Sleeping sickness parasite’s pores act as efficient drug uptake mechanism

Scientists have discovered how drugs that have been used for 60 years to kill the parasite that causes sleeping sickness actually work. Research has revealed that the drugs used to attack Trypanosoma brucei enter through pores in the parasite's cells known as aquaporins which function as water channels. It is the first time that drugs have been shown to enter cells through aquaporins and this may have major implications for drug delivery in other diseases. Dr Harry de Koning, a Reader of Biochemical Parasitology at the University of Glasgow who has been studying drug resistance mechanisms in pathogenic protozoan parasites, said: "This research is a breakthrough in understanding how the drugs used to attack the sleeping sickness parasite get inside their target: like spies into an enemy castle they enter through a water channel. "The discovery heralds a new paradigm for drug uptake by cells, as this is the first time that drugs have been shown to enter cells through aquaporins. "Although there have been some reports of these channels being permeable to inorganic ions or small molecules, this is the first detailed report of an aquaporin acting as a genuine transport protein rather than a passive channel for mainly water." The Glasgow researchers, in collaboration with Professor David Horn of the University of Dundee, identified a genetic link between a single parasite gene and its susceptibility to the drugs pentamidine and melarsoprol, which were first introduced in the 1930s and 1940, respectively.