(With additional reports from The Guardian)
Biter Kola botanically called ‘Garcinia kola’ is a tropical flowering plant found in western and central Africa and it produces brown, nut-like seeds. It has been used in African culture for centuries for medicinal purposes. Garcinia kola contains dimeric flavonoid, which is believed to have many healing benefits.
Used in folklore remedies for the treatment of ailment such as liver disorders, hepatitis, diarrhea, laryngitis, bronchitis and gonorrhoea, Garcinia kola belongs to the family Guittiferae and it is commonly called Orogbo in Yoruba language and Aki ilu in Igbo while the English name is bitter kola. Although valued because of its edible nut, the plant exhibits very potent pharmacological activities such as antioxidant, antibacterial, antiviral, antifungal and anti-inflammatory properties. The anti-oxidant property of GK is attributed to its very high content of ascorbic acid.
It is usually found in the tropical rain forest region of West Africa. It prevails as a multi-purpose tree crop in the home gardens of southern Nigeria. It grows to a height of about 12 – 14m and produces reddish, yellowish or orange coloured fruit. Each fruit contains 2 to 4 yellow seeds and a sour tasting pulp. The seeds when chewed have a bitter astringent taste. The flowering of the plant occurs between December and January while the fruits mature between June and August.
Bitter kola is used in many tropical countries to fight infectious diseases such as Aids and the Ebola virus. It has shown to posses anti-inflammatory, antimicrobial and antiviral properties.
Bitter kola is often used to treat the symptoms of colds. It is suggested, in particular, for coughs and sneezing.
Bitter kola is sometimes believed to cure impotence.
Garcinia kola has been successfully used to treat patients suffering from knee osteoarthritis, according to a study published in the Journal of Orthopaedic Surgery. It reduced pain and swelling and improved movement.
Garcinia kola is known for its anti-inflammatory and antioxidant properties. It is used to prevent infections and viruses, especially of the immune system.
Garcinia kola is used as a substitute for hops in brewing lager beer. It is especially useful in preventing beer spoilage.
…..And Researchers affirm its efficacy
In a report published recently in The Internet Journal of Pulmonary Medicine. 2009:Volume 11 Number 1, the researchers: A.K. Okojie ,I. Ebomoyi,C.N. Ekhator,O. Emeri,J. Okosun, G. Onyesu, O. Uhuonrenren, and J. Atima from the Department of Physiology, University of Benin and Ambrose Alli University Ekpoma,in a holistic review decided to find out the physiological mechanism(s) underlying the use of GK for the treatment of asthma. Specifically they were interested in finding out the function(s) of its phytochemical contents and how they are beneficial in the treatment of asthma.
At the end, they said:"Garcinia kola appears to be very promising in the treatment and management of asthma, Our review showed that xanthone and flavonoid, which are its major phytochemical contents inhibit calcium influx and histamine release stimulated by IgE dependent ligands respectively."
Garcinia kola is highly valued because of its medicinal use. The seeds are chewed as an aphrodisiac or used to cure cough, dysentery, chest colds in herbal medicine.
The plant has also found usefulness in the treatment of stomach ache and gastritis. In fact, Professor Maurice Iwu, the chairman of INEC in a study carried out at the University of Nigeria Nsukka reported the use of the plant for the treatment of jaundice, high fever, and as purgative.
Gk has been shown to inhibit smooth muscle activity. It relaxes the smooth muscles of the uterus and the intestine. Although, Gk lacks caffeine, its alkaloid and biflavonoids fractions are said to relax the smooth muscles. Gk has a bronchodilatory effect.
The seeds are used in the treatment of bronchitis and throat infections. They are also used to prevent and relieve colic, cure head or chest colds and relieve cough. Also, the plant is used for the treatment of liver disorders and as a chewing stick.
Asthma is a very common chronic disease involving the respiration system. Episodic or chronic wheezing, cough, and feeling of tightness in the chest as a result of bronchoconstriction characterize it. The fundamental cause is still unknown despite intensive research. However, three abnormalities are present: airway obstruction that is at least partially reversible, airway inflammation, and airway hyper responsiveness to a variety of stimuli. A link to allergy has long been recognized, and plasma IgE levels are often elevated.
The fundamental problem in asthma appears to be immunological. In immunologic model, asthma is a disease mediated by reaginic (IgE) antibodies bound to mast cells in the airway mucosa. On reexposure to an antigen, antigen-antibody interaction on the surface of mast cells triggers both the release of mediators stored in the cells granules and the synthesis and release of other mediators. The agents responsible for the early reaction mediating bronchoconstriction including histamine, tryptase and other neural proteases, leukotrienes C4 and D4, and prostaglandin causes muscle contraction and vascular leakage. The mechanisms underlying bronchial reactivity, such as ozone exposure, allergen inhalation, and infection with respiratory viruses also cause airway inflammation. In humans, the increase in bronchial reactivity induced by ozone is associated with an increase in the number of polymorphonuclear leukocytes found in fluid obtained by bronchial lavage or from bronchial mucosa biopsies. The increase in reactivity due to allergen inhalation is associated with an increase in both eosinophils and polymorphonuclear leukocytes in bronchial lavage fluid. Whatever the mechanisms responsible for bronchial hyperreactivity, bronchoconstriction itself seems to result not simply from the direct effect of the released mediators but also from their activation of neural or humoral pathways.
Intake of Gk will therefore reduce the inhibition of antihistamine activity of flavonoids by copper which is as a result of its high content of vitamin C and zinc. Some studies noted that naturally occurring plant flavonoids affect a variety of cell activation phenomena including the secretion of histamine from human basophils. They also showed that flavonoids inhibit the degranulation of mast cells. Degranulation of mast cells would release not only histamine, but all the mediators of the allergy response.
The review reported that flavonoids exhibited anti-spasmodic and anti-inflammatory properties induced by acetylcholine, histamine, noradrenaline and barium chloride in four different smooth muscles. In addition, flavonoids are said to inhibit antigen-induced release of histamine from mast cells, basophils and also inhibit contractions induced by histamine, acetylcholine and PGEÂÂÂ2. It was noted that this effect was concentration dependent.
Flavonoids are said to inhibit phospholipids metabolism and 5- lipoxygenase (5-LO). Leukotrienes are derived from arachidonic acid through 5-LO and the nucleophilic attack to produce peptidoleukotrienes. These 5-LO products mediate constriction of airway smooth muscles, leukocyte chemotaxis and vascular permeability. Therefore inhibiting 5-LO can attenuate leukotriene production.
The presence of phenol in GK further indicated that it could act as anti-inflammatory, antioxidant and immune enhancers. Phenols have been responsible in having the ability to block specific enzymes that cause inflammation. They also modify the prostaglandin pathways and thereby protect platelet from clumping.
From this review, the following could be the underlying physiological mechanisms by which Garcinia kola may be beneficial in the treatment of asthma:
"Garcinia kola appears to be very promising in the treatment and management of asthma. There is therefore the need to further examine its various phytochemical contents on respiratory smooth muscle, with a view to possibly formulating its extracts or active constituents as medicines."