Mechanism of action and synergistic effect of Eugenia uniflora extract in Candida spp.

The limited arsenal of antifungal drugs have prompted the search for novel molecules with biological activity. This study aimed to characterize the antifungal mechanism of action of Eugenia uniflora extract and its synergistic activity with commercially available antifungal drugs on the following Candida species: C. albicans, C. tropicalis, C. glabrata, C. parapsilosis and C. dubliniensis. In silico analysis was performed to predict antifungal activity of the major compounds present in the extract. Minimal inhibitory concentrations (MICs) were determined in the presence of exogenous ergosterol and sorbitol. Yeast cells were grown in the presence of stressors. The loss of membrane integrity was assessed using propidium iodide staining (fluorescence emission). Synergism between the extract and antifungal compounds (in addition to time kill-curves) was determined. Molecular docking revealed possible interactions between myricitrin and acid gallic and enzymes involved in ergosterol and cell wall biosynthesis. Candida cells grown in the presence of the extract with addition of exogenous ergosterol and sorbitol showed 2 to 8-fold increased MICs. Strains treated with the extract revealed greater loss of membrane integrity when compared to their Fluconazole counterparts, but this effect was less pronounced than the membrane damage caused by Amphotericin B. The extract also made the strains more susceptible to Congo red and Calcofluor white. A synergistic action of the extract with Fluconazole and Micafungin was observed. The E. uniflora extract may be a viable option for the treatment of Candida infections.

Copaiba Oil-Loaded Polymeric Nanocapsules: Production and In Vitro Biosafety Evaluation on Lung Cells as a Pre-Formulation Step to Produce Phytotherapeutic Medicine.

Copaiba oil has been largely used due to its therapeutic properties. Nanocapsules were revealed to be a great nanosystem to carry natural oils due to their ability to improve the bioaccessibility and the bioavailability of lipophilic compounds. The aim of this study was to produce and characterize copaiba oil nanocapsules (CopNc) and to evaluate their hemocompatibility, cytotoxicity, and genotoxicity. Copaiba oil was chemically characterized by GC-MS and FTIR. CopNc was produced using the nanoprecipitation method. The physicochemical stability, toxicity, and biocompatibility of the systems, in vitro, were then evaluated. Β-bisabolene, cis-α-bergamotene, caryophyllene, and caryophyllene oxide were identified as the major copaiba oil components. CopNc showed a particle size of 215 ± 10 nm, a polydispersity index of 0.15 ± 0.01, and a zeta potential of -18 ± 1. These parameters remained unchanged over 30 days at 25 ± 2 °C. The encapsulation efficiency of CopNc was 54 ± 2%. CopNc neither induced hemolysis in erythrocytes, nor cytotoxic and genotoxic in lung cells at the range of concentrations from 50 to 200 µg·mL-1. In conclusion, CopNc showed suitable stability and physicochemical properties. Moreover, this formulation presented a remarkable safety profile on lung cells. These results may pave the way to further use CopNc for the development of phytotherapeutic medicine intended for pulmonary delivery of copaiba oil.

Determination of phenolic compounds and antioxidant potential of aqueous extracts of Curcuma longa L., Piper nigrum L. and Cuminum cyminum: an experimental and a quantum-mechanical study / Determinação de compostos fenólicos e potencial antioxidante dos extratos aquosos de Curcuma longa L., Piper nigrum L. e Cuminum cyminum: um estudo experimental e quanto-mecânico

