Superoxide Dismutase Inhibitors against Malaria, Leishmaniasis, and Chagas Disease: Systematic Review.

INTRODUCTION: Diseases caused by protozoa are one of the leading causes of death worldwide, especially in tropical regions such as Brazil. Chagas disease, leishmaniasis, and malaria are responsible for around 234 million cases and more than 400,000 deaths worldwide. Despite this scenario, drugs for these diseases have several limitations, which justifies the search for new treatments. Iron superoxide dismutase is a promising target for the drug design to treat patients with these diseases. It is a validated target and protects against oxidative stress. AIM: Thus, this systematic review aimed to synthesize evidence on the importance of superoxide dismutase in the drug design to treat patients with this protozoosis. METHODS: A search was performed for in vitro and in vivo studies, without publication and language restrictions, in MEDLINE (PubMed), LILACS (BVS), Science Direct, and EMBASE (Elsevier). Studies that pointed to the relationship between the reduction or increase in superoxide dismutase activity and the diseases were included. 23 studies were selected for the qualitative synthesis. RESULTS: The results showed that the inhibition or reduction of the enzyme activity decreases the degree of infection and reinfection and improves the results in treating these diseases. In contrast, the increase in activity caused a high degree of survival and resistance of the parasites. CONCLUSION: However, the overall quality of evidence is low and more studies with methodological rigor are provided.

Small molecules containing chalcogen elements (S, Se, Te) as new warhead to fight neglected tropical diseases.

Neglected tropical diseases (NTDs) encompass a group of infectious diseases with a protozoan etiology, high incidence, and prevalence in developing countries. As a result, economic factors constitute one of the main obstacles to their management. Endemic countries have high levels of poverty, deprivation and marginalization which affect patients and limit their access to proper medical care. As a matter of fact, statistics remain uncollected in some affected areas due to non-reporting cases. World Health Organization and other organizations proposed a plan for the eradication and control of the vector, although many of these plans were halted by the COVID-19 pandemic. Despite of the available drugs to treat these pathologies, it exists a lack of effectiveness against several parasite strains. Treatment protocols for diseases such as American trypanosomiasis (Chagas disease), leishmaniasis, and human African trypanosomiasis (HAT) have not achieved the desired results. Unfortunately, these drugs present limitations such as side effects, toxicity, teratogenicity, renal, and hepatic impairment, as well as high costs that have hindered the control and eradication of these diseases. This review focuses on the analysis of a collection of scientific shreds of evidence with the aim of identifying novel chalcogen-derived molecules with biological activity against Chagas disease, leishmaniasis and HAT. Compounds illustrated in each figure share the distinction of containing at least one chalcogen element. Sulfur (S), selenium (Se), and tellurium (Te) have been grouped and analyzed in accordance with their design strategy, chemical synthesis process and biological activity. After an exhaustive revision of the related literature on S, Se, and Te compounds, 183 compounds presenting excellent biological performance were gathered against the different causative agents of CD, leishmaniasis and HAT.