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- Antileishmanial activity of meroditerpenoids from the macroalgae Cystoseira baccataPublication . Sousa, Carolina Bruno de; Gangadhar, Katkam N.; Morais, Thiago R.; Conserva, Geanne A. A.; Vizetto-Duarte, C; Pereira, H.; Laurenti, Marcia D.; Campino, Lenea; Levy, Debora; Uemi, Miriam; Barreira, Luísa; Custódio, L.; Passero, Luiz Felipe D.; Lago, Joao Henrique G.; Varela, JoãoThe development of novel drugs for the treatment of leishmaniases continues to be crucial to overcome the severe impacts of these diseases on human and animal health. Several bioactivities have been described in extracts from macroalgae belonging to the Cystoseira genus. However, none of the studies has reported the chemical compounds responsible for the antileishmanial activity observed upon incubation of the parasite with the aforementioned extracts. Thus, this work aimed to isolate and characterize the molecules present in a hexane extract of Cystoseira baccata that was found to be bioactive against Leishmania infantum in a previous screening effort. A bioactivity-guided fractionation of the C. baccata extract was carried out and the inhibitory potential of the isolated compounds was evaluated via the MIT assay against promastigotes and murine macrophages as well as direct counting against intracellular amastigotes. Moreover, the promastigote ultrastructure, DNA fragmentation and changes in the mitochondrial potential were assessed to unravel their mechanism of action. In this process, two antileishmanial meroditerpenoids, (3R)- and (3S)-tetraprenyltoluquinol (1a/1b) and (3R)- and (3S)-tetraprenyltoluquinone (2a/2b), were isolated. Compounds 1 and 2 inhibited the growth of the L. infantum promastigotes (IC50 = 44.9 +/- 4.3 and 94.4 +/- 10.1 mu M, respectively), inducing cytoplasmic vacuolization and the presence of coiled multilamellar structures in mitochondria as well as an intense disruption of the mitochondrial membrane potential. Compound 1 decreased the intracellular infection index (IC50 = 25.0 +/- 4.1 mu M), while compound 2 eliminated 50% of the intracellular amastigotes at a concentration > 88.0 mu M. This work identified compound 2 as a novel metabolite and compound 1 as a biochemical isolated from Cystoseira algae displaying antileishmanial activity. Compound 1 can thus be an interesting scaffold for the development of novel chemotherapeutic molecules for canine and human visceral leishmaniases studies. This work reinforces the evidence of the marine environment as source of novel molecules. (C) 2017 Elsevier Inc. All rights reserved.
- Cystoseira algae (Fucaceae): update on their chemical entities and biological activitiesPublication . Bruno De Sousa, Carolina; Gangadhar N. Katkam, Dr.; Macridachis, Jorge; Pavao, Madalena; Morais, Thiago R.; Campino, Lenea; J. C. or Varela J. or Varela J.C.S., Varela; Lago, Joao Henrique G.Cystoseira (Sargassaceae) is a genus of marine brown algae composed of about 40 species, which is distributed along the Eastern Atlantic and Mediterranean coasts. The biological potential of the Cystoseira genus has been investigated and several activities have been reported. Chemically, this genus contains a wide variety of secondary metabolites, such as terpenoids, steroids, phlorotannins and phenolic compounds. Additionally, other chemical components as, for instance, carbohydrates, triacylglycerolsgatty acids, pigments as well as vitamins have been identified in the studied species. Some of the isolated compounds were associated with the reported pharmacological properties, as for example antioxidant, anti-inflammatory, cytotoxicity, anticancer, cholinesterase inhibition, anti-diabetic, activities but also antibacterial, antifungal and anti-parasitic activities. In this review, we provide a comprehensive overview of the compounds isolated and identified after 1995 from the different species of Cystoseira, compiling more than 200 compounds isolated, together with their therapeutic potential. (C) 2017 Elsevier Ltd. All rights reserved.
- Report of in vitro antileishmanial properties of Iberian macroalgaePublication . Bruno De Sousa, Carolina; Lago, Joao Henrique G.; Macridachis, Jorge; Oliveira, Marta; Fonseca Brito, Luis; Vizetto-Duarte, Catarina; Florindo, Claudia; Hendrickx, Sarah; Maes, Louis; Morais, Thiago; Uemi, Miriam; Neto, Luis; Dionísio, Lídia; Cortes, Sofia; Barreira, Luísa; Custódio, Luísa; Albericio, Fernando; Campino, Lenea; Varela, J.Here is reported the anti Leishmania infantum activity of 48 hexane, CH2Cl2 and MeOH extracts from 16 macroalgae collected on the Iberian Coast. Seven hexane and CH2Cl2 Cystoseira baccata, Cystoseira barbata, Cystoseira tamariscifolia, Cystoseira usneoides, Dictyota spiralis and Plocamium cartilagineum extracts were active towards promastigotes (IC50 29.8-101.8 mu g/mL) inducing strong morphological alterations in the parasites. Hexane extracts of C. baccata and C. barbata were also active against intracellular amastigotes (IC50 5.1 and 6.8 mu g/mL, respectively). Fatty acids, triacylglycerols, carotenoids, steroids and meroterpenoids were detected by nuclear magnetic resonance (NMR), and gas chromatography in the Cystoseira extracts. These results suggest that Cystoseira macroalgae contain compounds with antileishmanial activity, which could be explored as scaffolds to the development of novel sources of antiparasitic derivatives. [GRAPHICS] .