Research team came across the substance “Parabulin”: It stopped the growth of parasites in a laboratory test. Further tests should pave the way for a new drug.
An international team led by the Paul Scherrer Institute (PSI) has discovered a target for drugs to disarm pathogenic parasites. They then identified an active ingredient that inhibits the growth of the single-cell parasite Toxoplasma gondii, the causative agent of toxoplasmosis. The researchers hope that the discovered substance “Parabulin” can be used widely in the future.
Pregnant women in particular fear this disease because it can damage the unborn child so much that it leads to miscarriage. The source of infection is, for example, poorly cooked meat or cat feces. Like the malaria pathogen, Plasmodium, Toxoplasma gondii is one of the so-called Apicomplexa.
The team around PSI scientists Natacha Gaillard and Ashwani Sharma have now deciphered the molecular structure of the tubulin of a ciliate, which is virtually identical to that in Apicomplexa, Gaillard said in a message from the research institute on Monday. Tubulins are thread-like proteins that play a key role in cell division. If they are blocked, cell division gets mixed up – the parasites can no longer multiply.
This is exactly what the researchers succeeded in doing after they came across a substance in a database that they named “Parabulin”.
In a laboratory test, parabulin docked specifically to the tubulin of the parasite Toxoplasma gondii and stopped its growth. The substance did not affect human cells, as the team reports in the specialist magazine “EMBO Molecular Medicine”.
There is currently a lack of safe and effective drugs against diseases caused by Apicomplexa. In addition, more and more parasites developed resistance to conventional drugs, the researchers write. Therefore, novel active ingredients are urgently needed.
The tubulin protein has been known for a long time in tumor research, but it has hardly received any attention in parasitology, said Sharma. Stopping the replication of parasites with the help of tubulin-specific inhibitors could therefore be a useful way of discovering drugs against Apicomplexa.
According to the PSI, Parabulin should not only act against Toxoplasma gondii, but against all representatives of the Apicomplexa parasites. The PSI is now filing a patent and plans to test the substance further in the laboratory “in order to later develop it into a drug with the help of the pharmaceutical industry,” according to the research institute.