FIG. 3.

Macrophage polarization and their effects on insulin regulation. Th2 cytokines such as IL-4 and IL-13 differentiate quiescent (M0) macrophages to M2 phenotype. M2 macrophages maintain the insulin-sensitive state by the release of IL-10 and STAT3. In contrast, Th1 cytokines in the presence of LPS (or other TLR ligands) differentiate macrophages to M1 phenotype. M1 macrophages promote insulin resistance by the release of TNF-α, IL-6, and NO. STAT3, signal transducer and activator of transcription 3. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars