Immune challenge induces metabolic activation and transition of monocytes to macrophages with increased GLUT1 expression, glucose uptake, and glycolysis

The transition of monocytes to macrophages is characterized by increased 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 increased production of inflammatory cytokines. Alternatively activated macrophages (M2) trigger a metabolic profile with oxidative phosphorylation (OxPhos) and an anti-inflammatory response. Legend: TNF, tumor necrosis factor; IL-6, interleukin 6; IL-1RA, interleukin-1 receptor antagonist. (Source: Vulturar R, Chis A, Pintilie S, et al. One molecule for mental nourishment and more: glucose transporter type 1-biology and deficiency syndrome. Biomedicines 2022;10[6]:1249. Creative Commons Attribution License [CC BY], https://creativecommons.org/licenses/by/4.0. Figure edited by Dr. Douglas J Lanska.)