Objectives: Evaluation of phenolic compounds and antioxidant activities of aqueous extracts of C. longa, P. nigrum and C. cyminum. In addition to proposing a quantum-mechanical model to evaluate the antioxidant activity. Methods: The aqueous extracts were prepared using roots of the Curcuma longa L., seeds of the Piper nigrum L. and seeds of Cuminum cyminum. The extracts were subjected to tests to detect and quantify phenolic compounds and to assess their antioxidant capacity by different methods. Furthermore, to investigate the electronic nature of the antioxidant activity of the main compounds present in these extracts, frontier molecular orbitals (FMOs) were obtained by the DFT/B3LYP/6-31G(d,p) level of theory. Results: After statistical analysis of the results, a greater number of phenolic compounds and better antioxidant activity was identified in the aqueous extracts of cumin (C. cyminum) in all three assays performed, when compared to the other extracts tested. The theoretical model based on the Pietro method is in agreement with the experimental results. Conclusion: This study has an innovative proposal with the trivial antioxidant activity combined with theoretical quantum-mechanical calculations that can serve to reduce costs and time and to predict the antioxidant activity of subsequent studies.

Objetivos: avaliar os compostos fenólicos e atividades antioxidantes dos extratos aquosos de C. longa, P. nigrum e C. cyminum bem como propor um modelo quanto-mecânico para avaliar a atividade antioxidante. Métodos: os extratos aquosos foram preparados por meio da utilização de raízes de Curcuma longa L., sementes de Piper nigrum L. e sementes de Cuminum cyminum. Os extratos foram submetidos a ensaios para detectar e quantificar compostos fenólicos e atividade antioxidante por diferentes métodos. Além disso, com objetivo de investigar a natureza eletrônica da atividade antioxidante dos principais compostos presentes nesses extratos, orbitais moleculares de fronteira (OMFs) foram obtidos pelo nível de teoria DFT/B3LYP/6-31G(d,p). Resultados: após as análises estatísticas dos resultados, a maior quantidade de compostos fenólicos com maior atividade antioxidante foi identificada no extrato aquoso do cominho (C. cyminum) em todos os ensaios realizados, quando comparados com os outros extratos testados. O modelo teórico baseado no método de Pietro está concordante com os resultados experimentais. Conclusão: este estudo possui uma proposta inovadora com a atividade antioxidante trivial combinada com cálculos quanto-mecânicos que podem servir para reduzir custos e tempo para predizer a atividade antioxidante de estudos futuros.

Anti-Inflammatory Activity of Bullfrog Oil Polymeric Nanocapsules: From the Design to Preclinical Trials.

BACKGROUND: Although bullfrog oil (BFO) exerts anti-inflammatory effects, it has undesirable properties limiting its use. METHODOLOGY: BFO nanocapsules (BFONc) were produced through nanoprecipitation, and their physicochemical and morphological properties were characterized. To evaluate the biocompatibility of the formulation, a mitochondrial activity evaluation assay was conducted, and cell uptake was assessed. The in vitro anti-inflammatory activity was evaluated by measuring reactive oxygen species (ROS), nitric oxide (NO), type-6 interleukin (IL-6), and tumor necrosis factor (TNF) levels. The in vivo anti-inflammatory effect was assessed by quantifying myeloperoxidase (MPO) levels using the carrageenan-induced paw edema model. RESULTS: BFONc showed a particle size of 233 ± 22 nm, a polydispersity index of 0.17 ± 0.03, and a zeta potential of -34 ± 2.6mV. BFONc revealed remarkable biocompatibility and did not induce changes in cell morphology. Furthermore, BFONc decreased ROS levels by 81 ± 4%; however, NO level increased by 72 ± 18%. TNF and IL-6 levels were reduced by approximately 10% and 90%, respectively. Significant in vivo anti-inflammatory activity was observed compared to dexamethasone. MPO levels were reduced up to 2 MPOs/mg. CONCLUSION: Taken together, the results pointed out the remarkable biocompatibility and anti-inflammatory effects of BFONc.

Live endothelial cells on plasma-nitrided and oxidized titanium: An approach for evaluating biocompatibility.

