Examinando por Autor "Villena, Joan"

Mostrando 1 - 6 de 6
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    Antioxidant and Anti-Proliferative Activity of Essential Oil and Main Components from Leaves of Aloysia polystachya Harvested in Central Chile
    (MDPI, 2021) Catalina Moller, Alejandra; Parra, Carol; Said, Bastian; Werner, Enrique; Flores, Susana; Villena, Joan; Russo, Alessandra; Caro, Nelson; Montenegro, Iván; Madrid, Alejandro
    The aim of this study was to determine, first, the chemical composition of Aloysia polystachya (Griseb) Moldenke essential oil, from leaves harvested in central Chile; and second, its antioxidant and cytotoxic activity. Eight compounds were identified via gas chromatography–mass spectrometry (GC–MS) analyses, with the most representative being R-carvone (91.03%), R-limonene (4.10%), and dihydrocarvone (1.07%). For Aloysia polystachya essential oil, antioxidant assays (2,2-diphenyl1-picrylhydrazyl (DPPH), H2O2, ferric reducing antioxidant power (FRAP), and total reactive antioxidant potential (TRAP)) showed good antioxidant activity compared to commercial antioxidant controls; and anti-proliferative assays against three human cancer cell lines (colon, HT-29; prostate, PC-3; and breast, MCF-7) determined an IC50 of 5.85, 6.74, and 9.53 μg/mL, and selectivity indices of 4.75, 4.12, and 2.92 for HT-29, PC-3, and MCF-7, respectively. We also report on assays with CCD 841 CoN (colon epithelial). Overall, results from this study may represent, in the near future, developments for natural-based cancer treatments.
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    Caracterización poblacional del antígeno CD271 en células de pulpa y papila dental humana con inmunofenotipo de célula madre mesenquimática
    (Universidad de Valparaíso, 2015) Moreno Silva, Ricardo; San Martin, Sebastián; Villena, Joan
    En los últimos años, el aislamiento y la utilización de células madre mesenquimáticas (MSCs) multipotenciales han sido ampliamente reportados, tanto en el área de la investigación biomédica así como en la de sus aplicaciones clínicas relacionadas con la Ingeniería de Tejidos y Medicina Regenerativa, con foco en la capacidad de clonogenicidad en el tiempo, de diferenciación a diversos linajes celulares, de migrar a tejidos que las necesitan y de tener propiedades inmunomodulatorias. Las MSCs fueron aisladas primero desde médula ósea y se ha reportado su obtención desde múltiples tejidos mesenquimáticos vascularizados, entre ellos la pulpa dental. Según la International Society for Cellular Therapy, la identificación de MSC incluye criterios inmunofenotípicos como el presentar marcación positiva para los antígenos CD73, CD90 y CD105 y negativa para los antígenos hemopoyéticos CD45, CD34, CD14 o CD11b, CD79α o CD19 y HLA-DR, así como los criterios de la adherencia al plástico en el cultivo y la capacidad de diferenciación a osteoblastos, condroblastos y adipocitos. Las células de la pulpa y papila dental provienen embriológicamente de las crestas neurales. El antígeno CD271 (p75 o LNGFR) surge como uno de los marcadores característicos de célula madre provenientes de ellas, además que se lo ha usado como marcador único para realizar el aislamiento de MSC en otros tejidos. Por ello, nos preguntamos si las células de pulpa y papila dental de dientes definitivos que presentan un inmunofenotipo característico de MSC poseen además el antígeno CD271. Diseñamos una investigación que utilizó citometría de flujo y microscopía de fluorescencia para determinarlo en células en cultivo primario de pulpa y papila dental de terceros molares humanos. Nuestros hallazgos concluyen que alrededor del 91% de las células de pulpa y papila dental en cultivo con inmunofenotipo de MSC, presentan además el antígeno CD271.
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    Chemical Composition, Antioxidant and Anticancer Activities of Leptocarpha rivularis DC Flower Extracts
    (MDPI, 2021) Montenegro, Jorge; Moreira, Jorge; Ramirez, Ingrid; Dorta, Fernando; Sánchez, Elizabeth; Alfaro, Juan Felipe; Valenzuela, Manuel; Jara-Gutiérrez, Carlos; Muñoz, Ociel; Alvear, Matías; Werner, Enrique; Madrid, Alejandro; Villena, Joan; Seeger, Michael
    An evaluation of antioxidant and anticancer activity was screened in Leptocarpha rivularis DC flower extracts using four solvents (n-hexane (Hex), dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol (EtOH)). Extracts were compared for total extract flavonoids and phenol contents, antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), ferric reducing antioxidant potential (FRAP), total reactive antioxidant properties (TRAP) and oxygen radical absorbance capacity (ORAC)) across a determined value of reduced/oxidized glutathione (GSH/GSSG), and cell viability (the sulforhodamine B (SRB) assay). The most active extracts were analyzed by chromatographic analysis (GC/MS) and tested for apoptotic pathways. Extracts from Hex, DCM and AcOEt reduced cell viability, caused changes in cell morphology, affected mitochondrial membrane permeability, and induced caspase activation in tumor cell lines HT-29, PC-3, and MCF-7. These effects were generally less pronounced in the HEK-293 cell line (nontumor cells), indicating clear selectivity towards tumor cell lines. We attribute likely extract activity to the presence of sesquiterpene lactones, in combination with other components like steroids and flavonoids.
