Researchers block malaria parasite

Approximately 220 million people are infected each year by the Plasmodium parasite, which causes malaria. Between 655,000 and 12 million do not survive. The research team led by Maria Mota at the Institute of Molecular Medicine at the University of Lisbon (IMM) has discovered a way to destroy the parasite even before the first symptoms appear. The results of the study were recently published in the journal PNAS.

When it enters the body through a mosquito bite, the Plasmodium parasite travels to the liver and settles in a liver cell (hepatocyte), where it is supplied with nutrients. From there, it multiplies, taking on a new form. This is the first stage of infection, which is still asymptomatic. It then enters the bloodstream and begins to attack red blood cells. The first symptoms then appear, usually violently. In the blood, the parasite repeats the cycle, this time infecting red blood cells and reinforcing the symptoms of the disease.

In attempting to understand the parasite's nutrient capture mechanism in hepatocytes during the initial phase, which is crucial for the development of the infection, IMM researchers discovered a new class of highly potent antimalarial compounds—torins, known for their ability to block cancer progression. When testing the effect of these compounds in infected mice, they found that torins destroy the parasites in the blood phase, but also prevent the parasite from multiplying in the liver by blocking the formation of the vacuole where the parasite multiplies within the hepatocyte. Without the formation of the vacuole, the parasite can be eliminated by the host cell. The next step will be to develop torins that can be used in human clinical trials.