FIG. 5.
Model for the mode of action of Sb(III) on Leishmania. Sb(III) is known to attack the thiol metabolism of Leishmania parasites in two distinct ways (41). First, Sb(III) inhibits TryR in intact cells, resulting in accumulation of the disulfide forms of T[S]2. Second, Sb(III) decreases thiol buffering capacity by inducing rapid efflux of intracellular T[SH]2. These two mechanisms combine to profoundly compromise the thiol redox potential in drug-sensitive parasites and lead to the accumulation of ROS (23).