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    Cytotoxic activity of crude extracts and fractions from Blepharocalyx cruckshanksii against selected human cancer cell lines
    (Ms Editions, 2020) Baez, Carolina; Villena, Joan; Montenegro, Iván; Russo, Alessandra; Said, Bastian; Madrid, Alejandro
    El presente estudio tiene como objetivo explorar las posibles aplicaciones de los extractos de corteza y hoja de Blepharocalyx cruckshanksii como agente citotóxico contra líneas celulares de cáncer in vitro ((MCF-7, PC-3 y HT-29) mediante el uso de ensayo de sulforhodamine B (SRB). El ensayo de citotoxicidad reveló que el extracto de acetato de etilo de la corteza exhibía una actividad anticancerígena marcada. El extracto activo se sometió a un reparto líquido-líquido usando hexano y acetato de etilo para obtener fracciones basadas en su polaridad. Sin embargo, la Fracción 4 (F4) fue identificado como el más efectivo de la serie al mostrar contra todas las líneas celulares de cáncer una citotoxicidad cercana a los agentes antineoplásicos ensayados. Luego, F4 se analizó por cromatografía de gases-espectrometría de masas (GC-MS) para identificar sus componentes principales y relacionar estos componentes con el efecto citotóxico. Los resultados obtenidos indicaron que la corteza de B. cruckshanksii tiene una excelente actividad citotóxica y amerita estudios adicionales para aislar nuevos compuestos para quimioterapia.
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    Inhibition of Caco-2 and MCF-7 cancer cells using chalcones: synthesis, biological evaluation and computational study
    (Taylor & Francis, 2021) Mellado, Marco; Reyna-Jeldes, Mauricio; Weinstein-Oppenheimer, Caroline; Coddou, Claudio; Jara-Gutierrez, Carlos; Villena, Joan; Aguilar, Luis F.
    Cancer is the second death cause worldwide, with breast and colon cancer among the most prevalent types. Traditional treatment strategies have several side effects that inspire the development of novel anticancer agents derived from natural sources, like chalcone derivatives. For this investigation, twenty-three chalcones (4a-w) were synthesized and evaluated as antiproliferative agents against MCF-7 and Caco-2 cells, finding three and two compounds with similar or higher antiproliferative activity than daunorubicin, while only two chalcones showed better selectivity indexes than daunorubicin on MCF-7. From these results, we developed good-performance QSAR models (r> 0.850, q2 >0.650), finding several structural features that could modify chalcone activity and selectivity. According to these models, chalcones 4w and 4t have high potency and selectivity against Caco-2 and MCF-7, respectively, which make them attractive candidates for hit-to-lead development of ROS-independent pro apoptotic agents.
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    Ultrasound assisted synthesis and cytotoxicity evaluation of known 2′ ,4′ -dihydroxychalcone derivatives against cancer cell lines
    (Elsevier, 2021) Villena, Joan; Montenegro, Ivan; Said, Bastian; Werner, Enrique; Flores, Susana; Madrid, Alejandro
    This work reports on the development of an efficient and ecofriendly ultrasound assisted method for the high yield synthesis (70.0–94.0%) of eighteen oxyalkylated derivatives of 2′ ,4′ -dihydroxychalcone. Synthesized compounds were subjected to in vitro biological assays against HT-29 (colorectal), MCF-7 (breast), and PC-3 (prostate) human tumor cell lines, these cell lines are among the ten most aggressive malignancies diagnosed in the world. Cytotoxicity evaluations showed that four of the synthesized compounds exhibited moderate to very high toxic activity against MCF-7 (IC50 = 8.4–34.3 μM) and PC-3 (IC50 = 9.3–29.4 μM) – comparable to 5-fluorouracil (IC50 16.4–22.3 μM). The same compounds only showed moderate activity against HT-29 (IC50 15.3–36.3 μM), closer to daunorubicin (IC50 15.1 μM). Next, although selectivity index (SI) of compounds was weak, compound 18 exhibited a remarkable and selective cytotoxic activity (5.8–10.57) against cancer cells. Outside of these, most compounds significantly reduced cell survival, increased reactive oxygen species (ROS) and caspase activity, and decreased mitochondrial membrane permeability. In this sense, a portion of antiproliferative activity is due to apoptosis. Notwithstanding, due to its remarkable response, chalcone 18 may be a potential alternative as a chemotherapeutic anti-carcinogen.