Figure 5. The pharmacological inhibition of Tpl2 or its silencing in adipocytes prevents the induction of COX-2 and the secretion of PGE2 induced by a coculture between adipocytes and macrophages.

A, COX-2 mRNA expression in 3T3-L1 adipocytes and RAW macrophages cultured separately (A+M) or cocultured in contact system (Coc) with DMSO (vehicle) or with a Tpl2-I (5μM) for 24 hours (n = 4 experiments). B, Immunoblot analysis and quantification (n = 4 experiments) of COX-2 protein expression with Hsp90 as loading control in the same experimental conditions as in A. C, COX-2 mRNA expression (n = 3 experiments) in 3T3-L1 adipocytes (left) or RAW macrophages (right) cocultured in the transwell system or cultured separately without (vehicle, DMSO) or with a Tpl2-I (5μM). D, COX-2 mRNA expression in 3T3-L1 adipocytes treated for 48 hours with control siRNA (Ad siC) or Tpl2 siRNA (Ad siT) and cocultured in the transwell system with RAW macrophages (n = 3 experiments). E, 3T3-L1 adipocytes treated with a control siRNA (Ad siC) or a Tpl2 siRNA (Ad siT) were cultured with RAW macrophages either separately (A+M) or in contact coculture (Coc) for 24 hours. The relative amount of COX-2 mRNA expression is presented (n = 4 experiments). F, Immunoblot and quantification (n = 5 experiments) of COX-2 protein expression with Hsp90 as loading control in the same experimental conditions as in E. G, PGE2 amount in the medium in the same experimental conditions as in E and F. Data from 4–5 independent experiments are presented. Data in bar graphs represent mean ± SEM with *, P < .05; **, P < .01; and ***, P < .001.