In Leishmania the glutathione/glutathione reductase eukaryotic redox system is replaced by the unique trypanothione/trypanothione reductase (TR) system. In vitro, silver is a more effective TR inhibitor than antimony, the first line drug against leishmaniasis in most endemic countries, and its mechanism of inhibition is similar to that of Sb(III). In particular, silver binds with high affinity to the catalytic triad Cys52, Cys57, and His461', thereby inhibiting TR. Here, Ag(0) activity was tested on the promastigote and amastigote stages of Leishmania infantum using a drug-delivery system consisting in Ag(0) nanoparticles encapsulated by ferritin molecules (PfFt-AgNPs). These were able to induce an antiproliferative effect on the parasites at metal concentrations lower than those used with antimony.
Inhibitory Effect of Silver Nanoparticles on Trypanothione Reductase Activity and Leishmania infantum Proliferation
Ilari A;Ceci P;Colotti G
2011
Abstract
In Leishmania the glutathione/glutathione reductase eukaryotic redox system is replaced by the unique trypanothione/trypanothione reductase (TR) system. In vitro, silver is a more effective TR inhibitor than antimony, the first line drug against leishmaniasis in most endemic countries, and its mechanism of inhibition is similar to that of Sb(III). In particular, silver binds with high affinity to the catalytic triad Cys52, Cys57, and His461', thereby inhibiting TR. Here, Ag(0) activity was tested on the promastigote and amastigote stages of Leishmania infantum using a drug-delivery system consisting in Ag(0) nanoparticles encapsulated by ferritin molecules (PfFt-AgNPs). These were able to induce an antiproliferative effect on the parasites at metal concentrations lower than those used with antimony.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


