The literature is abundant with experimental and clinical trial data about the horse chestnut and its chemically purified biologically active components. The seeds contain 30 to 60% of starch, escin, protein, fatty oils, sugar, catechine tannins. The leaves contain flavonoids (quercetine), carotinoids (lutein).
Based on the experimental studies of the rabbit v.portae and human v.saphena (segments obtained by surgical removal of varicosities), the scientists concluded that the tonic effect of escin results from stimulation of prostaglandin production and release in vascular walls. A strong antiphlogistic effect of escin was also observed, which is five times higher when a natural sum of chestnut flavonoids is added. It should be pointed out in this respect that many researchers believe that the therapeutic effect of escin does not coincide with the individual effect of any of the active components known today to be present in the horse chestnut. It is most likely that the effect results from the sum of these components and maybe a number of still unknown agents.
Horse chestnut medicines exhibit a venotropic effect due to the presence of saponins – escin and esculin. Active substances have a vasoprotective and venotonic effect, an antioxidative effect combined with the ability to inhibit enzymes destroying venous structures (collagenase, hyaluronidase, elastase, etc.), and normalize the metabolism of proteoglycans in vascular walls. Escin expressively influences the venous valves and prevents a reflux and a hypoxic tissue damage thanks to the cytoprotective effect, it reduces the excretion of inflammation mediators. The ultimate effect of its action is the prevention of excessive vascular permeability and a higher venous tonus. The efficacy of the horse chestnut seed extract against the chronic venous insufficiency was studied in various controlled trials. The drugs of this range were shown to decrease the shank edema, to reduce cramps, severity of pains, fatigue, tension, itching. That's why they may be recommended for treatment of the early chronic venous insufficiency (evidence level B). The effect of escin on the lymph flow is important: the drug contributes to edema abatement by enhancing the lymph flow through the thoracic duct.
