Microstructured Polymer System Containing Proanthocyanidin-Enriched Extract from Limonium brasiliense as a Prophylaxis Strategy to Prevent Recurrence of Porphyromonas gingivalis.

Periodontal diseases are a global oral health problem affecting almost 10% of the global population. Porphyromonas gingivalis is one of the main bacteria involved in the initiation and progression of inflammatory processes as a result of the action of the cysteine proteases lysin- and arginine-gingipain. Surelease/polycarbophil microparticles containing a lyophilized proanthocyanidin-enriched fraction from the rhizomes of Limonium brasiliense, traditionally named "baicuru" (ethyl acetate fraction), were manufactured. The ethyl acetate fraction was characterized by UHPLC by the presence of samarangenins A and B (12.10 ± 0.07 and 21.05 ± 0.44%, respectively) and epigallocatechin-3-O-gallate (13.44 ± 0.27%). Physiochemical aspects of Surelease/polycarbophil microparticles were characterized concerning particle size, zeta potential, entrapment efficiency, ethyl acetate fraction release, and mucoadhesion. Additionally, the presence of the ethyl acetate fraction-loaded microparticles was performed concerning potential influence on viability of human buccal KB cells, P. gingivalis adhesion to KB cells, gingipain activity, and P. gingivalis biofilm formation. In general, all Surelease/polycarbophil microparticles tested showed strong adhesion to porcine cheek mucosa (93.1 ± 4.2% in a 30-min test), associated with a prolonged release of the ethyl acetate fraction (up to 16.5 ± 0.8% in 24 h). Preincubation of KB cells with Surelease/polycarbophil microparticles (25 µg/mL) resulted in an up to 93 ± 2% reduced infection rate by P. gingivalis. Decreased activity of the P. gingivalis-specific virulence factors lysin- and arginine-gingipain proteases by Surelease/polycarbophil microparticles was confirmed. Surelease/polycarbophil microparticles decreased biofilm formation of P. gingivalis (97 ± 2% at 60 µg/mL). Results from this study prove the promising activity of Surelease/polycarbophil microparticles containing ethyl acetate fraction microparticles as a prophylaxis strategy to prevent the recurrence of P. gingivalis.

Trypanocidal activity of 1,3,7-trihydroxy-2-(3-methylbut-2-enyl)-xanthone isolated from Kielmeyera coriacea.

This work evaluated the activity and ultrastructural and morphological alterations induced by the xanthone 1,3,7-trihydroxy-2-(3-methylbut-2-enyl)-xanthone (C23) isolated from Kielmeyera coriacea against Trypanosoma cruzi. This xanthone had inhibitory activity against the three forms of this protozoan and did not induce toxicity in mammalian cells. The best activity of this xanthone was against the intracellular amastigote form. Additionally, the mitochondrion was the main target of this compound, reflected by electronic microscopy and rhodamine 123 assays. Our MitoSOX assay results also indicated that C23 increased O2(-) production in mitochondrion. C23 might be a promising chemotherapeutic agent against T. cruzi because its trypanocidal action involves the disruption of mitochondrion, a specific target of Trypanosomatides.

Trypanocidal activity of guaianolide obtained from Tanacetum parthenium (L.) Schultz-Bip. and its combinational effect with benznidazole.

In the present study, we evaluated the in vitro antiprotozoal activity of a guaianolide (11,13-dehydrocompressanolide) isolated from Tanacetum parthenium against Trypanosoma cruzi and investigated the possible combinational effect of guaianolide and benznidazole. The isolated compound was shown to be effective against T. cruzi, with IC50 values of 18.1±0.8 and 66.6±1.3 µM against the multiplicative epimastigote and amastigote forms, respectively. The best results were obtained against trypomastigotes, with an EC50 of 5.7±0.7 µM. The guaianolide presented no toxicity in LLCMK2 cells (CC50 of 93.5 µM) and was 16.4-fold more selective for trypomastigotes. The study of the combinational effect of benznidazole and guaianolide revealed the presence of a synergistic effect against the epimastigote form and marginal additive effect against the trypomastigote form. Striking morphological changes were observed in epimastigotes treated with guaianolide, such as thinning and stretching of the cell body and flagellum and changes in the format of the cell body with apparent leakage of the cytoplasmic content in trypomastigote forms. The ultrastructural analysis of epimastigotes revealed the presence of membranes that involved organelles and formation of myelin-like figures. Flow cytometry revealed a cell volume reduction and decrease in mitochondrial membrane potential. However, no major changes in cell membrane integrity were found in the epimastigote form treated with guaianolide.

Mitochondria Superoxide Anion Production Contributes to Geranylgeraniol-Induced Death in Leishmania amazonensis.

Here we demonstrate the activity of geranylgeraniol, the major bioactive constituent from seeds of Bixa orellana, against Leishmania amazonensis. Geranylgeraniol was identified through (1)H and (13)C nuclear magnetic resonance imaging and DEPT. The compound inhibited the promastigote and intracellular amastigote forms, with IC(50) of 11 ± 1.0 and 17.5 ± 0.7 µg/mL, respectively. This compound was also more toxic to parasites than to macrophages and did not cause lysis in human blood cells. Morphological and ultrastructural changes induced by geranylgeraniol were observed in the protozoan by electronic microscopy and included mainly mitochondria alterations and an abnormal chromatin condensation in the nucleus. These alterations were confirmed by Rh 123 and TUNEL assays. Additionally, geranylgeraniol induces an increase in superoxide anion production. Collectively, our in vitro studies indicate geranylgeraniol as a selective antileishmanial that appears to be mediated by apoptosis-like cell death.