Fig. 3

Knockdown of IL-33 promoted the adipogenesis of 3T3-L1 preadipocytes. Before adipogenesis, 3T3-L1 cells were transfected with IL-33 siRNA, and 72 h later, the cells were incubated for adipogenic differentiation and treated with OA for hyperadipogenic differentiation. Meanwhile, the cells were induced with 30 ng/mL recombinant IL-33. The cells after 10-day induction were tested. (a) The efficacy of IL-33 knockdown in 3T3-L1 cells was confirmed using RT-qPCR. (b) Oil Red O staining; scale bar = 100 μm. (c) Semi-quantitative detection of cells in different groups using Oil Red O staining (detection at 492 nm). (d) Cellular TG levels were quantified. (e–j) RT-qPCR was conducted to evaluate the expression of the adipogenic factors PPAR-γ, C/EBPα, FABP4, LPL, Adipoq and CD36 after 10-day induction. The data are represented as the mean ± SEM (n = 3). ^*P < 0.05, ^**P < 0.01, ^***P < 0.001 and ^****P < 0.0001. PPAR-γ, Peroxisome proliferator-activated receptor gamma; C/EBPα, CCAAT/enhancer-binding protein α; FABP4, Fatty acid binding protein 4; LPL, lipoprotein lipase; Adipoq, adiponectin; CD36, platelet glycoprotein 4