Findings of a recent study have shown that Plasmodium parasite, the infectious agent responsible for malaria, is able to sense and actively adapt to the host’s nutritional status.
Using mouse models of malaria infection, scientists led by Maria M. Mota from Instituto de Medicina Molecular in Lisbon, found that mice that ate 30% fewer calories had a significantly lower parasite load.
Plasmodium parasites reproduce inside red blood cells every 48 hours and the new study has shown that the parasite’s rate of replication depends on the calories ingested by the host. This may ultimately determine the outcome of a malaria infection – survival or death.
Findings of this study have two possible explanations – either the parasite was actively adapting when changed to a host with lower calorie intake or the parasite has a hard time replicating due to the fact that some essential nutrients were missing in the host’s body.
The research team controlled the food intake of mice before infection with different Plasmodium parasites and studied their response. They found that parasites that were missing an enzyme called KIN had an impaired response to decreased nutrient availability, and replicated at the same speed, regardless of the food available to the mice.
These results imply that KIN acts as a nutrient sensor and major regulator of parasites’ ability to respond to nutritional changes, and that the malaria parasites adapt actively.
According to Dr Oliver Billker, a collaborator on the research, this study is the first of its kind to show how parasites react to a host’s body in relation to nutrition and although further studies is still necessary, findings of the study may have implications for other infectious diseases besides malaria.
A better understanding of this system may also help researchers invent methods that would make the parasite easier to control by slowing its replication.