Abstract
BACKGROUND: The rising prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD), particularly among pediatric populations, requires identification of modifiable risk factors to control disease progression. Per- and polyfluoroalkyl substances (PFAS) have emerged as potential contributors to liver damage; however, their role in MASLD remains underexplored. This study aimed to develop a translational framework integrating human and in vitro data to elucidate the effect of PFAS on MASLD development. METHODS: We measured PFAS plasma levels in the Teen-LABS cohort (n = 136), comprising adolescents with obesity (mean age = 16.8 years) undergoing bariatric surgery. Plasma samples were also analyzed using proteomic and metabolomic assays. MASLD was diagnosed by liver biopsy examination. Human liver spheroids were exposed to perfluoroheptanoic acid (PFHpA) in vitro and analyzed by single-cell transcriptomics. The latent unknown clustering with integrated data (LUCID) model was employed to assess associations between PFHpA exposure, multiomic signatures, and MASLD risk. RESULTS: Here we show that, among all PFAS measured, doubling of PFHpA levels is associated with an 80% higher MASLD risk (OR, 1.8; 95% CI: 1.3-2.5). Integrated human and in vitro analyses suggest dysregulation of pathways involved in inflammation and lipid metabolism. A distinct proteome profile is associated with significantly higher odds of MASLD (OR = 7.1). CONCLUSIONS: This study offers evidence implicating PFHpA, a short-chain unregulated PFAS congener, in MASLD development in adolescents, and highlights the critical role of protein dysregulation in disease pathogenesis. The molecular mechanisms identified here can inform the development of targeted prevention and treatment strategies.