French researchers have gained a new insight into the mechanism for fighting malaria which could be used to develop low cost drugs. 

Malaria kills millions of people in Asia and Africa, but the drugs currently available are often too expensive for these countries. Philippe Manivet, at the Public Assistance Hospital of Paris, and colleagues have been investigating an alternative low cost way to generate toxic radical species for destroying the malaria parasite. 

Artemisinin is a natural product, found in the shrub sweet wormwood, used by Chinese herbalists to treat malaria. It has significant anti-malarial drug activity, and its reactivity with iron in the blood has been the focus of many scientific studies. 'Everybody was convinced that artemisinin generates radical chemical species which kill the parasite,' explains Manivet, 'however only putative chemical routes were proposed without any clear arguments,' he adds. 'We were not convinced by those routes since they did not fit with our clinical and biochemical observations.'  

Manivet's team used quantum chemistry calculations to investigate the mechanism, and found that artemisinin is not directly toxic and active by itself on the malaria parasite. It, in fact, interacts with ferrous iron to act as a chemical intermediate that leads to the production of radicals that kill the malaria parasite. 

In the future, Manivet hopes to further decipher the mechanism and thinks this may prove useful in the development of low cost anti-malaria drugs based on artemisinin.

Sarah Dixon