Browsing by Author "Cruz, Maria Teresa"
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- Antioxidant and dual dose-dependent antigenotoxic and genotoxic properties of an ethanol extract of propolisPublication . Cruz, Maria Teresa; Antunes, Paulo; Paulo, Luísa; Ferreira, A.M.; Cunha, A.; Aguiar, C. Almeida; Oliveira, RuiPropolis is a resinous product made by honeybees from plant-derived materials, with high content ofpolyphenols associated to several beneficial bioactivities with potential use as a natural food additive forpreservation and as a functional food ingredient. A Portuguese propolis ethanol extract (C.EE) protectedSaccharomyces cerevisiaecells from loss of viability upon exposure to H2O2, both in co- and in pre-incubation experiments. Results obtained with the comet assay suggest that lower concentrations areantigenotoxic while at higher concentrations a genotoxic effect prevails, which correlates with thecytotoxicity of high concentrations of C.EE. Flow cytometry analysis with dichlorofluorescein indicatesthat C.EE induced intracellular antioxidant activityin vivo. Overall the results suggest that C.EE isantigenotoxic but is also toxic at higher concentrations. This dual effect could be explained by thepresence of compounds known to interfere with DNA synthesis and/or cell proliferation, such as caffeicacid phenethyl ester (CAPE) and chrysin, together with antioxidants, like kaempferol, pinobanksin andpinocembrin.
- Antioxidant, anti-inflammatory, and analgesic activities of agrimonia eupatoria L. InfusionPublication . Santos, Telmo N.; Costa, Gustavo; Ferreira, J. Pinto; Liberal, Joana; Francisco, Vera; Paranhos, António; Cruz, Maria Teresa; Castel-Branco, Margarida; Figueiredo, I. Vitória; Batista, Maria TeresaAgrimony (Agrimonia eupatoria L.) (Ae) is used in traditional medicine to treat inflammatory and oxidative related diseases. Therefore, this study focuses on the anti-inflammatory and analgesic potential of Ae infusion (AeI). Phenolic compounds characterization was achieved by HPLC-PDA-ESI/MS (n) . To evaluate antioxidant potential, 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion, hydroxyl radical, and SNAP assays were used. In vitro anti-inflammatory activity of AeI was investigated in LPS-stimulated macrophages by measuring the NO production. In vivo anti-inflammatory activity was validated using the mouse carrageenan-induced paw edema model. Peripheral and central analgesic potential was evaluated using the acetic acid-induced writhing and hot-plate tests, respectively, as well as the formalin assay to assess both activities. The safety profile was disclosed in vitro and in vivo, using MTT and hematoxylin assays, respectively. Vitexin, quercetin O-galloyl-hexoside, and kaempferol O-acetyl-hexosyl-rhamnoside were referred to in this species for the first time. AeI and mainly AePF (Ae polyphenolic fraction) showed a significant antiradical activity against all tested radicals. Both AeI and AePF decreased NO levels in vitro, AePF being more active than AeI. In vivo anti-inflammatory and analgesic activities were verified for both samples at concentrations devoid of toxicity. Agrimony infusion and, mainly, AePF are potential sources of antiradical and anti-inflammatory polyphenols.
- Chemical composition of Laurencia obtusa extract and isolation of a new C15-acetogeninPublication . Esselin, Hélène; Sutour, Sylvain; Liberal, Joana; Cruz, Maria Teresa; Salgueiro, Lígia; Siegler, Benjamin; Freuze, Ingrid; Castola, Vincent; Paoli, Mathieu; Bighelli, Ange; Tomi, FélixA new C15-acetogenin, sagonenyne (20), exhibiting an unusual single tetrahydropyran ring was isolated from an ethyl acetate extract of Laurencia obtusa collected on the Corsican coastline. Its structure was established by detailed NMR spectroscopic analysis, mass spectrometry, and comparison with literature data. Twenty-three known compounds were identified in the same extract by means of column chromatography steps, using a (13)C-NMR computer aided method developed in our laboratory. In addition to sesquiterpenes, which represent the main chemical class of this extract, diterpenes, sterols, and C15-acetogenins were identified. The crude extract was submitted to a cytotoxicity assay and was particularly active against THP-1 cells, a human leukemia monocytic cell line.
- Lavandula viridis L´Hér. Essential oil inhibits the inflammatory response in macrophages through blockade of NF-KB signaling cascadePublication . Zuzarte, Mónica; Francisco, Vera; Neves, Bruno; Liberal, Joana; Cavaleiro, Carlos; Canhoto, Jorge; Salgueiro, Lígia; Cruz, Maria Teresa
- Urolithins impair cell proliferation, arrest the cell cycle and induce apoptosis in UMUC3 bladder cancer cellsPublication . Liberal, Joana; Carmo, Anália; Gomes, Célia; Cruz, Maria Teresa; Batista, Maria TeresaEllagitannins have been gaining attention as potential anticancer molecules. However, the low bioavailability of ellagitannins and their extensive metabolization in the gastrointestinal tract into ellagic acid and urolithins suggest that the health benefits of consuming ellagitannins rely on the direct effects of their metabolites. Recently, chemopreventive and chemotherapeutic activities were ascribed to urolithins. Nonetheless, there is still a need to screen and evaluate the selectivity of these molecules and to elucidate their cellular mechanisms of action. Therefore, this work focused on the antiproliferative effects of urolithins A, B and C and ellagic acid on different human tumor cell lines. The evaluation of cell viability and the determination of the half-maximal inhibitory concentrations indicated that the sensitivity to the studied urolithins varied markedly between the different cell lines, with the bladder cancer cells (UMUC3) being the most susceptible. In UMUC3 cells, urolithin A was the most active molecule, promoting cell cycle arrest at the G2/M checkpoint, increasing apoptotic cell death and inhibiting PI3K/Akt and MAPK signaling. Overall, the present study emphasizes the chemopreventive/chemotherapeutic potential of urolithins, highlighting the stronger effects of urolithin A and its potential to target transitional bladder cancer cells.