We evaluated the effects of titanium plasma nitriding and oxidation on live endothelial cell viscoelasticity. For this, mechanically polished titanium surfaces and two surfaces treated by planar cathode discharge in nitriding (36N2 and 24H2) and oxidant (36O2 and 24H2). Surfaces were characterized regarding wettability, roughness and chemical composition. Rabbit aortic endothelial cells (RAECs) were cultured on the titanium surfaces. Cell morphology, viability and viscoelasticity were evaluated by scanning electron microscopy (SEM), methyl thiazolyl tetrazolium (MTT) assay and atomic force microscopy (AFM), respectively. Grazing Incidence X-ray Diffraction confirmed the presence of TiN0,26 on the surface (grazing angle theta 1°) of the nitrided samples, decreasing with depth. On the oxidized surface had the formation of TiO3 on the material surface (Theta 1°) and in the deeper layers was noted, with a marked presence of Ti (Theta 3°). Both plasma treatments increased surface roughness and they are hydrophilic (angle <90°). However, oxidation led to a more hydrophilic titanium surface (66.59° ± 3.65 vs. 76.88° ± 2.68; p = 0.001) due to titanium oxide films in their stoichiometric varieties (Ti3O, TiO2, Ti6O), especially Ti3O. Despite focal adhesion on the surfaces, viability was different after 24 h, as cell viability on the oxidized surface was higher than on the nitrided surface (9.1 × 103 vs. 4.5 × 103cells; p < 0.05). This can be explained by analyzing the viscoelastic property of the cellular cytoskeleton (nuclear and peripheral) by AFM. Surface oxidation significantly increased RAECs viscoelasticity at cell periphery, in comparison to the nucleus (2.36 ± 0.3 vs. 1.5 ± 0.4; p < 0.05), and to the RAECs periphery in contact with nitrided surfaces (1.36 ± 0.7; p < 0.05) and polished surfaces (1.55 ± 0.6; p < 0.05). Taken together, our results have shown that titanium plasma treatment directly increased cell viscoelasticity via surface oxidation, and this mechanobiological property subsequently increased biocompatibility.

In vitro antitumor and anti-angiogenic activities of a shrimp chondroitin sulfate.

Thrombin triggers cellular responses that are crucial for development and progression of cancer, such as proliferation, migration, oncogene expression and angiogenesis. Thus, biomolecules capable of inhibiting this protease have become targets in cancer research. The present work describes the in vitro antitumor properties of a chondroitin sulfate with anti-thrombin activity, isolated from the Litopenaeus vannamei shrimp (sCS). Although the compound was unable to induce cytotoxicity or cell death and/or cell cycle changes after 24 h incubation, it showed a long-term antiproliferative effect, reducing the tumor colony formation of melanoma cells by 75% at 100 µg/mL concentration and inhibiting the anchorage-independent colony formation. sCS reduced 66% of melanoma cell migration in the wound healing assay and 70% in the transwell assay. The compound also decreased melanin and TNF-α content of melanoma cells by 52% and 75% respectively. Anti-angiogenic experiments showed that sCS promoted 100% reduction of tubular structure formation at 100 µg/mL. These results are in accordance with the sCS-mediated in vitro expression of genes related to melanoma development (Cx-43, MAPK, RhoA, PAFR, NFKB1 and VEGFA). These findings bring a new insight to CS molecules in cancer biology that can contribute to ongoing studies for new approaches in designing anti-tumor therapy.

Prosopis juliflora as a new cosmetic ingredient: Development and clinical evaluation of a bioactive moisturizing and anti-aging innovative solid core.

Prosopis juliflora is an invasive plant distributed throughout the world and presents metabolites of interest for cosmetology. The aim of this work was to develop a new polysaccharide-based ingredient from P. juliflora and analyze its application in a solid core formulation that upon contact with water instantly forms a gel to improve moisturizing and anti-aging skin properties. Purified extracts by gel chromatography were characterized by NMR and LC-DAD-MS-MS. The in vitro and in vivo safety, antioxidant activity, formulation development and clinical evaluation were performed. The extract was characterized as containing an α-glucan and phenolics. It was non-cytotoxic, non-phototoxic and no skin reactions were observed in vivo. Antioxidant activity were present through different mechanisms. Clinical evaluation reinforced the potential of P. juliflora in skin hydration and microrelief improvement. This innovative form proved to be a prototype of a new product and the first study of an α-glucan as a cosmetic ingredient.

