Centella includes about 40 species, most of which grow only in South Africa. They are creeping plants with clusters of a few small, long-stalked leaves arising from a thin horizontal stem. Their inflorescences are small and few-flowered, unlike the many-flowered compound umbels of more familiar members of their family. Centella asiatica is distributed almost worldwide in warm, moist habitats. Populations in the southeastern United States (occasionally called C. erecta (L. f.) Fernald) may be found in open sandy areas. Gotu kola features in Ayurvedic, Chinese, and African folk medicine. It is widely used as a tonic herb, to benefit a variety of conditions (ranging from anxiety and venous insufficiency to cancer), and to speed wound healing; it was used for leprosy before the availability of modern treatments. According to one tradition, a leaf should be eaten every day to encourage good health. Gotu kola is also sometimes used simply as an edible plant. Topical preparations are used for wounds and to prevent stretch marks in pregnancy.

Traditional uses of gotu kola are gaining some scientific support. A number of human clinical trials have demonstrated that it protects against microangiopathy (small blood vessel damage) caused by airline travel and benefits diabetic microangiopathy, venous hypertensive microangiopathy, and leg edema; one study shows an anti-anxiety effect and one shows a reduction of stretch marks when a cream is used. However, all human trials to date have been small. Animal studies have shown that use of oral or topical gotu kola extracts or active compounds improves wound healing. In vitro studies have elucidated mechanisms that contribute to both of these activities; active ingredients include asiaticoside and related compounds. Nerve regeneration is also improved in rats. Animal studies have also shown other intriguing effects, including healing ulcers, retarding the development of tumors, limiting cardiac damage from heart attacks, preventing cognitive deficits, enhancing learning ability in newborn animals, and protecting against radiation injury, radiation dermatitis, and radiation-induced taste aversion. Of course, results from animal models may not be applicable to humans. For example, the many rodent studies showing ulcer healing have induced ulcers by using chemicals or stress, whereas most ulcers in humans are caused at least in part by infection with Helicobacter and might not respond in the same way. However, there is certainly adequate evidence of potential benefit to justify greatly increasing the research effort and funding devoted to this herb.

Selected References

Cesarone, M. R., L. Incandela, M. T. De Sanctis, G. Belcaro, G. Geroulakos, M. Griffin, A. Lennox, A. D. Di Renzo, M. Cacchio, and M. Bucci. 2001. Flight microangiopathy in medium- to long-distance flights: prevention of edema and microcirculation alterations with total triterpenic fraction of Centella asiatica. Angiology 52 Suppl 2:S33-37.

De Sanctis, M. T., G. Belcaro, L. Incandela, M. R. Cesarone, M. Griffin, E. Ippolito, and M. Cacchio. 2001. Treatment of edema and increased capillary filtration in venous hypertension with total triterpenic fraction of Centella asiatica: a clinical, prospective, placebo-controlled, randomized, dose-ranging trial. Angiology 52 Suppl. 2:S55-59.

Hamal, I. A., and A. K. Koul. 1989. Taxonomic position of Centella asiatica (L.) Urban. Proc. Indian Acad. Sci., Pl. Sci. 99:363-368.

Huq, A.M., and M. Mahfuzur Rahman. 1990. Hydrocotylaceae. Salar Khan MD, Matiur Rahman M, eds. Flora of Bangladesh, no. 44. Bangladesh National Herbarium, Bangladesh Agricultural Research Council: Dhaka.

Maquart, F. X., F. Chastang, A. Simeon, P. Birembaut, P. Gillery, and Y. Wegrowski. 1999. Triterpenes from Centella asiatica stimulate extracellular matrix accumulation in rat experimental wounds. Eur. J. Dermatol. 9:289-296.

Radford, A.E., H. E. Ahles, and C. R. Bell. 1968. Manual of the Vascular Flora of the Carolinas. Chapel Hill, NC: University of North Carolina Press.

Rouillard Guellec, F., J. R. Robin, A. Rakoto Ratsimamanga, S. Ratsimamanga, and P. Rasaoanaivo. 1997 [publ. 1998]. Etude comparative de Centella asiatica d?origine malgache et d?origine indienne. Acta Bot Gallica. 144:489-493.

Shobi, V., and H. C. Goel. 2001. Protection against radiation-induced conditioned taste aversion by Centella asiatica. Physiol. Behav. 73:19-23.

Shukla, A., A. M. Rasik, G. K. Jain, R. Shankar, D. K. Kulshrestha, and B. N. Dhawan. 1999. In vitro and in vivo wound healing activity of asiaticoside isolated from Centella asiatica. J. Ethnopharmacol. 65:1-11.

Soumyanath, A., Y. P. Zhong, S. A. Gold, X. Yu, D. R. Koop, D. Bourdette, and B. G. Gold. 2005. Centella asiatica accelerates nerve regeneration upon oral administration and contains multiple active fractions increasing neurite elongation in-vitro. J. Pharm. Pharmacol. 57:1221-1229.