Induction of Heme Oxygenase-1 with Hemin Reduces Obesity-Induced Adipose Tissue Inflammation via Adipose Macrophage Phenotype Switching

Figure 2

HO-1 induction reduces inflammatory responses in adipocytes and macrophage cocultures. ((a)–(c)) Raw264.7 macrophages were seeded onto 3T3-L1 adipocytes with/without being pretreated with the indicated concentrations of hemin or CORM-2 for 24 h. ZnPP and RuCl₃ were used as HO-1 competitive inhibitor and CORM-2 negative control, respectively. As a control, adipocytes and macrophages were cultured separately, with cell numbers per well equal to those in the contact system. TNF-α (a) and IL-6 (b) protein levels were detected by ELISA. Adiponectin mRNA was detected by qRT-PCR (c). The experiment was set up in triplicate. ((d) and (e)) Adipocytes and macrophages were treated with macrophage-conditioned medium (M-CM) and adipocyte-conditioned medium (Adi-CM), respectively, with/without hemin and CORM-2 pretreatment at the indicated concentrations for 1 h. JNK phosphorylation (p-JNK)/JNK and IκBα were measured by western blotting. Experiment was performed in duplicate. Results are means ± SEM. , , and .

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