fructose metabolism

Last reviewed 01/2018

Plasma fructose may enter cells for glycolysis or gluconeogenesis by one of two pathways:

  • in hepatocytes:
    • fructokinase converts fructose to fructose-1-phosphate
    • fructose-1-phosphate aldolase converts fructose-1-phosphate to dihydroacetone phosphate and glyceraldehyde
    • triose kinase converts glyceraldehyde to glyceraldehyde-3-phosphate
    • triose phosphate isomerase converts dihydroacetone phosphate to glyceraldehyde-3-phosphate
    • glyceraldehyde-3-phosphate then enters further glycolytic or gluconeogenic reactions according to the energy status of the hepatocyte

  • in other cells, particularly adipocytes:
    • hexokinase converts fructose into fructose-6-phosphate; fructose competes with glucose for phosphorylation
    • fructose-6-phosphate enters glycolysis