Demonstrating resistance-mitigating effect of artemisia annua phytochemical blend with in-vitro cultures of plasmodium falciparum and in-vivo with plasmodium berghei anka in Mice

Lucy N. Kangethe, Hassanali  Ahmed, Sabah Omar, Dr Johnson kinyua


Lucy N. Kangethe [1], Hassanali  Ahmed [2], Sabah Omar[3], Dr Johnson kinyua [1],

  1.  Department of Biochemistry Jommo Kenyatta University of Agriculture and Technology P.O BOX 62000 00100 Nairobi, Kenya
  2. Department of Chemistry Kenyatta University P.O BOX 43844- 00100 Nairobi, Kenya
  3. Kenya Medical Research Institute P.O BOX 54840-00200 Nairobi,  Kenya.

Resistance of Plasmodium falciparum to drugs such as chloroquine and sulfadoxine-pyrimethamine is a major problem in malaria control. Artemisinin derivatives, particularly in combination with other drugs, are thus increasingly used to treat malaria, reducing the probability that parasites resistant to the components will emerge. Although stable resistance to artemisinin has yet to be reported from laboratory or field studies, its emergence would be disastrous because of the lack of alternative treatments.

The project was designed to demonstrate resistance-mitigating effects of phytochemical blend of Artemisia annua relative to pure artemisinin against the malaria parasite Plasmodium falciparum and on rodent malaria parasite Plasmodium berghei Anka. For the in vitro experiments selection was undertaken on two cultures of P. falciparum D6 (CQ-sensitive strain from Sierra Leone) and W2 (CQ-resistant strain from Indochina), by exposing them to A. annua phytochemical blend and the pure artemisinin over 50 cycles at doses initially required to give 50% mortality (IC50)of the parasites. Dose-response effectsof the blend and the pure compound were determined after 10, 20, 30, and 40, cycles and compared to see if significant difference developed in their efficacy in causing mortality of the parasites.

The in vivo experiments mice have been done by inoculating the Swiss mice with the P. berghei ANKA parasite and thereafter treated them with the test drugs. After 4 days the mice were passaged and parasitaemia determined to calculate the ED50 and the ED9O. The ED50 andED90 got for artemisinin with P. berghei ANKA was 1.43 and 7.18 mg/kg.day respectively while the ED50 andED90 got for the blend  with P. berghei ANKA was 34.5 and 118 mg/kg.day respectively. The chloroquine resistant murine plasmodium (p yoelii) was also tested using artemisinin and ED50 andED90 got was 11.63 and 29.8 mg/kg.day respectively. The efficacy of dihydroartemisinin was also determined in order to compare with artemisinin and the ED50 andED90 got for artemisinin with P. berghei ANKA was 1.73 and 8.31 mg/kg.day respectively.

One Response to Demonstrating resistance-mitigating effect of artemisia annua phytochemical blend with in-vitro cultures of plasmodium falciparum and in-vivo with plasmodium berghei anka in Mice

  1. Felicitas Roelofsen says:

    congratulations. I think it is very important to have these data to support the use of artemisia annua in malaria treatment. I just have one question, is the Artemisia plant you have been using a hybrid? How much is the concentration of artemisinin.
    To make it easyer please reply to my mail ID F.Roelofsen@web.de

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