Dried-leaf Artemisia annua : A practical malaria therapeutic for developing countries?
Loading...
Date
2014
Authors
Hassanali, Ahmed
Engeu, Patrick Ogwang
Lutgen, Pierre
Towler, Melissa
Weathers, Pamela J.
Journal Title
Journal ISSN
Volume Title
Publisher
Baishideng Publishing Group Inc
Abstract
Artemisinin from the plant Artemisia 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. annua was 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 of A. annua
may enhance bioavailability of artemisinin. Rodent
pharmacokinetics showed longer T½ and Tmax and greater
Cmax and AUC in Plasmodium chabaudi -infected mice
treated with A. annua dried 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 for A. annua dried
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 affordable A. annua
dried leaf tablets into the arsenal of drugs to combat malaria
and other artemisinin-susceptible diseases.
Description
Article
Keywords
extracted, Artemisinin combination therapy Core tip: Artemisinin, Combination therapy, Artemisinin;, Artemisia annua, Infectious disease, Malaria
Citation
World J Pharmacol 2014 December 9; 3(4): 39-55