Atividade tripanocida de compostos bioativos oriundos de algas e cianobactérias: uma revisão

Abstract

Chagas disease (CD), classified as a neglected tropical disease second to World Health Organization, is caused by the parasite Trypanosoma cruzi, which can assume two evolutive forms in the human host: trypomastigote and amastigote. DC possesses two clinical phases, the acute phase (generally asymptomatic) and the chronic phase (which can affect the cardiovascular, digestive and/or nervous systems). The currently available drugs to treat CD, benznidazole (BZN) and nifurtimox (NFX), are known for their high toxic profile, especially NFX. BZN, the first-line treatment, possesses limited efficacy in the chronic phase of CD and mechanisms of resistance had been associated to it. Thus, new compounds with trypanocidal activity are necessary to act as an alternative treatment against CD. Natural compounds are described as promising alternative for antiparasitic treatment. Algae and cyanobacteria are promising sources of bioactive compounds since they perform various biological activities reported in the literature, including antiparasitic activity. Therefore, this work aimed to make a review exploiting the antiparasitic activity of the biocompounds from algae and cyanobacteria against both trypomastigote and amastigote forms of T. cruzi. For this, it was conducted a search in Science Direct, Medline (PubMed), Web of Science (WoS), Springer Link, Wiley Online Library, Scielo, and MDPI. In total, 15 studies were included and the Rhodophyta and Ochrophyta phyla are the more studied and more promising for anti-T cruzi activity. The macroalgae Dictyota dichotoma and Ulva lactuca were the most studied. However, the highest antiparasitic activity was presented by the extract from macroalgae Stypopodium zonale, based on the extract concentration that can inhibit the parasites by 50% (IC50), while the species Tetraselmis suecica and Nostoc commune exhibited the best IC50 values among microalgae and cyanobacteria, respectively. Among all studies, only four active principles were identified, being elatol compound from Laurencia dendroidea the most promising based on its SI values for trypomastigotes (SI = 19.56) and amastigotes (SI = 26.73). The only in vivo study showed that microalgae Arthrospira maxima can be effective in T. cruzi-infected mice as treatment or prophylaxis. Although anti-T. cruzi activity of algal and cyanobacterial biocompounds is promising, further studies should exploit the mechanisms of action of the compounds, as well as new in vivo studies are required to make feasible future applications of these compounds for clinical trials in the treatment of CD.