Bullfrog Oil Reduces the Carrageenan-induced Edema in Wistar Rats by in vitro Reduction of Inflammatory Mediators.

Bullfrog oil (BFO) is a natural product from the adipose tissue of the amphibian Rana catesbeiana Shaw, a bio-product rich in polyunsaturated fatty acids, which claims anti-inflammatory activity. The objective of this work was to evaluate the cytotoxicity and the anti-inflammatory activity of BFO using in vivo and in vitro assays. Thus, the in vitro cytotoxicity was assessed by the MTT assay. Additionally, the in vivo anti-inflammatory activity was performed by the carrageenan-induced paw edema model in Wistar rats, followed by histological analysis. Moreover, the BFO effect on inflammatory pathways was investigated by in vitro evaluation of the nitric oxide (NO) synthesis, and type-6 interleukin (IL-6) and tumor-necrosis-factor (TNF) levels. In vivo experiments showed that BFO administered by intragastric route produced a significant anti-inflammatory effect, which was as substantial as indomethacin, the positive control. Histopathological analysis confirmed these results, showing the absence of the edema and minimal signs of inflammation in the paws of rats treated with BFO. The MTT results showed that BFO at all tested concentrations had no toxic effect against a macrophage cell line, not affecting the cell viability. In addition, after 48 hours of treatment, the BFO itself and its blend with Cetiol®-V (1:1v/v) at 200 µg.mL-1 were able to reduce the NO synthesis, and the IL-6 and TNF levels up to 35 ± 2%, 40 ± 6%, and 12 ± 3%, respectively. Therefore, these results provide unprecedented scientific evidence of the anti-inflammatory effect of BFO, suggesting its potential as a new candidate for the development of pharmaceutical products with anti-inflammatory activity.

Plasma nitriding under low temperature improves the endothelial cell biocompatibility of 316L stainless steel.

OBJECTIVES: To evaluate the effects of the surface modification of 316L stainless steel (SS) by low-temperature plasma nitriding on endothelial cells for stent applications. RESULTS: X-ray diffraction (XRD) confirmed the incorporation of nitrogen into the treated steel. The surface treatment significantly increased SS roughness and hydrophilic characteristics. After 4 h the cells adhered to the nitride surfaces and formed clusters. During the 24 h incubation period, cell viability on the nitrided surface was higher compared to the polished surface. Nitriding reduced late apoptosis of rabbit aorta endothelial cell (RAEC) on the SS surface. CONCLUSION: Low temperature plasma nitriding improved the biocompatible of stainless steel for use in stents.

Analogs of the Scorpion Venom Peptide Stigmurin: Structural Assessment, Toxicity, and Increased Antimicrobial Activity.

Scorpion venom is a rich source of biologically active components and various peptides with high-potential therapeutic use that have been characterized for their antimicrobial and antiproliferative activities. Stigmurin is a peptide identified from the Tityus stigmurus venom gland with high antibacterial and antiproliferative activities and low toxicity. Amino acid substitutions in peptides without a disulfide bridge sequence have been made with the aim of reducing their toxicity and increasing their biological activities. The purpose of this study was to evaluate the structural conformation and structural stability, as well as antimicrobial, antiproliferative, and hemolytic activities of two peptide analogs to Stigmurin, denominated StigA6 and StigA16. In silico analysis revealed the α-helix structure for both analog peptides, which was confirmed by circular dichroism. Data showed that the net charge and hydrophobic moment of the analog peptides were higher than those for Stigmurin, which can explain the increase in antimicrobial activity presented by them. Both analog peptides exhibited activity on cancerous cells similar to the native peptide; however, they were less toxic when tested on the normal cell line. These results reveal a potential biotechnological application of the analog peptides StigA6 and StigA16 as prototypes to new therapeutic agents.