Fig. 1: Senescent hepatocytes induced hepatic steatosis, and hepatic 9-HODE and 13-HODE were increased in middle-aged mice.

Oil red O staining of livers (a, b) and hepatic TG and CHO levels of mice (c, d) at 12 months (middle-aged, n = 6 mice per group) or 20 months (aged, n = 5 mice per group) of age; control mice were 2.5 months of age; scale bar = 100 μm. e Immunofluorescence staining of P16 and Nile Red staining of liver sections from mice at 2.5 or 12 months of age; scale bar = 5 μm; yellow arrow: P16⁺ hepatocyte; white arrow: P16^- hepatocyte. f HepG2 cells were treated with 500 μM H₂O₂ for 48 h to induce senescence. Oil Red O staining of senescent hepatocytes or control hepatocytes; (g) HepG2 cells were treated with conditioned medium from senescent hepatocytes or control hepatocytes for 24 h, and then Oil Red O staining was performed; n = 5 independent experiments, scale bar = 100 μm. h–k Liquid chromatography–tandem mass spectrometry (LC‒MS/MS) was performed to detect the PUFA metabolite profile of 2.5- and 12-month-old mice: (h) heatmap, (i) PLS-DA analysis, (j) VIP scores, and (k) volcano plot of significantly changed metabolites; n = 6 mice per group. Data represent the mean ± SEM. Two-tailed student’s t test was performed for (c and left panel of d); Two-tailed Mann-Whitney test for (right panel of d). mo month, TG triglyceride, CHO total cholesterol, CM conditioned medium, Sen senescent, AA Arachidonic acid, LA linoleic acid, EPA eicosapentaenoic acid.