Malaria parasite heme detoxification pathway

The malaria parasite, Plasmodium spp., digests host hemoglobin within its food vacuole, releasing free heme, which is highly toxic to the parasite due to its ability to generate reactive oxygen species[1][2][3][5]. To survive, the parasite detoxifies heme primarily by converting it into an inert crystalline pigment called hemozoin[1][2][3][4][5][6]. This process is catalyzed by specific parasite proteins, notably the heme detoxification protein (HDP)[2][3], and potentially aided by other molecules such as histidine-rich protein 2 (PfHRP-2)[4] and lipid mediators. The heme detoxification pathway is a unique, parasite-specific process and a proven target for antimalarial drugs—most famously chloroquine and artemisinin derivatives, which disrupt hemozoin formation, causing toxic heme accumulation and parasite death[2][4][6][7]. Disruption of this pathway can protect the host from severe malaria pathogenesis, such as cerebral malaria[3]. Drug resistance, primarily due to alterations in drug targets or parasite detoxification machinery, is a major safety and therapeutic challenge.

Other names

Heme detoxification pathwayHemozoin formation pathwayPlasmodium heme detoxification

Inhibition of heme crystallization to hemozoin, alkylation or binding of free heme to prevent detoxification, interference with protein or lipid catalysts involved in hemozoin formation