4-1BB/4-1BBL Interaction Promotes Obesity-Induced Adipose Inflammation by Triggering Bidirectional Inflammatory Signaling in Adipocytes/Macrophages
Figure 1
4-1BB and 4-1BBL expression is upregulated by obesity-related factors in adipocytes and macrophages. 4-1BB and 4-1BBL mRNA expression in SVF-derived adipocytes (a) during adipogenesis. SVF-derived confluent preadipocytes (day 0) were differentiated into adipocytes (days 2–4), as described in Section 2. 4-1BB and 4-1BBL mRNA levels in SVF-derived adipocytes and peritoneal macrophages treated with obesity-related factor (250 μM Pal, 100 ng/mL LPS) for 24 and 4 h (b). 4-1BB/4-1BBL mRNA (c) and protein expression (d) in 3T3-L1 adipocytes and Raw264.7 macrophages treated with obesity-related factor (250 μM Pal, 100 ng/mL LPS) for 24 h and 4 h. mRNA was measured by qRT-PCR, and protein levels were detected by FACS. 4-1BB and 4-1BBL mRNA levels in 3T3-L1 adipocytes/Raw264.7 macrophages cocultured for 24 h (e), control indicates mixed adipocytes/macrophages, which were cultured separately for 24 h and mixed after harvest, and in the epididymal adipose tissue (f) of mice fed a high-fat diet (HFD) or low-fat diet (LFD) ( mice per group). Levels of mRNA were estimated by qRT-PCR. Pal, palmitic acid; Adipo, adipocytes; P.MØ, peritoneal macrophages; Raw MØ, Raw264.7 macrophages. Data are the mean ± SEM of three independent experiments performed in duplicate. ; ; ; (compared with control).
