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