Aldose reductase is a human enzyme that converts aldehydes into alcohols by the addition of hydrogen (H) to to a double bonded oxygen site (C=0 becomes C-OH).
Aldose reductase reduces the aldehyde portion of glucose creating the sugar alcohol sorbitol.
Effects on Norepinephrine Metabolism
The normal pathway in humans for norepinephrine (NE) is deamination by monoamine oxidase (MAO), forming an aldehyde which is then either metabolized to 3,4-dihydroxy-mandelic acid (DHMA) by aldehyde dehydrogenase or is converted to 3,4-dihydroxyphenylglycol (DHPG) by or aldose reductase.
The same metabolic pathways exists in rats. In vivo tests performed on rats given aldose reductase inhibitors caused a sharp increase in the formation of DHMA and a decrease in the formation of DHPG. Because human metabolism of NE follows the same pathway it can be concluded that inhibition of aldose reductase in humans should produce an increase in DHMA and a decrease in DHPG.
|Potent Inhibitors||Strength||Dosage||Verified in Man|
|Cuminaldehyde||IC50 0.00085 mg/mL1||?||?|
|Cinnamaldehyde||IC50 0.003 mg/mL2||?||?|
|Quercetin||IC50 2 mM||?||?|
|Rutin||IC50 5 mM||?||?|
|Moderate Inhibitors||Strength||Dosage||Verified in Man|
|Black pepper water extract||0.22 mg/ml||?||?|
|Orange fruit water extract||0.25 mg/ml||?||?|