Synonyms: Kombé seed
Scientific Name: Strophanthus kombe Oliv.
Family: Apocynaceae (dogbane family)
Cardiac glycosides, mainly strophanthin, fatty oil.
If you want to see this plant with the exotic name in its natural habitat you will have to travel a long way. The small, climbing shrub from the liana family grows in the hot, dry forests of East Africa. It is often to be found in mountainous regions and has a milky sap. The ovoid leaves have hairs on both sides when young. As they age their surfaces become more grooved, almost wrinkled. From October to December white flowers grow in pairs at the tips of its branches. Their elongated petals end in twisting thread-like points which lend the plant an exotic elegance. Later the flowers produce straight, pod-like seed heads which always grow in twos facing each other. When the seeds are ripe the pods burst lengthways and release seeds covered in fluffy hairs which are caught by the wind and disseminated.
The glycoside strophanthin has a similar effect on the heart to digitalis. It acts in three distinct ways. Administered intravenously, strophanthin combats congestive heart failure. Given orally as a chewable capsule it is used for the prevention or acute treatment of heart attack and angina pectoris. A tincture made from the seeds also effectively supports cardiac performance, especially in functional disorders of the heart muscle and coronary arteries. These are heart complaints that have no organic cause but are triggered by excessive physical or emotional pressures which lead to stress.
One of the advantages strophanthin has over digitalis is that does not accumulate in the organism. Just six hours after administration of the drug, strophanthin is nearly undetectable in the myocardium. This makes it easier to adjust the dose as necessary.
The name strophanthus is made up of the Greek words strophos = twisted cord plus anthos = flower, and fittingly describes the somewhat bizarre form of the flower. The epithet kombé refers to the African name for the plant.
The Scottish missionary and well-known Africa explorer David Livingstone (1813-1873) brought strophanthus back with him to Europe in the middle of the 19th century. The action of the plant on the heart was recognised by the Scottish botanist John Kirk (1832-1922) who travelled with Livingstone and himself suffered from angina pectoris. Once as he was cleaning his teeth his heart pains disappeared and he discovered that his toothbrush had accidentally been contaminated with a small amount of the arrow poison from strophanthus seeds used for hunting in Africa.
The molecular basis for this cardiac activity was researched by the British physician and pharmacologist Thomas Richard Fraser (1841-1920), who isolated the cardioactive glycoside from the seed. The breakthrough in strophanthin therapy came in 1906 with research by the German physician Albert Fraenkel (1864-1938). He verified the positive action of strophanthin on the heart after intravenous administration and established its use as a standard medical therapy. Until about 1950 strophanthin was widely used as cardioactive drug, its popularity being reflected in names such as ‘milk for the aging heart’. During this period heart patients carried strophanthin capsules as emergency medicine.
Medicines such as digitalis and beta-blockers widely replaced strophanthus preparations in the 1950s and the following decades. But in 1991 a discovery by an American group of researchers renewed interest in strophanthin: the human organism produces this glycoside in the adrenal gland and in the brain, and secretes it during physical activity or stress to regulate blood pressure. In English-speaking countries this human strophanthin is better known as ouabain.