Wednesday, October 27th, 2021 -- On October 18th, researchers finally identified a chemical compound that may be suitable to serve as an active agent against several different parasites, including malaria. Tumour research has shown that blocking the protein tubulin in cancer cells prevents cells from multiplying, which can be helpful in chemotherapy. Similarly, researchers at the Paul Scherrer Institute (PSI) in Villigen, Switzerland have applied this phenomenon to unicellular parasites. These parasites also need tubulin for multiplication, and this makes an excellent attacking point for drugs.
From amoebae to humans, all eukaryotes produce the protein tubulin in the form of long filaments. The protein differs slightly depending on the organism, and scientists first explored the precise structure of tubulin to find active agents against the protein specific to parasites. PSI researchers isolated tubulin from cells of Tetrahymena thermophila, which is almost identical to parasites, preventing them from working with malaria pathogens in the laboratory.
Using a variety of light sources, the researchers deciphered the structure of the protein and searched for a chemical compound capable of inhibiting the protein. A data bank yielded five candidates as potential active agents with one chemical compound proving effective. This compound was named “Parabulin,” and it prevents tubulin from forming long, stable proteins, successfully blocking cell division.
PSI’s cooperation partners at the University of California in Irvine, USA tested the compound on Toxoplasma gondii, one of the parasites in human cells; the parasite was practically unable to reproduce any more cells without affecting human cells. This is an excellent sign since the substance only affects the tubulin of the parasite, an essential requirement to be utilized as a drug. It is assumed that parabulin works not only against Toxoplasma gondii, but also against the malaria pathogen. PSI has now filed a patent and continues to test parabulin to develop it into a drug later in the future.
Sources:
(2021) New active agent against parasites. In: Paul Scherrer Institute (PSI). https://www.psi.ch/en/media/our-research/new-active-agent-against-parasites. Accessed 19 Oct 2021
Helpful Definitions
Parasite: any organism that benefits from and is nourished by a host that it lives on (or inside of); a parasite functions at the expense of its host
Tubulin: protein that assembles into long chains forming microtubules, which regulate cell growth
Pathogen: disease-causing organism that is spread easily throughout the body