摘要Background:Acute liver injury(ALI)requires rapid hepatic regeneration to avert fatal liver failure.As key mechanisms,systemic metabolic remodeling and inter-organ crosstalk are critical for this regenerative process.Skeletal muscle,as a major metabolic organ system,undergoes significant remodeling during ALI.However,its specific regulatory contributions remain largely uncharacterized.Methods:Partial(2/3)hepatectomy and acetaminophen were used to induce ALI in male mice.RNA-sequencing(RNA-seq),assay for transposase-accessible chromatin by sequencing(ATAC-seq),chromatin immunoprecipitation,luciferase assay,Western blotting,TUNEL assay,immunohistochemistry,and phase separation assays were performed to reveal the transcriptional axis involved.Serum fibroblast growth factor binding protein 1(FGFBP1)protein levels in ALI patients were assessed via enzyme-linked immunosorbent assay.Results:Integrated analysis of RNA-seq and ATAC-seq following ALI identifies glucocorticoid(GC)signaling-mediated regulation of fibroblast growth factor 6(FGF6)in skeletal muscle metabolism.Muscle-specific knockdown of GC receptor(GR)exacerbates ALI and suppresses liver regeneration.Fgf6-knockout mice exhibited improved ALI and enhanced liver regeneration,with intramuscular injection of FGF6-neutralizing antibody rescuing the detrimental effects induced by GR knockdown.Further analysis of the FGF6 downstream target revealed that FGF6 regulates FGFBP1 expression through extracellular signal regulated kinase-activating transcription factor 3 signaling.Moreover,FGF6 regulates the heparin-dependent release kinetics of FGFBP1 by perturbing its liquid-liquid phase separation(LLPS)-driven condensate dynamics at the plasma membrane.Circulating FGFBP1 subsequently interacts with hepatic FGF5 through LLPS mechanisms to regulate liver regeneration.Conclusion:Our results demonstrate a molecular mechanism by which muscle-liver crosstalk can initiate and sustain liver regeneration via the FGF6-FGFBP1/FGF5 axis,providing a potential therapeutic target and treatment strategy for ALI.