Background: Metabolic dysfunction–associated steatotic liver disease (MASLD), formerly known as NAFLD, is the most common liver disease in children. Liver biopsy remains the gold standard for diagnosis, although more efficient screening methods are needed. We previously developed a novel NAFLD screening panel in youth using machine learning applied to high-resolution metabolomics and clinical phenotype data. Our objective was to validate this panel in a separate cohort, which consisted of a combined cross-sectional sample of 161 children with stored frozen samples (75% male, 12.8±2.6 years of age, body mass index 31.0±7.0 kg/m², 81% with MASLD, 58% Hispanic race/ethnicity). Methods: Clinical data were collected from all children, and high-resolution metabolomics was performed using their fasting serum samples. MASLD was assessed by MRI-proton density fat fraction or liver biopsy and cardiometabolic factors. Our previously developed panel included waist circumference, triglycerides, whole-body insulin sensitivity index, 3 amino acids, 2 phospholipids, dihydrothymine, and 2 unknowns. To improve feasibility, a simplified version without the unknowns was utilized in the present study. Since the panel was modified, the data were split into training (67%) and test (33%) sets to assess the validity of the panel. Results: Our present highest-performing modified model, with 4 clinical variables and 8 metabolomics features, achieved an AUROC of 0.92, 95% sensitivity, and 80% specificity for detecting MASLD in the test set. Conclusions: Therefore, this panel has promising potential for use as a screening tool for MASLD in youth.

Metabolic-dysfunction-associated steatotic liver disease (MASLD) is the most common liver disease in children in the US and, if untreated, may progress to end-stage liver disease. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have shown improvement in MASLD markers in adults with type 2 diabetes mellitus (T2DM). Currently, there is a lack of medications available for the treatment of pediatric MASLD. We aimed to provide preliminary data on the effects of GLP-1 RAs on markers of MASLD in a retrospective study, in an effort to bridge this gap in the pharmacotherapies available. Nine patients from a T2DM clinic who met the following inclusion criteria were included in this study: patients diagnosed with pre-diabetes or T2DM, prescribed a GLP-1 RA in the prior 12 months, and having alanine aminotransferase (ALT) elevated to twice the upper limit of the normal range, indicating evidence of MASLD. The average change between baseline and the first measurement after starting a GLP-1 RA was calculated for ALT, hemoglobin A1c, and BMI. ALT decreased by an average of 98 points. A1c decreased by an average of 2.2 points. BMI decreased by an average of 2.4 points. There was greater reduction in ALT and A1c compared to BMI, suggesting that improvement in MASLD may be independent of weight loss. This is a preliminary study that shows potential, and prospective studies are needed to evaluate the effects of GLP-1 RAs in the management of pediatric MASLD.

Little is known about lipid changes that occur in the setting of metabolic-dysfunction-associated steatotic liver disease (MASLD) regression. We previously reported improvements in hepatic steatosis, de novo lipogenesis (DNL), and metabolomic profiles associated with oxidative stress, inflammation, and selected lipid metabolism in 40 adolescent boys (11–16 y) with hepatic steatosis ≥5% (98% meeting the definition of MASLD). Participants were randomized to a low-free-sugar diet (LFSD) (n = 20) or usual diet (n = 20) for 8 weeks. Here, we employed untargeted/targeted lipidomics to examine lipid adaptations associated with the LFSD and improvement of hepatic steatosis. Our LC-MS/MS analysis revealed decreased triglycerides (TGs), diacylglycerols (DGs), cholesteryl esters (ChE), lysophosphatidylcholine (LPC), and phosphatidylcholine (PC) species with the diet intervention (p < 0.05). Network analysis demonstrated significantly lower levels of palmitate-enriched TG species post-intervention, mirroring the previously shown reduction in DNL in response to the LFSD. Targeted oxylipins analysis revealed a decrease in the abundance of 8-isoprostane and 14,15-DiHET and an increase in 8,9-DiHET (p < 0.05). Overall, we observed reductions in TGs, DGs, ChE, PC, and LPC species among participants in the LFSD group. These same lipids have been associated with MASLD progression; therefore, our findings may indicate normalization of key biological processes, including lipid metabolism, insulin resistance, and lipotoxicity. Additionally, our targeted oxylipins assay revealed novel changes in eicosanoids, suggesting improvements in oxidative stress. Future studies are needed to elucidate the mechanisms of these findings and prospects of these lipids as biomarkers of MASLD regression.