Fig. 6

IL-33 was modulated in adipogenesis via the Wnt/β-catenin/PPAR-γ signaling pathway. 3T3-L1 cells were transfected with IL-33 siRNA before adipogenic differentiation, and 72 h later, the cells were incubated for adipogenic differentiation and treated with OA for hyperadipogenic differentiation. (a) Protein levels of LRP6, GSK3β, p-GSK3β, β-catenin, cyclin D1, PPAR-γ, H3, and β-actin were measured by Western blot analysis. (b) Expression of β-catenin was detected by indirect immunofluorescence staining with FITC-conjugated corresponding secondary antibodies (scale bar = 100 μm). DNA was stained with DAPI. (c–g) Cells were induced with Wnt agonist 1 (10µM) and collected on day 10. (c) Protein levels of PPAR-γ were measured by Western blot analysis. (d) Oil Red O staining was conducted after adipogenesis (scale bar = 100 μm). (e) Semi-quantitative detection of cells in different groups by Oil Red O staining (detection at 492 nm). (f) Determination of cellular TG levels. (g) Schematic models illustrating the role of IL-33 in inhibiting adipogenic differentiation in adipocytes. The data are represented as the mean ± SEM (n = 3).^*P < 0.05, ^**P < 0.01, ^***P < 0.001, and ^****P < 0.0001