HFPO‑TA induces developmental hepatotoxicity in hESC‑derived hepatocyte‑like cells by disrupting lipid homeostasis and mitochondrial function

Hexafluoropropylene oxide trimer acid (HFPO-TA), an alternative to perfluorooctanoic acid (PFOA), can cross the placental barrier, raising concerns regarding fetal hepatic development; however, the mechanisms underlying its developmental hepatotoxicity remain poorly elucidated. Here, human embryonic stem cell-derived hepatocyte-like cells (HLCs) were exposed to HFPO-TA at 3, 15, or 75μM for 28 days during hepatocytic differentiation. HFPO-TA accumulated intracellularly in a dose- and time-dependent manner and impaired hepatic function, evidenced by reduced albumin secretion and CYP activity and increased alanine transaminase (ALT) and aspartate aminotransferase (AST) levels. Integrated proteomic and metabolomic profiling revealed extensive disruption of lipid metabolism, including increased triglycerides, total cholesterol, and low-density lipoprotein levels, and decreased high-density lipoprotein levels. HFPO-TA activated PPAR signaling and altered genes and proteins associated with lipid synthesis and oxidation, with significant perturbations even at the environmentally relevant concentration of 3 μM. Oil Red O staining and altered PLIN1 and PLIN2 expression confirmed lipid droplet accumulation. HFPO-TA also disrupted mitochondrial function, altered respiratory chain activity, reduced ATP production and mitochondrial membrane potential, and up-regulated fission-fusion-related genes. Collectively, these findings indicate that HFPO-TA impairs hepatocyte differentiation through PPAR-mediated lipid remodeling and mitochondrial dysfunction, highlighting safety concerns for this PFOA alternative. Furthermore, HLCs are a valuable in vitro model for assessing the developmental toxicity of PFOA alternatives.