Gotu kola (Centella asiatica ) is a member of the Apiaceae carrot family. It is also called pennywort, marsh penny, water pennywort, and sheep rot. The name sheep rot comes from the erroneous belief in Europe that gotu kola caused foot rot in sheep. Gotu kola is often mistaken for the kola nut plant (Cola nitida ). However, the two are not related and gotu kola, unlike the kola nut, contains no caffeine . Gotu kola is noted in India as a very powerful spiritual herb, and Ayurvedic medicine refers to it as Brahmi because it helps obtain knowledge of the spiritual being.
Gotu kola, a perennial, grows in India, Sri Lanka, Madagascar, South Africa, China, Indonesia, Australia, and North America. It can grow like a weed, but its description depends on its location. For example, in shallow water, the leaves float; but in dry areas, the plant develops many roots and thin, tiny leaves. The fan-shaped leaves may be smooth or lobed. Red flowers turn into fruit with a diameter of about 0.2 in (5 mm).
Gotu kola's main active components are triterpenoids, although the gotu kola found in India, Sri Lanka, and Madagascar doesn't have the same properties. Gotu kola's triterpenes can have a concentration from 1.1-8%, with most concentrations in the middle range.
Gotu kola from Madagascar is used for most standardized extracts, and its four main triterpene properties are:
- asiatic acid (29-30%)
- madecassic acid (29-30%)
- asiaticoside (40%)
- madecassoside (1-2%)
Gotu kola also contains the following.
- volatile oil of a terpene acetate (36% of all the volatile oil)
- glycerides of some fatty acids
- plant sterols (campesterol, stigmasterol, sitosterol)
- polyacetylene compounds
- flavonoids (kampferol, quercetin)
- myo-inositol (glycoside from the flavonoids)
- amino acids
Traditional use of gotu kola in India and Indonesia included wound treatment. In the 1800s, it became part of Indian medicine practice and was used to treat many skin conditions including leprosy, varicose ulcers, and eczema , as well as fever, diarrhea , and absence of menses.
Chinese medicine uses various parts of the plant. The leaves are used for leukorrhea and fevers that are toxic, while other types of fevers and boils are treated with gotu kola shoots. Gotu kola used for longevity has become very popular. Chinese herbalist, Li Ching Yun, is supposed to have lived 256 years from drinking a herbal mixture containing gotu kola. An ancient Sinhalese saying, "Two leaves a day will keep old age away," also illustrates gotu kola's popularity as an agent for longevity.
The plant enhances brain and peripheral circulation, and is said to enhance memory. In the 1880s, the French began using gotu kola as part of regular pharmaceutical medicines.
Many current uses are similar to traditional uses of the plant. In a 1992 study at Kasturba Medical College, researchers fed rats gotu kola extract. After 14 days, the gotu kola-treated rats showed 3-60 times better retention of learned behavior than did rats who didn't receive the extract.
Gotu kola may also play a role in fighting Alzheimer's disease , which affects over four million people in the United States. People with this dementiacausing disease have unusual amounts of the protein betaamyloid (also called plaque) in the brain. A 1999 study conducted by pathology professor Alan Snow at Seattle's University of Washington showed gotu kola's potential for treatment. Snow first mixed a compound from cat's claw and tested it in rats and in test tubes. Results showed that cat's claw intervenes with plaque formation. When other extracts were added to the test tubes, including gotu kola and rosemary , the results were more pronounced.
Besides its use as a general memory aid, gotu kola has become popular in the Western world for its calming effects as well as for improving concentration. This duality occurs because gotu kola affects both the central nervous system and the brain. It relaxes the nervous system while stimulating the brain to focus better. In a 1999 study at the West Palm Beach Veterans Affairs Medical Center, researchers tested several dietary supplements, including gotu kola, for use in depression, anxiety , and sleep disorders . Researchers found little difference in the results of the natural supplements and low- and high-dose antidepressants. However, the studies indicated patients switch to natural supplements because they think they are safer. The research served as a guideline for healthcare professionals to aid their patients' choice of treatment.
Studies have also shown that gotu kola has positive effects on varicose veins , poor blood circulation in the legs and the rest of the circulatory system, leg cramps, and leg swelling. The circulatory improvement occurs because gotu kola decreases vein hardening, improves the connective tissue around veins, and helps the blood to flow through veins. These circulatory and leg benefits were evident in 80% of patients tested in studies conducted in the late 1980s.
Gotu kola also has positive effects on various skin problems. Animal research has shown that tripenoid asiaticoside may help wounds heal quicker. Other studies showed that gotu kola helped in healing surgical wounds of the ear, nose, and throat, and promoted healing of episiotomies, gangrene , skin grafts, and some skin ulcers. Asiaticoside can also toughen skin, hair, and nails. Research has shown that asiaticoside may provide treatment for leprosy. Leprosy-causing bacteria are coated in a wax-like substance that the immune system can't penetrate. However, gota kola disintegrates this substance, allowing the immune system to attack the bateria.
Clinical trials also show that gotu kola's tripenoids, when purified, can lessen the ravages of scleroderma. Gotu kola can reduce hardening of the skin, decrease joint pain , and increase finger movement.
Gotu kola extracts can heal second- and third-degree burns from boiling water or gas explosions if the burn is treated immediately. Either topical application or intramuscular injections can stop the effects of skin infections from burns and can stop or reduce skin shrinkage, inflation, and scarring.
Gotu kola extract might be effective in fighting tumors. However, researchers are cautious because animal and human studies need to be completed.
Today, gotu kola is often eaten in a salad. It can also be made into a tea by using 0.5–1 tsp (2.5–5 ml) of gotu kola in 1 cup (250 ml) of boiling water. The plant is steeped for 10–15 minutes and the tea is then drunk. This amount can be drunk up to three times a day. Because of its bitter taste, the tea can be enhanced with honey or lemon to taste.
For a poultice on wounds or skin problems, gotu kola leaves can be crushed and applied, or a tincture may be used. A poultice can also be made from gotu kola tea.
For scleroderma, suggestions include 70 mg twice a day. The usual dosage is 0.5–1 g three times daily, a standardized extract dosage is 60–120 mg a day, and a liquid extract approximately 0.5–1 teaspoon can be taken daily.
Children under two years old, pregnant women, and people with epilepsy should avoid gotu kola. Fair-skinned people and others who have had an allergic reaction to sunlight or other ultraviolet light sources should avoid these sources if they take gotu kola.
A rash is the most common side effect when gotu kola is taken internally or applied topically. If injected, some pain and bruising may occur at the injection sight. The asiaticoside component could be a mild skin carcinogen. It is not wise to apply gotu kola topically over a long period of time. The plant may also cause mild headaches or nausea . As with any supplement, consultation with a healthcare professional should occur before beginning treatment.
Gotu kola should not be mixed with oral diabetes medication or drugs such as Lipitor, Lopid, Mevacor, and Zocor, all of which lower cholesterol . Gotu kola can raise cholesterol. It is also best not to mix gotu kola with alcohol or sedatives.
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