TY - JOUR
T1 - Stability of peroxide antimalarials in the presence of human hemoglobin
AU - Creek, Darren John
AU - Ryan, Eileen
AU - Charman, William Neil
AU - Chiu, Francis Chi Keung
AU - Prankerd, Richard
AU - Vennerstrom, Jonathan
AU - Charman, Susan Ann
PY - 2009
Y1 - 2009
N2 - Peroxide antimalarials, including artemisinin, are important for the treatment of multidrug-resistant malaria. These peroxides are known to react with iron or heme to produce reactive intermediates that are thought to be responsible for their antimalarial activities. This study investigated the potential interaction of selected peroxide antimalarials with oxyhemoglobin, the most abundant form of iron in the human body. The observed stability of artemisinin derivatives and 1,2,4-trioxolanes in the presence of oxyhemoglobin was in contrast to previous reports in the literature. Spectroscopic analysis of hemoglobin found it to be unstable under the conditions used for previous studies, and it appears likely that the artemisinin reactivity reported in these studies may be attributed to free heme released by protein denaturation. The stability of peroxide antimalarials with intact oxyheoglobin, and reactivity with free heme, may explain the selective toxicity of these antimalarials toward infected, but not healthy, erythrocytes.
AB - Peroxide antimalarials, including artemisinin, are important for the treatment of multidrug-resistant malaria. These peroxides are known to react with iron or heme to produce reactive intermediates that are thought to be responsible for their antimalarial activities. This study investigated the potential interaction of selected peroxide antimalarials with oxyhemoglobin, the most abundant form of iron in the human body. The observed stability of artemisinin derivatives and 1,2,4-trioxolanes in the presence of oxyhemoglobin was in contrast to previous reports in the literature. Spectroscopic analysis of hemoglobin found it to be unstable under the conditions used for previous studies, and it appears likely that the artemisinin reactivity reported in these studies may be attributed to free heme released by protein denaturation. The stability of peroxide antimalarials with intact oxyheoglobin, and reactivity with free heme, may explain the selective toxicity of these antimalarials toward infected, but not healthy, erythrocytes.
U2 - 10.1128/AAC.00363-09
DO - 10.1128/AAC.00363-09
M3 - Article
SN - 0066-4804
VL - 53
SP - 3496
EP - 3500
JO - Antimicrobial Agents and Chemotherapy
JF - Antimicrobial Agents and Chemotherapy
IS - 8
ER -