[1] It is the active chemical constituent responsible for the medicinal properties of the plant, which have been used for centuries by the Khoisan people of southern Africa to treat diverse health disorders, including fever, diabetes, hypertension, and various blood related diseases.
[2] Harpagoside is characterized as an iridoid glycoside, which is a product of the mevalonate pathway present in the metabolism of eukaryotes, archaea and some bacteria.
The iridane skeleton found in iridoids is monoterpenoid in origin and contains a cyclopentane ring fused to a six-membered oxygen heterocycle.
Biochemical studies have elucidated the mechanism of action of pure harpagoside, showing that it moderately inhibited cyclooxygenases 1 and 2 of the arachidonic acid pathway ( COX – 1/2) and overall nitric oxide production in human blood.
COX 1 and 2 are key enzymes of the arachidonic acid pathway and it has been shown that inhibitors of these cyclooxygenases have implications for treating rheumatoid arthritis.