Figure 4.

Immune challenge induces metabolic activation with increased GLUT1 expression, glucose uptake and glycolysis. The transition of monocytes to macrophages is characterized by further increases in Glut1 expression and glycolysis. Naive (unactivated) monocytes are metabolically quiescent, with low basal metabolic activity and ATP derived primarily via oxidative phosphorylation (OxPhos). Classically activated macrophages (M1) induce aerobic glycolysis, resulting in lactate production and the increased production of inflammatory cytokines. Alternatively activated macrophages (M2) trigger a metabolic profile with OxPhos and an anti-inflammatory response. TNF: Tumor necrosis factor; IL-6: Interleukin 6; IL-1RA: interleukin-1 receptor antagonist.