title: Dried-leafArtemisia annua:A practical malaria therapeutic for developing countries?
abstract: Artemisinin from the plantArtemisia annua (A. annua)L, and used as artemisinin combination therapy (ACT), is the current best therapeutic for treating malaria, a disease that hits children and adults especially in developing countries. Traditionally,A. annuawas used by the Chinese as a tea to treat "fever". More recently, investigators have shown that tea infusions and oral consumption of the dried leaves of the plant have prophylactic and therapeutic efficacy. The presence of a complex matrix of chemicals within the leaves seems to enhance both the bioavailability and efficacy of artemisinin. Although about 1000-fold less potent than artemisinin in their antiplasmodial activity, these plant chemicals are mainly small molecules that include other artemisinic compounds, terpenes (mainly mono and sesqui), flavonoids, and polyphenolic acids. In addition, polysaccharide constituents ofA. annuamay enhance bioavailability of artemisinin. Rodent pharmacokinetics showed longer T1/2and Tmaxand greater Cmaxand AUC inPlasmodium chabaudi-infected mice treated withA. annuadried leaves than in healthy mice. Pharmacokinetics of deoxyartemisinin, a liver metabolite of artemisinin, was more inhibited in infected than in healthy mice. In healthy mice, artemisinin serum levels were > 40-fold greater in dried leaf fed mice than those fed with pure artemisinin. Human trial data showed that when delivered as dried leaves, 40-fold less artemisinin was required to obtain a therapeutic response compared to pure artemisinin. ACTs are still unaffordable for many malaria patients, and cost estimates forA. annuadried leaf tablet production are orders of magnitude less than for ACT, despite improvements in the production capacity. Considering that for > 2000 years this plant was used in traditional Chinese medicine for treatment of fever with no apparent appearance of artemisinin drug resistance, the evidence argues for inclusion of affordableA. annuadried leaf tablets into the arsenal of drugs to combat malaria and other artemisinin-susceptible diseases.
authors: Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA 01609, United States.
authors: Pamela J
authors: PJ
authors: Weathers
authors: Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA 01609, United States.
authors: Melissa
authors: M
authors: Towler
authors: School of Pure and Applied Sciences, Kenyatta University, Nairobi 20100, Kenya.
authors: Ahmed
authors: A
authors: Hassanali
authors: IFBV-BELHERB, PO Box 98, L-6908 Niederanven, Luxembourg.
authors: Pierre
authors: P
authors: Lutgen
authors: Natural Chemotherapeutics Research Institute, Ministry of Health, PO Box 4864 Kampala, Uganda.
authors: Patrick Ogwang
authors: PO
authors: Engeu
keywords: Artemisia annua; Artemisinin; Artemisinin combination therapy; Combination therapy; Infectious disease; Malaria