FIGURE 2.

Routes of glucose metabolism in cells. Upon entering a cell via a glucose transporter (GLUT) glucose is phosphorylated by hexokinase entrapping glucose-phosphate. This is then metabolized into glycogen (left), along the pentose phosphate pathway (right) or via glycolysis (center). Glycolysis results in the formation of pyruvate which can be interconverted into lactate through the action of lactate dehydrogenase enzymes. Pyruvate can also enter mitochondria, where it is converted into AcetylCoA through the action of pyruvate dehydrogenase which in turn fuels the tricarboxylic acid cycle (TCAC). The TCAC cycle generates NADH and FADH₂ which are required to supply electrons to the electron transport chain (ETC). The ETC generates a proton gradient across the inner mitochondrial membrane, which is used to power the production of ATP by complex V, an ATP synthase. HK, hexokinase; PDHK4, pyruvate dehydrogenase kinase 4; LDH, lactate dehydrogenase; MCT, monocarboxylate transporter; PDH, pyruvate dehydrogenase; TCAC, tricarboxylic acid cycle; PFKFB3, 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3; PPP, pentose phosphate pathway; ETC, electron transport chain; AcetylCoA, Acetyl coenzyme A; NADH, nicotinamide adenine dinucleotide; FADH₂, flavin adenine dinucleotide; ATP, Adenosine triphosphate; ADP, Adenosine diphosphate. Created with: BioRender.com.