Fig. 5: HFD-induced CD63⁺A33⁺ exosomal lipids contribute to insulin resistance in an AhR-dependent manner.

a Representative gene expression heat map for the Affymetrix array of liver tissue from mice orally administered exosomes for 14 days. Induction of AhR expression highlighted in the red box. Elevated AhR expression was confirmed by qPCR (bar graph, right, n = 3). Filled triangle—L-Exo and filled rectangle—H-Exo. b Total AhR protein expression was confirmed by western blots in liver tissue. c Phosphorylated AhR (pAhR) protein expression in hepatocytes (FL83B cells) cultured with L-Exo, H-Exo, L-Exo^lipids, or H-Exo^lipids. Densitometry analysis summarized below. Filled circle—PBS, filled triangle—L-Exo, and filled rectangle—H-Exo. d FL83B cells were cultured with different concentrations (as indicated) of PC (34:2) for 16 h, and the resulting effects on AhR expression were determined by western blots. Ratio to β-actin shown in the middle as numbers. e Glucose uptake assay for FL83B cells cultured with varying concentrations of PC (34:2). f, g SPR sensogram showing the interaction of AhR recombinant protein with nanoparticles derived from total lipids of H-Exo (f) and PC (34:2) (g). h PC direct binding to AhR protein. i SPR was performed with AhR protein-coated onto an NTA chip and H-Exo^{lipid PC−} and PC (34:2)^lipid run over as the mobile phase. j AhR expression in the cytoplasm vs. nucleus of mouse hepatocytes cultured with L-Exo or H-Exo. Densitometry analysis of cytoplasmic (left) vs. nuclear (right) AhR protein expression following treatment with L-Exo or H-Exo summarized below. k GTT and ITT performed on AhR null (AhR^−/−) HFD-fed mice treated with CD63⁺A33⁺ exosomes (L-Exo or H-Exo) for 14 days. l, m Glucose uptake assay performed on AhR-knockout (AhRKO, l) and wild-type (m) FL83B cells. n GTT and ITT of AhR^−/− mice with re-expression of AhR in hepatocytes by adenovirus (5 × 10⁹ pfu) injected via tail vein. Mice were orally gavaged with H-Exo for 14 days while being fed the HFD. Student’s t test, one-tailed. Data represent the mean ± SD. Student t test (two-tailed) or one-way ANOVA with a Tukey post hoc test. * < 0.05 and ** < 0.01. Source data are provided as a Source Data file. Each data point was measured in triplicate.