FIGURE 4.

Lipolysis-increased CCL2/MCP-1 expression is dependent on JNK/NFκB/COX-2 signaling pathway. Differentiated 3T3-L1 cells were pretreated with or without an inhibitor of JNK (SP 600125, 10 μm) (A), p38 kinase (SB 203580, 10 μm) (B), NFκB (BAY11-7082, 10 μm) (C), and COX-2 (celecoxib, 5 μm) (D) for 1 h. Subsequently, cells were stimulated with or without ISO (10 μm) for an additional 3 h. Levels of CCL2/MCP-1 (left panels) and IL-6 (right panels) were quantitated by qPCR analysis. Data represent mean ± S.D. of a representative experiment (n = 3), which was repeated at least two times with similar results. **, p < 0.01; *, p < 0.05; NS, not statistically significant; t test. E, 3T3-L1-CAR cells were transduced with a multiplicity of 200 of adenoviral particles carrying rat COX-2 (Ad-COX-2) for indicated times. Expression levels of CCL2, IL-6 (left panel), or rat COX-2 (right panel) were measured by qPCR analysis. Note that ectopic expression of COX-2 significantly increased CCL2 expression. Data are mean ± S.D. of triplicate determinations (**, p < 0.01; t test).