Figure 2

Metabolic reprogramming in rheumatoid arthritis T cells. In contrast to healthy CD4 T cells, rheumatoid arthritis T cells fail to upregulate glycolytic activity due to the insufficient induction of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), a key regulatory enzyme in the glycolytic pathway. Deficient activity of PFKFB3 shunts glucose towards the pentose phosphate pathway and increases intracellular NADPH levels, hence unbalancing the cell’s redox status. 6PGDH, 6-phosphogluconate dehydrogenase; F-1,6-P, fructose-1,6-bisphosphatase; F-2,6-P, fructose-2,6-bisphosphatase; F-6-P, fructose-6-phosphate; FASN, fatty acid synthase; G-6-P, glucose-6-phosphate; G6PD, glucose-6-phosphate dehydrogenase; GSH, glutathione; GSSG, glutathione disulfide; NADPH, nicotinamide adenine dinucleotide phosphate; PFK, 6-phosphofructo-2-kinase; R-5-P, ribose 5-phosphate; TCA, tricarboxylic acid.