Three ‘neglected’ tropical diseases targeted by scientists
Three neglected tropical diseases have recently been the target of scientists from various institutions and they say they are closer to providing effective treatmentsafter making a chemical which can kill the parasites that cause the illnesses.
The tropical diseases, Chagas disease, leishmaniasis and human African trypanosomiasis (also known as sleeping sickness), affect 20 million people worldwide and lead to more than 50,000 deaths annually.
They are spread by the bite of three very distinct insects – triatomine bugs, sandflies and tsetse flies – and have very different symptoms as well – one can cause cardiac arrest in 30% of people infected, another can cause skin lesions and swelling of the liver and spleen and can destroy the lining of your nose, and the last can infect the brain and cause a disturbance in the sleep cycle which leads victims to comatose and death, respectively.
These diseases also infect people in different regions of the world. Chagas affects populations in South America, African trypanosomiasis is mainly within Africa, and leishmaniasis infects across both continents, as well as Asia.
But the parasites that cause these diseases have some similar biology and genomic sequence, suggesting that all three diseases could be cured with a single class of drug.
The drugs currently used to treat the diseases can have severe side effects, can require intravenous delivery in a hospital and need to be taken for a month or more, making them less than ideal in the poverty-stricken communities where the diseases occur.
Scientists were able to identify an enzyme common to all three parasites and develop a chemical that binds to the “target” and prevents it from functioning.
They screened more than 3 million compounds for their effect against each parasite in both mice and human cells. One, called GNF6702, not only killed all three, it didn’t cause any damage when applied to human cells — suggesting that there would be no side effects.
When the newly identified compound was tested in infected mice, levels of the parasite became undetectable for all three diseases.
The Genomics Institute of the Novartis Research Foundation (GNF) led the research along with their colleagues at the Novartis Institute for Tropical Diseases (NITD), University of York, University of Washington and the University of Glasgow.
Professor Jeremy Mottram, Chair in Pathogen Biology at the Centre for Immunology and Infection at the University of York, said: “It’s a breakthrough in our understanding of the parasites that cause the three diseases, potentially allowing them to be cured.
“This early phase drug discovery project will now move towards toxicity testing prior to human trials.”
Category: Features, Health alert
