Hemozoin formation (HZ) (HZ)

Hemozoin formation is a vital biomineralization process used by Plasmodium parasites to detoxify free heme released during the digestion of host hemoglobin [1]. Within the parasite acidic digestive vacuole, free ferriprotoporphyrin IX (heme) is highly toxic, as it can induce oxidative stress and damage biological membranes [2]. To mitigate this, the parasite crystallizes the toxic heme into an insoluble, chemically inert polymer known as hemozoin, or malaria pigment [3]. This detoxification pathway is the primary target for several classes of antimalarial drugs, including 4-aminoquinolines like chloroquine and amino-alcohols like quinine [4]. These drugs act by binding to the heme monomers or the growing crystal faces, thereby preventing further crystallization and causing the accumulation of toxic free heme [5]. The resulting heme-induced damage leads to the rapid death of the parasite during its intraerythrocytic stage [2]. Because humans do not produce hemozoin, this pathway represents a highly selective and effective target for antimalarial therapy [1].

Other names

β-hematin crystallizationMalaria pigment formationHeme detoxification pathwayFerriprotoporphyrin IX sequestration

Inhibition of β-hematin crystallization by binding to heme monomers or crystal growth sites, leading to the accumulation of toxic free ferriprotoporphyrin IX (heme) which causes oxidative damage and parasite death [2, 5].