Figure 1: Classically activated M1-like macrophages in adipose tissue. Pro-inflammatory macrophages contribute to insulin resistance by feed forward mechanisms of inflammatory cytokines such as TNF and IL-1β produced by the NLRP3 inflammasome. TLRs are activated by ligands like LPS and SFA and initiate intracellular signalling pathways leading to further induction of pro-inflammatory genes and cytokines. Futhermore, signalling through the mineralcorticoid receptor (MR) contributes to M1-polarization by production of pro-inflammatory cytokine production and inhibition of M2-polarization.