Oxidative Stress and Survival of Leishmania spp.: A Relationship of Inverse Proportionality for Disease Outcome.

SEARCH RESULTS: Reactive oxygen species (ROS) play a dual role in leishmaniasis by contributing to both host defence and parasite survival mechanisms. In the host, ROS promote parasite clearance through induction of apoptosis, activation of pro-inflammatory signalling pathways (e.g., MAPK, JNK), inflammasome assembly, and M1 macrophage polarisation. Conversely, Leishmania species have evolved multiple strategies to neutralize ROS, including the upregulation of host antioxidant enzymes like HO-1, inhibition of ROS-producing pathways, and expression of parasite-derived antioxidants such as SOD, GPx, and trypanothione reductase. The parasite alsoadapts through gene regulation and metabolic changes to counter oxidative stress. Importantly, ROS have emerged as key targets for antileishmanial therapies, with various drugs and natural compounds shown to induce ROS-mediated parasite death, highlighting their potential in future therapeutic development.

CONCLUSIONS: In summary, the survival of Leishmania hinges on its ability to counteract host-induced oxidative stress. Targeting its antioxidant defences and enhancing host ROS production can disrupt this balance, leading to parasite death. Exploring ROS-related signalling offers a promising path for developing effective therapies against leishmaniasis.