Fig. 5

IL-29 enhanced obesity-induced insulin resistance and increased macrophage number in HFD mice. C57BL/6 mice were randomly assigned to the NCD (10% kcal derived from fat) or the high-fat diet (HFD; 60% kcal derived from fat) group for 16 weeks. HFD mice were divided into three groups (n = 5 mice per group): HFD mice without treatment, HFD mice treated with 0.5 mg/kg IL-29, and HFD mice treated with 1 mg/kg IL-29 twice a week. a Body weight was measured weekly. b The fat pad weight and weight gain were measured after 16 weeks. Data are expressed as mean ± SEM and are representative of three independent experiments. c RT-qPCR analysis of IL-28R1 and IL-10R2 mRNA expression in the visceral white adipose tissue (WAT) of HFD mice and NCD mice after 16 weeks. *P < 0.05 compared with NCD mice. d A glucose tolerance test (GTT) and e an insulin tolerance test (ITT) was performed at weeks 15 and 16, respectively, after IL-29 treatment. *P < 0.05 compared with PBS-treated HFD mice. f The adipose tissues from PBS-treated and IL-29-treated HFD mice were analyzed using immunoblotting with specific antibodies against phosphor-AKT and GLUT4. β-actin was an internal control. g Total peritoneal cells from PBS-treated and IL-29-treated HFD mice were stained with anti-CD11c, anti-F4/80, and anti-CD206 and analyzed by FACS. A dot plot defining the F4/80⁺ cells in the peritoneum of HFD mice. F4/80⁺ cells were quantified by flow cytometry. h, i The absolute cell numbers and total percentage of F4/80⁺ macrophages in peritoneum of PBS-treated and IL-29-treated HFD mice. *P < 0.05 compared with PBS-treated HFD mice. j, k Expression of CD11c and CD206 was measured as mean fluorescence intensities (MFIs) by flow cytometry. l–o F4/80, CD11c, CD206, and MCP-1 mRNA expression in adipose tissues isolated from PBS-treated and IL-29-treated HFD mice were analyzed using RT-qPCR with specific primers. *P < 0.05 compared with PBS-treated HFD mice. p Ratio of CD11c⁺ cells relative to resident CD206⁺ cells was calculated in MFI units. Data are expressed as mean ± SEM and are representative of three independent experiments. *P < 0.05 compared with PBS-treated HFD mice. q The numbers of CD11b⁺Ly6G⁺ neutrophils in adipose tissue of PBS-treated and IL-29-treated HFD mice. Data are expressed as mean ± SEM. *P < 0.05 compared with the PBS-treated HFD mice