identification criteria for MetS to establish search relationships using the Boolean connectors "AND" and "OR". Likewise, two reviewers carried out the evaluation and selection of articles, of which 26 articles were included in which children aged 6 to 12 participated. It was found that the most commonly used criteria for identifying MetS since 2015 are those of Cook et al, IDF, NCEP ATPIII, and De Ferranti et al, in that order. Specific criteria, such as those proposed by Cook et al, are being chosen to enhance the accuracy of identifying MetS in children. The most common risk factors in children with MetS are abdominal circumference and BMI, followed by triglycerides, HDL, blood pressure, and blood glucose. The prevalence of MetS in children varies according to the criteria used, being higher with De Ferranti et al.

Diagnostic Performance of Biomarker-Based Scores as Predictors of Metabolic Dysfunction-Associated Fatty Liver Disease Risk in Healthy Children

INTRODUCTION

Metabolic dysfunction-associated fatty liver disease (MAFLD)-a new definition for non-alcoholic fatty liver disease-reflects the impact of metabolic abnormalities on liver function. We assessed the diagnostic accuracy of biomarker-based scores for prediction of MAFLD in apparently healthy children.

METHODS

This study included 144 children aged 9-11. MAFLD was recognized in 14 girls and 29 boys. Anthropometric indices, glycemia, insulin resistance, lipid profile, enzymes (ALT, AST, GGT, ALP), CRP, N-terminal propeptide of type I procollagen (P1NP) and collagen type I C-telopeptide (CTX-1) levels were measured. Fatty liver and hepatic steatosis index (FLI, HSI) and potential indicators of liver fibrogenesis: P1NP/ALP, P1NP/ALPxALT, P1NP/ALPxCRP were calculated.

RESULTS

P1NP/ALPxALT and P1NP/ALPxCRP were significantly higher in subjects with MAFLD. FLI was a good, significant predictor of MAFLD occurrence, regardless of sex. In boys, P1NP/ALPxCRP was a comparable predictor as CRP (OR 1.14 vs. 1.17; p < 0.001). P1NP/ALPxCRP had better discrimination capability in boys (AUC = 0.79; p < 0.001). However, the use of this algorithm did not improve discriminatory power in comparison to CRP (AUC = 0.81; p < 0.001), but gave a better sensitivity for MAFLD prediction (86% vs. 59%).

CONCLUSIONS

We suggest that P1NP/ALPXCRP is a reliable tool for MAFLD prediction in routine pediatric practice.

An adult-based genetic risk score for liver fat associates with liver and plasma lipid traits in children and adolescents

BACKGROUND & AIMS

Genome-wide association studies have identified steatogenic variants that also showed pleiotropic effects on cardiometabolic traits in adults. We investigated the effect of eight previously reported genome-wide significant steatogenic variants, individually and combined in a weighted genetic risk score (GRS), on liver and cardiometabolic traits, and the predictive ability of the GRS for hepatic steatosis in children and adolescents.

APPROACH & RESULTS

Children and adolescents with overweight (including obesity) from an obesity clinic group (n = 1768) and a population-based group (n = 1890) were included. Cardiometabolic risk outcomes and genotypes were obtained. Liver fat was quantified using 1 H-MRS in a subset of 727 participants. Variants in PNPLA3, TM6SF2, GPAM and TRIB1 were associated with higher liver fat (p < .05) and with distinct patterns of plasma lipids. The GRS was associated with higher liver fat content, plasma concentrations of alanine transaminase (ALT), aspartate aminotransferase (AST) and favourable plasma lipid levels. The GRS was associated with higher prevalence of hepatic steatosis (defined as liver fat ≥5.0%) (odds ratio per 1-SD unit: 2.17, p = 9.7E-10). A prediction model for hepatic steatosis including GRS alone yielded an area under the curve (AUC) of 0.78 (95% CI 0.76-0.81). Combining the GRS with clinical measures (waist-to-height ratio [WHtR] SDS, ALT, and HOMA-IR) increased the AUC up to 0.86 (95% CI 0.84-0.88).

CONCLUSIONS

The genetic predisposition for liver fat accumulation conferred risk of hepatic steatosis in children and adolescents. The liver fat GRS has potential clinical utility for risk stratification.

Effect of Gestational Fish Oil Supplementation on Liver Metabolism and Mitochondria of Male and Female Rat Offspring Programmed by Maternal High-Fat Diet

SCOPE

Perinatal maternal moderately high-fat diet (mHFD) is associated with obesity and fatty liver disease in offspring, and maternal fish oil (FO: n-3 PUFA source) supplementation may attenuate these disorders. This study evaluates the effects of FO given to pregnant rats fed a mHFD on the offspring's liver at weaning.

METHODS AND RESULTS

Female Wistar rats receive an isoenergetic, control (CT: 10.9% from fat) or high-fat (HF: 28.7% from fat) diet before mating, and throughout pregnancy and lactation. FO supplementation (HFFO: 2.9% of FO in the HF diet) is given to one subgroup of HF dams during pregnancy. At weaning, male and female mHFD offspring display higher body mass, adiposity, and hepatic cellular damage, steatosis, and inflammation, accompanied by increased damaged mitochondria. FO does not protect pups from systemic metabolic alterations and partially mitigates hepatic histological damage induced by mHFD only in females. However, FO reduces mRNA expression of lipogenic genes, and mitochondrial damage, and modified mitochondrial morphology suggestive of early adaptations via mitochondrial dynamics.

CONCLUSIONS

Gestational FO supplementation has limited beneficial effects on the damage caused by perinatal mHFD consumption in offspring's liver at weaning. However, FO imprinting effect on lipid metabolism and mitochondria may have beneficial long-term outcomes.