Function
The aldose reductase reaction, in particular the sorbitol produced, is important for the function of various organs in the body. For example, it is generally used as the first step in a synthesis of fructose from glucose; the second step is the oxidation of sorbitol to fructose catalyzed by sorbitol dehydrogenase. The main pathway from glucose to fructose (glycolysis) involves phosphorylation of glucose by hexokinase to form glucose 6-phosphate, followed by isomerization to fructose 6-phosphate and hydrolysis of the phosphate, but the sorbitol pathway is useful because it does not require the input of energy in the form of ATP:
- Seminal vesicles: Fructose produced from sorbitol is used by the sperm cells.
- Liver: Fructose produced from sorbitol can be used as an energy source for glycolysis and glyconeogenesis.
Aldose reductase is also present in the lens, retina, Schwann cells of peripheral nerves, placenta and red blood cells.
Read more about this topic: Aldose Reductase
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